A huge variety of Phytophagous insects live on Castanopsis sclerophylla leaves.In order to study relationship between insects and plants in island habitats,a survey was carried out of intensity and patterns of Castanopsis sclerophylla leaf eating by insects on several isles in the Qiandao Lake,Zhejiang Province.A total of 16 leaf-eating patterns were identified,varying in frequency.In terms of frequency and damage of leaves,edge defoliation,excavating defoliation,top defoliation,lower epidermis defoliation and middle vein defoliation were the most important types damaging leaves of Castanopsis sclerophylla.Results of correlation analysis show that among the 16 patterns significant positive correlations were found between six pairs.About 84% of the Castanopsis sclerophylla leaves were damaged as a result of leaf-eating by insects,but the damage mostly was not serious.

Farm belt in suburbs,as a kind of special agriculture area,has its own ecological benefit,which varies with land use patterns.With the aid of the GIS and SPSS techniques and mathematical models,a case study was conducted of Gaoping District,Nanchong City,Sichuan Province.Integrated ecological benefits of the district in 1996 and 2005 were evaluated and compared,using an ecological benefit evaluation system,composed of seven indexes,such as biological diversity,vegetation coverage,water and soil conservation effect,soil organic matter content,water-holding capacity,runoff interception rate,and air humidity.Results indicate that the integrated ecological benefit was 7.85 in 1996 and 7.95 in 2005;By making use of the analytic functions of GIS,like superposition and division,analysis was done of effect of change in land use on internal ecological benefit in the region.In terms of ecological benefits,Gaoping was divided into five zones: remarkably enhanced zone,enhanced zone,maintained zone,weakened zone,and significantly weakened zone.

A hydroponic experiment was carried out about cucumber seedlings of two different cultivars in salinity tolerance to explore the effects of exogenous spermidine on polyamine content and antioxidant system in roots of the seedlings under salinity stress.Results showed that under salinity stress,exogenous spermidine increased the contents of free spermidine and spermine,perchloric acid soluble conjugated(PS-conjugated) and perchloric acid insoluble conjugated(PIS-conjugated) putrescine,spermidine and spermine,and decreased the content of free putrescine in roots of cucumber.Besides,it also increased SOD,POD and CAT activities,decreased O₂^- production rate,H₂O₂ and MDA contents and electrolyte leakage,thus significantly promoting root growth.Furthermore,positive correlation was observed of the content of PIS-conjugated spermidine in seedlings roots with antioxidant enzyme activity.The findings suggest that high levels of free spermidine and spermine,PS-conjugated and PIS-conjugated polyamines,particularly PIS-conjugated spermidine,may enhance antioxidant enzyme activity,decrease O₂^- production rate and membrane damage,thus strengthening salinity tolerance of the plant.

Results of determination of soil moisture,soil temperature,and physiological characteristics of maize growing in plots different in mulching treatment showed that straw mulching could minish the range of variation of soil moisture and temperature in the surface soil layer of 0-10 cm;thus mitigating harm of drought on the crop.The thicker the straw mulching,the more significant the effect.But the effect was limited by soil aridness and growth stage of maize.For instance,at the elongation stage,straw mulching may maintain physiological activity of the crop and significant difference in this effect was observed between Treatment T3(15 t·hm^-2) and other treatments.But along with growth of the crop and increasing frequency of rainfall the difference gradually narrowed.At the milking and maturing stages,the effect was insignificant.Mulching may increase the yield of biomass and grains of the crop.In the experiment,Treatment T1(5 t·hm^-2) was the highest in grain yield whereas Treatment T3 in biomass production.The main reason for that was that the drought occurring at the elongation stage led to fast growth of the crop in Treatment T3,but didn′t affect much the physiological mechanism of the crop in Treatment T1 in the late growing period.

A stationary observation has been carried on for 8 years（1998—2005）,monitoring surface runoff in the field,and exploring characteristics and variation of surface runoff with time and land use.Results show that significant differences existed in surface runoff generated by rainwater between lands different in vegetation,following an order of crop land>orchard land>evergreen bush land>conifer forest land>disturbed restoration land>vegetation-restoring land.Surface runoff mainly occurred between April and August.Amount and intensity（2.58.0 mm·h^-1） of rainfall were the key factors affecting amount of surface runoff.Vegetation-restoring land and disturbed restoration land showed nice soil-water conservation efficiency and their cumulative runoff mounted up slowly.Soil-water conservation efficiency of forest ecosystems was closely related to the type of forest,following an order of orchard land>evergreen bush land>conifer forest land.As a result of frequently disturbance,the crop land suffered heavy soil loss with cumulative runoff mounting up quickly.It is,therefore,advisable that proper agro-forest ecosystems be established so as to further control soil erosion in South China.

Based on 48 years of summer rainfall data,Morlet wavelet analysis was done of the sequence of summer rainfall in Nenjiang and Harbin,on a multi-time scale.Results show that in recent years,the summer rainfall in Harbin displayed the most apparent cyclical variation on a 29-38-year scale,the largest modulus,and the strongest energy;and the summer rainfall in Nenjiang did an obvious cyclical variation on a 19-30-year scale,and its energy value is quite large.Both the two cyclical variations showed a trend of being stronger in energy with the time.Presently,both the summer rainfalls in Nenjiang and Harbin are in a long cyclical period of low-water.It is predicted that in a relatively long period the summer rainfall will be lower than the average of the past 48 years.

Aimed at the specific characteristics of agricultural non-point source pollution being difficult to monitor and control in irrigation areas,and based on the viewpoint of unit analysis,a concept of load contribution rate was put forward.On such a basis,a model was established for assessment of agricultural non-point source pollution load in irrigation areas.A case study of the Qingtongxia irrigation area was carried out making use of the quality monitoring data of irrigation and drainage waters in the irrigation year of 2005-2006.Annual mineralization degree and ammonia nitrogen,total nitrogen and total phosphorus loads of agricultural non-point source pollution were estimated by using the model.Comparison with the mean concentration method showed that the new method was more reasonable.The results show that the annual agricultural non-point source pollution in the Qingtongxia irrigation area outputted 283×104 t salt,0.55×104 t ammonia nitrogen,4.11×104 t total nitrogen,and 123 t total phosphorus.Compared against the water quality data of the control section of the Yellow River,the output of salt accounted for about 70% of the increment of salt in the mainstream of the river;and the load of ammonia nitrogen and total nitrogen was 0.28 and 1.52 times as much as the point source pollution load of the control section,which causes great impact on water quality of the trunk course of the Yellow River;however,the output of total P was quite limited and so was its impact.

An experiment was carried out on capacity of Lactobacillus brevis for removing nitrite from an aquacultural water body and its major affecting factors.Results show that Lactobacillus brevis is capable of efficiently removing nitrite in a water body complicated in water environment.It functions most efficiently when applied at a rate of ≤10 mg·L^-1 and when the water is >25 ℃ in temperature and ≤8.0 in pH,and ≤1.0 mg·L^-1 in nitrite concentration,and the effect is most significant within 48 hours.Besides living Lactobacillus brevis,its metabolites are also capable of removing nitrite.The research demonstrates that Lactobacillus brevis can be exploited as a potential product for bioremediation of aquacultural waterbody environment.

A static adsorption experiment on behavior of adsorption of sulfadiazine by montmorillonite and kaolinite was carried out to investigate influence of temperature,and pH on adsorption.Results show that the adsorption isotherms of sulfadiazine on montmorillonite and kaolinite were well described by the Freundlich and Langmuir equations,and the latter is better than the former in fitting.Kaolinite was higher in adsorption capacity than montmorillonite.Adsorption of sulfadiazine decreased with increasing temperature and peaked at pH 8.

A method has been developed for monitoring DA-6 in water using the solid phase extraction(SPE) method combined with gas chromatography.Three different SPE cartridges(C₁₈,florisil and Oasis^R HLB)were tested in extracting DA-6,showing a recovery rate of 8%,13% and 96%,respectively.The solid phase extraction method using an Oasis^R HLB cartridge was further studied for its optimal operating conditions,which were found to be 4-8 mL dichloromethane as eluting solvent;the reserved capacity of an Oasis^R HLB cartridge(60 mg) reaches as high as 200 μg·cartridge^-1.This method was applied to a photochemical degradation test of DA-6,with results showing that the photolysis of DA-6 in water followed the first order reaction,and its half-life was 82 min under xenon lamp.

Genotoxicity of ethylicin and bismerthiazol on Vicia faba root tip cells was studied.Micronucleus assay and chromosomal aberration assay were used to determine mitotic index,micronucleus frequency and chromosomal aberration frequency of Vicia faba root tip cells induced by different concentrations of ethylicin or bismerthiazol.Results show that both pesticides may induce high micronucleus frequency,mitotic index,and chromosomal aberration frequency.Micronucleus frequency increased with increasing of ethylicin concentration,and showed a linear dose-dependent manner in the treatment of ethylicin concentration ranging from 0.032 to 0.160 g·L^-1.However,it increased first and then decreased with increasing bismerthiazol concentration in the treatment of its concentration ranging from 0.625 to 2.5 g·L^-1.Different types of chromosomal aberration were induced by both ethylicin and bismerthiazol.

Samples of whole capsicum(Capsicum frutescens L.var.longum Bailey)plants and root soils were collected from capsicum fields in three villages in the suburbs of Guiyang,Southwest China to study characteristics of heavy metal transportation in the soil-capsicum system.Results show that the fields were polluted with heavy metals to a varying degree,with integrated pollution index being 1.17,1.23 and 2.18,respectively.Zn,Cd and Cu were the major pollutants.However,in the capsicum fruit only Cd was overproof.Transportation ability of the measured heavy metals follows a decreasing order of Cd Cu>Zn>Pb in the soil/root interface,Zn>Cd>Pb>Cu in the stem/root interface,and Cu Zn>Cd>Pb in the fruit/stem interface.And the soil/root interface was the main barrier for Cu,Pb and Zn to enter into capsicum fruit,and their bio-concentration factor(BCF) was in the range of 0.21～0.44,0.04～0.24,and 0.033～0.08,respectively.However,Cd accumulated in the root,with its BCF being in range of 1.06～4.23.Its translocation factors(TF1) demonstrated that there was almost no hindrance for it in the root/stem interface,but its TF2 being in the range of 0.42 and 0.51 revealed that its translocation was impeded in the stem/fruit interface.

Pak choi(Brassica chinensis L.)has been a major diet food in South China.Cd uptake by the plant and Cd concentration in edible leaves of the plant,effect of soil conditions,and plant cultivar,and their interaction are poorly understood.A pot experiment was conducted to explore Cd and Zn uptake during the whole growing period of the plant with and without Cd treatment.Two cultivars of pak choi,Siyueman and Gaogengbai,were grown in two soils(a Wushantu,Gleyic Stagnic Anthrosols and Hongshanitian,Ultic Stagnic Anthrosols) contrasting in soil chemical properties and soil total Cd and Zn contents.Cd was added at 0 mg·kg^-1 of soil(as the control) and 2 mg·kg^-1,respectively.Pak choi plants were harvested at different growth stages and biomass and Cd and Zn contents of different parts were determined.Uptake of Cd and Zn by the plant was significantly affected by soil type,plant cultivar,and soil Cd dosage,jointly.The studied two cultivars are different in Cd uptake with Siyueman being a cultivar of high Cd affinity and Gaogengbai of low affinity.Under a positive interaction of soil and cultivar,Cd uptake was enhanced by over ten times but Cd/Zn ratio in above ground parts of the plant did not follow the trend of Cd/Zn ratio in total uptake by the plant,for Cd and Zn distribution in different parts varied with cultivar as well as growing stage.The distribution coefficient was 56.3%-71.1% for Cd and 77.6%-80.6% for Zn.The decreased Cd/Zn ratio under Cd treatment resulted in a decreased Cd/Zn ratio in above ground parts,thus reducing the exposure risk;The dynamics of Cd and Zn uptake varied with growing stage and from cultivar to cultivar.Cd accumulated in the plant steadily with the growing period,while Zn uptake and accumulation turned slightly downwards after the seedling stage,thus leading to higher Cd/Zn ratio in the plant at the harvesting stage and higher risk of Cd exposure.This phenomenon was especially significant in the acid soil.

Effluent from anaerobic digestion was used in this experiment to ret rice straws.An orthogonal experiment program was carried out to determine effects of temperature,moisture,time and MLSS(mixed liquid suspended solid) on biogas generation during anaerobic digestion and compare retted rice straws with un-retted ones in biogas generation under different loadings of organic substances.Results show that the total biogas yield of retted rice straws was about 3%-49.5% higher than the untreated one.The optimal conditions for biogas generation were 30 ℃ in temperature,900 g·kg^-1 in moisture,10 days in time and MLSS at 1 500 mg·L^-1 in volume.Under such conditions,the biogas yield of retted rice straws reached 804.8 mL·g-1 VS(volatile solid),51.2% higher than that of untreated ones and the yield peaked 10 days earlier.

An experiment was conducted to investigate effects of exposure for 3 weeks to high concentration of Zn²⁺  (50 mg·L^-1) on immunochemical variation of serum and hepatopancreas in Procambarus clarkii.Antioxidative and immune parameters such as superoxide dismutase(SOD),lysozyme,acid phosphatase(ACP),and malondialdehyde(MDA) were measured.Results show that activities of SOD,ACP and lysozyme and content of MDA in serum all increased on Day 1,then turned downwards and decreased continuously with the prolonging of the exposure time,but the activities of SOD and ACP and the content of MDA were all only slightly inhibited after 21 days of exposure,but lysozyme remained higher in activity than that in the control groups.The activity of SOD in hepatopancreas was inhibited within 7 days of exposure and activated on Day 14(P<0.05),but suppressed slightly again after Day 21.Lysozyme and ACP both were activated first and inhibited later,but the inhibition effect was more significant in hepatopancreas than in serum after Day 21,indicating that hepatopancreas is more sensitive to Zn²⁺  than to serum,and Procambarus clarkii can tolerate high Zn²⁺  contamination by enhancing its immunochemical enzyme system.

N₂O emission fluxes were measured using the technique of closed opaque chamber and gas chromatography system,in a field experiment carried out during three growing seasons in 2003-2005 on a tract of Calamagrostis angustifolia meadow and Carex lasiocarpa marsh.Results show that the influence of wetland plants on N₂O emission of the wetland ecosystem varied with their growing stage.Obviously plants participated in and promoted N₂O emission in the wetland.The N₂O emission flux from the soil-plant system of Calamagrostis angustifolia meadow was 1.58,2.09 and 2.34 times as high as the apparent flux from the soil of the system during the three growing seasons,respectively,while that from the system of Carex lasiocarpa marsh was 1.86,1.50 and 1.33 times as high the apparent flux from the soil of the system.The N₂O emission flux of Calamagrostis angustifolia meadow was higher than that of Carex lasiocarpa marsh in all the three growing seasons,which may be attributed to differences between the systems in soil physico-chemical properties and hydrological conditions.

A GC method was used to determine degradation behavior and evaluate environmental safety of diquat in sugarcane and soils in Hunan and Hainan.Results show that the half-life of diquat in sugarcane and soil was 4.72 and 50.59 d,respectively,in Hunan,and 5.73 and 40.01 d,respectively,in Hainan.When diquat was applied at a recommended rate,residue of the effective component was much lower than 0.05 mg·kg-1,which ensures food safety of sugarcane.

The SCI-GROW model,developed by USEPA and commonly used in the United States,was selected to predict risks to groundwater of five types of pesticides frequently used in sugarcane fields in Fujian Province.Comparison between prediction and field measurement was carried out to validate the model.Results show that good correlation was observed between the two.The SCI-GROW model was applicable to screening assessment of groundwater contamination risks of pesticides in areas where groundwater is vulnerable to pesticide contamination in the coastal region of Southeast China with characteristics of higher in groundwater table,substantial in rainfall,and sandy in soil texture.In the end,the SCI-GROW model was used to predict risks of seventeen types of pesticides commonly used in the country,with a view to providing scientific reference for use of these pesticides.

A pot experiment was carried out to research effects of IFC,a fertilizer synergist,on pak choi.Results show that compared with application of carbon-ammonium fertilization only,the addition of IFC improved the growth of Brassica campestris ssp.Chinensis by increasing fresh yield by 8.97%(P<0.01),dry weight by 3.45%(P<0.05),and nitrogen accumulation by 8.70%(P<0.01),and decreasing NO^- ₃-N content by 30.10%(P<0.01),but did not have much effect on nitrogen content.The effect of IFC is much better than dicyandiamide(DCD),a commonly used N fertilizer synergist.Application of IFC at a proper rate can slightly accelerate ammonification and inhibit denitrification in the soil,and yet does not affect much microbial biomass in the soil.

Following the principles of ecosystems succession,an experiment was conducted in the acidic wasteland of Nanshan Iron Mining,Maanshan City,Anhui Province,on establishment of eight native species of trees,i.e.Cyclobalanopsis glauca,Castanopsis sclerophylla,Quercus fabri,Quercus acutissima,Quercus chenii,Ulmus parvifolia,Phoebe sheareri,and Machilus leptophylla.Three years after transplantation,Quercus chenii was found growing the fastest,reaching(194.89±2.71) cm in tallness,demonstrating a growth rate of 39.96 cm per year while Phoebe sheareri the slowest,being(72.67±2.91) cm with a growth rate of 20.89 cm per year.In terms of average ground diameter,Ulmus parvifolia ranked first,reaching(3.87±0.11) cm,whereas Phoebe sheareri last,being(1.27±0.15) cm.It is shown that these native species of trees can survive and grow up well in the acidic wasteland with some artificial assistance.In addition,broad-leaved deciduous trees are more adaptable to the experimental site than broad-leaved evergreen trees,and thought to be priority candidates to be used to restore native plant communities.

After defining of the concept of river health,and analysing of the characteristic indexes(ISC,RHP and USHA) of river health prevailing in other countries,attempts were made to assess river health in five different aspects,i.e.hydrology,morphology,riverside,physical and chemical properties of water quality,and aquatic life with an index system recommended to consist of 5 primary indices and 17 secondary indices.A data collection method taking into account reaches,measuring sites and transects was designed and a five-grade system including "excellent,good,marginal,poor,very poor" was established for assessment of river health.The above-described theories and methods were applied to the case study of a river in Shanghai,and the results reveal that this system is workable in assessing health or environmental conditions of rivers.

Canna indica growing in biological grid were analyzed for its growth and surface area distribution characteristics of its root system.A geometric calculation method was designed to calculate surface area of its root system by determining diameters of its second-class and third-class roots,separately.The result of the calculation by this method is 10 times as accurate as those by the common method,in which calculation is done based on root diameters regardless of root classes.The surface area of the canna roots is 39.4 m²,and the surface area of the third-class roots is 22.2 times as big as the second-class roots in the system.In the processes of eutrophication waterbody treatment by biological grid system the third-class roots play an important role in absorbing N and P,carrying microorganisms,enhancing adhering capacity of plant with fillers and improving the spatial structure of root system and filler