Based on summary of major problems existing and experience accumulated in setting up Chinese nature reserve classification standard,and taking the present status and characteristics of construction and management of nature reserves in China and the IUCN protected area categories as reference,a recommended classification standard for nature reserves in China was brought forth and all the existing nature reserves were re-categorized in the hope that the work will provide some beneficial reference for construction and management of nature reserves and international and domestic communications in this aspect.

For choosing residential areas,five major factors should be taken into account.Detailed contents and requirements of some of them,such as eco-recycle,Fengshui(relationship between the geographical site and the ecology)and ecological civilization were explored. 更多还原 AbstractFilter('EnChDivSummary','ChDivSummaryMore2','ChDivSummaryReset2');

Change in land use and its effects are important contents of the study on global change. Land use structure and temporal variation of total grain output were analyzed on the basis of 1996 to 2001 data. Based on the results of the analysis the effects of land use change on grain production were further discussed.

Though the Heihe River is one of the largest inland rivers in northwest China,its water supply is far from adequate to meet the water demand.In order to practice water allocation,water saving irrigation,and integrated management of the water resource,a study was carried out to make use of TOPMODEL in simulating the hydrological processes of the Yingluoxia Catchment(10 009 km²)in Heihe region.Traditionally,only data from the end station of this area were used as grid data of the whole catchment.They couldn′t describe the spatial variation of altitude-dependent precipitation in such a large basin.Hence,based on DEM precipitation data from about 10 stations were interpolated by using the PRISM approach with major control factors such as altitude,landform and distance.On the premise that the comparison between the results of the interpolation and the data of field investigation showed improved precision.TOPMODEL was then used to simulate daily volume of runoff in the catchment with satisfactory results,being 70% or so in prediction precision.

A study was carried out on species and specific composition of aquatic microorganisms in fish-rice ecosystem in soda saline-alkaline land of the Songnen Plain.The results showed that population of heterotrophic bacteria in the fish-rice （ecosystem） was 2 800—307 160 mL^-1,higher than that in the normal rice farming system（P<0.05）,with the order of rice growth last-term>middle-term>primary-term.The density of actinomyces and molds was low in both the two ecosystems.The population of coliform in the fish-rice （ecosystem） was 403.6—17 934.2 L^-1,higher than that in the normal rice farming system（P<0.01）,with the order of rice growth middle-term>primary-term>last-term.The population of heterotrophic bacteria was significantly related to fish production,total amount of fertilizer applied and quantity of organic manure applied,but not to the application rate of chemical fertilizer;the population of coliform was also closely related to fish production,but not to the total amount of fertilizer applied.Nevertheless,it showed extremely significant relationship with the application rate of organic manure.Ten genera of heterotrophic bacteria were detected in the fish-rice ecosystem with Vibrion,Aeromonas,and Bacillus being the dominant groups.

Effects of enhanced ultraviolet radiation(UV-B radiation,broad band with 280 to 400 nm)on winter wheat were investigated.The results indicated that enhanced UV-B radiation made the plant shorter,leaves smaller,spikes,stalks and leave lighter,the speed of milking slower and grains less plump,thus affecting the yield of the plant. 更多还原 AbstractFilter('EnChDivSummary','ChDivSummaryMore2','ChDivSummaryReset2');

Based on a stationary experiment,soil water leaching deep drainage and nitrate-N loss with leachate in a soil（yellow fluvo-aquic soil）representative of the Huang-Huai-Hai Plain were simulated with the HYDRUS-1D model.The results showed that under conventional water and nitrogen management,percolation of soil water and nitrate leaching were very serious in the soil,causing a loss of about 23.7% of the total amount of irrigation and precipitation,and about 15.9% of the total N applied during two successive rotations;the amount of nitrate leaching in the season of winter wheat was higher than in the season of summer maize;and the modified irrigation and fertilization management pattern reduces the nitrate-N loss by 74.7% as was compared with the conventional one,thus saving 211.5 mm of irrigation water and N 423.5 kg·hm^-2.

Based on the flow characteristics and pollutant distribution of Dagu River,QUAL2E model,a comprehensive water quality model,was chosen to simulate and predict water quality in the Qingdao section of the main stream of Dagu River, with BOD₅,COD and nitrogen as indexes for simulation and prediction.Some important quality parameters,such as BOD decay coefficient（k₁）,reaeration coefficient（k₂）,BOD settling coefficient（k₃）,COD decay coefficient and dispersion coefficient,were determinated through experimental simulation and by using the model rating method and referring to related literature.The simulation results were verified and showed that the predicted values agreed with the measured ones extremely well.The sensitivity analysis of BOD₅,k₁,k₂,and Q（flux）was also carried out.The results showed that the parameters influencing the concentration of oxygen were lined in the order of Q,k₂,BOD and k₁ in sensitivity.Q is the most sensitive parameter,indicating that hydraulic parameters of the river have a greater influence on DO.The water quality simulation of Dagu River provided basal data for calculating the water environmental capacity of Dagu River and implementing the pollutants total control,as well as scientific evidence for the supervisors and decision-makers of water pollution control.

Long-term stationary monitoring for 3 years in a row was conducted of soil and water loss in citrus orchards of (2 different) types of set-up,and studies carried out of annual dynamic changes in soil water content in 4 types of citrus (orchards) in northwest Guangxi.The results showed that generally soil and water loss declined year after year in the 2 citrus orchards of different set-up,and the runoff coefficient of the orchard on slopeland was higher than that on terraced fields;The soil moisture contents were related to soil profile,set-up of the orchard and parent material of the soil,and in particular positively to the monthly rainfall.Therefore,different measures for management of soil water regime should be adopted for these orchards in different month. 

Agro-environment awareness and corresponding behavior choices of some essential technical and economic policies as well as even legislative countermeasures were investigated in a high-yielding farmland county in northern China.The contingent valuation method(CVM)was used to evaluate the public′s Willingness to pay(WTP)for the nonpoint source pollution resulting from intensive farming.Survey results showed that more than 60% of the interviewers expressed concerns on the environment health for their future generations.As high as 76% of the subjects revealed positive attitudes toward dealing with the pollution and protecting the environment from further deterioration.The averaged WTP was 22.8 yuan/year per capita.However,the public′s awareness of the potential threats caused by farming was at a quite low level.Willingness to pay mainly depended on such factors as family income,education level and occupation.Based on the population,the total WTP of the county was estimated at about 11.1-13.2 million yuan/year,which could be the best base for charging the fee.To improve conventional farming practices,especially over-fertilization,would be the most efficient technical measure.In contrast,legislation and strict regulations may not work efficiently due to the relatively weak environmental awareness of the public. 

One simple, quick and low-cost method for the composting of livestock manure was suggested.A square cement fermentation pool was set up with the bottom and one side built with bamboo poles to improve supply of oxygen.Semi-matured compost was applied to adjust moisture content of the materials.The pile rose quickly and high in temperature,gave off large volumes of vapor,and fermented quickly,thus shortening the time for primary fermentation to 2 or 3 weeks.Such a technique is applicable for small- or middle-scale livestock farms in China.

Heavy metal pollution assessment has been successfully applied to studies on river,lake,ocean,and soil environments,but not too much on marshes,especially on time sequence of heavy metal pollution.Sediment can be considered the sink and end-result area for the heavy metals imported into water.Here a case study was reported of the Xianghai marsh at downstream of an inland river—Huolin River.High resolution analysis of the samples gathered from profiles in the marsh was performed with the aid of radionuclide timing and heavy metal pollution assessment,and based on normalization of heavy metals to aluminum in sediment in the typical profiles,heavy metal pollution and enrichment levels and time sequence were analyzed and compared using the methods of comparison between upper and lower layers,sediment enrichment factor(K_SEF),index of geoaccumulation(I_geo).The results showed that within the upper layer of the profiles,significant enrichment of heavy metals was observed up to the level of pollution,indicating that the disturbance of the wetlands downstreams caused by human activities in the upper and middle reaches of Huolin River has been intensifying in recent 20 years.

Soil property and heavy metal content of agriculture soil in the suburbs of Guangzhou were studied to analyse relations between soil property and soil heavy metal content.The results showed that the 70.5% of the samples gathered in the suburbs of Guangzhou were loamy soil with an average pH value being 5.93,and an average content of organic matter being 317 g·kg^-1.Though not high, CEC of the soil varied greatly from site to site.The distribution of Cu,Pb,Zn,Cr,Ni,Cd,As and Hg differed in garden soil,latosolic red soil and paddy soil.The results of correlation analysis showed that the relations between soil heavy metal and the soil property were very complicated.

Dachang Mining is a famous tin production base of China.Nowadays,most of the abandoned mine tailings dumping grounds are uncovered,resulting in serious regional environmental problems.A field revegetation experiment,composed of 3 treatments,CK,adding in garbage compost,and covering with soil,was carried out on an abandoned tin mine tailing dumping ground at Dachang Mining.The tailings were first amended with garbage compost and soil,and then Leucaena leucocephala trees were planted.In the first 100 days,L.leucocephala on the tailings amended with garbage compost were found growing best.The results showed that the garbage compost significantly decreased plant uptake of heavy metals from the soil,indicating that in the process of vegetation restoration on tin mine tailings dumping grounds,garbage compost can substitute soil,and L.leucocephala can be planted as the pioneer species. 

Determination of concentrations of the total and soluble forms of Fe,Mn,Cu,Pb,Zn,Cd,and Hg in some chemical fertilizers used in the country was conducted.The results showed that in the nitrogenous fertilizers and potash fertilizers,the content of heavy metals is relatively low while in the compound fertilizers and phosphorus fertilizer it is relatively high.In most of the chemical fertilizers,the contents of Cu,Pb,Zn,and Cd are controlled below the second grade standard for soil environmental quality and hence safe to use.But in some of the compound fertilizers and the nitrogenous fertilizer produced through sweetening with electron beam,the content of Hg well exceeded the standard,and Zn too.The use of these fertilizers,therefore,may have certain environmental risks. 

The acute and chronic toxicities of acrylamide are measured using Daphnia magna as test organism. The 24 h-LC₅₀and 48 h-LC₅₀ value of acrylamide to this species is 173.21 and 89.59 mg·L^-1,respectively. The results of 21 d life cycle test show that the reproduction of Daphnia magna is the most sensitive parameter of chronic toxicity to this chemical.The value of non-observed effect concentration（NOEC）on reproduction and the lowest observed effect concentration（LOEC）on reproduction of acrylamide to this species is 1.56 mg·L^-1 and 3.13 mg·L^-1,respectively.The maxium acceptable toxicant concentration（MATC）of acrylamide to Daphnia magna is 2.47 mg·L^-1,which is estimated on the basis of the above two values. 

According to the investigation on the status quo of the cropping and grazing in Ningxia Autonomous Region and the comparison with what was around 20 years ago,a big headway has been made in its agricultural economy, but problems do exist with equilibrium of the agricultural structure.The long-promoted model of laying stress on cropping and neglecting grazing has proved to be a directional lapse in developing grassland agriculture.For the sake of remediation,the following issues,such as ecological basis for restructuring of the agriculture in Ningxia,directions of readjustment on a district-by-district basis and new trains of thoughts for restructuring,are explored.

Based on comparison of Chinese nature reserve classification with IUCN protected area catagories,it is recommended that a new nature reserve classification system of China should be established in light of the status quo of the conservation of biodiversity,natural and cultural resources in China,and by referring to IUCN protected area categories.The new system should adopt major management targets of each reserve as its basic principle for the sorting and meanwhile take into account comprehensively characteristics of protected objects and extent of human disturbance,so as to realize the dual targets of conservation and sustainable development of nature reserves.

Investigation and analysis conducted recently of the production,safety and quality of aquatic products in China showed that the industry has been developing rapidly,though,promoting growth of the rural economy and improving the diet structure of the people,problems in quality and safety with its products are getting more and more prominent.Hormones,antibiotics,heavy metals,pesticide residue,additives and micro-organisms in products are found exceeding the criteria for hygiene.There are quite a number of factors related to these problems,such as environmental pollution,laws and rules,monitoring methods,governmental administration etc.On the basis of the analysis,strategies to solve the problems are put forth.