Environmental application of aerial reconnaissance to search for open dumps
Three approaches to using aerial photography are evaluated for searching for open dumps in the state of Indiana. Photography with hand-held cameras from a small airplane proved more effective and flexible than either photo-interpretation of existing air photos or subcontracting to a federal agency for new aerial photography. The rationale for our choice of aerial reconnaissance, other uses of low-level aerial surveillance, the utility of small-format camera aerial photography for environmental analysis, and methods used for locating open dumps are discussed.
VISUAL INTERPRETATION OF SATELLITE AND AERIAL IMAGES TO IDENTIFY AND STUDY THE EVOLUTION OF INADEQUATE URBAN WASTE DISPOSAL SITES
One of the main problems Brazil faces in solid waste management is the existence of dumpsites that must be closed. For the shutdown process, an environmental assessment should be performed, which requires knowledge of the history of these sites. This study is often hampered by the lack of past records on the waste disposal activities in these places, especially when they are very old. In this context, the analysis of multitemporal remote sensing images and aerial photographs is an interesting tool for the identification and study of the development of inadequate waste disposal sites. In the present study, these techniques were used to assess former dumps in four municipalities in the state of Sao Paulo, Brazil. The analysis comprised satellite images and aerial photographs between 1960 and 2010. They enabled the obtainment of information on the progress of activities in the dumps and their surroundings, on how the waste disposal occurred, and on the end of operations and the revegetation process. With geographic information system (GIS) support, information from different data sources was crossed with previous databases, thus allowing the obtainment of greater data structure for a better interpretation of the available information. Thus, the interpretation of multitemporal remote sensing images and aerial photographs allowed a better interpretation of the posterior environmental assessment data through the knowledge of the context in which these were inserted.
Aging live Antarctic fur seals and southern elephant seals
This study describes a method for extracting post-canine or incisor teeth from live antarctic fur seals (Arctocephalus gazella) and southern elephant seals (Mirounga leonina) respectively and their use to determine age in a field situation. Dental elevators were used to loosen the teeth from the alveolus and periodental ligament. Most teeth were removed within l-2 min and a total of 214 and 81 teeth were collected by this method from antarctic fur seals and southern elephant seals respectively. No seal recaptured at intervals up to a year after a tooth was extracted showed signs of infection or distress related to removal of the tooth. Teeth were thin-sectioned for the purpose of aging. In both species cementum growth layer groups were a more satisfactory indicator of age than dentinal growth layer groups. Estimates of age from cementum growth layers were confirmed for Antarctic fur seals using seals which had been tagged as pups up to 16 yr before sampling.