中度和剧烈侵蚀黑土作物地上与地下生长发育的差异  

Difference of crop's aboveground and underground growth between moderately and severely eroded black soil

作　　者：张珊珊[1] 谢云[1] 刘刚[1] 闫静雯[1] 翟俊瑞 赵相杰 王翔鹰[1] Zhang Shanshan Xie Yun Liu Gang Yan Jingwen Zhai Junrui Zhao Xiangjie Wang Xiangying(State Key Laboratory of Earth Surface Processes and Resource Ecology, School of Geography, Beijing Normal University, 100875,Beijing, China)

机构地区：[1]北京师范大学,地理学与遥感科学学院,地表过程与资源生态国家重点实验室,北京100875

出　　处：《中国水土保持科学》2016年第5期29-36,共8页Science of Soil and Water Conservation

基　　金：国家自然科学基金“东北黑土区土壤侵蚀对‘作物产量-土壤水分响应关系’的影响”(41371271);水利部公益性行业科研专项经费项目“典型黑土区坡耕地土壤侵蚀危险程度研究”(201501012)

摘　　要：土壤侵蚀导致黑土生产力下降已成为不争的事实,以往多采用盆栽、池栽或小区实验,主要关注侵蚀对地上生物量和产量的影响,缺少侵蚀对根系及其与地上生物量关系影响的研究。本研究选择不同侵蚀强度黑土的大田,于2014—2015同时观测地上和地下生长过程及产量,研究侵蚀对二者及其相互关系的影响。结果表明:大田情况下,剧烈侵蚀黑土导致玉米减产32.7%,大豆减产57.1%。与根系生长相比,侵蚀对地上生物量的影响更为显著,且主要在生殖生长期以后影响较大。从地上生物量与根系之间的关系看,随侵蚀加剧,根冠比增加。剧烈侵蚀玉米和大豆根冠比在全生育期平均增加41.8%和67.1%。2种作物的根系分布随土壤深度增加呈指数规律递减,侵蚀导致作物根系趋向深层——中度侵蚀根系的表层比例较高,剧烈侵蚀根系的深层比例较高。[Background] Black soil region is one of important grain production bases in China.However,the decrease of crop production has been obvious due to soil erosion by long-term cultivation.Previous researches focused on impacts of erosion on aboveground biomass and yields by using pot,pool or plot experimental methods,and paid little attentions to impacts on root growths. This study is to clarify the response of aboveground biomass,yields,root growths and their relationships to eroded black soils.[Methods] Both moderately and severely eroded black soil fields in Heshan farm of Heilongjiang Province were selected for the study,and the aboveground biomass dry weight（ BDW）,leaf area index（ LAI）,and root growths every 10 days during different growth stages for maize and soybean in 2014 and2015 were measured,and yields were obtained during the harvest time. A root sampling method of 5holes for each soil layer with 15 cm depth by using a soil auger was proposed,and the root biomass and length were measured after washing root samples. [Results] The soil erosion significantly reduced the yield of maize and soybean. Compared with moderately eroded soil,severe erosion caused the reduction of yield by 32. 7% for maize,and 57. 1% for soybean. Soil erosion caused more obvious effects on the aboveground biomass,especially during the reproductive period,comparing with impacts on root growth.Severe erosion caused the decrease of BDWby 20. 5% and 51. 4% for maize during the middle and later growth respectively,and 21. 9% and 55. 7% for soybean,relative to moderately eroded soil. The growing rate of BDWalso was more sensitive to soil erosion than that of RMD. From view of the impacts of erosion on the relationship between aboveground and underground biomass,the root shoot ratio increased with more severe erosion. The root shoot ratios of maize increased by 42. 4%,25. 8%,57. 1% during the early,middle and later growth stages relative to the moderate soil erosion condition,and increased by 62%,54. 2%,85% during the early,middle

关 键 词：黑土 土壤侵蚀 玉米 大豆 地上生物量 根系生长 

分 类 号：S158.1[农业科学—土壤学]