首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   2篇
  免费   0篇
环保管理   1篇
评价与监测   1篇
  2007年   2篇
排序方式: 共有2条查询结果,搜索用时 15 毫秒
1
1.
During recent decades, Lake Koronia has undergone severe degradation as a result of human activities around the lake and throughout the basin. Surface and groundwater abstraction and pollution from agricultural, industrial, and municipal sources are the major sources of degradation. Planning a restoration project was hampered by lack of sufficient data, with gaps evident in both spatial and temporal dimensions. This study emphasized various remote sensing and geographic information system techniques, such as digital image processing and geographic overlay, to fill gaps using satellite imagery and other spatial environmental, hydrological, and hydrogeological data in the process of planning the restoration of Lake Koronia, following Ramsar guidelines. Current and historical remote sensing data were used to assess the current status and level of degradation, set constraints and define the ideotype for the restoration, and, finally, define and select the best restoration scenario.  相似文献   
2.
Survey techniques for larval salamanders vary in their effectiveness and efficiencies. In this study, the leaf litterbag sampling technique was employed to gather data on larval salamander populations in perennial streams of southern Georgia. Salamanders were collected monthly for 12 months to analyze capture counts and population size-class structure. Simultaneous dipnet sweep data were used to examine potential count data biases of the leaf litterbag sampling technique. In both leaf litterbag and dipnet sweep surveys, adult and larval Southern Two-lined Salamanders (Eurycea cirrigera) and larval Southern Red Salamanders (Pseudotriton ruber) were sampled. In leaf litterbags, larval E. cirrigera were captured most frequently, followed by adult E. cirrigera and larval P. ruber, respectively. However, the efficiency of collecting adult E. cirrigera and larval P. ruber could not be determined because of small sample sizes. Larval E. cirrigera counts detected from leaf litterbags were frequently lower than those associated with dipnet sweeps, suggesting that the former may underestimate larval salamander counts. Leaf litterbags successfully detected all E. cirrigera size-classes (i.e., first-year, second-year, and adult), further indicating that larvae in Georgia spend 2 years in the aquatic phase. Leaf litterbags are an effective method of sampling larval salamanders when used to assess species assemblage and age-class distribution.  相似文献   
1
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号