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Demographic variation and habitat specialization of tree species in a diverse tropical forest of Cameroon 被引量:1
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作者 David Kenfack George B Chuyong +2 位作者 Richard Condit Sabrina E Russo Duncan W Thomas 《Forest Ecosystems》 SCIE CAS 2014年第4期201-213,共13页
Background: Many tree species in tropical forests have distributions tracking local ridge-slope-valley topography. Previous work in a 50-ha plot in Korup National Park, Cameroon, demonstrated that 272 species, or 63%... Background: Many tree species in tropical forests have distributions tracking local ridge-slope-valley topography. Previous work in a 50-ha plot in Korup National Park, Cameroon, demonstrated that 272 species, or 63% of those tested, were significantly associated with topography. Methods: We used two censuses of 329,000 trees ≥1 cm dbh to examine demographic variation at this site that would account for those observed habitat preferences. We tested two predictions. First, within a given topographic habitat, species specializing on that habitat ('residents') should outperform species that are specialists of other habitats ('foreigners'). Second, across different topographic habitats, species should perform best in the habitat on which they specialize ('home') compared to other habitats ('away'). Species' performance was estimated using growth and mortality rates. Results: In hierarchical models with species identity as a random effect, we found no evidence of a demographic advantage to resident species. Indeed, growth rates were most often higher for foreign species. Similarly, comparisons of species on their home vs. away habitats revealed no sign of a performance advantage on the home habitat. Conclusions" We reject the hypothesis that species distributions along a ridge-valley catena at Korup are caused by species differences in trees _〉1 cm dbh. Since there must be a demographic cause for habitat specialization, we offer three alternatives. First, the demographic advantage specialists have at home occurs at the reproductive or seedling stage, in sizes smaller than we census in the forest plot. Second, species may have higher performance on their preferred habitat when density is low, but when population builds up, there are negative density-dependent feedbacks that reduce performance. Third, demographic filtering may be produced by extreme environmental conditions that we did not observe during the census interval. 展开更多
关键词 TREE Demographic variation and habitat specialization of tree species in a diverse tropical forest of Cameroon FIGURE
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The Relationships among Community Type, Peat Layer Thickness, Belowground Carbon Storage and Habitat Age of Mangrove Forests in Pohnpei Island, Micronesia
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作者 Kiyoshi Fujimoto Yukira Mochida +3 位作者 Takao Kikuchi Ryuichi Tabuchi Yasumasa Hirata Saimon Lihpai 《Open Journal of Forestry》 2015年第1期48-56,共9页
This paper quantifies the relationships among community type, peat layer thickness and habitat age of the mangrove forests in Pohnpei Island, Micronesia and provides a discussion concerning the primary succession and ... This paper quantifies the relationships among community type, peat layer thickness and habitat age of the mangrove forests in Pohnpei Island, Micronesia and provides a discussion concerning the primary succession and the belowground carbon storage of the main mangrove community types. The ages of the habitat were estimated from a relationship between the thickness of the mangrove peat layer and the formative period, which was decided by calibrated radiocarbon ages. Mangrove communities in the coral reef type habitat were generally arranged in the following order, from seaward to landward: 1) the Rhizophora stylosa or Sonneratia alba community (I or II communities), 2) the typical subunit of the S. alba subcommunity of the Rhizophora apiculata— Bruguiera gymnorrhiza community (III(2)a subunit) and 3) the Xylocarpus granatum subunit of the same subcommunity of the same community (III(2)b subunit). Their habitat ages were estimated to be younger than 460 years, between 360 and 1070 years and between 860 and 2300 years, respectively. Based on these results and other evidences such as photosynthetic characteristics and pollen analysis derived from the previous studies, the primary succession was inferred to have progressed in the order mentioned above. Belowground stored carbon for the main community types in the coral reef type habitat were estimated to be less than 370 t C ha-1 for the I and the II communities, between 290 and 860 t C ha-1 for the III(2)a subunit and between 700 and 1850 t C ha-1 for the III(2)b subunit. 展开更多
关键词 MANGROVE forest Community Type habitat Age BELOWGROUND Carbon Storage Primary SUCCESSION
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Guidelines for Managing Wildlife Habitats in Southwestern Ponderosa Pine Forests of the United States
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作者 PeterF.Ffolliott 《Journal of Forestry Research》 SCIE CAS CSCD 1997年第2期108-110,共3页
Forest management practices, particularly timber harvesting activities, affect the habitats of a large numberof wildlde species found in southwestem ponderosa pine forests of the United States. Timber harvesting activ... Forest management practices, particularly timber harvesting activities, affect the habitats of a large numberof wildlde species found in southwestem ponderosa pine forests of the United States. Timber harvesting activities and othervegetative treatments offen change the relative abundances of food and cover. Wildlife habitats for some wildlife Species arebenefited, while the habitats for other wildlife species are detrimentally impacted. The guidelines presented in this papershould be helpful to foresters, wildlffe managers, and other interested in maintaining or increasing wildlife habitat qualitiesin the foreSt ecosystems inveStigated. While the wildlde species considered are indigenous to the southwestem ponderosapine fotests, many of the wildlde management principles implied in the guidelines are likely to have applications in otherecosystems throughout the world. 展开更多
关键词 WILDLIFE habitat Resourse Ponderosa pine forest
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Degradation of Primate Habitat at Tesso Nilo Forest with Special Emphasis on Riau Pale-Thighed Surili (<i>Presbytis siamensis cana</i>)
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作者 Jatna Supriatna Sri Mariati 《Journal of Environmental Protection》 2014年第12期1145-1152,共8页
The habitat of Riau pale-thighed surili (Presbytis siamensis cana) located in Riau province of Sumatra island between Siak in the north and Indragiri rivers in the south, has been seriously degraded in the last a few ... The habitat of Riau pale-thighed surili (Presbytis siamensis cana) located in Riau province of Sumatra island between Siak in the north and Indragiri rivers in the south, has been seriously degraded in the last a few decades. This swampy peat land forest has been degraded by frequent burning during the dry season. These problems originated because of poor governance on the forest management, and the construction of two access roads by the owners of logging concessions and wood pulp plantations. This forest block consists of Tesso Nilo National Park, Kerumutan protected area, Production Forest areas belong to two companies, and a small recreation Park. It also contains one of the most important mixed peat swamp forests. Here, we tracked changes in forest cover before and after road construction using GIS and remote sensing imagery. Deforestation rates have increased from 1.5% per year before road construction to 9.28% per year after road construction, which means that the area of forest has decreased by an annual average of 8156 ha in Tesso Nillo alone. The habitat of Riau pale-thighed surili decreased almost up to 60% in the last decade after companies started their converting forest for oil palm and acacia and roads were built crisscrossed. If the trend of deforestation continues, further decline of population of habitat of this species is unavoided. Researches should be carried out in more details to understand the status of population of this subspecies before this subspecies disappears in the wild. 展开更多
关键词 Deforestation PRIMATE habitat Tesso Nilo forest PRESBYTIS siamensis cana Sumatra Indonesia
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Community Characteristics of Wild Fruit Forests Along Elevation Gradients and the Relationships Between the Wild Fruit Forests and Environments in the Keguqin Mountain Region ofⅠii 被引量:4
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作者 ZHUANG Li TIAN Zhonping +3 位作者 CHEN Yaning LI Weihong LI Jiangui LU Shuang 《Journal of Mountain Science》 SCIE CSCD 2012年第1期115-126,共12页
In this paper,the quantitative relationship between the wild fruit communities and direct environmental factors is discussed on the basis of detailed data on landscape scale habitats obtained through field vegetation ... In this paper,the quantitative relationship between the wild fruit communities and direct environmental factors is discussed on the basis of detailed data on landscape scale habitats obtained through field vegetation investigation.The results from TWINSPAN and DCCA showed that:1) In the distribution sections of the wild fruit forest in the Keguqin Mountain region,the basic patterns characteristic of the different habitats are due to topographic factors,nutrients and moisture conditions;2) The elevation affected the most basic differentiation of plant communities in the study area,indicating that the elevation condition was the most important factor restricting the distribution of the wild fruit communities in the study area;3) The close relationship between the moisture content in the upper soil layer and the elevation reflected the influence of moisture conditions on both wild fruit and herb-layer communities;4) Nutrient differences not only indicated that the habitat conditions were different in themselves but also showed that the present nutrient conditions of the habitats were seriously affected by human activities.In summary,under complicated mountainous topographic conditions,the habitat conditions for the communities differed very significantly,and the combination of elevation,soil moisture content,total nitrogen,slope aspect,and pH value influenced and controlled the formation of community distribution patterns in the study area. 展开更多
关键词 Keguqin Mountain Wild fruit forest habitat condition Community distribution pattern DCCA Keguqin Mountain China
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Soil quality index as a tool for Scots pine(Pinus sylvestris) monoculture conversion planning on afforested,reclaimed mine land
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作者 Marcin Pietrzykowski 《Journal of Forestry Research》 SCIE CAS CSCD 2014年第1期63-74,共12页
In Central Europe, a large portion of post-mining sites were afforested with Scots pine, which is characterized by good adaptability and a tolerance for poor habitat at the beginning of forest ecosystem development. C... In Central Europe, a large portion of post-mining sites were afforested with Scots pine, which is characterized by good adaptability and a tolerance for poor habitat at the beginning of forest ecosystem development. Conversion of monoculture on mine sites into more biodi- verse mixed hardwood forests, especially on more fertile deposits, can be an emerging need in this part of Europe in next decades. The ability to classify the forests at these post-mining sites will facilitate proper species selection as well as the management and formation of the developed ecosystem's stability. This work describes the guidelines that can be followed to assess reclaimed mine soil (RMS) quality, using the mine soil quality index (MSQI) and a classification of developed forest sites as a basis of tree-stand species selection and conversion of pine monocul- tures. The research was conducted on four post-mining facilities (lignite, hard coal, sulphur, and sand pit mining areas) on different RMS sub- strates dominant in Central Europe. Soil quality assessment takes into account the following features of the soil: texture soil nutrients (Ca, Mg, K, Na, P); acidity (pH KC1); and Corg-to-Nt ratio in the initial organic horizon. An analysis was conducted of classification systems using the MSQI validation correlation (at p =0.05) with vegetation features af- fected by succession: aboveground biomass of forest floor and ecological indicators of vascular plants (calculated on the basis of EUenberg's (2009) system). Eventually, in the analysed data set, the MSQI ranged from 0.270 for soils on quaternary sands to 0.720 for a mix of quaternary loamy sands with neogene clays. Potential forest habitat types and the role of the pine in the next generation of tree stands on different RMS parent rock substrate were proposed. 展开更多
关键词 mining sites AFforestATION pine monoculture conversion soil quality index forest habitat classification.
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THE NORTHERN FOREST IN THE PEOPLE’S REPUBLIC OF CHINA
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作者 Li Jingwen Ge Jianping Northeast Forestry University 《Journal of Northeast Forestry University》 SCIE CAS CSCD 1992年第1期11-15,共5页
The northern forests of are main1y inc1uded two northern forest regions in theNortheast and the Northwest of China.The first region can be subdivided into the boreal conifer and deciduous forest district of the Great ... The northern forests of are main1y inc1uded two northern forest regions in theNortheast and the Northwest of China.The first region can be subdivided into the boreal conifer and deciduous forest district of the Great Xing’an Mountains and the conifer and deciduous forest district ofLesser Xing’an Mountains;thc second one can be subdivbided into the Northern Montane forest dis-trict of Tianshan Mountains and the Northern Montane coniferous forcst district.It gives a com-pregesive description for the environmental characters,distribution of vegetation and main treespecies of the four distriets. 展开更多
关键词 NORTHERN forest habitat DIVERSITY Distribution VEGETATION
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Thinning and in-stream wood recruitment in riparian second growth forests in coastal Oregon and the use of buffers and tree tipping as mitigation
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作者 Lee E.Benda S.E.Litschert +1 位作者 Gordon Reeves Robert Pabst 《Journal of Forestry Research》 SCIE CAS CSCD 2016年第4期821-836,共16页
Many aquatic habitats in coastal Oregon have been impacted by historic land use practices that led to losses of in-stream wood and associated degraded fish habitats. Many of these streams are now bordered by stands of... Many aquatic habitats in coastal Oregon have been impacted by historic land use practices that led to losses of in-stream wood and associated degraded fish habitats. Many of these streams are now bordered by stands of dense second growth forests(30–80 years) that are incorporated into riparian buffer zones with low wood recruitment and storage. Thinning in riparian zones is one management option to increase the rate of large tree growth and eventually larger in-stream wood, however, it raises concern about impacts on current wood recruitment, among other issues. Using a forest growth simulation model coupled to a model of in-stream wood recruitment, we explore riparian management alternatives in a Douglas-fir plantation in coastal Oregon. Alternatives included:(1) no treatment,(2) single and double entry thinning, without and with a 10-m buffer, and(3) thinning combined with mechanical introduction of some portion of the thinned trees into the stream(tree tipping). Compared to no treatment, single and double entry thinning on one side of a channel, without a 10-m buffer, reduce cumulative instream wood volume by 33 and 42 %, respectively, after100 years(includes decay). Maintaining a 10-m buffer reduces the in-stream wood loss to 7 %(single entry thin)and 11 %(double entry). To completely offset the losses of in-stream wood in a single entry thin(on one or both sides of the stream), in the absence or presence of a 10-m buffer,requires a 12–14 % rate of tree tipping. Relative to the notreatment alternative, cumulative in-stream wood storage can be increased up to 24 % in a double-entry thin with no buffer by tipping 15–20 % of the thinned trees(increased to 48 % if thinning and tipping simultaneously on both sides of the stream). The predicted increases in in-stream wood that can occur during a thin with tree tipping may be effective for restoring fish habitat, particularly in aquatic systems that have poor habitat conditions and low levels of in-stream wood due to historic land use activities. 展开更多
关键词 thinning mitigation coastal Oregon forests habitat piece plantation stands cumulative
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Does Linear Canopy Openings in a Lowland Atlantic Tropical Forest Cause Edge Effects on Seedling Communities?
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作者 Pablo J. F. Pena Rodrigues Mariana A. Iguatemy Marcelo T. Nascimento 《Open Journal of Ecology》 2014年第15期945-949,共5页
Edge effects and linear canopy openings may change ecological patterns and processes on forests. Here we investigate if these openings in a lowland Brazilian Atlantic forest cause edge effects on seedlings. We sampled... Edge effects and linear canopy openings may change ecological patterns and processes on forests. Here we investigate if these openings in a lowland Brazilian Atlantic forest cause edge effects on seedlings. We sampled seedling communities at forest edges near to two linear canopy openings (gas pipeline and power line) and in interiors far from edges. Comparisons between the seedling communities were performed to access edge effects. Density and basal area patterns were compared using, hierarchical two-way ANOVAs and the number of newly germinated seedlings, mortality and resprouts were compared by one-way ANOVAs. The results showed that edge effects of linear canopy openings affect seedling communities leading to low densities on edges that showed less favorable conditions for arrival, establishment and initial survival. The basal area patterns were not affected by edge effects apparently by the resistance of the seedlings that have more than 4 mm diameter. Therefore, linear canopy openings caused edge effects, which determine low seedling densities on edges. However this pattern is not due to increase mortality on these edges, but probably caused by the reduction on germination and establishment. 展开更多
关键词 forest Regeneration Fragmentation Disturbance Human-Modified habitatS Secondary forestS
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Predicting Cork Oak Suitability in Maâmora Forest Using Random Forest Algorithm
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作者 Said Lahssini Hicham Lahlaoi +3 位作者 Hicham Mharzi Alaoui El Aid Hlal Martino Bagaram Quentin Ponette 《Journal of Geographic Information System》 2015年第2期202-210,共9页
Maamora is considered the most important cork-oak forest in the world with regard to surface. Therefore, anthropic pressure, including cork harvesting, grazing and soft acorn picking up by local communities, has harmf... Maamora is considered the most important cork-oak forest in the world with regard to surface. Therefore, anthropic pressure, including cork harvesting, grazing and soft acorn picking up by local communities, has harmful consequences on forest regeneration and the forest become older exceeding harvesting age. Thus, its sustainability depends on the managers’ ability to succeed cork oak plantations. This work presents an assessment approach to evaluate Quercus suber suitability to its plantation which is based on a random forest algorithm (RF). In fact, this suitability has been assessed through analyzing management data related to previous plantation success rates (SR). Then a relationship between SR and a set of environmental and social factors has been investigated using the RF. Application of the fitted model to continuous maps of all involved factors enabled establishment of suitability maps which would help managers to make more rational decisions in terms of cork oak regeneration, ensuring Maamora forest sustainability. 展开更多
关键词 CORK OAK Maamora habitat SUITABILITY RANDOM forest GIS
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Seed dispersal by Tana River mangabeys in fragmented gallery forests
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作者 Duncan M. Kimuyu Geoffrey M. Wahungu Dennis O. Otieno 《Open Journal of Ecology》 2012年第1期12-20,共9页
Data collected on a free ranging group of Tana River mangabeys (Cercocebus galeritus) indicates that this endangered primate species, which has previously been regarded as a seed predator, plays an important role in s... Data collected on a free ranging group of Tana River mangabeys (Cercocebus galeritus) indicates that this endangered primate species, which has previously been regarded as a seed predator, plays an important role in seed dispersal and do contribute to the regeneration of a highly fragmented gallery forest. We observed fruit handling behavior and the post-dispersal fate of seeds ingested by the mangabeys. The two main fruit handling behaviors observed, fruit swallowing and processing fruits in cheek pouches, positively contributed to seed disper- sal. Seed predation was not common during this study, apart from a few particular plant species such as Acacia robusta and Alangium salviifolium with non-fleshy fruits. We found a correlation between seed predation and fruit availability, respectively seasonal differential specific dispersal efficiency. The role of the mangabeys in dispersing seeds and facilitating forest regeneration is enhanced by their movement across forest patches through non-forested matrix, which contributes to the deposition of seeds and regeneration in these habitat gaps. 展开更多
关键词 Cercocebus Galeritus SEED Dispersal SEED PREDATION SEASONALITY Dispersal Efficiency Fragmentation habitat GAPS Tana RIVER forestS
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西大圈森林公园野生大型真菌多样性调查
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作者 薛春梅 唐欣欣 +3 位作者 吴薇 刘迪 石磊 翟晓旭 《佳木斯大学学报(自然科学版)》 CAS 2024年第1期177-180,共4页
为了掌握勃利县西大圈森林公园的野生大型真菌的资源现状,作者对西大圈森林公园5种生境的野生大型真菌进行了采样调查,对采集到的大型真菌进行了分类学鉴定,对野生大型真菌的物种多样性和相似度进行了统计分析。经调查公园有真菌46种,... 为了掌握勃利县西大圈森林公园的野生大型真菌的资源现状,作者对西大圈森林公园5种生境的野生大型真菌进行了采样调查,对采集到的大型真菌进行了分类学鉴定,对野生大型真菌的物种多样性和相似度进行了统计分析。经调查公园有真菌46种,其中优势种8种。西大圈森林公园的多样性指数最高的是针阔混交林生境,均匀度指数和优势度指数最高的是灌丛生境。西大圈森林公园相似度指数最高的是针阔混交林生境和灌丛生境的相似度。本研究将为掌握和分析东北地区森林公园的野生大型真菌资源有较好的借鉴意义,同时也为本地大型真菌资源开发与利用提供技术支持。 展开更多
关键词 野生大型真菌 资源调查 多样性 不同生境 西大圈森林公园
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Harvesting of forest products and implications for Afrotemperate bird communities in a montane forest of the Eastern Cape, South Africa
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作者 Jessica Leaver Johann C.Carstens Michael I.Cherry 《Forest Ecosystems》 SCIE CSCD 2019年第4期352-366,共15页
Background: Harvesting of forest products is a widespread driver of disturbance in developing nations, where policies are increasingly aimed at managing natural forests for sustainable use. There is thus need for rese... Background: Harvesting of forest products is a widespread driver of disturbance in developing nations, where policies are increasingly aimed at managing natural forests for sustainable use. There is thus need for research aimed at understanding the impact of resource use on forest habitats and concomitant effects on biodiversity.Afromontane forests in the Eastern Cape, South Africa are harvested informally for poles and medicinal bark and occur along elevational gradients of 800–1600 m above sea level. Patterns of spatial diversity and human disturbance are expected to be affected by elevation. Furthermore, species’ responses to disturbance are expected to vary depending on their level of habitat specialisation. Understanding harvest impacts on forest biodiversity thus requires disentangling the separate effects of elevation and disturbance, and considering forest-specialist and forest-generalist species separately. This study comprises two components. First, harvest activities, resultant harvestmediated habitat heterogeneity, and avifaunal species richness, composition and beta-diversity were compared across two elevational zones in a harvested forest. Second, the role of harvest-mediated habitat heterogeneity in driving patterns of avifaunal diversity were assessed, while controlling for elevation, and considering forest-specialist and forest-generalist species separately.Results: Harvest rates were higher, and activities more varied in the lower elevation zone, with significant impacts of harvesting on habitat features resulting in higher harvest-mediated habitat heterogeneity at lower elevations.Harvest-mediated increases in habitat heterogeneity positively affected forest-generalist species richness, while forest-specialist richness was negatively affected. While species composition of both groups differed across elevational zones, variation in harvest-mediated habitat heterogeneity did not fully account for this, suggesting that factors other than disturbance shape avifaunal communities along the elevation gradient. However, variation in harvest-mediated habitat heterogeneity accounted for the amount of beta-diversity attributed to species turnover in the forest-specialist assemblage, indicating that harvest disturbances affect the mechanisms driving beta-diversity of this group.Conclusion: Spatial patterns of avifaunal diversity are affected by elevation over a 300-m gradient. Harvesting results in increased habitat heterogeneity, which variably affects avifaunal communities at the forest-scale, with positive effects for forest generalists and negative effects for forest-specialists. 展开更多
关键词 Human disturbance habitat heterogeneity habitat modification BETA-DIVERSITY ELEVATION Generalist species forest-specialist species
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万宁市小海红树林生境适宜性评价及修复分析 被引量:1
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作者 薛飞 王高丹 +2 位作者 杨帆 王琰 黄毅 《生物安全学报(中英文)》 CSCD 北大核心 2024年第2期154-160,208,共8页
【目的】定量分析评估复杂环境条件与红树林分布特征之间的交互作用,探索一定区域尺度上红树林生境适宜性及适生区空间分布格局。【方法】以万宁市小海为研究区,选取水文动力、水质底质、地形高程3个大类环境变量,通过层次分析法搭建评... 【目的】定量分析评估复杂环境条件与红树林分布特征之间的交互作用,探索一定区域尺度上红树林生境适宜性及适生区空间分布格局。【方法】以万宁市小海为研究区,选取水文动力、水质底质、地形高程3个大类环境变量,通过层次分析法搭建评价结构模型,结合德尔菲法获得各指标权重,并将各环境指标经归一化处理后基于GIS技术获取小海红树林适生区的空间分布。【结果】影响小海红树林生长分布的主要环境变量为水深高程、潮位、潮差、盐度等因子;研究区港北口门附近区域红树林生境适宜性较高,面积约121.6 hm 2;西南侧及东南侧区域适宜性适中,面积约328.5 hm 2;南侧及中间部分区域适宜性较低,面积约137.2 hm 2。【结论】小海区域的气候、水质和水文动力条件均较适宜红树林存活、生长,相当一部分清退的养殖塘具备红树林种植修复的基本生态条件,但需进行生境改造,并依据生态位原理合理搭配红树物种,以期达到修复效果。 展开更多
关键词 红树林 层次分析法 生境适宜性 生态保护修复
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Raccoon Use of Den Trees and Plant Associations in Western Mesophytic Forests: Tree Attributes and Availability or Landscape Heterogeneity?
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作者 Winston P. Smith Keith M. Endres 《Natural Resources》 2012年第3期75-87,共13页
We monitored 15 radio-collared raccoons (Procyon lotor) on Davies Island in March 1987 - May 1988 to determine the extent to which individual tree attributes or spatial configuration of plant associations (habitat typ... We monitored 15 radio-collared raccoons (Procyon lotor) on Davies Island in March 1987 - May 1988 to determine the extent to which individual tree attributes or spatial configuration of plant associations (habitat types) across the landscape influenced den use. Of 1091 verified den sites, 428 were in tree cavities. Raccoon occurrence among 4 cover types differed from that expected based on the total area of each across the island and varied across all seasons for all habitat types except Cedar Wood. Preference varied among age and sex groups and across seasons with some groups showing opposite selection for the same cover type in different seasons. Species and diameter-class distributions of selected den trees differed from a random sample of trees across the landscape. Species composition of trees with cavities also differed from the species composition across the study area. American beech (Fagus grandifolia—relative abundance 8.7%) was over-represented in the sample of trees with cavities (29.4%) and trees selected as dens (65%);diameter at breast height (dbh) of beech den trees averaged 80.0 cm, whereas all beech trees averaged 71.2 cm. For all species combined, mean dbh of den trees was 78.4 cm as compared to trees with cavities (67.6 cm), or all trees (50.4 cm). The relative availability of large, cavity-prone tree species was related to previous logging practices. 展开更多
关键词 DEN USE habitat USE Landscape Heterogeneity Procyon lotor Resource AVAILABILITY Mesophytic forest
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玛卡种植对云南会泽越冬斑头雁栖息地利用和选择的影响
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作者 刘红 雷宇 +3 位作者 孟子文 张建军 陈南英 刘强 《生态学报》 CAS CSCD 北大核心 2024年第20期9221-9232,共12页
玛卡(Lepidium meyenii)作为一种滋补药材在2012年引入我国西南地区,随后种植面积不断扩大,在2018年前后因市场价格回落,其种植规模迅速萎缩。云南会泽黑颈鹤国家级自然保护区念湖片区是斑头雁(Anser indicus)的重要越冬地,也是玛卡的... 玛卡(Lepidium meyenii)作为一种滋补药材在2012年引入我国西南地区,随后种植面积不断扩大,在2018年前后因市场价格回落,其种植规模迅速萎缩。云南会泽黑颈鹤国家级自然保护区念湖片区是斑头雁(Anser indicus)的重要越冬地,也是玛卡的主要产区之一,玛卡种植面积的剧烈变化也为研究农田候鸟对农耕环境的适应性提供了契机。于2015—2020年在使用卫星跟踪技术在会泽保护区对8只越冬斑头雁进行了长时跟踪,在个体水平上比较了玛卡种植期(2015—2018年)和传统作物种植期(2019—2021年)越冬斑头雁栖息地利用和选择的差异,结果表明:(1)在两个时期,斑头雁的栖息地利用模式发生了剧烈改变。在玛卡种植期斑头雁主要利用沼泽(71.29±3.54)%,其次为耕地(18.12±2.90)%和深水水域(10.59±5.97)%,而在传统作物种植期,主要的利用类型则转变为耕地(74.44±4.84)%,其次为沼泽(12.53±6.97)%和深水水域(12.25±2.44)%。(2)对于同一只斑头雁个体,在不同越冬年份,其栖息地利用模式较稳定。A5号斑头雁在2019年和2020年越冬季均表现为对耕地利用率较高,分别为76.95%和80.41%;A6号斑头雁在2019、2020和2021年越冬时,均偏好利用耕地,利用率分别为76.52%、80.61%和75.74%。(3)在栖息地选择方面,斑头雁对9个环境因子均具有选择性。根据随机森林模型评估结果,最重要的因子均为距夜栖地距离,表明斑头雁对夜栖水环境的依赖性。在其它因子上,两个时期则表现出一定的差异性。在玛卡种植期,斑头雁栖息地选择模式中各类因子的优先顺序为夜栖地>主要觅食地>回避类栖息地>人为干扰因子;在传统作物种植期则为夜栖地>回避类栖息地>人为干扰因子>主要觅食地。综合来看,玛卡种植会对斑头雁产生不利影响,不仅会直接减少斑头雁的优质栖息地面积,而且会直接改变斑头雁栖息地利用和选择模式。建议在保护区内或周边区域实施大规模农业耕种模式调整时,应充分考虑农田鸟类的栖息地需求,进行科学管理。 展开更多
关键词 斑头雁 玛卡 随机森林 栖息地选择 栖息地利用
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城市生态公益林再野化的草本植物及其生境热点快速监测识别技术 被引量:2
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作者 杨博 孙彦伟 +4 位作者 郑思俊 朱义 陈雪初 黄静蕾 敖东力 《中国城市林业》 2024年第2期56-63,共8页
受乔木遮挡影响,难以采用遥感技术监测城市生态公益林内现状草本植被,而人工监测费时费力。为攻关此难题,以生境热点监测识别为突破口,开发一种适用于中观尺度城市生态公益林的快速监测识别技术体系,通过分析高分辨率的遥感影像,快速识... 受乔木遮挡影响,难以采用遥感技术监测城市生态公益林内现状草本植被,而人工监测费时费力。为攻关此难题,以生境热点监测识别为突破口,开发一种适用于中观尺度城市生态公益林的快速监测识别技术体系,通过分析高分辨率的遥感影像,快速识别原生草本植物多样性较高的空间范围,对此类空间开展重点法抽样,经对上海市金山区农林水乡生态公益林实地验证,该方法效果较好,具体表现为:单独使用一种抽样法时,重点法的探测效率更高,草本原生种探测效率约为79%,优于系统法+路径法组合使用(72%);两种方法组合使用时,重点法能够将物种探测效率提高16%~24%,其中系统法+重点法的草本原生种探测效率约为88%,路径法+重点法的草本原生种探测效率约为96%。研究结果说明生境热点内的草本原生种数量较多,生境热点识别技术有效;明确生境热点的空间范围,能够提高生物多样性监测效率、降低监测人力和时间成本,为生态修复工程规划、设计、施工和评估提供重要的空间信息;同时,利用人工智能技术开展公众参与监测研究,降低了监测成本,能够保障监测识别的准确性和可持续性。因此,该技术能够为城市生态公益林再野化提供有力的技术支持,具有广阔的应用前景。 展开更多
关键词 城市生态公益林 再野化 草本植物 生境热点 快速监测识别技术
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林窗对黄檗幼树空间分布及生长发育的影响
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作者 刘昌 路琦 +4 位作者 汪生财 陈梦缘 邢韶华 王清春 杨军 《北京林业大学学报》 CAS CSCD 北大核心 2024年第2期9-17,共9页
【目的】林窗增加了林分空间结构的复杂性和林下生境的异质性,对林下幼树的更新具有重要影响。黄檗是我国国家重点保护野生植物,研究黄檗幼树的生长状况、空间分布与林窗空间结构的关系,有助于了解其对林下生境的适应性,对促进黄檗种群... 【目的】林窗增加了林分空间结构的复杂性和林下生境的异质性,对林下幼树的更新具有重要影响。黄檗是我国国家重点保护野生植物,研究黄檗幼树的生长状况、空间分布与林窗空间结构的关系,有助于了解其对林下生境的适应性,对促进黄檗种群的更新具有重要意义。【方法】本文以2014年在北京百花山自然保护区内林下栽种的黄檗幼树为研究对象,于2021年对黄檗的生长及存活状况进行了调查,并使用背包式激光雷达获取了样地的林窗空间结构数据。采用空间点格局、生境关联性检验和方差分析等方法研究了林窗对黄檗幼树空间分布及生长状况的影响。【结果】(1)自然生长条件下,7年后黄檗幼树存活率为19.25%,在排除扩散限制后,存活黄檗幼树的空间分布表现为聚集分布。(2)林窗空间结构是黄檗幼树空间分布格局形成的重要原因,黄檗幼树分布与林窗边缘呈显著正关联,而与林冠区呈显著负关联。(3)黄檗幼树的基径在林窗边缘显著高于林冠区和林窗中心(P<0.01),在林冠区与林窗中心之间没有显著差异;黄檗幼树的冠幅和树高则呈现显著的梯度变化(P<0.05),即林窗边缘>林冠区>林窗中心。【结论】研究表明林窗对黄檗幼树的空间分布格局和生长状况具有重要的影响。林窗边缘的生境条件更有利于黄檗幼树的存活和生长,而林窗中心和林冠区则会对黄檗幼树的生长发育产生一定的抑制作用。 展开更多
关键词 激光雷达 空间点格局 物种-生境关联 林窗 幼树
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珠三角彩叶林美学文化与功能评价指标体系构建
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作者 王淳 郝泽周 +7 位作者 孙冰 李乐 高丙涛 曾伟 陈勇 万利鑫 柯欢 裴男才 《北京大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第2期357-364,共8页
针对珠三角城市群中广州、深圳、佛山等地及周边地区常见的彩叶树种美学文化功能评价中的关键问题,在文献梳理和理论实践的基础上,运用专家评估法和层次分析原理建立综合指标法,构建包括3个准则层(B1~3)、9个次准则层(C1~9)和27个指标层... 针对珠三角城市群中广州、深圳、佛山等地及周边地区常见的彩叶树种美学文化功能评价中的关键问题,在文献梳理和理论实践的基础上,运用专家评估法和层次分析原理建立综合指标法,构建包括3个准则层(B1~3)、9个次准则层(C1~9)和27个指标层(D1~27)的评价指标体系,以期有效地评价珠三角彩叶林的美学与文化功能,明确森林城市群生态系统文化服务保护与开发的重点,提升彩色林相营建技术与美丽湾区建设的匹配性与实用性,拓展城市林业和人居环境学科理论的内涵与应用。 展开更多
关键词 森林生态系统服务 城市林业 森林城市群 人居环境 可持续发展
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高节竹表型可塑性对沿海沙地生境的响应
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作者 张迎辉 蔡星 +5 位作者 肖晓梅 何天友 李云鸽 荣俊冬 陈礼光 郑郁善 《世界竹藤通讯》 2024年第5期38-46,共9页
探究高节竹(Phyllostachys prominens)对沿海沙地困难立地生境的适应性策略,为沿海沙地竹类植物的引种和培育提供理论依据。以原产地山地红壤和引种地沿海沙地2种生境条件下的高节竹为研究对象,对其分株、竹枝、叶片、竹鞭等构件形态特... 探究高节竹(Phyllostachys prominens)对沿海沙地困难立地生境的适应性策略,为沿海沙地竹类植物的引种和培育提供理论依据。以原产地山地红壤和引种地沿海沙地2种生境条件下的高节竹为研究对象,对其分株、竹枝、叶片、竹鞭等构件形态特征指标进行测定,探讨高节竹表型可塑性对沿海沙地生境的响应。结果表明,与山地红壤生境相比,沿海沙地生境高节竹的株高、胸径、总节数和分枝节数分别显著降低26.15%、35.58%、26.68%和18.90%(P<0.05);Ⅰ、Ⅱ、Ⅲ级分枝角度分别显著增加17.48%、19.40%、27.69%,而分枝长度和分枝数量显著降低(P<0.05);叶长、叶面积、叶形指数和比叶面积分别显著降低20.21%、23.79%、23.52%和8.65%,叶片厚度显著增加14.41%(P<0.05);平均鞭径、平均鞭节长和生物量分别显著降低24.2%、33.54%、19.03%,总鞭长、鞭节密度和总芽数分别显著增加19.92%、37.34%、42.61%(P<0.05);土壤pH值、水解氮和全氮含量是影响沿海沙地高节竹表型可塑性的关键因素。高节竹通过分株构件形态、叶片功能性状和地下茎形态等多方面的形态可塑性变化以适应沿海沙地困难立地生境。 展开更多
关键词 高节竹 表型性状 沿海沙地 生境 防护林
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