The Lingding Bay,an important area for fishery resources,has endured the deterioration of ecological environment due to human activities.In order to understand the influence of deteriorative environment on the fisheries,seasonal variations of nekton were studied based on the data from four cruises conducted from August 2009 to April 2010 in the Lingding Bay of Pearl River Estuary.A total of 92 species was identified,including 54 species of fishes,32 crustaceans and 6 cephalopods.The species richness was recorded with a maximum in summer and a minimum in winter.The species number of nekton alternated significantly from spring to summer and from winter to spring.The dominant species were stable,which were Charybdis japonica,Oratosquilla kempi and Collichthys lucidus.Among them,Charybdis japonica dominated during the whole year,with the average density occupying 8.07% 26.22% of the total density.The seasonal variations of stock biomass and density of nekton were in accordance with the temperature,with their highest values in summer and the lowest ones in winter.The variations of temperature and salinity showed a seasonal distribution,with high temperature and low salinity in summer and autumn,low temperature and high salinity in winter and spring.Temperature played an important role in the influence of stock biomass and density of nekton in the Lingding Bay.Comparing with the historical data,we find that main commercial fishes and shrimps have been miniaturized in the Lingding Bay of Pearl River Estuary.

In order to investigate the effect of temperature on earthworm's biomass and efficiency of vermicomposting,a simulated study of Eisenia foetida vermicomposting on organic-waste-mixed municipal sludge was carried out under different temperatures in laboratory.Results showed that under the condition with other ecological factors unchanged,there was an optimum temperature range for the growth and reproduction of E.foetida.This range was probably around 20℃,and temperatures above or below this range would do harm to earthworm's growth and reproduction.The efficiency of E.foetida vermicomposting on the organic-waste-mixed municipal sludge got the summit point when the medium temperature was 20℃,but declined under other temperatures,especially under low temperatures(5℃,10℃) where there were significant drops in the efficiency;while under higher temperatures(30℃,35℃),the efficiency drops were insignificant.In the view of industrial application,if the reproductive ability for the earthworm population and the efficiency of vermicomposting are considered together,medium temperature of around 20℃ is possibly the optimum temperature range for the vermicomposting of E.foetida on the organic-waste-mixed municipal sludge.

Based on the in situ investigations on primary production and secondary production in the Daya Bay,the potential fishery production and the maximum sustainable yield in this region were estimated.The results showed that the average primary production in the Daya Bay were 765.23 mgC·m^-2·d^-1 and 1786.33 mgC·m^-2·d^-1 in spring and summer respectively,and the average secondary production were 175.23 mgC·m^-2·d^-1 and 678.95 mgC·m^-2·d^-1 in spring and summer respectively.The potential fishery production based on the Tait's model and the Cushing's model were 3.30×10⁴ ton and 4.78×10⁴ ton respectively.Further analyzing results showed that changes of community structure in basic trophic levels may lead to overestimate the actual fishery production in the bay when basic biological productions were used to the estmiations,high community biodiversity,healthy ecosystem structure and function should be the primary basis for sustaining quantity and quality of the fishery production.

By setting fixed plots,we surveyed and analyzed all sorts of communities of Bruguiera gymnoihiza(planted for one year on leveling beach and weeds control),Kandelia candel(planted for one year on leveling beach and weeds control) and Sonneratia apetala(planted for 3 years) in the north Hezhou of Zhuhai,and investigated the species number,dominance,and regeneration of S.apetala seedlings.The results are as follows.Plant species changed a lot with the season,and the species composition is unstable.Mikania micrantha invasion directly increased the fluctuation of plant species with the season.The dominance of major communities of artificial restored B.gymnoihiza and S.apetala was reduced directly by time,and their survival rates were reduced by the invasion of M.micrantha and other Poaceae grasses.The dominance of S.apetala markedly changed with the season;the invasion of Poaceae and Asteraceae plants could not settle down,leading to a stable biotope suitable for the growth of other mangroves.

In order to explore the impact of diffusion process of Chimonobambusa utilis on other species,we selected three different vegetations(grassland,bushwood and highforest) to investigate the plant species in each vegetation,as well as average height and average coverage of species during the diffusion process of C.utilis.We found that there were 14 trees species,23 shrub species and 41 herbs species in the three sites.In the diffusion process of C.utilis,the trees species are essentially unchanged and the variation of average height is very weak.The average coverage of trees in Lanhua location decreased about 4.6% and that in Shangcigaiba location increased 12.5%.The shrub species were gradually reduced,and the average coverage was decreased.The average height showed a trend of reducing first and increasing later.The species,average height and average coverage of herbs species were significantly reduced.

To compare the purifying effect of wetland systems of Sonneratia apetala and Phragmites communis,nitrogen(N) and phosphorus(P) contents,and relevant indicators in water,soil and plant samples were determined in each season.The results show that water pollution in the two systems was serious in autumn and winter.The purifying effects of S.apetala on N and P were better than of P.communis in water,especially in winter.Soil adsorption on N and P was stronger in summer than in winter.In summer,N content in S.apetala soil was lower than that in P.communis soil,while it was opposite in winter.P adsorption in S.apetala soil was also stronger than in P.communis soil.No matter in winter or in summer,purification effect of S.apetala wetland system was better than that of P.communis system.Enrichment effect of P.communis on N was stronger than on P,while S.apetala had a relatively obvious enrichment effect on P.

The application of biological mathematical theory to the studies of ecological balance and sustainable development is a hot topic of ecosystem.In marine fisheries catch process,not only is it necessary to ensure the ecological balance,but also to maximize the biggest fishing benefits,an important issue which marine fisheries concern the most.At present,there are few researches on the catch of small discrete systems.By applying the stability theory of discrete differential equations,we attempt to discuss the species with harvesting discrete Leslic predator-prey system and obtain the sufficient conditions of the existence and partial stability of positive equilibrium point.By constructing the Lyapunov function and employing the Taylor expanding of quadratic function,we find that if the positive equilibrium exists,the system is globally and asymptotically stable.With the extreme value method,we explore the optimal harvesting strategy under the premise of maintaining the stable harvesting so as to get the optimal economic returns.Finally,the feasibility of the main results is proved by one suitable example together with its numerical simulations.The findings can provide a theoretical basis and guidance significance for actual production.

A series of assessment index systems suitable for Hainan public welfare forest ecosystem services were set up.Using shadow engineering method,alternative engineering method,et al,we assessed the economic value(year 2010) of public welfare forest ecosystem services of Hainan Province based on the data from National Forest Continues Inventory,Jianfengling Ecological Orientation Station long-term observation,and social commonality.The results show that the total value of the province's forest ecosystem services was 111.360 billion Yuan,amounting to 54% GDP of the province in year 2010,and the average forest ecosystem service was 140.9 thousand Yuan per hectare.Considering the value of negative oxide ion,the eight service functions were ordered as environmental purification> carbon fixation and oxygen release> biodiversity conservation>water conservation>forest protection>forest tourism and ecological culture>soil conservation>forest nutrition storage.

Based on the established evaluation index systems,and corresponding comprehensive assessment of urbanization development level and eco-environment quality,membership function of fuzzy sets were employed to measure the coordinative degree of urbanization and eco-environment,and to probe its tendency.The results showed that during the year 1996-2008,coordinative degree of urbanization and eco-environment exhibited apparent phases and fluctuations with upward trend on the whole.Static coordinative degree might be divided into two phases: one began from 1996 to 2004,characterized by a general coordinative development stage,with a highest level in 1998;the other one started from the year of 2005,during which static coordinative degree between urbanization and eco-environment reduced gradually till to an incongruously quality.Compared with the static coordinative degree,fluctuation of dynamic coordinative degree was smoother.It might be concluded that eco-environment responded to urbanization,while its evaluation index enhancement lagged behind the urbanization development.With accelerating urbanization,the conflict between urbanization development and eco-environment will intensify and constraints effects of eco-environment will be increased gradually,which may result in a decline of coordinative degree between them.

The ecological footprint variations of six different economic zones in Jiangsu Province from 1999 to 2008 were researched by using modified ecological footprint model,relevant statistic data of Jiangsu Province,and GIS technology;besides,the resource utility,eco-economic coordination,and socio-economic progress trend of these economic zones were further investigated in this study.The results show that currently there is ecological deficit of different levels respectively in the six economic zones.Based on the result of ecological footprint calculation,further introducing three indexes including 10000 Yuan ecological footprint,eco-economic elastic coefficient,and sustainable capability,and considering three aspects of resource utilization,eco-economic equilibrium,and overall social economic progress,we comprehensively evaluated the sustainable development of six economic zones.Results indicated that although the development was disparate among the zones,the overall sustainable development capability of Jiangsu Province kept upgraded,revealing a sound developing trend as a whole.Finally,on the basis of the current sustainable development of Jiangsu province,a proposal on coordinating more balanced development among different regions was put forward.

Based on statistical data of livestock and poultry breeding in Guangzhou City,livestock and poultry pollutant and its spatial distribution characteristics were estimated by adopting emission factor and chorisogram method.The environmental impacts of livestock and poultry pollutant on water body were also studied.The results are as follows.(1) The livestock and poultry farms of Guangzhou presented obvious circling structure and orbicular distribution around the center of Guangzhou,and the major distribution regions located in the suburb districts.(2)The total pollutant amount from livestock and poultry breeding in Guangzhou was large especially circling in suburban regions.(3)The water quality of water sources such as Liuxihe River,Dongjiang River,Zengjiang River and Pearl River West Channel etc.,was seriously affected by livestock and poultry pollutant input.According to the current situation and spatial distribution of livestock and poultry breeding of Guangzhou,pollutant prevention measures and sustainable development policies were proposed,which could be benefit to pollutant prevention and environment management of livestock and poultry breeding.Furthermore,it also provides reference for regional livestock and poultry production sustainable development research.

We analyzed the characters of temporal and spatial evolvement of sub-regional sustainable development in Qingyang since 1990.First of all,based on the theory of meta index,we proposed an indicators' system and a synthetic assessment model,which were used to assess the regional sustainable development on county level in Qingyang since 1990.After that,based on the method of gravity center shift and GIS,we analyzed the historical evolvement of spatial structure of regional sustainable development in Qingyang since 1990.The outcome showed that the integrated sustainability as a whole increased gradually from 1990 to 2008,where the driving force for increasing was due to the rapid growing of the economy and society along with the cost of abundant resources consumption and ecosystem degradation.The integrated sustainability would decrease finally under this condition.The integrated sustainability in some counties began to decrease after 2005,such as Xifeng and Qingcheng.The gravity center of sustainability of regional sustainable development moved to the south from 1990 to 2008.The gravity center of coordination and integrated sustainability of regional sustainable development undulated obviously from 1990 to 2008,indicating that the regional sustainable development was unbalance and unsteady in Qingyang.

In the 21st century,the agricultural energy-saving and emission-reduction is gaining global attention.Taking Dezhou as a case,we use different calculation models of energy carbon emissions to evaluate the status of carbon sink and carbon source from 2003 to 2008.The results are as follows.(1)The current carbon emission capacity of agriculture in Dezhou is 7.29TgCO₂eq·a^-1,including the agricultural energy consumption carbon emissions 2.81TgCO₂eq·a^-1,contribution of soil respiration 2.12 TgCO₂eq·a^-1,chemical fertilizers 0.93 TgCO₂eq·a^-1,and the emissions caused by keeping livestock 1.43TgCO₂eq·a^-1.(2) The present status of agricultural carbon sinks capacity is 9.24 TgCO₂eq·a^-1,including the carbon emissions caused by land use change 4.73 TgCO₂eq·a^-1,and the final carbon sequestration capacity through the application of organic manure and implementing straw returning 4.51TgCO₂eq·a^-1.(3) The current capacity of carbon sink is more than emissions,which suggests that it will be easy to develop low-carbon agriculture in Dezhou in the near future.From two aspects of reducing source and increasing sink capacity,we build the future low-carbon agricultural development model of Dezhou and propose some measures,such as adjusting agricultural industrial structure and improving land use,implementing conservation tillage,advocating the model of stereoscopic plantation,and developing circular agriculture with planting and breeding.

Dissolved inorganic carbon(DIC) in the waters of the Daya Bay was investigated to analyze its spatial distribution in May 2010,and to discuss the correlation between DIC and other environmental factors.The values of DIC ranged from 24.26 to 26.13mg·L^-1 at surface waters,and at the bottom layer waters the values ranged from 24.06 to 26.89 mg·L^-1.The high values of DIC at surface were found at the north area of Dalajia-Sangzhou line,and they were gradually decreased outside.At the bottom layer,the high values were in the south west region,namely,the south of Dalajia.The DIC was found to be negatively correlated with temperature and chlorophyll a,but positively correlated with pH,DO and salinity.Nevertheless,the correlation coefficients were not significant with the environmental factors.

With the acceleration of urbanization,a series of ecological problems such as population expansion,traffic congestion,environmental damage,air pollution,and energy shortage seriously restrict the sustainable development of city,and influence urban ecological security.Focused on urban ecological security problems,we took Zhengzhou as an example and adopted the matter-element analysis and entropy method to establish a model of ecological city security entropy and matter-element.First,the index data of Zhengzhou between 2001 and 2004 were processed and calculated by entropy weight method.Second,urban ecological security of Zhengzhou city in 2001 was comprehensive evaluated by matter-element analysis.The results showed that the ecological security of Zhengzhou in 2001was in unsafe condition.The evaluation results are objective and scientific,which can not only provide an efficient evaluation method for solving the urban ecological security,but also be able to understand the development of the city's status to provide a basis for working out the next development strategy.

Lakes are very important water resources and play important roles in ecology services and social economy.However,the lakes in our country become more and more eutrophic.The classical biomanipulation and non-traditional biomanipulation have become the theory foundation of lake eutrophication phytoremediation.The present paper introduces the principles,developments and applications of biomanipulation and non-traditional biomanipulation,explains the effects of carnivorous,herbivorous fish and zooplankton on controlling the amount of algae,and analyzes the applicable conditions and problems during the application of these two theories.The classical biomanipulation and non-traditional biomanipulation controlled the amount of algae by changing the structure of aquatic food web through zooplankton and fish,respectively,but can not reduce the load of nitrogen and phosphorus in water.Therefore,an effective biological manipulation must be combined with other methods.

Macroecology is a newly developed subject in recent years.We summarized the characters,research status,main problems and hotspots of macroecology in this paper.Hotspots of macroecology were focused on the model of species distribution and abundance,figure and distribution range,biodiversity latitude pattern,biological protection,theory of metabolism,and so on.Though problems such as study methods,quality of data,means of statistic,dubious research scale still exist,it possess important meanings in the necessitous regional environment problems and protection of biodiversity.And with the development of study methods and means,macroecology will play more important roles in the future.