Based on the 30-years’ rainfall data of a repre-sentative meterological station and the 25-years’rainfall data of 43 hydrometric stations in the Taihu Lake reglon,the new algorIthn of rainfall erosivity factor(R-value)was improved which showed a coincidence with the classical algorithm at the rdte of 9O% of the temporal and spacial variation characteris-tics of R-value in the Taihu Lake region or Changjiang biver basin,and the R-value(25-years’)distribution map in the whole region was compiled as well.Applicatlon of R-value to soil and water conservation,tillage system transformation,flood prevention and disaster mitigation and,in particular,the fundamental reason for the big flood disaster in 1991 in Taihu Lake region were discussed.Owing to the larger R-value in this region, the soil conservation should not be ignored.Adopting soil conservation measures in the mountainous ar-eas,especially for the slope land,constitutes a basically per-manent and effective method for flood prevention and disaster mitigation. 

Nutrient cycling rule in paulownia and crop in-tercropping system,in which paulownia was mainly consid-ered,was studied.TheresultS showed that the contents of nu-trient elernents in different organ;of Paulownia varied with seasons;the annual total uptake of nutrient elerments was 471.96kg/hm²,composed of N 155.14kg/hm².P 80.08kg/hm².K87.04kg/hm².Ca 119.46kg/hm² and Mg 30.23kg/hm², the annual return amount of nutrient elements was 331.62kg/hm²,composed of N 102.57kg/hm², P 43.29kg/hm²,K 63.65kg/hm²,Ca 97.36kg/hm² and Mg 24.74kg/hm². The circulation rate of nutrient elements was 70.26%,com-Dosed of N 66.11%,P 54.06%,K 73.13%,Ca 81.50%and Mg81.81%. 

Nitrous oxide emissions were measured inthree corn plots by different N-fertilized treatments from Juneto september in 1993.During the growing season of corn,theaverages of N₂O fluxes from control, urea-treated,and ma-nure-treated plots were 8.5±2.2,18.9±11.7 and 15.4±5.9μg N/m²·h,respectively. Calculation is made on the lossrate of fertilizer as N₂O. The emission coefficients of urea andorganic manure were 0.19%and 0.12%,respectively.

On the basis of the principle of ecological eco-nomicx,comparative study of energy flow and nitrogen con-version for the strawberry preduction system between man-agement in organic and inorganic ways was studied. The re-sults showed that although almost same amount of N applied in organic(175kg/hm²)and inorganic(164kg/hm²)treatment,the growth,development and yield of the strawberry in organic treatment was better than that in inorganic treatment during strawberry growth period,The utilization rate of solar energy and output/input ratio of nitrogen in organic treatment were 64.24%and 57.72%higher than those in inorganic treatment respectively. The result also proved biogas slurry is a good or-ganic manure and can improve the fruit quality of strawberry and bring sound economic benefit. 

The low-lying saline-alkali wetland is one of main type of low yield fields in Huang-Huai-Hai Plain. Ac-cording to the resource of water, quantity of heat and wet-land, the lowland was integratedly treated and utilized withthe model of digging fish ponds and building raised fields. Bymonitoring the moving of the salt and wdter,the engineeringsolved the question about preveting secondary saline-alkali of wetland.The monitoring results showed that soil organicmatter was increased from 0.582%to0. 989%, total N and Pcontents were increased from 0.02% and0.14% to 0.061%and 0.158% separately, and soil salt content was reducedfrom 0.50-0.92% to 0.06-0.29% year by year in the re-formed land.The integrated environmental benefit indicatedthat the original land condition was soundly transformed and the planned goal of primary tretment and utilization wasachieved.

The main microclimate indexes in the planting orchard and the seedling nursery of Kangji Ecological Farm,Chengwu County of Shandong Province, as well as the waste land(for contrast)were separatively observed and analvzed with the method of comparative analysis. The results show that the planting orchard contributes to the increase of the av-erage daily air-temperature during the earlier plant growth stage and the relative air humidity in the dry season,to the ob-vious decrease of the maximum temperature at the soil surface and the wind speed in the gale season. Therefore,planting or-chard plays a certain role on improving the microclimate of the farm.

This paper reported the mobility of 3 pesti-cides(Aldicarb,Carbofuran, Alachlor)in different texturesoils.The results showed that the mobility of the pesticides insoils was Aldicarb>Carbofuran>Alachlor.The recoveries ofthe pesticides through a 30 cm soil column were 88.0%forAldicarb,69.1% for Carbofuran and 1.84%for Alachlor.Theeffect of soils on the pesticide movement was less than that of pesticides.

This paPER presents the studies on the relativitiesbetween the death rate of cancer of the liver and the types ofrock(magnatic roak,metamorphic rock,carbonate rock,clasticrock,red clastic rock and friable rock of quaternary system)inthe living areas of people by means of the information of rocktypes with 1092 data and the investigations of 1544 examplesabout the death of cancer of the liver.On the basis of the study,the comprehensive appraisal on the influence of thetypes of rock which reldted to cancer of the liver as to the oc-currence and development of cancer of the liver was made. 

The cultivation of bamboo shoot(Phy. Prae-cox) has become an important economic income to farmers af-ter tea, mulberry and silk cocoon through our three yearsfarmers bomboo shoot production recording and whole town-ship bamboo cultivation investigation at Shanqiao Township ofDeqing County, Zhejiang Province. Bamboo shoot productionsystem has high output/input ratio and a simple techniqueneeded by farmers.Bamboo shoot production makes full use of the hilly and slope land resources and increases the land eco-nomic return ratio. Under the present production and manage-ment condition,the way to get high bamboo shoot yield forfarmers depend on increasing landacres,N and P fertilizers,furthermore it is necessary to adopt scientific and standardizedcultivation methods to promote fast and early growth of bam-boo shoot,to solve problems of primary proressing snd to de-velop fresh keeping technology.

With the principle of system dynamics (SD), this paper deals with the development and utilization of the small watershed resources in Taipinggou of Jianping Cuunty.The SD model flow diagram was drawn and SD model proce-dure was made. With the computer dynamic simulation,it is found that the“comprehensive development”is the main de-velopment and utilization direction of the small watershed re-sources. This study provides scientific bases and method for the small watershed economic construction and the agricultur-al development in the similar type watershed.

Based on the data monitored and the experi-ments conducted in the stream network in Wu xi County. theparameters in water quality model of stream networks wereestimated. 

This paper introduces the status quo and char-acteristics of pollution levy charged from township and villageindustrial enterprises (TVlEs),calculates the levy amountwhich should be charged from TVIEs according to the nationalTVIEs’polluting source survey data of 1989 and demonstratesthe amount from its impact on TVlEs,society, fiscal revenueand rural environmental protection and the collection feasibili-ty, analyzes the causes of low collecton rate of pollution levyfrom TVIEs and raises some recommendations about pollutionlevy collection , management and usage.

Based the fluxes of methane emissions fromtypical rice,this paper reports the estimation of methane e-missions from China ’s rice fields. The result shows that theoverall methane emissions from paddies were 11.335 Tg in 1990, The mitigation options,recommended for reducingmethane emissions include(1) application of methane in-hibitors in rice field;(2)nutrient management;(3)watermanagement;(4)select rice varieties with lowemission ratesand high productivity.

In this paper,approach for the construction of eco-farming in lateritic red soil areas at coastal region of Fu-jian Province was studied.By planting grasses and trees,har-nessing water and conserving soil to improve the eco-environ-ment,optimizing the agricuitural productive structure gradu-ally,establishing the efficient farming,recovering and in creasing the lasting productivity of cultivated land,protecting the productive function of agricultural living things,exploring the fruit production,enhancing the animal husbandry,pro-cessing and utilizing agricultural side products,resolving the energy for the farmer’s living in the countryside developing courtyard ecological economy,the construction of lasting effi-cient agricultural productive system was studied to attain the all-round development of agriculrure in the coastal upland. 

According to the various responses of C₃ plant and C₄ plant to rising CO₂,the impact of the atmosphere con-taining enriched CO₂ on ecosystem is reviewed.It is concluded 1992)。that increasing atmosphere levels of CO₂ may lead to a series of changes in ecosystem, including the loss of biodiversity, the inhibition of mutrient cycling, the coming of plague of in-sects and the increase of greenhouse effect.

In this paper,the present situation and exist-ing problems of crop straw utilization in China were analyzed, the utilization approach and development value of crop straw were discussed, and the primary suggestions for the rational development and utilization of crop straw were proposed.

There are 121 rare and endangered plants inGuangxi Zhuang Autonomous Region, which is one of therichest regions in the distribution of rare and endangeredplants in China. Based on the assessment of the type,ar-rangernent and present situat ion of the natu re reserve con-struction in the region and on the conservation conditions ofthe resources of rare and endangered plants, suggestions,forthe nature reserve construct ion and effective protect ion ofthese plants in the region were propoxed.

The maximum principle,which is the important part of economics cybernetics, is introduced to the envi-ronmental economics. By this principle,a micro model is es-tablished and the method for solving this, model is also studied. 

The actue and cumulation toxicities of fournew pesticides on birds(quail)were studied,and their safetyassessment was carried out.The results showed:methylisofinphos and pyrimysthion were high toxic. It wassuggested by cumulation test that cumulation of pyriysthionwas moderate and cumulations of other three Desticides wereliw.