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Ann. Limnol. - Int. J. Lim.
Volume 56, 2020
|Article Number
|Number of page(s)
|Published online
|24 March 2020
Research Article
Plankton characterization of alpine ponds: a case of study for the assessment of water quality in Serra da Estrela (Portugal)
Departamento de Biologia da Faculdade de Ciências da Universidade do Porto (FCUP), Rua do Campo Alegre s/n, 4169-007 Porto, Portugal
2 Centro Interdisciplinar de Investigação Marinha e Ambiental (CIIMAR/CIMAR), Novo Edifício do Terminal de Cruzeiros do Porto de Leixões, Av. General Norton de Matos s/n, 4050-208 Matosinhos, Portugal Rua dos Bragas 289, 4050-123 Porto, Portugal
3 Departamento de Geociências, Ambiente e Ordenamento do Território da Faculdade de Ciências da Universidade do Porto (FCUP), Rua do Campo Alegre s/n, 4169-007 Porto, Portugal
4 Instituto de Ciências da Terra (ICT, Polo do Porto), Rua do Campo Alegre s/n, 4169-007 Porto, Portugal
* Corresponding author: email@example.com
Accepted: 14 January 2020
Serra da Estrela is Portugal's mainland highest mountain, with distinctive geological, climatic and geomorphological characteristics which play a key role on surface and groundwater resources. These mountains have the largest set of glacial ponds of Portugal and are scarcely studied. Besides, there are concerns of possible impacts of the use of salts in road de-icing on ponds' biotic communities. This research intends to characterize the hydrology of five Mediterranean alpine ponds and assess their planktonic communities. The biotic index proposed by the Water Framework Directive for lentic systems was used to check its applicability to these systems. Sampling was conducted monthly from June to November 2015 alongside with hydrological characterization. Water parameters and nutrients' content were quantified. Phytoplankton and macrozooplankton were identified. Ponds' water level is controlled by precipitation (input) and evaporation, infiltration and streamflow (output). Ponds were in good ecological quality. However, the current ecological assessment tools proposed by the WFD for lentic systems do not fit alpine ponds, showing a gap in the current methods. Salts used for road de-icing did not impact the communities and the ecological state of ponds. Phytoplankton was dominated by Cyanobacteria, Dinophyceae and Bacillariophyceae; Cyclopoida was the most abundant zooplanktonic group. For macrozooplankton, RDA shows association between cladocerans and phosphorus content. Phosphorus changes promoted shifts in zooplankton, what may be of major concern from a conservation point of view, once alpine ponds and its species are still mostly unknown. Efforts should be done to develop tools to classify aquatic ecosystems from harsh environments.
Key words: Phytoplankton / zooplankton / Water Framework Directive / hydrology / Mediterranean ponds
© EDP Sciences, 2020
1 Introduction
Lentic ecosystems are inland surface freshwater ecosystems (such as lakes, ponds, pools, puddles, swamps) which have a key role in providing resources and habitats to aquatic and terrestrial organisms. These ecosystems can be classified as permanent or temporary waterbodies, and the main abiotic factors that control their dynamics are bedrock type, morphology, basin soil type, vegetation, nutrients content, light availability, oxygen levels, temperature, and pH conditions (e.g. Kamenik et al., 2001; Brönmark and Hansson, 2002). However, biotic interactions are important processes affecting the species diversity and composition, and therefore the ecosystems' dynamic and functioning. These factors may operate at different spatial and temporal scales (Brönmark and Hansson, 2002; Hoverman and Johnson, 2012).
Alpine ponds are an example of this situation. These water bodies are often generated by glacial processes, as the movement of glaciers erodes the loose soil and/or the bedrock, creating depressions which are later filled with water from precipitation or melted ice (Bengtsson, 2012). These ponds are typically located at high altitudes, above the local treeline (Tolotti et al., 2006). The prevailing environmental conditions affecting high altitude ponds include low rock weathering, poor soil development, highly diluted waters, thinner atmosphere (leading to higher UV radiation during the ice-free period) and light limited conditions during the winter season due to snow and ice accumulation (Catalan et al., 2006). At higher altitudes, air temperature is lower, and precipitation is higher, resulting in short growth periods, high water renewal rates and poor buffering capacity. Therefore, mountain ecosystems are very sensitive to external changes, even to small ones. On the other hand, anthropogenic pressure such as inadequate forest management, uncontrolled tourism, and acidic deposition and road de-icing are another group of factors that promote significant alterations on the ecosystem functioning (Céréghino et al., 2008; Oertli et al., 2008; Espinha Marques et al., 2019).
Species that occur in this type of habitat have adaptations that allow them to survive to such conditions. For instance, plant species have a great colonization ability, phytoplankton can be mixotrophic (i.e. both autotrophic and heterotrophic types of nutrition), may encyst when there are adverse conditions and zooplankton can enter diapause or overwinter as resting eggs (Bell, 2012). These traits make these species apt to fit these specific climatic conditions but the high degree of adaptation to alpine ecosystems can also make them very vulnerable to environmental changes. The rising temperature may lead to habitat loss and severe species ranges contractions, enhancing also biotic pressures, such as competition for resources (Bell, 2012). Alpine ponds are characterized by simple food webs and low resilience, which means that they are more likely to be negatively affected by small disturbances. Thus, alpine ponds are considered highly sensitive to environmental changes (Watson and Haeberli, 2004; Tolotti et al., 2006; Toro et al., 2006), therefore, are considered prime areas of environmental concern (Bell, 2012). The highly specific conditions of this environments, variable hydroperiods, remoteness, and stochastic events allow similar ponds to have distinct biological communities contributing to a higher regional diversity, making ponds important biodiversity hotspots (Williams et al., 2004).
It is known that phytoplankton assemblages alter rapidly in response to changes in water quality. These communities initially show quantitative changes and, later, qualitative changes in the community structure (Bouchard, 2005; Brettum and Andersen, 2005). Thus, phytoplankton is the only biological quality element for pond or lake classification, according to the Water Framework Directive, WFD (Directive 2000/60/CE), namely concerning their quantification in terms of biomass, abundance, and composition. In addition to biological criteria, hydromorphological elements, morphological conditions, and chemical and physical parameters are used to evaluate water quality and the ecological state of lakes and ponds (Directive 2000/60/CE). Likewise, zooplankton can be used as an indicator of trophic conditions of freshwater ecosystems (Caroni and Irvine, 2010; Jeppesen et al., 2011; Jensen et al., 2013). Yet, in the WFD metrics, this plankton community is not contemplated. Zooplankton is in a central position in food webs (primary consumer) and establishes the energy flow connection between primary producers (phytoplankton) and predators (planktivorous fish) (Jeppesen et al., 2011; Du et al., 2015), and is also important in nutrient cycling for microalgae (Jensen et al., 2013; Li et al., 2014). The main goal of WFD is to protect all water bodies. However, small water bodies such as pools and ponds remain unmonitored and usually are not considered in protection measures. The protection and management of alpine ponds are relevant for improving the implementation of the WFD as well of other EU water legislation and policies.
Lakes and ponds with long turnover time and low flow are waterbodies more susceptible to road salt contamination. The accumulation of salt in waterbody and in the groundwater supplies leads to an increase of biochemical oxygen demand, accelerated eutrophication, alteration of pH level and stratification of the waterbody (D'Itri, 1992). In addition to chemical changes, biological communities are affected by the increase of salt concentration and will potentially lead to a decrease in growth and reproductive output (Van Meter et al., 2011). Furthermore, the use of de-icing agents may present new conditions that exceed the species capacity for adaptation, surpassing their tolerances and thresholds (Van Meter et al., 2011). Several studies show that either phytoplankton and zooplankton are potentially vulnerable to de-icing salts (Dixit et al., 1999; Van Meter et al., 2011). However, the primary producers are more affected by these road salts than more complex organisms, and the chemical de-icers contamination in aquatic ecosystems is usually too low to be considered toxic for zooplankton (Judd et al., 2005; Langen et al., 2006).
The study site is located in Serra da Estrela (Central Portugal), and its territory corresponds to a protected area, a National Park, with an area of around 88,850 ha, from the Castelo Branco and Guarda districts. The Torre summit (1993 m a.s.l.) is the highest point of inland Portugal and is an important touristic point. Since the local economy is greatly dependant on tourism, mountain roads must remain free of snow and ice, especially after winter storms. For that reason, the local authorities carry out frequent de-icing operations, particularly above 1500 m a.s.l., producing changes on water, soil and on mountains ecosystems (Carvalho et al., 2012). As a result, ecosystems associated to water bodies located downstream from roads, namely, streams, aquifers and alpine ponds may experience hydrochemical changes which will probably affect the respective biota. The road de-icing agent typically used in Serra da Estrela is NaCl from rock salt, but CaCl2 is also applied after particularly intense winter storms, which result in the formation of greater amounts of ice (Rodrigues et al., 2010; Carvalho et al., 2012; Espinha Marques et al., 2019). The salt may reach streams, lakes and ponds, and may even infiltrate into groundwater, leading to a higher salt concentration that will probably affect the biota and water chemistry (Rodrigues et al., 2010).
This study intends to use a multidisciplinary approach to characterize the hydrology of five natural alpine ponds of Serra da Estrela, the water physical and chemical status, and biotic communities (phytoplankton and macrozooplankton), in order to assess the ecological status of these aquatic natural and extreme ecosystems.
2 Methods
2.1 Site description
Serra da Estrela (40° 15'-38'N; 7° 18'-47'W) is part of the Cordilheira Central, an ENE-WSW mountain range that crosses the Iberian Peninsula (Fig. 1). The regional climate has Mediterranean and Atlantic influence. The mean annual precipitation is around 2500 mm in the most elevated areas, the wet season ranges from October to May and the mean annual air temperature is below 7 °C in the highest part of the mountain, but may reach 4 °C at the Torre summit (Daveau et al., 1977; Miranda et al., 2006). The Köppen-Geiger climatic classification is Csb (warm temperate, with dry and warm summers), similarly to Northwestern Iberia (Kottek et al., 2006; Peel et al., 2007).
The Serra da Estrela hydrogeological units encompass sedimentary cover (mainly glacial, fluvioglacial and alluvial deposits), metasedimentary rocks and granitic rocks (e.g. Marques et al., 2013). Yet, at the study site only granitic rocks occur. The Serra da Estrela alpine ponds occur on depressions originated by glacial erosion during the Last Glacial Maximum (Daveau et al., 1997; Vieira, 2008).
This study was conducted in five shallow natural alpine ponds (numbered from P1 to P5) located in Serra da Estrela, in granitic terrain, with area ranging from 718 m2 to 18,672 m2 (Fig. 2 and Tab. 1). All ponds are located above 1700 m a.s.l. and present alpine conditions, freezing completely at mid-autumn, and the thaw occurs at the beginning of the spring season. All the ponds are permanent, except for P2 that was dry in two of the sampled months (Aug–Sep). There is a possible connection to groundwater flow in P2 and P5. These two ponds also have connection to the drainage network and have significant sediment infilling. The rest of the ponds do not present connections and have insignificant sediment infilling.
Fig. 1
Serra da Estrela Natural Park geographical setting and location of the study area.
Fig. 2
Drainage network of the studied ponds.
Pond physical and morphometric features.
2.2 Sampling procedures
The study was conducted from June to November (2015) and water sampling was carried out monthly in all five ponds. In situ physical and chemical parameters (dissolved oxygen (mg/L and %), pH, conductivity (μS/cm), and temperature (°C)) were determined using a multiparametric probe. Zooplankton sampling was made by filtering 12 L of water collected sub-superficial through a 0.55 μm mesh in different habitats of each pond in order to make a compost sample that would represent all the pond's habitats, and then stored in ethanol at 96%. An additional water sample was collected on 1.5-L plastic bottles for later quantification of other physical, chemical and biological parameters (photosynthetic pigments and suspended solids), as well as for chemical analysis (nutrients and hardness). All bottles were immediately placed in the dark, at 4 °C and transported to the laboratory.
2.3 Laboratory procedures
2.3.1 Physical and chemical parameters
In the laboratory, water samples for chemical determinations were thawed and analyses were performed according to each parameter. Phosphorus (TP), nitrate (NO3–), nitrites (NO2–), ammonia (NH4+), turbidity (Turb), and water hardness quantifications followed the procedures described in APHA/AWWA/WEF (2012). Dissolved organic carbon in water samples was indirectly determined through the colour of water (CDOC) as described by Williamson et al. (1999). For the determination of suspended solids an aliquot of water from each pond was filtered through pre-weighed Whatman GF/C filters (1.2 µm porosity, 47 mm diameter). Total suspended solids were calculated after obtaining dry weights (dried at 60 °C for 24 h) and ash-free dry weights (ignited at 450 °C for 8 h) of the filtered residues (adapted from Lind, 1985; APHA et al., 1989).
For the determination of chlorophyll a concentration, an aliquot of water from each pond was filtered through a Whatman GF/C filter (1.2 µm porosity, 47 mm diameter). After this, filters were immersed in 90% acetone and stored in the dark at 4 °C for 24 h, to complete pigment extraction (Strickland and Parsons, 1972; Lind, 1985). After a short centrifugation, the absorbance of the extracts was read at 665 nm and 750 nm (in a Spectronic 20 Genesys spectrophotometer), before and after acidification with HCl. Chlorophyll a (Chl a) concentration was calculated according to Lorenzen's (1967) monochromatic equations. The Trophic State Index was obtained for each pond using the chlorophyll a content (Carlson, 1977).
2.4 Biological parameters
Phytoplankton quantification followed INAG's protocol (INAG, 2009a) and Lund et al. (1958) procedures. A sedimentation of 800 mL of water sample with 8 mL of lugol (1%, v/v) was conducted for 1 week. After this period, samples were decanted until a final volume of 2 mL was obtained. The identification was made by observation and quantification in a Neubauer camera through a light microscope to the genus level and was based on Bellinger and Sigee (2015) and Carter-Lund and Lund (1995). The enumeration was performed according to Lund et al. (1958) with at least 800 cells counted per Neubauer camera (each sample was recorded in 3 replicates).
Macrozooplankton quantification (Cladocera and Copepoda) was made by counting all adult individuals in each sample with a square grid. The identification was also taken to the genus level, based on Harding and Smith (1974), Amoros (1984), and Alonso (1996) guides.
2.5 Statistical analysis
Ecological data were analysed taking into account the phyto- and macrozooplankton communities (identification to genus level): diversity index (H'), richness (S), total abundance (N), relative abundance, evenness (J). The phytoplankton data was also used to assess the ecological quality ratio (EQR) as it is calculated for lakes and reservoirs (Van de Bund and Solimini, 2007). This ratio was calculated based on composition, abundance (% biovolume of cyanobacteria and IGA − Algae Group Index) and biomass ([Chlorophyll a and Total biovolume]) of phytoplankton community (INAG, 2009a). EQR represents the relation between the results obtained for the biological parameter used and the value expected for the same parameter in reference conditions of the waterbody. EQR use allows comparisons with ecological quality assessment methods applied in different countries and its values range between 0 (extreme degradation) and 1 (reference conditions).
To explore the relation between the planktonic communities and the spatial and environmental data, Detrended Correspondence Analysis (DCA) was performed. The gradient length of the first ordination axis was estimated to further decide what was the adequate ordination method for the multivariate analysis. For length gradients higher than 4 s.d., Canonical Correspondence Analysis (CCA) is recommended, while Redundancy Analysis (RDA) is more suited when the gradient length is less than 4 s.d. (ter Braak, 1995; ter Braak and Smilauer, 2002). According to this information, CCA (unimodal model) was considered the adequate multivariate analysis for the phytoplankton data (DCA axis length = 5.177). On the other hand, RDA (linear model) was chosen to analyse the zooplankton matrix once the length of gradient of the first ordination axis of the DCA was 1.645. After determination of the adequate ordination technique, Variance Inflation Factor (VIF) was calculated for all environmental variables in order to determine and exclude the redundant ones (VIF > 10, as suggested by Montgomery et al. (2012)). After this process, the CCA and RDA models were computed using the vegan package (Oksanen et al., 2019) in R-3.5.2 software (R Core Team, 2018) and graphed using the CANOCO 4.5® software. Permutations test were performed (999 permutations) to the CCA and RDA to assess the significance of the constrains (Legendre and Legendre, 1998) using the same package.
3 Results and discussion
The location of the study area in the Serra da Estrela Natural Park is shown in Figure 1. The studied ponds present different features, which result in distinct hydrological and ecological settings. Figure 2, along with Table 1, present the most relevant pond features: area, perimeter, length, width, elevation, connection to the local drainage network, connection to the groundwater flow, existence of sediment infilling and vegetation features. Regarding the surrounding vegetation, its main types according to Raunkiær life classification system (Raunkiaer, 1934) were hemicriptophytes (e.g. Festuca henriquesii Hack., an endemic species that occurred in all of the ponds), chamaeophytes, therophytes and phanerophytes. Although there was vegetation surrounding all ponds, P2 and P5 were the ones where plants where more abundant, with main species in common (Carex nigra (L.) Reichard, Juncus squarrosus L., Juniperus communis L., Nardus stricta L. and Potentilla erecta (L.) Raeusch).
P1, P3 and P4 do not have surface water or groundwater inlets, being hydrologically isolated. This means that the water level is mainly controlled by precipitation (as snow and rain) and evaporation, since the granitic bedrock is poorly weathered and fractured and, therefore, of very low permeability. P1 and P3 are also surrounded by undergrowth as woody plants (J. communis) and herbaceous vegetation (N. stricta, P. erecta, F. henriquesii, Leucanthemopsis pulverulenta (Lag.) Heywood, Rumex suffruticosus Gay ex Willk). P2 and P5 are characterized by abundant vegetation (helophytes) and coarse sediment filling. Water enters these ponds as runoff from several streams, groundwater flow and precipitation. During the drier months, namely, from July until September, when evaporation and evapotranspiration are higher, these ponds may dry out given their small depth and relatively large area, what happened to P2 in August and September (see Tab. 1).
Physical and chemical parameters data are presented in Table 2 and Figure 3. Dissolved oxygen was, in most cases, greater than 60% (of saturation) (Fig. 3b), as verified by several authors in similar alpine ecosystems (Girdner and Larson, 1995; Dumnicka and Galas, 2002; Martinez-Sanz et al., 2012). June and July were the months with the lowest pH and dissolved oxygen values, and higher water temperatures. The conductivity values are usually low in this type of ecosystems, nonetheless, the highest values in P5 may be explained by the impact of the use of de-icing salts in the local road. This practice can be responsible for soil and water salinization, for instance, P5 receives surface and underground flows from the road. Although this practice may have an environmental impact, in this study it does not seem to be a significant factor affecting the water ecological quality, neither its phytoplankton nor zooplankton diversity. Since this pond has water entry from four different points and has water run-off, this water renewal may dilute total salt content in the water during spring due to rain and ice melting. Nevertheless, it would be of interest the analysis of other compounds, other ponds without water renewal, and a continuous monitoring to prevent biodiversity loss and habitat degradation. Water temperature had different ranges according to the sampling month (Jun: 21.2–28.5 °C; Jul: 20.8–30.0 °C; Aug: 18.7–19.6 °C; Sep: 13.9–19.0 °C; Oct: 8.7–9.2 °C; Nov: 8.0–11.0 °C) and the turbidity was relatively low, ranging from 0 to 5.3 m−1. Phosphorous content was inferior to 0.04 mg/L (Fig. 3c). Regarding water hardness (3–8 mg/L CaCO3 in samples) (Tab. 2), it is considered to be very soft (<50 mg/L of CaCO3), which means that there is a very low dissolved mineral content (EPA, 2001), as expected in this type of alpine aquatic ecosystems. Overall ponds are in good chemical quality in most sampling periods, with values within the range of values for Good Ecological Potential in reservoirs (INAG, 2009a) (it is worthy of notice that there are no described values for small lentic waterbodies within the WFD for a better comparison). Besides, WFD recommends a five-class scale (bad, poor, moderate, good, high) but there is no national historical data and it is only possible to distinguish boundary values from Good to higher or lower (INAG, 2009b).
Trophic State Index (TSI) was calculated using chlorophyll a content for each pond in each sampled month (Tab. 2), and results were highly variable across the sampling months. However, when using the mean, values were close, with small variations between oligotrophic (TSI < 40; P2–34.59, P4–38.10 and P5–39.93) and slightly mesotrophic (40 < TST < 50; P1–41.78 and P3–40.18) (Carlson, 1977).
The results of the characterization of phytoplankton communities are presented in Table 3 and B1 from Appendix B. In general, the Shannon-Weaver diversity (H') was relatively low (0.87–2.47), as expected at high altitude ponds (Tab. 3). The richness of phytoplankton genera (S) ranged from 16 to 42, and evenness (J) values vary from 0.32 to 0.86. Although overall low, P2, P4 and P5 had higher diversity and richness values in comparison with the other sampled ponds. This was expected since these ponds had macrophytes, and it was already demonstrated that phytoplankton richness is higher in ponds with high abundance of macrophytes (Declerck et al., 2007). P2 had the greater richness and abundance what may be due to the high phosphorus content (Tab. 2), essential to phytoplankton proliferation. In August, P3 showed the highest Shannon-Weaver diversity value and evenness quantification, which means that the genera were similarly represented. The lowest value of diversity was recorded in November, also in P3 (Tab. 3).
The Ecological Quality Ratio (EQR) is an expression of biological assessments (phytoplankton in this study) that allows a comparison of ecological quality status independently from the ecological assessment method used. The ecological quality ratio, here calculated based on composition, abundance and biomass of phytoplankton community (INAG, 2009a), was higher in October and November and the poorest water quality was observed in June, except for P2 that was in July (Tab. 3). The lowest values of water potential ecological quality were very close to the limit value for good ecological quality; however, a moderate ecological quality was the final classification. It is worth reference that the EQR scale is supposed to be expressed using a numerical scale between zero and one (0–bad; 1–high). However, in Table 3 some values are higher than one. In fact, this method is described and used for heavily modified waterbodies but, in this study, it is being applied to alpine ponds. These results demonstrate that the current EQR scale is not fit to be applied to alpine ponds as expected. Since these are usually located in remote geographical areas with overall harsh environment and low anthropogenic disturbance (Körner, 2008), alpine ponds are normally in a pristine state although having harsh abiotic features, which originate overall unique biotic communities (Hinden et al., 2005; Boggero and Lencioni, 2006). Therefore, it is necessary to adapt the current ecological quality indexes to better fit ecosystems with extreme environmental conditions such as the alpine ponds here studied. Successful EQR reference values and class boundaries were already established and implemented in the WFD for alpine and peri-alpine lakes of Central Europe (Kaiblinger et al., 2009; Wolfram et al., 2009). Albeit not very precise, indexes as the Brettum Index for Austria and Slovenia and the German Index (PSI) are sufficient to roughly estimate the quality status of peri-alpine lakes accordingly to Kaiblinger et al. (2009). Class boundaries for chlorophyll a content were also established for those lakes by Wolfram et al. (2009). Although these class boundaries were not developed for Mediterranean alpine ponds, cross-checking the mean Chl a for the studied ponds with the boundaries established for shallow alpine lakes of Central Europe (Wolfram et al., 2009) allows a classification as "Good" or higher for all studied ponds. Further research should focus on adapting the indexes made for alpine lakes of Central Europe and make them applicable to Mediterranean alpine ponds.
Phytoplankton dynamics for each pond is presented in Figure 4. In early sampling months (mostly June and in some cases July), the phytoplanktonic community was dominated by Cyanobacteria, except in P1 where the community was dominated by Eustigmatophyceae. However, the CCA analysis (Fig. 5) shows a correlation between the groups Cyanobacteria and Eustigmatophyceae, and temperature values and ammonia content. Indeed, it has been already demonstrated that cyanobacteria species, in general, increase their growth and development at higher temperature when compared to other algal groups (Dokulil and Teubner, 2000; Reynolds, 2006; Vincent, 2009). Therefore, elevated water temperatures may be a factor driving the increase of cyanobacteria abundance that occurred in the studied ponds, especially during summer. Besides, some inorganic nitrogen forms, such as ammonia, are reported to also favour the increase of cyanobacteria abundance (Dokulil and Teubner, 2000; Dai et al., 2012), thus being also a factor contributing to the dynamics of cyanobacteria portrayed. Another factor for the increase of cyanobacteria in this period is their ability to produce UV-screening compounds, what may be a competitive advantage in alpine ponds that are under high UV radiation (McGowan et al., 2008).
In mid-summer (August and September) there was a general increase in the flagellated genera (Euglenophyceae) and in some ponds the green microalgae (Trebouxiophyceae) (Fig. 4). In alpine lakes and ponds, during ice-free periods, usually there are two phytoplankton abundance peaks: after de-icing in Spring and in Autumn, where Cyanobacteria (and some diatoms) and dinoflagellates dominate, respectively (McKnight et al., 1990; Winder et al., 2003; Tiberti et al., 2013). However, in the study, there was a relevant increase of Dinophyceae on P1 in August and September and there was no Autumn peak of dinoflagellates as could be expected for alpine ponds. Indeed, as the water temperature decreases, there is an increase in Diatom (Bacillariophyceae) and Cryptophyceae abundance, with exception of P3. These groups are usually found in colder waters and are expected to increase their abundance in October and November (see in Fig. 4 for P1, P2, P4 and P5), before the water freezes (Figueiredo et al., 2006; Bellinger and Sigee, 2015). Indeed, these taxa are able to grow under weak light and low water temperature conditions when compared to other microalgae groups (Kumar et al., 2012). The presence of phytoflagellates, as Cryptophyceae, is reported to be sporadic and intermittent with rapid changes in abundance (Dokulil, 1988). The phytoplanktonic community pattern of P3 appears to be the more distinct. In October and November, there was a growth in Chrysophyceae abundance that, along with coming green microalgae (Trebouxiophyceae), dominated the community in that period. This pattern is unusual and is not in accordance with the green algae ecology, where they are dominant or codominant in early or mid-summer (Bellinger and Sigee, 2015). Phytoplankton growth rates in alpine ecosystems respond rapidly to changes in nutrient availability and other environmental conditions (Gardner et al., 2008) and can explain the atypical community dynamics of P3. For example, P3 nitrate content was lower than in other ponds, and it has already been shown that nitrogen, as well as phosphorus, can be a limiting nutrient for primary productivity (Kratzer and Brezonik, 1981). Lower nitrogen concentrations may lead to a lower phytoplankton abundance and altered phytoplankton species dynamics (Maberly et al., 2002). It is known that chrysophytes typically do well in low nutrient environments (De Hoyos et al., 1998) and are able to flourish in low DOC systems (Vinebrooke and Leavitt, 1999; McMaster and Schindler, 2005), thus explaining the atypical pattern perceived.
Figure 5 shows a CCA analysis of the phytoplankton data against the environmental variables analysed. After analysis it is possible to see that June samples seem to be marked by increased CDOC, TP and NH4 (Fig. 5). Favoured by the increase of these values and in association with the summer period it is possible to see also that the communities differentiate, having higher concentrations of Xanthidium sp., Ceratoneis sp., Spirotaenia sp., Cocconeis sp., Glenodiniopsis sp., Nitzschia sp., Thalassiosira sp., Eudorina sp., Ulothrix sp., and Tetraedriela sp. and Cyanobacteria. In the right side of the plot, it is also possible to see an accumulation of the P2 samples, connected mainly with higher CDOC and with TSS for autumn samples. P5 had the higher amounts of total suspended solids for July, what was associated with noticeable higher presence of Gymnodinium sp. and Rhodomonas sp. For last, there seems to be an aggrupation of samples from P3 in association with higher BOD5, even though the values are not much different between ponds.
The macrozooplankton community analysis is displayed in Table 3 and B2 (Appendix B), Figures 6 and 7 for the five ponds along the sampling period. P4 shown the highest Shannon-Weaver diversity value (1.60) and P5 the highest evenness value (1.00) (Tab. 3). Although the development of macrophytes may have a positive effect on zooplankton biodiversity, as already shown for shallow lakes (Van den Berg et al., 1997) and shallow interconnected ponds (Cottenie et al., 2001), however not verified in our data, once diversity values were highly variable. Nonetheless, diversity, richness and evenness values were overall low, what is expected in this kind of high-altitude environments (Tavernini, 2008; Moreira et al., 2016) due to the adverse conditions. Indeed, the case-study ponds are isolated and, therefore, there is lower probability for colonization to occur (Scheffer et al., 2006; Moreira et al., 2016). However, it is possible to notice the usually lower diversity values in September. Higher summer temperatures increase water evaporation in the ponds (P2 was completely dry in August and September), and the instability of the waterbodies may have caused an impact in the overall communities composition (Wissinger et al., 2016). In fact, water volume may have a major influence in species composition in high-altitude waterbodies. Seasonal patterns for zooplankton communities are usually well defined and its turnover is often consistent from year to year (Kratz et al., 1987; Hu and Tessier, 1995; Rettig et al., 2006). Regarding the Cladocera order (Fig. 6), a predominance of Chydoridae genus (Acroperus, Alona and Chydorus) were observed in the samples. This is considered to be a constant pattern in shallow wetlands and high-altitude temporary ponds (Coronel et al., 2007; Kamenik et al., 2007; Moreira et al., 2016). There are several studies suggesting that Daphnia abundance is intrinsically correlated to an increase in water temperatures of lakes (Wolfinbarger, 1999; Benndorf et al., 2001), however, in this study was not possible to assess this seasonal trend. Moreover, in many other studies no correlation between the abundance of Daphnia and water temperature was recorded (Winder and Schindler, 2004; Rettig et al., 2006). For instance, the abundance peaks of Daphnia varied from pond to pond, occurring either in June and July, in P1 and P3, and in October, in P5. This distinct pattern in relation to temperature may be due to specific responses to local abiotic and biotic factors (Winder and Schindler, 2004) or even to water volume of the ponds, as already described. Nonetheless, temperature may influence the distribution of macroinvertebrates (Oertli et al., 2008) and amphibians (Newman, 1998) (top predators in fishless lakes and ponds), and the presence of these organisms may pressure large-bodied zooplankton species through predation, thus influencing overall zooplankton distribution and species richness (Anas et al., 2015). About Copepoda, Cyclopoida spp. was the dominant group throughout all sampling period for most ponds. However, the dominance of Calanoida in alpine lakes seems to be recognized worldwide (Jacobsen and Dangles, 2017). The dominance of copepods in almost all sample periods (except for October and November) may be due to their higher tolerance to the UV radiation, that is stronger in the summer. In fact, it was already described that in copepods, blue light screening carotenoid concentration seems to be higher with higher light intensity and lower temperatures (Byron, 1982). Besides, copepods that are under high UV radiation and at higher altitudes show higher concentration of mycosporines and mycosporines-like amino acids (Tartarotti et al., 2004; Persaud et al., 2007) and carotenoid pigmentation (Byron, 1982) in comparison with cladocerans, what thus may explain the higher dominance of copepods in the study sites, except for the autumn periods, with the decrease of UV radiation intensity. Several factors mentioned may explain the zooplanktonic dynamics shown, but one cannot exclude the possibility that heterogeneous distribution of zooplankton in the ponds due to wind, macrophytes distribution or even distribution in patches could influence some of the variations in zooplankton density registered, even though samples were taken in different sites in each pond to minimize this interference.
Regarding the macrozooplankton RDA analysis (Fig. 7), total phosphorus and chlorophyll a content were the only significant constrains assessed by the permutation test. There seems to be an association between most cladocerans genus found (Daphnia, Alona, Bosmina, Diaphanosoma and Simocephalus) with higher phosphorus content. In a study regarding 71 Danish lakes (mostly shallow), Jeppesen et al. (2000) found an increase in small-bodied cladocerans with an increase in TP content. Nonetheless, when cyprinids were removed from those lakes, the reduction of fish predation promoted a major abundance of average sized cladocerans. In the studied alpine ponds, such predation pressure was not so strong once the ponds are fishless, and the only predators were amphibians and macroinvertebrate larvae, thus leading to a dominance of normal sized cladocerans. Regarding to copepods, our data also suggests that cyclopoids dominate in environments with higher TP and chlorophyll a content. A similar shift from calanoids to cyclopoids along a TP gradient was also described for the same shallow lakes in Denmark (Jeppesen et al., 2000). Besides the relations with TP, there is not any other clear pattern connecting the environmental variables measured with the zooplankton communities sampled. This lack of clear influence of the environmental variables on the macrozooplankton communities' composition may indicate their inadequacy as biological indicators of water quality in Mediterranean alpine ponds. Nonetheless, zooplankton communities may respond to other water physical and chemical parameters not tested in the present work, not excluding them as possible bioindicators of specific pollutants in these extreme systems. Besides, as only macrozooplankton was tested, a necessity arises to test other specific groups of zooplankton as bioindicators for alpine ponds (e.g. rotifera).
Even though it was not possible to form distinct groups in the redundancy analysis, the lack of patterns was already expected since these ponds are very remote ecosystems, where even the smallest environmental variations may dictate a different biological pattern.
It is of agreement that cladocerans are usually the most dominant forms of macrozooplankton in alpine ponds (Rautio, 2001), what was not observed in this study (Fig. 6). In a study conducted by Rautio (2001) in treeline alpine ponds, it was possible to see that copepods appeared first in the ecological succession, right after ice melting, while cladoceran appearance was restricted do mid-late summer, when water temperatures reached 15-20 °C. However, this trend was not found as the limnetic conditions are highly variable, with cladocerans appearing at different months in different ponds. Besides, copepods highly dominated macrozooplanktonic communities in these ponds, contrarily to what was first expected. This may be due to the high ability of copepods to tolerate low food concentration and temperature when compared to cladoceran species (Muck and Lampert, 1980; Rautio, 2001). In addition, in limnetic systems, copepods are generally richer in nitrogen while cladocerans are richer in phosphorous (Sommer and Sommer, 2006). Thus, the overall limitation in phosphorous content of the studied ponds (Fig. 3) may be modulating the zooplanktonic community dynamics towards higher relative abundance of copepods over cladocerans.
Physical and chemical parameters and Trophic State Index (TSI) values classification for chlorophyll a (TSI – Chl a), for each sampling period of each pond. *BDL – Below Detection Limit; O – Oligotrophic; M – Mesotrophic; E – Eutrophic. Pond 2 was dry during August and September sampling period.
Fig. 3
Line graphs representing the evolution of a) pH; b) dissolved oxygen (%); c) ammonium (mg/L); d) nitrates (mg/L) and e) total phosphorus (mg/L) content for each sampling month. The lines represent the studied ponds. The grey limit represents range values for Good Ecological Potential: 6 ≤ pH ≤ 9; 60% ≤ O2% ≤ 120%; TP ≤ 0.13 mg/L ; NH4 + ≤ 1 mg/L; NO3 − ≤ 25 mg/L.
Diversity Indices (DI): Shannon-Weaver Index (H' − diversity), Pielou (J − Evenness) and richness of taxa (S) for phytoplankton and zooplankton communities in the sampling period of each pond. EQR stands for Ecological Quality Ratio based on phytoplankton composition and abundance.
Fig. 4
Relative abundance (%) of major algae groups for the sampling period of each pond. Phytoplankton richness values are represented in the secondary axis. For pond 2, there is no data for August and September due to the totally dryness of the pond. For density results, see Table B1 from Appendix B.
Fig. 5
Canonical correspondence analysis between environmental variables and phytoplankton composition. CCA axis 1–8.04%, eigenvalue = 0.228; CCA axis 2–6.43%, eigenvalue = 0.182. For taxa abbreviation see Table A1 from Appendix A.
Fig. 6
Relative abundance (%) of macrozooplankton − Cladocera and Copepoda groups for the sampling period of each pond. For pond 2, there is no data for August and September due to the totally dryness of the pond. For density results, see Table B2 from Appendix B.
Fig. 7
Representation of a redundancy analysis between environmental variables and macrozooplankton composition. RDA axis 1–51.1%, eigenvalue = 658.43; RDA axis 2–1.90%, eigenvalue = 24.42. For taxa abbreviation see Table A2 from Appendix A.
4 Conclusion
Overall, the studied ponds presented a good chemical and physical state in almost sampling periods. These were also in good ecological state according to phytoplankton metrics from the Water Framework Directive approach to artificial water bodies (reservoirs). Trophic state was variable during the study period, but normally the ponds were classified by an oligotrophic system according to chlorophyll a concentration. Cyanobacteria, Euglenophyceae and Trebouxiophyceae were the most representative groups of phytoplankton in the studied alpine ponds and Cyclopoida was the most abundant from macrozooplankton group. The different seasonal dynamics of this study may be explained by the severe and extreme abiotic conditions of Serra da Estrela ponds. Although this study did not show a clear correlation between environmental variables and macrozooplankton besides the shifts caused by the total phosphorus content, it does not exclude the hypothesis of macrozooplankton community as bioindicator of water quality assessment and trophic state of alpine ponds and lakes. However, further studies should be carried out with the intention of perceiving which other environmental variables (such as sodium chloride, calcium chloride, depth, organic matter, ice cover, sediment type) may modulate the macrozooplankton distribution in extreme environments such as alpine ponds. In future research, it would be also important to study other biotic matrices (e.g. macroinvertebrates, aquatic plants; invertebrate predation; competition) to test the possible use as tools to assess water quality of these aquatic ecosystems. These factors are likely to be a source of variation in ecosystems' structure and composition and, therefore, in its food web. It would also be important to perform a continuous monitoring of these aquatic ecosystems in terms of anthropic threats and global climatic change.
Sara Antunes is hired through the Regulamento do Emprego Científico e Tecnológico − RJEC from the FCT program (CEECIND/01756/2017). This work was supported by National Funds (through the Portuguese Science Foundation) and by the European Regional Development Fund (through COMPETE2020 and PT2020) by means of the research project ReDEFine (POCI-01-0145-FEDER-029368), and by the Strategic Funding UID/Multi/04423/2019 through national funds provided by FCT − Foundation for Science and Technology and European Regional Development Fund (ERDF), in the framework of the programme PT2020, and by the project. J. Espinha Marques was supported by funds from the European Union through the European Regional Development Fund, framed in COMPETE, 2020 (Operational Programme for Competitiveness and Internationalization), through the project ICT (UID/GEO/04683/2013) with reference POCI-01-0145-FEDER-007690.
Appendix A
Abbreviations of phytoplankton genus used in the phytoplankton communities CCA analysis.
Abbreviations of zooplankton genus used in the zooplankton communities CCA analysis.
Appendix B
Density in individuals per litre of phytoplankton families in each of the studied ponds for each of the periods sampled.
Density in individuals per litre of macrozooplankton genus in each of the studied ponds for each of the period sampled.
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All Tables
Pond physical and morphometric features.
Physical and chemical parameters and Trophic State Index (TSI) values classification for chlorophyll a (TSI – Chl a), for each sampling period of each pond. *BDL – Below Detection Limit; O – Oligotrophic; M – Mesotrophic; E – Eutrophic. Pond 2 was dry during August and September sampling period.
Diversity Indices (DI): Shannon-Weaver Index (H' − diversity), Pielou (J − Evenness) and richness of taxa (S) for phytoplankton and zooplankton communities in the sampling period of each pond. EQR stands for Ecological Quality Ratio based on phytoplankton composition and abundance.
Abbreviations of phytoplankton genus used in the phytoplankton communities CCA analysis.
Abbreviations of zooplankton genus used in the zooplankton communities CCA analysis.
Density in individuals per litre of phytoplankton families in each of the studied ponds for each of the periods sampled.
Density in individuals per litre of macrozooplankton genus in each of the studied ponds for each of the period sampled.
All Figures
Fig. 1
Serra da Estrela Natural Park geographical setting and location of the study area.
|In the text
Fig. 2
Drainage network of the studied ponds.
|In the text
Fig. 3
Line graphs representing the evolution of a) pH; b) dissolved oxygen (%); c) ammonium (mg/L); d) nitrates (mg/L) and e) total phosphorus (mg/L) content for each sampling month. The lines represent the studied ponds. The grey limit represents range values for Good Ecological Potential: 6 ≤ pH ≤ 9; 60% ≤ O2% ≤ 120%; TP ≤ 0.13 mg/L ; NH4 + ≤ 1 mg/L; NO3 − ≤ 25 mg/L.
|In the text
Fig. 4
Relative abundance (%) of major algae groups for the sampling period of each pond. Phytoplankton richness values are represented in the secondary axis. For pond 2, there is no data for August and September due to the totally dryness of the pond. For density results, see Table B1 from Appendix B.
|In the text
Fig. 5
Canonical correspondence analysis between environmental variables and phytoplankton composition. CCA axis 1–8.04%, eigenvalue = 0.228; CCA axis 2–6.43%, eigenvalue = 0.182. For taxa abbreviation see Table A1 from Appendix A.
|In the text
Fig. 6
Relative abundance (%) of macrozooplankton − Cladocera and Copepoda groups for the sampling period of each pond. For pond 2, there is no data for August and September due to the totally dryness of the pond. For density results, see Table B2 from Appendix B.
|In the text
Fig. 7
Representation of a redundancy analysis between environmental variables and macrozooplankton composition. RDA axis 1–51.1%, eigenvalue = 658.43; RDA axis 2–1.90%, eigenvalue = 24.42. For taxa abbreviation see Table A2 from Appendix A.
|In the text
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text:
Vermilion Falls
Stacy and Dylan drove out to the house this morning to join April, Jesse, Jim, Erin, and I out to Vermilion Falls. We hopped in the car and took off towards Crane Lake. Its a bit of a drive, and since we took the back gravel roads which are pretty sloppy with all the snow melting it was even a bit longer. We got to the road heading towards the falls only to find it hadn't been plowed yet. We put the vehicles in 4-wheel drive and continued down the 4 mile road. When we got to the "drive way" into the parking area it was even more covered in snow and was heading up a hil, so we parked the cars and began our hike there.
We were hoping to catch the ice breaking up and being forced through the narrow gorge, but when we got to the river we found it already open. It still is a fun place to visit. There is a ton of water rushing through there. We took some pictures and had lunch on a picnic table.
All throughout our day in at the falls we were having mini snowball fights. The snow was the perfect consistency for making snowballs. Dylan was a fierce competitor and was always ready for a battle. After we finished eating Jim had the idea of making a snowman. It didn't take too long and we had a very respectable snowman to greet any visitors in the next couple of days. I don't know how long he'll last, but as long as the skies continue to be covered with clouds and the temps stay in the 30's it could be some time before he withers away.
We then headed back to the cars and drove to Orr where we filled our car with gas and our tummies with A&W root-beer floats. They sure are tasty, but make it quite difficult to drive and work the spoons filled with the bubbly ice cream to your mouth. We headed back to the house where we relaxed and had some dinner.
It sure was a nice way to spend a Saturday.

subset: commoncrawl


text:
Buffalo provides Data Recovery services. Read about it here.
A pair of Link Station Pro 1TB LS-1000GL units.
So I saw the little marketing diagram showing multiple Linkstation Pros and their ability to back up to each other. I made an incorrect assumption and now wonder if there is a way to achieve what I want...
I have a pair of 1TB Link Station Pro units. I'd "simply" like them to stay sync'd. I'd even be happy with just a once-a-day one-way copy. I configured one to back-up to the other, but it creates a new entire backup image in a new folder every day. What I want is at the end of each day (or whenever the daily backup runs) both units will have identical contents.
Another way to say this is that I want to create a sudo "mirror" or RAID 1 array out of my 2 units.
I could mount both on my computer and use a script to sync between them. However, I want a solution that is not dependant on any of my computers.
You cannot create a RAID array between the two units but since they are the same model you should be able to back one up to the other.
What you want to do is setup a backup job like you had it doing before, but istead of doing a "Normal" backup would want to use one of the other four Modes. Here they are:
Saves as "yyyymmddhhmm\sourcename\data". Makes a new folder for each backup.
Saves as "_backups\sourcename\data". Does a complete backup every time, if a file is on the destination that is not on the source, it will not be deleted.
Overwrite Backup (Complete/Differential):
Saves as "_backups\sourcename\data". Does a complete backup every time, if a file is on the destination that is not on the source, it will be deleted.
Overwrite Backup (Append):
Saves as "_backups\sourcename\data". Does a complete backup the first time, subsequent backups only send the changes. If a file is on the destination that is not on the source, it will not be deleted.
Overwrite Backup (Differential):
Saves as "_backups\sourcename\data". Does a complete backup the first time, subsequent backups only send the changes. If a file is on the destination that is not on the source, it will be deleted.
Pretty much Complete backups do a complete back up everytime (overwriting files). Append backups will not delete a file that has already been backup, if that file was deleted from the source (other LS), Differential backups will delete that file during the backup.
Kevin, thank you very much for this detailed reply. So, if I understand correctly, the "Overwrite Backup (Differential)" mode is the closest to what I want. It wil not create completely new backup folders every time. Instead, it will always write the backup to the same folder. Only changes get synced to the backup. If files are deleted from the "source", they are also removed from the backup location.
This is ALMOST what I want. It is what I want except for the fact it puts the backed up files in a folder (_backups). I literally want the two units to appear to be identical after a backup. That is I could swap IP addresses and my users would never know.
It would be great to see a "mirror" option.
Thanks again!
Same here! I want to achieve the same thing on my 2 LinkStation Quads 4T
I am trying to create a 'syncronized' backup between primary and secondary Linkstations. I will use the "Overwrite Backup (Differential)" option to accomplish this. However, I do not want the backup Linkstation to have the "_backups" directory name. I just want an exact replica of my Primary Linkstation's Share folder directory structure in the Secondary Linkstation's Share folder. When I uncheck "Create a Folder Inside of the Backup Target", it gives me the strangest warning dialog box. It is in English, but I have no idea what it means! It says:
"Create folder to identify backup source option isn't specified. In this case, estimated result can't be obtain due to Backup Operation Mode. Refer to Help and backup test is strongly recommended. Will you continue?"
I click continue, and the initial backup works fine. The question is, will the subsequent Differential backups work correctly (backing up new and changes files, and deleting removed files)? Or, does the "_backup" destination folder need to be there for some reason?
I want the same thing but you're both ahead of me. I haven't been able to make my Linkstation Live unit back up to my identical Linkstation Live at all. I've read KB#000120 however I've had zero success.
1) There should be a way to create a backup mirror
2) The backup should allow a remote backup where the remote is behind a firewall and not exposed to the entire world.
3) Such a backup should be very easy to create as it's a often asked for feature and currently leaves users disappointed 98% of the time.
I wrote to Buffalo about this issue twice asking for help but never got a response from their support. They promised a response in 48 hours but it's been weeks so I don't think one is coming any longer.
The units are soooo close to being really valuable units, but in their current state they're nothing more than expensive local storage.
Wondering if any of you guys found a solution to this--i want to do the same thing: keep a mirror of my data in two locations. I know how it can be done with rsync, but i'd rather not void the warranty to get the ssh/rsync access on the Linkstation.
I do it now with local USB drives and cygwin, but it seems like the Linkstations are so close to being able to do it themselves...i'd like to know before investing the moula. ;-)
I sent several emails to technical support but didn't get a reply to any of them. I have not been able to make it work. My backup unit is sitting on the floor by my desk doing me no good whatsoever. I've been mislead and conned. I will never suggest Buffalo to anyone as they misrepresented their product and offered zero support when given an opportunity. They have a well known problem effecting many of their customers and they have decided to ignore the problem and hope it goes away. I'm disgusted with them as a company.
I found a solution to this battle ages ago. I ran
rsync -av --log-file=/cygdrive/d/LOGS/rsync/rsync.log /cygdrive/ddrive/ /cygdrive/edrive
Note that the source folder has a trailing slash, while the destination folder has no trailing slash. ddrive was how I mapped my primary linkstation and edrive was how I mapped my secondary linkstation. Note that for two way sync, you may need to run the reverse as well after the above command, which is:
rsync -av --log-file=/cygdrive/d/LOGS/rsync/rsync.log /cygdrive/edrive/ /cygdrive/ddrive
Now if you are interested in just ensuring that drive2 is a mirror of drive1, where any deletes in drive1 should also happen to drive2, just add the "--delete" option while running rsync, however I do not recommend automating the deletes.Example:
rsync -av --delete --log-file=/cygdrive/d/LOGS/rsync/rsync.log /cygdrive/ddrive/ /cygdrive/edrive
I have this running under CYGWIN on my home server and works mighty well. For those that are looking for an easier solution, I have Vice Versa Pro. This product is well worth the money.
I see there is a Windows version of the rsync command. Do you run this using task scheduler? How are you mapping the remote drive when it's off the local network behind a firewall? I can use Dynamic DNS but I can't use a port name in a mapped drive can I? And the only security with an open port would be the security on the Buffalo drive. Is that robust enough? Would I need to use a VPN instead of an open port?
cdsJerry, here's what i do: i keep a buffalo at home and just a USB drive at work as an off-site backup. I have cygwin installed on both systems which includes rsync but also can turn your Win system into an ssh host. Then you can use the rsync/ssh facility to connect over the internet to update/mirror.
The problem i'm having is that my initial rsync for backup is behaving strangely. That is, i rsync my "My Documents" folder to my Buffalo LS, and then that mirrors to my work system. That first step used to work fine with a USB drive, but now that it's using a mapped drive to the LS some files always update.
Right--only some files. I do an intial -a rsync, and then the same files seem to need to be transferred over and over, rather than just new files. There has to be something particular to those files, but then these files didn't cause a problem when it was a different drive.
Not expecting direct support here, but just hoping someone has an idea...
I guess it's good not to expect support because Buffalo doesn't support anything as near as I can tell. My two units are still sitting on the floor behind my desk because I've never been able to make them work the way Buffalo claims they work.
I'd LOVE to mirror one of them to another one that's located behind a firewall at a different location. I can do the VPN thing but Buffalo insists it needs to be a WAN IP and won't work with a LAN. Buffalo SO misrepresents this product.


text:
I am searching for an open source hotel booking system, preferably written in Java.
3Welcome to Software Recommendations Stack Exchange! We will need much more information to give good recommendations here. Please take a look at What is required for a question to contain "enough information"? Then please edit your question and see if you can incorporate some of these improvements. Basically just need more details on what features your require. – Nick Wilde Jul 30 '14 at 5:30
2So, you run a hotel, and you want to allow clients to book online, right? Do you already have a website? If yes, what language is it written in, PHP, JSF, JSP? Do you need to connect with a third-party commercial website for money transactions? If yes which one? – Nicolas Raoul♦ Aug 15 '14 at 2:26
Keep an eye on softwarerecs.stackexchange.com/questions/17550/… – Mawg says reinstate Monica May 19 '15 at 8:35
Maybe someone will add system written in Java, but I'd like to show you there are such a systems available as plugins/extensions of popular CMS (content management system) platforms. They are not necessarily free, but they are open source (so you get source code after purchase)
CMS Wordpress - search - example found: Booking System (Booking Calendar)
Hopefully this shows you the idea.


text:
Welcome Amazon Employees!
Thank you, Amazonians, for helping Arlington families build stronger futures! AHC Inc is grateful to be one of the local nonprofit partners chosen to participate in Amazon's Employee Matching Campaign. Your support for affordable housing and education opportunities is changing lives. Thank you!
Housing + Education = Success
AHC Inc. develops and preserves housing that is affordable to low- and moderate-income families, individuals, and senior citizens. With more than 40 years of community experience, we know first-hand that an affordable roof overhead is the first step in family stability.
Our extensive education and social services programs build on that foundation.
Our super power? AHC works right where people live. Our programs are consistent and accessible. Our staff are trusted resources. Children grow up in our programs and thrive. That's why we believe "Housing + Education = Success."
Our Track Record
- 100% of AHC's students graduate from high school.
- Nearly all go to college and are the first in their families to achieve this milestone.
- Last year, our high school grads earned more than $600K in scholarships.
- 80% of AHC's college students are persisting in college or have graduated. This compares to 74% of U.S. college students with college-educated parents and 56% of first-generation students.
- Click here for our most recent "Report Card," an overview of our programs for residents.
Donate Now and Double Your Impact
Every dollar you donate goes directly to the children and families we serve. Your support helps us provide year-round educational programming, social services programs, health and wellness workshops, financial capability classes, eviction prevention services and more.
Amazon Smile Wish List
Provide much-needed education tools for AHC's youth. Check out our "Wish List" on Amazon Smile.
Volunteer: Help Build Strong Futures
Volunteer with AHC and change a child's life. In just an hour a week, volunteers inspire, mentor and connect with youth in our programs from kindergarten through high school. Learn more.
We also offer lots of one-time volunteer opportunities, from participating in a career fair to bringing your dog to our "Read with Dogs" program for our elementary students. Learn more.
Interested in a group volunteer opportunity? Contact Laura Jackson at 703-486-0626 x 1107 or firstname.lastname@example.com.
Recent News
- Students Given Opportunity to Network With Wide Array of Those in the Field of Technology, Sun Gazette, 8-8-19
- Amazon's Latest Donations to Support Housing and Homelessness, Amazon One Day Blog, 7-12-19
- They All Kind of Live Through Me: What It Means to Be the First Person in Your Family to Go to College, Washington Post, 6-16-19
- AHC Program Supports Arlington Youth to Graduation and Beyond, Sun Gazette, 6-17-19
- AHC celebrates 24 first-generation college bound high school graduates, WDVM, 6-26-19
- AHC Inc., Episcopal Church of the Resurrection and City of Alexandria Break Ground on $48M Affordable Apartment Community in Alexandria, VA
- Local Leaders Kick Off $100 Million AHC Inc. Affordable Housing Development in Arlington


text:
August, 2011
By: Amy Aiello
I think I may have had a little bit too much fun talking with Tim and Dan of OK GO, and I even feel a bit guilty for taking so much of their time (a full half hour chat!). I blame both of them for being so easy and fun to chat with, and throwing questions right back to me to make this an all around interview. I even got to catch up with Dan's wife after the interview was over with (who, by the way, is a very sweet, lovely and talented woman).
We spent a bit of time talking about the important stuff: pancakes vs waffles, gummy bears vs apples, chocolate or tart candies (like sour patch kids). The guys gave me a tip to try this Pink Berry place out in LA next time I venture out there (think TCBY, Chicagoans old enough to remember that frozen yogurt haven).
TIM: I'm a huge pink berry nut. I don't know if you have pink berry in Chicago; it's like the number one yogurt place in LA. I get chocolate pink berry with cap'n crunch and oreo.
CMG: Does it still cut the roof of your mouth?
OK: it sure does! The taste is worth it
CMG: Berry berry or regular?
TIM: Regular. I liked the berry one when I was a kid. I think kids are drawn to the berries because it's more colorful; more fruity, more sugar.
But the progression of our half hour chat was all over the board. Tim is a great story teller:
TIM: We as a band love the movie casino. We once had a van in the UK that we traveled in that had a VCR in it but only two video tapes. One was Texas Chainsaw Massacre, and the other was Casino. I think watched casino every day pretty much from beginning to end almost two weeks straight. We tried to watch Texas Chainsaw Massacre, but it did not fit the vibe. We always ended up saying, "Let's just watch casino."
CMG: REALLY? That's kind of surprising.
TIM: Well, Casino's violent, but there's also this pretty amazing storyline to it, and pretty great acting. I recently got to meet Robert DiNiro. I was pretty aside myself. Dan and I did this sort of reinterpretation of this scene in Casino that's online. I wanted to say, "I've played you before…" it wasn't appropriate. He didn't want to talk to me. We had this meeting with an architect in London whose next meeting was with Robert DiNiro. As we were leaving he was walking in, and he just wanted to get to his meeting. We had very similar beards.
Are you smiling or even confused at the sheer randomness of this interview yet? We chatted about places to go when the band comes back to Chicago, their hometown, and found ourselves talking about jobs in the service industry.
DAN: I was a bartender for about 6 years before the band was busy enough. I actually when I left, I don't know if I can show this to you (shows tattoo).. as an ode to bartending I got a cocktail sword tattooed on my shoulder which says I'll never go back. No. But… I loved bartending. It helps you; it gives you more opportunities to encounter and deal with on edge and pretty crazy people. So when you finally get into relationships with people who aren't so crazy, you're usually better at it. I feel that I can be in relationships with people in a better way because I've dealt with so many nasty drunks.
CMG: How has success played a role in your personalities and shyness/outgoingness?
TIM: I started as a pretty shy kid, which still kind of comes out in certain situations, but… I got into theatre really early on. I sort of learned how to play other characters to get over my shyness. Now I don't know who I am anymore. Yeah. Hundreds of thousands of psychologists bills later…
I think what we've done has helped grounded us as people. I don't think anything we've done has changed us. I've known dan since I was 18, and I'm 35 now. I've known Damian since I was 11. We're all pretty much the same. No one's really changed all that much.
DAN: I think we're getting better. I think we're getting better looking. I was an ugly kid. And at 24? UGLY!!! We had more hair, didn't really know what to do with it… And Tim. Tim looks better than he ever has. Tim is a HOT dude. You're hot right now.
TIM: Thanks Dan! Dan has always been a very beautiful man. Since day one; since the first time I ever laid eyes on him. We're sort of getting into a blind beauty right now.
TIM: We just shot this video where we had to wear these one piece unitards. We had to wear dance belts. I don't know if you know what dance belts are; they're basically like male thongs.
CMG: Well it's fun for the ladies to look at; you know, like the ballet
TIM: yeah but they have dancer bodies. We have like rocker drink beer bodies.
CMG: But you're on a diet though, right?
DAN: Yeah you look good. You look hot!
Check out the latest video from OK GO, and stay tuned to their website for their latest acts of randomness.
In the year since EMI issued OK Go's acclaimed third album, Of the Blue Colour of the Sky, the Los Angeles quartet has gone from being a rare young light on a major label to arguably the world's most bleeding edge independent outfit. You probably know the bit about the treadmills by now (if not, you can read Ira Glass's account below), but one can authoritatively say that those trusty treadmills shot the band into both better health and a technicolor zone beyond the hoary indie-versus-major debate.
Billboard called them "trailblazing," the head of Apple's marketing said they were "the first post-internet band, the first band to use the internet as a medium of art, not just commerce." BusinessWeek praised their new model of "proactive creative types… looking beyond traditional parameters to get support for their work." OK Go's project is one of the modern age, of unlimited possibility, where infectious songs, inventive videos, surprising live shows, and an articulate, forward-thinking back-end combine into a total work by a defiantly do-it-yourself band without a shoestring budget. The band says they just like "making stuff."
In a series of surprising partnerships, companies like State Farm, Samsung, Flip Camera, and Range Rover have stepped into the role that major labels once occupied: investing in the band's berserker videos (like the 18-million-views-and-growing /UK-MVA-Best-Rock-Video-winning Rube Goldberg-esque masterpiece for "This Too Shall Pass") and sold-out tours. Moreover, the band have emerged with an unprecedented level of independence, simultaneously bypassing a dying industry's gate-keepers with creative aplomb and forging the kind of three-dimensional band/audience relationship only fantasized about by social networking consultants.
The band's very public dispute with EMI about fans' rights to embed the band's videos landed them square in the crosshairs of contemporary culture. Kulash has penned editorials for The Times of London, The New
York Times, and The Washington Post. "I've heard about nerdy being hip, but I've never known that just plain boring can be hip," Stephen Colbert noted of the deal with the not-known-for-their-non-boringness State Farm, which funded the assuredly not boring "This Too Shall Pass" video. "This is a new level of hipness!" Colbert concluded.
As befitting any band that recently parted ways with a venerable multinational corporation with their master tapes intact, OK Go also recently launched their own imprint, Paracadute. Not surprisingly, there's a new version of Blue Colour loaded with the expected demos, covers, live jams, and 12-track remix set, but also access to an online database where the band will continue to expand the album, still a breathing, growing entity.
Recorded with longtime Flaming Lips collaborator Dave Fridmann and named for a gorgeously quacky 19th century text, Of the Blue Colour of the Sky is not to be forgotten. Entertainment Weekly praised it as a "sing-along for hipsters who remember how to party unironically" and The Onion's AV Club called it "mature, compelling, and totally unexpected." MTV's Newsroom went as far as calling it the "best album of the year (so far)."
Nothing but blue ahead.
OK Go Official Website | OK Go Facebook
Official: http://www.lollapalooza.com/
Facebook: https://www.facebook.com/lollapalooza/
Twitter: https://twitter.com/lollapalooza


text:
Lisa L Anderson, MD
- Position
- ASSISTANT PROFESSOR | Obstetrics, Gynecology and Reproductive Science
- Specialty
- Gynecologic Oncology
- Languages
- English
- Spanish
- Hospital Affiliations
- The Mount Sinai Hospital
- Mount Sinai Morningside and Mount Sinai West
- Phone
- Gynecologic Oncology Associates 212-523-7752 212-523-7752
Gynecologic Oncology
Obstetrics & Gynecology
MD, Universita Di Bolongna
Internship, Surgery
Jersey City Medical Center
Residency, OB/GYN
Montefiore Medical Center /Albert Einstein College of Medicine
Fellowship, Gynecology Oncology
Brigham and Women's Hospital, Harvard Medical School
English, Spanish
National Faculty Award, American College of Obstetricians and Gynecologists
St. Luke's-Roosevelt Hospital Center
for resident education at Mount Sinai St. Luke's and Mount Sinai West
National Faculty Award, American College of Obstetricians and Gynecologists
St. Luke's-Roosevelt Hospital Center
for resident education at Mount Sinai St. Luke's and Mount Sinai West
Physicians and scientists on the faculty of the Icahn School of Medicine at Mount Sinai often interact with pharmaceutical, device and biotechnology companies to improve patient care, develop new therapies and achieve scientific breakthroughs. In order to promote an ethical and transparent environment for conducting research, providing clinical care and teaching, Mount Sinai requires that salaried faculty inform the School of their relationships with such companies.
Dr. Anderson has not yet completed reporting of Industry relationships.
Mount Sinai's faculty policies relating to faculty collaboration with industry are posted on our website. Patients may wish to ask their physician about the activities they perform for companies.
Physicians who provide services at hospitals and facilities in the Mount Sinai Health System might not participate in the same health plans as those Mount Sinai hospitals and facilities (even if the physicians are employed or contracted by those hospitals or facilities).
Information regarding insurance participation and billing by this physician may be found on this page, and can also be obtained by contacting this provider directly. Because physicians insurance participation can change, the insurance information on this page may not always be up-to-date. Please contact this physician directly to obtain the most up-to-date insurance information.
Insurance and health plan networks that the various Mount Sinai Health System hospitals and facilities participate in can be found on the Mount Sinai Health System website.


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We are excited to offer this great opportunity to acquire an unused 2019 Cup. This is an absolutely brand new car. It is ready for your shop to initialize and set up for your next track event. It comes with the factory notebook, jack stands, wheel rings, pump-out hose and air-jack wand. On the ground and ready to go in Springfield, IL. Shipping can be arranged and we will trade for any street car or Porsche race cars. Please contact Geoff Isringhausen direct by voice/text at 217-725-8000 or email@example.com
Used 2019 Porsche911 GT3 Cup
- Stock: 198289
- Exterior Color
- White
- Interior Color
- White
- Transmission
- Automatic
- Engine
- 6
Porsche 911
Dealer Notes
New Arrivals
2015 Porsche 911 Turbo S Cabri…
- $125,900
Quick Specs
- Cabriolet Turbo S
- Silver Exterior
- 3.8L 6 Engine


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Dog Is Good
Never Camp Alone T-Shirt
Regular price $25.00
Camping's better when you've got your best friend along for the trip one who might even help with any digging! 50% cotton, 50% polyester. Preshrunk, jersey knit. Standard unisex sizing. Boxier cut and roomy. Machine wash cold, inside out, with like colors only. Non-chlorinated/color-safe bleach when needed. Tumble dry low heat. Do not iron or dry clean.


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Freephone: +44 208 772 6446
We are delighted to be the Approved Provider for Music...
Does your school have a talented band, choir or orchestra?
A group of 8-11 year olds from an international school in London have had a wonderful...Read more
A choir from New South Wales have had an incredible 13-day multi-destination tour to Europe.
Do you fancy doing some skiing on your next school music tour?
Emma Kent Director of Music at West Buckland School in the UK took her choir,...
Planning and leading a music tour can be a full-time job. Our aim is take...
Ever thought about performing in the Ghentfest in Flanders? It's truly a one-off experience.Read more
Like to hear first hand what it's like to lead a school music tour? Our...
"We had yet another superb tour with great concert venues, excellent hotel and a fabulous...
With the summer holidays getting closer and exams over, now's the perfect time to start...Read more
"A very well-organised tour, with excellent concert venues."
Andrew, Director of Music, Northamptonshire
"Absolutely amazing time had by all, great location, activities and concerts. Thanks to all for organising the trip."
Andy, Party Leader, Dorset
"I feel like I owe Hannah a great deal for bending over backwards to accommodate our small group. Every message and concern was dealt with quickly, cheerfully, and efficiently."
George, Head of Music, Portsmouth
"Award three A stars to Club Europe for achievement, ambitious tour programme and all round great fun. [The location] was outstanding. I would stay there myself for a holiday."
Bruce, Director of Music, Liverpool
"All ideas and plans were listened to and acted upon. Overall a wonderful memory-packed tour in one of the most beautifully scenic places on this planet."
Andy, Head of Music, Buckinghamshire
"We had a FANTASTIC tour. It was our first music tour and I can honestly say that we all had an amazing time."
Christine, Head of Music, Nottingham
"The Tour Manager worked with us. The transfers were punctual and comfortable and the excursions lived up to (and surpassed) expectations."
Vaughan, Headmaster, Wiltshire
"A well planned and organised tour with many enjoyable and worthwhile music experiences for all participants. We've had overwhelmingly positive responses on this tour from students, staff and parents. Thanks...
Dr Crocker, Party Leader, New South Wales, Australia
"A first rate musical experience and a fun and interesting tour for both staff and students."
Chris, Head of Music, Wiltshire


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1st round struggles for Spieth, Rory and JT at the Players Championship
It's a very frustrating scene when you see Rory McIlroy, Justin Thomas and Jordan Spieth all struggle in a golf event like the Players Championship. Fans at the TPC Sawgrass saw all 3 of theses elite golfers had their difficulties on the course, displaying poor performances during the opening round. It would be expected that someone would struggle since TPC Sawgrass has been one of the most difficult courses to play according to some golf professionals.
For more details on the 1st round of the Players Championship, just click here.
Source: GOLF.com; RealFeelGolfMats


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My small team and I have created a decent sized web application (~50k lines), with a fully featured API, all in Perl. As us perl hackers know.. it is easy to get sloppy. We had to port over a lot of legacy code.. thus perl whale guts code ensued.
Long story short, we were under a fairly tight time constraint which now has been pushed back, so we have some time to go back in and standardize code.
We quickly found out how nonstandard our code was as our contractor was developing an iOS app where we have account numbers of length 10 some places, 12 in others with prepended data, etc.
As I'm going through fixing date formats and data formatting, I'm noticing a ton of really non descriptive variable and hash key naming which came from legacy code - not nice down the road maintaining it.
Basically, my question is - given the scenario above or your own experience, how far do you go when cleaning up and standardizing? Is it worth going in and replacing hash key names with longer camel cased ones, and variable names, the way data is handled in results - etc.
I know lot more pain can come from breaking working code, and it may not be worth it.. but how do you know how far to go? Get it over with now and then it pays off later, or just live with a bit of "code debt"?