基于NDVI的绿洲棉田土壤肥力质量评价方法研究

Study on Evaluation Methods for Soil Fertility in Oasis Cotton Field Based on the Normalized Difference Vegetation Index(NDVI)

以天山北坡典型国营农场棉田为研究对象,探讨基于归一化植被指数(NDVI)的棉田土壤肥力质量评价方法。将棉花不同生育期表征长势的NDVI作为评价指标对棉田土壤肥力质量进行评价,再将NDVI与少量理化测定的土壤样点数据(有机质、有效磷含量等)共同作为评价指标,结合地统计方法与遥感影像聚类算法进行评价;并与完全基于土壤样品理化测定数据的评价结果进行比较、探讨基于NDVI评价方法对土壤肥力质量评价结果的准确性与可靠性。研究证明将NDVI与少量理化测定的土壤样点数据作为评价指标,能显著提高评价结果与棉田实际土壤肥力状况的一致性。基于NDVI的土壤肥力质量评价方法快速、简便,其评价结果可为研究绿洲棉田土壤质量及农业结构调整规划、耕地质量保护等提供科学依据。

The cotton fields of typical state farms which set in the northem slope of Tianshan Mountain, were used to explore the soil fertility assessment method based on normalized difference vegetation index （NDVI）. Using the NDVI, which obtained dur- ing different cotton growth periods, as assessment index evaluate the soil fertility; then regard NDVI and soil physical and chemistry data such as soil organic matter content, available phosphorus content and so on, which come from small amount of cotton field soil samples, as the assessment index, the geostatistical methodology and remote sensing image clustering algorithm were used to evaluate the soil fertility. Comparing the two results with the one evaluated only by soil physical and chemistry da- ta, accuracy and reliability of the methods based on NDVI were studied. It could be concluded that： the method based on NDVI and a few soil physical and chemistry data can improve the accuracy and the consistent of reality significantly. The evaluation method for cotton soil fertility based on NDVI can evaluate rapidly and conveniently, and it will provide a scientific basis to the research on oasis cotton soil quality, agricultural restructuring plan and the cultivated land quality protection.