【摘要】：【目的】研究黃淮海北部地區(qū)犁底層分布現(xiàn)狀及特征。【方法】采用布點(diǎn)取樣方法,根據(jù)黃淮海北部區(qū)土壤質(zhì)地分布圖結(jié)合第二次土壤普查點(diǎn)位選取山東陵縣、河北吳橋縣共108個點(diǎn)位,于2014年冬小麥拔節(jié)期進(jìn)行剖面取樣調(diào)查,測定0—45 cm不同層次土壤水分含量、土壤容重及穿透阻力�！窘Y(jié)果】(1)黃淮海北部地區(qū)耕層平均厚度在14.74 cm,約有76%的被調(diào)研點(diǎn)存在明顯的犁底層,犁底層主要分布在15—30 cm;(2)黃淮海北部區(qū)農(nóng)田剖面各層次土壤容重及穿透阻力存在顯著差異,犁底層容重最大,平均容重在1.54 g·cm~(-3)左右,顯著大于耕層和心土層,在冬小麥拔節(jié)期犁底層穿透阻力為1 371.00—4 256.00 k Pa,顯著大于耕層及心土層穿透阻力;(3)冬小麥整個生育期犁底層穿透阻力均大于2 000 k Pa,阻礙了小麥根系的深扎,造成小麥根系分布淺層化,這在冬小麥生長缺水的地區(qū),易造成作物水分脅迫,同時不利于根系吸收深層養(yǎng)分;(4)土壤穿透阻力土壤與含水量及容重之間有著極顯著相關(guān)關(guān)系,土壤穿透阻力有隨著容重的增加而增加的趨勢,二者之間回歸方程為:y=3 854.09x+3 891.99(y為穿透阻力,x為土壤容重,r=0.84);當(dāng)容重低于1.4 g·cm~(-3)時,土壤穿透阻力均低于2 000 k Pa,穿透阻力不會對作物根系生長產(chǎn)生障礙,而當(dāng)土壤容重在1.4 g·cm~(-3)以上時,穿透阻力對作物的影響同時取決于土壤含水量,穿透阻力隨著土壤水分的增加而降低,對應(yīng)線性回歸方程為:y=-75.93 x+3 153.83(y為穿透阻力,x為土壤質(zhì)量含水量,r=0.82)�！窘Y(jié)論】在現(xiàn)行以旋耕為主的傳統(tǒng)耕作模式下,黃淮海北部地區(qū)農(nóng)田犁底層是普遍存在的,不利于作物根系生長及作物對土壤養(yǎng)分的充分利用,需要適度打破犁底層,構(gòu)建合理耕層結(jié)構(gòu)。
[Abstract]:[objective] to study the present situation and characteristics of plow bottom distribution in the northern part of the Huang-Huai-Hai area. [methods] A sampling method was used to select Shandong Lingxian according to the soil texture distribution map of the northern Huang-Huai-Hai region combined with the site of the second soil Survey. A total of 108 sites in Wuqiao County, Hebei Province, were sampled at jointing stage of winter wheat in 2014 to determine soil moisture content in different layers of 0-45 cm. Soil bulk density and penetration resistance. [results] (1) the average thickness of the topsoil layer in the northern part of the Huang-Huai Sea is 14.74 cm, and about 76% of the investigated sites have obvious plow bottom. (2) there were significant differences in soil bulk density and penetration resistance between different layers of farmland profile in the northern part of the Yellow River and Huaihai Sea, and the average bulk density of plow bottom layer was about 1.54 g cm ~ (-3), which was significantly larger than that of the tilling layer and the core soil layer, and the average bulk density of the plow bottom layer was about 1.54 g cm ~ (-3). At the jointing stage of winter wheat, the penetration resistance of plow bottom layer was 1 371.00-4 256.00 kPA, which was significantly higher than that of plough layer and core soil layer, (3) the penetration resistance of plow bottom layer in whole growing period of winter wheat was more than 2 000 kPa, which hindered the deep root system of wheat. The distribution of wheat roots is shallow, which is easy to cause crop water stress in areas where winter wheat grows and lacks water, and is not conducive to root absorption of deep nutrients. (4) soil penetration resistance soil has a very significant correlation with water content and bulk density. The soil penetration resistance increased with the increase of bulk density, and the regression equation between them was: 1: y 3 854.09 x 3 891.99 (y = 0. 84), and when the bulk density was less than 1. 4 g cm ~ (-3), the regression equation was 0. 4 g / cm ~ (-3). The penetration resistance of soil was less than 2 000 kPA, and the penetration resistance would not hinder the growth of crop root system. However, when the soil bulk density was above 1.4 g cm ~ (-3), the effect of penetration resistance on crop was also dependent on the soil moisture content. The penetration resistance decreased with the increase of soil moisture, and the linear regression equation was: 1: yong-75.93 x 3 153.83 (y = penetration resistance x = 0.82). [conclusion] under the current traditional tillage mode with rotary tillage as the main factor, the penetrability decreased with the increase of soil moisture, and the linear regression equation was: yya-75.93 x 3 153.83 (y = 0.82). The bottom layer of farmland plough in the northern part of Huanghuai Sea is common, which is not conducive to the growth of crop roots and the full utilization of soil nutrients by crops, so it is necessary to appropriately break the bottom layer of plow and construct a reasonable structure of plough layer.
【作者單位】： 中國農(nóng)業(yè)科學(xué)院農(nóng)業(yè)資源與農(nóng)業(yè)區(qū)劃研究所;山東省德州市農(nóng)業(yè)科學(xué)研究院;
【基金】：國家公益性行業(yè)(農(nóng)業(yè))科研專項(xiàng)經(jīng)費(fèi)(201303130)
【分類號】：S151.9
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本文編號：2168260