摘要
为探讨植被种植过程中土壤–植被生态系统养分动态变化规律,本研究以黄土高原多年生紫花苜蓿(Medicago sativa)为研究对象,分析了不同生长年限(种植1、10、20和30年)苜蓿草地土壤与植物养分含量变化及生态化学计量学特征。结果显示,1)土壤有机C和全N含量随种植年限的增加呈先增大后减小的趋势;在0–200 cm土层中,土壤C和N的垂直分布具有一致性,含量随着土层的加深而逐渐减少,并在30 cm以下基本保持稳定;土壤P的含量随着土层的加深基本保持稳定;土壤C∶N,C∶P和N∶P均随苜蓿种植年限的增长呈先增加后减少的趋势,种植10年达到最大值。2)苜蓿叶片C、N、P含量的变化规律与土壤养分变化规律相似,种植10年达到最大值;叶片C∶N、C∶P、N∶P随种植年限的增加均先下降后回升。3)土壤化学计量特征与植物化学计量特征无显著相关关系(P> 0.05)。研究结果表明,当苜蓿种植到10年之后,应采取一定的管理措施来改善土壤质量以保证苜蓿正常生长。
To investigate the changes inw nutrients in soil-vegetation ecosystems,Medicago sativa at different ages(1,10,20,30 years)was selected to analyze variations in the nutrient content and characteristics of eco-chemical stoichiometry.The results showed that:1)the content of soil organic carbon(SOC)and total nitrogen(TN)first increased and then decreased as age increased,the vertical distribution of SOC and TN at a soil depth of 0–200 cm was consistent at all alfalfa grasslands,and the content of SOC and TN at a soil depth of 0–30 cm was higher than that at 30–200 cm.However,the content of soil total phosphorus(TP)was stable throughout the soil layer.The ratios of soil C∶N,C∶P,and N∶P showed similar dynamic patterns to soil carbon and nitrogen.2)The content of C,N,and P in the leaf was similar to that in soil,with maximum values observed at 10 years.The ratios of leaf C∶N,C∶P,and N∶P first decreased and then increased.3)There was no significant correlation between the stoichiometry characteristics of the soil and plant(P>0.05).These results indicate that after 10 years,some management measures should be taken to improve the quality of soil and growth of alfalfa.
作者
赵如梦
张炳学
王晓霞
韩凤朋
ZHAO Rumeng;ZHANG Bingxue;WANG Xiaoxia;HAN Fengpeng(Colleges of Resources and Environmental Science,Northwest A&F University/State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau,Yangling 712100,Shaanxi,China;Institute of Soil and Water Conservation,CAS & MWR,Yangling 712100,Shaanxi,China)
出处
《草业科学》
CAS
CSCD
2019年第5期1189-1199,共11页
Pratacultural Science
基金
国家自然科学基金(41471437)
国家重点研发计划(2016YFA0600801
2017YFC0504504)
科技基础性工作专项(2014FY210100)
中国科学院科技服务网络计划(KFJ-STS-ZDTP-012)
中国科学院"西部青年学者"(XAB2016A04)
