摘要
【目的】探明褐土区典型县域耕地土壤肥力时空演变特征及主控因素,为合理施肥及土壤培肥提供科学依据。【方法】基于山西省寿阳县1983、2007和2017年的土壤肥力(包括土壤有机质、全氮、有效磷、速效钾含量和pH值)数据,采用内梅罗指数法计算土壤肥力综合指数;通过随机森林(RF)方法定量土壤肥力演变的主控因素;利用GIS和地统计学相结合的方法,确定土壤肥力综合指数及其主控因素的时空演变特征和分布格局。【结果】(1)1983—2017年间寿阳县耕地土壤肥力水平总体呈上升趋势,肥力综合指数由1.16增至1.42,增加了0.26。土壤肥力指标变化具有明显的阶段性,1983—2007年,有机质、全氮和速效钾增幅明显,年均增加量分别为0.09 g·kg^(-1)、0.0021 g·kg^(-1)和1.61 mg·kg^(-1),而有效磷增幅不显著;2007—2017年,有机质、全氮和有效磷增幅明显,年均增加量分别为0.20 g·kg^(-1)、0.01 g·kg^(-1)、0.24 mg·kg^(-1),而速效钾增幅不显著。(2)RF分析结果显示,1983年寿阳县耕地土壤肥力的主控因素为全氮和有机质,贡献率分别为75.3%和17.8%;2007年土壤肥力的主控因素则为速效钾、有效磷和全氮,贡献率分别为31.8%、27.1%和26.8%;2017年变为全氮、速效钾和有效磷,贡献率分别为31.8%、27.1%和26.8%。(3)寿阳县耕地土壤肥力主控因素的变化存在显著的空间差异特征。1983—2007年,全域土壤有机质整体呈现增加趋势;全氮除在西北部和中部降低外,在其他区域均呈增加趋势;有效磷则呈现北部降低、南部增加的变化特征;速效钾在全域呈增加趋势。2007—2017年,有机质在东南部增加较快,其他区域增加较慢;全氮则呈现在县域中部减少、其他区域增加的变化趋势;有效磷在县域东部下降,其他区域上升;速效钾则呈现在东部和西部下降、中部上升的空间变化特征。【结论】34年以来,寿阳县耕地土壤肥力总体呈上升趋势,有机质、全氮、有效磷和速效钾是影响土壤肥力演变的主控因素,有机质、全氮和有效磷在南部增长较快,速效钾则在东部增长较快。未来建议寿阳县采取全区尤其是中部增氮,全区稳磷控钾的养分调控策略。
【Objective】The main controlling factors of soil fertility and temporal and spatial evolution characteristics in typical county of cinnamon soil region were investigated,so as to provide the basis for scientific management of nutrients and soil fertilization.【Method】Based on the data of soil fertility,including soil organic matter(SOM),total nitrogen(TN),available phosphorus(AP),available potassium(AK)and pH,at Shouyang County in 1983,2007 and 2017,the Nemerow index method was used to calculate the comprehensive index of soil fertility,the random forest method was used to explore the main controlling factors of soil fertility,and the combined method of GIS and geostatistics was used to determine the temporal and spatial variability characteristics and the distribution patterns of the comprehensive index of soil fertility and its main factors.【Result】(1)The overall level of cultivated land soil fertility showed an upward trend in Shouyang County during the past 34 years,and the comprehensive index of soil fertility increased by 0.26,which changed from 1.16 to 1.42.The changes of soil fertility index were characterized by stages.From 1983 to 2007,the average annual increases of SOM,TN and AK were 0.09 g·kg^(-1),0.0021 g·kg^(-1) and 1.61 mg·kg^(-1),respectively,while the changes of AP were not significant.From 2007 to 2017,SOM,TN and AP increased significantly,with the average annual increases of 0.25 g·kg^(-1),0.01 g·kg^(-1) and 0.31 mg·kg^(-1),respectively,while the changes of AK were not significant.(2)The analysis results of the random forest model showed that,the main controlling factors of soil fertility were TN and SOM in 1983,with the importance of 75.3%and 17.8%,respectively.In 2007,the main controlling factors of soil fertility became AK,AP and TN,with the importance of 31.8%,27.1%and 26.8%,respectively.In 2017,the main controlling factors were TN,AK and AP,and the importance for the three factors were 31.8%,27.1%and 26.8%,respectively.(3)There were certain spatial differences in the main controlling factors of soil fertility.From 1983 to 2007,SOM increased in the whole county;TN decreased in the northwest and central regions,but increased in other regions;AP decreased in the north regions,but increased in the south regions;AK increased in the whole county.From 2007 to 2017,SOM increased fast in the southeast regions but slow in other regions;TN decreased in the middle regions but increased in other regions;AP decreased in the east regions,but increased in other regions;AK decreased in the east and west regions,but increased in the central region.【Conclusion】After 34 years,the cultivated land soil fertility of Shouyang County has been improved,and SOM,TN,AP and AK were the main controlling factors affecting the soil fertility variability.SOM,TN and AP increased fast in the south regions,while AK increased fast in the east regions.It was suggested that the whole Shouyang County still needed to increase the application of nitrogen fertilizer moderately,especially in the central region,and stabilize the application of phosphate fertilizer,while control the application of potassium fertilizer in the future.
作者
申桐
王恒飞
杜文波
周怀平
王瑞
张建杰
靳东升
徐明岗
SHEN Tong;WANG HengFei;DU WenBo;ZHOU HuaiPing;WANG Rui;ZHANG JianJie;JIN DongSheng;XU MingGang(College of Resources and Environment,Shanxi Agricultural University,Taigu 030800,Shanxi;Academy of Eco-Environment and Industrial Technology,Shanxi Agricultural University/Shanxi Province Key Laboratory of Soil Environment and Nutrient Resources,Taiyuan 030031;Shanxi Farmland Quality Monitoring and Protection Center,Taiyuan 030001)
出处
《中国农业科学》
CAS
CSCD
北大核心
2023年第21期4259-4271,共13页
Scientia Agricultura Sinica
基金
科技基础资源调查专项(2021FY100501)
山西省科技合作交流项目(202104041101002)
山西省博士毕业生来晋奖励科研项目(SXBYKY2022083)。
关键词
土壤肥力
时空演变
褐土区
主控因素
寿阳县
soil fertility
spatial-temporal variability
cinnamon soil area
main controlling factors
Shouyang County
