The barycenter calculated by composite proportion is parameterized according to the data of statistical yearbooks to calculate and interpret the geometry barycenter of land and entirely territory,as well as the barycenter of population,economy,ecology,water resource,and commissariat.By comparing the distance between the barycenters and Beijing,we find that the deviation is about 620 to 1487 km,which is not good for region administration.Besides,we analyze Beijing's problem within the confines of the factors such as water,gas,landform,geology and earthquake after establishing capital in Beijing 61 years later.We discuss the area of the fullest water, the martial security area under threat of nuclear warfare,the area of the most products,and the area of the best anthropogeography in the best location for establishing a new capital.Finally,we evaluate the loss and benefit,physical cost and opportunity cost,development of Beijing after its moving to a new place,and choice of moving or not using different evaluation methods.

We carried out a small scale control experiment by using the Italian ryegrass(Lolium multiflorum L.) planted in winter paddy-field as research material,and combining conventional ensiling methods.We designed the treatments of separating water(eliminating the leachate produced in ensiling process) or non-separating water,and adding different kinds of additives in the process of ensiling.After ensiling,we evaluated the quality and nutritive value of ensiled Italian ryegrass,investigated the effects of different treatments on the ensiling of Italian ryegrass,and discussed the reasonable methods and optimum conditions for ensiling Italian ryegrass under conditions of high temperature and humidity climate in southern China.The results of sense organ,pH value and nutritional ingredient showed that the treatment of separating water and adding lactic acid,to some extend,was preferable,as compared to other treatments,therefore it can make stable and high quality silage.

The distribution of cultivable organic phosphate solubilizing bacteria(OPB) and inorganic phosphate solubilizing bacteria(IPB) in the sediment of Dishui Lake and its diversion rivers was studied in 2010.Results showed that the annual average values of OPB and IPB in sediment of diversion rivers in front of the inlet gate were(2.76×10⁴±1.31×10⁴) and(7.19×l0³±3.98×10³) CFU·g^-1, respectively;while in rivers after the gate they were(1.05×10⁴±3.56×10³) and(2.54×l0³±8.77×10²) CFU·g^-1,respectively.The annual values of OPB and IPB in sediment of Dishui Lake were(6.69×10³±2.63×10³) and(1.66×10³±5.83×10²) CFU·g^-1, respectively.In both Dishui Lake and its diversion rivers,close correlations were observed between OPB(or IPB) amount in sediment and phosphorus concentration in water.OPB or IPB amount had a significantly positive relationship with total phosphorus(TP),and the related coefficients were higher than those with bacteria,total dissolved phosphorus(TDP),and reactive phosphorus(AP).

The change of soil carbon pool has a significant impact on the global greenhouse effect and carbon cycle.Urban soil is an important part of the global carbon cycle.The impact of urbanization on soil organic carbon pool needs to be examined.Based on the field investigation and samples in Shenzhen City,soil organic carbon content,density and distribution were analyzed.The soil depth of samples from different land use types were 0～10,11～20 and 21～30 cm.The results are as follows.(1) The average soil organic carbon content was 0.72～40.52 g·kg^-1,and average soil organic carbon density was 0.27～13.36 kg·m^-2 in the soil depth of 0～30 cm.(2) The soil organic carbon content and density decreased with the increase of soil depth.In the soil depth of 0～10 cm,the average soil organic carbon content ranged between 1.56 to 71.88 g·kg^-1,and the average organic carbon density ranged between 0.18 to 7.05 kg·m^-2.In the soil depth of 11～20 cm,the average soil organic carbon content ranged between 0.59 to 36.79 g·kg^-1,and the average organic carbon density ranged between 0.09 to 4.5 kg·m^-2.In the soil depth of 21～30 cm,the average soil organic carbon content ranged between 0 to 12.90 g·kg^-1,and the average organic carbon density ranged between 0 to 1.78 kg·m^-2.(3) The soil organic carbon content and density in forest land decreased with increasing altitude,and those in urban construction land and unused land were very low.(4) The land use change could affect the storage and distribution of soil organic carbon.

The macrobenthic community structures were studied in two mangroves,natural Kandelia candel and Sonneratia apetala plantation,in Qiao Island of Zhuhai.The results showed that the macrobenthic number and composition in natural Kandelia candel were very different from those in Sonneratia apetala plantation.The average macrobenthic biomass and diversity in Kandelia candel were 668.64 g·m^-2 and 8370·m^-2,while they were 511.64 g·m^-2 and 4748·m^-2 in Sonneratia apetala.There were some differences in macrobenthic community structure in different tidal zones in mangrove sections.The highest biomass and density of Kandelia candel were observed in the mid-tidal region,which were mainly influenced by the Arthropods and Mollusks.The highest density of Sonneratia apetala was also found in the mid-tidal region,but the biomass changed irregularly.The characteristics of macrobenthic community in two sections of mangroves showed obviously seasonal changes.The highest biomass was in autumn;the highest density was in winter, and the lowest in summer;the lowest diversity was in summer;the highest diversity in Kandelia candel was in spring;the highest diversity in Sonneratia apetala was in autumn.The results indicated that the factors including quality of soil environment,the height of plants and shelter,as well as the air and light conditions in forest ecosystem caused the differences in macrobenthic community.

Phytoplankton communities at the water depth of 0.5,5,and 10 m were investigated in the lacustrine zone of Dashahe Reservoir in the winter from December,2009 to February,2010.Total precipitation in the three months was 263 mm;temperature ranged from 15.5℃to 19.4℃;the water column was fully mixed.Sixty four species of phytoplankton belonging to six phyla were identified. Total phytoplankton abundance ranged from 4.1×10⁶ to 14.8×10⁶ cells·L^-1.There was no significant difference in the dominant phytoplankton species at the three water layers.Anabaena circinalis and Microcystis aeruginosa were the predominant species,and contributed to about 70%of total abundance in all of the sampling periods at all depths.Anabaena and Microcystis blooms slightly occurred in the December of 2009 and February of 2010.The regulating buoyancy of cyanobacteria,as well as low availability of phosphorus and light led to the dominance of the two species.

Biological invasions are seriously challenging the local ecosystems and economy worldwide.Thus it is very important and urgent to quantitatively assess the risk of invasiveness for the alien species.According to the geography and climate characteristics of Suzhou City and the preexisting weed risk assessment models,as well as the updated research results,a risk assessment model for Suzhou City was set up,which adopted a set of indices commonly used by other models plus two new ones:self compatibility and DNA C-value.The invasive risks of Galinsoga parviflora were assessed by using the model.According to this risk assessing model with a full mark of 100,Galinsoga parviflora gets a mark of 68,which suggests it is in a medium risk level.It should be controlled before its outbreak in Suzhou.

To improve the purification capacity of sulphur by vegetation in the acid polluted areas,we study the characteristics of sulphur accumulation in 41 plant species in the Xiqiao Mountain that is located at ceramic industry areas in Foshan.The results showed that the sulphur content in leaves or aboveground part of 41 plant species was in the range of 1.81-16.47 mg·g^-1,with the mean of 4.00 mg·g^-1,which was higher than the average sulphur level of plants in other regions of China.Leaf sulphur contents of Pinus massoniana and Schima superba were 2-3 times as those in the relatively clean site,Dinghu Mountain.Among the sampled species,leaves of Symplocos chinensim,Aporosa dioica,Symplocos lancifolia and Lindera glauca had the highest sulfur contents,which were 16.47,12.42,11.31 and 6.68 mg·g^-1,respectively. We also observed that the plant species within the same family of Symplocos showed a consistently excellent capacity of sulphur accumulation, suggesting there might consist of some other species in this family having good potentials in sulphur accumulation,which needs further studies.

In this paper,we analyzed and ordered the 51 plant species in 40 sampling locations in trail wetlands in Yanqing County, Beijing City by using TWISPAN analysis,and divided the vegetation communities into seven types,which were type Artemisia capillaris-Setaria viridis-Artemisia annua,type Artemisia lavandulaefolia-Artemisia capillaris-Lespedeza caraganae-Setaria viridis, type Artemisia lavandulaefolia-Artemisia capillaris-Setaria viridis-Glycine soja-Sonchus arvensis,type Setaria viridis-Xanthium sibiricum-Melilotus officinalis-Chloris virgate,type Bidens tripartita-Artemisia lavandulaefolia-Inula japonica-Artemisia sieversiana-Phragmites australis,type Typha orientalis-Phragmites australis-Zizania latifolia-Glycine soja-Bidens bipinnata,and type Juncus effusus-Cyperus fuscus-Echinochloa crusgalli.We also sorted and analyzed the 51 plant species by double variables principal coordinates analysis(DPCoA).The results showed that there were two succession rules for plant communities in this area,which were the succession from typical stand wetland plant species to ordinary wetland plant species,and the succession from hygrophilous plants to terraneous plants.The vegetation restoration in sand-mining wetland should not only restore soil nutrient,but also regulate water condition.The findings can provide a scientific support for mining trail wetlands restoration.

Researches were made on the species composition characteristics of spring ephemerals in the Baishilazi Reserve;besides,the species diversity of spring ephemerals in different forest types were quantitatively studied by using species richness index, Shannon-Wiener diversity index,Pielou evenness index,and Simpson dominance index.The results showed that there were 12 species and;
2. forms of spring ephemerals,belonging to 11 genera and 7 families.Anemone amurensis was the dominant species of the spring ephemerals synusia.The species number of the spring ephemerals in Fraxinus rhynchophylla forest was the highest,followed by Betula costata forest,Korean pine broad-leaved forest,Larix forest;the species numbers of the spring ephemerals in Quercus mongolicus forest, mixed forest,Picea jezoensis and Abies nephrolepis forest were the least.The variation trend of the diversity index generally was ordered as coniferous and broad-leaved mixed forest>deciduous broad-leaved forest>coniferous forest.The variation trend of the evenness index was similar to the diversity index,but opposite to that of dominance index.The species diversity of the spring ephemerals in Korean pine broad-leaved forest was the highest;the species distribution was even;the synusia structure was fairly stable.

Based on the different vegetation area occupied by the construction of Zhengzhou-Xi'an passenger dedicated railway,the authors quantitatively analyzed the vegetation biomass losses of cropland,forest land,and wasted land.The results showed that the vegetation area occupied by the construction was 1526.12 hm²,of which cropland,forest land and wasted land accounted for 1240.17, 232.99 and 52.96 hm²,respectively.During the four year construction period,the total vegetation biomass loss would be 65081.82 t,of which 30535.64 t was cropland vegetation loss(46.9%),33077.59 t was forest land vegetation loss(50.8%),and 1468.59 t was cropland vegetation loss(2.3%).1220.90 t vegetation biomass would be compensated in the early stage after the vegetation restoration measures such as slope vegetation protection,stations afforestation took effect.

The community structure of Rotifera and ecological assessment of water quality were studied by investigating the species composition,density seasonal dynamics,biodiversity and Q_B/T index in the sampling stationsⅠ-Ⅵof Jinshuitan Reservoir,Zhejiang. During one year study,45 species of Rotifera were found,and 37 species were pollution indicator species,of which oligo-Pmesosaprobic,β mesosaprobic andβ-amesosaprobic species accounting for 32.4%,35.1% and 24.3% of the total indicator species respectively.The dominant species were Keratella cochlearis,Polyarthra trigla and Trichocerea similis.Community density of Rotifera ranged from 4.8 to 542.5 ind·L^-1,with an average of 135.7 ind·r^-1;Shannon-Wiener index(H^T) ranged from 2.60 to 3.65,with an average of 3.20;QB/T value ranged from 0.83 to 2.50,with an average of 1.39.Rotifera density and H' value were lower,but Q_B/T value was higher in the stationsⅠ-Ⅱ than in the stations Ⅲ-Ⅵ.Q_B/T value decreased with the increasing of water transparency.Jinshuitan Reservoir was in oligo-mesosaprobic status,of which stationsⅠ-Ⅱ were mesosaprobic,while stations Ⅲ-Ⅵ were oligo-βmesosaprobic.

The biosorption of simulation wastewater with coexisted Cr(Ⅵ),Ni(Ⅱ) and Cu(Ⅱ),and three kinds of actual wastewaters by Candida lipolytica was investigated.The results showed that initial pH,contact time and biosorbent dosage were the major influencing factors.Research on the dynamics reflected that the biosorption complied with both the first-order and the second-order kinetic models,and the second-order kinetic models had higher correlation coefficients,confirming that the biosorption process included multiple steps and chemical adsorption was the rate-determining step.After the wastewater containing 18.7-37.86 mg·L^-1 of Cr,2.39-9.21 mg·L^-1 of Cu,2.27-9.87 mg·L^-1 of Ni and 0.43-1.32 mg·L^-1 of Zn was absorbed with 1 g·L^-1 biosorbent for 120 min,the biosorption rates on the above metals were 81.6%-84.6%,84.0%-100%,84.1%-100% and 93.9%-100%,respectively.The results suggested that C.lipolytica was an effective strain to remove combined pollutants from aqueous solution.Moreover,proteins,lipids and carbohydrates of the biosorbent participated in the binding of these heavy metals.The main functional groups were -OH,-NH₂,-CH₂,-CH₃,-COOH,-CHO,C=C,-PO₄^3- and -SO₃H.

The community structure and temporal-spatial variations of crustacean zooplankton in the lower reaches of Ganjiang River were investigated in June and November 2009 and April 2010.A total of 21 species were recorded,among which 14 species were cladocerans and 7 species were copepoda.B.fatalis,M.micrura and Mesocyclops sp.were dominant species during the study.Mean maximal density and biomass(11.1 ind.·L^-1 and 0.127mg·L^-1) of crustacean zooplankton in main stream of the lower reaches of Ganjiang River occurred in June while the mimimun(1.59 ind.·L^-1 and 0.01mg·L^-1) appeared in April.The densities of cladocerans and copepoda in the Yuanhe tributary of Ganjiang River in June(4.97±13.28 ind.·L^-1 and 2.07±4.85 ind.·L^-1) and November(2.07±5.21 ind.·L^-1 and 2.24±5.22 ind.·L^-1) were higher than in the main stream and Jingjiang tributary of Ganjiang River.Shannon-Wiener index(H') and Margalef index(d) showed that water quality in the lower reaches and its tributaries of Ganjiang River was moderate contamination or serious contamination.Water temperature and edible phytoplankton biomass were important factors affecting temporal and spatial variations of crustacean zooplankton.

The acid hydrolysis and manual counting methods were used to estimate the cell numbers in colonies of Microcystis aeruginosa,M.botrys,M.wesenbergii,M.firma,M.viridis,M,novacekii,M.flos-aquae,M.ichthyoblabe from Lake Chaohu.Through statistical analysis,the regression equation model of the maximum projected area of the colonial Microcystis and its cell numbers was established.These models can be used to estimate the cell numbers in the colonial Microcystis.

Negatively environmental impacts of traditional chloride-based deicing salt have become increasingly obvious.The environmentally friendly alternative materials with advantages of low cost,valid snow melting,weak environmental impact are urgently to be developed.This paper reviews the current status of applications,mechanism of environmental impacts on soil-water-plant,and metal corrosion on transport infrastructure of the chloride-based deicing salt.The research progress and applications of non-chloride and mixed alternative snowmelt agent materials are described in detail.Development of environmentally friendly deicing salt and effective countermeasures on alleviating deicing salt environmental influences are presented,in the hope of settling the problems in developing and applying deicing salt alternatives.

The nitrobenzeneis faint yellow,with bitter almond taste poisonous substance,which is hardly biodegraded.It is widely used in chemical industry,dye,pharmacy and so on.Nitrobenzene and its substituted compounds are a group of priority pollutants characterized by chemical stability,high toxicity,and biological accumulation.The emission of nitrobenzene brings serious threat to the environment.Therefore,the treatment of this toxic organic pollutants has been the focus of research.The common technology in removal nitrobenzene includes physical methods,chemistry methods and biological methods.The biological methods can degrade pollutants greatly with low cost.To treat the waste water and its substituted compounds and to remedy the environment polluted by these compounds,microbial degradation had advantages over other methods.Over the recent years many excellent nitrobenzene degradation bacteriumhave been obtained.This paper summarized the research advances in the microbial degradation of nitrobenzene by terms of the types of degrading microbial、degradation pathways、co-metabolism、immobilization、genetic engineerings、degradation of high-salt conditions.