Some morphological characteristics of leaf and genetic structures of C.opulens populations which are found in Helinger(a semi-arid/partial humid region with lower temperature,lower light intensity and shorter sun time)and Alashan(an intensively droughty region with higher temperature,higher light intensity and longer sun time) were comparatively studied in this paper in order to understand the adaptation mechanism of the species to its habitat.The results indicated that leaf blade area,thickness,thickness/area,length/width,biomass and specific leaf area(SLA) of Alashan populations were different from Helinger population.Alashan populations were better in water protecting than Helinger population.As a result,they are better adaptation to arid environment than Helinger population.By comparing the genetic structures of the two populations,we can find that the genetic differentiation had occurred between Caragana opulens populations(genetic similarity coefficient was 0.711).This may indicate that the adaptation of Caragana opulens populations to its habitats take place at molecule level,and the population differentiation occur on the basis of genetic variability.

In order to study the dynamics of bird diversity in Nanshan mangroves,Guangzhou City,bird counts were conducted in January(winter),April(spring),July(summer) and October(autumn).The mangroves(Sonneratia.spp.) are dominant in this mangrove wetland.Based on the survey data,the indice of bird diversity were measured.The results showed the indice of diversity were 3.051,2.6314,2.6867 and 3.0382 in January,April,July and October which showed a clear seasonal variation in this wetland.Nanshan mangroves region plays an important role as bird breeding and wintering habitat in Guangzhou City.It indicates that restoration of mangroves is significant for conservation of bird diversity.

Diel vertical migration of Microcystis and crustacean zooplankton were investigated in October 2002.The results showed: Diel vertical migration of Microcystis(predominant Microcystis aeruginosa) was obvious.The daily density of Microcystis in the upper layer was higher than in the lower layer,the reversed pattern was observed at night.Chlorophyll-a(chl-a) had a similar pattern.Positive correlations(p<0.01) of Microcystis were observed with chl-a,water temperature,DO and pH.Diel vertical migration of several dominantly crustacean zooplanktons was surveyed.For Diaphanosoma brachyurum and Ceriodaphnia cornuta,higher density occurred daily in the lower water layer(1.5 m and 2.5 m),while they migrated to the upper layer(0 m and 0.5 m) at night.On the contrary,higher density of Chydorus ovalis appeared daily at 0 m and 0.5 m.The density of Bosmina at 11:00 and 15:00 at different water layers was higher than at night.Sinocalanus dorrii and Mesocyclops leuckarti were daily inclined to concentrate on the lower layers while they migrated to the upper layers.The density of Schmackeria sp.in different water layers at night and at 03:00 was greatly higher than other sampling times.Diel vertical migration of Limnoithona sinensis was not obvious.The negative correlation(p<0.01) between Microcystis and the density of D.brachyurum was observed,while it was positive with Bosmina and C.ovalis.

In this paper,the investigation of biodiversity of wetland Plant in China along South China Sea was conducted.The This region has a complex diversity of wetland habitats,wetland plant species and wetland ecosystem.There are 13 main types of wetland habitats,6 main types of wetland ecosystem,712 species of wetland advanced plants belonging to 158 families and 454 genera.Among these plants,there are 3 and 9 species belong to first-grade State protection and second-grade State protection respectively.

The effects of nitrogen(N) and phosphorus(P) limitation(N: 500μg·L^-1,P: 74～0.74μg·L^-1 and P: 74μg·L^-1,N: 500～5μg·L^-1) on the growth and cyst formation of Scrippsiella trochoidea(Stein) Loeblch III were studied by a series of indoor experiments.Results showed the specific growth rate was significantly low under limited nutrient condition,and effects of P limitation on growth were more obvious.The final cyst formation rates varied from 15% to 99%.Nitrogen depletion enhanced the cyst formation,and the highest encystment rate,nearly close to 100% under the condition of moderate N depletion.Generally,encystment occurred at the end of the exponential phase following the maximum numbers of vegetative cells.However,cysts were observed in the second day under low nutrient conditions,partly due to the sharp decrease of nutrient concentrations after inoculation.The present results suggested that cyst formation in the stationary stage reduce the cell number of S.trochoidea,which accelerate the dissipation of its bloom to some extent.

Investigation was carried out on osmotic permeability of biomembrane and antioxidization characteristics of asparagus under PEG stress with the concentrations of 10%,20% and 30%.The result showed that the contents of free Pro and soluble sucrose increased significantly with the test time,and reached the maximum at the treatment of 20% PEG-6000.The activities of CAT,POD and SOD increased with the concentration of PEG-6000,moreover,the relative conductivity and MDA increased with the test time and the concentrations of PEG-6000.This indicated that Asparagus officinlis seedlings adapted to drought stress by adjusting osmotic substance,decreasing water potential and improving protective enzymes activity to improve antioxydization ability under drought stress.

cDNA fragment encoding complete sequence of silver carp(Hypophthalmichthys molitrix) microcystin-deto-xifizyme was subcloned to construct a fusing gene expression vector pEGFP-N1-sGST,and a dicistronic expression vector pIRES2-EGFP-sGST.Using lipofectin method,the fusing gene expression vector pEGFP-N1-sGST was transfected into Hela cells.The emission of fluorescence was observed after 60 hours.Through microinjection,the dicistronic expression vector pIRES2-EGFP-sGST was delivered into embryos of zebrafish(Danio rerio),and the silver carp microcystin-detoxifizyme transgenic zebrafish was obtained.The success of the two transgenic models makes it possible to further analyze the cis-regulatory elements of the microcystin-detoxifizyme gene,and to develop a strain of transgenic planktivorous fish,used as a high-efficient biodetoxicator for microcystin in lakes and reservoirs.

The effects of three nitrogen sources(NaNO₃、NH₄Cl and NaNO₂) and different N/P ratios on the growth of Prorocentrum donghaiense were investigated.Results showed that all three nitrogen sources can be utilized by P.donghaiense.The optimum N/P ratio of P.donghaiense was 8 when NH₄Cl was the nitrogen source,and the growth was limited when N/P ratio was over 20.The optimum N/P ratio for NaNO₃ was 12,and the figure for NaNO₂ was 16.The results revealed that the optimum N/P ratio for all three N sources was between 8～20,and relatively higher N/P ratio(32 and 100) would limit the growth of the algae.

Effects of high light(HL) acclimation and low light(LL) acclimation on photosynthesis of Chlorella pyrenoidosa were investigated by measuring rapid light curves with Pulse-Amplitude Modulation Fluorometer.After LL acclimation,α increased while I_k decreased,which indicated the light-harvesting rate increased after LL acclimation.After HL acclimation,P_m increased while β decreased,which suggested maximal photosynthetic rate and high light tolerance can be improved after HL acclimation.

The effects of climate change on winter wheat and spring wheat of China were analyzed by using the stochastic weather generator which combinded the CERES-wheat model with the climate change scenarios predicted by the climate model with the amount of CO₂ increased.Then control water the wheat under A2、B2 climate change scenario,with the heat and CO₂ effect,were simulated respectively.The results indicate that the growing season of wheat is shortened because of climate change,.The stages of Winter wheat were more shorten than Spring wheat.In ten sites of North China,different areas and climate conditions will have different optimum water conditions.Variation scope of optimum water conditions is 40%~80%.Without the effects of CO₂,wheat yield will increase under optimum water condition in the future.With CO₂ effects,wheat yield has extensive increase.

The growth of Phaeocystis Globosa,total phosphorus in water,alkaline phosphatase activity in P.globosa cells were measured under different phosphorus conditions.When phosphorus deficiency and large molecular DOP(Lecithin)used in this experiment,alkaline phosphatase activity in P.globosa cells increased to 19.11U and 18.28U respectively,and both of them peaked at day 9.Results showed alkaline phosphatase played an important role in phosphorus deficiency stress and the utilization of large molecular of DOP.DIP(KH₂PO₄)and small molecular DOP(Natrium-β-glycerophosphat)can be easily utilized by P.globosa,whereas alkaline phosphatase activity did not changed significantly.

Microcystis is a freshwater harm algal bloom species,and its taxonomy is difficult to be identified with traditional approach.16S rRNA has been successfully applied to identify this microorganism species.In this study,partial sequences of 16srRNA gene of three strains of M.flos-aquae from 3 reservoirs in Guangdong Province were determined.Clustal1.83 and MEGA3 software package was used to analyze their genetic characteristics.It showed that alignment of the 3 sequences totaled 1035bp without any indels,and nucleotide similarity were above 99.85%,which suggested that discrimination of the 3 strains was failed,and 16S rDNA sequences were quite conservative within species.The degree of nucleotide dissimilarity among endemic Microcystis species are yet to be determined.In order to identify Microcystis species from reservoirs in Guangdong Province,more strains of various morphology and origins should be analyzed to build nucleotide database of sequences of 16s rRNA and other gene,so that difference within and among species could be found and species-specific probes could be designed.

In this paper,acute-toxicity test using zebrafish was applied to monitoring the wastewater form six industries.Based on 96h LC₅₀ values,the toxicity sequence of the six industrial effluents was in order of electron effluent>grocery effluents>electroplate effluent>battery effulent>glass effluent>rubber effluent.The six 96hLC₅₀ are as follows:0.98%、4.73%、11.35%、13.60%、47.60%.The toxicity of the rubber effluent was the least,the 100% industrial wastewater can not be deadly to Brachydanio rerio fish.The toxicity was eliminated after management,but the toxicity of some industries were not eliminated.

The sinking and floatation of fertilized eggs and the hatching rates and abnormal rates of eight broods of fertilized eggs under different salinities(20,23,26,29,32,35,38,41 and 44)were observed and compared,and the SAI(survival activity index)values of larvae were evaluated under different salinities(10、14、18、22、26、30、34、38、42和44)for cobia.The results showed that the fertilized eggs entirely sank in the seawater with salinity lower than 26,and entirely floated in the seawater with salinity higher than 32.The suitable salinity for hatching was from 26 to 41 and the optimum was from 29 to 38.The ranges of 23~26 and 41~44 might be two critical salinity causing notable differences in hatching rate of fertilized eggs and abnormal rate of newly hatching larvae.The SAI values of cobia larvae in different salinities were 2.32~16.24.The suitable salinity range for larvae survival activity was 22~38 and the optimum was 26~34 according to SAI values.The salinities from 18 to 22 and from 38 to 41 might be two critical ranges causing notable differences in SAI values.

The water environment of Lake Donghu,Wuhan,is polluted heavily as a result of population growth and economy development,and the problem of eutrophication is serious.The remedy of Lake Donghu was more and more enhanced from 1980',and the remedy has taken effect by filter-feeding fish.In this study,the time series models and regressive analysis of SPSS were applied to analysis the long-term change of fish yield;the highest fish yield was between 1700t and 1850t in Lake Donghu,and the reasonable fish yield should be about 1150t.

The uptake and distribution of ¹²⁵I and ⁶⁵Zn in toad Bufo bufo by different ways were studied.Results showed that the retention dynamics of ¹²⁵I in toad,whether injection or oral administration,had little differences.Both of them composed of a quick elimination stage and followed by a platform stage.During the quick elimination stage(0-2d),the radioactivity decreased significantly.Then the retention rate of ¹²⁵I in toad was maintained about 8% during the following experiment.After injected with ⁶⁵Zn,the retention rate was between 102.4%-114.48%,implying that almost all of ⁶⁵Zn remained in the body,the loss of Zn was not significantly.However,by oral administration,the retention dynamics of ⁶⁵Zn was significantly different from the injection group.The retention rate decreased slowly during the experiment.

320 topsoil samples(0~10cm)were collected from five different land-use sites(i.e.industrial areas,roadsides,agricultural areas,residential areas and parks)in Xigu District of Lanzhou city,northwest China.Physical-chemical properties and contents of Pb、Zn、Cu、Cd and Hg in these samples were analyzed to examine the effects of the different land-use types on quality of urban soils.The results showed that(1)soil samples from the industrial areas had the lowest pH but the highest electric conductivity among the five sites;(2)the contents of organic carbon in the roadside soil samples were significantly higher than those in the agricultural,residential and park soils;(3)the contents of Pb,Zn,Cu,Cd and Hg varied significantly between the five sites but were consistently higher than the background values of local soils;and(4)the calculated Nemerow integrated pollution indices were 4.9,3.7,4.0,2.4 and 2.2 for the industrial areas,roadsides,agricultural areas,residential areas and parks,respectively.This study suggests the differential effects of the five different land-use types on the physical-chemical properties and accumulation of heavy metals in urban soils,with the strongest influence by industrial activities,followed by traffic activities,agricultural activities and inhabitant living activities.

The structure and function of wetland ecosystem in Sanjiangyuan region are analyzed based on investigation data.The results indicate that the value of wetlands ecosystem is 2.10×10¹¹ YuanRMB·a^-1 and is 62.07% of the total value of ecosystem of Sanjiangyuan region.The value of waste treatment,water conservation and climate regulation is 6.40×10¹⁰ YuanRMB·a^-1、5.79×10¹⁰ YuanRMB·a^-1 and 4.90×10¹⁰ YuanRMB·a^-1,respectively and accounts for 30.55%、27.61% and 23.39% of the total value of wetlands ecosystem,respectively.There are some other services such as biological diversity,soil formation and erosion control,gas regulation,food and raw materials,recreation and culture.In addition,Measures on reasonable utilization and conservation are put forward on the basis of degradation mechanism and problem of wetlands ecosystem in Sanjiangyuan region.

Preferential flow is common phenomena in soil,and has significant influence to soil water movement.The soil preferential flow under three typical vegetations was researched by using brilliant blue dye tracer method in field,in order to research the forest conserving water resources deeply.The results showed that the preferential flow exist in all soils under three typical vegetation in upper reach of Minjiang River,and the complex degrees of preferential flow is different for each soil due the deference of vegetations,elevations,soil formation processes,action of roots and soil animals.The dye area ratios reflected the distribution of infiltrated water in soil profiles,although most infiltrated water rested within 10 cm nearly soil surface,some water reached the bottom of profiles through the preferential flow channels.The fractals of preferential flow dye profiles were 1.59 to 1.85,and it reflected the complexity of preferential flow channels,the soils under the virgin coniferous fir forest and sub-alpine meadow had high fractals with complex preferential flow channels.The preferential flow brings key influences for knowing hydraulic processes in slope,and is a basis for understanding the hydraulic effects of forest.

A pilot experiment was conducted to compare the removal rate of pollutants,plant growth and biomass of species in gravel-bed subsurface flow constructed wetland and soil-bed surface flow constructed wetland treated with larger water load.The results showed that the wastewater purification effect in subsurface flow constructed wetland was superior to that in surface flow constructed wetland with the same retention time.Root biomass in surface flow constructed wetland was significantly higher than that in subsurface flow constructed wetland,while the shoot growth in surface flow constructed wetland was nearly equal to that in subsurface flow constructed wetland.The results suggested that there wasn't correlative relaxation between purification effect and root biomass.

Based on the material balance theory,the quantitative relation has been established among substance endogenous load of nitrogen and phosphorus,their quantity of input and output of the reservoir,and the storage quantity in the water body.Take Dongzhang Reservoir of Fujian Province as an example,the quantitative analysis of the endogenous load of nitrogen and phosphorus in a reservoir was carried out,and its temporal distribution law was revealed.Furthermore,this paper expounds the method and procedure of how to reckon the endogenous load of nitrogen and phosphorus in the reservoir month by month according to the surveyed statistical data of water quality and hydrology.The research tells us that the distribution of endogenous load of nitrogen and phosphorus is subject to seasonal change and the level of endogenous load is somewhat concerned with dissolved oxygen in the water bottom.From January to April,it is oxygen-enriched in the water bottom,therefore,the input of endogenous of nitrogen outweighs the output and the load appears positive;in other months,it appears negative.In July and August,it is anaerobic in the water bottom,therefore,the input of endogenous phosphorus of outweighs the output and the load appears positive:in other months,it appears negative.This approach of analysis proves to be quite accurate with abundant and precise data on the input and output of pollutants,the inspection information of the accumulation of water pollutants and other concerned hydrologic information.

Biodiversity of Hunan province is simply assessed by the ways of market price,shadow price,production cost,shadow engineering and journey cost.It offered a set of reference way of quantification assessment for green GDP business accounting,construction program of ecologic city and ecologic county,and related environment impact assessment.This article emphasizes on the account of direct usevalue and indirect usevalue.The assessment conclusion shows that:in 2000,the direct usevalue of biodiviersity of Hunan province is 202.24×10⁹ Yuan,indirect usevalue is 1 682.68×10⁹ Yuan,potential usevalue is 25.0×10⁹ Yuan,which occupied 10.6%,88.1% and 1.3% of total economic value respectively.In 2000,the total economic value of biodiversity of Hunan province is 1 909.92×10⁹ Yuan,which occupied 4.9% of China,which is 5.17 times of GDP of Hunan province in 2000.

Soil microbiological analyses may serve as a means for assessing soil characteristics.Standard microbiological culture-techniques,however,leave over 90% of the microorganisms in the environment unaccounted for.Several more recently developed analytical techniques such as phospholipid fatty acids(PLFA),BIOLOG microplates,and molecular techniques allow for more detailed analyses of soil microbial communities.Each of these methods analyzes a different aspect of soil microbial characteristics.This review provides an outline of the main methods used in soil microbial ecology.

The negative effects of agrochemicals on ecological environment were briefly introduced,and the quantity of agrochemicals used in Liaoning Province in the recent years also were analyzed in this studied.Research results showed that the amount of chemical fertilizer used per hectare of all cities in Liaoning Province were higher than national average level,and exceeded security upper limit which constituted by developed countries.The quantity of pesticide used in four cities was aslo higher than national average level.Amount of plastic for farm use in Liaoning Province is large and place in a competition before the forth in the range of whole country.

The urban forest has important significance in economical ecology for urban agglomeration development in the Pearl River Delta.Although obtaining great achievements in construction of urban forest last decade,there are still some problems in this region,such as non-connective forest network,lower forest cover rate,lower "green vegetation accumulation" and unreasonable forest type and so on.The construction of urban forest in this region should serve the needs of ecological cities and forest ecological circle of the Pearl River Delta,embody the innovatory reformation and focus on forest network for allover the region.Some effective measures for construction of urban forest in this region were suggested,including erecting the forest ecological corridors across the region,attaching importance to the function of region-specific constructive tree species,introducing the new conception of networking forest and water timely,and paying attention to the forest ecological construction of urban residential quarters.The purpose of this article is to promote the construction of the urban forest and its sustainable development in the Pearl River Delta.