曲靖植烟土壤养分空间变异及土壤肥力适宜性评价

Soil nutrients spatial variability and soil fertility suitability in Qujing tobacco-planting area

采用GPS技术在云南曲靖烟区布置了2088个采样点,测定其耕作层(0～20 cm)土壤主要养分含量,利用经典统计方法和地统计学方法对植烟土壤养分状况的总体特征和空间变异特征进行分析,并采用模糊数学方法对植烟土壤肥力适宜性进行综合评价.结果表明:曲靖植烟土壤pH、有机质、有效硫和水溶性氯含量适宜,全氮和碱解氮含量偏高,速效钾、有效钙、有效镁、有效铜、有效铁、有效锌、有效钼和有效锰含量丰富,速效磷含量中等,全磷、全钾和有效硼含量偏低;区域内植烟土壤养分指标均表现为各向异性分布,其中速效磷和有效硼的空间变异主要受随机性因素的影响,其他养分指标的空间变异是结构性因素和随机性因素共同作用的结果.植烟土壤肥力适宜性指数为优的区域缺乏,为良的区域占8.0%,一般的区域占51.6%,中等的区域占39.0%,为差的区域占1.4%.

By adopting GPS technique,2088 sampling sites were installed in the tobacco-planting area of Qujing City,Yunnan Province,with 0-20 cm soil samples collected to determine their main nutrients contents.The overall characteristics and spatial variability of the tobacco soil nutrients were analyzed by classic statistics and geo-statistics,and the soil fertility suitability in planting tobacco was evaluated by the methods of fuzzy mathematics.In the study area,soil pH and soil organic matter,available S,and water-soluble Cl contents were appropriate,soil total N and alkali-hydrolyzable N contents were too high,soil available K,Ca,Mg,Cu,Fe,Zn,Mo,and Mn contents were abundant,soil available P content was at medium level,while soil total P and K and available B contents were insufficient.All the nutrient indices presented anisotropic distribution,among which,the spatial variability of soil available P and B was mainly caused by random factors,and that of other nutrients was caused by the co-effects of structural and random factors.The spatial distribution map of soil fertility suitability index（SFI） showed that there was no the excellent grade region for tobacco-planting,good grade region accounted for 8.0%,general grade region accounted for 51.6%,moderate grade region accounted for 39.0%,and low grade region accounted for 1.4%.