Mangroves are vulnerable habitats to pollution and accumulation of polycyclic aromatic hydrocarbons (PAHs).Many studies have reported the aerobic biochemical pathways of PAH degradation by bacteria and fungi but little is known about the anaerobic ones.In this paper,naphthalene was used as a model compound for PAHs demonstrating the possible anaerobic degradation pathways in mangrove environments.Oxidation of naphthalene was firstly found under anaerobic conditions in sediment columns and subsequently under strict anaerobic conditions and the processes were proved to be sulfate-reducing dependent by testing with sodium molybdate,a specific inhibitor of sulfate reduction.Further detailed studies isolated and identified several intermediates such as 2-naphthoate,5,6,7,8-tetrahydro-2-NA and decalin-2-carboxylate during the transformation processes of naphthalene.In these studies,different initial steps (hydroxylation or carboxylation) were proposed for naphthalene degradation.However,specific transformation steps for naphthalene will need further investigation to elucidate if degradation pathway of benzoate is involved.

Micioalgal photosynthetic hydrogen production is an effective way to solve our energy crisis.This review summarized the mechanism of microalgal photosynthetic hydrogen production,including hydrogen production catalysed by nitrogenase and reversible hydrogenase in cyanobacteria,and also by reversible hydrogenase in green algae.Based on analysis of the limiting fators of photosynthetic hydrogen production,both the classical mutagenesis/screen approach and the molecular biology approach were recommended to improve the hydrogen production rate.Hydrogen production by nitrogenase,direct biophotolysis and indirect biophotolysis were compared to show indirect biophotolysis by green algae have the greatest potential for future applied R&D.The prospects of microalgal photosynthetic hydrogen production were discussed.

Methyl tert-butyl ether (MTBE) is the most commonly used gasoline oxygenate in the North American's fuel industry.Due to its high solubility in water and low sorption tendency in soils,MTBE has become one of the most common contaminants in urban ground water.This paper examined the potential for phytoremediation of MTBE within a carefully designed bioreactor.Pre-rooted willow trees (Salix alba) were kept in an Erlenmeyer flask of 500 mL with 450 mL spiked aqueous solution for 12 d.MTBE and the main metabolite TBA were measured by GC/FID.Willow tree uptake tests indicated that the removal of MTBE mass in aqueous solution through willow tree activities was found in the range of 24.84~53.27% at 15·~25·over a 12-day period of exposure.The fraction of MTBE (%) removed from the aqueous solution by willow trees was positively correlated to tree transpiration (mg).Neither TBA,nor any other possible metabolite of MTBE was tracked in this test,indicating phytovolatilization is the dominant mechanism for phytoremediation of MTBE.Results of the bench-scale studies indicated that a large fraction of MTBE was released into the air without any conversion through willow trees over a short period of time,however MTBE will be susceptible to photooxidation and does not become an air quality concern.Therefore,it is to conclude that phytoremediation is an effective method to clean the soil and groundwater contaminated with MTBE.

To further resolve the phylogenetic affinities of Cercidiphyllaceae,matK gene sequences generated for Tetracentraceae,Daphniphyllaceae,Cercidiphyllaceae and Liquidambar,Rhodoleia and Hamamelis of Hamamelidaceae,were analyzed using Neighbor-Joining method with Magnolia as an outgroup.The matK consensus tree displays similar topology to those of rbcL,atpB,and 18S rDNA sequences analyses respectively and combined with greater phylogenetic resolution.It shows that Cercidiphyllaceae,Daphniphylliaceae and Hamamelidaceae formed a robust clade,but relationships among them are not resolved;the phylogenetic relationships of Tetracentraceae to Cercidiphyllaceae are not so closed as traditional treatment.Thus,several lines of evidence,derived from both the chloroplast genome and 18S rDNA sequences,suggest the presence of considerably phylogenetic affinities between Cercidiphyllaceae,Daphniphyllaceae,and Hamamelidaceae,further information on some other quickly-evolved genes are needed to resolve phylogenetic relationships among them.The study corroborates the idea that matK sequences have potential in resolving phytogeny at family level.

Wavelet Analysis is a new technique which developing quickly in time-frequency analysis.Because of its characteristics of multiple timescales,multiple layers and multiple resolutions,wavelet analysis has been applied widely in signal analysis,information analysis and earth sciences,etc.In this paper,wavelet technique was used to analyze phytoplankton variation for the first time on the basis of two 30-day in situ observations which carried out in spring and autumn 2002,at the fish-farming area of Dapang'Ao Cove,Daya Bay.Results showed that,the wavelet transform of spring and autumn phytoplankton density time series have characteristics of dominance periods and multiple timescales,which consistent on large scale but differential on small scale.And the analysis results of different wavelet transforms (such as Mexh wavelet transform and Morlet wavelet transform) have some different characteristics.The preliminary application of wavelet analysis technique in ecological study on coastal waters shows that,wavelet analysis technique can be applied to analyze the dynamic variation of phytoplankton in ecosystem on multiple timescales,multiple layers and multiple resolutions,and provids a new method for further studying and forecasting phytoplankton dynamics.

To get the optial amplification conditions for Alsophila spinulosa,the effects of the purified methods of DNA templates and the concentrations of DNA templates,Taq DNA polymerase,magesium,primer and dNTP are tested.The results suggest:the purified templates by glass milk or proteinase K are brighter,clearer and more repeatable than the unpurified templates or precipitated templates by ethanol;the concentration of DNA templates,Taq DNA polymerase,magesium,primer and dNTP will influence the productions of RAPD.The optimal amplification conditions for Alsphila spinulosa is acquired through the experiments:the concentration of DNA templates is 70ng,the concentration of magnesium is 2.5 mmol·L^-1,dNTP is 0.2 mmol·L^-1,primer is 3×10⁴ mL.The optical amplification program is also obtained:94·200s,1 cycle;94℃ 60s,36℃ 60s;72℃ 120s,40 cycle;72℃ 600s,1 cycle;stored in 4℃.

The change in the constitution of Macrobrachium rosenbergii hemocytes was observerd and the functions of different type hemocytes were speculated after PSB into the muscle of Macrobrachium rosenbergii as a exciter.Stained by Wright's staining,the staining slides were observed under the light microscope at 12,24,36,48,60 hours after received injections.It shows that hyaline cells normally constituted 66.62% of the total amount of hemocytes.In 24 hours after received injection,the ratio of hyaline cells to the total amount of hemocytes became to about 60%,after 36 hours,it declined sharply to nearly 30%,after 48 hours,it began to rise,and after 60 hours it recovered to 55%.The process of change is that the ratio declined slowly at first,then to declined sharply,and to recovered later.

The experiment was carried out to test the oxidation effect of phenol by potassium ferrate (K₂FeO₄) which synthesized by using hypochlorite oxidation method,then studies the effect factors was analy sed.The result indicated that,the rate of potassium ferrate removing phonel depends on the ratio of K₂FeO₄ phonel and this oxidization treatment showed a better effect under acid condition.This reaction mainly ocrred within a few minutes,then slows down.

The morphology and the classification of haemocytes are the foundations of the immune system studies in Crustracean.Dyeing results of Giemsa,Wright's,Wright's-Giemsa by different staining protocols were studied.Using different concentrations and dosages of dyes,we compared the dyeing results of haemocytes with different staining time,staining temperature,decoloration time and methods.The appropriate protocols of three staining methods were determined according to the dyeing results of granules,nuclei and cytoplasms.

Effects of several treatments in shrimp pond effluents was studied.Phosphate,total phosphorous,phytoplankton,zooplankton and bacteria,dissolved chemical oxygen demand,paniculate chemical oxygen demand,and total chemical oxygen demand were measured under five treatments,in which four biofilters were mussels Pernav Viridis,red algae Gracilaria tenuistipitata var.Liui Zhang et Xia,bacteria and mixture of these three organisms above,respectively,and the fifth one was the self~purify treatment.The results showed that 1) there were differences among the trends of fluctuation in these nutrient content,and interrelations among some nutrients were observed,2) the concentration of dissolvable nitrogen and the size of bacteria population decreased by all treatments,3) contents of COD can not be removed,but the forms of COD were transformed,4) mussel removed phytoplankton obviously.

Biomass and contents of protein,âcarotene and soluble carbohydrate of Dunaliella salina under Oìg·L,3 ìg·L^-1,12 ìg·L^-1,50 ìg·L^-1,200 ìg·L^-1 and 800 ìg·L^-1 of Cr³⁺ concentration were analysed.The results snowed that the lower level of Cr³⁺ could promote the growth of algae.When D.salina exposed to 50 and 200 ìg·L^-1 of Cr³⁺ the algae contained protein 3.06% and 6.55% higher than the control respectively,and had higher biomass.The algae in the medium added 200 ìg·L^-1 of Cr³⁺ resulted in âcarotene and soluble carbohydrate contents of 3.93% and 2.38% higher than the control respectively.In a conclusion a suitable dose of Cr³⁺ in medium stimulated Dunaliella salina to grow and improved the quality of nutrient such as protein,âcarotene and soluble carbohydrate.

This paper has investigated and studied the plant species of green land in Xiaolan Town,Zhongshan City.According to the survey,garden plants in Xiaolan town are abundant and varied including 105 families and 433 species,most of which are planted in parks and nurseries.In contrast,there are much fewer street trees and road trees.Arbors and shrubberies are widely cultivated,especially efflorescent arbors are extensively planted in parks,while lianas are rarely used.Aspect and type of the artificial forest are very monotonous.There is a serious lack of green land in the old urban area.Some factories and schools do not attach importance to greening.The author points out that garden trees should be reasonably chosen,and indigenes mainly planted,such as Magnoliaceae,and in the meantime exotic species introduced,such as Bignonaceae,Bombacaceae and Fabales.The residual forest of Eucalyptus and Acacia in Yuanlan Hill should be improved by building the mingled forest,in which main trees selected from Lauraceae,Fagaceae and Theaceae will be planted together by stages and in batches.In the end,garden plants suitable for different types of green land are picked out.

To determine the requirement dose of lysine during stages of growth of Ctenopharyngodon idellus,the growth rates of fingerling grass carp which fed in different levels of lysine were tested.In addition,the free lysine levels of serum,liver and muscle of fingerling grass carp were detected.The results showed that the requirement dose of lysine in feedstuff was 1.61% which was determined by the results of the maximum of growth rates,and the requirement dose of lysine in feedstuff were 1.28%,1.46% and 1.49% which were determined by the results of free lysine levels of serum,liver and muscle respectively.The requirement dose of lysine in feedstuff which was determined by the results of free lysine levels of serum was lower than that the results of growth rates,while the requirement doses of lysine in feedstuff which were determined by the results of free lysine levels of liver and muscle were close to the results of growth rates.

Long-term continuous two-crop winter wheat and summer corn rotation with no-tillage,direct drilling and conventional tillage affected the structure and numbers of the microbial flora for nitrogen transferous bacteria in soils.In the layers of 0~0.1m and 0.1~0.2m soils,the numbers of anaerobic dinitrogen fixed bacteria in no-tillage were increased remarkably,and aerobic dinitrogen fixed bacteria in no-tillage and conventional tillage were also increased compared to other tillage treatment.The numbers of denitrifying bacteria were decreased and differed insignificantly in the surface soil layer for the three tillage methods,but conventional tillage had more and direct drilling less denitrifying bacterial numbers in the 0.1~0.2m and 0.2~0.3m soil layer.Ammonia oxidizing bacteria fluctuated largely,and no-tillage soil had more numbers.Nitrite oxidizing bacteria were increased in no-tillage soils in 0~0.1m soil layer,but in 0.1~0.2m soil layer it were more in no-tillage and conventional tillage soils.

The coastal zone of Guangzhou city,located beside the Zhujiang River estuary,is a kind of silt flood plain.There are wide beach,many kinds of wetlands,and rich wild lives in the coastal zone.Based on the study,it was found that the ecological environment of the zone had been significantly changed since the reform and open of China.Serious ecological problems created such as lost of natural wetlands or the transformation from natural wetlands to controlled wetlands,pollution of water,decline of plant and animal sources,biological invasion of exotic species,more often of flood disasters,et al.As a result,the coastal zone became more fragility.The problems was mainly caused by the development of the coastal zone such as enclosing tideland for cultivation.According to the spatial development tactics of ‘extend toward south' of Guangzhou city,more powerful development of the coastal zone will be operated.It is crucial to protect the ecological environment in spite of the government has pay much attention to sea protection,restoration of mangrove wetland,and establishment of reserves.

Based on the comparative plots monitoring method,the characteristics of forest communities before and after rehabilitation in Shunde of Guangdong Province have been investigated.The main forest types in Shunde were Pinus elliottii,Eucalyptus exserta,and Acacia confuse plantations and were singularity in species composition and low biodiversity indexes before rehabilitation as well as the simple structure.After rehabilitation,the biodiversity index (Shannon-Weiner index) can be increased from 1.6 to 3.7 (calculated by species) or from 2.1 to 4.0 (calculated by important value of species).The tree DBH and Height class curves are becoming "reverse-J" type which is in good status of the forest structure and is favor of the community succession.The suggestion of the forest rehabilitation is to select the endemic broad-leaved species,to remain some tree-layer individuals (about 0.3 of the canopy density) and to remove them gradually in the next 2-5 years along with the endemic species growing.

Marine algae are numerous,and often difficult to be identified and classified based on traditional taxonomy due to variable morphological characters and complicated life histories.The development and application of molecular markers make DNA to be a useful tool to differentiate different species and have successfully determined the species identities of many problematic taxa.1733bp nucleotides of 18s rDNA from a marine algae ST3 were determined in this study.The sequences were then used as molecular criteria to investigate the algae identities and their classification.The result showed that ST3 belonged to Thalassiosirales,Bacillariophyta,although ST3 was more closely related to Skeletonema than did Thalassioria,considerable genetic distance between ST3 and Skeletonema existed,so ST3 might be a new genus in Thalassiora.18s rDNA was useful to identify and classify marine algae.

It is shown by the results of analyzing investigating and field detected data that the impact scope of Zhanjiang thermal power plant to the aquatic ecosystem in Maxiehai canal is mainly limited within the narrow area with 2℃ temperature increases,which is close to the drainage outlet.The impact of water temperature increase caused by the warm water drainage from the plant to plankton and fish behaves as the decreases of kinds and quantity within the high temperature increase area in summer,and litde influence to fishery production and ocean microbes.But the process of water intake to the plant may form punching and ramming harms to big aquatic organisms and fishes.

The design and operation of oxidation ditch process to treat domestic sewage are summarized and discussed.When the levels of COD and BOD in the influent were <400 mg·L^-1 and <200 mg·L^-1,the removing efficiencies for COD and BOD were >80% and >85%,respectively.It is confirmed that this process might be a high effective one with advantage of low investment,stable operation and well-treated effluent.

The paper reviewed advance and future direction of eco-toxicology of Polychlorinated biphenyls,discussed detailed the resource,distribution,transferring of Polychlorinated biphenyls,especially paying more attentions to the possibility of effects of Polychlorinated biphenyls upon the human being due to their bio-accumulation,bio-concentration and bio-magnification through the trophic relation like food webs in ecology system.

Methyl tert-butyl ether is a widely used gasoline additive.Its presence in the environment causes a widespread pollution and poses a serious threat to human health.Current literature on the treatments of methyl tert-butyl ether contamination,including advanced oxidation processes and microbial biodegradation,is reviewed.The advanced oxidation technologies include heterogeneous photocatalytic oxidation,UV/H₂O₂ oxidation,conventional ozonation and ozone/hydrogen peroxide,ultrasound irradiation and sonolytic degradation in the presence of ozone,Fenton's reagent and UV-assisted Fenton's reagent,reductive activation of dioxygen as well as r radiolysis of H₂O.Microbial biodegradation of MTBE involves both the aerobic and anaerobic metabolism.

Eco-travel is a spirit travel and culture travel at high level.It became popular in recent years.As a new-born area,it has different identification and many debates at the beginning.However,people understand,enrich and develop the inner meaning of eco-travel through practice,and then form a common sense which in turn contribute to the sustainable development of eco-travel.The nature and characteristic of eco-travel were clarified based on the ecology.The interaction between ecology and travel were analysised in this article.The purpose of these article is to let people recognize nature,return to nature and enjoy nature,thus could encourage the co-development for ecological environment conservation and social culture as well as economy.

210 species of birds are observated in Yalu River Nature Reserve,only few nature habitat occupied by Saunder's Gull survived in the core of the region,now a serious question about habitat fragmentalization still continued.So it is essential for habitat restoration,ecological management and consideration given to both construction and development.according to the principles and mothods of landscape ecology,restoration ecology,conservation biology,and by the sustainable development.In the near future,much more birds may in be breed,winter migrating in or through Yalu River Wetlands.

Due to their high implementing costs,strict technical demands and probably serious damage on soil texture,conventional ways are difficult to be selected for contaminated soil remediation on a large scale.Bioremediation technique has been proved to be an extensive prospect for use in contaminated soil remediation and becomes a research focus in the field.In the paper,the mechanisms and research advances in bioremediation on the organic and heavy metal contaminated soils were reviewed.And the latest development,disadvantages and trends of the bioremediation technique were also preliminarily discussed.