Aquatic systems and water security in the Metropolitan Valley of Mexico City
In megacities water quantity and quality are threatened by complex and interrelated processes caused by population growth, land use change, unsustainable agricultural practices, deforestation, erosion, destruction of ecosystems, lack of planning, laissez-faire policies, unsustainable water management, political conflicts, and increasingly also by the impacts of climate change. In the Metropolitan Valley of Mexico City (MVMC) located in the high plateau of Mexico City and on former lakes, the dry out policies during the last 300 years have been counterproductive, causing scarcity, pollution, health and environmental problems, subsidence and water conflicts, particularly affecting social vulnerable people. Megacities require an integrated management of water and aquatic systems — integral water resource management, rainwater harvesting, maintenance and replacement of infrastructure, restoration of ecosystems and urban planning. This implies investments and a water culture including a transparent administration and peaceful negotiation of conflicts regarding concessions, access, and reuse of water allocation. Socio-political and environmental processes are complex; besides technical factors and ecosystem recovery, socio-cultural changes must transform human settlements and power structures.
Evaluating Stream Degradation in Villa De Allende, Mexico: The Effect of Rural Development on the Taxonomic Richness and Relative Abundance of Benthic Macro-Invertebrates in Mexican Headwater Streams
I examined the anthropogenic effects on the water quality of headwater streams in the western mountains of the state of Mexico. Rural development has negative effects on the ecology of local streams by diverting and pumping surface and groundwater, removing riparian forests for the construction of buildings, roads, and agricultural fields, and dumping refuse in stream channels. Local development, construction, roads, and agriculture also are sources of pollution that enter the streams during rain events. These negative ecological effects are common to many streams in the watershed of the Chilesdo dam. The combined effects of human development negatively affect the quality of surface water and groundwater aquifers.
The issue of anthropogenic effects on the water quality of headwater streams is relevant ecologically because of likely effects on flora and fauna that depend on these streams and because of the role of headwater streams in the context of the larger watershed. Effects on upstream areas directly affect people, animals, and plants downstream. This issue is relevant economically because rural communities depend on the availability of water of suitable quality for agriculture and livestock. In addition, local water quality directly affects the cost of water purification downstream at dams that feed the Cutzamala system, a major source of Mexico City’s drinking water. This issue is relevant socially because the local community depends on this water for domestic consumption. Compromising water quality and abundance could destabilize the lives of local people because poor water quality and water contamination are a public health concern. Additionally, climate change is likely to make this resource scarcer. Projections for all major scenarios used by the International Panel on Climate Change indicate elevated year-round temperatures and decreased overall precipitation in the region (IPCC 2013).
I addressed concerns over water quality by testing differences among streams with anthropogenic alterations and a stream that had few anthropogenic alterations. I sampled benthic macro-invertebrate communities as indicators of water quality within the streams. Benthic invertebrates are a useful bio-indicator for water quality and environmental disturbances in river systems because different taxonomic groups of invertebrates have different tolerances to water pollution. I measured the abundance and taxonomic richness of invertebrates that exhibit different sensitivities to water quality.
My results revealed that taxonomic richness was lower in streams that had anthropogenic alterations. My results also revealed that the abundance of “sensitive” and “somewhat sensitive species” were lower and that the abundance of “pollution-tolerant species” was higher in streams with anthropogenic alterations. The stream with few anthropogenic alterations had the highest taxonomic richness and largest number of sensitive and somewhat sensitive species. These results indicate that human activities are having negative effects on water quality.
Given my results, I suggest that restoration of degraded streams should reduce water diversion, riparian encroachment, and refuse disposal. I propose solutions to guide these restoration efforts. My data suggests that a coordinated local and regional effort is required to reduce the negative effects of human development and to restore local streams to an ecological condition that will sustain water quality and quantity to enable local communities and the local environment to thrive.
Biomonitors and Biomarkers as Indicators of Environmental Change 2 : A Handbook
1. Introduction F.M. Butterworth, et al. Section I: Automated monitoring: On-line monitoring. 2. A Brief Review of Chemical and Biological Continuous Monitoring of Rivers in Europe and Asia A. Gunatilaka, P. Diehl. 2. The Evaluation of 'Dynamic Daphnia Test' after a Decade of Use: Benefits and Constraints A. Gunatilaka, et al. 4. The 'Musselmonitor(R)' as Biological Early Warning System: The First Decade K.J.M. Kramer, E.M. Foekema. 5. Quantitative Behavior Analysis - A New Approach to the Challenges of Environmental Toxicology O.H. Spieser. 6. An Introduction to Behavioral Monitoring - Effects of Nonylphenol and Ethinyl-Estradiol on Swimming Behavior of Juvenile Carp O.H. Spieser, et al. 7. How to Use Fish Behavior Analysis to Sensitively Assess the Hazard Potentials of Environmental Chemicals D. Baganz, et al. 8. Continuous Water Monitoring: Changes of Behavior Patterns as Indicators of Pollutants M. Blubaum-Gronau, et al. Automation technologies. 9. Restoration and Classification of Water-Borne Microbial Images for Continuous Monitoring of Water Quality M. Das, F.M. Butterworth. 10. Screen-printed Disposable Biosensors for Environmental Pollution Monitoring D.C. Cowell, et al. 11. Optical Sensors and Biosensors for Environmental Monitoring P. Scully. Section II: Recombination and recombinogen detection. 12. Recombination as Indicator for Genotoxic and 'Non-genotoxic' Environmental Carcinogens. 13. Somatic Mutation and Recombination Test in Rosophila Used for Biomonitoring of Environmental Pollutants J.Guzman-Rincon. 14. A New Way to View Complex Mixtures: Measurement of Genotoxic Effects of Mixtures of a Polychlorinated Biphenyl, a Polyaromatic Hydrocarbon, and Arsenic R.M. McGowen, et al. 15. Drosophila is a Reliable Biomonitor of Water Pollution P. Ramos-Morales, et al. Section III: New approaches and applications of established systems: Sentinel systems. 16. A New Multispecies Freshwater Biomonitor for Ecologically Relevant Control of Surface Waters A. Gerhardt. 17. Cytogenetic and Cytotoxic Damage in Exfoliated Cells as Indicators of Effects in Humans M.E. Gonsebatt. p53 Mutation Load: a Molecular Linkage to Carcinogen Exposure and Cancer S.P. Hussain, C.C. Harris. 19. Plant Biomonitor in Aquatic Environments: Assessing Impairment via Plant Performance L. Lovett-Doust, J. Lovett-Doust. 20. Fish Chromosomes as Biomarkers of Genetic Damage and Proposal for the Use of Tropical Catfish Species for Short-term Screening of Genotoxic Agents M. Uribe-Alcocer, P. Diaz-Jaimes. Laboratory-based biomonitors. 21. The Tetramitus Assay R.L. Jaffe. The Use of Aquatic Invertebrate Toxicity Tests and Invertebrate Enzyme Biomarkers to Assess Toxicity in the States of Aguascalientes and Jalisco, Mexico R. Rico-Martinez, et al. 23. Biomonitoring of Pesticides by Plant Metabolism an Assay Based on the Induction of Sister-Chomatid Exchanges in Human Lymphocyte Cultures by Promutagen Activation of Vicia faba S. Gomez-Arroyo, et al. 24. Genetic Monitoring of Airborne Particles R. Villalobos-Pietrini, et al. Section IV: Abstracts. 25.