江西省耕地土壤碳氮比空间变异特征及其影响因素  

Spatial Variability of C-to-N Ratio of Farmland Soil in Jiangxi Province

作　　者：江叶枫 郭熙[1,2] 孙凯 饶磊[1,2] 李婕 王澜珂[1,2] 叶英聪 李伟峰 

机构地区：[1]江西农业大学国土资源与环境学院,南昌330045 [2]江西省鄱阳湖流域农业资源与生态重点实验室,南昌330045

出　　处：《环境科学》2017年第9期3840-3850,共11页Environmental Science

基　　金：国家自然科学基金项目(41361049);江西省自然科学基金项目(20122BAB204012);江西省赣鄱英才"555"领军人才项目(201295)

摘　　要：以江西省2012年测土配方施肥项目采集的16 582个耕地表层(0~20 cm)土壤样点数据,运用普通克里格和回归分析方法,对江西省土壤碳氮比(C/N)空间变异特征及其影响因素进行分析.结果表明江西省土壤C/N在2.98~52.67之间,平均值为11.72,变异系数为25.17%,呈中等变异性.经半方差分析,土壤C/N的块金效应为88.44%,其空间变异受结构性和随机性因素共同影响,但随机性因素的影响更大.土壤C/N空间分布较为平滑,高值区主要分布在九江市彭泽县、萍乡市上栗县和抚州市乐安县.地形因子、耕地利用方式、成土母质、土壤类型和氮肥施用量对土壤C/N空间变异影响均显著(P<0.05),但影响程度不一.地形因子可解释0.3%的土壤C/N空间变异,耕地利用方式的独立解释能力为1.4%,成土母质的独立解释能力为2.4%,土类、亚类和土属的独立解释能力分别为2.7%、3.6%、5.5%.氮肥施用量对土壤C/N空间变异的独立解释能力最高,为33.4%,是引起江西省土壤C/N空间变异最主要的因素.Spatial variability of soil carbon-to-nitrogen ratio（ C/N） at the provincial scale was analyzed using ordinary kriging methods. The effects of the factors influencing C/N were quantified by regression analysis based on 16,582 points of surface soil samples（ 0-20 cm） collected during the project of soil-test-based formulated fertilization in Jiangxi Province in 2012. The results showed that soil C/N ranged from 2. 98 to 52. 67,with an average of 11. 72. The coefficient of variation was 25. 17%,suggesting moderate variability. The nugget-to-sill ratio was 88. 44%,meaning that the stochastic factors played a more important role in the spatial variability of soil C/N between the structural and stochastic factors. The spatial distribution of soil C/N was relatively smooth and the high-value areas were mainly distributed in Pengze County-Jiujiang City,Shangli County-Pingxiang City,and Lean CountyFuzhou City. The terrain factors,farmland-use type,parent material,soil type,and the level of nitrogen fertilizer had significant impacts on the spatial variability of soil C/N（ P〈0. 05）,but the degree of influence was different for each factor. Soil C/N indicated a significant positive Pearson＇s correlation with elevation and the slope of slope（ P〈0. 05）. The terrain factors explained 0. 3% of the spatial variability of soil C/N and the farmland-use could explain 1. 4%. The explanatory power of soil groups,subgroups,and soil family were 2. 7%,3. 6%,and 5. 5% respectively. The level of nitrogen fertilizer could explain 33. 4% of the spatial variability of soil C/N,which showed that the amount of nitrogen fertilizer was the main factor that controls the spatial distribution of soil C/N.

关 键 词：江西省 土壤碳氮比 空间变异 影响因素 氮肥施用量 

分 类 号：X144[环境科学与工程—环境科学]