生态脆弱区的生态重建与景观规划

通过对生态脆弱区生态建设目标和内涵的分析,提出生态建设尺度性的概念,从理论上总结了景观生态建设的目标、内容和设计指导原则。并以沙地田、草、林体系,三北农田防护林网络体系,黄土高原农、草、林立体镶嵌模式为例,论述了这类景观尺度上的生态建设乃是以景观单元空间结构的调整和重新构建为基本手段,通过增加景观异质性的办法创造新的景观格局;在原有的生态平衡中引进新的负反馈环,实行多种经营、综合发展以增加系统的稳定性,取得了超过自然生态系统的生产力,并且保持了生态环境的可持续性。这是一种具有中国特色的农村景观规划思路,可与20世纪90年代以来国际上流行的持续农业发展研究相接轨。

Ecological Reconstruction and Landscape Planning of Ecological Fragile Zone

The word, ecological construction, has been widely used in China. Its implications are ambiguous and its spatial extent ranges widely from the ecological design and management of a family yard to that of ecological village, ecological town, ecological county and ecological city. Hence, it is necessary to give ecological constriction at the landscape and regional scale a name: landscape ecological consummation (LEC). This approach adds spatial elements and alters landscape pattern to strengthen inter\|ecosystem linkages, improve functioning of damaged ecosystems, and increase productivity and stability of the whole landscape. The goals of LEC are as follows: (1) guarantee ecological security, (2) increase the total productivity of ecosystem in the landscape, (3) conserve landscape diversity and construct sustainable landscape. The contents of LEC include modifying the spatial pattern of landscapes, controlling the intensity and ways of human activities, exploiting renewable natural resources by ecological principles and constructing new artificial landscapes. Some design principles of LEC are also introduced in the paper: (1) reciprocal interactions or feedbacks between landscape and their functions; (2) harmonize human control with biocybernetic symbiosis; (3) ecological unification of the socialeconomicnature complexity; (4) conserve and increase landscape diversity and spatial heterogeneity; and (5) local control modification of the whole and adjusting measures to local conditions. Many successful models of landscape ecological construction have been created by Chinese people in the long history. Three examples highlight a variety of key approaches and solutions: fieldgrasswood system on unstable sand dunes, shelter belt network in a crop field area of the \!Three North\" regions, and fieldgrasswood mosaic system in Loess Plateau. Each was explained in details. These indicate that ecological conditions can be improved along with increased economic production. In addition, according to the situation of China and current demand, the contents of sustainable agriculture and rural development were generalized: switch mechanism of agriculture and rural area sustainable development, sustainable decision\|making support system of regional agriculture, the technique intimation of sustainable agriculture development and model research of regional agriculture system. Finally, the principles of rural landscape planning in high intensive land use area were presented in the article: constructing highly efficient managed ecosystem, implementing intensified land management, rebuilding natural vegetation patches, controlling aimless expansion of artificial patches, reshaping beautiful residential environments and comfortable landscapes in harmony with natural systems, and arranging hill, water, forest, field and road as a whole.