土壤构造对毛细管水上升影响的研究

研究土壤构造对毛细管水上升的影响及变化规律。通过观测并分析不同构造的土壤其毛细管水上升速度和高度,成层性构造土壤,当下部土壤层厚度小于该层毛细管水上升最大高度,毛细管水上升的最终高度取决于上部土壤层的性质;上部土壤层颗粒愈细,含水量愈大,毛细管水上升速度越慢,若上部绝对隔水,毛细管水不上升。     

赣州峰山国家森林公园森林碳汇储量评估初报

为促进赣州森林碳汇市场化的建立,对赣州峰山国家森林公园进行森林碳储量估值并核算其碳汇价值,经核算,峰山森林公园森林植被层碳储量523175.74t,枯落物层碳储量53703.47t,土壤层碳储量199569.02t,累计森林碳汇总储量77.64万t,评估碳汇价值为2.12亿元。     

Exploring soil layers and water tables with ground-penetrating radar

Ground-penetrating radar (GPR) has been used predominantly for environments with low electrical conductivity like freshwater aquifers, glaciers, or dry sandy soils. The objective of the present study was to explore its application for mapping in subsurface agricultural soils to a depth of several meters. For a loamy sand and a clayey site on the North China Plain, clay inclusions in the sand were detected; the thickness, inclination, and continuity of the confining clay and silt layers was assessed; and a local water table was mapped. Direct sampling (soil coring and profiling) in the top meter and independent measurement of the water table were utilized to confirm the findings. Also, effective estimates of the dielectric number for the site with the dielectric number of moist clayey soils depending strongly on frequency were obtained. Thus, important properties of soils, like the arrangement and type of layers and in particular their continuity and inclination, could be explored with moderate efforts for rather large areas to help find optimal locations for the time-consuming and expensive measurements which would be necessary to detail a model of the subsurface.     

华北山石区落桦混交林枯落物与土壤层持水能力研究

为了更好地监测和评价森林持水能力,对华北山石区落桦混交林的枯落物层与土壤层持水能力进行研究。结果表明:落桦混交林中枯落物生物量、最大持水量、最大持水率、吸水速率和有效拦蓄量都是半分解层大于未分解层,其中半分解层的最大持水量是未分解层的1.36倍,半分解层的最大持水率为未分解层的1.1倍,半分解层的有效拦蓄量是未分解层的1.36倍。落桦混交林的土壤层持水能力为290.3t·hm~(-2),其土壤的初渗速率为23.6 mm·min~(-1),稳渗速率为3.3 mm·min~(-1),土壤渗透性与入渗时间的拟合方程为f=26.666t~(-1.036),相关系数为0.970。