西北内陆区农业生态系统资产负债研究——以甘肃省凉州区为例

本文以甘肃省凉州区为例,分析了其绿洲农业区1949～2005年生态系统可持续发展能力的资产负债动态变化,探究西北内陆区绿洲农业生态系统可持续发展能力,预测其可持续发展程度及未来趋势.结果表明:甘肃省凉州区农业生态系统的资产在1949～1970年为急速下降阶段,由14.14下降至4.93,下降65.13%;1970年以后为缓慢增长阶段,至2005年增长到33.33.负债自1949年以来,一直呈负增长趋势,由-0.91增长至-56.67,负增长了61.27倍.净资产也呈明显的先降后升趋势,1949～1970年,以环境资产占优势,表现为资产盈余,且呈递减趋势,至20世纪70年代初期,净资产接近于0;1970年以后,以负债量占优势,表现为资产赤字,且呈递增趋势,尤其在20世纪80年代后期以后,几乎呈直线上升,但自2000年以后,负债量有所减少.2005年凉州区农业生态系统可持续发展能力资产负债分布表的结果表明,生存、发展、环境、社会和智力5大支持系统的共30项源指标中有10项列入"资产"栏目,17项列入"负债"栏目,凉州区净资产为-23.34.本研究结果表明,凉州区农业生态系统处于不可持续状态,但其生态环境的自然资产库存量已经开始增加,人类再次向可持续发展方向迈进.

Analysis of assets and debts of agro-ecosystems in northwest China——A case study of the oasis agro-ecosystem of Liangzhou District,Gansu Province

The dynamics and magnitude of assets and debts of oasis agro-ecosystems in Liangzhou District, Gansu Province were analyzed for the period of 1949~2005. The analysis explored sustainable development capacity and predicted future oasis agro- ecosystem development in Northwest China. The results show a rapid decline in the environmental assets of the agro-ecosystem from 1949 to 1970, dropping on the average from 14.14 to 4.93, which is 65.13% reduction. There is also a slow increment to 33.33 from 1970 to 2005. A steady negative growth exists in environmental debt from -0.91 to -56.67, increasing 62.27 times from 1949 to 2005. Net environmental assets exhibit a decreasing/increasing trend for the period under study. Environmental assets are strategic, gradually driving weakening asset surplus from 1949 to 1970, and dropping to zero in the 1970. Since 1970, debts have become dominant in the oasis agro-ecosystem, leading to asset deficit that has gradually increased, especially in the late 1980s. However, the situation begins to improve after 2000. The asset/debt table in 2005 shows that among 30 source indexes of livelihood, development, environment, society and intelligence supporting systems of sustainable development ability, 10 are in the asset column, 17 in the debt column, with a net asset of -23.34 for Liangzhou agro-ecosystem. The study shows that economic development in Liangzhou District is far from sustainable, however, environmental asset storage of the agro-ecosystem is lately improving. This implies that economic development in the region is transforming from a non-sustainable to a sustainable mode.