發(fā)布時間：2018-05-17 15:03

  本文選題：地膜覆蓋 + 秸稈還田��； 參考：《蘭州大學》2017年碩士論文

【摘要】：地膜雙壟溝播技術已成為半干旱半濕潤黃土高原雨養(yǎng)農業(yè)區(qū)被大面積推廣用于作物增產的種植模式,其具有覆蓋抑蒸、壟溝播種、集雨保溫等優(yōu)點。玉米秸稈富含有機物質,其能作為輸入土壤的再生生物資源幫助作物生長。然而由于黃土高原地區(qū)水溫條件不適宜和降雨稀少等原因腐解玉米秸稈所需時間較長,因此我們把地膜雙壟溝播技術與秸稈還田有機結合起來集兩者之長處,找到了一種既能提高土壤肥力又能增加作物產量的種植模式。但在該種植模式下是否會影響土壤理化性狀,土壤理化性狀和作物產量的增加不能以犧牲土壤理化性狀為前提。土壤團聚體、pH值、容重等均是評估土壤理化性狀重要指標。本實驗于2015年分別在甘肅省會寧縣和榆中縣進行,實驗設置四個處理:對照(CK)、秸稈還田(S)、覆膜(M)、秸稈還田+覆膜(SM),分別重復三次,隨機區(qū)組排列。于2015年7月及收獲時采樣,測定指標有pH、全氮、礦化氮、土壤團聚體水穩(wěn)性、MWD、耕層土壤含水量、微生物碳氮、有機碳、容重和玉米生物量。主要得出了以下結果:(1)地膜覆蓋在籽粒產量和根生物量上增產效果顯著。會寧實驗地較不覆膜處理在籽粒產量和根生物量上增產幅度分別為83%和34%,榆中實驗地增產幅度分別為140%-38%。秸稈還田對其無顯著影響。(2)秸稈還田能顯著影響全氮含量,較不秸稈還田處理而言增加幅度為18-30%;能顯著影響有機碳含量,增加幅度為12-40%;能顯著影響微生物量碳、氮含量,增加幅度分別為42-117%、16-102%;能顯著影響土壤容重,減少幅度為4-9%。(3)地膜覆蓋能顯著影響硝態(tài)氮含量,較不覆膜處理而言增加幅度為73-325%;能顯著影響土壤pH,減少幅度為0.19-0.35;能顯著影響土壤容重,增加幅度為6-7%。。pH值與硝態(tài)氮含量存在強相關性。(4)秸稈還田能顯著增加土壤大團聚體(0.25 mm)比重,較不秸稈還田處理而言增加幅度為10-37%;地膜覆蓋能顯著增加土壤大團聚體(0.25 mm)比重,較不覆膜處理增加幅度為8-34%。秸稈還田對平均質量直徑(MWD)影響不顯著,地膜覆蓋影響顯著,秸稈還田與地膜覆蓋對其有交互作用。在覆膜前提下不秸稈還田處理MWD增加幅度較秸稈處理MWD增加幅度更大,在秸稈還田前提下不覆膜較對照(CK)MWD顯著增加,而覆膜(M)與秸稈還田+覆膜(SM)之間差異較小或不存在顯著性。通過上述實驗我們得出秸稈還田與地膜覆蓋均能顯著增加土壤大團聚體(0.25 mm)比重,土壤大團聚體的增加有利于土壤孔隙性良好,土質疏松、耕性良好,土溫協調穩(wěn)定,保肥供肥性能強等,而秸稈還田與地膜覆蓋均能顯著增加土壤大團聚體比重可能是與根生物量及微生物活性增加有關;地膜覆蓋顯著減小pH,可能破壞土壤理化性狀,影響微生物及農田作物的生長發(fā)育等,pH減小與土壤中硝態(tài)氮的富集有關;地膜覆蓋會增加土壤容重即土壤致密性增加,可會直接或間接影響作為生長發(fā)育。秸稈還田與地膜覆蓋的耕作模式會部分影響土壤理化性狀,在進行耕作時可以農田覆膜可以隔年實施一次,有利于土壤理化性狀的恢復。
[Abstract]:The double ridge furrow sowing technology has been widely used in the semi arid and semi humid loess plateau in the rain raising agricultural area, which has been widely used to increase the yield of crops. It has the advantages of covering the steaming, furrow sowing, and collecting rain and heat preservation. The corn straw is rich in organic matter, which can be used as the regenerated biological resources of the soil to help the crop growth. It takes a long time to decompose corn straw for the reasons that the water temperature is not suitable and the rainfall is scarce in the plateau. Therefore, we combine the double ridge furrow seeding technique with the straw to the field, and find a planting pattern which can increase the soil fertility and increase the crop yield. Soil physical and chemical properties, soil physical and chemical properties and increase of crop yield can not be taken as the premise of sacrificing soil physical and chemical properties. Soil aggregate, pH value and bulk density are all important indexes for evaluating soil physical and chemical properties. The experiment was carried out in Huining county and Yuzhong County of Gansu Province in 2015 respectively. The experiment set up four treatments: control (CK), straw return Field (S), film mulching (M), straw returning and film mulching (SM) were repeated three times in random area. In July 2015 and harvest time, samples were sampled, and the indexes were pH, total nitrogen, mineralized nitrogen, soil aggregate water stability, MWD, soil water content, microbial carbon and nitrogen, organic carbon, bulk density and corn biomass. The main results were as follows: (1) mulched in the seed film The effect of grain yield and root biomass on yield increased significantly. The yield increased by 83% and 34% on Grain Yield and root biomass in the experimental area of Huining, and there was no significant effect on the increase of yield in Yuzhong. (2) the total nitrogen content could be significantly affected by straw returning. The addition of 18-30% can significantly influence the content of organic carbon and increase the range of 12-40%, which can significantly affect the amount of carbon and nitrogen of microorganism, and the increase of nitrogen content is 42-117%, 16-102%, which can significantly affect the soil bulk density, and the decrease range is 4-9%. (3) film mulching can significantly affect the nitrate nitrogen content, and the increase is 73-325% compared with the non plastic film treatment. The effect of soil pH was reduced to 0.19-0.35, which could significantly affect soil bulk density, the increase of 6-7%..PH value was strongly correlated with nitrate nitrogen content. (4) straw returning could significantly increase the proportion of soil large aggregate (0.25 mm), compared with no straw returning treatment, the increase was 10-37%, and film mulching could significantly increase soil aggregate (0.2 The proportion of 5 mm) was not significantly increased by 8-34%. straw returning to the average mass diameter (MWD), and the effect of Mulching on the mulching was significant. The mulching film (CK) MWD increased significantly, while the difference between the mulching (M) and the straw mulching (SM) was small or not significant. Through the above experiments, we concluded that the proportion of soil large aggregates (0.25 mm) could be significantly increased by the straw returning and mulching, and the increase of large soil aggregates was beneficial to soil porosity, soil porosity and tillage. Well, the soil temperature is coordinated and stable, and the performance of fertilizer and fertilizer is strong, while the proportion of straw returning and film mulching can significantly increase the proportion of soil large aggregate, and the soil mass and microbial activity may be increased. The film mulching can significantly decrease pH, may destroy soil physical and chemical properties, affect the growth and development of microorganism and crop, and pH decrease with soil. The enrichment of soil bulk density, that is, the increase of soil bulk density, that is, the increase of soil density, which can directly or indirectly affect the growth and development. The tillage pattern of straw returning and mulching will affect the physical and chemical properties of soil partly. Recovery.
【學位授予單位】：蘭州大學
【學位級別】：碩士
【學位授予年份】：2017
【分類號】：S316;S141.4

【相似文獻】

相關博士學位論文 前2條

1 余超然;麥棉兩熟周年秸稈還田對棉花產量品質形成的影響及其生理機制[D];南京農業(yè)大學;2016年

2 張秀梅;高茬秸稈還田旋耕機工作機理與試驗研究[D];華中農業(yè)大學;2017年

相關碩士學位論文 前1條

1 呂潔婷;秸稈還田與地膜覆蓋對土壤理化性狀影響[D];蘭州大學;2017年

，

本文編號：1901841