草业科学
草業科學
초업과학
PRATACULTURAL SCIENCE
2010年
4期
40-45
,共6页
孔玉华%姚风军%鹏爽%刘艳%董文轩%白龙
孔玉華%姚風軍%鵬爽%劉豔%董文軒%白龍
공옥화%요풍군%붕상%류염%동문헌%백룡
围封%放牧%草地%土壤碳密度%土壤碳汇/源转换
圍封%放牧%草地%土壤碳密度%土壤碳彙/源轉換
위봉%방목%초지%토양탄밀도%토양탄회/원전환
fence%grazing%grassland%soil organic carbon density%soil carbon sink and source conversion
土地利用变化是影响土壤碳储量的主要人为因素,准确掌握不同利用方式下土壤碳积累及汇/源功能转换特征,对预测土壤碳释放量趋势有着很重要的意义.为明确不同利用方式下草地土壤碳储量及碳汇/源功能的动态变化特征,以位于科尔沁沙地东南围封草地与放牧地为研究对象,采用有机碳密度法分析了0~30 cm土层有机碳储量及其在5-11月的变化规律.结果表明:围封草地土壤有机碳含量随着土层的加深呈递减的变化,放牧地土壤有机碳含量随着土层的加深不同土层间无显著差异.5-11月围封草地0~30 cm土层土壤有机碳密度变化为2.8~4.0 kg/m~2,变幅为1.2 kg/m~2.5-9月放牧地0~30 cm土层土壤有机碳密度变化为3.4~4.7 kg/m~2,变幅为1.3 kg/m~2.围封草地在5-8月为土壤碳源过程,8-9月为土壤碳汇过程,9-11月为土壤碳源过程.放牧地土壤碳库较稳定,无明显的碳汇/源的变化过程.合理的放牧利用有助于土壤碳的积累,减少碳释放.
土地利用變化是影響土壤碳儲量的主要人為因素,準確掌握不同利用方式下土壤碳積纍及彙/源功能轉換特徵,對預測土壤碳釋放量趨勢有著很重要的意義.為明確不同利用方式下草地土壤碳儲量及碳彙/源功能的動態變化特徵,以位于科爾沁沙地東南圍封草地與放牧地為研究對象,採用有機碳密度法分析瞭0~30 cm土層有機碳儲量及其在5-11月的變化規律.結果錶明:圍封草地土壤有機碳含量隨著土層的加深呈遞減的變化,放牧地土壤有機碳含量隨著土層的加深不同土層間無顯著差異.5-11月圍封草地0~30 cm土層土壤有機碳密度變化為2.8~4.0 kg/m~2,變幅為1.2 kg/m~2.5-9月放牧地0~30 cm土層土壤有機碳密度變化為3.4~4.7 kg/m~2,變幅為1.3 kg/m~2.圍封草地在5-8月為土壤碳源過程,8-9月為土壤碳彙過程,9-11月為土壤碳源過程.放牧地土壤碳庫較穩定,無明顯的碳彙/源的變化過程.閤理的放牧利用有助于土壤碳的積纍,減少碳釋放.
토지이용변화시영향토양탄저량적주요인위인소,준학장악불동이용방식하토양탄적루급회/원공능전환특정,대예측토양탄석방량추세유착흔중요적의의.위명학불동이용방식하초지토양탄저량급탄회/원공능적동태변화특정,이위우과이심사지동남위봉초지여방목지위연구대상,채용유궤탄밀도법분석료0~30 cm토층유궤탄저량급기재5-11월적변화규률.결과표명:위봉초지토양유궤탄함량수착토층적가심정체감적변화,방목지토양유궤탄함량수착토층적가심불동토층간무현저차이.5-11월위봉초지0~30 cm토층토양유궤탄밀도변화위2.8~4.0 kg/m~2,변폭위1.2 kg/m~2.5-9월방목지0~30 cm토층토양유궤탄밀도변화위3.4~4.7 kg/m~2,변폭위1.3 kg/m~2.위봉초지재5-8월위토양탄원과정,8-9월위토양탄회과정,9-11월위토양탄원과정.방목지토양탄고교은정,무명현적탄회/원적변화과정.합리적방목이용유조우토양탄적적루,감소탄석방.
Land-use change is the main affecting factor of soil carbon storage. It is very important to predict the trend of soil carbon release under different land-use patterns so that the soil carbon accumulation and conversion of soil carbon sink and source could be better understand. The organic carbon density and variation patterns of organic carbon storage within 0 to 30 cm soil layer of fenced grassland and grazing land in the southeast of Horqin sandy land were studied from May to November. The results showed that the soil organic carbon content of enclosed grassland decreased significantly with the soil depth, but not for the grazing land. Soil organic carbon density of the fenced grassland within 0 to 30 cm soil layer varied from 2.8 kg/m~2 to 4.0 kg/m~2. And it was from 3.4 kg/m~2 to 4.7 kg/m~2 for the grazing land. In general, it was the carbon source process from May to August and from September to November, and it was the carbon sink process from August to September for the fenced land. However, soil carbon storage of the grazing land was more stable, the conversion process of soil carbon sink and source was no significant. It suggested that the reasonable grazing utilization contributed to accumulation of soil carbon and could reduce carbon emission.