摘要
对河北坝上内蒙古乌盟后山地区解放以来农业人口、牲畜头数与沙漠化总体退化状态、退化景观在空间界线上互动关系的研究表明 ,近 5 0 a人畜压力界线的推移显示出高度的同步性 ,80年代以前向北推 ,以后停滞甚至回撤 ,只有东部持续前移。相应地沙漠化总体退化状态普遍加重 ,退化景观界线向南推进。表现在程度类型界线上 ,轻度沙漠化范围向南退缩 ,中度界线向东南推进 ,重度类型在旱作北界附近由分散分布发展为东西连绵的重度轴 ;反映在退化地貌类型上 ,农田土壤风蚀范围北推扩大 ,砾石戈壁线明显向南向西移动 ,沙质线缓慢南移。上述互动关系在深层次上揭示了人畜压力同土地生产力之间相互制约的关系 ,80年代以后人畜压力界线的回撤 ,体现了土地退化对人口超载的反馈调解作用。
In the paper, approach is made to the interaction between boundaries of degradation land and the pressure on land in spatial movements in the Houshan area of Bashang since liberation. Pressure on land for population and husbandry changes in almost the same way which grows all the area, but higher to the north, especially in the northeast part during 1950\_1996. The creeping of pressure lines displays differently,from 1950\_1980 lines in area of Houshan move north and get back since 1980,only that in Bashang pushes northeast continuously during 1950\_1996. In the response, land degradation severity aggravates through the area, light degree of desertified land decreases, moderate degree line of >20% moves towards southeast by 45 km. The types of different severity degrees that distributed separately in the 1970's link together from west to east, forming an axis of severity degree in the 1980's. In the desertified landscape, farmland experiencing wind erosion of >30% develops rapidly moves northward by 30 km, pebble line of >30% swifts south and west in large scale, but the sandy line pushes south a little and remains unchanged in the east. Getting lower in speed even withdraw in movements for pressure line reveals the regulation of population capacity by land degradation since 1980's.
出处
《中国沙漠》
CSCD
北大核心
2000年第2期154-158,共5页
Journal of Desert Research
关键词
坝上后山地区
人畜压力
沙漠化景观界线
互动
Houshan area of Bashang
population and livestock pressure
desertified landscape
interaction
