Abstract:A reginal soil information system (RSIS) is developed on IBM-PC-XT microcomputer using FORIRAH and DBASE-IV as the supporting software RSIS has three levels of menu to execute its all functions based on the communication between FORTARAH and DBASE-IV. The main functions ate as follows: 1. Creation of RSIS data base; 2. Creation of distal terrain model (DTM); 3. Soil data base management; 4. Statistics; 5. Charting and reporting; 6. Selection analysis and conbiration of information and 7. Soil and non-soil information complex. and evaluation. The tested results of the system in Nongan County of Jilin Province showed: that the results were satified.

Abstract:Throughout the world, especially in developing countrtes land resouree managers are constrained in their planning and decision rn}king because of a critical lack of information about their soil and terrain resources. In cases where scientific data does exist, its effeetive exchange and transfer is also constrained by lack of standardization in describing and recording important resource information, so it is favouralble for decision-makers and policy-makers to improve mapping and monitoring of world soils and terrain resources and develop an information system of delivery of accurate, useful, and timely information about soils&terrain resourees. Also, the standardization of information is conviene for its delivery and exchange.

Abstract:In order to study the chemistry of leacheate ,and soils under coniferous forest, the samples of precipitation, throughfall and soil leacheate under coniferous forest on the northern slope of the Changbai Mountain were collected and analysed The sample plot studied is situated in the natural reserve on the northern slope of the Changbai Mountains Antu County, Jilin Province, being 1100-1700 m above sea level and a basult plateau covered with volcanic ash and sand in the surface. The mean annual.

Abstract:Changes of iron and manganese of soil in different deswamping stages including the changes of Si0₂/Fe₂O₃ and TiO₂/MnO molecular ratios as well as free and active iron in the soil and different fractions, i.e.,<0.002 mm, 0.002-0.005 mm, 0.005-0.01 mm, and 0.01-0.05 mm were studied comparatively. The distribution of iron and manganese in soil profile was also studied. to addition, the reducing capability of soil was also studied through submerged incubation in Laboratory. The two experimental catenas which consisted of sdvamp soil, gleyed paddy soil and periodically submergic paddy sail were collected from wetiands in Idubei and Jiangsu Provinces tespectively. The gleyed paddy soil and, periodically submergic paddy soil were derived from swamp soil. The gleyed paddy soil which was of a higher content of organic matter in gleyed horizon was found in the initial stage of soil deswamping, but the periodically submergic paddy soil with a lower content of organic matter in gleyed horizon was in the late stage of soil deswamnine.

Abstract:The Freundlich adsorption eqmtion (x=kc^1/0)was developed based on the interaction between solute (or adsorbate), solven and adsorbent surface. x is the adsorption capacity, C the concentrarion of equilibrium solition, and k the characteristic parameter, as a measurement of the capacity of adsorption, which is pr oportional to the equilibrium constant of Zn adsorption. α is related to the ratio of the solvent moleculae released from solute and adsorben surface and could be considered as a measurement of the intensity of adsorption force. The welues of k and α calculated were used satisfactorily to explain the mechanism and movement of Zn added in calcareous soil.

Abstract:In accordance with the calculation of water balance equation, the amounts of water consumed in a rainfed wheat field in three experimental seasons were 435.5, 326.0 and 293.8 mm respectively. These results can represent the water consumption under the hydcological condition in excessive, moderate and defective levels respectively in this region. The biomass yield (grain-J-straw) of the wheat was proportional to the water consumption. To take the biomass of the first experimental season a,s the index of 100, the biomass yields of the second and of the third were 85 and 70 respectively. But the response of the grain yield was not identical to the that of tht biomass. They were 100, 102 and 70 respectively in which the highest one was found in the second experimental season. Because the amount of water consumed in this season was relatively low that the water use efficiency was very high (1.73×10^-3kg/l) which was excellent in North China. About 50%; of the total amount of water consumed came froth the water stored in soil before sowing. In the year less in rain fall during the growing season but abundant in water stored in soil, this percentage would be up to 60% showing that soil water is an important water source for wheat growth. lJnder optimum fertilizing conditions, the water use efficiency of wheat was more than 1.26×10^-3kg/1 which was an important parameter for the development of empirical model used to predict wheat yield.

Abstract:The present paper deals with the change in organic matter and its role in aggregarion in uhe semiarid ridge culture and rotation of paddy rice and upland crops under different fertilization conditions. The results indicated that the contents of organic carbon in soil, carbon in heavy fraction, loosely combined humus and stably combined humus were obviously increased，when the pig manure was applied. The amounts of organic carbon, loosely combined humus and stably combined humus in soil were decreased gradually as time went on. On the contrary, the carbon in heavy fraction, tike quantity of complexation and the degree of complexation were raised. The semiarid ridge culture was beneficial to the accumulation of organic carbun, carbon in heavy fraction and loosely combined humus. The loosely combined humus and stably comtined humus were beneficial to the formation and stabilization of > 0.25mm aggrebates. The tightly combined humus was iimpottant for the stabilization of microaggregation.

Abstract:The water-retention characterstics, saturated hydraulic conductivity and water evapoiation of three orange-orchard red soils in centaal Zhejiang, Chiua, and the effect of soil conditioners on aggregation and evaporation of the soils were studied under laboratory conditions. The resups showed that the water-retention capacity of the soils was positively correlated with <0.01mm physical clay content (r=0.933^**), and the saturated hydraulic conductivity of the soils was very highly correlated with mean weight-diameter (MWD) (r=0.956^**) and the destruction percentage of soil aggregates (r=-0.996^**). When soil suction ranged from 50 to 100 kPa, irrigation would beweeded for citrus. Application of soil conditioners increased >0.25mm waterstable aggregates and MWD, and the order of the effectiveness was polyvinyl alcohol (PVA)>polyproyreneamide (PAM)> hydrolytic polyacrylonitrile (HPAN). The sequence of reduction of average daily evaporation due to application of soil conditionerwas quaternary yellow clay>purple sandstone soil>red sandstone soil.

Abstract:In this paper various compounds of phosphorus(P) in soils were fractionized pinto H₂0-P,Al-P,Fe-P,Ca-lP，Occluded P(O-P)，labile organic P(LO-P)，moderate labile organic P(MLO-P), moderate resistant organic P(MRO-P) and High Resistant organic P(HRO-P). Available P in soils and up-taken P in lolants were determined. The interaction effect among fractions of P and the relative availibility of these P fraction were discussed in terms of path analysis. The results are showed as follows.

Abstract:Influences of six organic pollutants (styrene, m-dichlorobenzene, o-Dichlorobenzene, Chllotobenzene, Dibutyl phthalate, and Hexadecane) on pure culteureced Azotobdcter claroococrzm and Cellzrlomonas sp., as well as on actinomycetes, molds and yeasts in the soil were studied. These microbes were collected, isolated and identified by the authors from the upland soils irrigated with the water from the Datong river in Chang}zhou region of Jiangsu province. The experiment data were processed by the means of variance analysis in order to get rid of the disturbance of the experimental errors and make more reliable analysis. The results ahowed that these pollutants had different effects on different microbes at concentrations of both lOppm and 50ppm: they either decrease the counts of Azorobacter clarococczzm, Cellzzlomonas sp. and actinomycetes or increase the counts of molds and yeasts, otherwise they had no significant effect on soil microbes. Among these effects Cellzzlomoszas sp. could not be alive after dibutyl phthalate treatment at concentrations of 10 ppm and 50 ppm.

Abstract:According to the experiment condacted by combining the extracr}n method reported in recent years for measuring soil microbial biomass C with the practices of chloroform-fumligation method used in our works, a new method by the way of heat-sterilization, salt-extraction and volumetric analysis for measuring Microbial biomass C in acid soil is suggested. This methed is more convenient and efficient, and the measuring period can be, greatly shortened as conpared with tlxe chloroformfumigation method.

Abstract:The N₂-fixing capacity of locust nodule was high in neutral, low calcium and weak acid soils, but low in strong acid and strong calcareous soils of the Sichuan Basin of China. The relationship between iocust nitrogen fixation capacity and physico-chemical properties could be expressed by a multivariate regression equation. In course of fitting into the equation the authors advanced the method converting the nonlinear factors into linear ones, and simulated the interaction between the soil's factors with an electronic computer. In 42 forest soils avaifable P, and its interaction with CO₂-biological activity and total P₂O₅ were the main factors,influencing nitrogen fixation, and coordinations between pH and CaCO₃, and total P20s (ineluding available P) and available Mo made important contributions to nitrogen fixation as well. The equation can be applied to evaluate and forecast Na-fixing potential of the symbionts under different soil conditions.

Abstract:近年来作者在进行“黄土坡面产流实验与模拟的研究”等课题的研究中,研制了室内一维土柱入渗装置系统.该系统对于均质扰动土柱及原状土柱,在降雨入渗或积水入渗条件下的入渗率以及土壤水在剖面上的分布,分别采用了自动跟踪测量和放射性同位素测量,并利用计算机对数据进行实时釆集和处理,提高了量测精度,减少了人为差错,同时又便利了试验资料的整理分析,因而,为非饱和土壤水运动的试验研究提供了先进的测试手段.该试验装置系统的组成见图1所示.

Abstract:1977年中国农科院土肥所在山东省进行土壤有效锌普查^[1],估算全省缺锌1500万亩,并通过试验,指导锌肥大面积应用.近10多年来,在原认为土壤有效锌含量较高的地区,施锌效果也很明显,实践中锌肥应用方法、数量和后效等问题有待解决.