The decompositions of two dominant plant species litters under different grazing intensity in alpine meadow on the Northwester Sichuan were studied. The relative weight loss in the litter of Roegneria nutans is 26.0, 27.2, 29.6 and 32.8% for no grazing, light grazing, moderate grazing and heavy grazing, respectively; while 44.0, 46.2, 50.4 and 56.2% for the litter of Kobresia setchwanensis. Relative carbon loss in the litter of Roegneria nutans was 26.1%, 27.5%, 29.4% and 32.9% for no grazing, light grazing, moderate grazing and heavy grazing, respectively; while 41.9%, 44.3%, 48.5% and 54.4% for the litter of Kobresia setchwanensis; Relative nitrogen loss in the litter of Roegneria nutans was 13.6%, 14.4%, 17.3% and 19.1% for no grazing, light grazing, moderate grazing and heavy grazing, respectively; while 39.4%, 41.4%, 46.4% and 52.8% for the litter of Kobresia setchwanensis. It is concluded that increased grazing intensity tended to increase the decompositions of litters and accelerate the carbon and nitrogen cycling rates within the plant-soil system in the alpine meadow.
Based on routine monitoring data in Xiangxi river and its tributaries of Gufu river, Gaolan river and Jiuchong river from August 1999 to December 2006, physico-chemical factors were analyzed, and spatio-temporal distributions of such factors were compared in this paper. The results show that waters of Xiangxi watershed are neutral and partial alkalescent, belong to moderate hardness, concentration of dissolved oxygen is high, contents of chemical oxygen demand and chloride are low, so these waters have well buffer capacities. There are significant seasonal variations in most physico-chemical factors in these four rivers, but annual variations are not significant. There are high contents of nitrogen in this watershed, and Gufu river has the highest contents of total nitrogen which influenced by the domestic sewages and agricultural activities. Water quality is relative poor in Gaolan river, and phosphorus pollution is serious in Xiangxi river; the best water quality presents to Jiuchong river which has high forest coverage. High nitrogen contents in these four rivers are caused by non-point source pollutants, while point source pollutants of phosphorus play an important role in Xiangxi river. Soil erosion represents the major non-point source, while the drainages of phosphorus diggings and factory discharges play the most important role in the point source of phosphorus. This research suggests that measures must be taken to control the point source pollutants of phosphorus in Xiangxi river in order to protect Xiangxi Bay of the Three-Gorge Reservoir.
Based on a land use map created from a satellite image from 2005,a map of agreenbelt system from 2005 and a map of a planned greenbelt system, a number of ecological networks of Chongming Island were designed using network analysis methods. Using network indices such as α,β,γ indices, cast ratio and corridor metrics, an optimal ecological network was selected among those ecological networks. The optimal ecological network was then overlaid on the existing plans for a greenbelt system on a GIS platform. Then we used landscape spatial pattern analysis and a series of landscape pattern metrics on Fragstats to assess the present situation, the planned greenbelt system and the optimal ecological network for Chongming Island. Our results showed that the greenbelt system plan for Chongming Island was an improvement which indicated by decrease in patch density and increase in edge density, mean patch fractal dimension on the patch level, landscape diversity, landscape evenness, and landscape connectivity. Compared to the existing greenbelt system plan, the optimal ecological network brought a further improvement to the greenbelt system both on quality and quantity of Chongming Island.
The pigment composition, the absorption and fluorescence spectra of Haematococcus in different growth phases was measured in this study. The result showed that the wavelength is excitated at 490nm, two fluorescence emission at 710nm and 730nm in the stage of green cells were observed, while in the stage of red cells, a fluorescence emission only at 730nm was observed. The results suggested there are significant differences in PSI structure, constitute and distribution of chromoprotein in different stage of Haematococcus.
This paper evaluates the ecological landscape of the Riparian buffer of the Dongfenggang of Suzhou River by the method of AHP, and aims to build a complete and suitable index system for the evaluation of the city riparian buffers. The results show that the riparian buffer of the Dongfenggang of Suzhou River achieves overall Ⅱ level and I level on the index of design of plant community, the richness of plant species, the control of pests, and the use of pesticide and chemical fertilizer while Ⅲ level on the index of landscape coordination and continuousness and the cost of management. This paper also discusses the extension of this evaluation system.
Effects of two types of inorganic carbon sources on the growth of Pinguiococcus pyrenoidosus CCMP 2078 were investigated in this study. The results showed that the growth of P.pyrenoidosus CCMP 2078 was significantly promoted by adding appropriate amount of NaHCO3 or CO2, and there were significant differences among different additions of NaHCO3. The optimal concentrations of NaHCO3 added for one time and added equally for several times were 5 mmoL·L-1 and 20 mmoL·L-1, respectively. For the latter treatment, parameters of cell density, dry weight, and the specific growth rate reached to the highest value, which were 8.93×106cells·mL-1, 0.247 g·L-1, and 0.225 d-1, respectively. When CO2 content was 0.5%, P. pyrenoidosus CCMP 2078 reached to the highest growth rate, and parameters of cell density, dry weight, and the specific growth rate were 3.83×107cells·mL-1, 0.42 g·L-1, and 0.212 d-1, respectively.
Effect of temperature and body size on oxygen consumption rate and ammonia excretion rate of Monodonta labio were determined using hydrostatic method. The results showed that there were negative relationship between dry weight of soft tissue (W) and oxygen consumption rate (RO) or ammonia excretion rate (RN) of Monodonta labio at 16-33℃. The relationships between dry weight and RO and between dry weigh and RN could be expressed by a power function as: RO=aW-b and RN=a1W-b1. The oxygen consumption rate and ammonia excretion rate of Monodonta labio increased with increasing water temperature and reached the maximum at 29℃. The relationships between water temperature and RO and between dry weigh and RN could be expressed by an exponential function as: RO=cedT and RN=c1ed1T. The highest RO/RN (atomicity O/N) was observed at the temperature between 16-20℃. The Q10 value ranged from 0.56 to 3.74. ANOVA showed that the RO and RN were significantly affected by water temperature and dry weight of soft tissue (P<0.01).
It is important to protect the structure, functions and process of nature ecosystem. This paper discussed the services valuation of forest ecosystem in nature reserves, which taking the Gudou Mountain Nature Reserve of Guangdong as an example. The methods applied in this paper included market-method, shadow-engineering method, product-cost method and substitute-expense method. Results showed that the total ecological value of this reserve was 57.887 615million Yuan. Among that, the production value was about 6.9 377 million Yuan; the production from the standing trees was about 4.05 million Yuan which was increased by tourism; the production from improving atmospheric environment was about 32.2 177 million Yuan; the production value from water holding and water cleaning was about 5.809 million Yuan and the value from soil conservation was about 8.878 215 million Yuan. The object of this study was to show the huge valuation of ecosystem services that provided by forest ecosystem of nature reserves and bring more attention from society to the valuation of ecosystem services, strengthen management and protection the forest ecosystem services.
Including 6 new record genenra and 1 new record family, there are 10 species of seed plants belong to 9 genera,8 family in Jinfo Mountain Nature Reserve reported firstly. They are Machilus litseifolia(Lauraceae),Distylium buxifolium(Hamamelidaceae), Parrotia subaequalis(Hamamelidaceae), Ammannia baccifera(Lythraceae), A. multiflora(Lythraceae), Syzygium buxifolium(Myrtaceae), Chimaphila japonica(Pyrolaceae), Pinguicula alpina(Lentibulariaceae), Blainvillea acmella(Compositae), Cypripedium fargesii(Orchidaceae).
Based on the frequency of acid rain, pH and the contents of NO3- and SO42- in the acid rain of Guangzhou city in recent years, the change of the acid rain type and its ecological implication were studied. The conclusion shows that in the past a few years, the frequency of the acid rain tended to increase, especially after 2001, the trend is becoming more apparently. The acid rain intensity was weak, and the type of acid rain was still belonged to sulphuric acid rain type. But as the contribution to acid rain of SO2 was reducing and the concentration of NOX was increasing rapidly, the type of the acid rain was approaching to nitric acid rain type. Although the type of acid rain is not nitric acid type now, yet this transformation has its profound ecological meaning, especially the influence of nitrogen in the rainfall.
The wetland landscape pattern research has been one of the key research fields of landscape ecology and Global Changes. 3S technology and modeling methods have been applied widely and proved to be important approaches in wetland landscape researches, Based on researches of 3S and model methods in wetland landscape pattern, this paper reviews the following research methods such as the RS imagery data selection and classification, the measurement of wetlands' basic data and parameters, the landscape index and dynamic models' application in quantitative analysis of wetland landscape patterns and changes. Several key problems including the increase of classification and cartography precision, application and improvement of dynamic models are also emphasized in this paper.
Invasive plant is one of the most important ecological problems at global level. Invasive plant has significant impacts on the ecosystem biomass, productivity and carbon fixation. We reviewed and analyzed the impacts of invasive plant on such ecological parameters. while most studies showed that exotic plant invasion would increase ecosystem biomass and productivy, some studies indicated adverse conclusions. The reasons causing the increase and decrease of bioamass and productivity were complicated. In the future, systematic and comprehensive studies on invasive plant are necessary, and the spatial heterogeneity and temporal scale would be paid more attention to this research.
In order to facilitate reasonable exploitation and ecological protection of coastal wetlands in Jiangsu province, on the basis of summarizing existing researches, making field survey, and data analyses, this paper applied the techniques of remote sensing and GIS on the changes of land use in coastal wetlandsand the ecological effects for different land use patterns. The land use pattern of coastal wetlands is divided into three types: feasible pattern, degenerative pattern and premature pattern. Furthermore, in this paper, researcher explored the ecological and environmental problems of each land use pattern, and finally, proposed the approaches for ecological protection of coastal wetlands' usage.
Researches have shown there is a close relationship between soil fauna and soil environment, the structure, the function,and the positive irreplaceable function in the course of the soil ecosystem, it plays the critical role in natural processes of soil ecosystem, Soil fauna community becomes one of the focuses in ecology and soil studies. In this paper, the research progress of fauna composition was introduced in China, and the latest researches of soil fauna community in forest and agriculture ecosystem are presented from structure, function and succession at home and abroad, including the assessment of soul environment, the decomposition of organic matter, the indication of soil health, the relation with soil contaminated and soil nutrition. At last, the prospect aspects for future study were analyzed from the change of global environment, the course of soil ecosystem, and the diversity of soil biology.
The developed regions which has been already urbanized are now facing various resource and environment problems. The proportion of agriculture in GDP and the reserved space was reducing constantly. In addition, the development was restrained because of the pollution and its negative impacts. Many studies revealed that the agriculture with the important ecological service function was indispensable for the urban sustainable development. The tactics for sustainable agriculture is proposed in two aspects, one is to maintain a healthy agro-ecosystem, another is to adopt suitable and ecological technologies for agricultural environment and, resource management.
Phytoncidere is a type of volatile organic compound with fragrant odor emitted from plant tissues naturally. As one of health-related ecotourism resources, Phytoncidere has many sanitarian functions, such as bacteriostasis, preventing and curing diseases etc. The discovery, biosynthesis approach, influences of environmental factors on releasing of Phytoncidere and their effects on human health are reviewed in this paper. The research techniques and applications of Phytoncidere are also discussed. Based on the present studies on Phytoncidere, most researches in this area has been focused on the composition, content, medical mechanism and releasing mechanisms of Phytoncidere. However, further studies on the taboo of Phytoncidere, the best content and time for human body, the best combination of plant species and most effective approach to utilize the Phytoncidere are needed in the future.
