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To screen copper tolerant species, Four ecotype plants, Catalpabungei C. A. Mey, Catalpa ovata G. Don, tall fescue (Festuca arundinacea), and Sedum lineare Thunb, were planted in soil contaminated by Cu in greenhouse to reveal their characteristics of survival, growth and morphology, as well as copper uptake, accumulation and translocation in plants. The survival rate(S) of Catalpabungei C. A. Mey under Cu stress was high, while that of Catalpa ovata G. Don was just the opposite. With the increasing of Cu concentrations in soil, tree height(H) increment percents of both Catalpabungei C. A. Mey and Catalpa ovata G. Don declined significantly(significant level, α=0.05), but for stem bases(D) there were not obvious differences. The translocation factors (TF) and bioconcentration factors(BCF) of Catalpabungei C. A. Mey and Catalpa ovata G. Don were both lower than 0.5. The Cu content in roots of Catalpabungei C. A. Mey was significantly positively correlated with that in soil(r=0.98; P

The Yellow River Delta region in China is a land area of 1,200,000 ha with rich natural resources. Adverse environmental conditions, such as low rainfall and high salinity, promote the dominance of black locust trees for afforestation. With the increase of CO2 in the atmosphere, this forest and others throughout the world have become valued for their ability to sequester and store carbon. Forests store carbon in aboveground biomass (i.e. trees), belowground biomass (i.e. roots), soils and standing litter crop (i.e. forest floor and coarse woody debris). There are well-developed methods to sample forest ecosystems, including tree inventories that are used to quantify carbon in aboveground tree biomass. Such inventories are used to estimate the types of roundwood products removed from the forest during harvesting. Based on standard plot inventories and stem analyses, carbon sequestration estimates of trees were 222.41 t ha−1 for the Yellow River Delta region accounted for 67.12% of the whole forest. Similar...

Currently, China is home to more than four million hectares of oil plants nationwide, and 154 kinds of energy trees could produce seeds containing more than 40 percent of oil, with total production of the seeds totaling five million tons. Another 57 million hectares of waste land are available and suitable for planting trees for the production of forest-based bioenergy, of which there is 630,000 hm2 beach land in the middle and lower reaches of Yangtze River where is suited for poplar growing. In order to approach the potential of poplar biomass production, the test was conducted in the paper. The result indicated that in the poplar forest ecosystem the herbaceous biomass production was 15.554 t/hm2. While biomass production for trees was 43.164 t/hm2, totally in the poplar plantation ecosystem biomass production reached 58.718 t/hm2. As well, poplars growing added incomes for local farmers.

Taihu Lake is located at the center of Changjiang delta region, the Lake and its effluent rivers are important water sources for 40 million around inhabitants and rapidly increasing industrial factories in Shanghai, Ji-angsu and Zhejiang. The pollutants originate mainly from acidy rain, home sewage of the vast number of inhabitants, livestock manure, agricultural fertilizers & pesticides applied over fields in the drainage basin, and the industrial sewage. Due to the kinds of pollutants, the Lake water is getting highly eutrophic, with frequent blooms of blue-green algae. Compared with point-source pollutants, diffuse pollution is much com-plicated and difficult to control. Thus combating non-point pollution (NPP) is paid much great attention. Based on analysis on source-sink of NPP in Taihu Lake basin, it is concluded that the function of forests on NPP control is multiple and important by both source reduction and sink expansion. The primary objective of planting trees through constructing forested wetlands and establishing riparian forest buffers is to control soil & water erosion, decrease agrochemicals application, and improve farming conditions in the region of Taihu Lake basin. Moreover forests help to intercept acidy rain, protect streambanks, uptake nutrients, hold up pollutants and provide habitat for wildlife.

To reveal the biological characteristics of urban forest soil and the effects of soil enzyme on soil fertility as well as the correlation between physicochemical properties and enzyme activities, 44 urban forest soil profiles in Nanjing were investigated. Basic soil physicochemical properties and enzyme activities were analyzed in the laboratory. Hydrogen peroxidase, dehydrogenase, alkaline phosphatase, and cellulase were determined by potassium permanganate titration, TTC (C19H15N4·Cl) colorimetry, phenyl phosphate dinatrium colorimetry, and anthrone colorimetry, respectively. The result showed that soil pH, organic carbon (C), and total nitrogen (N) had great effects on hydrogen peroxidase, dehydrogenase, and alkaline phosphatase activities in 0–20 cm thick soil. However, pH only had great effect on hydrogen peroxidase, dehydrogenase, and alkaline phosphatase activities in 20–40 cm thick soil. Hydrogen peroxidase, dehydrogenase, and alkaline phosphatase were important biological indicators for the fertility of urban forest soil. Both in 0–20 cmand 20–40 cmsoil, soil enzyme system (hydrogen peroxidase, dehydrogenase, alkaline phosphatase, and cellulase) had a close relationship with a combination of physicochemical indicators (pH, organic C, total N, available K, available P, cation exchange capacity (CEC), and microbial biomass carbon (Cmic)). The more soil enzyme activities there were, the higher the fertility of urban forest soil.

Organic acid exudation from the roots of Chinese fir (Cunninghamia lanceolata) and Masson pine (Pinus massoniana) seedlings under low phosphorus stress was studied using the solution culture method. The results revealed that organic acid exudation from the roots of Chinese fir and Masson pine seedlings under low phosphorus stress increased. Compared with P3 (KH2PO4, 0.5 mmol/L), the average organic acid exudation from the root of Masson pine seedlings under P0 (KH2PO4, 0 mmol/L), P1 (KH2PO4, 0.03 mmol/L) and P2 (KH2PO4, 0.09 mmol/L) increased by 328.6%, 267.9% and 126.4% respectively. Masson pine from Zhejiang Province in China had the highest organic acid exudation. Under low phosphorus stress, the increase in organic acid exudation from the different provinces of Chinese fir and Masson pine varied. Masson pine from Zhejiang Province mainly increased oxalic acid, tartaric acid, citric acid and malic acid exudation, that from Guangxi Province mainly increased oxalic acid and tartaric acid exudation, and that from Guizhou Province, China mainly increased oxalic acid, tartaric acid and malic acid exudation. Chinese fir mainly increased oxalic acid and tartaric acid exudation.

The copper mine tailing dam in Tongling city has highly potential environment risk. To recognize the underground distribution of Cu in the mine tailing dam, nine profiles were excavated and surveyed in the central area of the deserted copper tailing dam. Soil samples from different layers of each profile were collected separately. The copper content in the tailing dam exceeded the toxic threshold of plants much, indicating high potential risk to local environment. The Copper of total and available contents both had the high heterogeneity in the horizontal direction. In the vertical direction, the total and available form of Cu displayed an opposite trend. The copper in the surface soil was easier to resolve, transport and transform than that in the subsoil.

At present China faces various environmental problems such as air pollution, noise, soil erosion, etc., of which water pollution is the vital issue. In order to cope with the problem, it is significant to develop urban forest shelter belts, because forests have highly modified soils that promote infiltration of water, thereby reducing surface runoff, preventing NPS pollution. Organic matter, roots and soil fauna maintain the porosity and permeability of the forest floor, and evapotranspiration keeps soil unsaturated. While the replacement of forested areas with impervious surfaces increases runoff, prevents infiltration, and leads to elevated levels of phosphorus loading and eutrophication of waterways. Thus by building forest shelter belts they can protect waterways and produce clean water by controlling surface runoff, flooding and erosion, and promoting infiltration of water into forest soils.

Recently affected both by high oil prices continue to run and environmental pollution and global climate change, the world set off a new round of biomass energy development and utilization. In China the situation that shortage of power seems getting much more serious. But it is well known that less arable land is one of China's basic national conditions. In this context shoreline and other marginal lands to cultivate energy crops for biomass energy play an important role in the field. However in the past two decades the East China Sea environment has faced huge stresses from anthropogenic activities and population growth in the Yangtze River drainage basin and the coastal areas. In order to cope with these environmental problems and provide alternative energy, planting trees is of importance and significance for improving environment and producing renewable biomass energy in the region. Moreover biomass plantations are an effective way to reduce greenhouse gas emissions and provide rural people with a diversified source of income and products with multiple uses.

Water pollution in Taihu Lake has become one of the most serious environmental problems that draws public attention and needs to be solved as soon as possible. It was well known that forest could play an important role to control soil & water erosion, uptake extra soil nutrients as well. However forest coverage is rather low and woodlands are extensively managed in the headwaters region. Thus the fertilizer loss resulted from the erosion of soil and water in sloping field has acted as an important role in the course. In view of the situation, enhancing forest establishment and management is significant. The primary objective of applying hedgerows is to control soil & water erosion, and improve farming conditions on slope field in headwater region of Taihu Lake basin. While building riparian forest buffer zone is helpful to protect riverbank, uptake nutrients, hold up pollutants and provide habitat for wildlife. The planting techniques of hedgerows in slop fields and riparian forest buffer zone along channels were discussed in the paper, which is considered as a vital measure to control agricultural non-point source pollution.

At present the environment in Yellow River delta region is particularly badly eroded. In view of the situation, use of vegetation for environmental protection is most effective. In order to select suitable tree species, some physiological parameters such as proline content, ratio of bound water and free water, relative conductivity of leaves were applied to this experiment to probe the capability of trees to resist salinity stress. Based on the testing results, these tree species such as R. hispida, F. velutina, C. korshinskii, N. sibirica, T. chinensis, R. typhina, S. matsudana, A. fruticosa and A. altissima were chosen and planted in the area. The result of stand inventory implemented in the year showed that these trees grew well, especially for L. chinense, the biggest height increment reached 1.73 m, and the mean was 1.45 m; and the biggest basal diameter was 1.52 cm, the mean was 1.21 cm. Hence it was concluded that planting trees could prevent soils from salinization and protect lands from degradation.

With world population growth, the demand for food, vegetable and so on is increasing. However, arable land area cannot expand. Moreover it would decrease owing to land use change with socio-economic development. Especially in China that is the most populated country in the world, while its cultivated land area could not match with the population, farmland is gradually declining with urbanization progress. In order to meet the demand to grain production and alleviate the pressure on current arable land, wasteland must be reclaimed. Forestation is not only one way for saline-alkali soil utilization, but also can improve soil property and maintain ecological balance. Salt-affected soils extensively distribute on the earth. Although the causes are various for salinization occurrence, generally spoken it results from the accumulation of free salts to an extent that causes degradation of vegetation and soils. On the other hand, irrational human practices have increased soil salinity by changing the natural balance of the water cycle in the landscape by allowing excess recharging of groundwater. This reduces suitability to plant growth and increases the potential for other forms of land degradation such as soil erosion and structural decline. Thus salinization is one of the most serious long-term threats to the sustainability of land and water resources in the world. Trees can tolerant a certain level of salinity thanks of the nature. Therefore in the viewpoint of biological amelioration of salt-affected soil, planting trees is necessary and significant. After trees are established in saline land, the watertable could be declined through increasing discharge and decreasing recharge. Additionally total salt content could be decreased, especially in soil surface profile and topsoil as well as soil physical & chemical state could be ameliorated.

Facing the challenge of petrolium price rising and energy consumption increasing, Chinese government has realised how urgently it needs an alternative solution. Under the banner of creating a "harmonious society", the government is looking into new options for sustainable rural development, utilising resources more efficiently, prioritising new and renewable energy technologies with wider market applications. With its vast territory and diverse geographical regions, China has a large stock of biomass resources from agricultural and forest residues, as well as vast areas of saline land that can be used for bioenergy development. In this paper salt-affacted land resources and possible flora resources cultivated for biomass production were approached, as well as strategies to develop these saline soils. The potential of the country's forest-based bioenergy would thus be equivalent to 200 million tons of coal, the utilization of which would reduce the consumption of fossil energy by 10 percent. It is concluded that the potential of biomass production through exploiting saline soils is large ans the prospects in future are bright, too.

Schistosomiasis is a parasitic infection caused by blood flukes (trematodes) of the genus Schistosoma. The intermediate host is an aquatic or amphibious snail (Oncamelania hupensis) . The World Health Organization describes schistosomiasis as 'the second most important (tropical disease) in terms of public health importance' after malaria. It is endemic in 76 developing countries, putting over 600 million people at risk of infection. Over 200 million people are estimated to be infected worldwide, with 20,000 deaths annually. Officials detected 10.58 million square meters of new snail habitats in 2005, up 0.44 percent over 2004 when China had 3.85 billion square meters of snail habitats, according to figures from the Ministry of Health. To be effective, schistosomiasis control strategies should be adapted to the local epidemiological situation and caution must be taken when destroying freshwater snails using chemicals - particularly in terms of impact on the environment. One of the effective practices in China is conducting forestry ecological engineering that focuses on snail control and schistosomiasis prevention through improving environment and refraining snail propagation. Test plot located at Dongting Lake, Hunan province, where usually was most endemic areas. Poplars were planted according to the certain designs, site preparation was done to wipe out weeds and pile up ridges, spacing was 6 m times 8 m, and undisturbed site was as the check. After 12 years, the results indicated that snail density was decreased 85.2%--100% in poplar stands; while for the check, the figure was increased 108.2%--120%, and particularly no infected snail were found in poplar stands. With tree growing up, the number of snails fell. As well, poplars growing added incomes for local farmers. By the experiment, it was concluded that improving environment to reduce the amount of snail was available through forestation in wet beach areas.

At present the whole world is facing the challenge of energy shortage. Developing biomass energy resources is vital. However land area is limited in China. Thus exploiting wild lands to plant fast-growing trees as is biomass energy resources significant. There is land area of 1 200 000 ha in Yellow River Delta region characterized with rich natural resources. Due to the adverse and fragile environment, few trees could grow there. Nevertheless black locust (Robinia pseudoacacia) is one of the main suited tree species for afforestation. To approach its growing state and biomass production the black locust plantation was established and field survey was conducted. Based on the results of standard plot inventory and stem disc analysis, the mean biomass of black locust plantation was obtained, i.e. 166.85 t ha-1. The result suggested that for biomass energy resources production trunks of the tree were main body and played an important role, moreover, the function was enhancing with stand growing.