Abstract:This paper deals with the effect of application of organic materials on the properties of humic substances in organo-mineral complexes (organic matter in heavy fraction) of silt loamy chernozem and clay loamy light saline meadow soil with Field,pot and culture experiment for two years.The results obtained are summarized as follows:When organic materials applied to the soils the contents of organic matter in soils and in complexes were markly increased.The effects of various organic materials were in the following sequence:peat> distiller's grains> sawdust>corn stalk> soybean stalk > horse excrement>sugarbeet residues.

Abstract:The present paper deals with the composition of the newly formed humus derived from various plant materials decomposed in a Quaternary red clay and in a in a Xiashu loess for 3 years.Experiment results showed that 1.the ratio cf C/org.N and fractional humus composition of newly formed humus varied with the kinds of plant material from which it was derived:2.as compared with those formed under submerged conditions,the newly formed humus formed under upland condition had higher C/org.N and hexoses/pentoses ratios and sugar content as well as a higher extractability of humic substances;3.the newly formed humus formed in Xiashu loess had a lower C/org.N ratio,but higher HA/FA and hexoses/pentoses ratios than that in Quaternary red clay.The role of clay mineral in the formation of humic substances is discussed.

Abstract:Effects of pig manure on properties of yellow-brown earth were studied in a incubation experiment for 427 days under submerged condition without percolation.Manure applied at the rates of 0 (as the check),1,3,5,7 and 9% of soil weight.The results indicated that the decomposition rate of manure was not influenced by the application rate.The organic material in the manure remained in the soil was 54.870,of which 38.7% was transformed into soil organic matter and 16.1% undecomposed;62.3% of nitrogen of the manuer remained in the soil.Hydrolyzable N was closely related to the soil total N (r=0.985^**,n=18).

Abstract:The ecological distribution of denitrifying bacteria in the three soils on rhizoplane and in rhizosphere of rice and barley was studied.Results showed that the total amount of bacteria was larger on rhizoplane than in rhizosphere and non-rhizosphere soil in each growing period of rice.The ratio of R/S was above 10-100.The total amounts of bacteria or denitrifying bacteria in rice and barley rhizosphere attained to the maximum during heading period,however,there was a marked dropping in ripening period.It was clear that the amount of bacteria in rhizosphere of rice was higher than that in rhizosphere of barley in each corresponding period.

Abstract:The peak output of rice can be calculated from the basic fertility of soil with an equation proposed by the authors.In this paper,an additional equation to calculate the requirement of N for the predicted maximum yield of rice are proposed as follows:
N_R=(0.018(Y-1.05X)/E_F
where X is the yield of rice on certain rice field without fertilization,Y,the maximum obtainable yield of rice on the same field well fertilized.N,nitrogen requirement for yield Y,E_r,efficiency of the fertilizer applied.Experiments has shown that the eqation a practicable.

Abstract:The effects of pH,temperature and soil components on Zn adsorption in calcareous soils were studied.The soil samples were collected from the surface layer (0-15 cm) of yellow fluvo-aquic soil in Fongxian,Jiangsu.The experimental results showed that fitting of the adsorption data to the Langmuir equation,the Langmuir plots should be split into two linear portions.This may be considered that two Langmuir type surfaces existed.The adsorption maxirtia determined by a method based on the moving of the origin of coordinates approximately agreed with the experimental results.The effect of pH on Zn adsorption was very significant.At high pH range (7.5),the contribution of CaCO₃ to Zn adsorption was approximately 70% of the total amount adsorbed.At low pH the contribution bzcame less significant.The zdsorption capacity increased with increasing the temperature.

Abstract:Three simplified methods for estimating the volatilization of ammonia from flooded rice.fields were assessed when the plants are small and sparse in the field at Lianhu Farm,China.The most accurate and reliable technique involved the measurements of wind speed and anmonia concentrations in the atmosphere at 0.8 m above the floodwater surface.A slightly less reliable estimation could be obtained with a specially designed ammonia sampler which gave a measure of the horizontal transport of ammonia at a fixed height.In remote locations the sampler method may be preferred because electrical power,pumps,flow meters and anemometers are not required.

Abstract:Experiment was made to verify the fractrination of organic Phosphorus in paddy soils of southeastern Hubei by Bowman-Cole's method.Results obtained showed that the rates of mineralization of the four organic phosphorus fractions (labile P,moderately labile P,moderately resistant P,highly resistant P) in the soils tended to increase with the enhance of their activity.As a result,the method of organic phosphorus fractionation can be used to monitor soil organic phosphorus availability for plants.

Abstract:The biomass and biological nutrient cycling in a Korean pine-broad leaved forest stand of Natural Reserve in the Changbai Mountains of Jilin provice were studied.Results showed that the total biomass of the stand was 210,944 kg/ha,the biomass of the above ground parts constituted 82%,and that of below ground parts 18%.lts total annual production was 7087 kg/ha,and chat of herbs was 3.43%.The contents of N,P,K,Ca 2nd Mg in the above ground biomass in the stand was 618.6,56.47,511.82,1057.95 and 75.35 kg/ha,and their amounts of annual biomass production was 78.58,7.72,45.80,84.51 and 13.97 kg/ha respectively.The percentage of nutrients uptake by trees constituted 73-92% of the total annual nutrient requirement.Althrough the biomass production of herbs only constituted 3.4% of the total biomass production,the amounts of nutrient in the production of them constituted 7-26% of the total annual nutrient require requirement to meat.

Abstract:Chemical,mineralogical and micro-morphological properties of ferric allitic soils derived from basalts of different age in Leiahou Penisula and Hainan Island were studied.The results showed that,with the lapse of soil of forming age (Q₄-Q₁),primary minerals was getting less,the crystalinity of kaolinite became better,CEC deceased obviously,and so did the SiO₂/Al₂O₃,ratio of clay from Q₃ to Q₁,dithionitecitrate-extractable iron content increased gradually.

Abstract:Principal component analysis,cluster analysis,discriminant analysis and a graphtheoretical method were used for the classification of forest soils in region of the Hongduan Mountains.30 forest}oil profiles were divided into six groups based on their chemical and physical properties.The results obtained from the numerical methods well conformed to the most importanr genetic conditions of the soils,i.e.the forest vegetation types.In the high-mountain forest region of Southwest China,the major soil forming processes are eluviation (acid leaching) and humification.Results of principal component analysis of 6 physical and chemical indexes of the soils indicated that the soils grouping could reflect the major processes mentioned above,while discriminant analysis of the soils gave the distinct delimition of each soil group.The two methods in combination may be the basic methed for soil numerical classification.

Abstract:由于人类的各种活动使环境受到不同程度的污染,故环境背景值的研究便成为环境质量评价研究的基础性工作,它不仅用于当前的环境质量评价及环境监测工作,而且对工农业的规划及发展也具有实际意义.我们对湘江谷地主要土壤类型中B,V,Sc和Ba等若干元素的环境背景值进行了初步研究,现报告如下.