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Hydrological extreme events are generated by different sequences of hydrometeorological drivers, the importance of which may vary within the sample of drought events. Here, we investigate how the importance of different hydrometeorological driver sequences varies by event magnitude using a large sample of catchments in Europe. To do so, we develop an automated classification scheme for streamflow drought events. The classification scheme standardizes a previous qualitative drought typology and assigns events to one of eight drought event types—each characterized by a set of single or compounding drivers—using information about seasonality, precipitation deficits, and snow availability. The objective event classification reveals how drought drivers vary not just in space and by season, but also with event magnitude. Specifically, we show that (a) rainfall deficit droughts and cold snow season droughts are the dominant drought event type in Western Europe and Eastern and Northern Europe, respectively; (b) rainfall deficit and cold snow season droughts are important from autumn to spring while snowmelt and wet‐to‐dry season droughts are important in summer; and (c) moderate droughts are mainly driven by rainfall deficits while severe events are mainly driven by snowmelt deficits in colder climates and by streamflow deficits transitioning from the wet to the dry season in warmer climates. These differences in sequences of drought generation mechanisms for severe and moderate events suggest that future changes in hydrometeorological drivers may affect moderate and severe events differently., Key Points: We develop a standardized and objective classification scheme for streamflow droughts using hydroclimatic information. The most severe drought events are governed by other processes than moderate events. Moderate droughts are dominated by rainfall deficits and severe droughts by snowmelt deficits or prolonged rainfall deficit droughts., Deutsche Forschungsgemeinschaft http://dx.doi.org/10.13039/501100001659, EC/H2020/PRIORITY 'Excellent science'/H2020 European Research Council http://dx.doi.org/10.13039/100010663, https://www.bafg.de/GRDC/EN/02_srvcs/21_tmsrs/riverdischarge_node.html, https://doi.pangaea.de/10.1594/PANGAEA.887470, https://cds.climate.copernicus.eu/cdsapp#!/dataset/reanalysis-era5-land?tab=overview, http://www.hydroshare.org/resource/77114d4dfdfd4dd39e0e1d99165f27b3

Importance of evaluation of global hydrological models (gHMs) before doing climate impact assessment was underlined in several studies. The main objective of this study is to evaluate the performance of six gHMs in simulating observed discharge for a set of 57 large catchments applying common metrics with thresholds for the monthly and seasonal dynamics and summarize them estimating an aggregated index of model performance for each model in each basin. One model showed a good performance, and other five showed a weak or poor performance in most of the basins. In 15 catchments, evaluation results of all models were poor. The model evaluation was supplemented by climate impact assessment for a subset of 12 representative catchments using (1) usual ensemble mean approach and (2) weighted mean approach based on model performance, and the outcomes were compared. The comparison of impacts in terms of mean monthly and mean annual discharges using two approaches has shown that in four basins, differences were negligible or small, and in eight catchments, differences in mean monthly, mean annual discharge or both were moderate to large. The spreads were notably decreased in most cases when the second method was applied. It can be concluded that for improving credibility of projections, the model evaluation and application of the weighted mean approach could be recommended, especially if the mean monthly (seasonal) impacts are of interest, whereas the ensemble mean approach could be applied for projecting the mean annual changes. The calibration of gHMs could improve their performance and, consequently, the credibility of projections., BMBF, JSPS KAKENHI, NSFC

The Paris Agreement marks a significant milestone in international climate politics. With its adoption, Parties call for non‐ and sub‐state actors to contribute to the global climate agenda and close the emissions gap left by states. Such a facilitative setting embraces non‐state climate action through joint efforts, synergies, and different modes of collaboration. At the same time, non‐state actors have always played a critical and confrontational role in international climate governance. Based on a systematic literature review, we identify and critically assess the role of non‐state climate action in a facilitative post‐Paris climate governance regime. We thereby highlight three constitutive themes, namely different state‐non‐state relations, competing level of ambition, and a variety of knowledge foundations. We substantiate these themes, derived from an inductive analysis of existing literature, with illustrative examples and propose three paradigmatic non‐state actor roles in post‐Paris climate governance on a continuum between compliance and critique. We thereby highlight four particular threats of a facilitative setting, namely substitution of state action, co‐optation, tokenism, and depoliticization. Future research should not limit itself to an effective integration of NSSAs into a facilitative climate regime, but also engage with the merits of contestation. This article is categorized under: Policy and Governance > Multilevel and Transnational Climate Change Governance, Three constitutive themes—different state‐non‐state relations, levels of ambition, and knowledge foundations—define the multiple roles non‐ and sub‐state actors can occupy in the post‐Paris climate governance regime. Yet, calls for voluntary, collaborative, and synergetic non‐state climate action in a facilitative post‐Paris climate governance setting run the risk to overshadow fundamental tensions when governing climate change., Svenska Forskningsrådet Formas http://dx.doi.org/10.13039/501100001862, Deutsche Forschungsgemeinschaft (DFG)

Global Water Models (GWMs), which include Global Hydrological, Land Surface, and Dynamic Global Vegetation Models, present valuable tools for quantifying climate change impacts on hydrological processes in the data scarce high latitudes. Here we performed a systematic model performance evaluation in six major Pan-Arctic watersheds for different hydrological indicators (monthly and seasonal discharge, extremes, trends (or lack of), and snow water equivalent (SWE)) via a novel Aggregated Performance Index (API) that is based on commonly used statistical evaluation metrics. The machine learning Boruta feature selection algorithm was used to evaluate the explanatory power of the API attributes. Our results show that the majority of the nine GWMs included in the study exhibit considerable difficulties in realistically representing Pan-Arctic hydrological processes. Average APIdischarge (monthly and seasonal discharge) over nine GWMs is > 50% only in the Kolyma basin (55%), as low as 30% in the Yukon basin and averaged over all watersheds APIdischarge is 43%. WATERGAP2 and MATSIRO present the highest (APIdischarge > 55%) while ORCHIDEE and JULES-W1 the lowest (APIdischarge ≤ 25%) performing GWMs over all watersheds. For the high and low flows, average APIextreme is 35% and 26%, respectively, and over six GWMs APISWE is 57%. The Boruta algorithm suggests that using different observation-based climate data sets does not influence the total score of the APIs in all watersheds. Ultimately, only satisfactory to good performing GWMs that effectively represent cold-region hydrological processes (including snow-related processes, permafrost) should be included in multi-model climate change impact assessments in Pan-Arctic watersheds., Bundesministerium für Bildung und Forschung http://dx.doi.org/10.13039/501100002347

After nearly half century of planning, the construction of the controversial south-to-north water transfer1 (SNWT nan shui bei tiao) project in China was officially launched just before the end of 2002. China is one of the countries in the world that currently has severe problems relating to the management and utilization of water resources. In order to cope this circumstances, the idea of transferring water from the Yangze River to north China, the so called south-to-north water transfer1 project, was first conceived in the early 1950's by then leader Chairman Mao. This paper looks into taking the state of water shortage into consideration and economizes in water consumption by the citizens of Beijin China. Data were gathered form 300 citizens in Beijin by the questionnaires. It was found from the result that there were exist of economize in water consumption of action and awareness. However after accomplishment of SNWT, a lot of people express their anxiety about water shortage. With the implementation of the project, the government is caught in a dilemma of keeping water prices low to substantiate the economic needs and improving water use efficiency to honor the environmental objective of the project.

This paper reports on environmental survey in the Lantang Valley. It is called one of the most beautiful valleys in the world. Also, the water quality of Everest Highway and the Inner Shrine of Annapuruna Sanctuary was discussed in this paper. The electric conductivity indicated that Inner Shrine was the worst (835-94μS/cm). Lantang was mediocre (190-7μS/cm), and Everest was the cleanest (40-11μS/cm).

The rain water utilization equipment of the type which removed initial precipitation was developed low-cost in order to store the good rain water. And, the effect of this equipment was evaluated. The results are as follows. 1. The first tank stored the precipitation initial stage 3mm precipitation. And, the secondary tank stored the precipitation after 4mm. In comparison with the water quality of two tanks, component concentration of the secondary tank water variously decreased further than it of the first tank in about 1/3. 2. The water quality of the precipitation collected from the roof greatly receives the effect of roof material. it increased at about 10 times at the Ca2+ concentration. 3. The increase of the Ca2+ concentration is made to increase the pH value by the counteraction. pH of the water collected from the roof of the slate material shows the value in the latter half on the order of pH6 which is almost approximate to the neutrality.

ネパールの地形は、南部の標高150m以下のテライ、150～300mのシワリク、300～2,500mのヒル/ミドルマウンテン、2,500m以上のハイマウンテン等の高度帯に大別され、地質構造にも大きな特徴が見られる。そこで2007年8月から9月に、標高3,000m以下のこれらの地帯を代表する4つの地域(1)を選定し、飲料水の水質調査を実施し、その概要を把握した。また、ヒ素汚染が報告されるテライ(Parasi)においては、地下水のヒ素汚染の実態について調査した。 (1)飲料水水質調査地点 ハイマウンテン:Lukla(2,840m),Jomsom(2,710) ヒル/ミドルマウンテン:Kathmandu(1,300m),Pokhara(820m),Manakamana(1,300m) シワリク:Bharatpur(190m)テライ:Parasi(110m),Lumbini(100m)(2)ヒ素汚染調査地域 テライ:Parasi(110m)その結果得られた知見は,次の通りである。(1)ハイマウンテンのLuklaではpH6台後半の値を示すが、同じハイマウンテンのJomsomではpH8を示す。これは、地層の違いによるものと考えられる。(2)KathmanduだけがNH_4+を高濃度で検出した。これは、河川の人為的汚濁が原因であると考えられる。(3)タライの沖積地帯に位置するParasi、Lunbiniでは、他地域と比較して、Mg2^+、Ca^が高濃度に検出される。(4)Jomsomは、Pokharaの上流に位置し、上流には海成堆積層が存在する。水源が共通しているため、ともにCa^が80%近くを占める。(5)同じ高度帯に隣接するManakamanaとKathmanduは、地質構造が類似しているため、Na^+(30%超)、Ca^(40%前後)の比率が類似する。(6)ParasiとBharatpurは、各種成分濃度に関しては,後者が前者の約1/4と大きな違いはあるが、各種成分の濃度比は非常に類似している。(7)Parasi、Lunbiniの全硬度は、日本の水道水基準値(300mg/L)に近い値を示す。(8)ParasiのAsとBは、高い相関(r=O.97)を示す。(9)Parasiにおいては,ヒ素の高濃度値が局所的に分布する。(10)高濃度ヒ素の局所的分布の原因としては、地下の帯水層の深さ・地質(粘土・砂・礫)構造などが複雑に入り組んでいるためと推測される。タライ沖積低地に位置するParasiでは地下水のヒ素汚染が不規則に分布することを確認した。その分析には、帯水層の地質状況の調査が重要である。特に造山運動による摺曲や衝上断層による間接的な影響や地下に存在する蛇行跡などが帯水層のメカニズムを複雑化している。さらに、ヒ素の地下水への溶出と帯水層中の移動に関して、ヒ素の広域汚染源、ヒ素含有岩石・砕屑物、海成堆積物、河川と風化の影響、地下水中の化学物質(特に鉄化合物や硫化物など)、pH、酸化還元電位なども大きく関与すると考えられる。

On July 16, 2007, an earthquake of magnitude 6.8 was generated in Niigata Chuetsu district (called the Niigata Chuetsu-oki Earthquake). This report arranged information provided after a field work in Kashiwazaki of July 21 and an earthquake. In Kashiwazaki, I was able to check the disaster situation such as the collapse of the house or the crack of the road. At the stricken area, much support activity by a volunteer or the Japan Self-Defense Forces was performed. There was much damage in a certain town (Nishimotomachi and Higashihoncho) on a dune, and the damage of a Shinto shrine and the temple was outstanding. The place where the damage was big by this earthquake is the land where there is a dune on alluvial plain. In addition, the damage was related to a geological feature, the topography and the structure of the house.

Geographical survey institute carried out the study on the application of GIS for seismic hazard management and the research on the use of GIS in local government. The Great Hanshin-Awaji earthquake revealed the potentiality of earthquakes in urban and suggested the necessity of development and employment of Geographic Information System for urban earthquake disaster mitigation and restoration. While considerable numbers of studies on the earthquake have been undertaken, majority of research centers the examination of visualized output of damage and possible factors, such as land condition, a residential area and a street structure. This paper attempts to investigate the relationship between damage of area and possible factors including historical land use and geographical structure by using GIS. A continuous examination of the mechanism of decreasing disaster risk would be especially important.

Kyoto Kamogawa-river has historical heritage and landscape. However, on the other hand on an earlier occasion it was suffered from food disaster. The social concern with environmental and prevention for disasters of riverside area has been growing for the last several years. This paper discusses the issues related to the characteristic of hydrology and a measure of flood disaster in Komogawa-River Kyoto. From the hydrological data of Kamogawa-river were observed that it has not fluctuations of water level. Since 1935 this drainage basin was not suffered from flood disaster, in recent years hazard map and website information was provided by local government. Water quality of Kamogawa-river maintains good level from 1960; it was worried about water pollution by building of an industrial waste disposal facility. For the reasons mentioned above, it is an important point of the river management that from a point of view to environmental-prevention for disasters and an upper-lower district.

These papers are the result of a 1997-1999 group research project on the vicinity of Sanrizuka, Narita City. Our target area was the land that is now the Tokyo International Airport in Narita. The motivation for this project comes from the fact that this airport is situated near the Keiai University Sakura Campus. The aim of our research is to understand the historical circumstances of the settlements in this area dating from Meiji Era to the present day including the movement of settlers to and from this land due both to adverse conditions and to construction of the airport. We look at the problem of relocating people, the changes that took place over time, international comparisons, and the effect of these changes of the local culture. The surrounding areas of Sanrizuka changed from pasture land in the Edo period to goryo bokujyo, or designated pasture land for the Imperial Family after the Meiji Restoration. Following this, this land became a candidate site for the settlement of ex-samurai warrior families and finally for people in difficulties after World War II. The latter group included people suffering war damages, repatriates, Okinawans, as well as local people suffering from food shortages who were looking for land to cultivate and settle. This area developed into farming villages over a period of several decades. After repeated difficulties, people were finally able to settle, cultivate their land, secure foodstuffs and attain stability in their daily lives. It was at this point that the government decided to target their land for the construction of an international airport. The settlers had no choice but to move out in the end. With these points in mind, we visited public and private organizations for historical materials and artifacts and heard firsthand from several settlers, their children and relatives regarding their predecessors' settlement and lives in the beginning of the Meiji Era and after World War II. Three research papers on the subject have been produced previously. "Empirical Research on Social and Cultural Characteristics in the Surrounding Areas of Sanrizuka, Narita City, Chiba Prefecture" by Yoko MURAKAWA (Journal of Environmental Studies NO.6 and NO.7), and "Settlements in Narita City and its Outskerts : Army 'reconnaissance records'" by Fuhito KANDA (Journal of Environmental Studies NO.7). We have since produced two additional reports on the result of our research which was concluded in 1999. One of these is the report titled" "A History of the Boso Peninsula and the Opening up the Shimousa Plateau : A Comparative View with the Clearing of the Mekong Delta (Part One)" by Yoko TAKADA. The other is the "Reclamation of Sanrizuaka after the War by settlers from Kumejima, Okinawa" by Fuhito KANDA and Yoshiko TAKAZAWA. Ms.Y.MURAKAWA, currently in the United States, will be reporting on this theme during the next academic year.

Reconaissance survey was carried out to investigate hydrologic characteristics of flood flow events occur-ring in the upper basin of Ohno river, Oita prefecture. The studied area had suffered devastating floods on three different occasions since 1983,in July, 1983,July 2,1990 and September 3,1993. Until then, the studied area had not experienced any serious damage by floods for nearly 90 years. Before 1983,the oldest record of flood damage dates back as far as 1870. These three flood events were caused by storm rainfall due to Bai-u or typhoon. Heavy rainfall attaining more than 50 millimeters per hour caused flood flows in the upper basin of Ohno river. As a result, in the urban area of Taketa city, many houses were innundated and railroad bridges and road bridges were destroyed or washed away. Among these three floods, the first and third ones were due to Bai-u or frontal rainfall and second one was due to typhoon #9313. Unexpectedly, the flood events did not always result in disaster. For example, there was heavier rainfall on August 26th, 1982,(430.0 millimeters per day), the studied area had no serious damage from this heavy rainfall. This might be explained by the distribution of hourly precipitation and amounts of effective rainfall. The details of hydrogeomorphic characteristics of the drainage basin were already described in the previous paper, which readers may refer to concerning these data. The annual change of precipitation and runoff at Miyado and Namino stations are shown in Fig. 2. The maximum ratio of runoff rate was 75.55% of 1980 and minimum rate was 47.4% of 1985. Judging From Fig. 2 there is a increasing tendency for annual precipitation. As has already been pointed out by Kayane and Takeuchi (1971) that the runoff ratio exceeding 80% is doubtful and annual evapotranspiration is fairly constant, say, 800millimeters in the upper basin of Ohno river. Fig. 3 shows the monthly change of precipitation and runoff height. Although seasonal change can clearly be recognized, there is a slight lag between change of precipitation and that of runoff height. The streamflow discharge of Ohno river decreases downstream from Inukai to Shiratakibashi. This phenomenon can be explained by influent seepage to the alluvium of the downstream area. If we denote probability density function as f(x), then exceeding probability of W(x) is expressed as follows ; [numerical formula]Return period T is defined as [numerical formula]where n is the number of years, in this case 24 years. Twenty-four consecutive years (1974-1997) of daily rainfall and runoff data lead to a total of some 17520 input-output pairs for the drainage basin. A Hazen plot of daily maximum rainfall of each year on probability paper is as shown in Fig. 5. From the regression line of this figure the maximum daily precipitation of 400 millimeters will occur only once in 100 years, that is, a return period of 400mm per day could be 100 years and 99% of daily precipitation will not exceed this value.

This study is one part of a cooperative study entitled "Empirical Research on the Social and Cultural Charactaristics of the surrounding areas of Sanrizuka, Narita-city, Chiba-prefecture." The writer focuses on the historical changes in the Boso peninsula of Chiba Prefecture brought by the reclamation policy of the Meiji Government that was carried on in Shimousa. This was a designed for unemployed samurais and the destitute of Tokyo to clear woodlands on the Simousa Plateau. The names of the hamlets that were founded by settlers still remain in north western Shimousa. The purpose of this study is to examine more closely the long-term historical development of the origins of settlement in the Sanrizuka area located in Shimousa after World War II. The writer will compare the process of the opening up of the Shimousa Plateau with the clearing of the Mekong Delta in the next issue.

国際野生生物の取引(貿易)における日本の活動は,20世紀の間,地理的に小規模ながら,その高い人口密度と急速な経済成長の理由から,重要となっています。日本は,世界の中でも一人あたりの野生生物の消費が最も高い割合をしめています。この書類では,虎,鯨,象に関する日本の取引に焦点を合わせ,これらの種が,野生生物の取引の上で政治及び経済にいかに関わっているかを説明していきます。

Environmental problems are a distortion - much like the conditions of a cold -arising from our pursuit of economic growth by exploiting nature. In spite of our efforts to resolve individual problems respectively, we cannot hope for effective result. It is essential that we solve fundamental problems through a system of international cooperation. Most importantly, we must eliminate the disparity between north and south, in which "well fed advanced countries" and "starving developing countries" simultaneously exist. These circumstances force developing countries with neither technology nor manufacturing bases to live piecemeal by their resources, such as their forests. One solution is to introduce fluidity into the mix of disparity. By emigration from poorer countries to richer ones, people can earn valuable foreign currency, and if they transfer their acquired skills to their native country, this will be helpful in reducing the gap. In this day when environmental issues of a global scale confront us, gaining profit exclusive to a single country is no longer a viable way of thinking. Accordingly, our most pressing concern as we move towards the 21^ century is to build a society in which people of other nationalities can live comfortably. In other words, a society of multicultural coexistence. Of course, coming into contact with things unfamiliar causes friction. By persistence and continuous exposure, however, we are able to reach an understanding of one another. Changes in one's personal development may accompany this process. We see that by their presence in this country, international residents are indeed moving Japanese society in a positive direction.

この論文は,戦後千葉県各地で入植・開拓が行われ開拓農業協同組合が全県下で113ケ所も組織されたが,それらを総体として取り上げるのではない。三里塚の御料牧場に入植した沖縄県出身者の入植時の非常なる苦労やその組合の推移を辿り,かつその中心となった久米島出身者との関係を追跡したものである。沖縄県人は伝統的に海外や日本本土への移民が多かったが,久米島もその例外ではなかった。その一人に与世盛智郎のようにハワイで薬剤師として活躍していた人材も存在した。その与世盛が戦争最末期以後,日本本土に在住していたので,郷里に帰れなくなった県人とくに久米島出身者を集めて御料牧場の開放に着手し,開放に成功した。与世盛が組合を去った後,組合の経営は娘婿の上江洲智泰ら同じ久米島出身者に委ねられ,ようやく生活の安定が得られたとき,全く突如として成田空港問題が発生し,立ち退きを余儀なくされたのである。この論文は全体の構成を打ち合わせた上で主として神田がまとめたが,その際,数回の聞き取り調査については高澤の協力を得た。とくに沖縄本島での石川友紀・上江洲智泰氏との,久米島での喜久永正・上江洲智隆氏との面談については細部にわたる点検を経て作成されたものである。, After World War II, settlement and cultivation throughout Chiba Prefecture increased rapidly. Agricultural Cooperative Societies for land reclamation were organized in quick succession and soon numbered 113. This paper investigates the changes affecting agricultural society organized by Okinawans, who settled in Sanrizuka, Chiba Prefecture after World War II . Traditionally Okinawans emigrated both abroad and to mainland Japan in large number. People in Kumejima were no exception. One was Chiro YOSEMORI who was a pharmacist in Hawaii prior to the war. He was in mainland Japan at the last stage of the war and began, and continued, the movement for the release of goryo bokujyo, or pasture land belonging to the Imperial Family, to general citizens, including Okinawans. Yosemori gathered together Okinawans, who could not return to Okinawa, and helped them settle in the former goryo bokujyo in Sanrizuka. Most of these people were from the island of Kumejima and they became the central activists of this settlement and movement for land reclamation. This paper looks at the hardships they experienced up until and during the resettlement of this area. After Yosemori, the management of the society was left to Chitai UEZU, Yosemori's son-in-law, and other people from Kumejima. When, at last, the settlers had secured their livelihood and attained a fair level of stability in their daily lives, the government decided to build an airport on their land they were forced to move. This paper was mainly written by KANDA after formulating and working over the whole plot with TAKAZAWA, who cooperated in making the close inspection on the interviews with Professor Tomonori ISHIKAWA at Ryukyu University, Mr. Chitai UEZU, in Mainland Okinawa, and Mr. Tadashi KIKUNAGA and Mr. Chiryu UEZU in Kumejima.

Environmental problems have signaled an urgent need for corresponding plans for problems of the human-race. In a society affained by high economic growth, in which there is a great deal of consumption and disposal, people tend to place an emphasis on surface values such as the pursuit of profit, convenience and comfort. In this climate it is easy to become distracted from crucial matters of the environment and social charge. What is needed is to establish "a society sensitive to environment problems" adopted at the Earth summit. For this purpose it is necessary to enact punitive laws in order to protect the environment. However, there are limits these laws can have in gaining the deslred effect. In this paper the illegal disposal of cars is considered as a means of redefining the categories of crime Cars are disposed of illegally essentially because convenient locations for this purpose exist. In an investigation of environ mental criminology, Cohen and Felson note that these acts are most likely to occor when 1) there is a clear motive 2) no one is around to observe the act 3) the location is known to the criminal. Brantingham also mentions that the location is most often an area freguented by the perpetrator. Carter and Leech confirm this and add that the location is one the prepetrator feels is most convenient or desirable for the act. In light of these findings, ways of perventing envioron mental crimes are considerd for the cities of Sakura, Tokyo, Osaka, Kyoto, Yokohama and Yokosuka and others.

Using the internet, newspaper articles concerning environmental problems during the past 12 years were found. The number of articles was then compared to the latest trend of standing dead trees in order to determine the year on year correlation. The results are summarized as follows : The number of articles concerning environmental problems and the air pollution remarkably increased during the period of the 1988～1992. The number concerning these two matters increased again in 1997 and 1998,though the number of articles decreased for 1993～1996. The number of articles concerning acid rain showed a similar tendency, but decreased in 1998. On global warming, the number of articles greatly increased in 1997 and 1998. By contrast, the number of articles concerning the disruption of the ozone layer decreased, although this problem became much worse. In 1992,however, it peaked in number. This same tendency also appeared in the change of consciousness in students. On the other hand, the problem of the disruption of forests in which they are very interested is not often covered in newspaper article. The continual information concluded what the present situation is, not temporary one, is desired. As for standing dead trees, there seem to be many causes according to place, different kind of tree and so on. The effect of acid rain has also been considered. In Nikko, areas in which there are standing dead trees reached 2500ha in 1996 and is extending into Nikko and Tanzawa. Investigations into the causes and ways to protect trees are now under way. Recently, research into the effects of acid rain on trees has increased.

Since the introduction of quantitative analysis of stream morphology by Horton, (1945), considerable efforts have been devoted to the study of drainage networks, and ordering systems have been proposed to give a better quantitative description of natural stream networks. Three statistical laws, the law of stream numbers, the law of stream lengths and the law of stream slopes were proposed by Horton. These three laws have been widely tested and accepted. The so-called "Horton analysis" has become a standard procedure for reporting the structural properties of channel networks although Horton's original ordering scheme has now been generally superseded by Strahler's modification. A significant number of relationships have been posed to describe the complex fashion in which hydraulic, hydrologic and geomorphic variables interact in channel networks. As yet, stream number data on the networks of seventh order have seldom been used to test and compare the accuracy of the Horton model. One of the purposes of this investigation is to examine the properties of channel networks. The results of the network analysis of the studied basin showed a good agreement with Horton's law. Secondly, the prevailing direction of stream courses of each order were examined and although there were no definite tendencies, the stream courses of each order show some dominant distributions in the ENE-WSW direction.

The purpose of this article is to explain two points. 1) How Yahagi, which was one of Sakura 7-Maki and a horse pasture in Edo Era, became Toyomi Settlement located in Toyoma village (present Narita city), Kuga village (present Tako town) and Osuga village (present Taiei town) in the early Meiji Era. 2) How these were settlements in "reconnaissance records" of the Army's General Staff Office.

In order to clarify the regional characteristics of acid rain in Chiba Prefecture, the data from precipitation obtained. during the period from April 1997 to March 1998 with the aid of environmental monitoring volunteers of the Institute of Environmental Studies of Keiai University have been analyzed. The results of the analyses are summarized as follows : 1) In the pH mean value distribution diagram in the warm period in fiscal 1997,the value of pH5.0 or less was distributed near Sakura. And, the value of pH5.0 or less was distributed near Sakura and Choshi in pH mean value distribution diagram in the cooling season. 2) The value over 0.7 which is high in the west in both the warm period and the cooling season is distributed on NO_3^-/nss-SO_4^ ratio (N/S ratio) of the Northern Region in Chiba Prefecture. There is otherwise a region over N/S ratio of 0.7 in the Pacific coast in the cooling season. In the meantime, the low value appeared in the region which was close to the Keiyo industrial area and Kashima maritime industrial district. 3) The pH distribution and fractional acidity ([H^+])/([nss-SO_4^]+[NO_3^-]) distribution in the warm period show a very good correlation. The relationship between pH and fractional acidity (A) in the warm period is shown in the following equation. pH=-2.42A+5.65 r=-0.87 And, the relationship between pH and fractional acidity (A) in the cooling season is shown in the following equation. pH=-2.07A+5.85 r=-0.84 4) In the neutralization of the acid of the Northern Region in Chiba Prefecture, NH_4^+ also greatly contributes more to the nss-Ca^ approach 2～7 times. In the warm period, the degree is bigger in the east than in the west. It is an inland in the cooling season, and is large.

Chiba Prefecture is composed of parts belonged to the Kanto Plain and of a main part of the Boso Peninsula, which faces to the Pacific Ocean. It is located just under the strongest subtropical westerly jet stream of the troposphere. So, the NW-NNW winds prevail in the northern part of the Prefecture in winter and SW-WSW winds in the southern part, which bring oceanic climate. In this paper, first, classification of climate landscape caused by the wind conditions was presented. They are : wind-prevention hedges, wind-prevention nets, windbreaks surrounding houses, damages of plants and vegetation by salty wind, wind-shaped trees, sand dunes, wind prevention by sasa/bamboo shoots, fixing method of roof tiles, and weak-wind landscape. Secondly, next steps of the studies on this subject were discussed. (i) To make clear the effects of the prevailing winds on the landscape quantitatively. For example, are they the winds associated with winter monsoon, summer monsoon, wind by typhoon or valley/mountain winds etc.? (ii) Chiba Prefecture has been divided climatologically by wind conditions. It is therefore needed to make clear "how are the regional distributions of the wind-landscapes corresponded to the wind regions?"

Ethnographic and ethnoarchaeological studies at a number of pottery-making villages were conducted at various parts of the Philippines. As archaeological excavations at a pottery making center were rarely conducted in the Philippines, this work is important in order to clarify their history and different activities involved in producing potteries. The problems to be addressed will be archaeological. This is a report of the archaeological test excavation of a pottery making village in the middle reaches of the Cagayan River, i.e. to be specific in Atulu, Iguig, Cagayan. The research was conducted by Kazuhiko Tanaka and a team from the National Museum headed by Ms. Amalia de la Torre. One 1×1m square was set up on the top of a hill where the village was located. The excavation reached the depth of 80cm from the surface. The location to excavate was chosen because the landowner, who dug up a post hole while construction of his house was done, found a glass bottle and a blue and white bowl. The glass bottle and a blue and white bowl were probably dated to the latter half of the 18th century or later. But, no similar nor related artifacts were found during this test excavation. The excavation revealed the following : (1) The deposit was composed of three layers. Layers I and II contained artifacts. But Layer III was sterile. (2) Earthenware sherds were uncovered from Layers I and II but the colors of the pastes of main sherds were different. The characteristics of the earthenware sherds from Layer I was similar to those of much contemporary pottery (the pottery presently produced). The sherds from Layer II are different from those found in Layer I. (3) The presence of stones and the weathered conditions of artifacts in Layer II showed actions and/or effects of the river. Further research will be needed, since this was only a test excavation. What will be recommended is to have an extensive research to be able to map the activity areas of a pottery making village and to understand more freely the horizontal stratigraphy of the place.

In order make clear the relation between airborne pollen counts of Cryptomeria Japonica and Cupressaceae and meteorological conditions in the Metropolitan area, the Airborne pollen is surveyed at three pollen count stations (Suginami, Satte and Akiruno) from February to April 1997. The results are summarized as follows : 1) In Suginami and Satte, the dates of beginning of dispersion were February 8 and February 16 respectively. In Suginami, Satte and Akiruno, the maximum pollen counts were taken on April 8 (265/cm^2), March 7 (182/cm^2) and April 9 (1036/cm^2) respectively. And in those stations the total pollen counts were 1933/cm^2 (Suginami), 1862/cm^2 (Satte) and 10752/cm^2 (Akiruno) during the period of February 28-April 30 respectively. 2) The peaks of the pollen counts on the daily variation of these agree with the peaks of the daily maximum temperature at all three stations March 7 and April 8-9,3) The coefficient of correlation between the pollen counts and the daily maximum temperature show the high values in the period of increasing pollen dispersion in three stations (Suginami : 0.75,, Satte : 0.56,Akiruno : 0.79). But the coefficients show the low values after the period in three stations. 4) The main origin of pollen in Suginami and Akiruno is probably an artificial forest of Cryptomeria Japonica and Cupressaceae in the western Kantou, and that in Satte is probably an artificial forest of Cryptomeria Japonica and Cupressaceae in the northern Kantou, judging from wind direction and pollen counts. 5) These results suggest the airborne pollen counts are not affected only by the meteorological conditions, but also by the biological conditions of the plants.

The catch in the seas near Honshu, the main island of Japan, fluctuates significantly in accordance with the occurrence of ENSO events. This is not clear in the open seas. It is considered that the catch depends closely upon the conditions of the Kuroshio currents near Japan. An example is given by the Pacific saurel and mackerel in Chiba Prefecture on the Pacific side of Honshu, Japan. In most El Nino years, the catch decreased, but more significantly is the increase in the next years of the El Nino event. The average of saurel caught increased in the five cases after an El Nino year to the next year was 14,700 ton and that of mackerel was 18,600 ton. Such phenomena seem to be caused by the negative effect for the catch in the El Nino years, which resulted in the change of spawn regions in the seas under the influence of the Kuroshio current affected by the El Nino event. It was also shown that sardine catch decreased sharply in the El Nino years and recovered in the next years. In the La Nina years, the tendencies were reversed. These tendencies, however, were different between the periods of low level (total catch less than 800,000 ton) and high level in the long-term cycles of sardine catch for example.

In order to investigate the quality of city water in Chiba Prefecture, the data of the water quality were collected in June 1996 and June 1997 with aid of the students of Chiba Keiai Junior College, Keiai University and Chiba University. The data are analyzed to make clear the regional characteristics of the city water in terms of the water quality. The results of the analyses are summarized as follows : 1) The electric conductivity, pH, the concentrations of dissolved ions and others of the city water depend on the location of source of the water. 2) The concentration of the constituents of the city water in the area around Inba Lake, are less than those of other areas. The reason for this is that the source of water of this area is located on more upstream portion of Tone River than that of other areas. 3) On the other hand, city water in the ocean-side Kujukuri area contains a high concentrate of these constituents. 4) From these fact, it is considered that the high concentration of these constituents in city water is considerably influenced by sea water.

In studies of suicide, a common problem is an over-focus on psychopathology of individual suicidal acts. As a result, the social determinants of suicide are often obscured. In order to rectify this situation, in this paper, we took a Durkheimian approach and focused on social factors that may be linked to suicide. We reviewed research on suicide in Okinawa from an international perspective and reconsidered suicide as a socio-cultural phenomenon. We also compared suicide in Okinawa to trends in mainland Japan. Okinawa prefecture has a unique socio-cultural status in Japan including the experience of having been occupied by the USA from the end of World War II until reversion to Japan in 1972. The suicide rates among males and females aged 10-19 during 1970-83 were at a relatively high level and this change was quite different from that of other areas in Japan after World War II. It was suggested that these rates were affected by reversion anxiety (social anxiety associated with the reversion of Okinawa to Japan). High rates among young and middleaged adult men were suggested to be related to both acute and chronic anomie. For elderly women their low suicide rates may be linked to their high morale and religious roles based in traditional culture as well as to their large social networks. It was suggested that these are possible fruitful areas for future research.

The meaning of "preventive diplomacy" has been used widely in the field of United Nations peacekeeping. This paper aims at clarifying the meaning of "preventive diplomacy" on the following five parts. 1) The meaning of "preventive diplomacy" in the United Nations has been changing historically. The Charter of the United Nations prescribed the preventive measure as one of the compulsive measures in chapter 7 of the Charter. But the meaning of "preventive" has been changing. It has meant variously according to the Secretary General Hammarskjold, de Cuellar, Boutros-Gahli and so on. In the age of de Cuellar, ., for example, preventive diplomacy meant one of the measures of peaceful settlement of international conflict as in chapter 6 of the Charter. 2) As the definition of "preventive diplomacy" is examined. "Preventive diplomacy" should be distinguished, from preventive measure" and "preventive action". There are many actors in "preventive diplomacy", such as ethnic groups, non-governmental organizations and so on. Preventive diplomacy prevents not only international conflicts but also domestic conflicts. There are many definite measures of "preventive diplomacy" such as fact-finding, enquiry, global-watch, inspection, monitoring, early-warning, mediation, conciliation, confidence-building and so on. 3) An early-warning system in the United Nations is the most important measure of "preventive diplomacy". There are many actors in an early-warning system, including various types of the collectors of information, various types of senders of information and various types of receivers. Therefore it should not be necessary to collect information to the Secretariat of the United Nations. The Secretariat should co-ordinate various actors in this early-warning system. 4) Mainly there are three problems to pursuing "preventive diplomacy". Firstly, it is very difficult to verify steps in the process of "preventive diplomacy". Secondly, when we pursue "preventive diplomacy", national sovereignty is a barrier. Thirdly, there is no rules on "preventive diplomacy" in the Charter of the United Nations. 5) The concept of "preventive diplomacy" fundamentaly suggests the five visions for the conflict resolution system. (a) We must consider the conflict resolution system not only in the states system but also within the system of transnational actors. (b) Not only after the outbreak of conflict, but even before, the resolution of the conflict should be examined. (c) The principle of non-intervention in the domestic matters may be challenged. (d) The prescriptions for non-state actors such as non-governmental organizations, ethnic groups and individuals may be required in the Charter of the United Nations. (e) An early-warning system will lead for an integrated and comprehensive approach for the functions and operations of the United Nations.

Weather descriptions in two dairies, "genba nikki" in choshi and "yoshino Families Diary" in nagareyama were investigated. Followings are pointed out : 1. Long tarm tendency of rainy days in choshi shows similar pattern to that of yokohama and kofu. 2. Weather description in genba nikki seems to be simple and in some cases, it disregars weak rains as compared with that of yoshino families, diary. 3. Descriptions of yoshino's contains important records such as seasonal phenomena. But it contains occasionally some unbelievable phenomena during the respective season.

In order to make clear the relation between airborne pollen counts of Cryptomeria japonica and Cupressaceae and meteorological conditions in the Metropolitan area, the airborne pollen is surveyed at three pollen count stations (Sakura, Suginami and Satte) from February to April 1995,and at four stations (Sakura, Suginami, Satte and Akiruno) from February to April 1996. The results are summarized as follows : 1) The peaks of the airborn pollen counts agree with the daily maximum temperature at three stations on March 11th and April 1st, 1995. 2) The peaks of the pollen counts on the daily variation of these agree with the peaks of the daily maximum temperature at four stations March 11th and 16th, 1996. The maximum pollen counts are observed on the four stations on March 16th, 1996. 3) The total pollen counts at the stations of Sakura and Suginami are about 9000/cm^2 in 1995. These counts in 1995 were 15 times as large as those in 1996. As compared with the total pollen counts of Sakura, Suginami and Satte, that of Akiruno is more than 4 times of those in 1996. 4) The coefficient of correlation between three days mean value of pollen counts and the deviation of daily maximum temperature, which is defined as the difference between the mean value of daily maximum temperature of 28 days before a fit day and that of 2 days (the fit day and the day before), are about 0.47-0.48 in three stations in 1995. In 1996,the coefficients show approximately the same values as those of 1995 in Satte and Akiruno stations, but those of Sakura (0.72) and Suginami(0.78) are larger than that of 1995. 5) The airborn pollen counts increase in the case of the wind direction with high frequency. 6) The more the wind blows strongly, the more the pollen counts increase.

In order to make clear the regional characteristics of acid rain in Chiba Prefecture, the data of rainfall which were obtained during the period from April 1995 to March 1996 by the environmental monitoring volunteers of the Institute of Environmental Studies of Keiai University have been analyzed. The results of the analyses are summarized as follows : 1) The mean pH values of rain samples collected at every rain in the northern part of Chiba Prefecture are lower than the values of the area surrounding this part in both the warm and the cool seasons. 2) The mean values of NO_3^-/nss-SO_4^ concentration ratio (N/S ratio) in the cool season are higher than the values in the warm season. 3) In the areas where the N/S ratio higher than 1.0 appeared with high frequency, the high concentrations of the ions are observed. 4) The pH value shows high negative correlation with fractional acidity ([H^+]/([nss-SO_4^]+[NO_3^-]) in both the warm and the cool seasons.

The survey of the water quality of wells was carried out in Hoa Thuan village in Me Kong Delta of Viet Nam, August 1996. The village is situated beside the mouth of the Me Kong River. The wells are on the sand ridge which extends from north to south. The results are summarized as follows : 1) The electric conductivity, the concentrations of NH_3-N, Fe and Cl^-, the hardness and so on of the water of the deep wells are higher those of shallow wells. Those values of the deep wells on the sand ridge decrease as the well stands apart from the other toward the south. This is considered to occure from increase of the distance between the sand ridge and Co Chien River. 2) The value of NH3-N in the deep well is higher than that of shallow well, and this is caused by the organic matter which is accumulated in the deep layer. 3) Excepting the well in the northern part which have water like sea water with respect to the salinity, the shallow wells have water exhibiting the low level salinity. 4) The deep wells are classified into three groups according to the water quality, that is, the well highly contaminated (located on the north end of the ridge to about 4 km point toward the south), medially contaminated (located to about 7km point) and low contaminated (located to about 10km point).