本文選題：免耕　切入點(diǎn)：秸稈覆蓋　出處：《中國(guó)農(nóng)業(yè)科學(xué)》2017年24期

【摘要】：【目的】探討免耕及秸稈覆蓋等保護(hù)性耕作措施對(duì)旱作農(nóng)田干濕交替過(guò)程中土壤呼吸速率的影響�！痉椒ā炕谠O(shè)在隴東黃土高原的長(zhǎng)期草田輪作定位試驗(yàn),試驗(yàn)開(kāi)始于2001年,包括傳統(tǒng)耕作(T,翻耕并移除秸稈)、耕作覆蓋(TS,翻耕之后覆蓋秸稈)、免耕移除秸稈(NT,不翻耕但除去秸稈)和免耕(NTS,不翻耕且保留秸稈)4個(gè)處理。2014年7—8月干濕交替階段季采用LI-8150多通道土壤碳通量測(cè)量系統(tǒng)對(duì)農(nóng)田土壤呼吸速率、土壤溫度和含水量進(jìn)行連續(xù)原位測(cè)定�！窘Y(jié)果】T、TS、NT和NTS處理干旱階段的平均土壤呼吸速率分別為2.16、3.56、2.26和2.45μmol·m~(-2)·s~(-1),濕潤(rùn)階段分別為2.09、5.31、2.80和3.56μmol·m~(-2)·s~(-1)。降雨初期秸稈覆蓋處理(TS和NTS)土壤呼吸速率動(dòng)態(tài)變化與無(wú)秸稈覆蓋處理(NT和T)具有顯著差異。干濕交替過(guò)程中,干旱階段土壤呼吸速率與土壤溫度(19.1—28.2℃)呈負(fù)相關(guān)、與土壤含水量呈正相關(guān)關(guān)系;濕潤(rùn)階段則相反,且土壤含水量對(duì)土壤呼吸速率的解釋程度降低。土壤呼吸速率在濕潤(rùn)階段日動(dòng)態(tài)波動(dòng)較大,其溫度敏感性(Q10)在T、TS、NT和NTS處理下分別為1.37、1.24、1.31和1.25;干旱階段土壤呼吸速率日動(dòng)態(tài)平緩,Q10值低于1.0�！窘Y(jié)論】長(zhǎng)期保護(hù)性耕作提高了農(nóng)田的土壤呼吸速率,且秸稈覆蓋處理比免耕措施提高土壤呼吸速率的效應(yīng)更加顯著。秸稈覆蓋能夠有效平抑土壤水分和溫度的變化,提高土壤呼吸速率,降低土壤呼吸的溫度敏感性。論文明確了干濕條件下旱作農(nóng)田土壤呼吸動(dòng)態(tài)及其影響因素,對(duì)準(zhǔn)確量化旱作農(nóng)田碳通量具有積極意義。
[Abstract]:[objective] to investigate the effect of conservation tillage measures such as no-tillage and straw mulch on soil respiration rate during dry-wet rotation in dry-wet field. [methods] based on the long-term rotation experiment in Loess Plateau of East Gansu Province, the experiment began in 2001. These treatments include traditional tillage, tillage and removal of straw stalks, tillage mulching with TSs, mulch after tillage, no tillage removal of straw NTs, no tillage but removal of straw) and no tillage NTS, no tillage and retention of straw). LI-8150 multi-channel soil carbon flux measurement system was used to measure soil respiration rate. The soil temperature and water content were measured in situ continuously. [results] the average soil respiration rates of Tetsmont and NTS treatments in drought stage were 2.16 ~ 3.56 ~ 2.26 and 2.45 渭 mol / m ~ (-1) ~ (-1) ~ (-1), respectively, and those in wet stage were 2.09 ~ 5.31 ~ 2.80 and 3.56 渭 mol / m ~ (-2) 路s ~ (-1) 路s ~ (-1), respectively. TS and NTS were treated by straw mulching in the early stage of rainfall. There was significant difference between the dynamic change of rate and the treatment of NT and T without straw mulch. Soil respiration rate was negatively correlated with soil temperature (19.1-28.2 鈩，

本文編號(hào)：1677296