东北典型黑土区耕地地力评价与障碍因素诊断

研究目的:从影响耕地地力的土壤管理、理化性质、土壤养分、剖面性状、立地条件和气候条件等6个方面选取13个评价指标对东北典型黑土区耕地地力进行综合评价,并在评价基础上进行障碍因素诊断,为今后定量化分析耕地地力障碍因素提供方法。研究方法:该研究运用层次分析法和模糊数学法等方法进行耕地地力评价,并引入障碍度模型对影响该区域耕地地力的障碍因素进行定量化分析。研究结果:(1)东北典型黑土区耕地地力整体呈现南高北低的趋势,其中以中等地(四、五、六、七等地)为主,占研究区总耕地面积的64.47%;其次为高等地(一、二、三等地),占研究区总耕地面积的28.31%;低等地(八、九、十等地)最少,只占研究区总耕地面积的7.22%;(2)对研究区评价指标体系中耕层厚度、有机质、有效磷、p H、灌溉能力、排涝能力6个指标进行障碍度分析,发现除有效磷和p H对耕地地力障碍作用不明显外,其他因素均有明显障碍作用,且障碍程度呈现一定的规律性。研究结论:(1)通过对研究区进行耕地地力评价,对东北典型黑土区的耕地数量和质量在空间分布特征上有了全面掌握,为今后耕地的合理利用提供了依据;(2)障碍度模型的引入为分析影响耕地地力的障碍因素提供了定量化的研究方法,为耕地地力保护和提升研究提供了方法支撑。

EVALUATION OF CULTIVATED LAND FERTILITY AND ITS OBSTACLE FACTORES DIAGNOSIS IN THE TYPICAL BLACK SOIL AREA OF NORTHEAST CHINA

This paper selected 13 evaluation indicators from the six aspects influencing cultivated land fertility, i.e., the soil management, physical and chemical properties, soil nutrient, soil profile character, site conditions and climate conditions to evaluate the fertility of cultivated land in typical northeast black soil area comprehensively, and then analyzed the obstacle factors on the basis of the evaluation using the methods such as Analytic Hierarchy Process (AHP) , fuzzy mathematics method, and obstacle degree model. The results showed that: (1) The cultivated land fertility of the typical black soil area of northeast China overall was low in north and high in south area. The level of cultivated land in the typical northeast black soil area was mainly middle (from fourth level to the seventh level), which accounted for 64.47% of the total cultivated land. While the high level cultivated land accounted for 28.31% of the total cultivated land; the area of the low level cultivated land accounted for 7.22% of the total cultivated land. (2)By analyzing the obstacle degree of the six indexes, i.e., the thickness of the middle layer cultivated land, organic matter, available P, pH value, irrigation, drainage in the study area, the effects of available p and pH were not obvious in typical black soil area. However, the other four factors had significant influences. It concluded that: the spatial distribution characteristics of the quantity and quality of the cultivated land in typical black soil of northeast area were found, which provided a basis for the rational utilization of cultivated land in the future. The obstacle degree model which was introduced in the research provided a quantitative analysis method in the cultivated land fertility protection and promotion in the future.