漓江流域生态系统服务价值最大化的土地利用结构优化

土地利用结构优化是促进生态系统可持续发展的重中之重，而生态管理的最终目标是优化生态系统服务，使生态系统提供的服务达到最大化。选择典型生态脆弱区漓江流域为研究区，将整个生态系统服务价值的最大化作为研究目标，首先结合野外实验和五期Landsat高分遥感影像获取基础数据，对研究区1998-2018年各项生态系统服务价值进行估算，然后结合灰色线性模型对2018-2028年价值进行预测，借助Lingo软件提出生态效益最大化的土地结构优化方案，进而对优化前后研究区生态系统服务价值进行比较与分析。结果表明：（1）近20年间研究区主要土地利用类型一直以林地与耕地为主，所占比例保持在整个流域的95%。水域与耕地面积逐年减少，林地、建设用地及未利用地面积持续增加。此外，未利用地面积发生的变化最为显著，增加了近30倍，主要由林地与耕地转变而来。（2）研究区生态系统服务价值总体约减少了19.55×10⁶元，呈现先上升后下降趋势，并将长期处于下降趋势，至2028年时流域生态系统服务价值将减少至8067.43×10⁶元。在流域整体生态系统中，林地价值最高，在历年约占流域总价值的86%，其次是水域及耕地，分别占比8%、6%。（3）对研究区进行优化后，漓江流域总生态系统服务价值增长了2%，其中主要来源于林地与水域面积的增加，提高了生态系统调节服务的供给能力，耕地、建设用地面积略微增加，未利用地面积显著减少，基本与2008年水平持平。本研究通过优化喀斯特地区关键生态系统服务价值，为该区域生态管理提供科学支撑。

Land-use structure optimization for the Lijiang River basin ecosystem service value maximization

The land utilization structure optimization will promote the sustainable development of ecosystems, which is the top priority. The ultimate goal of ecological management is to optimize the ecosystem services to maximize the services provided by the ecosystem. The paper select the typical ecologically fragile Lijiang River basin as the study area, and the maximization of the value of the whole ecosystem services as the research target. First, combined with field experiments and five phases of Landsat high-resolution remote sensing images to obtain the basic data, estimated each item from 1998 to 2018 for the value of ecosystem services research area. Then combined with the gray linear model for predicting the value in 2018-2028. Final,with the help of Lingo software so as to put forward the optimization scheme of land structure to maximize ecological benefits, and then further to making comparison and analysis for the ecosystem value in research area where were optimized before and after. The results showed that (1) Nearly 20 years, in study area the principal land-use types are forestland and cultivated land, which accounts for 98% of whole drainage basin. The water area and cultivated land area decreased year by year, but the forestland and construction land as well as unused land area continue to increase. In addition, unused land area had changed obviously, which even increased around 30 times and mainly converted from forest land and cultivated land. (2) During studying, the value of ecosystem service had decreased around 19.55×10⁶ RMB, which showed the trend of down after up and will keep such trend in long term. Till 2028, the drainage basin ecosystem services values will be reduced to 8067.43×10⁶ RMB. So, the forest land value is the highest among the overall ecosystem of the drainage basin, which occupies around the 86% of basin total value in past years, followed by the water area and cultivated land area, which account for 8% and 6% separately. (3) After optimizing the study area, the total ecosystem services values in the Lijiang River basin has increased 2%, which mainly because the forest land and water area increased and improved the supply capacity for the ecosystem regulating services. Meanwhile, the arable land and construction land increased slightly, and the area of the unused land decreased significantly, which keeps the same level in 2008. This study provided the scientific support for ecological management in karst areas by optimizing the key ecosystem services values.