黑核桃根系分布特征研究

摘要

[目的]研究黑核桃根系在土壤中的分布特征,为黑核桃的水肥高效管理提供理论依据.[方法]以5a生黑核桃为试材,采用剖面挖掘和分层取样法,利用植物图像分析系统和烘干称重法,分析不同土层的根系生物量密度、根系表面积密度和总根长密度.[结果]根系生物量密度、根系表面积密度和总根长密度在垂直和水平方向均呈现递减的趋势.在垂直分布上,根系垂直最深分布达到150 cm土层,0～70 cm土层是根系垂直分布的主要区域,该区域内根系生物量占垂直分布总量的85.45% .根系表面积密度最大值和总根长密度均出现在0～10 cm土层,分别为17.66 mm2/cm3和0.34 cm/cm3;在水平方向上,水平分布最远分布达到120 cm以上,距离树干0～80 cm是根系生物量水平分布的主要区域,该区域内根系生物量占水平分布总量的93.98% .根系表面积密度和根长密度最大值均在距离树干0～20 cm的区域,分别为0.12和0.43 cm/cm3.[结论]5 a生黑核桃根系垂直最深分布达到150 cm土层,水平分布最远分布达到120 cm以上.距树干0～80 cm,深0～70 cm的区域是黑核桃根系分布的主要区域,该土层应该作为肥水管理的重点区域.%[Objective] To explore the distribution characteristics of black walnut root in soil, and pro-vide a theoretical basis for the efficient management of the water and fertilizer.[Method]5a black walnut was used as a test material, the biomass density, root surface area density and total root length of root system in different soil layers were analyzed by means of soil excavation and stratified sampling and the plant image anal-ysis system and the drying weighing method.[Result]The root biomass density, root surface area density and total root length density showed a decreasing trend in the vertical and horizontal direction. In the vertical dis-tribution, the deepest vertical distribution of the root system reached the soil layer of 150 cm. 0-70 cm layer area was the main one of the vertical distribution of root, the root system biomass accounted for 85. 45% of the total vertical distribution. The maximum value of root surface area density and total root length density were distributed in the soil layer of 0-10 cm, which were 17. 66 mm2/cm3 and 0. 34 cm/cm3, respectively. In the horizontal direction, the farthest distribution of the horizontal distribution was above 120 cm, the distance be-tween the tree trunk and 0-80 cm was the main area of the distribution of root biomass. The root biomass ac-counted for 93. 98% of the total level of distribution. The maximum root surface area density and root length density were distributed in the soil layer 0-20 cm from the tree trunk, which were 0. 12 cm/cm3 and 0. 43 cm/cm3, respectively.[Conclusion]5 years old black walnut root system vertical deepest distribution reached 150 cm soil layer, horizontal distribution of the farthest distribution reached 120 cm. The root distribution of black walnut was mainly located in the area of 0-80 cm from the trunk, and the area of 70 cm deep is the main area of root distribution of black walnut, and the soil layer should be the key area of fertilizer and water management 70 cm deep. This soil layer should be regarded as the key area for the management of fertilizer and water.