An annular wetland typical in the Sanjiang Plain was chosen as a case study on wetland biodiversity.Based on data of the previous field investigations and studies,status quo of the habitat diversity and species diversity of annular wetlands and causes of their formation were studied and the relationship between the two were explored.The results show that the habitat diversity was rather complicated and rich,and was formed and maintained through interaction between hydrography and topography on various spatial and temporal scales.The richness index and Shannon-Wiener index increased at first and then decreased along the radius from the center to the rim of the annular wetland,reaching the apex with the Carex casiocaepa community and getting lower with the Carex pseudocuraica and Salixbrachypoda-Salixmyrtilloides communities.The species diversity was rich in the annular wetland.Large-sized soil animals were the highest in diversity and homogeneity indexes and the lowest in superiority index in the reed-sedge communities,and so were medium-and-pint-sized soil animals in the Calamagrosticsangustifolia paludified meadow.The species diversity is closely related to the habitat diversity in the annular wetland of the Sanjiang Plain.

Since the Policy of Converting Polders Back into Wetlands was promulgated in the Dongting Lake Region,some arable lands have been changed into secondary wetlands,of which the ecosystem functions are being changed remarkably.Utilization and management of secondary wetlands should differ from that of natural wetlands.Strategies for ecosystem management of the secondary wetlands in the Dongting Lake Region are proposed,based on analysis of the functional change of wetlands,characters of wetland functions and the management of wetlands.Additionally,the countermeasures are brought out,aiming at the existing problems in the management.

Growth,leaf water potential,stomatal conductance,leaf photosynthesis(photosynthetic light response curve),and contents of flavonol glycoside,terpene lactone,starch and soluble sugar were investigated in saplings of two-year-old Ginkgo biloba subjected to drought,high night temperature(30 ℃)and drought*high night temperature,in order to determine effects of drought,high temperature and their interaction on these parameters.The results show that compared to saplings free from drought and high temperature in CK,the saplings under high temperature decreased in maximum net photosynthetic rate,leaf water potential and root/shoot ratio,but increased in stomatal conductance and light compensation point,and changes in light saturation point,flavonol glycoside and terpene lactone were not significant.Saplings subjected to drought got lower in maximum net photosynthetic rate,stomatal conductance and leaf water potential,but higher in light compensation,and remained almost unchanged in root/shoot ratio,apparent quantum yield and light saturation point.Under the interaction of high temperature and drought,the saplings rose in light compensation point and dark respiration rate,but fell markedly in light saturation point,and contents of flavonol glycoside and terpene lactone.Although there was no significant change in root/shoot ratio,the total dry weight per plant decreased.The findings suggest that drought and high temperature not only decreased the adaptability to light,light use efficiency,and stomatal conductance of the saplings,but increased dark respiration rate,thus resulting in inhibited growth.High temperature had greater impact on secondary metabolites than drought.

Characteristics and tolerance of three species of ectomycorrhizal fungi,Boletus edulis,Xerocomus chrysenteron and Gomphidius viscidus,growing in media different in concentration of sodium salts and in extracting solution of the saline soil collected from Dongying were studied.The results show that all of the Na treatments stimulated growth and biomass accumulation of B.edulis,but significantly inhibited growth of X.chrysenteron and G.viscidus.In the treatment of saline soil solution growth of all the 3 species was inhibited to an extremely significant extent,which is presumably related to lack of other essential nutrients and excess of K and Cl.In Na treatments,the content of Na in mycelia increased with the Na concentration in the medium,indicating strong Na absorption capacity of mycelia.However,remarkable differences could be observed in absorption and accumulation of sodium between the 3 strains of tested ectomycorrhizal fungi.

After years of treatment and management,the ecosystem of the Suzhou Creek is becoming healthier gradually.Surveys were carried out at 8 sampling sites along the creek in the period from October 2000 to April 2003.Findings of the surveys indicate that Bellamya aeruginosa,Bellamya purificata,Tubifex sinicus,and Limnodrilus hoffmeisteri were the predominant species in the zoobenthos communities in the creek.Though the communities were composed of more species than in 1999,they were still mostly pollution-tolerant ones.Comparison analysis of different aquatic ecosystems show that the structure of the zoobenthos communities is closely related to the pollution degree.Based on the correlation,a zoobenthos restoration index was established,objectively reflecting dynamic processes of the restoration of the zoobenthos community structure.Presently,the index of the Suzhou Creek shows a rising trend,and the restoration is obvious.

Spatio-temperal dynamic changes in ponding and enclosure culture in the Taihu Lake were studied with the aid of Landsat TM,Landsat ETM⁺ and aerial photography.The results show that a total of 4.45 km² of water surface was turned into ponds for fish-rearing in the period from 1984 to 2003.The exploitation proceeded at a much lower rate and on a much smaller scale than that in the period from the 1950′s to the mid-1970′s,and took place mainly in Suzhou.Enclosure culture has been developing rapidly in the Taihu Lake,especially since 1995.Its area was 13.17 km² in 1990,and expanded to (25.95) km² in 1995 and 107.72 km² in 2003.The expansion rate of enclosure culture in (1995-2003) was four times as high as that in (1990-1995.)A large proportion of enclosure culture occurred in the East Taihu Lake,and used up 81.90% of its water surface in 2003.

A field experiment was conducted to estimate quantitatively P loss from rice fields applied with different rates of P fertilizer.The ground parts of the crop removed about 47.5 kg·hm^-2 P from the paddy field.The quantities of P loss with runoff and the amounts of P enrichment in the （0-10） cm surface soil were linearly related to the rates of P application.The loss of total P with runoff ranged from 1.3 to 5.1 kg·hm^-2 and increased with the P application rate.It could be concluded that although excessive P application would increase the risk of P loss with runoff from the paddy field,the amount of P loss in the side bleaching paddy soil was low at the present local P application rate,and that the application rate of 50 kg·hm^-2 P during the rice growth season in the side bleaching paddy soil was acceptable.

The study was carried out in the Meicun Watershed,Xuancheng County,Anhui Province,in the northern subtropical low hilly areas by monitoring stream water,in order to illustrate characteristics of nitrogen and phosphorus discharge with surface runoff.The results show that nitrate was the main form of the nitrogen discharged,accounting for 60% of the total lost nitrogen,while particulate-associated phosphorus（PAP）was the main form,accounting for more than 90% of the total phosphorus discharged.There existed positive linear relationships between NO^-₃-N,NH⁺₄-N and total nitrogen（TN）.The discharge of PAP was correlated well with suspended particulates.A significant logarithmic relationship was observed between the discharges of dissolved phosphorus（DP）and PAP.A dramatic seasonal change of nitrogen and phosphorus discharges with runoff was found,showing a decreasing sequence of summer>spring>autumn>winter as a result of seasonal rainfall distribution.Furthermore,rainstorms contributed the most to the discharge of nutrients.Therefore,soil erosion control should be an effective countermeasure in limiting nitrogen and phosphorus loss in the rainy season.

Contents of nitrate and nitrite in leafy vegetable and in vegetable soil as affected by combined applications of organic and chemical fertilizers were determined through plot experiment and laboratory analysis.The results show that the combined application of chemical and organic fertilizers decreased the contents of nitrate in the vegetable and the soil,and reduced downward leaching of nitrate in the soil significantly.Especially when the ratio of organic manure and chemical fertilizer was 1∶1 much better effects could be observed,such as higher yield of Chinese cabbage,and lower nitrate concentration in the vegetable and in the subsoil of the vegetable field.

Through fields-scale experiment and leaching-pond experiment,characteristics of the loss of water-resolvable pesticides from rice fields and their affecting factors were studied.In the experiment,the losses of monosaltap and dimethoate were estimated.The results show that the loss of monosultap by way of drainage and leakage was 208.0 and 222.0 (g·hm^-2),respectively,forming a total loss percentage of about 14.3%;while the loss of dimethoate via drainage and leakage was 238.5 and 160.8 g·hm^-2,respectively,forming a total loss percentage of about 13.4% from the rice fields.

Open-top fumigation chambers were developed to study effects of gaseous fluoride on fluoride content in root,stem and vagina and leaf-blade of rice plant and in brown rice.It was found that airborne fluoride accumulated mainly in leaves.Fluoride content in the roots of rice was unaffected by airborne gaseous fluoride.Fluoride accumulation in the seeds depended on fluoride concentration in the air only after the seed organ arose.Fluoride accumulation in brown rice was in extremely significant linear relationship with the dose of fluoride in the air the spike is exposed to after full heading of the plant.

In order to study heavy metal pollution of the soils and wheat grains alongside the Shanghai-Nanjing Expressway,a survey was carried out with soil samples and wheat samples collected from different sections of the expressway.The results show that the soils within the 250 m wide zones along either side of the expressway and grains of the wheat growing thereupon were polluted with lead to a various extent.The maximum Pb contamination index reached 3.26 in the soil of Suzhou section of the expressway.The pollution of other heavy metals was not significant.According to the national standards for food,the content of Pb in the wheat grains exceeded the standard seriously,while the contents of other heavy metals were lower than the standards.The maximum content of Pb occurred in soils 100 m away from the expressway to either side.While,the maximum content of Pb in wheat grains appeared in places (50-100) m away.It could be concluded that Pb pollution on both sides of highways is still one of the major environmental problems affecting the safety of soil and agricultural products.

Elodea nuttalli,Potamogeton maackianus and Alternanthera philoxeroides were crushed,pressed and then filtrated to get filtrate of hydrophyte as fermentation material.Effects of varying levels of anaerobic sludge and additional N on liquid state fermentation were studied.The results show that highest biogas production（863.2 mL）in which CH₄ content was 720～750 mL·L^-1 in produced biogas and COD_Cr removal rate（90%） were reached within 10 days after 200 mL·L^-1 of anaerobic sludge was added.Biogas production from anaerobic fermentation of press filtrate of Elodea nuttalli,Potamogeton maackianus and Alternanthera philoxeroides was increased by 2%,10% and 30%,respectively,when 1 g·kg^-1 N was （added）.

Compared with urban settlement ecology,rural settlement ecology has not received much attention in China with theories and methods immature. In order to stimulate studies on rural settlement ecology,the traditional Chinese ideas on settlement ecology,studies of rural settlement ecology in China and other countries are reviewed. 

Ecological risk assessments(ERA)of pesticides in China,USA and OECD are introduced from such aspects as guidelines,methods, and models of the assessments and the important role of risk assessment in pesticide registration,and researches in these fields are reviewed.Shortages of the country in this aspect are exposed and recommendations are brought forth to make up the shortages. 

Variation of carbon fluxes of Epikarst was discovered through observation at Mt.Jinfo in Chongqing on August 15th in the summer of 2002.This investigation aimed at depicting change in CO₂ concentration in Epikarst under different vegetations in summer.Variation of soil temperature was getting smaller in range with the soil depth in both forest land and barren land,but it was smaller in the former than in the latter.Variation of CO₂ concentration was significantly related to soil temperature regimes,showing a similar trend that the variation was smaller in the forest land than in the barren land.CO₂ concentration increased with the soil depth.In terms of soil temperature in different soil layers and variation of soil temperature,soils under different vegetations were lined in the order of forestland>shrubland>grassland.The variation of soil temperature in forestland lagged about 3 hours behind that of the air temperature.

An ecosystem is often multiple in function,different in consistency.Based on key services and service compatibility,an ecosystem can be divided into many zones.Wetlands of the Hongze Lake,rich in biospecies diversity,are important laky wetlands in Jiangsu Province and have 11 different kinds of ecological service functions.Using the method of consistency analysis,the wetlands of the Hongze Lake can be divided into six ecological function zones,i.e.important species inhabiting zone,lacustrine aquiculture zone,aquatic products intensively rearing zone,water source supply zone,social and cultural zone and pollutant decomposing zone.Relevant protection measures are presented to bring about important ecological,economical and social efficiency for the wetlands of the Hongze Lake.

Aiming at existing problems with methods for safety assessment of herbicide-resistant transgenic crops,a new method based on affinity of plants for safety assessment of gene flow was put forward.Criteria for selection of allied species were explored with time dependence sequence,space dependence sequence and population quantity dependence sequence as its principles.

According to correlative regulations of the State Environmental Protection Administration,the function zones of the Taihangshan Macaca mulatto chinensis National Nature Reserve must be readjusted because the planned Jijin Expressway will traverse the core and buffer zones of the nature reserve.The ecological impact of the expressway project on the nature reserve has been assessed.The integrated influence of the readjustment on Macaca mulatto chinensis and other species in the nature reserve are analyzed,and advices and countermeasures for environmental protection and compensation are put forward.