• 제목/요약/키워드: secondary forests

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Development of New Surfaces and Materials for Separation Science

  • Linford, Matthew R.
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2015년도 제49회 하계 정기학술대회 초록집
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    • pp.59.1-59.1
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    • 2015
  • In the Linford group at Brigham Young University we have recently developed three new sets of materials for three different areas of separations science: thin layer chromatography (TLC), high performance liquid chromatography (HPLC), and solid phase microextraction (SPME). First, via microfabrication we have grown patterned carbon nanotube (CNT) forests on planar substrates that we have infiltrated with inorganic materials such as silicon nitride. The coatings on the CNTs are conformal and typically deposited in a process like low pressure chemical vapor deposition. The resulting materials have high surface areas, are porous, and function as effective separation devices, where separations on our new TLC plates are typically significantly faster than on conventional devices. Second, we used the layer-by-layer (electrostatically driven) deposition of poly (allylamine) and nanodiamond onto carbonized poly (divinylbenzene) microspheres to create superficially porous particles for HPLC. Many interesting classes of molecules have been separated with these particles, including various cannabinoids, pesticides, tricyclic antidepressants, etc. Third, we have developed new materials for SPME by sputtering silicon onto cylindrical fiber substrates in a way that creates shadowing of the incoming flux so that materials with high porosity are obtained. These materials are currently outperforming their commercial counterparts. Throughout this work, the new materials we have made have been characterized by X-ray photoelectron spectroscopy, time-of-flight secondary ion mass spectrometry, scanning electron microscopy, transmission electron microscopy, etc.

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당지동의 산화적지의 초기식생천이 (The Early Vegetational Succession of he Burned Area in Dangji-Dong)

  • Kim, Woen;Jeong Ho Suh;Chong Un Ri
    • The Korean Journal of Ecology
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    • 제6권4호
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    • pp.237-242
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    • 1983
  • This is an investigation on the secondary vegetation and succession in the mixed forests destroyed by the severe crown fires on April 8, 1982. The results are summarized as follows: The floristic compositions in the investigated area are composed of 63 kinds of kinds of vascular plants. The biological type shows $ H-D_1, 4-R_5-e$, which is supposed to make a progress to the $ H-D_1-R_5-e$ type. Dominant species are Spodiopogon sibiricus (100.00)-Carex humilis var. nana (70.52)-Miscanthus sinensis var. purpurascens (61, 06)-Lespedeza maximowiczii (57.53). Lespedexa maximowiczii is prevailing as the dominant species in this area. The species diversity(H) and eveness index(e) show 3.00 and 0.74 respectively, so that the species are various and shows uniform distribution comparatively in these communities. Degree of succession(DS) is 479 in the investigated area, the value of which is comparatively higher than that of Chungcheongbuk-do area at the second year afer fires. After the crown and trunk of trees were scorched by the crown fires, the pine tree (Pinus densiflora) died and the other species could be survivd after sometimes. It some that Quercus serrata. Q. dentata, Maackia amurensis, Lespedez cyrtobotrya, Platycarya strobilacea and Lindera glauca are the fire-resistant plants.

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Production, Assessment and Marketing of Lichens for Economic Upliftment and Livelihood Generation of Rural Communities in Kumaun Himalaya

  • Pant, Girish Chandra
    • Journal of Forest and Environmental Science
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    • 제30권3호
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    • pp.267-276
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    • 2014
  • Collection of lichen together with tree twigs of oak and other trees bearing abundant growth of lichens is a common practice among the villagers and the rivals residing near Oak forests in Kumaun Himalaya. Nainital forest division represents about Twenty nine percent vegetation of the Oak forest in Kumaun Himalaya. In Kumaun, the lichen trade share is decreasing at an alarming rate of 21.93% which requires immediate actions by the Government. Lichen contributed significantly to household earnings with off-farm activities and this sector was found second highest income creator after Agriculture. It is a source of cash income during the season of extraction, which increases economic access to food. It has been observed in the present study that the secondary collector and transporters together get maximum share (>50%) of income generated from lichen, thus economic exploitation of the poorly educated people by the traders was still prevalent in the area. To improve the socio-economic standard of the people of Kumaun, it may is necessary to increase and improve the lichens resources of the area. There is a strong need for scientific management, best harvesting practices and strict monitoring of resources. The present study was conducted to assess the present and future resource potential for the conservation and sustainable management of lichens, existing market mechanism, role of Lichens in economic upliftment and livelihood generation of rural communities in Kumaun Himalaya.

한강유역(암사동, 대심리, 혼암리)의 석기출토지의 식물상 조사 (An Investigation of Flora on Archaelogical Districts of Han River Side, Amsadong, Daeshimli and Hunbaukol)

  • 이영노
    • Journal of Plant Biology
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    • 제15권s호
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    • pp.33-49
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    • 1972
  • Recently two thousand year old several villages ruins discovered at Amsadong, Daeshimli and Hunbaukol near the Han River side in Korea. An investigation of the present flora of these three localities was done. There are 84 families including 419 species of vascular plants. The vegetations of flora in the localities of the Han River side are very similar. the forests are poorly developed and appear as the secondary vegetations. The reforest plants can be recognized as Pinus rigida, quercus acutissima, Q. serrata, Robinia pseudoacacia and Alnus hirta. Herbaceous plants of Miscanthus sacchariflorus and Phragmitis japonicus bind up the soiles of the Han River side. Populus nigra grows abundantly in the moist places of sand bars which are located on the river side south of Daeshimli and on the northern side of the Han River across from Hunbaukol. These three area are fully cultivated but still many primitive farm techniques are employed. Farm produce crops include rice, corn, barley wheat, other vegetables, and a few ornamental plants. In this study the author found flower color variations ranging from a dark blue to a pale blue, and chromosome number differences existing between the populations of Commelina communis. The dark blue flowered taxa chromosome number is 44 and in the pale blue taxa it is 72. The wild white flowered Chrysanthemum is Chrysanthemum zawadskii Herb. ssp. acutilobum and which has finely lobed leaves, and has 54 chromosome in the root tip cells.

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인간간섭하의 수도권 그린벨트 내 식물군집의 동태 - 삼림군집의 구조와 이차천이 - (Dyamics of Plant Communities under Human Impact in the Green-Belt nearby Seoul -Structure of Forest Communities and Secondary Succession-)

  • Kim, Joon-Ho;Yoonsoon Kang;Lee, Sueng-Woo;Cho, Kang-Hyun;Kim, Yongtaek;Saheon Ha;Min, Byeung-Mee
    • The Korean Journal of Ecology
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    • 제12권4호
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    • pp.209-218
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    • 1989
  • In order to elucidate the relationship among the several forest types in the green-sbelt nearby Seoul, the vascular plant species data collected preferentially from 52 stands were subjected to DCA (detrended correspondence analysis). Eight types of forests were arranged on the I/II plane fo DCA stand ordination, Quercus mongolica, Alnus hirsuta, Populus alba $\times$ glandulosa, Robinia pseudo-acacia, Pinus densiflora, Pinus koraiensis, Larix leptolepis and pinus rigida forest. Correlation analysis between the stand scores of DCA and environmental factors revealed that the axis I of DCA stand ordination implied the gradient of altitude, organic matter, total nitrogen and depth of A horizon. The axis II implied the gradient of total nitrogen and soluble phosphorus. The results of PCA (principal components analysis) by environmental data were in good agreement with that of DCA by floristic data. The recruitments of Quercus spp. Occurred in all kinds of forest types in the green-belt and their recruitments were closely related with altitutde: Quercus dentata in the foot. Quercus serrata in the midslope and Quercus mongolica in the uperslope of the mountain.

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Landscape Structure and Relationship between Water Quality and Land Use Pattern in the Watershed of the Wangsuk River in Gyunggi-do Korea

  • Lee, Chang-Seok;Lee, An-Na;You, Young-Han
    • The Korean Journal of Ecology
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    • 제24권4호
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    • pp.253-258
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    • 2001
  • Land use pattern in the Wangsuk river watershed was investigated on the bases of physiognomic vegetation maps made from the aerial photograph interpretation and field check. Landscape structure was analyzed using a GIS program supported by ArcView. Landscape structure depended on the geographical position of the river, such as the upper, middle and lower river. Watersheds of the upper and middle rivers were dominated by forests composed of secondary forest and plantation. But agricultural fields dominated that of the middle and lower river. Urban area and agricultural fields increased in from the upper toward the lower river watersheds. In addition to, a transformation of agricultural pattern into an institutional agriculture was characteristic in the middle and lower river basins. Water qualities of the Wangsuk river were usually better in the order of the upper, middle, and lower river, but they were fluctuated according to the site. Such fluctuation would due to self-purification of the river and land use pattern of the watershed as the non-point source. In this viewpoint, a strategy to manage the water quality in the level of watershed is urgently required.

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Fisheries Resources of Sudan

  • Abd El Magid, Magda Ahmed;Elseed, Salah Mahmoud Hamed
    • 한국해양바이오학회지
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    • 제3권1호
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    • pp.42-47
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    • 2008
  • Sudan is the largest country in Africa with an area of $2,505,810km^2$, of water constitutes $129,810km^2$, and cultivable land is 34%. Sudan has a total land boundary of 7,687 km with 9 border countries. This vast country embraces different vegetation patterns reflecting various climatic zones, grading from tropical rain forests in the south through semi-tropical savannah to arid zone in the extreme north, with annual rainfall ranging from 1,600 mm in the south to 25 mm in the north. The aquaculture industry is not developed as yet. Because of their basic characteristics, the Sudan inland and marine capture fisheries are of a small-scale and semi-industrial nature. The demand for fish and fish preparations is growing steadily. The animal resources sector (which includes fisheries) contributes 21% of Sudan GDP. The contribution of fisheries to Sudanese GDP is currently marginal. The per caput supply is only 1.6 kg/year, which is mostly obtained by capture fish landings. Despite the fact that fisheries GDP is extremely low, fish and fish preparations contribute to the food security of a wide sector of the rural and urban communities. Fisheries also provide work opportunities in the form of secondary employment as a source of income that indirectly contributes to household food security.

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대청댐 유역 굴참나무림의 군락분류학 및 군락생태학적 연구 (Syntaxonomy and Synecology of Quercus variabilis Forest in Daecheong-dam basin)

  • 김성열;문건수;송원경;최재용
    • 한국환경복원기술학회지
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    • 제24권6호
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    • pp.15-34
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    • 2021
  • Syntaxonomy and Synecology on Quercus variabilis forests in Daecheong-dam basin was carried out using the methods of Braun-Blanquet phytosociology. 6 syntaxa classified as species compositions described were Quercus variabilis community, Platycarya strobilacea-Quercus variabilis community(typicum subcommunity, dictamnus dasycarpus subcommunity), Quercetum variabili-serratae, Zelkova serrata-Quercus variabilis community and Dendranthema boreale-Quercus variabilis community. All syntaxa were shown habitat environmental conditions including steep inclination of more than 30°, high rock exposure rate of more than 50% and South-facing slope. These communities excepting Dendranthema boreale-Quercus variabilis community classified as natural vegetation were identified as low emergence rate of annual plants and species compositions composed native species, so it was confirmed that relatively natural succession were proceeding well. Quercetum variabili-serratae and Dendranthema boreale-Quercus variabilis community distributed forested hillslope of open water edge were representative Quercus variabilis syntaxa in Daecheong-dam basin.

인왕산(仁王山)의 산림식생단위(山林植生單位)와 경관구조(景觀構造) (Forest Vegetation Units and Landscape Structures of Mt. Inwang in Seoul, Korea)

  • 조현제;조재형;이창석
    • 한국산림과학회지
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    • 제88권3호
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    • pp.342-351
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    • 1999
  • 도시화에 의해 고립된 임지인 인왕산에 발달하고 있는 산림식생이 식물사회학적 방법으로 해석되고 그것의 공간적 분포가 정밀하게 지도화되었다. 정밀식생도상의 patch의 수와 크기를 이용하여 인왕산의 경관구조 특성이 검토되었다. 인왕산지역의 산림식생단위는 10개 군락, 10개군 그리고 8개소군으로 구분되었으며, 경관요소유형은 이차림요소, 유적군락요소, 인공림요소 그리고 도시화지역을 비롯한 기타요소로 구분되었다. 소나무군락과 아까시나무군락이 각각 기질(matrix)을 형성하고 있었으며, 그와 같은 기질내에서 소면적의 일부 이차림, 유적군락 그리고 기타 인공림들이 소규모 patch로 분포하고 있었다. 단위면적당 patch의 수는 이차림요소가 인공림요소보다 많았으며, patch의 크기는 그 반대의 경향이었다. 경관요소유형별 유관속식물의 종풍부성은 patch의 크기와 양의 관련이 있는 것으로 판단되었다. 경관생태학적 검토결과, patch의 분화는 군락수준에서는 인위적 간섭이, 군이나 소군 등 하위군락수준에서는 자연적인 천이과정이 주로 관계하고 있는 것으로 생각되었다.

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제주시험림 한남 지역의 조류 군집 특성 (The Characteristics of Bird Community at Hannam Area of Jeju Experimental Forests)

  • 박찬열;김은미;강창완
    • 한국환경생태학회지
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    • 제25권6호
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    • pp.828-835
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    • 2011
  • 본 연구는 제주시험림 한남지역에서 2006년 11월부터 2007년 9월까지 매월 3일 연속으로 11개월 동안 선조사법에 의한 2개 지역과 정점조사법에 의한 5개 지역을 정하여 이동성, 둥지 길드, 출현비율의 군집 분석을 통하여 조류 군집의 특성을 살펴보았다. 총 58종의 조류를 확인하였으며, 조류를 이동성(migration habit)에 따라 나누면, 텃새 24종, 여름철새 8종, 겨울철새 10종, 나그네새 16종이었다. 대개 육지에서는 여름철새의 종 수가 높지만, 조사지역에서 나그네새 종수가 더 많은 것으로 나타났다. 또한, 월별 출현종의 관찰비율을 군집 분석한 결과, 11월부터 2월의 모둠, 3월~7월의 모둠으로 나누어져 계절성을 보였으나, 월별 종 수 변화는 육지에서 나타나는 계절 변동이 없었다. 번식기와 비번식기에 종 구성은 변화하지만, 전체 종수는 계절 변동을 나타내지 않았다. 이는 나그네새 등 이동성 조류가 제주시 험림을 다수 방문하는 것을 나타낸다. 산림성 조류에게 둥지를 제공하는 딱따구리류는 본 조사지에서는 큰오색딱다구리 1종으로 육지의 5종과 차이를 나타낸다. 둥지 길드는 덤불 및 지면에서 둥지를 튼 새는 9종, 숲지붕층 8종, 나무구멍 7종, 인가에서 번식하는 1종이 기록되었다. 조사지에서 큰오색딱다구리는 박새류, 흰눈썹황금새, 호반새의 둥지를 제공하는 핵심종(keystone species)으로서 이 종을 보호하기 위한 산림시업을 고려해야 할 것으로 판단된다.