基于植被覆盖率的农村居民点整理潜力估算及实证

Estimation and validation of rural residential land consolidation potential based on vegetation coverage rate

为合理估算农村居民点整理潜力,该文提出基于植被覆盖率的农村居民点整理潜力测算新思路。借助植被覆盖率对农村居民点斑块进行分类,通过分析抽样农村居民点斑块的植被覆盖与内部用地结构得到整理潜力修正系数,从而建立基于植被覆盖率修正的农村居民点整理潜力估算模型,并以北京市门头沟区为例展开实证研究。研究结果表明,门头沟区无整理潜力的农村居民点占大多数,具有整理潜力的农村居民点主要集中在经济相对落后的乡镇,并且这部分农村居民点多远离主干道;山区具有中、高整理潜力的农村居民点略多于平原、浅山区,而低整理潜力的农村居民点明显多于平原、浅山区;门头沟区规划整理的农村居民点内部包含有大量农用地,其中建设用地比例只占63.19%～71.54%,但是,第二次土地调查将整个农村居民点都作为建设用地调绘;因而,一些不考虑植被覆盖修正的农村居民点整理潜力测算方法夸大了整理潜力,放大了城乡建设用地增减挂钩的效果。该文为进一步合理估算农村居民点整理理论潜力提供参考。

To acquire proper rural residential land consolidation potential, a new approach for estimating rural residential land consolidation potential based on vegetation coverage rate was developed in this study. Firstly, vegetation coverage in research area was classified using FCD model（forrest canopy density mapping model）, which was derived from bio-physical model and developed during ITTO（International Tropical Timber Organization） Project PD32/93 Rev.2（F）, ＂Rehabilitation of Logged-over Forests in Asia-Pacific Region, Sub-project III＂（JOFCA 1991,1993）. Then, high resolution remote sensing （RS） images （in 2009） of typical village samples selected by stratified sampling method were obtained via Google Earth （GE） platform. And further classification was performed to gain inner land use structure of village samples by visual interpretation on the support of ENVI 4.8 software. Using ArcGIS 10.0, relationship between vegetation coverage and inner land use structure of rural residential land was determined after layer overlapping. On the basis of rural residential land consolidation potential estimation model introduced in ＂key points for county level land development and consolidation specific plan compilation＂and modified coefficients generated by a series of calculation, modified model based on vegetation coverage was established. Then the case study was carried out in Mentougou District, Beijing city. The results indicated that most rural residential lands in Mentougou District exhibited little consolidation potential. Whereas the rural residential land distributed far from main roads, the county of low level economy manifested consolidation potential. Rural residential land in mountainous areas of medium and high level consolidation potential was more than that in plain and low mountainous areas, and less than that of low level consolidation potential. Construction land in rural residential land only accounted for 63.19%-71.54%. However, rural residential land was classified as construction land in the second national land survey based on collective land use rights without taking land cover into account, which exaggerated the real consolidation potential in urban-rural construction land transfer. Furthermore, the lack of modified consolidation potential estimation will destroy farmland status quo and aggravate land quality.