大比例尺度下土壤的养分特征及其空间变异性研究

Study on Soil Nutrient Characteristics and Its Spatial Variability in Large Scale

利用“网格”取样、土壤养分状况系统研究法、地统计学方法及地理信息系统技术探讨了湖北省 1个自然村 (光芒村 )土壤的养分特征及其空间变异性。结果表明 :(1)土壤有机质、NH4+ N和有效K的含量普遍较低 ,有效P的含量相对较高 ,土壤有效S、B、Mn和Zn的含量低于临界值的比例分别为 4 8.8%、4 9.6 %、6 4 .3%和73.6 % ;(2 )土壤 pH及有效养分含量的变异系数按如下顺序逐渐增大 :pH <Ca <Mg <有机质 <NH4+ N <Zn <Cu <K <Fe <S <Mn ,P <B ,变异系数小的土壤养分其频数分布多呈正态或近似正态分布 ,变异系数大的则呈现出明显的负偏峰分布特征 ;(3)NH4 N、有效P、K、Mg、B和Zn的空间变异主要受作物品种、施肥水平和管理方式等人为随机因素的影响 ,pH、Ca、S、Fe和Mn的空间变异则主要受成土母质、土壤类型、气候、水分条件等非人为活动的制约。

Soil nutrients characteristics and its spatial variabili ty of one natural village (Guangmang village) in Hubei Province were studied wit h grid sampling, systematic approach for soil nutrients status evaluation geo-s tatistics analysis and geographical information system (GIS) technique. Results showed as follows:(1) The soils were widely deficient of organic matter, N and K . The content of soil available P was relatively higher. The percentage of soil available S, B, Mn and Zn below critical value was 48.8%, 49.6%, 64.3% and 73.6% , respectively. (2) The variation coefficients of soil available nutrients were graded as pH<Ca<Mg<organic matter <NH 4 +-N<Zn<Cu<K<Fe<S<Mn , P<B.The frequency distribution of low variation coefficient showed the normal distribution characteristics and that of high variation coefficient showed obvi ously negative distribution characteristics. (3) For soil NH4 +-N, availab le P, K, Mg, B and Zn, their spatial variability was mainly influenced by random factors such as crop type, fertilization level and management.For pH, Ca, S, Fe and Mn, their spatial variability was mainly influenced by regional factors suc h as parent material, soil type, climate and water conditions.