陇中黄土高原半干旱区苜蓿-作物轮作对土壤物理性质的影响  

Effect of lucerne-crop rotations on soil physical properties in the semi-arid Loess Plateau of Central Gansu

作　　者：宋丽萍[1] 罗珠珠[1,2] 李玲玲 蔡立群[1,2] 张仁陟 牛伊宁 

机构地区：[1]甘肃农业大学资源与环境学院,甘肃兰州730070 [2]甘肃省干旱生境作物学省部共建国家重点实验室,甘肃兰州730070

出　　处：《草业学报》2015年第7期12-20,共9页Acta Prataculturae Sinica

基　　金：国家科技支撑计划(2012BAD14B03);国家自然科学基金(31171513;41461067);甘肃省干旱生境作物学重点实验室-省部共建国家重点实验室培育基地基金(GSCS-2012-08);甘肃省科技计划(145RJZA208);甘肃省财政厅高校基本科研业务费项目(037-041014)资助

摘　　要：本研究通过设置在陇中黄土高原半干旱区苜蓿-作物轮作系统的长期定位试验,探讨了不同轮作模式对土壤物理性质的影响。6种轮作模式包括：苜蓿-苜蓿（L-L）、苜蓿-休闲（L-F）、苜蓿-小麦（L-W）、苜蓿-玉米（L-C）、苜蓿-马铃薯（L-P）和苜蓿-谷子（L-M）。结果表明,不同轮作模式下耕层土壤容重、孔隙度、土壤饱和导水率、土壤渗吸率、宏观毛管长度和有效孔径差异显著,苜蓿-作物轮作对土壤团聚体稳定性有一定影响,但不明显。L-F、L-W、L-C、L-P和L-M模式的土壤容重比L-L模式分别降低了6.86%,7.69%,6.22%,9.29%与10.17%。土壤渗吸率在L-F、L-W、L-C、L-P和L-M模式下分别比L-L模式提高了1.19,2.31,0.25,0.66和0.75倍,宏观毛管长度分别提高了3.73,2.92,1.49,2.62和1.15倍,有效孔径分别降低了79.43%,72.99%,56.71%,69.41%和56.35%,L-F、L-W和L-M模式土壤饱和导水率分别比L-L模式提高了0.32,1.52和0.33倍。轮作对土壤团聚体的影响主要表现在0～10cm和10～30cm的土层,其中L-C模式显著增加了土壤大团聚体含量,且增大了平均重量直径（MWD）和几何平均直径（GMD）值,提高了土壤的机械稳定性,L-P模式次之,但轮作在一定程度上降低了土壤水稳性团聚体的含量,L-F、L-W、L-C、L-P和L-M模式比L-L模式分别降低了33.44%,23.08%,7.36%,27.09%和20.29%。说明在黄土高原半干旱区,轮作有助于形成良好的土壤结构,改善土壤的渗透性能,促进土壤物理质量的提高。A long-term field experiment comparing the effects of different lucerne-crop rotations on soil physical properties was conducted at Dingxi,western Loess Plateau.Six rotation patterns [lucerne-lucerne （L-L）,lu-cerne-fallow （L-F）,lucerne-wheat （L-W）,lucerne-corn （L-C）,lucerne-potato （L-P）and lucerne-millet （L-M）]were compared.There were significant differences in soil bulk density,soil total porosity,soil saturated hydraulic conductivity,soil sorptivity,macroscopic capillary length and mean pore diameter among the six ro-tation patterns,but soil aggregate stability was not affected.Compared with those under L-L,soil bulk density under L-F,L-W,L-C,L-P and L-M was reduced by 6.86%,7.69%,6.22%,7.69% and 6.22% respective-ly,soil sorptivity increased by 1.19,2.31,0.25,0.66 and 0.75 times respectively,macroscopic capillary length increased by 3.73,2.92,1.49,2.62 and 1.15 times respectively and mean pore diameter reduced by 79.43%,72.99%,79.43%,69.41% and 56.35% respectively.Compared with L-L,soil saturated hydraulic conductivity under L-F,L-W and L-M increased by 0.32,1.52 and 0.33 times,respectively.The effect of rota-tion on soil aggregate mainly influenced the 0-10 and 10-30 cm soil layers.It was concluded that lucerne-crop rotations improved soil structure and permeability,improving soil physical quality in the semiarid areas on the Loess Plateau.

关 键 词：苜蓿-作物轮作 土壤容重 土壤饱和导水率 土壤团聚体稳定性 

分 类 号：S344.1[农业科学—作物栽培与耕作技术]