土地空间多功能利用：理论框架及实证研究

Land Use Functions:Conceptual Framework and Application for China

土地利用功能(LUFs)指不同的土地利用方式所提供的产品和服务。土地多功能利用指一个区域土地利用功能及其环境、经济和社会功能的状态和表现,是评价土地利用变化对其功能可持续性影响的重要理论和方法体系,相关研究对我国土地利用研究具有重要的理论价值和现实意义。本文界定了土地多功能利用的理论,构建了分析框架,并以我国1985年至2005年土地利用为例,实证了该框架应用的步骤:以可持续性三维度为基础,选取与土地利用密切相关的指标体系;界定多功能性,建立指标与多功能性之间多维度关联矩阵;对指标进行标准化处理,评估土地功能。实证研究揭示:中国土地利用总功能在1985年～2005年实现了倍增发展,确定的10项功能中,就业支持功能下降了1/3强;生态过程维持功能被超强度利用;降低污染排放功能发生恶性退化;其他功能均有不同程度提高,其中健康保障与人工化土地生产功能提高幅度最为显著,均实现3倍增长。期间总功能的实现率提高了1倍,达到0.37,其中资源维持与供给功能实现率已经达到0.83,但各环境功能实现率尚处于负值状态。建议在土地利用政策制定和实施过程中,应当充分考虑其功能的全面提升。

Land Use Functions （LUFs） are the goods and services provided by the different land uses that summarize the most relevant economic, environmental and societal issues of a region. The LUFs framework integrates the changes observed in a large set of indicators into LUFs, which is used to assess the impact of policies on land sustainability at various levels of spatial aggregation. In China, significant changes in land use over the past decades calls for a need of assessment of sustainability of such changes, the relevant study is of both theoretical and practical importance for sustainable development. This paper establishes a conceptual framework for assessing LUFs, and demonstrates its application by tracing land use changes and associated functional changes in China from 1985 to 2005. The major steps are identification of environmental, economic and social indicators related to land use change and impact; investigation of the nature of the relationship between indicators and LUFs through establishing matrix of indicators charactering each LUF; identification of the importance （weighting） of each key impact indicator for the sustainability of the regions ; assessment of sustainability limits for the regions and normalization of indicator values; and integrated assessment of the effect of a policy scenario on the sustainability of the land use in a region. Following those steps, altogether 10 LUFs is identified for China, and the results indicate that the overall LUFs of China had been increased over the past 20 years extending from 1985 to 2005. Specifically, among the 10 LUFs, provision of employment opportunity decreased more than 30 percent, maintenance of ecosystem processes was over-explored, and reduction of pollutant emission weakened. However, rest of the LUFs was enhanced, out of which human health and artificial land productivity functions increased by 3 folds. Beside, achieving rate of the total LUFs to the top value increased to 0.37, doubled the value in 1985, of which resource maintenance and provision function increased to 0.83, implying that there is only 0.17 gaps to reach its full value of 1.00. However, environmental functions are still at a lower level and need to be improved. It is concluded by saying that land use policy would have to consider its impact on LUFs of land resources for its sustainable use.