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Seroepidemiological Investigation of Lyme Disease and Human Granulocytic Anaplasmosis among People Living in Forest Areas of Eight Provinces in China 被引量:13
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作者 HAO Qin GENG Zhen +10 位作者 HOU Xue Xia TIAN Zhen YANG Xiu Jun JIANG Wei Jia SHI Yan ZHAN Zhi Fei LI Guo Hua YU De Shan WANG Hua Yong XU Jian Guo WAN Kang Lin 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2013年第3期185-189,共5页
Objective Lyme disease and Human granulocytic anaplasmosis are tick-borne diseases caused by Borrelia burgdorferi and Anoplasrna phagocytophilum respectively. We have investigated infection and co-infection of the two... Objective Lyme disease and Human granulocytic anaplasmosis are tick-borne diseases caused by Borrelia burgdorferi and Anoplasrna phagocytophilum respectively. We have investigated infection and co-infection of the two diseases in the population of forest areas of eight provinces in China by measuring seroprevalence of antibodies against B. burgdorferi and A. phagocytophilum. Methods Forest areas in 8 provinces were chosen for investigation using whole sampling and questionnaire survey methods. 3 669 serum samples from people in the forest areas were tested for the presence of antibodies by indirect immunofluorescent assay (IFA). Results Seroprevalence against B. burgdorferi was 3% to 15% and against A. phagocytophilum was 2% to 18% in the study sites in the 8 provinces in China. We also found co-infection of B. burgdorferi and A. phagocytophilum in 7 of the 8 provinces (the exception being the Miyun area in Beijing). The seroprevalence for both B. burgdorferi and A. phagocytophilum was significantly higher among people exposed to ticks than among people who were not exposed to ticks. Conclusion We conclude that both pathogens are endemic in the forest areas in the eight provinces, but the prevalence of B. burgdorferi and A. phagocytophilum differs between the provinces. 展开更多
关键词 Borrelia burgdorferi Anaplasma phagocytophilum CO-INFECTION Residents of forest areas
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Simulation on the dynamics of forest area changes in Northeast China 被引量:11
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作者 DENG Xiangzheng JIANG Qun'ou +2 位作者 ZHAN Jinyan HE Shujin LIN Yingzhi 《Journal of Geographical Sciences》 SCIE CSCD 2010年第4期495-509,共15页
There is plenty of forests in Northeast China which contributes a lot to the conservation of water and land resources, produces timber products, and provides habitats for a huge number of wild animals and plants. With... There is plenty of forests in Northeast China which contributes a lot to the conservation of water and land resources, produces timber products, and provides habitats for a huge number of wild animals and plants. With changes of socio-economic factors as well as the geophysical conditions, there are dramatic changes on the spatial patterns of forest area. In this sense, it is of great significance to shed light on the dynamics of forest area changes to find the underlining reasons for shaping the changing patterns of forest area in Northeast China. To explore the dynamics of forest area change in Northeast China, an econometric model is developed which is composed of three equations identifying forestry production, conversion from open forest to closed forest and conversion from other land uses to closed forest so as to explore the impacts on the forest area changes from demographic, social, economic, location and geophysical factors. On this basis, we employ the Dynamics of Land System (DLS) model to simulate land-use conversions between forest area and non-forest cover and the land-use conversions within the sub-classes of forest area for the period 2000-2020 under business as usual scenario, environmental protection scenario and economic growth scenario. The simulation results show that forest area will expand continuously and there exist various kinds of changing patterns for the sub-classes of forest area, for example, closed forest will expand continuously and open forest and shrub will decrease a little bit, while area of other forest will keep intact. The research results provide meaningful decision-making information for conserving and exploiting the forest resources and makJng out the planning for forestry production Jn the Northeast China region. 展开更多
关键词 forest area forestry production econometric model dynamics of land system Northeast China
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Influence of roads on small rodents population in fragmented forest areas, South Korea
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作者 任信在 李昌培 +4 位作者 许位行 朴容秀 崔瑞允 朴仁珠 李宇新 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第2期155-158,共4页
The road effect on small rodent population is investigated at 8 fragmented forest areas in the Baekdudaegan mountain range, South Korea in September 2001. We especially focused on the distribution and body condition o... The road effect on small rodent population is investigated at 8 fragmented forest areas in the Baekdudaegan mountain range, South Korea in September 2001. We especially focused on the distribution and body condition of small rodents near the roads. Korean field mouse (Apodemus peninsulae) seems to be more sensitive to the existence of a road than striped field mouse (Apodemus agrarius). Korean field mouse prefers interior forest area to around road. Striped field mouse is a habitat generalist and has wide distributional range around road, but Korean field mouse is forest-inhabiting species and their distribution is limited in forest area. These results suggest the effect of road is different on each small rodent species and their habitat preferences. 展开更多
关键词 Fragmented forest area ROAD Small rodents South Korea
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Non-Native Insects in Urban and Forest Areas of Slovenia and the Introduction of Torymus sinensis with Dryocosmus kuriphilus 被引量:2
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作者 Maja Jurc Srdjan Bojovic Dusan Jurc 《Open Journal of Forestry》 2017年第4期416-427,共12页
We survey non-native insects species in whole territory of Slovenia. Data on non-native species were collected in field, and we also used results of projects in which we participated and with overview of literature da... We survey non-native insects species in whole territory of Slovenia. Data on non-native species were collected in field, and we also used results of projects in which we participated and with overview of literature data in scientific pub-lications. Correspondence Analysis (CA) of data was carried out with the soft-ware Statgraphics Centaurion XVI, U.S.A. Up to 254 non-native insect species are present: around 83% are phytophagous (43% feed on woody plants, 40% on other plants);around 12% are non-phytophagous;and 5% are parasitoids or predators of other insects or mammals. Among the phytophagous species, Hemiptera predominates (with 38.2%), followed by Coleoptera (29.8%) and Lepidoptera (14.5%). Non-native insects that do not feed on plants include Coleoptera (80%), Lepidoptera (6.5%), Hymenoptera (6.5%) and Diptera (6.5%). Most of phytophagous species are associated with introduction of plants on which they are specialists, but some have also shifted from introduced to native plant hosts. 36 non-native phytophagous species (14.17% of all non-native insects) have become harmful plant pests of urban trees and crops. 20 appear on woody plants, but only Dryocosmus kuriphilus, appears in urban forest areas. In the past decades species such as D. kuriphilus, Leptoglossus occidentalis, Xylosandrus germanus, Gnathotrichus materiarius, Dasineura gledichiae, Phyllonorycter issikii, Cinara curvipes, Ophiomyia kwansonis have been recorded in parks and forests. Some non-native species are spreading in Slovenian urban forests and affect economic, ecological and other forest and urban forest functions. The number of harmful insects in forests is extremely small probably due to high diversity of the forest ecosystem, where close-to-nature forest management is practiced, which retains forest’s self-regulatory ability to control pests. Such management enables for example the reduction of D. kuriphilus with expansion of its parasitoid, Torymus sinensis. We attempt to explain this phenomenon: we assume that T. sinensis was introduced in Slovenia as diapaused eggs in its host, D. kuriphilus. 展开更多
关键词 Urban forest areas forestS Non-Native Insects Non-Native Parasitoids Dryocosmus kuriphilus Torymus sinensis
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A study on state-owned forest area stakeholders' behavior
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作者 ZHANG Ai-mei CHEN Shao-zhi +2 位作者 WU Wei-hong LI Wen-yu WANG Yang-yang 《Ecological Economy》 2014年第2期164-171,共8页
The development of state-owned forest area plays a very important role in the development of Chinese forest industry, and even in the construction of national economy. As the backbone of Chinese forestry development, ... The development of state-owned forest area plays a very important role in the development of Chinese forest industry, and even in the construction of national economy. As the backbone of Chinese forestry development, it contributes to Chinese economic development, ecological environment protection and social progress. How to balance all stakeholders' interest and behaviors remains as one of the focuses in the study of sustainable development of forest areas. On this basis, researches were carried out and described in the paper. Firstly, the paper goes through the concept and scope of state-owned forest area in China; Secondly, it defines the stakeholders of state-owned forest area, and discusses over the problems in stakeholders' behaviors from the aspect of responsibility, rights and interests; and Finally, it designs the stakeholders' behaviors on the basis of existing problems and provides constructive suggestions on deeper reform of state-owned forest areas. 展开更多
关键词 stakeholders' behaviors state-owned forest area China
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LAND RESOURCE CHARACTERISTICS AND RATIONAL LAND-USE ARRANGEMENT FOR FARMING,FORESTRY AND ANIMAL HUSBANDRY IN “THREE NORTHS” SHELTER FOREST AREA
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作者 Shen Yuancun Institute of Geography, Chinese Academy of Sciences, Beijing, 100101 《干旱区资源与环境》 CSCD 1993年第Z1期125-128,共4页
The "Three Norths" (Northeastern China, Northern China, and Northwestern China)Shelter forest area is located in the north part of china. The area of this region occupies41% of the total area of China. This ... The "Three Norths" (Northeastern China, Northern China, and Northwestern China)Shelter forest area is located in the north part of china. The area of this region occupies41% of the total area of China. This region is eager for being managed because of its fragileecological conditions. Therefore, the basic approach to realize the harmonious developmentof ecological and economic benefits is the rational arrangement of farming, forestry and pas-ure land according to the characteristics of land resources of this region. 展开更多
关键词 "Three Norths" SHELTER forest area LAND Resources LAND RESTRICTIVE Factor LAND Arrangement for Agriculture forestRY and Animal HUSBANDRY
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Cultivation of Black Fungus under Forest in Middle-high Altitude Areas
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作者 袁长波 徐延熙 +5 位作者 王艳芹 姚利 付龙云 田叶 李瑞琴 曹德宾 《Agricultural Science & Technology》 CAS 2016年第10期2358-2361,共4页
[Objective] The study was to solve the contradiction between fungus and forest during the production of black fungi, and to obtain relatively high economic benefits and ecological benefits. [Method] Black fungi were c... [Objective] The study was to solve the contradiction between fungus and forest during the production of black fungi, and to obtain relatively high economic benefits and ecological benefits. [Method] Black fungi were cultivated in forest with middle-high altitude of 500-1 600 m. The germination time of fungus stick, germination days of buds, growth days of fruiting body, commodity exterior, marketing effect and biological efficiency of black fungi were investigated. [Result] Compared with traditional cultivation, black fungus products cultivated under forest had the taste and flavor of wild black fungus. Fungus chaff wastage was directly decomposed by the roots in forest land, improving the soil structure of forest land. The need of moisture retention and the frequent access of administrative staff reduced the probability of forest fire occurrence. [Conclusion] Cultivation of black fungus under forest saves more than 70% fixed-asset investment on fungus shed, and the biological efficiency reached 12.2%. 展开更多
关键词 forest area in middle-high altitude Under forest Black Fungus
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Study on the Forest Vegetation and Its Water and Soil Conservation Value in Fuxian Lake Drainage Area in Yunnan Province 被引量:5
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作者 艾建林 温庆忠 陶晶 《Meteorological and Environmental Research》 CAS 2010年第10期58-61,共4页
By using French SPOT5 satellite remote sensing image to contrast on the spot,the forest vegetation in Fuxian Lake basin was categorized into 23 forest types,6 vegetation subtypes,5 vegetation types,and the areas were ... By using French SPOT5 satellite remote sensing image to contrast on the spot,the forest vegetation in Fuxian Lake basin was categorized into 23 forest types,6 vegetation subtypes,5 vegetation types,and the areas were respectively calculated.The tree species structure and the coverage degree of every kind of forest vegetation were investigated,and the characteristics of forest vegetation were analyzed.The results showed that the soil conservation amount of forest in Fuxian Lake basin was 137.50×106 t/a,and the soil conservation value was 622.30×106 yuan/a.Moreover,the water source conservation value was 506.84×106 yuan/a. 展开更多
关键词 Fuxian Lake forest vegetation area Soil conservation value Water source conservation value China
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Factorial analysis on forest canopy density restoration in the burned area of northern Great Xing'an Mountains, China 被引量:2
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作者 XIEFu-ju XIAODu-ning +2 位作者 LIXiu-zhen WANGXu-gao SHIBao-dong 《Journal of Forestry Research》 SCIE CAS CSCD 2005年第2期125-131,共7页
The restoration of forest landscape has drawn much attention since thecatastrophic fire took place on the northern slope of Great Xing'an Mountains in 1987. Forest canopydensity, which has close relation to forest... The restoration of forest landscape has drawn much attention since thecatastrophic fire took place on the northern slope of Great Xing'an Mountains in 1987. Forest canopydensity, which has close relation to forest productivity, was selected as a key factor to find howmuch the forest quality was changed 13 years after fire, and how fire severity, regeneration way andterrain factors influenced the restoration of forest canopy density, based on forest inventory datain China, and using Kendall Bivariate Correlation Analysis, and Distances Correlation Analysis. Theresults showed that fire severity which was inversely correlated with forest canopy density gradewas an initial factor among all that selected. Regeneration way which did not remarkably affectforest canopy density restoration in short period, may shorten the cycle of forest succession andpromote the forest productivity of conophorium in the future. Among the three terrain factors, theeffect of slope was the strongest, the position on slope was the second and the aspect was the last. 展开更多
关键词 forest fire burned area productivity restoration forest canopy density factorial analysis kendall correlation analysis
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Quantitative Simulation of Dynamic Changes in Cultivated Land in Areas of Reclamation and Returning Cultivated Land to Forest or Pastures under RCPs Climate Scenarios 被引量:1
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作者 刘唯清 齐元静 +1 位作者 姜群鸥 聂承静 《Agricultural Science & Technology》 CAS 2016年第1期178-187,共10页
Northeast China as one of important agricultural production bases is an area under reclamation and returning cultivated land to forests or pastures. Therefore, it is of great practical significance in guaranteeing the... Northeast China as one of important agricultural production bases is an area under reclamation and returning cultivated land to forests or pastures. Therefore, it is of great practical significance in guaranteeing the sustainable development and national food security to study the spatial and temporal variation of cultivated land in Northeast China under future climate scenarios. In this study, based on data of land use, natural environment and social-economy, dynamics of land system(DLS) model was used to to simulate the spatial distribution and changing trends of cultivated land in the typical areas of reclamation and returning cultivated land to forest or pastures in Northeast China during 2010-2030 under land use planning scenario and representative concentration pathways(RCPs) scenarios quantitatively.The results showed that the area of cultivated land had an overall decreasing trend under the land use planning scenario, but the area of upland field increased slightly from 2000 to 2010 and then declined greatly, while the area of paddy field continuously declined from 2000 to 2030. Under the Asia-Pacific Integrated model(AIM)scenario, the total area of cultivated land had a tendency to increase considerably,with the upland field expanding more obviously and the paddy field declining slightly.In addition, the cultivated land showed a greater decreasing trend under the model for energy supply strategy alternatives and their general environmental impact(MESSAGE) scenario compared to the land use planning scenario. Moreover, analysis on the conversion between different land use types indicated that the reclamation and returning cultivated land to forests or pastures was likely to continue under future scenarios, but the frequency of occurrence could decrease as the time goes by. The conclusions can provide significant decision-making information for the rational agricultural planning and cultivated land protection in Northeast China to adapt to the climate change. 展开更多
关键词 Land use Climate change Planning Cultivated land change Quantitative simulation Scenario areas of reclamation and returning cultivated land to forest or pastures
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Study on the Development of Under-forest Economy in Guangdong Mountain Areas 被引量:2
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作者 Jing CHEN Hongou ZHANG Qitao WU 《Asian Agricultural Research》 2015年第4期45-50,共6页
From the origin and connotation of the under-forest economy,this paper analyzed plight of the development of under-forest economy in Guangdong mountain areas. It discussed benefits of under-forest economy,favorable co... From the origin and connotation of the under-forest economy,this paper analyzed plight of the development of under-forest economy in Guangdong mountain areas. It discussed benefits of under-forest economy,favorable conditions and development path of under-forest economy in Guangdong mountain areas. Results indicate that developing under-forest economy is an essential path for realizing green growth and coordinated development of Guangdong mountain areas. However,due to terrain,market,management and technology reasons,the under-forest economy is still not fully developed in Guangdong mountain areas. The development path of under-forest economy suitable for Guangdong mountain areas should be based on ecological protection and oriented towards maximizing ecological,economic and social benefits. Guangdong mountain areas have in-born natural and resource advantages,economic pull of development mode and market demand change,and favorable condition of policy encouragement for development of under-forest economy. Finally,it came up with recommendations for development of under-forest economy in Guangdong mountain areas from development mode,industrial distribution and development direction. 展开更多
关键词 GUANGDONG MOUNTAIN areas Under-forest ECONOMY Deve
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Evaluation of the forest ecosystem health in Beijing area 被引量:1
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作者 Ma Li Han Hai-rong Ma Qin-yan Liu Hong-wen Xia Wei-wei Cheng Xiao-qin 《Forestry Studies in China》 CAS 2007年第2期157-163,共7页
The evaluation of ecosystem health has become one of the main research topics of ecosystem science, thus more and more assessment methods and frameworks have been put forward in recent years. However, the attention pe... The evaluation of ecosystem health has become one of the main research topics of ecosystem science, thus more and more assessment methods and frameworks have been put forward in recent years. However, the attention people pay to ecosystem health is actually more about what the social functions the ecosystem affords, which depend on the integrity and maintenance of the ecosystem structure and function, and the intensity of disturbance from outside. Accordingly, this research commenced from three main aspects, selected the evaluation indices, and then established the Evaluation Index System of Beijing Forest Ecosystem Health (EIS-BFEH). In the EIS-BFEH, each of the three foundations contained an easily-operated and standard sub-index system, which compounded the specific natural and social conditions of Beijing and was concrete enough to measure and evaluate. Then with the method of the Analytical Hierarchy Process (AHP), the comprehensive index (CI) could be obtained, which represented the health of the forest ecosystem. As a case study, the forest ecosystems in the Badaling area were sampled, evaluated, compared and ranked by use of the EIS-BFEH. The result show that the health of natural forests is much better than that of plantations in the Badaling forest center: the average comprehensive index of the former is 7.9, while the latter is only 6.6. From the results, it could also be found that there are nine units in the healthy state, two units in the subhealthy state, and only one unit of Robiniapseudoacacia in the morbid state. 展开更多
关键词 Beijing area forest ecosystem health EVALUATION Badaling forest Center
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Energy of forest systems in the Three Gorge Reservoir area 被引量:1
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作者 Wu Gang, Su Rui ping Department of Systems Ecology, Research Center for Eco Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1999年第1期110-114,共5页
The energies of three forest ecosystems in the Three Gorge Reservoir area were analyzed. The results showed that the existing energies were 151 2438, 139 2014 and 175 1659 (×10 10 J/hm 2), the annual ne... The energies of three forest ecosystems in the Three Gorge Reservoir area were analyzed. The results showed that the existing energies were 151 2438, 139 2014 and 175 1659 (×10 10 J/hm 2), the annual net fixed energies were 38 8924, 31 2214 and 46 8231 (×10 10 J/hm 2), and the utilization efficiency of light energies were 1 16, 0 99 and 1 40 for the Quercus acutissima forest(Q.A.), the Pinus massoniana forest (P.M.), and the Queresus acutissima and Pinus massoniana mixed forest (Q.P.), respectively. In the Three Gorge Reservoir Area, the energy efficiency of Quercus acutissima and Pinus massoniana mixed forest is the best. 展开更多
关键词 forest ecosystem ENERGY Three Gorge Reservoir area.
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Forest Wetland Area and the Forest Sector Economy in the U.S. South
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作者 Frederick Cubbage Robert Abt +2 位作者 Ray Sheffield Curt Flather James Wickham 《Open Journal of Forestry》 2018年第3期409-428,共20页
This article reviews current data on forest wetlands and their economic contributions in the South, ranging from Texas to Virginia. Based on USDA Forest Service Forest Inventory and Analysis (FIA) data, the wetland ca... This article reviews current data on forest wetlands and their economic contributions in the South, ranging from Texas to Virginia. Based on USDA Forest Service Forest Inventory and Analysis (FIA) data, the wetland category comprised 17.7% of timber land area on all private and public lands in the South. This included 4.25 million ha of hydric sites;0.77 million ha mesic wet;9.55 million ha mesic, with only seasonal access;for a total of 14.57 million ha. The Natural Resource Inventory (NRI) for 2012 on private lands estimated that there were 14.71 million ha forested wetlands, which comprised 17.7% of all forested private forest area. The 2015 National Land Cover Data for the South estimated that there were 17.8 million ha of woody wetlands, which comprised 8% to 12% of the southern land area, and there were also 4.45 million ha of emergent herbaceous sites. About 10% of the southern timber forest sector would be based on harvests from wetland forests economy ($455 million per year), while the 17.7% of wetland land area would provide a proportional share of the annual nontimber forest products ($44 million) and payments for ecosystem services ($134 million). Wetlands also provide important nontimber forest products, and ecosystem services, which are beginning to develop active private and public markets. 展开更多
关键词 forest WETLANDS area ECONOMICS VALUATION
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DISCUSSIONS ON FOREST RECOVERY IN THE BURNED AREA IN DAXING'ANLING FOREST REGION
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作者 潘建平 《Journal of Northeast Forestry University》 SCIE CAS CSCD 1995年第1期23-26,共4页
The disastrous fire occurred in northern area of Daxing’anling forest region on May 6, 1987, destroyed a large area of forests. The broad-leaved tree species, such as poplar,birch had regenerated in a great quantity ... The disastrous fire occurred in northern area of Daxing’anling forest region on May 6, 1987, destroyed a large area of forests. The broad-leaved tree species, such as poplar,birch had regenerated in a great quantity after the fire, but the coniferous species such as larch and scotch pine had difficult to regenerate naturally, This paper put forward that the coniferous forest could be recovered by the planting method of effect strip and effect islet based on the principle of borderline effects and by making full use of the condition of broad-leaved trees. 展开更多
关键词 BORDERLINE EFFECT Burned area forest FIRE forest RECOVERY
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Estimation of Basal Area in West Oak Forests of Iran Using Remote Sensing Imagery
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作者 Loghman Ghahramany Parviz Fatehi Hedayat Ghazanfari 《International Journal of Geosciences》 2012年第2期398-403,共6页
The objective of this study is to evaluate the capability of satellite imagery for the estimation of basal area in Northern Zagros Forests. The data of the high resolution geometric (HRG) sensor of SPOT-5 satellite da... The objective of this study is to evaluate the capability of satellite imagery for the estimation of basal area in Northern Zagros Forests. The data of the high resolution geometric (HRG) sensor of SPOT-5 satellite dated in July 2005 were used. Investigation of the quality of Satellite images shows that these images have no radiometric distortion. Overlaying of geocoded images with the digital topographic maps indicated that the images have high geometric precision. A number of 319 circular plots (0.1 ha) were established using systematic random method in the study area. All trees having diameter at breast height (DBH) (i.e. 1.3 m above ground) greater than 5 cm were callipered in each plot. Basal area in each plot was determined using field data. Main bands, artificial bands such as vegetation indices and principle component analysis (PCA) were studied. Digital numbers related to each plot were extracted from original and artificial bands. All plots were ordinated by major geographic aspects and the best fitted regression models were determined for both the study area without consideration of aspects and with consideration of major geographic aspects by multiple regression analysis (step wise regression). The results from regression analysis indicated that the square root of basal area without consideration of aspects has a high correlation with band B1 (r = –0.60). The consideration of aspects resulted in correlation of different indices with square root of basal area such that in northern forests, band B1 had higher correlation coefficient(r = –0.67) among other indices. In Eastern forests, the same band showed correlation of basal area with different correlation coefficient (r = –0.65). In southern and western forests, the square root of basal area had higher correlation (r = –0.68) with RVI. The use of the square root of basal area as a dependent variable in multivariate linear regression improved the results. The assessment of model validity indicated that the proposed models are properly valid. 展开更多
关键词 NORTHERN ZAGROS forestS BASAL area SPOT-5 Data
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Species composition and minimum sampling area of a riparian mixed broadleaved-Korean pine forest in Changbai Mountain Nature Reserve
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作者 DAI Fang-zhou XU Dong DENG Hong-bing 《Journal of Forestry Research》 SCIE CAS CSCD 2011年第3期471-474,共4页
Riparian areas are unique although often small component of the overall watershed landscape. The structure of riparian forests along Erdaobai River on the north slope of Changbai Mountain were investigated by using fi... Riparian areas are unique although often small component of the overall watershed landscape. The structure of riparian forests along Erdaobai River on the north slope of Changbai Mountain were investigated by using field data collected from eight sampling transects perpendicular to the Erdaobai River channel. Two kinds of species-area saturation curves were used to examine the relationship between species number and minimum sampling area. The results showed that riparian gymnosperms accounted for a high proportion of all gymnosperms in the Changbai Mountain Nature Reserve while riparian ferns and angiosperms accounted for a relatively low proportion. The average minimum sampling areas of riparian forest that included 60%, 80%, and 90% of the community species pool were about 85, 185, and 328 m 2 , respectively; while those for nonriparian forest were about 275, 390, and 514 m 2 , correspondingly. 展开更多
关键词 mixed broadleaved-Korean pine forest minimum sampling area ecosystem management Changbai Mountain
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Analysis of Landscape Patterns and the Trend of Forest Resources in the Three Gorges Reservoir Area
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作者 Wei Wang Ying Pu 《Journal of Geoscience and Environment Protection》 2018年第5期181-192,共12页
In this paper, first, based on landscape ecology theories, we respectively selected indexes from 4 aspects, area, edge, shape, and density, of the landscape type to describe the status of forest landscape patterns, an... In this paper, first, based on landscape ecology theories, we respectively selected indexes from 4 aspects, area, edge, shape, and density, of the landscape type to describe the status of forest landscape patterns, and we established the stability index of landscape pattern (LSBI). Then, based on geo-statistical theories, we divided the forest in the reservoir area into 3990 grids of 4 km × 4 km using network technology and employing ordinary Kriging modelling to make trend surface analyses of the forest resources in the reservoir area. Finally, based on statistics principles, we used sampling theory to systematically extract 227 samples to obtain 7 periods of remote-sensing data from 1990a to 2012a. Then, we classified and extracted the forest in the sampling area using remote sensing, and we analysed each result with an Autoregressive Integrated Moving Average Model (ARIMA) time-series model. The results indicated the following: 1) the landscape structure of the reservoir area was primarily needle-leaved forest, broad-leaved forest and bush forest, and the mixed stands and bamboo stands were secondary;2) the difference of the forest landscape pattern stability in the reservoir area, in all directions, was not significant, but the southern region was slightly more stable;and 3) the stability of the forest landscape pattern in the reservoir area increased from 1990a to 2012a. It kept increasing until 2016a. This study provides a theoretical basis for the reasonable management and decisions about the forest resources in the Three Gorges Reservoir Area. Meanwhile, it also explores methods for relevant research and has practical significance. 展开更多
关键词 Three Gorges RESERVOIR area forest RESOURCES LANDSCAPE Pattern TREND ANALYSIS
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Study on Farmers' Cognition and Willingness to Plant Trees during Collective Forest Right Reform Based on Data from Plain Areas of Henan Province
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作者 Min LIU Shaozhou ZHOU 《Asian Agricultural Research》 2013年第6期14-18,23,共6页
On the basis of the survey data from plain areas of Henan Province,farmers' cognition and willingness to plant trees in collective forest right reform are studied. According to statistical analysis and regression ... On the basis of the survey data from plain areas of Henan Province,farmers' cognition and willingness to plant trees in collective forest right reform are studied. According to statistical analysis and regression equation of binary logistic regress analysis,it is generally believed that different participants have various attitudes to the reform,with regard to if planting trees or more,reform variables have a distinct effect,as well as income variable and loaning or lending variable. At last,some advices are put forward,that is,the government should strengthen collective forest right reform,accelerate matching reform and increase policy and financial support to forestry farmers. 展开更多
关键词 COLLECTIVE forest right system Plain areas PERFORM
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Quantitative Evaluation of Bitterlich Sampling for Estimating Basal Area in Sparse Boreal Forests and Dense Tropical Forests
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作者 Wei Yang Hideki Kobayashi +2 位作者 Kenlo Nishida Nasahara Rikie Suzuki Akihiko Kondoh 《Open Journal of Forestry》 2017年第2期143-156,共14页
Bitterlich sampling is an extensively used technique in worldwide forest inventories. Although it has been proved that estimates of basal area from Bitterlich sampling are mathematically unbiased, its precision for in... Bitterlich sampling is an extensively used technique in worldwide forest inventories. Although it has been proved that estimates of basal area from Bitterlich sampling are mathematically unbiased, its precision for individual forest stands may be fairly poor. An extension of validation efforts to different forest biomes could therefore provide more comprehensive assessment and understanding of the Bitterlich sampling technique. In this study, this technique was quantitatively evaluated by using simulated sparse boreal forests and dense tropical forests from an empirical forest structure model (EFSM). Theoretical estimation of basal areas and practical estimation influenced by the hidden-tree effect were both compared with true basal areas of the simulated forests. The evaluation results indicated that: 1) Bitterlich sampling can yield acceptable accuracy and precision when the count number (CN) of trees was set to 10 for the studied boreal and tropical forests with distinct characteristics, 2) the theoretical estimation of basal area can be improved by increasing the CN values for both forests, and 3) when the hidden-tree effect is encountered, the accuracy for tropical forests will be decreased by increasing the CN values, whereas the accuracy for boreal forests can still be improved. Accordingly, a relatively high CN, at a reasonable cost, is recommended for sparse boreal forests to improve the accuracy of basal area estimation. In contrast, for dense tropical forests, a CN of ten is appropriate to mitigate the hidden-tree effect. 展开更多
关键词 Angle-Count Sampling BASAL area forest Structure Modeling BOREAL forestS TROPICAL forestS
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