为保护哈尼梯田人工湿地、维护区域生态安全、传承梯田农耕文明,以元阳县梯田为研究对象,通过野外地质调察、查阅区域地质调查报告和区域岩石性质以及土壤性质,利用GIS空间技术分析了梯田空间分布及自然影响因素,旨在进一步明晰梯田空间分布与各自然影响要素对其影响机理,为梯田的管理保护与研究提供参考。结果 表明:(1)地形决定了梯田的形态和面积规模。在海拔800～1 500 m、坡度0°～15°的亚热带平缓山区沿等高线分布了梯田总面积的73.23%,75.35%。(2)岩性通过影响岩石保水蓄水的水理性质进而影响到梯田的完整性; 研究区中部的片麻岩类岩石基岩裂隙不甚发育储水性能良好,片麻岩类占岩石面积的51.49%,分布了梯田的58.99%; 其他区域主要为(石)灰岩及砂页岩类,空隙大,下渗严重。(3)土壤的矿物成分、理化性状不尽相同,制约着水稻的生长发育,其粘性、保水性以及可塑性影响着梯田的景观格局; 中部梯田区的红壤(麻黄红土)和赤红壤(麻黄赤红土)多为黏壤土,土体厚质地轻且养分含量较高,在长期人为熟化下土质粘重易保水保肥; 其他地区的土壤大多土体厚薄不一、层次分异明显,蓄水蓄肥能力较差、耕性不良。研究结果为梯田的开发利用和保护提供科学依据。
In order to protect artificial wetland of the Hani Rice Terrace, maintain regional ecological security, and inherit the terraced farming civilization, taking the Rice Terrace of Yuanyang County as the research site, we used a spatial analysis technology of GIS to analyze and study the spatial distribution and natural influence factors of terraces through field geological survey, consulting regional geological survey report and rock properties and soil properties, to further clarify the spatial distribution of terraces and mechanism of natural influencing factors on terrace, and to provide the reference for the management and research of terraces. The results show that:(1)the topography determines the shape and area scale of the terraces, 73.23% and 75.35% of the total area of terraces distribute along the contour lines at the subtropical gentle mountain area with the elevations of 800～1 500 m and slope gradient of 0°～15°, respectively;(2)the lithologic properties affect the integrity of terraced fields through affecting the water quality of rock retaining and storing water; the gneiss bedrock fracture is poorly developed, and has the good water storage performance in the middle part of the study area, the gneiss accounts for 51.49% of the rock area and 58.99% of the terrace, the rest of the study area is mainly dominated by limestone and sand shale with large void space and serious infiltration;(3)the mineral composition and physical and chemical properties of the soil are different, which restricts the growth and development of rice, the viscosity, water retentiveness and plasticity of soil affect the landscape pattern of terraces; the red soil(red soil of ephedra)and lateritic red soil(lateritic red soil of ephedra)in the middle of terrace area are mostly clay loam with the thick pedon, loamy texture and rich nutrients; under the condition of long-term artificial ripening, the soil is sticky and soil moisture and fertility properties are well preserved; most of the soils in other areas have different thicknesses, stratify obviously, have the poor water storage and fertilizer capacity, and poor farming performance. These results can provide a scientific basis for the development, utilization and protection of terraces.
