本文選題：黃土區(qū) + 刺槐林地��； 參考：《水土保持學(xué)報(bào)》2017年03期

【摘要】：為了研究黃土區(qū)人工林地土壤水分特征曲線及土壤水勢(shì)特征,以陜北黃土區(qū)人工刺槐林地為研究對(duì)象,利用中子水分儀和中國(guó)科學(xué)院地理科學(xué)與資源研究所設(shè)計(jì)的負(fù)壓計(jì),對(duì)其2015年4月1日—2015年10月31日0—200cm土層的土壤含水量和土壤水勢(shì)進(jìn)行了連續(xù)觀測(cè),并運(yùn)用灰關(guān)聯(lián)法分析了表層(0—40cm)、中層(50—120cm)、深層(130—200cm)及4—10月土壤水勢(shì)灰關(guān)聯(lián)度。結(jié)果表明:(1)陜北黃土區(qū)人工刺槐林地各土層土壤水分特征曲線可用Gardner模型冪函數(shù)方程θ=aS-b進(jìn)行擬合,擬合參數(shù)a值大小為表層土壤(0.103 8)中層土壤(0.094 4)深層土壤(0.086 0);b值大小為表層土壤(0.284)中層土壤(0.291)深層土壤(0.298)。(2)通過(guò)土壤水分特征曲線求得人工刺槐林地土壤水分常數(shù),田間持水量和凋萎系數(shù)的平均值分別為25.53%和8.42%,最大有效水范圍平均達(dá)17.11%。通常用土壤水吸力為0.1 MPa時(shí),比水容量值來(lái)表征土壤供水能力,人工刺槐林地該值的大小表現(xiàn)為表層土壤(56.73%)中層土壤(53.74%)深層土壤(50.84%)。(3)人工刺槐林地土壤水勢(shì)垂直空間分布表現(xiàn)為表層土壤水勢(shì)從-0.21 MPa逐層增加到-0.08 MPa,中層土壤水勢(shì)動(dòng)態(tài)波動(dòng)較大,整體呈下降趨勢(shì),深層土壤水勢(shì)穩(wěn)定在-1.14 MPa附近。灰關(guān)聯(lián)度分析得出R12(0.899 8)R23(0.711 5)R13(0.702 8),人工刺槐林地土壤水勢(shì)表層與中層關(guān)系較為密切,深層與中層關(guān)系次之,表層與深層關(guān)系最差。(4)人工刺槐林地0—200cm土層土壤水勢(shì),4—6月呈下降趨勢(shì),7—8月顯著上升,9—10月再次下降。從各月土壤水勢(shì)灰關(guān)聯(lián)度來(lái)看,R_(10)(0.868 9)R_(05)(0.806 7)R_(09)(0.780 4)R_(07)(0.676 3)R_(06)(0.654 8)R_(08)(0.611 4),人工刺槐林地土壤水勢(shì)10月,5月,9月變化態(tài)勢(shì)與4月關(guān)聯(lián)度較高;土壤水勢(shì)7月,6月,8月與4月關(guān)聯(lián)度較差。
[Abstract]:In order to study soil water characteristic curve and soil water potential characteristics of artificial forest land in loess region, the artificial Robinia pseudoacacia forest land in North Shaanxi Province was studied. The negative pressure meter was designed by neutron moisture meter and Institute of Geography and Resources of Chinese Academy of Sciences.The soil moisture content and soil water potential of 0-200cm soil layer from April 1, 2015 to October 31, 2015 were continuously observed.The grey correlation degree of soil water potential between April and October was analyzed by using grey correlation method in surface layer (0-40 cm), middle layer (50-120 cm) and deep layer (130-200 cm).The results showed that the soil moisture characteristic curves of artificial Robinia pseudoacacia forest in North Shaanxi could be fitted by the power function equation 胃 (aS-b) of Gardner model.The fitting parameter a value is surface soil (0.1038)) middle soil (0.094 4)) deep layer soil (0. 2884) middle soil (0. 291)) deep layer soil (0. 298N. 2) soil moisture constant of artificial Robinia pseudoacacia forest is obtained by soil water characteristic curve.The average values of field water holding capacity and wilting coefficient were 25.53% and 8.42%, respectively, and the maximum effective water range was 17.11%.When the soil water suction is 0. 1 MPa, the specific water capacity is used to characterize the soil water supply capacity.The value of soil water potential in artificial Robinia pseudoacacia forest was 56.73) (53.74)) the vertical spatial distribution of soil water potential of artificial Robinia pseudoacacia forest showed that the surface soil water potential increased from -0.21 MPa to -0.08 MPa, and the dynamic fluctuation of soil water potential in middle layer was larger than that in artificial Robinia pseudoacacia forest, and the soil water potential of artificial Robinia pseudoacacia forest was increased from -0.21 MPa to -0.08 MPa.The water potential of deep soil was stable at -1.14 MPa.Grey correlation analysis showed that R12C 0.899 8)R23(0.711 5)R13(0.702 8, soil water potential in artificial Robinia pseudoacacia forest had a close relationship with the middle layer, followed by deep layer and middle layer.Soil water potential of 0-200cm soil layer in artificial Robinia pseudoacacia forest showed a downward trend in April-June and increased significantly in July-August and decreased again in September-October.According to the grey correlation degree of soil water potential in each month, 0.868 9)R_(05)(0.806 7)R_(09)(0.780 4)R_(07)(0.676 3)R_(06)(0.654 8)R_(08)(0.611 4C was observed. The variation of soil water potential in October, May and September in artificial Robinia pseudoacacia forest was higher than that in April, and the correlation degree of soil water potential in July, June, August and April was poor.
【作者單位】： 北京林業(yè)大學(xué)水土保持學(xué)院;
【基金】：國(guó)家林業(yè)局公益性行業(yè)科研專項(xiàng)經(jīng)費(fèi)項(xiàng)目“南方退耕還林工程建設(shè)效益監(jiān)測(cè)評(píng)價(jià)研究”(201004018)
【分類號(hào)】：S714
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本文編號(hào)：1762266