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Grant amount：\13130000 （ Direct Cost: \10100000 、 Indirect Cost：\3030000 ）

In this research, we determined the actual concentrations of pharmaceuticals and personal care products (PPCPs) in sludge of rural sewerage and the control measures for depression of the PPCPs concentrations in the crops applied the sludge. For the depression of the PPCPs concentrations in sludge, long retention time and aeration in the sludge storage tank in rural sewerage are effective. In the drying and compost process, longer treatment time and higher treatment temperature leads to the promotion of PPCPs degradation. The farmland soil containing the high concentration of organic matters have high adsorption capacity and biodegradation ability for PPCPs. Root vegetables tend to have higher PPCPs concentration than leafy vegetables. These findings would be valuable for the control the PPCPs concentrations in the crops applied the sludge.

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Grant amount：\16380000 （ Direct Cost: \12600000 、 Indirect Cost：\3780000 ）

We developed a rearing system for hard-coral and Halimeda spp. (green macroalga) using LED light and artificial seawater in the laboratory. We used this system for ecotoxicolgical studies on Acropora spp. (hard-coral) exposed to low concentrations of Irgarol 1051 and Diuron (1 and 10 μg/L). Measurement of RGB values (R, red; G, green; B, blue) and delayed fluorescence using a high sensitivity luminometer showed that Irgarol 1051 is more toxic to Acropora spp. than Diuron. Exposure to Irgarol 1051 at the concentrations used induced loss of body colour in Acropora, and bleaching within 2 weeks. The RNA-seq analysis revealed the potential for up- and down-regulated genes in Acropora tenuis by exposure to these herbicides.

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Grant amount：\14170000 （ Direct Cost: \10900000 、 Indirect Cost：\3270000 ）

Some transformed products of pharmaceuticals (TPs) often have adverse effects on aquatic ecosystem and human health. In this research, the actual TPs concentrations in the reclaimed wastewater of rural sewerage and in the water in the paddy field applied with the reclaimed wastewater were clarified. We found that it is very effective for depression of the TPs concentration to keep the high bacterial concentration in the treatment tanks in rural sewerage, the long water retention time in the paddy and so on, because the biodegradation and photodegradation are enhanced in the conditions. These findings will contribute to the high safety of the rural sewerage reclaimed water for aquatic ecosystem and human health and the reliability of the water purification function of the paddy irrigated with the reclaimed water.

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Grant amount：\5070000 （ Direct Cost: \3900000 、 Indirect Cost：\1170000 ）

We measured strontium isotope ratios (87Sr/86Sr) and concentrations of trace elements of irrigation water, drainage water and soil extracted water. Results showed that those concentrations increased from upper stream to downstream.
The 87Sr/86Sr ratios of soil extract of water and acetic acid showed positive relationship, and the ratio of each sampling point showed distinctive value. The data showed salt origins of sampled soils changed from upper stream to downstream; sea water salt were replaced by that from irrigation water and other anthropogenic inputs in the study area. Therefore, the measurements could be applicable to analyze salinization and desalinization process in irrigated soils from past to present.

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Grant amount：\3770000 （ Direct Cost: \2900000 、 Indirect Cost：\870000 ）

In this research, the actual condition of the contaminations of 15 kinds of the pharmaceuticals and personal care products (PPCP) were determined in rural river in Japan. PPCP is the emerging contaminants for the aquatic ecosystem and human health. The research results show that the PPCP concentrations were similar or higher than in urban rivers in Japan, where the coverage of the domestic wastewater treatment plant (rural sewerage) was low. The results also indicates that the rural sewerage is a quite effective infrastructure to the depression of the PPCP concentrations in rural rivers in Japan.

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Grant amount：\13130000 （ Direct Cost: \10100000 、 Indirect Cost：\3030000 ）

In this research, it was suggested that the rural sewerage treatment plants have high removal function of pharmaceuticals, especially for the plants employing the activated sludge process. While the various kinds of pharmaceuticals were detected in the treated wastewaters in the actual rural sewerage treatment plants, the concentrations were not over the critical level for aquatic ecosystem. Ketoprofen (nonsteroidal anti-inflammatory drug) had the highest risk, however, in 15 pharmaceuticals measured in this research. The paddy field which irrigated with treated wastewater had the purification function for the almost all of the 15 pharmaceuticals including Ketoprofen. In the investigated field, the pharmaceuticals accumulation with time in paddy soil and the pharmaceuticals movement to the edible parts of rice plant were not observed. These results suggest that the non-diluted reclaimed wastewater irrigation for paddy is valuable technique for environmental protection for aquatic ecosystem surrounding wastewater treatment plants.

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Grant amount：\4550000 （ Direct Cost: \3500000 、 Indirect Cost：\1050000 ）

Non-diluted actual advanced treated wastewater with the stable isotopes (^<15>N,P^<18>O_4) as the tracer was applied to the rice plant in pot-scale experiments. The experiments were conducted under the variety of condition of fertilizer application rate, kind of soils, and soil permeability. In the research, the nitrogen and phosphorus dynamics in the pots and the effect of the treated wastewater to rice plant growth were elucidated. The effect of cations (K, Na, Ca, Mg) and SO_4 in the treated wastewater was also defined. These results show the significant advantageous effect of applying the advanced treated wastewater to rice plant and the suitable condition of the application to obtain the effect.

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Grant amount：\9300000 （ Direct Cost: \9300000 ）

In this research, the basic properties of bamboo charcoal as the soil improvement matter were defined. Main findings were described below. 1) Small electric furnace was developed, and the bamboo charcoals having the fine homogeneity were made under 400-1,000℃. 2) By SEM, it was defined that the density of the vascular bundle was higher in the lateral area of bamboo. Small cells were detected near the bundle. The wall of the cell had the micro pores with 0.1-0.5 μ m diameter only in inner area. The micro pores could not detected in the wall of the cell and on the boundary of the vascular bundles. These results indicate that the bamboo charcoal provides the wide variety size of the pores for bacterial habitation. 3) The higher the carbonization temperature was, the higher the conductivity of the charcoal was achieved. The conductivity can be utilized as the indicator of the refining degree. 4) Under the carbonization temperature as 400-700℃ the carbon crystallization or the connection of the graphite was promoted, which led to the sudden contraction and the increase of the true density of charcoal. In this process, the ash solubility increased, and the increase promoted the pH raising and ion leaching, in connection with the development of the specific surface area, ion exchanged capacity, and the graphite structure. Under 800-1,000℃, the ion exchanged capacity and the ion leaching increased, conversely, the specific surface area decreased. Under 700-800℃, the specific surface area, the ion exchanged capacity and the ion leaching were the largest. The potassium leaching was larger than other ions. From these results, we concluded that the bamboo charcoal, especially the charcoal made in 700-800℃, is most available as the soil improvement matter having the effect of the fertilizer adsorption, the neutralization of the acid soil, and the potassium fertilizer. These effects lead to the increase of bamboo consumption and provide the improvement of the bamboo forest, the rural environment, the rural landscape and amenity, and regional resources.

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Grant amount：\5300000 （ Direct Cost: \5300000 ）

Firstly, the review of the research was conducted. Secondly, in order to define the actual status of the reuse of the treated wastewater from rural sewerage for agriculture, representative 18 rural sewerage and 4 public sewerage were investigated. Main findings are : 1) The main purpose was the prevention of the water shortage. Fertilizer effect of the treated wastewater and the water purification function of the farmland were not considered. 2) The treated wastewater was mainly utilized for paddy fields. 3) In many cases, the reuse were practiced throughout the irrigation season every year. 4) The sending systems of the treated wastewater for the farmland were very diverse. 5) The planning conditions of treated wastewater were determined without the consideration for the reuse. 6) A wide variety of treatment systems was employed. The problems for these conditions of the reuse were also defined. Thirdly, investigations of the "O area" in Ehime prefecture were conducted, where the treated wastewater reuse for paddy fields was actually practiced. In the area, the treated wastewater was diluted in the irrigation pond or by river water. Main findings are : 1) The reuse resulted in the ordinary harvest of rice plants under the general conditions of the fertilization and the utilization of agricultural chemicals. 2) The number of coliform groups and heterotrophes in treated wastewater were smaller than the natural water in this area : e.g. river water. 3) The purification function of paddy fields were effective for NOx-N.4) The sending of the treated wastewater to the pond resulted in the increase of the volume of over flow water. This condition led to the reduction of labor for management of the water gate of the pond. 5) The treated wastewater sent to the pond were tended to be not completely mixed and to be remained in the depth of 1-2m in the summer season. The reason of the retention was also clarified.

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Grant amount：\7900000 （ Direct Cost: \7900000 ）

Field studies were carried out on the following two problems, which related to the self-purification function of rural area.
1. The quantitative evaluation of self-purification function of paddy field in polder land.
(1) The pollutant which discharged from paddy field in the puddling stage sediments in the main drainage canal for a time, and then flush out by the drainage of heavy rain.
(2) The effect of biological treatment could not be expected in the main drainage canals and water purification pond even if its retention time is long enough, and the effect of sedimentation is obtained only for 8。ォ24 hours of retantion time.
(3) As a result of calculating pollution load reduction effect by the water purification pond using L-Q equation, it was estimated that the 50% of pollution load could be reduced on all water quality items for irrigation period, and also 20。ォ30% of COD, T-N and 60% of T-P could be also reduced in non-irrigation period.
2. The effects of reuse of treated water of rural sewerage
Survey was carried out in the rural sewerage treatment plant in Iyo City, Ehime Prefecture. It was shown that the NOx-N concentration was reduced, though there were any rise at the COD, T-N concentration, and it demonstrates the purification function of paddy field. It means that the reuse of treated water of rural sewerage is effective measures as water purification method which utilized the self-purification function of the farmland.

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Grant amount：\7500000 （ Direct Cost: \7500000 ）

In the integrated rural development project, to accomplish the comfortable living environment and the active rural community conserving natural environment and rural landscape are the important subjects. For these purposes, the planning methods for rural land use and rural development were discussed in this study, taking into account the rural environment for human and nature. The results are as folows :
1) The integrated rural development plan of Yamada-cho, Kita-ku, Kobe city was discussed from the view point of the conservation of rural landscape and natural environment. In the discussion, the necessity of land use control considering the intentions of inhabitants was shown and the land use plan based on the new regulations of zoning was proposed.
2) The rural landscape plan was discussed in the irrigation canal of Kitagata, Ibigawa-town, Gifu prefecture. In the discussion, several problems are cleared such as the importance of maintenance system, security of discharge in non-irrigation period and consideration of safety.
3) From the field study of the projects in which the natural environment and rural landscape were considered, several problems were cleared such as usual maintenance, practical usage after the project, consideration of safety, planning system by inhabitants, meterials and methods for conservation of ecosystems and so on.
4) Present situations and problems of allotment garden and its classification were shown, and the conception of the consolidation were discussed in Yamada-cho as an example.

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Grant amount：\900000 （ Direct Cost: \900000 ）

嫌気性ろ床槽と接触曝気槽を直列に配置した実験装置を6系列用い、鉄ろ材嫌気性ろ床法でのリン除去の長期的安定化を目的とした比較実験を行った。そのうち1系列(RUN1.)は対照系列とし、通常の鉄板を用いて一般的な鉄ろ材嫌気性ろ床法の運転方法で実験を行った。他の2系列では、数か月に一度の割合で鉄板を嫌気槽から引き上げて大気中にさらし、その暴露時間に2時間(RUN2.)、24時間(RUN3.)と差をつけて実験した。別の2系列には、鉄板に銅版を接着したものをろ材として用い、鉄と胴の表面積比に約4:1(RUN4.)、約3:2(RUN5.)と差をつけて実験した。残りの1系列(RUN6.)では、一日のうち連続した3時間の曝気を行った。その結果と考察の概要は以下の通りである。1.RUN6.以外の系列では、実験開始当初にリンはあまり除去されなかったが、経時的にリン除去率は徐々に上昇した。2.RUN1.2.3.のリン除去率は、前述1.のような傾向が約1.5ケ月継続した後に安定した。しかし、その後RUN1.では、リン除去率は徐々に低下する傾向が見られたが、RUN2.3.では、そのような傾向は全く見られなかった。3.RUN4.5.のリン除去率は、今回の調査期間内では未だ上昇傾向にあり安定しなかった。その経時的な上昇速度はRUN4.の方が大きかった。4.RUN6.では、実験当初は比較的高率のリン除去が得られ、その後、除去率は一時的に低下したが、再び上昇して安定するという、鉄ろ材接触曝気法と同様の傾向が見られた。その後、除去率はやや低下傾向にあったが、この原因は生物膜の肥厚によるものと考えられた。5.以上のことから、鉄ろ材の空気暴露については、リン除去率を長期的に安定させる効果が確認できたと言えよう。しかし、その適切な時間や実施間隔についてはまだ十分に明らかでない。鉄と胴との合板ろ材の使用や一時的曝気が有効な可能性は十分にあるが、今後さらに検討が行われることが望まれる。

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Grant amount：\1400000 （ Direct Cost: \1400000 ）

The contact aeration process with anaerobic filter tanks is frequently used in small-scale wastewater treatment plant in rural areas. In this study, the experiments were carried out in the actual and the model plants, and the Quantification analysis was also used in order to find the appropriate operating method for the nitrogen removal of this process. The results are as follows:
1)When large Metazoa such as asellus and physa have bred in large quantities on the contactors of aeration tanks, they have an unfavorable influence on the progress of nitrification.
2)Since the mass breeding of large Metazoa used to occur periodically from autumn to winter, it is important to prevent their mass breeding in autumn.
3)The back washing of the contactors can restrain their mass breeding to some extent, but the stopping of aeration of two days is needed to control them perfectly.
4)To advance the nitrification in the aeration tanks, operating attention should be paid to many factors, such as water temperature, DO concentration of aeration tank, BOD loading of aeration tank, returned water ratio, specific surface area of the contactors.
5)Discontinuation of aeration less than four hours in midnight of no inflow can save energy without deterioration of the treatment.

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Grant amount：\6800000 （ Direct Cost: \6800000 ）

There have been various methodologies of regional analysis developed for their applications to regional planning. However, these techniques are designed for individual purposes and hardly related to each other. The present study is aimed at the development of a comprehensive software package called "Regional-planning Support System", which integrates certain approaches of regional analysis in various aspects toward an efficient, well-managed system of regional planning.
In the study, computation programs for some of the important procedures in regional analysis, namely, regional classification, population projection, transportation and water system analysis, are developed as sub-modules of the software package. These modules are then applied to a case region in Miyagawa river basin, Mie Prefecture, and the results are examined for improving the support system toward practical uses.
It is important for regional planners to arrange the outputs of various regional analysis appropriately so that the results can be properly reflected to the planning processes. In this meaning, visual expression of the analytical outputs is considered effective. Therefore the present system is constituted with stress put on graphic processing techniques.
The present study has only developed some sub-systems of the Regional-planning Support System as its framework, and not yet reached the completion of the whole system. In the following studies, more efforts should be carried out to improve the System, introducing the concepts of Geographic Information System (GIS) and graphical user interfaces.

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Grant amount：\900000 （ Direct Cost: \900000 ）

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Grant amount：\600000 （ Direct Cost: \600000 ）

小規模汚水処理施設における安定した処理機能の向上と、窒素・リン同時除去のための新しい高次処理方式を確立することを目的として、回分式間欠曝気法による窒素除去と、鉄接触材を使用したリン除去を組み合わせた窒素・リン同時除去法について、これまでに室内実験と現地実証試験を行ってきたが、今年度はその結果に基づいてシミュレ-ションによるモデル化を行うとともに、生成汚泥中の養分の容出と移動について検討した。
シミュレ-ションモデルとしては、BODの酸化分解を一次反応式で、硝化及び脱窒反応を0次反応式で近似させた。現地試験の結果から反応速度定数を求め、BOD=150mg/l、T-N=10mg/lの生活雑排水の処理に適用した結果、T-N除去よりもBOD除去が律速となること、目標処理水質をBOD=20mg/l、T-N=5mg/l、処理水量を100m^3/日とすると、必要槽容量としては37.5m^3程度のもの2連で十分であると考えられた。
次にT-P除去については、鉄筋単位表面積当りのリン除去量は0.33g/m^2であり、流入水T-Pを2mg/l、処理水T-Pを0.5mg/lとすると、必要鉄筋総延長は2.274mとなることがわかった。鉄筋の必要経費は約52万円で、これを5年毎に交換するとすれば年間約10万円、汚水1m^3当りでは2.9円程度と推定された。
最後に、汚泥中の各種養分の溶出や移動についてカラム試験を行った結果、本処理法による汚泥を用いた場合は通常汚泥のコンポストに比べてリンやアンモニアの溶出が多く、特に7週目までリンの溶出が認められた。本処理法による汚泥は有効態リンの含有量が大きく、また有害な貴金属類の含有量が少ないので、安全なリン資材として有効に利用しうるものであることがわかった。

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