渭干河-库车河三角洲绿洲50 a来农业开发及所引发的生态问题探析

从渭干河-库车河三角洲绿洲50a来农业开发与生态建设的过程看，人工绿洲耕作农业的生产力水平有较显著的提高，人工绿洲生态也得到了改善。主要表现是单位面积生产力水平提高，农田防护林体系初步建立，水利工程建设得到加强，生活能源的短缺得到改进。但从流域的绿洲农业经济发展与生态环境建设仍存在一些不协调的问题。主要是农田施肥重化肥轻有机肥，土壤肥力不高；灌区中游重灌轻排，灌排不协调，盐渍化面积有所扩大；流域下游由于缺水和人为等因素使天然绿洲的稳定性受到威胁，天然林的绿色屏障作用大为削弱等。对此必须引起足够重视，逐步加以协调，才能实现绿洲农业经济的可持续发展。

Agricultural Exploitation of the Delta Oasis of Weigan-Kuqa River during Recent 5 Decades and Analyses of its Ecological Problems

Viewed from the history on agricultural exploitation and ecological construction of the delta oasis of Weigan-uqe River, the productivity of cultivation agriculture on artificial oasis has been remarkably heightened and its ecological environment has also been improved a lot. For example, the productivity per unit area has increased, the agricultural forest protection system has been established gradually, the hydraulic engineering has been consolidated, and the shortage of living energy source has been solved. But there are still some unharmonious problems between the economical development of oasis agriculture and the ecological environment construction. The main problems are as below: using more chemical fertilizer than organic fertilizer, which resulted in poor soil fertility; paying much attention to irrigation than drainage in middle reaches, consequently the area of saltings became larger; water shortage and anthropogenic factors in lower reaches threatened the stability of oasis, which has largely weakened the green shelter function of natural forest system. Only by coordinating, can we realize the sustainable development of oasis agricultural economy.