Based on a pressure-status-response(PSR)model,an ecological security evaluation index system which consists of 15 selected items was established.The ecological security of the Tuojiang River Basin in 2010,2015 and 2020 was predicted as early warning with the aid of the technologies of analytic hierarchy process(AHP),chronological prediction,fuzzy integrated evaluation,and principal component analysis.Results show that(1)on the whole the ecological security of the basin will be getting better and better in the years of 2010,2015 and 2020;(2)it will vary from section to section.It will be much better in the upper reaches than that in the middle and lower reaches,and in the middle reaches than in the lower reaches,so the lower reaches of the Tuojiang River Basin should be the major zone for concern;(3)in terms of mid-term ecological security early-warning,the basin can be sorted into three categories,i.e.safe region,consistently endangered region and degraded region.The safe region is composed of 21 counties(cities or districts)in the upper,middle and lower reaches,the endangered one,of 8 counties(cities or districts)in the middle and lower reaches;and degraded one,of 2 counties only in the middle reaches;and(4)the main factors for early-warning of ecological security in the period of 2010-2020 in the studied area can be concluded as six categories,i.e.vegetation coverage and agricultural disasters,rural population quality,land loading capacity,land use patterns,non-point source pollution,and soil erosion.Based on the findings in the study,the following ecological regulatory countermeasures are put forth:(1)to restore vegetation and improve eco-environment;(2)to enhance the capacity of the agriculture on preventing and standing natural disasters;(3)to strengthen skill training of the labor force and improve quality of the population;(4)to rationalize exploitation of the land resources and raise loading capacity of the land;(5)to optimize land use structure and increase landscape diversity;(6)to advocate biological control of pest,and control non-point source pollution;(7)to develop soil and water conservation projects.

Focusing on the nature of interregional relationship,the connotation of coordination degree is specified as a quantitative index to determine coordination degree within a system or between systems.On such a basis,proceeding with the coordination degree between the two sub-systems,i.e.socio-economy and resource-environment,indices are screened and an evaluation model built up.The indices and the model are tested in analyzing by phase coordination degree of the development of Xinjiang in the period from 1990 to 2003.Results show that the two sub-systems developed upwards,though in fluctuation,and the coordination degree between the two,on the whole,was gradually getting better.Comparison between the 87 counties and cities of Xinjiang in coordination degree demonstrated that spatial variation was quite notable.

Based on the 1982-2003 NOAA/AVHRR remote-sensing data published by GIMMS and the meteorological data of 53 natural meteorological stations in Xinjiang Autonomous Region during the period of 1982-2003,dynamics of NDVI and its temporal and spatial correlation with climate was studied.Results show that within the 22 years,annual variation of NDVI generally displayed a significant rising trend,with an annual mean rising rate of 0.59%,particularly in areas along the southern fringe of the Dzungaria Basin and the southwestern edge of the Tarim Basin.In summers and autumns,NDVI was significantly related to precipitation,and in the springs and autumns it was significantly related to temperature.Areas showing the latter are distributed mainly in the mountainous areas,like Altai Mountains in the north,Tianshan Mountain in the middle,and Kunlun Mountain and Altyn in the south,while areas showing the former in the plains,low lands and oases.

Species,mean coverage,mean density and α-diversity index of the understory herbaceous plants were investigated in five-year-old Liriodendron chinense forest stands different in canopy density in Chongming Island of Shanghai.Results show that with canopy density increasing from 0,(0,0.2],(0.2,0.4],(0.4,0.6],(0.6,0.8] and(0.8,1.0],the number of understory herbaceous plant species displayed a rising-and-then-falling trend,like 16,16,19,15,9 and 7.Significant negative correlations were observed between the canopy density and the mean coverage of herbaceous plants(r=-0.964 3,P<0.01)and the mean density of herbaceous plants(r=-0.981 5,P<0.01)as well.The Simpson index,Shannon-Weiner index,and Pielou index peaked when the canopy density was(0.2,0.4],being 0.754 8,1.327 3,and 0.880 6,respectively.

The study on effect of afforestation on forest micrometeorology has important implication for understanding forest ecosystems.A four-year study was carried out to observe and compare variation of the micrometeorology of three types of vegetation,i.e.Type A(Acasia crassicarpa forest),Type B(Eucalyptus grandis ×E.urophylla forest),and Type C(shrubbery + grasses)established on burned clearings of fir forests in the the northern suburbs of Nanning in Guangxi.Rresults show that(1)the average daily solar radiation of Type A and Type B was 126.6 and 90.8 W·m^-2,respectively,equaling to 50.4% and 36.1% of that of Type C,and declining with the age of the forests in a wave pattern;(2)the annual mean air temperature and ground temperature inside the two stands was 0.7-0.8 and 1.8-2.7 ℃ lower than on the shrub-grass land,and getting lower with the age of the stands;and the annual mean relative humidity of the air in both forest stands increased by 1-3 percentage points over that in the shrub-grass land,and the effect got more evident with the age of the stands;(3)the two short-cycled industrial timber forests,5 years in age,showed full effects like mature forest stands on the micrometeorology therein,and the effect of Acasia crassicarpa forest was more obvious than that of Eucalyptus grandis × E.urophylla forest.

Combining GIS with C_V value,the influences of environmental factors,like terrain,roads and rivers,on spatial distribution characteristics of rural settlements in Changping District of Beijing Municipality have been addressed.Results show that terrain is a leading factor.On plains,the rural settlements are quite large in scale and high in density,occupying a high proportion of the land,while in mountainous areas they form a contrast.Road is an important factor affecting distribution of settlements in the rural areas.About 91.19% of the rural settlements are located within the distance of 1 500 m from main highways.River is another factor.The farther away from a river,the less the density of settlements.

Characteristics of distribution and composition of sulfur in soils of typical meadow Calamagrostis angustifolia wetland and marsh meadow Calamagrostis angustifolia wetland in the Sanjiang Plain were studied.Results show that total sulfur in both wetlands are in the range from 303.39 to 520.83 mg·kg^-1 and from 303.74 to 1 219.81 mg·kg^-1,respectively,averaging 391.62 and 513.03 mg·kg^-1 respectively,both lower than the average of the world soil.Sulfur accumulates mainly in the upper layer of the soils in the form of organic sulfur,which constitutes about 90% of total sulfur.Carbon-bonded sulfur forms the largest portion of organic sulfur,accounting for 45.34% and 37.24%,respectively in the wetlands.The marsh meadow Calamagrostis angustifolia wetland is higher than the typical meadow Calamagrostis angustifolia wetland in both the content and variability of soil sulfur of various forms.In the two kinds of wetlands,all forms of sulfur displayed obvious characteristics of vertical distribution and variability.Content of organic matter in the soil is the important factor affecting the content of sulfur,which is also affected by contents of soils of various particle size fractions.Moreover,the contents of soil sulfur of various forms are also correlated with each other.

Bioturbation effect of benthic fish,e.g.Misgurnus anguillicaudatus,on nitrogen dynamic in paddy field surface water and its mechanism was investigated through a simulation experiment analyzing comparatively nitrogen contents in waters with and without Misgurnus anguillicaudatus.Misgurnus anguillicaudatus showed strong bioturbation effect.Throughout the experiment,NH⁺₄-N and NO^-₃-N concentrations remained higher in the bioturbation group than in the control group,while NO^-₂-N concentration did not show any obvious rules.In the early stage of the experiment NH⁺₄-N/TN ratio was higher in the bioturbation group than in the control group,while in the middle and late stages of the experiment it turned reversely.DIN/TN ratio was markedly higher in the bioturbation group than in the control group.Misgurnus anguillicaudatus bioturbation increased remarkably DIN and TN concentrations in paddy field surface water.

Investigations were carried out on activities of soil urease,sucrase and acidic phosphatease in soils under four different forest stands,i.e.Pinus massoniana,Phyllostachys pubescens,Quercus acutissima,and Cunninghamia lanceolata,and their relationships with soil physical and chemical properties in the south part of Jiangsu Province.Results indicate that the soil under Pinus massoniana is the highest in activity of sucrose and acidic phosphatease,the soil under Phyllostachys pubescens the highest in activity of urease,while the soil in bare land is the lowest in activity of all three enzymes.In soil profiles,enzyme activity declines gradually from top to bottom,and variation is obvious with soil sucrase and acidic phosphatase and not so with soil urease.The analysis of correlation indicates a significant positive correlation of soil sucrose and acidic phosphatease with soil total nitrogen,available phosphorus,and organic matter,separately,at the level of α=0.01,and with each other,at the same level,too;of soil sucrose with Pb at the level of α=0.05;of soil acidic phosphatease with Cu,and Pb at the level of α=0.01,of urease with Pb,soil total phosphorus and organic matter at the level of α=0.01 and with total N,acidic phosphatease and Cu at the level of α=0.05,but a significant negative correlation with soil bulk density.The regression analysis reveals that the three enzymes have a non-linear correlation with soil total nitrogen,available phosphorus,organic matter,Cu,and Pb.The principal component regression analysis indicates that the primary factors of soil fertility are soil total nitrogen,organic matter,available phosphorus,available K,urease,sucrase and acidic phosphatase.The three soil enzymes are the perfect indicators for soil quality assessment.

A field experiment designed to have four treatments,grass mulch(GC),film mulch(FM),bare(LL),and submerged(SZ),was conducted to study effects of rice cultivation pattern on yield and biomass of its after-crop,barley,soil microbial biomass and nitrogen fertilizer use efficiency.Results show that(1)Treatment GC was the highest in grain yield of barley,about 6.0%,16.4% and 37.0% higher than Treatments FM,LL and SZ,respectively;(2)Treatment GC was also the highest in biomass of the barley at its harvest stage,and about 3 424,6 059 and 6 961 kg·hm^-2 higher than Treatments FM,LL and SZ,respectively;(3)soil microbial biomass carbon and nitrogen increased first and then decreased with the growth of barley in all the four treatments,which appeared to be in a decreasing order of GC>FM>LL>SZ;and(4)Treatment GC was also the highest in nitrogen fertilizer use efficiency,and about 0.9,2.2 and 8.0 kg·kg^-1 higher than Treatments FM,LL and SZ,respectively,and a similar trend was observed of nitrogen production rate showing that Treatment GC was 2.8,7.0 and 13.3 kg·kg^-1 higher than Treatments FM,LL and SZ,respectively.The findings suggest that Treatment GC is an optimal cultivation pattern in rotation with barley.

Plastic mulching is widely used in commercial vegetable production in the world.The technique changes soil hydrothermal properties significantly and eventually bioavailability of heavy metals in the soil.Field experiments were conducted to study effect of plastic mulching on translocation characteristics of copper and zinc in the soil-Chinese cabbage(Brassica chinensis L.)system.Results show that plastic mulching promoted growth of cabbage,while changing physicochemical properties of the soil.Compared with un-mulched field,the mulched field was 12.77% and 33.90% lower in soil pH and SO2-4 contents,respectively,showing a significant level of difference(P<0.05).Plastic mulching didn’t have significant effect on the distribution and translocation characteristic of Cu,while it affected those of Zn.The concentration of each fraction of zinc extracted by BCR(community bureau of reference)three-stage sequential extraction procedure,in mulched field decreased by 25.87%,35.80% and 28.17%,respectively.The concentrations of Zn in Chinese cabbage in mulched field increased by 130.9% and 13.6% in root and leaf,respectively,but deceased by 23.7% in shoot.Plastic mulching activated Zn somewhat in the soil,releasing Zn,of which most was absorbed by Chinese cabbage root.So Zn absorption by Chinese cabbage root in mulched field was far larger than that in un-mulched field.

From the point of view of soil nutrient absorption capacity and crop demand for nutrients,evaluation of livestock manure assimilating capacity of the farmland soil-crop system was conducted with the aid of the spatial analysis and geostatistics techniques on a field basis in Daxing District of Beijing.Results show that the capacity of the farmland soil-crop system is not high on the whole in Daxing District,with 81.65% of the farmland being medium or low capacity,which,apart from the low nutrient holding capacity of the soil was,is related to the planting structure and planting area of Daxing District,especially the lower proportion of farmland and facility agricultural land high in soil fertility.

Concentrations of nutrient and toxic substances in livestock manure directly affect the value of its use.A total of 19 chicken manure samples were collected from intensive poultry farms in Zhejiang Province for characterizing contents of nutrient substances and pollutant elements,and chemical forms of P,Cu and Zn therein.Results show that the chicken manure contained high amounts of crude protein,minerals,Cu,Zn as well as dissolved salts.The elements of P,Cu and Zn in the manure were present mainly in extractable form,and hence high in bio-availability and mobility.The concentrations of trace elements and heavy metals in the chicken manure were obviously higher than those in the feedstuff that were fed,and affected by the latter.Significant correlations were found between concentration of Ca,Mg,P,K,As,Cd,Cr,Cu,Fe,Mn,Pb and Zn in the chicken manure and those in the feedstuff.Quality of feedstuff was an important factor controlling concentrations of heavy metals in chicken manure.

A fertilization experiment was carried out on two cropping of vegetables growing in simulated soil column.The experiment was designed to have 7 fertilization patterns [i.e.(1)CK or no fertilizer,(2)chemical fertilizer applied as basal dressing,(3)chemical fertilizer applied half as basal dressing and half as side-dressing,(4)chemical fertilizer and dicyandiamide applied as basal dressing,(5)chemical fertilizer and dicyandiamide applied half as basal dressing and half as side-dressing,(6)chemical fertilizer and organic manure(half and half on N basis),and(7)organic manure applied as basal dressing] to test effect of different fertilization patterns on yield and nitrate content of the vegetables,and loss of nitrogen and phosphorus from the simulated soil column.Results show that Pattern 4 and Pattern 7 not only produced higher yield of vegetables that were lower in nitrate content,but also significantly reduced leaching loss of nitrate-nitrogen,ammonia-nitrogen and water-soluble phosphorus from the soil column.Consequently,the findings can be used to effectively alleviate agricultural non-point source N and P pollution from vegetable fields to underground water bodies.

Effects of copper mine tailings from Tongling on growth,and physiological functions of Brassica campestris were studied by pot experiment.Results show that the seeds of B.campestris germinated on the tailings,but lower in percentage and rate than the control.Tailings decreased chlorophyll contents of the plants,chlorophyll a/b ratio is also affected.Nitrate reductase(NR)activity and ascorbic acids content of B.campestris decreased,but permeability of its cell membrane increased demonstrating toxicity of the tailings to the plant.Compared with those in the control,the plants in tailings were shorter in taproot,fewer in number of lateral roots and less in root volume.Tailings significantly affected root and shoot biomass and root/shoot ratio of its seedlings.The toxic effect of tailings became more remarkable with the growing plant,and was eventually reflected on the lower yield of the plant.The toxicity of copper and the extreme infertility of tailings were two major factors inhibiting growth of B.campestris.The distribution of copper in the plant at its maturing stage followed the order of root,stem and leave,seed.Significant positive correlation was observed between copper content in the seed and concentration of available copper in tailings.

In order to study bioremediation of petroleum contaminated soil,petroleum contaminated soils were collected from the Zhongyuan Oil Field and microorganisms that degradate petroleum were screened from the soil.Then,samples of contamination-free Fluvo-aquic soil were collected from the same area and mixed with 15 g·kg^-1 petroleum for pot experiment to study effects of the microorganisims and plants on remediation of the petroleum contaminated soil.The experiment was designed to have three treatments,(1)adding microorganisms,(2)growing plants,and(3)growing plants plus adding microorganisms.Results show that in Treatment 1,the degradation rate of petroleum was 67.0% after 120 days;in Treatment 2,it was 38.23%,36.57%,40.67% and 38.67%,respectively,with sunflower,cotton,bermuda grass,and sudan grass;and in Treatment 3(cotton + microorganisms)it reached as high as 85.67%.

Remediation of m-chloronitrobenzene(MCNB)-or m-nitrotoluene(MNT)-contaminated soils with zero-valent iron(ZVI)at ambient temperature and pressure was studied.Results show that ZVI efficiently reduced MCNB and MNT in soils into their respective anilines,without triggering any further dechlorination reaction or further demethylase reaction.The efficiency of reduction was significantly affected by reaction time,soil moisture content,initial soil pH,ZVI dosage and reaction temperature.When in the soil the concentration of the two pollutants were about 2.5×10^-6 mol·g-1,the moisture content 0.75 mL·g^-1,the initial pH 6.8 and the application rate of ZVI 25 mg·g^-1 soil,incubation at temperature(25±1)℃ for 5 hours,over 80% of both pollutants were reduced.Laboratory data also show that a longer reaction time,a lower acidity,a higher dosage of ZVI and a relatively higher temperature of reaction as well as a saturated moisture content may significantly increase the reduction rate.

Using bromine thymol blue(BTB)identifying medium and the conventional plating method,a strain of aerobic denitrifying bacteria was isolated from a sewage sample from an aeration tank of a Nanjing sewage treatment plant.The strain was named BMB-N6 and was identified as Alcaligenes denitrificans according to the 16S rDNA sequence homology comparison and phyletic evolution analysis.Its denitrifying capacity was determined in media different in nitrite concentration.Optimal denitrifying conditions were explored through orthogonal experiment.The denitrifying capacity of bacterial mixtures of strain BMB-N6 with protein degrading strain BMB-LA,and with ammonia degrading bacteria strain BMB-HKF were determined in both laboratory and field.The denitrifying rate of strain BMB-N6 may reach 94% within 8 h.The optimum denitrifying conditions are rotational speed 50 r·min^-1,C/N 4,pH 6,and 35 ℃.The denitrifying rate of the bacterial mixture may reach 90%(in laboratory within 12 h)and 80%(in field within 7 days).

Content levels of bisphenol A(BPA)in the surface waters of the Pearl River Estuary,Hengmen river and fishponds were determined by means of solid phase microextraction(SPME)and gas chromatography-mass spectra(GC-MS).Results show that the content of BPA in the three waters was 1.19,1.41 and 2.06 μg·L^-1,respectively.A significant relationship was observed between the contents of BPA and pH.According to the EC/PNEC evaluation system,the residual extent of BPA in the Pearl River Estuary area might not bring about any significant ecological risk to the environment and human beings.

Effects of pollution of the Grand Canal on activities of the superoxide dismatase(SOD),peroxidase(POD)and catalase(CAT)in the innards of Bellamya purificata in the Grand Canal,by means of indoor simulation,cage raising in sampled plots and direct sampling.Results show that activities of SOD,POD and CAT,components of the antioxidant defense system,in Bellamya purificata,are sensitive indicators of exposure to pollution.The monitoring findings tallied with the data of water chemical assessment.Within the range below the threshold,CAT activity decreased with the intensifying of pollution,while POD was activated,but amplitude of the rise varied from time to time.SOD fluctuated in activity,and is fit to serve as a short-term indicator.By comparing the three methods in determining effect of pollution on activities of SOD,POD and CAT in Bellamya purificata,the method of cage-raising is the optimal one,and the sampling method is not applicable.

A study was done on photic stability,photolytic dynamics and pathway of photolytic metabolism of olefin IMI.Results show that olefin IMI was stable in darkness.It decreased by 3% in concentration after having been kept in room temperature and darkness for 400 days.However in the laboratory under simulated sunlight,olefin IMI was unstable and easily degraded.Its photolytic reaction fitted the first-order kinetic equation(r>0.99),and its half life was figured out to be 4 days.Its photolytic reaction followed two pathways,either through hydroxylation into 4,5-dihydroxy IMI,which is oxidized,breaking its nitroimine pharmacophore and turned into carbonyl product,or through formation of guanidine metabolites by breaking off nitroimine group.

Comparison in bioaccumulation of trace elements between triangle-sail mussels(Hyriopsis cumingii)reared in aquicultural ponds in Gongan Country(APG)and in the Tongzhuanghe River,a natural waterbody,in the Three-Gorge Reservoir Region(NWTR),Hubei Province,China was conducted.The mussels in the latter were relocated from the former.After one year of husbandry,the mussels were sampled for analysis of K,Mg,Ca,Fe,Zn,Mn,Cu,As,Al,Cr,Ni,Se,Mo,Ag,Cd,Ti and Pb in their soft tissues,using an Inductively Coupled Plasma Mass Spectrometry.Although the 17 elements in these two groups of mussels followed a similar order in concentration,reflecting characteristics of bioaccumulation of the elements by the mussels,those in NWTR were higher than in APG in concentration of 9 elements(Ca,Mg,Cu,Mn,Zn,Cr,As,Cd and Pb),suggesting that living habitats may have an important impact on bioaccumulation in Hyriopsis cumingii.The mussels in the natural waterbody were exposed to a higher mean load of the elements in their soft tissues than those in the ponds,demonstrating the mussels’ significant capacity of sequestrating those pollutant elements and purifying waterbodies.The findings of the study may serve as scientific basis for rearing freshwater mussel to monitor pollutant elements in natural waterbodies and purify the environment therein.