The period of Song and Yuan Dynasties was important for the development of human settlement in JianghanDongting Plain. The number of settlement increased, with its scale extended, and its space distribution expanded fast. A lot of environmental factors influenced the change in human settlements. This paper analyzes the geography, hydrology and the nature resource factors. The basin geography contributed greatly to the bigger settlements located on the fringes of the area. On the other hand, the settlements located in the center of the basin were usually fewer, smaller, and moved faster. Meanwhile, the well-developed river system attracted the majority of settlements distributed along the banks of rivers, where settlements usually occurred along the water transportation lines. In addition, the abundant aquatic resources and mineral resources supported some fishing or mining settlements. The change of settlements reflected the basic harmonious characteristics in the relationship between human and nature of Jianghan-Dongting Plain in SongYuan period. At the same time, the problem also appeared as human activities damaged the environment.

Valley spatial structure study is beneficial for the further development of spatial structure theories based on the concrete region type. Research on urban spatial structure is an important part of valley spatial structure. Taking Hanshui valley as an example, urban scale structure and spatial distribution are studied, and some conclusions are drawn: urban system is relatively perfect, but the urban primacy index is too big, scale distribution is lopsided; urban density is comparatively big, spatial distribution is seriously unbalanced; characteristics along axis direction of urban distribution is obvious. The important characteristics of urban spatial distribution is proved by using difference degree and correlation dimension. Some proposals are put forward for the optimization of urban system such as strengthening bibcock status of Wuhan as primary central urban; building growth triangle in XiangfangShiyanNanyang; developing actively local level central urban and increasing the construction of regional spatial structure axis.

With the development of social productivity, the theory and practice on how to change the relationship between city and country from division to integration have attracted increasing attentions and urbanrural integration will become a basic tendency . In recent years , since the economy develops rapidly and the relation between city and country is becoming increasingly compact, the condition for accelerating urbanrural integration in Chongqing City has been well met. But the urbanrural integration development in this region is being confronted with a series of problems and obstructions originated from economy , policy , nature environment etc. So the new framework of the integration mode must be established . In the future the way to advance urbanrural integration of Chongqing City is to develop economy , adjust the structure of urbanrural space and industry space , at the same time to exert market mechanism and policy enforcement. In the development of urbanrural integration, the urbanrural space of Chongqing City will exhibit“ polycentric cluster structure ” . The strategic emphasis in the promotion of urbanrural integration in Chongqing lies in the realization of urbanrural economy integration, acceleration of urbanrural space interation and the protection of ecological environment.

In the Yangtze Basin, many mount tourism destinations develop well and have successful experience such as implemented by government, emphasizing tourism value, escaping extensive development, conceiving a world-class destination image, keeping good environment, promoting excessive investment, developing grand tourism, upgrading service level. Shennongjia is a typical mount tourism destination in the Yangtze Basin and then can get some inspiration. The strategies are following with the developing trend, forming new development poles, carrying out regional tourism development strategy, integrating RMP system, rebuilding a new tourism image and promoting regional cooperation.

Studies on biological characteristics ,change of catch per boat and maximal sustaining yield (MSY) of Coilia nasus schlegel in the lower reaches of the Yangtze River were carried out during the period from 1993 to 2002.The result showed that average bodylength and bodyweight were 29.19 cm and 94.33 g in fishing season. The correlative equation between bodylength and bodyweight could be expressed as Y= 0.004 8X2.906 9 and the coefficient of fullness was 0.379. The average value of absolute fecundity and relative fecundity were 23 695 eggs/fish and 229 eggs/g body weight respectively, and the diameter of matured egg was 0.77 mm. The correlative equation Y= 0.017 2X4.101 might be used between absolute fecundity and bodylength and it was Y= 305X-5 410.1 for absolute fecundity and bodyweight . Most of the fish were two years old in fishing season. The average value of the total catch per boat was 393.14 kg. Average annual catch was 891.51 t and MSY evaluated by model of Schaefer was 2 061.81 t in the lower reaches of the Yangtze River.Compared with historical data, the miniaturization of the fish was evident and the community age structure tended to be onefold and lowaged,at the same time ,the resource of C. nasus had decreased significantly.

The middle route project which transfers some water from the Danjiangkou Reservoir will decrease the streamflow of the Danjiangkou Reservoir, change the water balance and environment condition of the middle and lower basins of the Hanjiang River. It has an obvious effect on the economic and social development. According to the research on environmental water demand and economic and social water demand, combined with the gray connectedness and entropy, a water resource allocation model based on the theory of gray system theory is developed, providing the system analysis of water resource with a new method. The method is applied to optimally allocate water resource in the middle and lower basins of the Hanjiang River, and its feasibility is discussed with the satisfaction result obtained.

Water resource is not only an important material base for social economic development, but also an irreplaceable natural resource. To realize the magnificent goal,the 16th National Congress of Communist Party of China has proposed to build a welltodo society throughout the country, with water resource being the essential condition. This essay has established a dynamic model to predict the total water requirement in the country over the next two decades through the industry, agriculture and water demand of life. The prediction indicates that the water demand of our country is about 5 500 hundred million cubic meters by 2022 based on project 1,7 400 based on project 2, but the ability of national water supply may reach 650 billion cubic meters by 2020 and the water amount available to supply will be 6 100~6 500 hundred million cubic meters.The result of prediction in project 1 is less than the providing amount and larger in project 2.We are facing austere problems in project 2.

Coastal plain of south Hangzhouwan Bay, central area of the golden economic city triangle made up of Shanghai, Hangzhou and Ningbo, is one of the most developed zones in coastal area in China. The study of its land use and cover pattern dynamics have great significance in the utilization of land resources and sustainable development. In this study, we analyzed the land use and cover pattern dynamics through the interpretation of TM images in 1987 and 2000. The results showed that the areas of land for building, water area and fishery land increased. Paddy field, dry agricultural land, tidal flat, forest land and saltern decreased. Because of the influence of nature conditions and anthropic activities, mean area of patches decreased from 0.245 km2 to 0.173 km2 while density of patches increased from 4.081 pieces/km2 to 5.781 pieces/km2. At the same time, the gross patch numbers had 42% increased compared with that in 1987. Edge density, landscape shape index, fractal dimension and patch density increase variously, but the changes of pattern indexes of land for building is quite different from these types for the urbanization and nonagriculturalization of cultivated land.

As a physical index to express the information of topography in hydrological modeling, topographic index, ln(α/tan β) has a high application value. River Tools and GRIDATB programs are used to compute the spatial distribution of ln(α/tan β) in the small watershed in redsoil hilly region with moderate topography based on DEM. They use D8 and MFD algorithms respectively. The results show that values of ln(α/tan β) computed with the D8 algorithm are more discrete and have rougher pattern than those computed with the MFD algorithm, and the mean values of ln(α/tan β) with D8 algorithm are slightly higher than those with the MFD algorithm. Compared to the D8 algorithm, the variances and skews of the distributions with the MFD algorithm are lower. However, the spatial distribution of ln(α/tan β) values with the D8 algorithm looks similar to that with the MFD algorithm. For some hydrographic models, such as TOPMODEL, the D8 algorithm can be used to compute the spatial distribution of ln(α/tan β) instead of the MFD algorithm.

The amenity value is one of the important part of the whole value for the agricultural land. The ignorance of the amenity value leads to the inefficient allocation of the agricultural land resource. The proper reveal of the whole ecological value is the key issue of the sustainable agricultural land use. At present, our knowledge and study on the amenity value of agricultural land is still in a starting process. In this research, adopting Contingent Valuation Method (CVM), the authors revealed the amenity value of the different types of the land for different usage of agriculture. Based on this, the authors also calculated the total amenity value of the agricultural land in Jiangsu Province through investigating 1 000 persons from different careers and ages with the semistructural questionnaires and the telephone investigations. The whole amenity value for the agricultural land in Jiangsu province reaches 2.5 billion per year. And also, the difference of amenity value among the different types of agricultural land use is also large. Thus, in order to make the better use of the agricultural land, the amenity value should be taken into account in the whole land resource utilization system.

Economic and bionomical benefit can be reached through using controlledrelease fertilizers. The most important application of controlled-release of fertilizer is polymercoated fertilizers. The current research and nutrients release model about polymercoated controlledrelease fertilizer are briefly introduced in this paper. The factors that influence the nutrients release behavior are as followings: membrane thickness, granule radius, diffusion coefficient, nutrients composition and nutrient dissolving property. The application of polymercoated controlledrelease fertilizer in our country is in the initial stage, and almost depends on importation, but shows strong application potential in future with the economic development. Some important progress about the research of polymercoated controlledrelease fertilizer has been made in our country. However, there are also some deficiencies in technological, cooperational and market aspects. Therefore, a commercial polymercoated controlledrelease fertilizer with Chineseowned needs a long time study, especially in the theory research and market development.

The effect of Scirpus mariqueter on phosphorous distribution in intertidal sediments was examined by measuring the phosphorous concentration in nearroot, meanroot and farroot sediments at different depths in three cores, with application of the theory of rhizospherical microbe. The results of the examine indicated that Scirpus mariqueter disturbed the phosphorous distribution by drawing phosphate from sediments and microbial degradation which formed the horizontal and vertical concentrational grads. The purification rate of phosphorous by uptake of Scirpus mariqueter may be 16.7~46.1 mg·cm-2·d-1.

Based on the analysis of the grain size characteristics of the sediment in Nanhui joinit area between Changjiang and Hangzhou bay, the net transport trends in Nanhui area are studied by using “Gao and Collins” model. The results are shown: (1)The trend is similar to the distribution of the grain size parameters including the medium grain size, the sorting coefficient and skewness, where the relationships of three parameters have a strong correlation; (2) The grain size characteristics in Nanhui exhibit positively skewed and poorly sorted with a value concentrated around 2. The distribution regions of the sediment with fine grain size (<0.01mm) are located in Nanhui area except for the regions including medium is distributed sector of Momaosha, Nan Huizui and nearshore zone in Luchao harbor where coarse sediment (>0.01mm); (3) Combined “GaoCollins” mode with the characteristics of the dynamics and sediment in Nanhui, it's indicated that the sediment transport patterns are from the north to the south in East bank, but the sediment transport trends in Nan bank should be further analyzed because of the conditions of the complex dynamics in Nan bank.

Semivolatile organic chemicals and organochlorine pesticides in the Huaihe River, Jiangsu Province were analyzed. Most of the chemicals were in the list of priority pollutants of USEPA. Then, a series of assessments on risk characteristics of organic chemicals in water body and relative proposals were provided. The risk assessment on these forty\|eight organic chemicals in the Huaihe River was conducted, according to the value of human health for consumption of water and organism in USEPA′s national recommended water quality criteria on priority pollutants and non\|priority pollutants, plus IARC's index of carcinogenicity. The results showed that the concentration levels of eighteen chemicals among them exceeded EPA′s critical standards, while nine of them were in need of special concerns. Among the special nine pollutants, however, eight of them, including Hexachlorobenzene, NNitrosodiNpropylamine, 3,3dichlorobenzidine, 2,4,6trichlorophenol, 2,3,4,5,6pentachlorophenol, indeno(1,2,3cd) pyrene, 4,4′DDT and Heptachlor were in need of concern while another chemical: dibenz (A,H)anthracene be of special concern. The sources of these chemicals were discussed and some control strategies were suggested based on the risk assessment.

The behavior of light in water, particularly its attenuation with depth, has important ecological and water quality implications. The underwater light climate ultimately determines the depth distribution, abundance and primary production of phytoplankton and macrophyte. Light attenuation is regulated by the composition and concentration of various attenuating constituents, which include water itself, gelbstoff, phytoplankton and tripton. Here the vertical attenuation coefficients of downward visible irradiance were measured in 10 different stations in Hangzhou West Lake using 192SA and 193SA light sensors and a SR9910PC scanning spectroradiometer at the water surface and at different depths. Water chemistry variables such as total suspended solids (TSS), organic suspended solids (OSS), inorganic suspended solids (ISS), chlorophylla (Chla), dissolved organic carbon (DOC), absorbance of chromophoric dissolved organic matter (a) were measured to determine the relative contribution of dissolved and particulate components in explaining the variation in diffuse attenuation coefficients.The attenuation properties of Hangzhou West Lake vary greatly though it is a small shallow lake. The main attenuators such as TSS, Chla and DOC vary from 3.68 to 42.76 mg/L, 4.64 to 85.95 μg/L, 5.19 to 9.22 mg/L, respectively. CDOM absorption coefficients at 440 nm are in the range of 0.30～1.46 m-1. PAR attenuation coefficients range from 1.13 to 6.04 m-1 with an average value of 4.00±1.69 m-1, the corresponding euphotic depth ranging from 0.76 to 4.08 m with an average value of 1.54±1.11 m. Only small south lake and Maojiabu lake regions the euphotic depths are larger than water depths. Therefore, the restoration of macrophyte is difficult under present underwater light condition and water level. Based on regression analysis between PAR attenuation coefficients, euphotic depths, secci disc and main light attenuators, phytoplankton and organic suspended solid play a main role in regulating the attenuation of light.

The effect of a floatingleaved macrophyte Trapa quadrispinosa Roxb on nitrogen resuspension from sediment was studied with sediment traps placed within (inner zone) and outside (outer zone) of the macrophyte stand in Lake Taihu. During the study period, the average sediment resuspension rate was 658.13 g dw m-2 day-1 in outer zone and 218.46 g dw m-2 day -1 in inner zone; With the resuspended sediment, 1 560.96 and 718.06 mg N m -2 day -1 was brought to the water column in outer zone and in inner zone respectively, suggesting that the nutrient loading due to sediment resuspension was considerable high in Lake Taihu. The results also revealed that the total nitrogen concentration of the upper sediment had a negative relationship to the sediment resuspesion rate. Thus it could be concluded that floatingleaved macrophyes are able to reduce nutrient resuspentsion significantly from sediment.

Based on the data from Nanjing statistical yearbooks, a variety of the ecological footprint indicators, including per capita ecological footprints, per capita ecological carrying capacities and ecological deficits of the Nanjing region in the period from 1992 to 2002 was calculated in this study, by the use of corresponding methodology. Furthermore, dynamic changes of the indicators mentioned above during the past 11 years were analyzed. First of all, the data obtained indicated that, the per capita ecological footprint of the Nanjing region was much higher than the average of Jiangsu Province, and even 1 time higher than nation level of China measured in 1997. Meanwhile, the ecological carrying capacity of the Nanjing region was comparatively much lower, and the ecological deficit in the year 2002 even reached the area 20 times bigger than Nanjing territory. The figure of the per capita ecological footprint was already beyond the global ecological critical value 2.0 hm2 per capita, suggesting a great pressure on the local natural resources and ecosystem and a serious challenge to Nanjing regional sustainable development. And, along with rapid local economic growth driven by urbanization and industrialization, the ecological footprint and ecological deficit kept increasing, while the ecological carrying capacity was decreasing in the Nanjing region during the period from 1992 to 2002. For a better future of sustainable development, therefore, the strategic measures such as highefficiency utilization of energy sources, environmentalfriendly development of natural resources, effective control of population growth, and persistent conservation of arable lands as well should be carried out. The gray model was used to predict the average ecological footprints and ecological carrying capacities from 2003 to 2005. The results were credible.

Urbanlization makes more cities and larger cities. City is the part has been changed by people.City has special regional environment. The heatisland, the inner part of the city temperature higher than the around of the city, is one of the most important city environment problems which was intensively concentrated and studied. Nanjing is one of the biggest cities along the Yangtze River. The heatisland of Nanjing is obvious, but it was rarely studied. This paper used two temporal MOIDS band 31 data to make the temperature brightness scene of Nanjing. The area and distribution of heatisland of Nanjing were analyzed based on temperature brightness scene. The average value and standard deviation value of the temperature brightness scene and comparative brightness temperature were used as the index to evaluate the intensity of heatisland of Nanjing. The two temporal temperature brightness scenes were also contrasted, and the differences of the two is obvious. Because the MODIS data has very high temporal resolution and is freely received in real time, it can be used to monitor urban thermal field.

The karst area of West Hunan is a typical karst rocky mountain in Southwest China, and its ecoenvironment influences greatly the building of national economy. The chief task of maintaining sustainable development is to rehabilitate the vulnerable karst ecoenvironment. Dalongdong karst platform is one of the minority habitats where soil is poor and water resources are difficult to be exploited. Some facts, such as low vegetation covered rate, short surface water, deep ground water level, rocky desertification and soil erosion restrict seriously the development of local economy. By studying the characteristics of physical geography, geologic-tectonics, karst water resources, land and vegetationenvironment in Dalongdong Cave karst drainage basin, the ecoenvironment problems, such as rocky desertification etc, are analyzed and rehabilitation measures are proposed as well in this paper.

In this paper, analysis of the current pollution status and integrated quality of Le′an river was carried out on the basis of recent hydrology, water quality, and pollution source investigations. It was summarized that the main water pollutants were CODCr and NH3N, with the major pollution source being from farming and livestocks and municipal wastewater. Based on the above described facts, water environmental control targets have been proposed, and a collective idea was put forward that is to control the effluent with the discharging standard, to build wastewater treatment plant, to control notpoint pollution sources, to restore ecosystem , and to improve the supervision and administration on items of Le′an river water environment.

Principal component analysis (PCA) was used to study the antierodibility of forest soil in 4 typical forests (mixed wood, broadleaf forest, bamboo forest and shrub forest), compared to arable land soil, in Jinyun mountain, Chongqing City, in Three Gorges Reservoir Areas. The result shows that the 13 anti erodibility indexes can be scaled down to the 7 optimal indexes. PCA comprehensive exponent of antierodibility indexes shows that the order of antierodibility: shrub forest (45.51) > mixed wood (41.94)>broadleaf forest (32.65)>bamboo forest (23.35), and that the antierobility of soil in Jinyun mountain is in decreasing trend from topsoil to bottom soil (49.32, 41.86, 32.03, 27.11). The 19 soil samples in all soil layers in different land use types can be classified in to 3 sorts with different antierodibility on the basis of fuzzyclustering analysis.

Based on the preliminary investigation in Three Gorges Reservoir (TGR) from 12th to 17th of Oct. 2003 and 17th to 21th of Apr. 2004, this paper studied the aquatic environmental characters at early reserving stage of TGR. The results showed that the exchanging capacity of water body is weakened, organic pollution is relatively light, the concentrations of TN and TP are both quite high which met well enough to algae bloom in TGR and the integrative trophic state of reservoir is medium. According to the variation of the aquatic environmental characters, the water body of TGR could be divided into three kinds of reaches, namely the water fields before the dam, the mainstream reach in the middle reservoir, and the tributary reaches of reservoir. In account of the high concentrations of TP and TN, the authors justified that both water temperature and water velocity are the main causal factors in influencing the characters of river reaches in all 3 aspects. Considering the sensitivity of eutrophication of 3 different reaches, the authors found evidently that it is sensitive in both the water fields before the dam and the tributary reaches of reservoir, but relatively low sensitive in the mainstream reach in the middle reservoir because of the relatively high water velocity.

A large scale of waterpower projects have been and will have been constructed in the main upper and middle reaches of Yangtze River and its tributaries. According to the completed plan and construction step cascading reservoirs along these rivers will appear in future 20~30 years. Based on hydrological observation and data collected over last 20 years the change of water flow and sediment in Yangtze River and their occurrence reason were analyzed. With some observations to a few completed reservoirs,the impact manner and degree of sediment transportation rule were discussed. Finally some measures and proposals to decrease environmental effect as cascading reservoirs were suggested. It appeared that the flow and sediment process have changed, and sedimenttransporting quantity have obviously reduced in most river channels. Cascading reservoirs are one of the most important factors inducing the decreaes of sedimenttransportation . Cascading reservoirs not only decrease sediment transportation and runoff, but also significantly change natural water flow and sediment process. All of these may influence the environment of middle , down streams and estuary of the river. In order to reduce the effect on river features after the completion of cascading reservoirs, it is necessary to change the way in which the river is exploited for hydropower and is manipulated for flood control. Using flood to scour sediment and optimizing cascading reservoirs regulation will maintain nature river at a possibly natural condition.

In recent years, the agricultural nonpoint pollution has threatened the water quality protection of headwater area in reservoir. To prevent the environmental pollution, protect the water quality of the ground water body,and to exert enough the productive potentialities of resources, it is important to control nonpoint pollution in the protection zone of headwater area of a reservoir at present. Pretank technology is one of the effective ways to prevent the nonpoint pollution in headwater area of reservoirs because it has such advantages as low expenses, suitable for many kinds of conditions. According to the special geographical characters and some characters of the nonpoint pollution in headwater area of reservoirs, this paper explains the composition of pretank and its water quality purification mechanism, proposes the capacity of a reservoir and site selection for pretank,and analyses detailedly pretank ecosystem and aquatic biological construction. Furthermore, this paper put forward the limitation of pretank in the course of usge. Owing to pretank technology which can reduce pollution load organically outside reservoir, especially the nitrogen, phosphorus in the stream that flows into reservoirs, this technology has extensive potential application prospects.

The authors used the elastic packing for biofilm and fine bubble aeration for oxygen enrichment in the system of biological contact oxidation to rehabilitate the slightly polluted Chuanyang River in Shanghai. Parameters of water quality in Chuanyang River were as follows: turbidity 90～300 NTU, NH+4-N 0.5～10.0 mg/L, CODMn 4.0～10.8 mg/L, and pollution index 2～8. Establishment of biofilm was successful within seven days with the influent water having a concentration of NH+4-N 2.6～3.1 mg/L and temperature 20℃～22℃. The removal rates of NH+4-N was more than 90％. The authors washed the packing and removed the sludge periodically in order to avoid the occurrence of anaerobic condition in biofilm that would decrease the removal rate of the pollutants. Under the normal condition of biorehabilitation,i.e. HRT 1.3 h, DO 7.5～10.2 mg/L, the ratio of gas to water 0.5, The authors observed a biophase enriched with the bacterial species of various physiological characteristics (aerobic, heterotrophic, and autotrophic). The biofilm thickness was in the range of 0.09 to 0.13 mm and increased with decreasing NH+4-N of raw water. Due to the adequate concentration of dissolved oxygen, the rates of mass transportation and thus NH+4-N degradation were rapid. So,about 90% removal of NH+4-N was achieved within an hour.

Most districts of Panzhihua are high danger areas of debris flow. Those counties dominated by Panzhihua were formerly endangered by debris flow. Till now, many towns, mine areas, power plants and traffic establishment are threatened by debris flow. The debris flow gullies in this area are distributed in zones of Annin, Jingsha and Yalong rivers, which have the characteristics of developed fault, strong rock weathering and frequent rainstorms. Based on the statistics of development conditions of about 200 debris flow gullies, The authors found that the gully ratio of slop, drainage area, main gully length, gully form factor and the relative altitude have the nonlinear properties on the spatial distribution, which also have a good nonlinear correlation with corresponding debris flow gullies. It is shown that the evolvement of debris flow has selfsimilarity. Among these factors given above, the values of the gully ratio of slops and the drainage area are the least. This illuminates that the gully ratio of slops and the drainage area could control the form and progress of debris flow. These phenomena also reveal the nonuniformity and selfsimilarity of debris flow gullies development on certain degree.

It is bound to be a trend in flood control and hazard mitigation that the study object of flood disaster risk converts from single risk to integrated risk. So, the constitution characteristics analysis of integrated risk for flood disaster is the allimportant role. At first, by applying the theory on Disaster Science，the macroconstitution of integrated risk for flood disaster, which is composed of the hazard of flood, absoluteness in frangibility of environment, relativity in vulnerability of disaster carrier and evaluation for the situation of a disaster loss for the sake of macroevaluation for flood disaster risk, is presented. The corresponding quantitative approaches of them are constructed too. Second, from the point of view of model, the microconstruction of the risk chain, which consists of flood risk, engineering risk, investment risk, floodplain risk, flood ecoenvironment risk and decisionmaking risk for flood control, is structured regarding flood as the center. The corresponding quantitative conceptual model are constructed by Probability Theory. Besides, systemic analysis on the constitution of integrated risk has been carried through in the end.