摘要
为了阐明紫花苜蓿草地土壤碳密度的年际变化规律,以长期定位试验的紫花苜蓿(Medicago sativa)草地为研究对象,通过大田测定和实验室分析,研究了不同生长年限紫花苜蓿草地土壤碳密度。结果表明:随着紫花苜蓿生长年限的增加,土壤有机碳含量增加,土壤碳密度提高。不同生长年限的苜蓿草地土壤有机碳含量、土壤有机碳密度在0~100cm土层的分布规律为随土层深度的增加而降低。不同年限的苜蓿草地土壤有机碳含量均为0~10cm表层最高,其土壤有机碳含量大小顺序为:1年龄(6.39g/kg)<2年龄(6.75g/kg)<3年龄(7.52g/kg)<4年龄(8.76g/kg)<5年龄(9.16g/kg)。不同年限的紫花苜蓿草地土壤有机碳密度差异显著(P<0.05),随着生长年限的增加,土壤有机碳密度显著提高,其中100cm的土壤有机碳密度平均值5年龄最高(8.38kg/m^2),比1年龄、2年龄、3年龄和4年龄分别增加了91.3%、56.1%、32.4%和8.1%。
The soil organic carbon density of alfalfa grassland growing 1-5years was investigated in order to explore the characteristics of interannual variations.Based on the long-term field experiment,the soil organic carbon density of alfalfa grassland were determined by quadrate method.The results indicated that soil organic carbon content and soil organic carbon density increased from 1-year to 5-year,but with soil layer depth increasing,the soil organic carbon content and soil organic carbon density decreased.The soil organic carbon content at0~10cm soil depth level were the highest on all alfalfa grassland,and the rank of the soil organic carbon content in different growth years was：1-year（6.39g/kg） 2-year（6.75g/kg）3-year（7.52g/kg） 4-year（8.76g/kg） 5-year（9.16g/kg）.Soil organic carbon density of alfalfa grassland in different growth years were significantly differences（P0.05）.The soil carbon density in 100 cm soil depth was significantly improved with growing years.The average soil organic carbon density of 5-year grassland was the highest（8.38kg/m）,as5-year grassland increased by 91.3%,56.1%,32.4% and 8.1% than 1-year,2-year,3-year and 4-year grassland,respectively.
出处
《草原与草坪》
CAS
CSCD
2015年第6期8-13,共6页
Grassland and Turf
基金
国家现代牧草产业技术体系建设专项(CARA-35)
国家自然科学基金面上项目(31372368)
中央级公益性科研院所基本科研业务费专项资金项目(1610322014009)
关键词
紫花苜蓿
年际变化
土壤有机碳
土壤碳密度
alfalfa
interannual change
soil organic carbon
soil carbon density
