The monthly, seasonal, and annual precipitation trends in the Yangtze river catchment have been detected through analysis of 51 meteorological stations' data between 1950-2002 provided by National Meteorological A...The monthly, seasonal, and annual precipitation trends in the Yangtze river catchment have been detected through analysis of 51 meteorological stations' data between 1950-2002 provided by National Meteorological Administration. Results reveal that: 1) Summer precipitation in the Yangtze river catchment shows significant increasing tendency. The Poyanghu lake basin, Dongtinghu lake basin and Taihu lake basin in the middle and lower reaches are the places showing significant positive trends. Summer precipitation in the middle and lower reaches experienced an abrupt change in the year 1992; 2) The monthly precipitation in months just adjoining to summer shows decreasing tendency in the Yangtze river catchment. The upper and middle reaches in Jialingjiang river basin and Hanshui river basin are the places showing significant negative trends; 3) Extreme precipitation events show an increasing tendency in most places, especially in the middle and lower reaches of the Yangtze river catchment.展开更多
Deforestation caused bythe felling of trees for firewood is a major cause of environmental degradation in some villages in Luchun Counth,Yunnan Province.This is of particular concem in the headwaters ofmajor rivers su...Deforestation caused bythe felling of trees for firewood is a major cause of environmental degradation in some villages in Luchun Counth,Yunnan Province.This is of particular concem in the headwaters ofmajor rivers such as the Black River where increased runoff,erosion,and sediment yield impact on the millions of persons living downstream.While the links between forest clearance,the ability ofthe land to sustain production,and the sustainability of communities are understood,the pressures of having to survive today often outweigh consideration of the consequences for tomorrow.The real challenge for these communities is that they recognise their situation and negotiate a practical solution rather than walt the intervention and support.It is essential therefore that the changes which have taken place are documented and their future impact illustrated.This information must then be portrayed in a manner that makes it accessible and comprehensible to all,even to those who are illiterate.For this reason the use of graphics offers considerable merit over textual and numerical analyses.This paper explores the use of MIGIS (an acronym for community based planning which integrates the techniques of PLA and GIS) to facilitate a negotiated,bottorn-up approach to afforestation with the Hani farmers of Luchun County,Yunnan in southwest China.展开更多
文摘The monthly, seasonal, and annual precipitation trends in the Yangtze river catchment have been detected through analysis of 51 meteorological stations' data between 1950-2002 provided by National Meteorological Administration. Results reveal that: 1) Summer precipitation in the Yangtze river catchment shows significant increasing tendency. The Poyanghu lake basin, Dongtinghu lake basin and Taihu lake basin in the middle and lower reaches are the places showing significant positive trends. Summer precipitation in the middle and lower reaches experienced an abrupt change in the year 1992; 2) The monthly precipitation in months just adjoining to summer shows decreasing tendency in the Yangtze river catchment. The upper and middle reaches in Jialingjiang river basin and Hanshui river basin are the places showing significant negative trends; 3) Extreme precipitation events show an increasing tendency in most places, especially in the middle and lower reaches of the Yangtze river catchment.
文摘Deforestation caused bythe felling of trees for firewood is a major cause of environmental degradation in some villages in Luchun Counth,Yunnan Province.This is of particular concem in the headwaters ofmajor rivers such as the Black River where increased runoff,erosion,and sediment yield impact on the millions of persons living downstream.While the links between forest clearance,the ability ofthe land to sustain production,and the sustainability of communities are understood,the pressures of having to survive today often outweigh consideration of the consequences for tomorrow.The real challenge for these communities is that they recognise their situation and negotiate a practical solution rather than walt the intervention and support.It is essential therefore that the changes which have taken place are documented and their future impact illustrated.This information must then be portrayed in a manner that makes it accessible and comprehensible to all,even to those who are illiterate.For this reason the use of graphics offers considerable merit over textual and numerical analyses.This paper explores the use of MIGIS (an acronym for community based planning which integrates the techniques of PLA and GIS) to facilitate a negotiated,bottorn-up approach to afforestation with the Hani farmers of Luchun County,Yunnan in southwest China.