海伦黑土有机碳和养分含量30年变化特征  

Changes of soil organic carbon and nutrients in Hailun Mollisols in the past thirty years

作　　者：尤孟阳[1] 郝翔翔[1] 李禄军[1,2] YOU Mengyang;HAO Xiangxiang;LI Lujun(National Field Observation and Research Station of Hailun Agroecosystems,Northeast Institute of Geography and Agroecology,Chinese Academy of Sciences,Harbin 150081,China;University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院东北地理与农业生态研究所,海伦农田生态系统国家野外科学观测研究站,黑龙江哈尔滨150081 [2]中国科学院大学,北京100049

出　　处：《土壤与作物》2020年第3期211-220,共10页Soils and Crops

基　　金：中国科学院基础前沿科学研究计划(ZDBS-LY-DQC017);美丽中国生态文明建设科技工程专项(XDA23060502);中国科学院战略性科技先导专项(XDA05050501)。

摘　　要：黑土是支撑东北地区粮食高产稳产的基础。近年来黑土质量退化、肥力下降,已严重威胁粮食的可持续生产能力。土壤有机碳和养分含量的演变特征是评价土壤肥力变化的重要指标。本文以位于黑土带腹地、具有代表典型黑土的海伦市为例,结合第二次全国土壤普查资料和实际调查数据,系统分析了30年来农田黑土有机碳和养分的变化规律及其相互关系,为改善黑土农田管理措施提供科学依据。结果表明,与80年代相比,黑土农田表层土壤有机碳含量下降了12%,其中厚层黑土下降幅度最大(22%)。土壤养分也呈现不同的变化趋势,表层黑土碱解氮和速效钾分别下降了33%和43%,有效磷增加了48%。碱解氮在厚层、中层和薄层黑土中的下降速率分别为3.25 mg·kg^-1·a^-1,2.24 mg·kg^-1·a^-1和1.64 mg·kg^-1·a^-1;速效钾的下降速率分别为4.11 mg·kg^-1·a^-1,3.53 mg·kg^-1·a^-1和4.68 mg·kg^-1·a^-1;不同类型黑土有效磷含量略有增加,增加速率分别为0.14 mg·kg^-1·a^-1,0.53 mg·kg^-1·a^-1和0.22 mg·kg^-1·a^-1。相关性分析显示,土壤有机碳与碱解氮和速效钾含量显著正相关,与有效磷相关性不显著。针对当前黑土农田土壤碳和养分状况,应采取固碳、减磷、补钾和提高氮肥利用率的管理措施。High fertility of black soils(Mollisol)is the foundation for supporting high and stable grain production in Northeast China.However,the degradation of soil quality and decline in soil fertility seriously threaten the sustainable grain production in recent years.The characteristics of changes in soil organic carbon(SOC)and nutrient content play a key role in evaluating changes in soil fertility.To access the changes in SOC and nutrients and their interactions in surface soil layer following agricultural production during the past 30 years,soil samples were collected in croplands of Hailun county,which is located in the center of typical black soil region.The data and sampling locations referred to the Second National Soil Surveys of Heilongjiang Province conducted in the 1980s.The results showed that SOC content decreased by 12%compared to that in 1981,with more carbon loss in thick layer black soil(by 22%)than in medium layer and thin layer black soils.Over the past 30 years,soil alkali-hydrolyzable nitrogen and available potassium decreased by 33%and 43%,respectively,while available phosphorus increased by 48%.Moreover,soil alkali-hydrolyzable nitrogen decreased by 3.25,2.24 and 1.64 mg·kg^-1·a^-1 in thick layer,medium layer and thin layer black soils,respectively;and soil available potassium decreased by 4.11,3.53 and 4.68 mg·kg^-1·a^-1,respectively.While soil available phosphorus content increased slightly,with an increasing rate of 0.14,0.53 and 0.22 mg·kg^-1·a^-1,respectively.The SOC was positively correlated with alkali-hydrolyzable nitrogen and available potassium,but was not significantly correlated with available phosphorus.In terms of the status of soil carbon and nutrients of black soils,agricultural management practices should be adopted,focusing on carbon sequestration,phosphorus use reduction,potassium supplementation,and nitrogen use efficiency improvement.

关 键 词：土壤有机碳 土壤养分 秸秆还田 黑土 

分 类 号：S158.5[农业科学—土壤学]