人类活动干扰下陇中黄土高原生态系统服务功能相互关系研究

Soi1 erosion is the most serious problem in the Loess Plateau. The adverse human impacts on ecosystems have degraded the already-vulnerable ecological conditions, which are in turn diminishing the ecosystem services and directly threatening the economic sustainability. However, there exists shortage of research about the interactive relationships between provisioning and conserving soil services under huaman activities. Habitat, ecosystem structure and ecosystem processes are the basis of ecosystem services. Therefore, according to the basis affected by human activities, this project takes representative arae in Longzhong Loess Plateau (Zuli River basin) as a study area. Three scientific themes will be focused on: ① experiment plans and measurements of runoff and sand which are relative to formation mechanism of soil conservation service in different stage of land use and cover; ② simulation of the temporal and spatial changes of ecosystem service patterns about provisioning and conserving soil services; ③interactive relationships between provisioning and conserving soil services and assassing the impact of human activities on the relationships. The objectives are to understand the effect of human activities on the ecosystem services, to define the areas where trade-offs and synergies between provisioning and conserving soil services will happen, to predict the change trend of ecosystem services under different scenes of management practices. We hope that the research results can be used to manage ecosystems in the study area for sustaining social and economic development. The integrated valuation model coupling ecosystem services and hydrological and growth processes will be innovation of the project, developing tradeoff index between provisioning and conserving soil services will be another innovation. Themes in the project need many principles of different research field to study and have explicit application prospect. Thus, the project is characterized by the multidisciplinary research and have a feature expressing close relationship between theory and practice.

陇中黄土高原在高强度的人为活动作用下，水土流失问题已经影响到人类的生存环境。分析人类活动下生态系统供给服务功能与土壤保持服务功能相互作用的时空演变规律，为维持生态系统服务功能稳定、制定区域可持续发展对策具有重要的意义，本项目通过实验研究与数值模拟相结合的方法，以遥感、地理信息系统为技术支撑，主要开展：①不同生态系统下的径流泥沙观测试验研究；②生态系统供给与土壤保持服务功能空间分布模拟；③生态系统供给-土壤保持服务功能相互关系分析；④不同人类活动情景下供给服务与土壤保持服务相互关系预测。根本的目在于深刻理解人类活动对生态系统的供给功能与水土保持功能影响机制，界定关键生态系统服务之间的竞争和协同增强作用区域，权衡人类活动的效益和影响，为科学地管理生态系统和实现人类社会的可持续发展提供科学依据。项目的创新点是生态水文过程与关键生态系统服务功能形成机制耦合，充分反映出多学科交叉、区域特色。

人为活动是黄土高原生态系统变化的快速驱动力，在短时间内经历了从荒坡开垦到退耕还林（草），再到封山育林（草）及林地草场管理等政策的演变，使得土壤保持服务功能与供给功能处于竞争中。以经济优先、环境良好、社会经济可持续发展为方向，本项目试图回答两大问题：①生态系统服务供给与土壤保持功能的竞争与协同作用可能在哪里发生？②人类将影响生态系统服务功能的活动规模与强度控制到什么样的水平，才能减弱供给与土壤保持服务功能之间的竞争作用，同时加强它们的协同增强作用？.为此，研究内容包括：①不同生态系统下的径流泥沙观测试验研究；②祖厉河流域生态系统供给与土壤保持服务功能空间分布模拟；③祖厉河流域生态系统供给与土壤保持服务功能相互关系分析；④不同人类活动情景下生态系统供给服务与土壤保持服务相互关系预测。.通过项目执行，获得重要结果如下：①称钩河流域土壤侵蚀强度分级，土壤保持和碳储存功能分级。将土壤保持和碳储存服务进行叠置分析，得到称钩河流域综合生态系统服务划分；②获得研究区水土保持量空间分布和碳储量空间分布；③识别出研究区土壤保持、碳储存和作物生产服务功能冷热点区域。同时获得的重要数据：①祖厉河流域关键环境因子数据并产生关键环境因子的空间分布；②利用RTK对研究区坝区进行高精度的地形测量，获得0.6m、2m和5m三种分辨率的DEM地形图；③长序列研究区土地利用数据；④大量的观测数据，包括优势物种沙棘，柠条，油松叶片水势、光合数据、比叶面积和叶面积指数，不同物种的生境土壤水分，枯落物的持水量，控制坝区泥沙淤积量；④研究区的高分一号PMS1遥感影像数据及在此基础上解译的土地利用类型。.研究结果和重要数据为深刻理解人类活动下的生态系统的供给功能与水土保持功能的相互关系奠定了基础，为制定减弱生态系统服务之间的竞争、加强协同增强作用的管理策略及科学地管理生态系统和实现人类社会的可持续发展提供科学依据。