After the Special Action Committee on Okinawa (SACO) agreement in 1996, Okinawa Prefecture and multiparty have been developing fundamental reuse plan with landowners and citizen. It was changed several times through expert investigations and discussions among them. 2013 plan has come to the halfway point of it. In the plan, some points, especially preservation policy of green, under ground water, and historical heritage in the base were reached consensus among parties. Despite some preservation policy of green and underground water, it has been missing throughout the water balance model study of this area. When people want to save the under ground water to reply the water demand, generally it needs an investigation of current water balance model and water use. So we started a proposal-based study about this research issues.
 This study aimed to clarify two study objectives. The 1^st goal is to calculate exact a water balance model about approx. 1617ha of the 5 watershed areas, A, B, C, D and E, in Ginowan City where the Futenma Air Station is located in. At first, we calculate each land use ratio by GIS to simulate the amount of underground seepage of the rainfall in these 5 watershed areas. It is as for theoretical value. And the other hands, we also researched the amount of several water springs to calculate the amount of underground seepage of the rainfall in these areas as an observation value. The field surveys were held 60 times at each spring waters by flow speed measurement and positive displacement flowmeter. The observation value is in agreement with the theoretical value that we simulate. The finding and the fixed water balance model will contribute to the huge area planning like Futenma.
 The 2^nd goal is to review the open space plan in Futenma reuse plan to fit water demands in these areas by using our water balance model. Because the today's 70% of Futenma Air Station is covered green, it functions as like watershed protection forest. But according to contemporary Reuse plan, after the developing, the green area will decrease than today's area. According to our data gathered by interviewing to farmers and industrial officers who use under ground water and spring water, today's water demand reaches almost 5-62% per supply from the natural condition. We analyzed the demand-supply water balance after the development, it will show over demand at some springs. And the worse more, there are some struggles between farmers in the dry season by the lack of water supply. This result is very important. Before our research, there is no report of the amount of water demand. It means that the demand-supply balance had not been paying little attention. Thus, we proposed to Prefecture Office and City Office to review the open space plan with considering water demands. We explained our analysis in detail at the closed meeting of them. Then almost of our concepts was accepted in the public plan.
 This study's consequences and contribution are three points. 1) The water balance model of this area is established. 2) The under ground water and spring water demand of this area are calculated. 3) Through continuing discussion with parties, our proposal-based study is accepted in the public reuse plan of Futenma.

 This work was supported by JSPS KAKENHI Grant Number JP24710168.

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 This study aims to find out care points of greening plan in re use plan of Marine Corps Air Station Futenma. Research methods were observed daily spring water flows, multiple regression analysis, analyzed out and in flow characters of each spring waters, and then assuming the subsurface structure.
 At first, by using observed daily value of each spring waters (total 489 times), we developed estimation formulas, which described as form of multiple regression analysis formulas, of daily spring waters and cumulative total value of short & long term precipitation. The results were that these adjusted R2 of estimation formulas are from 0.51 to 0.77, these mean that formulas could give explanations of existing circumstances. These estimation formulas are called response models in hydrology which explains interconnection of amounts precipitation and spring waters.
 On Second, we analyzed out and in flow characters of each spring waters by response models. The results of this step, we got 3 types (subdivided in 4types) of out and in flow characters of each spring waters. Type I is spring waters which explain by constant term mainly. It means that these spring waters gush out stably and constantly, and so, it assumed these spring waters flow out from one depthless and broad tank. (Fig. 6, spring water(3)(6)(9)) Type II is spring waters which explain by influence of long term precipitation mainly. It means that these spring waters flow around from 1to 3 months behind precipitation, like very long and slow pace rivers. So we assumed these spring waters come from small surface area tank or the come from thick Ryukyu lime stones layer(Fig. 8, spring water:(11)(13)). Mixture type I and IIis spring water (8). This spring water has both character of I and II. Type III is spring water influenced by short term precipitation. It means that the spring water flows out comparatively soon after rainfall, within few days. So we assumed the spring water is connected with cave and it works like a underground river.(Fig. 9, spring water:(7))
 Considering our all results, we proposed and discussed to local government and land owners about the point of greening plan in reuse plan of Futenma. 1) Greening plan which located type I, Mixture Type I and II, and watershed C and D should be care for quantitative approach. Because these springs are assumed to be shared a depthless and broad underground tank, every precipitation will be penetrating and finally reach same water basin. So, the point of greening area is not a location but the enough quantity for recharging amounts of spring waters. (Fig. 14 enough quantity greening in the same water basin, watershed C and D, type I) 2) Greening plan which located above the underground water vein, like type II and watershed D and E should be care for on-site approach. Because these springs are assumed be pooling precipitation in the gryke of Ryukyu lime stone layer, if the surface of this site be covered by buildings or be paved, it will be directory influenced to recharge spring water. (Fig. 14 on-site greening above the underground water vain, watershed D and E, type II)
 Conclusion of our proposal-based research is that our proposals were adopted in the official reuse planning as a policy in March 2017.
 This work was supported by JSPS KAKENHI Grant Number JP17K06714.

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本稿は、沖縄県を事例に、地域共同管理と「公共性」の関係を考察することを目的とする。那覇市の北部に位置するは人口約9万の地方都市であり、市域の中央部には普天間飛行場、北部にはキャンプ端慶覧があり、これら軍用地の面積が市域の3割以上を占めている。またインテンシブな事例調査の対象とする宜野湾区は、行政区でありまた自治会の範域でもあるが、戦前の集落をほぼ全面的に普天間飛行場に接収され、戦後あらたに集落を再建した地区である。
とりわけ宜野湾区の住民は、いまも基地と隣り合わせに住み、基地という日常的なリスクと向き合って生活する一方、基地雇用や軍用地料に生活を依存する状態にある。ここにみられるのは、基地に象徴されるグローバルおよびナショナルなレベルの「公共性」の論理の地域社会への浸透であり、および宜野湾区の地域共同管理の課題は「公共性」問題と不可分に結びついている。本稿では、普天間飛行場の返還が日程にのぼりつつあるの事例をとおして、地域共同管理と「公共性」の重層的関係について考察する。

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沖縄県の普天間飛行場周辺に位置する伊佐ウフガー，メンダカリヒーガー，ヒャーカーガーの3地点において，湧水中の有機フッ素化合物（PFAS）濃度と降雨量との関係を明らかにした．伊佐ウフガーでは，30日積算降雨量とΣPFAS濃度（PFOS，PFOA，PFHxS濃度の合計と定義）とに正の相関がみられ，メンダカリヒーガーでは負の相関が認められた．ヒャーカーガーでは明瞭な関係は確認されなかった．これは地下水の流出過程の違いが長期的な30日積算降雨量との関係に反映されていることを示唆する．一方，降雨イベント後には，PFAS濃度は数日程度の短期間のうちに応答し，伊佐ウフガーではΣPFAS濃度が増加したのに対し，メンダカリヒーガーではΣPFAS濃度が低下した．この差異は，湧水地点からPFAS汚染源までの距離に起因する希釈効果によって解釈できる可能性がある．

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沖縄本島におけるミズイモでのオキナワイナゴモドキの発生消長と被害状況を調査した。
1)本種の被害発生圃場率は76.1%で,各地域における被害葉率は4.8～49.2%であった。また被害の全くみられない地点もあった。
2)本種による被害は,3月頃より認められ,8月以降急増し,9月に最も高くなった。その後,被害は急速に減少し,1～2月には認められなかった。
3)本種の産卵穴は4月から認められ,被害葉率が最も高くなる9月には,被産卵葉柄率も最も高くなった。
4)本種は成虫が3月頃,幼虫が5月頃より認められ,幼虫は8月に,成虫は10月に最も多くなった。また成虫が12～3月にかけて葉鞘の隙間で越冬して
いることが確認された。

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