黄土高原生态功能区土壤保持功能及其价值

为深入了解土壤保持重要生态功能区土壤保持服务功能,该研究在RS、GIS技术的支持下,综合应用修正后的通用土壤流失方程、市场价值法、机会成本法和替代工程法,评估了陇东黄土高原丘陵沟壑重要生态功能区生态系统的土壤保持功能及其经济价值。结果显示,从1986到2006年陇东黄土高原丘陵沟壑重要生态功能区的土壤侵蚀量逐步增强,土壤保持量和土壤保持功能总价值明显降低;1986、1996、2006年土壤保持量分别为38956×104、37834×104、34359×104t,土壤保持功能总经济价值分别为230.26×108、223.63×108、203.09×108元。在土壤保持功能总价值中保持钾素的经济价值最高,占总价值的96.41%,保持土壤有机质的经济价值最低,仅占1.52%。该区土壤保持功能空间差异性明显,东部地区的土壤保持能力在15000t/km2·a以上的区域面积较多,北部和西南部地区在1000t/km2·a及以下的区域面积较多。研究结果将为该区生态系统土壤保持功能的保护与管理提供一定的理论支撑。

Evaluation of soil conservation function and its values in major eco-function areas of Loess Plateau in eastern Gansu province

Under the support of RS and GIS technology,with integrated application of the revised universal equation on soil loss,market value approach,opportunity method and alternative engineering strategy,the soil conservation function of the ecosystem of major hilly-gully eco-function areas in Losses Plateau of eastern Gansu province and its economic value were assessed in this study.The results show that from the year 1986 to 2006,the amount of soil erosion major hilly-gully eco-function areas in Losses Plateau of eastern Gansu province has gradually increased,while the amount of soil conservation and the total value of its function have obviously decreased.The amount of soil conservation were 38956×10 4 、37834×10 4 、34359×10 4 t in the year 1986,1996 and 2006 respectively,with total economic value of soil conservation as 230.26×10 8 、223.63×10 8 、203.09×10 8 Yuan.Among the total value of soil conservation,the soil conserves potassium got the highest economic value,accounting for 96.41% of the total,while the soil conserving organic matter had the lowest economic value,only accounting for 1.52%.There was a significant spatial difference on soil conservation function in this area.In the east,most regions’ soil-conservation function is more than 15000 t/(km 2 ·a),while in the north and southwest,the predominant parameter was under 1 000 t/(km 2 ·a).The results can be used for the area ecosystem conservation and management.