长期保护性耕种方式对农田表层土壤性质的影响  

Long-term effects of tillage systems and rotation on selected soil properties in cropping zone of Southern NSW, Australia

作　　者：张国盛[1] K Y Chan G D Li D P Heenan 

机构地区：[1]云南大学生命科学学院,昆明650091 [2]澳大利亚新南威尔士州初级产业部E H Graham农业创新中心 [3]澳大利亚新南威尔士州初级产业部Wagga Wagga农业研究所

出　　处：《生态学报》2008年第6期2722-2728,共7页Acta Ecologica Sinica

基　　金：澳大利亚ATSE Crawford基金会~~

摘　　要：研究了不同耕种方式对澳大利亚同一地区3种土壤表层（0-5cm）理化性质的作用，以揭示保护性耕作对土壤质量恢复的影响。结果表明：免耕穴播／保留残茬（DD／SR）、多年生人工草地（PP）和自然草地（NP）表层土壤的〉2mm水稳性团聚体含量、全氮、有机碳含量、田间持水量均显著高于其相应对照传统耕作／秸秆焚烧（CC／SB）、人工草地／作物轮作（PPC）和耕作（CT）的；土壤全氮含量、田间持水量分别与有机碳含量之间有极显著的正相关关系（r=0．994＊＊，r=0.996＊＊，n=6），而受土壤质地等因素的影响较小；在同一类型的土壤上，土壤有机碳含量与水稳定性团聚体含量之间存在显著的相关性；在不同试验区，耕作措施对表层土壤容重和孑L隙分布的影响存在较大差异；秸秆焚烧和施用石膏对表层土壤的pH及交换性阳离子含量有较大的影响。研究表明长期保护性耕作、草田轮作或多年生草地有利于提高表层土壤有机碳含量和结构稳定性，从而改善土壤的供肥供水能力。Different tillage and cropping practices can change soil properties which in turn can affect crop growth and the environment. The objective of this study was to investigate the effect＇ of different tillage and pasture rotation systems on pH, soil organic matter （SOC）, total N （TN） and selected physical properties of the surface layer （0-5 cm） of 3 soils in Wagga Wagga, New South Wales, Australia. In 0-5 cm layer, % 〉 2mm water stable macro-aggregates, soil organic carbon （SOC）, and total nitrogen （TN） were significantly higher in the treatments of direct drilled/stubble retained （DD/ SR）, perennial pasture （PP） and nature pasture （NP）, than the corresponding contrasting treatments of conventional cultivation/stubble burnt （CC/SB）, pasture/crop rotation （PPC） and conventional cultivation （CT） respectively. At all 3 experiment sites, conservation tillage had the effect of changing the nature of organic carbon resulting in higher labile and slow organic carbon fractions. Soil organic carbon concentration was significantly related to total nitrogen（ r = 0.994 ＊＊ , n = 6）. At each experiment site, SOC was significantly positively correlated with % 〉 2 mm macro-aggregates but there was no correlation when data of all 3 sites were combined. This aggregation, other factors like clay content were also involved indicated that SOC was not the only factor affecting soil The effects of tillage practice on bulk density （BD） and porosity varied at different experiment sites. At one of the sites, BD was significantly higher and 〉 60μm porosity was significantly lower under conventional tillage practice compared to conservation tillage. However, results of the other two sites were inconsistent. Field capacity water content was significantly affected by tillage practices and significantly correlated with SOC within 3 soils （ r = 0.996 ＊＊ , n = 6）. This suggested that soil water holding capacity was mainly affected by SOC. Stubble burning and gypsum applicatio

关 键 词：保护性耕作 有机碳 团聚体 田间持水量 PH 

分 类 号：S345[农业科学—作物栽培与耕作技术] S158[农业科学—农艺学]