Abstract:

Construction of hydropower projects will produce irreversible major disturbance on regional environment.Ecological environmental monitoring and warning as important parts of the largescale hydropower project construction,provide detailed data support for analysis and research of the regional environmental problems of engineering project,and are essential to the regional ecological environment restoration.This paper,taking Xiangjiaba hydropower project as a case,studied the environment disturbance characteristics of hydropower project construction area,and constructed environment monitoring system of engineering construction area through combining various environment factors producing disturbances.The monitoring data were analyzed and valuated by adopting the environmental factors comprehensive evaluation method.The overall status of regional environmental change rule and spatial distribution were summarized in accordance with the process of the status and changes of various environmental factors.Some conclusions are drawn as follows.Since the largescale start of the project in 2007,the ecological vulnerability greatly increased,and peaked in 2008.The environment began to improve since 2009,and maintained the situation of better than 2007 and 2008.Highly vulnerable area was mainly located in the main construction area.The region was poor vegetation coverage,and the quality of the environment affected by the project was also lower than other regions.Extremely vulnerable area was the area connected the main project and YYTH production area,not only affected by the construction projects,but also by the industrial pollution of YYTH.The moderately vulnerable area was residential area of Shuifu and the engineering subzone of the project (living area and materials processing area).This area was frequent area of human activity,affected by serious human disturbance.Low vulnerable area was process engineering area of less engineering quantities.The areas of the largest disturbance,local industrial area and transportation hub were the most environmentally vulnerable areas.Hydropower project construction,industrial and traffic were the main environmental effect perturbation factors of the construction area.Usually,there are a lot of environmental monitoring factors of a project.Despite the adoption of national standard,there is still a grading qualitative difference,and it is not conducive to mutual comparison.In addition,there are multiple monitoring results over a period of time and multiple monitoring sites in the same time.As a result,there are difficulties in evaluating the quality of the environment of the period and in comparing with other areas.Moreover,commenting on the environmental conditions needs evaluators with much relevant experience,which makes a lot of subjective uncertainty.These bring several difficulties in contrasting monitoring results of different periods and projects