Contributions for the use of qualitative indicators: an analysis of Itaipu Power Plant’s Sustainability Program

An integrated approach based on multiple indicators and individual and combinational evaluation methods is proposed to evaluate water scarcity. Four evaluation methods are employed, and their results are joined through three combination methods in order to obtain a consistent evaluation. This iterative-correction approach has been applied to Yunnan Province in China for water scarcity evaluation. The results demonstrate the capability of the iterative-correction framework to provide insightful analyses of water scarcity. Diqing Tibetan Autonomous Prefecture (Diqing) and Nujiang Li Autonomous Prefecture (Nujiang) ranked 1st and 2nd, indicating the best situation for water scarcity evaluation, while Yuxi and Zhaotong ranked 15th and 16th, indicating the worst situation. Two types of major water scarcities were observed in Yunnan Province. One was a typical representative of lack of water quality in the central part of Yunnan, and the other was a typical engineering type in the western part of Yunnan. The water scarcity has been found to arise from non-judicious water use, rapid urbanization and lack of protective measures for water resources. Therefore, it is necessary to conduct more water conservancy projects in future to alleviate the water scarcity issue.     

Management of invasive populations of the freshwater crayfish <Emphasis Type="Italic">Procambarus clarkii</Emphasis> (Decapoda,Cambaridae): test of a population-control method and proposal of a standard monitoring approach

Invasive species are one of the main threats to biodiversity. When an alien species is introduced into a new environment, fast identification and definition of management strategies may avoid or minimize impacts. When an invasive species is already established, the most adopted approaches are population control and monitoring. In order to perform such strategies, assessment of characteristics of the invasive population is imperative. This study tested a new method of population size estimation and monitoring in an invasive population of crayfish Procambarus clarkii in a conservation area in the Atlantic Rain Forest (Southeastern Brazil). The population dynamics was studied for 1 year to examine the efficacy of the selected method and to evaluate if the population is stable. Later, the effect of periodical removal of animals on the population size was tested. The method of population estimation used in this study proved to be very effective. We recommend using it to monitor invasive populations of P. clarkii. The population size varied discretely over the year with variable but low growth rate, indicating that the population is already established which introduce a notable threat to native species. The continuous removal of specimens proved to be inefficient since the growth rate was higher after the removal. One intensive removal event might be more effective than a continuous moderate removal as the one applied in this study.