Many “nogoshi”, i.e., lower sections of the river bank that allow upstream floodwater overflow, have been built on the Jobaru River in Kyushu Island, Japan. The soil strata in the floodplain adjacent to the Yago Nogoshi of the Jobaru River were studied using a Geoslicer. The sedimentary facies and the sedimentary ages of the soil strata were determined using Geoslicer samples. The sedimentary environment of the test site was defined, and soil strata formed by sediments during large floods were identified. The layers below ground level (G.L.) -1.50 to -1.70 m are river channel deposits, and the layers above G.L. -1.50 to -1.70 m are back marsh deposits. The results of radiocarbon dating show that the river channel deposits were formed before AD 1500. The lower layers of the back marsh deposits, which contain a considerable quantify of plant roots, were formed at approximately AD 1600. The upper layers of the back marsh deposits, which contain a small quantity of plant roots, were formed after AD 1600. The time of artificial land alterations was deduced based on the results of the sample analyses.

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The soil water characteristic curve (SWCC) is an important hydraulic parameter for modeling water flow and contaminant transport in the vadose zone. However, direct measurement of the SWCC is still difficult. The Arya and Paris (AP) model estimates the SWCC from particle-size distribution curve (PSD) based on the shape similarity of the two curves. They introduced an empirical parameter, α, used to scale pore attributes from hypothetical formations to natural structures. Several approaches have been used to derive α. However, the calculation procedures of these approaches are either quite complicated or are developed without paying much attention to the physical significance of the soil properties. In the present paper the physically based scaling technique (PBS) was applied to derive α for the AP model. Fifty soil samples, representing a range of textures that include sand, sandy loam, loam, silt loam, and clay, were selected from UNSODA hydraulic property database for calculating α using PBS approach. In addition, nineteen soil samples with different textures were used to verify effectiveness of proposed α values. The results compared with other approaches show that the PBS technique combine with the AP model is a more useful and easier approach to predict SWCC from PSD.

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In 1997, the Isahaya Reservoir was constructed at the innermost part of Isahaya Bay, Japan to prevent natural disasters and to develop water resources for large-scale farm lands. The main purposes of this study were to analyze the mechanisms underlying the water quality changes observed and to collect significant information for water quality management at the reservoir. Observed water quality parameters on chlorophyll-a, suspended solids, total nitrogen, dissolved inorganic nitrogen, total phosphorus, dissolved inorganic phosphorus and chloride ion were analyzed by using a water quality model. It was found that the results obtained from the developed water quality model agreed with the observed data. After calibrating the observed data, a simple sensitivity analysis was conducted to demonstrate the mechanisms of the water quality changes. The major water quality problems were suspended solids that had been resuspended by strong wind and eutrophication due to the enrichment of nutrients. The major mechanisms of water quality changes in the Isahaya reservoir were a coagulation and flocculation by brackish water and the transformation process of phosphorus. The coagulation affected the settling velocity of suspended solids and dissolved phosphorus. It was also revealed that the resolution process of dissolved phosphorus from suspended solids was controlled by the salinity.

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Most paddy fields in Indonesia laid on the lowland area and many of them have not sufficient water ply during the dry period. To maximize the use of land, some farmers planted secondary crops using the available low water table along the coastal areas. Some common plants planted during dry period on the lowland paddy fields corn (Zea mais), soybean (Glycine max), groundnut (Arachis hypogaea), chili pepper (Capsicum annum), tomato Lycopersicum esculentum) and mungbean (Phaseolus radiatus). The use of secondary crops on paddy fields using hallow ground water embedded some potential risks that need to be counted. The study conducted to model the risks ction and market risks) associated with the ground water quality and irrigation application methods on the net urns on several crops under different irrigation treatments and application uniformities. Six crops were analyzed to w the potential return under furrow and border irrigation scenarios. Economic reliability measured in terms of scounted Cash Flow performance of each type of crop. The risk analysis reveals that the three type of crops i.e. mato, chili pepper and groundnut shows stochastic dominances over the other three crops means that the crops are less y than to the other three. The model sensitivity analysis performed to show the influence of input variables to the odel outputs and the result shows the commodity prices, inflation and ground water salinity are most sensitive to nfluence the model output.

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Some researchers have argued that a majority of Japanese have a strong desire to continue living in their current residence. This study hypothesized that some of these individuals, however, may well have a strong desire to change residence when they consider the actual requirements for receiving nursing care in the future. This paper, then, investigates preferences for and constraints on moving to a final residence, given the necessity of nursing care. The data are based on a questionnaire survey conducted among inhabitants of detached houses in suburban Hitachi City which is one of the typical suburban cities in Japan. A McNemar's test and correspondence analysis showed that less than 25% of the inhabitants were relatively certain that they would continue living in their current house in the future, whereas most were likely to change their residence whether they wanted to do or not. Furthermore, the inhabitants faced the necessity of compromising in the selection of their future residence (whether or not this involved a change of residence) due to a sense of being undeserving or out of consideration for their children.

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A rapid urbanization has resulted in more rush transformation of a settlement of low-income migration growth into an urban area. The growth squatter settlement role was influenced through an urban form conflict. Many of these points have been debated over the issue of sustainable urban development plan that has led the way into the urban building density appearance and the phenomenon of its urban area growth effects. The ultimate results depend on an increase in carbon emissions changed over time and its effect on climate change. The real challenged problems are being solved in the developing country, such as Thailand's capital Bangkok. Moreover, an unplanned and low-efficient development projects cause extensive devastating consequences to both urban environment and human beings. Particularly for the low-income people who live in a lowland area are more heavily burdened by environmental risks and unsafe area. Thus, it is imperative for this paper to discover a key issue of low-income migration and settlements on the basis of the measurements which includes: (a) the situation of urbanization driving process forces the low-income settlement growth, and (b) investigate the causes and effects on urbanization in terms of the urban environmental conditions and location system (e.g. sensitivity analysis, risk approaches) using GIS-based Multi-Criteria Decision Analysis (MCA) for calculating the simplify situations of alternative factors and using the Analytical Hierarchy Process (AHP) for weighting the measure of individual participant data. By this approach, it is becoming more feasible to be configured, with the Weighted Linear Combination (WLC) operators. This tool presents the usefulness of the relative important weights for relevant approaches of low-income settlement in consequences of growing cities based on geographic information system (GIS).

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Rural planning and construction carries influential natural, economic, social and cultural connotation. The problem of rural features deficiency has prevailed in current Chinese rural planning and construction practice. Based on the problems revealed in rural planning and construction process in Zhejiang Province in China, the article presented a way of recognizing different rural landscape styles, and put forward guiding ideas and spatial strategies for the planning and construction of rural features, from the perspective of ecological system, production system, and living system (namely “EPL” system). Such research might provide guidance for the current construction of Chinese rural features.

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