摘要
利用氯仿熏蒸浸提法研究了南方双季稻区6种母质发育的土壤种植黑麦草(Lolium multiflroum Lam.)作为冬季覆盖作物对土壤微生物量碳、氮周年动态的影响。结果表明:土壤类型对微生物量碳、氮影响显著(P<0.05)。其中板页岩土壤微生物量碳含量最高,为450.8mg/kg;河沙泥微生物量碳最低,为60.8mg/kg,由大到小排列为:板页岩>紫土>花岗岩>红壤>石灰岩>河沙泥。不同取样时期内土壤微生物性状有显著差异(P<0.05),种植黑麦草各处理比对照(冬闲)显著提高了土壤有机质含量和微生物量碳、氮。所有处理表现出相似的微生物量周年变化趋势:水稻成熟期高于分蘖期(P<0.05),晚稻生长季节大于早稻季节。土壤微生物量受土壤类型、土壤营养元素含量和种植制度的综合影响,微生物活动与作物生长有关。冬季种植黑麦草可显著提高土壤有机质含量和微生物量(P<0.05),在有机质分解快、有效养分含量低的土壤中效果更显著。
In the current study, the effects ofryegrass （Lolium multiflrourn Lam.） planted as a winter cover crop on soil microbial biomass C and N in six soil types were evaluated by a chloroform-fumigation-extraction method in southern China＇ s double-rice region. According to the results, soil type and sampling date have significant effects （P〈0.05） both on soil microbial biomass C and N. In the six different soil types the highest soil microbial biomass C was found in Yellow clayey soil （YCS） and the lowest value in Alluvial sandy soil （ASS）, values averaged across the year were 450.8 and 60.8 mg/kg, respectively. When arranged in a decreasing order, it was Yellow clayey soil （YCS） 〉 Purple clayey soil （PCS） 〉 Granitic sandy soil （GSS） 〉 Red clayey soil （RCS） 〉 Grey clayey soil （GCS） 〉 Alluvial sandy soil （ASS）. Ryegrass increased soil organic matter and microbial biomass C and N significantly （P〈 0.05） compared with CK（fallow）. All the treatments followed a similar seasonal trend in soil microbial biomass： greater values were found at maturity stage and at middle-rice season while the lower values were found at stage and at early-rice season. We thus concluded that soil microbial activities were related to crop stages and the microbial biomass was affected by a complicity of factors including soil type, nutrient availability and crop management. Ryegrass could increase soil organic matter and microbial biomass significantly, especially in soils with a high organic degradation rate and low available nutrient contents.
出处
《中国农学通报》
CSCD
北大核心
2009年第3期225-229,共5页
Chinese Agricultural Science Bulletin
基金
国家自然基金项目"双季稻区冬季绿色覆盖作物土壤微生态研究"(30671222)
国家"十一五"科技支撑计划项目"农田地表覆盖保护关键技术研究"(2006BAD15B02和2007BAD89B01)
关键词
双季稻
土壤类型
黑麦草
土壤微生物量
覆盖作物
double-rice system, soil type, ryegrass, soil microbial biomass, cover crop
