矿区排土场苜蓿地土壤生态化学计量特征  

Soil ecological stoichiometric characteristics of Medicago sativa land of mining area waste dumps

作　　者：王东丽 张子倩 刘阳 赵晓亮 连昭 于百和 王东[2] WANG Dongli;ZHANG Ziqian;LIU Yang;ZHAO Xiaoliang;LIAN Zhao;YU Baihe;WANG Dong(College of Environmental Science and Engineering,Liaoning Technical University,Fuxin 123000,Liaoning,China;College of Mining,Liaoning Technical University,Fuxin 123000,Liaoning,China)

机构地区：[1]辽宁工程技术大学环境科学与工程学院,辽宁阜新123000 [2]辽宁工程技术大学矿业学院,辽宁阜新123000

出　　处：《草业科学》2022年第7期1323-1332,共10页Pratacultural Science

基　　金：辽宁省自然资源科技创新项目“辽西矿区土壤土壤改良与生物修复技术及应用研究”;内蒙古自治区科技计划项目(201701024)。

摘　　要：紫花苜蓿(Medicago sativa)因其较强的适生性与抗逆性,成为半干旱矿区排土场主要的生态重建植物,但在排土场恢复过程中常出现提前衰退现象。为探明黄土区排土场苜蓿恢复过程中是否受土壤养分的限制,选取不同恢复年限(2、4、6、10年)苜蓿地为研究对象,以新排土为对照,研究0-60 cm土壤中有机碳、全氮、全磷含量与化学计量特征及关系。结果表明:土壤有机碳、全氮、全磷含量随恢复年限增加变化规律不一致,分别在种植10、6和2年时最高,在种植2、4和10年时最低;随土层深度的变化,土壤有机碳、全氮含量整体呈下降趋势。在苜蓿恢复过程中,C꞉N与C꞉P整体上呈“W”型的变化规律,土壤N꞉P呈“V”型变化规律;恢复6和10年时土壤C꞉P和N꞉P均随土层加深而下降。土壤有机碳含量与氮、磷含量之间均具有极显著正相关性(P<0.01),矿区排土场土壤养分主要与土壤有机碳含量关系密切,土壤全磷含量不受其他养分影响。在半干旱黄土区排土场,苜蓿恢复模式具有一定的土壤肥力恢复作用,恢复过程中不同程度地受氮、磷养分限制,建议加强科学施肥管理或在恢复4至6年时及时利用。Planting of Medicago sativa has become the main ecological reconstruction model for the revegetation of waste dumps in semi-arid mining areas,owing to this plant’s strong adaptability and stress resistance.However,populations have been found to undergo premature declines during the restoration process.To determine whether M.sativa restoration in loess areas is restricted by a deficiency in soil nutrients,we selected sites that had undergone 2,4,6,and 10 years of restoration,along with newly dumped soil used as a control,and examined the C,N,and P contents and stoichiometric characteristics of the 0-60 cm soil layer.The results showed that the soil C,N,and P contents underwent inconsistent changes with a prolongation of the restoration period,with contents being highest after 10,6,and 2 years,and lowest after 2,4,and 10 years,respectively.Within the vertical soil profile,the soil C and N content generally showed a decreasing trend with soil depth.As M.sativa restoration proceeded,the C꞉N and C꞉P ratios showed a general“W”-shaped trend,whereas the N꞉P ratio showed a“V”-shaped trend.Both soil C꞉P and N꞉P ratios decreased with an increase an soil depth after 6 and 10 years.There was a very significant positive correlation between soil organic carbon and N and P contents(P<0.01).Nutrients in soil of the mining area dumping ground were mainly closely related to soil organic carbon,whereas the total P content of soil was largely unaffected by other nutrients.In the semi-arid loess area,the mode of M.sativa restoration has a certain effect on restoring soil fertility.During the restoration process,plant growth is limited to varying extents by N and P deficiencies.Accordingly,to rectify this problem,we would recommend enhancing scientific fertilization management,or at least carrying out fertilization during the period between 4 to 6 years after commencing restoration.

关 键 词：黄土区 露天煤矿 生态重建 紫花苜蓿 土壤碳氮磷 养分限制 土壤改良 

分 类 号：S541.9[农业科学—作物学]