發(fā)布時(shí)間：2018-07-01 07:50

  本文選題：施氮量 + 根茬碳分解�。� 參考：《西北農(nóng)業(yè)學(xué)報(bào)》2017年10期

【摘要】：通過(guò)田間埋藏分解試驗(yàn),比較3種施氮量(0、120和240kg·hm~(-2))處理的玉米根茬分別與土婁土和黑壚土混合后,在土壤中分解1a期間根茬碳分解差異,并利用碳穩(wěn)定同位素δ~(13) C方法,研究根茬碳分解對(duì)土壤有機(jī)碳的貢獻(xiàn)。結(jié)果顯示:楊凌地區(qū)水熱條件較好,試驗(yàn)期間降水量總和較長(zhǎng)武高215mm;楊凌試驗(yàn)地15cm和45cm土層平均溫度分別較長(zhǎng)武高3.2℃和4.2℃。分解1a后,黑壚土中根茬殘留碳量較土婁土中高20.9%~43.6%。根茬來(lái)源的土壤有機(jī)碳比例在土婁土、黑壚土中分別為22.4%~44.7%和27.4%~38.3%。在黑壚土中,玉米根茬分解1a后,根茬來(lái)源的土壤有機(jī)碳質(zhì)量分?jǐn)?shù)顯著高于在土婁土中,而在3種不同施氮量處理的玉米根茬之間,根茬來(lái)源的土壤有機(jī)碳質(zhì)量分?jǐn)?shù)差異不顯著。研究表明,水熱條件相對(duì)較好的土壤環(huán)境能夠促進(jìn)玉米根茬殘?bào)w的分解礦化,而土壤深度、質(zhì)地、施肥狀況等會(huì)影響有機(jī)殘?bào)w還田腐解與土壤有機(jī)碳的更新。
[Abstract]:Field burial decomposition experiments were conducted to compare the difference of root carbon decomposition between three treatments (0120 and 240kg hm ~ (-2) after mixing with low soil and black loessial soil, respectively, and using the stable isotope 未 ~ (13) C method. The contribution of stubble carbon decomposition to soil organic carbon was studied. The results show that the water and thermal conditions in Yang Ling area are better, the summation of precipitation during the test period is 215mm higher than that of Changwu, and the average soil temperature of 15cm and 45cm is 3.2 鈩，

本文編號(hào)：2087072