論文

本研究は，剪定枝葉を使用したチップマルチング材が植栽樹木に及ぼす影響を検証し，チップの公園内利用を促進することを目的とした。対象地は、国営明石海峡公園淡路地区とし，カワズザクラ(Cerasus×Kanzakura ｀Kawazu-zakura´) にチップマルチングを施用することによる土壌環境の変化が植栽樹木に及ぼす影響を調査した。その結果，チップマルチングによって地温上昇の抑制効果，地温変動緩和効果，土壌水分の保持効果が確認され，それらの効果がSPAD値を高い値で維持し，夏期の最大光合成速度の低下を回避させる結果となった。チップマルチングが植物の生理活性を維持させることが示唆され，公園内での剪定枝葉の利用促進に繋がり得る可能性が示された。

Water quality and fluctiation pattern in water level of 38 small irrigation ponds were investigated in Hokudan- cho, Hyogo Prefecture, West Japan. Temperature, water temperature, pH, electric conductivity (EC), dissolved oxygen (DO), N02-, N03- NH4+, SiO2, PO43-, chemical oxygen demand (COD) and water level were surveyed in each pond from May 2002 to April 2003. The result showed that there was not so much difference in water condition of among ponds, because water is frequently pumped from a pond to another pond. The existence of water plants and polluted water from residences influenced water condition. The water level of most irrigation ponds fluctuated dramatically from spring to the end of summer.

I am researching the Aso region to clarify the multilayered area of the regional circular and ecological sphere and the method for its construction. The largest area is the basin of six class A rivers flowing down from the Aso region as a regional circular and ecological sphere. Approximately two million people live in this basin, and 2.3 million people in the Fukuoka metropolitan area also use its water resource. The population of the Aso area, which is the source of the water, is about 210,000, and it is estimated that the population will be reduced by half by 2050. In the Aso area, there are more than 20,000 hectares of semi-natural grasslands, which play a significant role as a groundwater recharge area. The area of the grasslands is decreasing year by year due to the aging of the people involved in maintaining and managing them, and it is predicted that more than half of the grasslands will be lost by 2050 compared to 2003. To halt the decline in grassland areas, it is necessary to reduce the amount of labor required for burning at the end of winter.

広域的に過疎化が進行する地域を事例として,地域再生の展開とその起点となった合意形成過程の展開に着目して,人口減少社会における地域経営の方法論に関する考察を試みる。研究対象として,地域づくり導入期に意識的に行政支援に依存しなかった地域が,明確な利益・経営規模の目標を掲げて農家民宿を計画して,合意形成の時間的制約を意識した結果,一部の構想賛同者のみで活動を起こした事例を取り上げる。具体的な研究課題として,対象地域が次第に地域の合意(協力)を拡大させると共に,行政による支援施策を呼び込みながら地域内の賛同者を拡大させ,活動を拡大させていった経緯を時系列的に読み解くことを目的とする。

I investigated birds from 15 January to 24 February 2004 along 8 wooded streets in central area of Osaka, Japan, in order to determine which environmental factors of wooded street are important as habitat of birds in winter. Eight species of 218 individuals were recorded at 2 times observation of the streets. I used a satellite image to identify the distribution of vegetation in my study area. The normalized difference vegetation index (NDVI) of each grid cell was calculated. The value of NDVI that indicated the threshold value for vegetation cover were 0.3 and more, based on the ground-truthing from December 2003 to February 2004. The proportion of vegetation cover within 50 m from a recording point was calculated in each bird species. The average vegetation cover proportion of Hypsipetes amaurotis and Sturnus cineraceus was more than 25 %, while that of Passer montanus was around 5 %. Almost all individuals of species except Passer montanus were significantly recorded in buffer areas within 100 m, 200 m, 300 m and 400 m from the edge of 2 ha and more woodlot.

1970年代にバイエルン州で初めて作製された生物空間地図は,その後ドイツの自然保護において,必要不可欠な資料として位置づけられ,ドイツ各地で作製されるようになった.地図作製手順には,当初から大きな変更がないものの,具体的な作業方法は大きな変化を遂げた.一般的だったカラー空中写真にかわり,最も重要な基礎資料として赤外カラー空中写真が利用されるようになった.地理情報システムの活用によって,情報はすべてデジタル化され,コンピュータ上で地図が作製されるようになった.本論では,最新の地図作製方法とその応用について紹介するとともに,我が国における生物空間地図を生かした生物多様性保全のあり方について検討した.