The following results are obtained:The dry land fertilized N 150 kg hm-2, P 16.4 kg hm-2 and K 62.3 kg hm-2 or fertilized same quantity of NPK combined with pig manure by a nutrient re-utilization of 80% agro-products, with a maize-maize-soybean rotation, irrigated by nature, may accumulates high quantity of mineralized nitrogen in 1m soil before freezing.
The groundwater dynamics and the basic theory of the solute transport aresummarized, and the transport mechanism of LNAPLs in unsaturated soil andthe concept and models of multiphase flow which describe the transportbehaviors of LNAPLs are expatiated.
The nutrient concentrations,microbe and enzyme and their spatial distribution were analyzed for different types in Dongying county of Shandong province in silting coastal area,the main results indicated: ①soil microbes,enzyme and nutrient distribute mainly in 0~20 cm of soil layer,and less in 20~50 cm.
The average bulk density, total porosity, capillary porosity and non-capillary porosity in 0—100 cm soil layer were 1.41 g·cm-3, 52.31%, 46.11% and 6.20% under broadleaved Korean pine forest, and 0.98 g·cm-3, 50.65%, 40.32%, 10.33% under dark coniferous forest, respectively.
An antibiotic producing strain Streptomyces violaceusniger was isolated from soil sample, characterized and studied for antibacterial and antifungal activity profile.
These points can be estimated by introducing the soil factor (Ks) and tree species factor (Kt) to potential evapotranspiration with the Penman formula.
Root biomass, length, and the number of roots in every diameter class, for each soil layer and for each plant species, are regarded as observation variables.
The results show that most of the vertical distributions of plant roots belong to the type wherein the roots are concentrated in the topsoil layer (0-20 cm), far more than those in the lower soil layers.
Ecological Benefit of Reforestation in a Severely Degraded Red Soil Region