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Preliminary Study on Forest Fire Prevention and Extinguishing in Townships in the Southern Mountainous Areas of Zhejiang Province:A Case Study of Lishui
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作者 Dalin WANG Ming LUO +2 位作者 Xiaobing YANG Siwei ZHENG Jian DENG 《Meteorological and Environmental Research》 2023年第6期53-57,共5页
Forest fires seriously threaten forestry resources and the life and property safety of people in mountainous areas of Lishui City. In this paper, a fire prevention concept with refined forecast and early warning of fo... Forest fires seriously threaten forestry resources and the life and property safety of people in mountainous areas of Lishui City. In this paper, a fire prevention concept with refined forecast and early warning of forest fire danger weather ratings in townships as the starting point, satellite real-time observation of fire spots, monitoring of the Internet of Things and other high-tech products as an implementation means, and strengthening forest fire prevention equipment and personnel in townships as a guarantee was established. The command system for rapid emergency response by cities, counties and townships should be improved. During the forest fire prevention period, fire sources should be strictly controlled, and the basic principles of forest fire fighting in townships should be implemented into the actual fire prevention and fire fighting work to eliminate forest fires in time at the initial stage and before the disaster. 展开更多
关键词 Mountainous areas of southern Zhejiang Townships forest fire danger
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Fine-scale activity patterns of large-and medium-sized mammals in a deciduous broadleaf forest in the Qinling Mountains,China 被引量:1
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作者 Yuke Zhang Xiangbo He +3 位作者 Xuehua Liu Melissa Songer Haishan Dang Quanfa Zhang 《Journal of Forestry Research》 SCIE CAS CSCD 2021年第6期2709-2717,共9页
The composition of animal species and interactions among them are widely known to shape ecological communities and fine-scale(e.g.,<1 km)monitoring of animal communities is essential for understanding the relations... The composition of animal species and interactions among them are widely known to shape ecological communities and fine-scale(e.g.,<1 km)monitoring of animal communities is essential for understanding the relationships among animals and plants.Although the co-existence of large-and medium-sized species has been studied across different scales,research on fine-scale interactions of herbivores in deciduous broadleaf forests is limited.Camera trapping of large-and medium-sized mammals was carried out over a 1 year period within a 25 ha deciduous broadleaf forest dynamics plot in the Qinling Mountains,China.Fourteen species of large-and medium-sized mammals,including six carnivores,six ungulates,one primate and one rodent species were found.Kernel density estimations were used to analyse the diel or 24 h activity patterns of all species with more than 40 independent detections and general linear models were developed to explore the spatial relationships among the species.The combination of overlapping diel activity patterns and spatial associations showed obvious niche separation among six species:giant panda(Ailuropoda melanoleuca David),takin(Budorcas taxicolor Hodgson),Reeves’s muntjac(Muntiacus reevesi Ogilby),tufted deer(Elaphodus cephalophus Milne-Edwards),Chinese serow(Capricornis milneedwardsii David)and wild boar(Sus scrofa Linnaeus).Long-term fine-scale monitoring is useful for providing information about the co-existence of species and their interactions.The results demonstrate the importance for fine-scale monitoring of animals and plants for improving understanding of species interactions and community dynamics. 展开更多
关键词 Large-and medium-sized mammals Fine-scale interaction Camera trapping Spatiotemporal patterns forest dynamics plots qinling mountains
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Nitrous oxide emissions from three temperate forest types in the Qinling Mountains,China
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作者 Wei Xue Changhui Peng +5 位作者 Huai Chen Hui Wang Qiuan Zhu Yanzheng Yang Junjun Zhang Wanqin Yang 《Journal of Forestry Research》 SCIE CAS CSCD 2019年第4期1417-1427,共11页
To understand soil N2O fluxes from temperate forests in a climate-sensitive transitional zone,N2O emissions from three temperate forest types(Pinus tabulaeformis,PTT;Pinus armandii,PAT;and Quercus aliena var.acuteserr... To understand soil N2O fluxes from temperate forests in a climate-sensitive transitional zone,N2O emissions from three temperate forest types(Pinus tabulaeformis,PTT;Pinus armandii,PAT;and Quercus aliena var.acuteserrata,QAT)were monitored using the static closed-chamber method from June 2013 to May 2015 in the Huoditang Forest region of the Qinling Mountains,China.The results showed that these three forest types acted as N2O sources,releasing a mean combined level of 1.35±0.56 kg N2O ha^-1 a^-1,ranging from0.98±0.37 kg N2O ha^-1 a^-1 in PAT to 1.67±0.41 kg N2O ha^-1 a^-1 in QAT.N2O emission fluctuated seasonally,with highest levels during the summer for all three forest types.N2O flux had a significantly positive correlation with soil temperature at a depth of 5 cm or in the water-filled pore space,where the correlation was stronger for temperature than for the water-filled pore space.N2O flux was positively correlated with available soil nitrogen in QAT and PAT.Our results indicate that N2O flux is mainly controlled by soil temperature in the temperate forest in the Qinling Mountains. 展开更多
关键词 forest types GREENHOUSE gases N2O FLUXES qinling mountains Soil temperature
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Characteristics of rock fragments in different forest stony soil and its relationship with macropore characteristics in mountain area, northern China 被引量:5
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作者 MENG Chen NIU Jian-zhi +3 位作者 YIN Zheng-cong LUO Zi-teng LIN Xing-na JIA Jing-wei 《Journal of Mountain Science》 SCIE CSCD 2018年第3期519-531,共13页
Rock fragments have major effect on soil macropores and water movement. However, the characteristics of rock fragments and their relationship with macropore characteristics remain elusive in forest stony soils in nort... Rock fragments have major effect on soil macropores and water movement. However, the characteristics of rock fragments and their relationship with macropore characteristics remain elusive in forest stony soils in northern mountainous area of China. The objectives of this study are to(1) use Industrial Computed Tomography(CT) scanning to quantitatively analyze rock fragment characteristics in intact soil columns in different forest lands and(2) identify the relationship between characteristics of rock fragments and that of the macropores. Intact soil columns that were 100 mm in diameter and 300 mm long were randomly taken from six local forest stony soils in Wuzuolou Forest Station in Miyun, Beijing. Industrial CT was used to scan all soil column samples, and then the scanned images were utilized to obtain the three-dimensional(3 D) images of rock fragments and macropore structures. Next, theparameters of the rock fragments and macropore structure were measured, including the volume, diameter, surface area, and number of rock fragments, as well as the volume, diameter, surface area, length, angle, tortuosity and number of macropores. The results showed that no significant difference was found in soil rock fragments content in the 10-30 cm layer between mixed forest and pure forest, but in the 0-10 cm soil layer, the rock fragments in mixed forest were significantly less than in pure forest. The number density of macropores has significant negative correlation with the number of rock fragments in the 0-10 cm soil layer, whereas this correlation is not significant in 10-20 cm and 20-30 cm soil layers. The volume density of macropore was not correlated with the volume density of rock fragments, and there is no correlation between the density of macropore surface area and the density of rock fragment surface area. Industrial CT scanning combined with image processing technology canprovide a better way to explore 3 D distribution of rock fragments in soil. The content of rock fragments in soil is mainly determined by parent rocks. The surface soil(0-10 cm) of forest contains fewer rock fragments and more macropores, which may be caused by bioturbation, root systems, gravitational settling and faunal undermining. 展开更多
关键词 土壤岩石 特征和 森林 中国 体积密度 山区 碎裂 扫描图象
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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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Ecological Function Value of Tropical Forests in the Central Mountainous Areas of Hainan Island
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作者 Jing GAO Zuguang ZHOU 《Asian Agricultural Research》 2013年第11期103-105,108,共4页
The integrated value of the ecological function of tropical forests in the central mountainous areas of Hainan Island was 33.064 8 billion yuan/a in 2010(soil improvement,soil consolidation,soil nutrient maintenance,w... The integrated value of the ecological function of tropical forests in the central mountainous areas of Hainan Island was 33.064 8 billion yuan/a in 2010(soil improvement,soil consolidation,soil nutrient maintenance,water storage and moisture regulation,water purification,carbon sequestration,oxygen releasing,air purification,biodiversity conservation,eco-tourism),equivalent to 16.1%of GDP in Hainan Province this year(205.212 billion yuan).The tropical forests in the central mountainous areas of Hainan Island make great contribution to Hainan Island's ecology,and play an important role in maintaining the stability of the ecological environment in Hainan Island.Through the understanding of major ecological function value of tropical forests,it is necessary to make people cherish the tropical forests in the central ecological function conservation areas of Hainan Province,and spontaneously throw themselves into the ecological environment protection and construction,to promote the rapid and sustainable development of construction in Hainan Province as an international tourism island. 展开更多
关键词 CENTRAL mountainous areas TROPICAL forestS Ecologi
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Spatial patterns of the main trees in a plant micro-reserve constructed in the 2022 Beijing Winter Olympics mountainous competition zone
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作者 WANG Jian-yong ZHANG Zhi-xiang 《Journal of Mountain Science》 SCIE CSCD 2023年第8期2228-2241,共14页
Several plant micro-reserves were established to preserve the vegetation in local mountain areas during the construction of the Yanqing competition zone of the 2022 Beijing Winter Olympics.The spatial patterns of the ... Several plant micro-reserves were established to preserve the vegetation in local mountain areas during the construction of the Yanqing competition zone of the 2022 Beijing Winter Olympics.The spatial patterns of the main species in one of the micro-reserves and the factors affecting these patterns were characterized in this study.The distribution of arbor species was found to be mostly aggregated,especially at fine scales(<5 m).Minor species were found to be more aggregated than the major species in each forest layer.The spatial patterns were found to be affected by habitat heterogeneity,intraspecific relationships,interspecific competition,and seed dispersal limitation.Habitat heterogeneity was found to affect large-scale spatial patterns,and its effects were observed throughout population development.Interspecific competition is another factor affecting the distribution of the species,and its effects were stronger during the later stages of population development.Habitat heterogeneity was found to affect competition among species and is key for species coexistence.Both these processes are affected by the seed dispersal limitation,and intraspecific relationships are a legacy of seed dispersal.The point patterns can be used as a tool for the initial assessment of the status of communities within micro-reserves.The consideration of these relationships in the development,management,and formulation of policies for micro-reserves in mountainous areas will facilitate the achievement of conservation goals.The careful consideration of habitat conditions when selecting sites for micro-reserves establishment can promote species conservation. 展开更多
关键词 Spatial patterns Point patterns Microreserve Juglans mandshurica forest Beijing mountainous area
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Recreational potential as an indicator of accessibility control in protected mountain forest areas 被引量:4
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作者 Tomasz DUDEK 《Journal of Mountain Science》 SCIE CSCD 2017年第7期1419-1427,共9页
The article presents research findings related to recreational use of forests located in protected mountainous areas with forestage of over 80%. The study was designed to identify recreational potential of the Carpath... The article presents research findings related to recreational use of forests located in protected mountainous areas with forestage of over 80%. The study was designed to identify recreational potential of the Carpathian national parks(Bieszczady National Park, Babia Góra National Park, Gorce National Park and Magura National Park; southern Poland) and to compare these findings with the actual number of visitors. The information received on the recreational potential of parks is important from the point of view of protection of natural resources and the financial situation of the parks. The calculated ratio may be an effective tool of management for park administration, that allows to reconcile statutory social and protective functions of national parks. The study determined the recreational potential of the forests with the use of recreational valorisation method designed for areas with varied terrain, and the evaluated factors included the stands of trees with their habitat and land relief. The permissible number of national park visitors, expressed as manhour/ha/year ranges from 19.31 in Bieszczady National Park(BG: 19o 35' E, 49o 35' N) to 32.06 in in Bieszczady National Park(B: 22o 40' E, 49o 10' N). In 3 out of 4 investigated parks, Magura National Park(M: 21°25' E, 49o 30' N), Gorce National Park(G: 20o10' E, 49o 35' N), B) recreation carrying capacity was not exceeded, whether or not the strictly protected area is taken into account. Only in BG was the recreation carrying capacity exceeded by nearly 24%,or by 85% if the strictly protected area isexcluded from tourism-related exploitation. The presented procedure for monitoring access to mountain forests in national parks, from the viewpoint of natural resources conservation, can be applied in other mountainous areas covered with forests and exposed to tourist and recreational traffic,and in forests facing particular risk of recreational damage, e.g. in urban and suburban forests growing in areas with varied orography. 展开更多
关键词 森林游憩 保护区 可达性 自然资源保护 国家公园 控制 林区 喀尔巴阡山脉
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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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Depth Distribution Pattern of Soil Organic Carbon in Forest from Taowan Basin of Funiu Mountain Area
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作者 Xifeng NING Lina SONG Yaowu TIAN 《Asian Agricultural Research》 2019年第6期20-24,共5页
[Objectives]By testing applicability of SOC depth distribution model in geographical and climatic conditions of Funiu Mountain area,SOC depth distribution model in the region was established and applied. The construct... [Objectives]By testing applicability of SOC depth distribution model in geographical and climatic conditions of Funiu Mountain area,SOC depth distribution model in the region was established and applied. The constructed model was used to estimate SOC mass density in other regions,thereby obtaining SOC abundance distribution chart at different depths.[Methods]165 soil sampling sites were selected from Quercus variabilis forest,Pinus tabulaeformis forest,mixed forest,and shrub forest in Taowan basin of Funiu Mountain area,to determine SOC content at different depths,study SOC depth distribution pattern of forest in Taowan basin of Funiu Mountain area,and assess SOC reserve at different depths.[Results]Average SOC density of Q. variabilis forest,P. tabulaeformis forest,mixed forest,and shrub forest at the depth of 0-20 cm was 7. 92,8. 42,8. 14 and 9. 67 kg/m^2,and there was significant difference in SOC density between shrub forest and Q. variabilis forest,P. tabulaeformis forest,mixed forest( P < 0. 05),and SOC density of four kinds of vegetation all abruptly declined with soil depth increased. At the depth of 0-20 cm,correlation between SOC density and vegetation type,canopy density,clay content and sand content was significant,and the correlation with altitude was insignificant. When carbon density at the depth of 0-100 cm was used to describe regional SOC reserve,the estimated value was lower. The established space model could predict SOC density of forest.[Conclusions]The estimation of deep-layer SOC by the established model needed further consideration,and estimation method for special areas needed to be further demonstrated. 展开更多
关键词 Funiu MOUNTAin area Taowan BASin forest Soil ORGANIC carbon DEPTH distribution
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The Research of Forest Soil Organic Carbon Accumulation in Dabie Mountain
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作者 YANG Shu-yun,YANG Ke-feng,ZHANG Xin-tong,WANG Jun Anhui Agricultural University,Hefei 230036,China 《Meteorological and Environmental Research》 CAS 2011年第3期39-42,共4页
In subtropical to warm temperate transitional zone of the Dabie Mountains hinterland forest topsoil as the research object this text,through the different levels of soil bulk density,organic carbon content of the dete... In subtropical to warm temperate transitional zone of the Dabie Mountains hinterland forest topsoil as the research object this text,through the different levels of soil bulk density,organic carbon content of the determination of analytical studies in the area of forest surface soil organic carbon density.Because of the ecological role of small environment,the study area within the soil bulk density increased with depth,surface soil porosity,and bulk density from top to bottom in 0.8.All measuring points are the 0-10 cm surface layer soil organic carbon content are highest,content between 67.232-61.940 g/kg,this,because the forest soil organic carbon important source withers and falls in the vegetation stack and rotten.Different measuring point organic carbon along with depth change characteristic slightly different,low elevation the measuring point soil organic carbon content increases the monotonous drop along with the depth,the elevation is high,the measuring point slightly has in the 30-40 cm depth content increases.The comprehensive bulk specific gravity factor computation,the 0-40 cm soil organic carbon total content slightly has along with altitude above sea level’s rise increases,each square meter organic carbon content between 16 560.5-18 354.6 g,studies the region 0-40 cm soil organic carbon content mean value by 3 measuring points mean value achievement,then this region 0-40 cm soil organic carbon density approximately 174.3 t/hm2;Refers to the related research between the surface layer and the 0-100 cm soil layer organic carbon content relational reckoning,studies the region 0-100 cm soil organic carbon density to be possible to reach 233.9 t/hm2,it indicated that the Dabie Mountain area forest soil system has the giant organic carbon capacity. 展开更多
关键词 Dabie Mountain area forest soil Organic carbon density China
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Assessing the invasion risk of botanical garden's exotic threatened collections to adjacent mountain forests: A case study of Cibodas Botanical Garden
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作者 JUNAEDI Decky Indrawan PUTRI Dwinda Mariska KURNIAWAN Vandra 《Journal of Mountain Science》 SCIE CSCD 2021年第7期1847-1855,共9页
A primary objective of botanical gardens is to conserve threatened plant species from different regions and countries.However,such ex-situ conservation practices for exotic plant species may pose a significant plant i... A primary objective of botanical gardens is to conserve threatened plant species from different regions and countries.However,such ex-situ conservation practices for exotic plant species may pose a significant plant invasion risks.In this study,we predict the naturalization probability of exotic threatened plant species of Cibodas Botanical Garden(CBG) collections based on leaf trait(specific leaf area,SLA) or as a function of invasion risk assessment scoring system(Tropical Weed Risk Assessment Protocol,TWRAP).We found that SLA and TWRAP were positively correlated with naturalization probability.The TWRAP model produced higher predictive probabilities with larger uncertainty compared to SLA model.Parmentiera cereifera and Burretiodendron hsienmu are two species that have highest naturalization probability based on SLA model.Chamaedorea oblongata has the highest naturalization probability based on TWRAP model.From practical and management point of view,we recommend the simultaneous use of SLA-based and TWRAP-based invasive species risk assessment to estimate the naturalization risk of exotic threatened collections of botanical gardens to adjacent mountain forests.Finally,given the important conservation value of threatened exotic collection of botanical garden,we need to be aware with the invasion risks of these species.The threatened condition of a plant species is not only caused by its natural characteristics but also may be caused(in fact mostly confounding with) by external disturbance either natural catastrophic or human related activities.Thus,a threatened species may not necessarily a noninvasive species outside their natural distribution ranges. 展开更多
关键词 Leaf trait Specific leaf area invasion ecology Tropical mountain forest Risk assessment Scoring assessment Cibodas Botanic Gardens
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Similarity between seed rain and neighbouring mature tree communities in an old-growth temperate forest 被引量:2
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作者 Yunyun Wang Jalene M.La.Montagne +4 位作者 Fei Lin Zuoqiang Yuan Ji Ye Xugao Wang Zhanqing Hao 《Journal of Forestry Research》 SCIE CAS CSCD 2020年第6期2435-2444,共10页
Seed distribution and deposition patterns around parent trees are strongly aff ected by functional traits and therefore infl uence the development of plant communities.To assess the limitations of seed dispersal and t... Seed distribution and deposition patterns around parent trees are strongly aff ected by functional traits and therefore infl uence the development of plant communities.To assess the limitations of seed dispersal and the extent to which diaspore and neighbouring parental traits explain seed rain,we used a 9-year seed data set based on 150 seed traps in a 25-ha area of a temperate forest in the Changbai Mountain.Among 480,598 seeds belonging to 12 families,17 genera,and 26 species were identifi ed,only 54%of the species with mature trees in the community were represented in seeds collected over the 9 years,indicating a limitation in seed dispersal.Understory species were most limited;overstory species were least limited.Species with wind-dispersed seed had the least limitation,while the lowest similarity in species richness was for animal-dispersed species followed by gravity-dispersed species;fl eshy-fruited species had stronger dispersal limitations than dry-fruited species.Generalized linear mixed models showed that relative basal area had a signifi cant positive eff ect on seed abundance in traps,while the contribution of diaspore traits was low for nearly all groups.These results suggest that tree traits had the strongest contribution to seed dispersal and deposition for all functional groups examined here.These fi ndings strengthen the knowledge that tree traits are key in explaining seed deposition patterns,at least at the primary dispersal stage.This improved knowledge of sources of seeds that are dispersed could facilitate greater understanding of seedling and community dynamics in temperate forests. 展开更多
关键词 Seed rain Dispersal mechanisms Tree traits Basal area Changbai mountain Temperate forest
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基于InVEST模型的甘肃省祁连山林区乔木林碳储量时空变化研究 被引量:1
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作者 赵方圆 王琼芳 +2 位作者 张华堂 陈智平 张璐 《西北林学院学报》 CSCD 北大核心 2023年第4期233-240,共8页
以祁连山林区乔木林为研究对象,基于甘肃省林地更新数据和中国土地覆盖及地形数据,运用InVEST模型估算和分析祁连山林区乔木林的碳储量时空变化特征。结果表明,1)研究区乔木林碳储量的分布呈现北部片状—中部点状片状—南部线状的分布... 以祁连山林区乔木林为研究对象,基于甘肃省林地更新数据和中国土地覆盖及地形数据,运用InVEST模型估算和分析祁连山林区乔木林的碳储量时空变化特征。结果表明,1)研究区乔木林碳储量的分布呈现北部片状—中部点状片状—南部线状的分布特征。2)2016-2019年研究区乔木林碳储量增长了258.91万t,年均碳汇量86.30万t。3)2016、2019年云杉的碳储量占比最大,平均占比88.82%,且以最具未来碳汇潜力的中龄林和近熟林增长为主,主要分布在海拔2500~3500 m、坡度10°~40°的阴坡和半阴坡及半阳坡。4)2016-2019年,牧草地、耕地、未利用地、建设用地向林地转移1219.22 hm^(2),呈现牧草、耕地、未利用地、建设用地向林地回转的趋势。研究结果一定程度上反映了研究区森林碳汇功能向良性转变,表明了退耕还林、人工造林等生态治理工程的有效性。 展开更多
关键词 inVEST模型 祁连山林区 碳储量
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No treeline shift despite climate change over the last 70 years
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作者 Mirela Beloiu Dimitris Poursanidis +6 位作者 Antonis Tsakirakis Nektarios Chrysoulakis Samuel Hoffmann Petros Lymberakis Antonis Barnias David Kienle Carl Beierkuhnlein 《Forest Ecosystems》 SCIE CSCD 2022年第1期13-22,共10页
Background:The recent rise in temperature and shifting precipitation regimes threaten ecosystems around the globe to different degrees.Treelines are expected to respond to climate warming by shifting to higher elevati... Background:The recent rise in temperature and shifting precipitation regimes threaten ecosystems around the globe to different degrees.Treelines are expected to respond to climate warming by shifting to higher elevations,but it is unclear whether they can track temperature changes.Here,we integrated high-resolution aerial imagery with local climatic and topographic characteristics to study the treeline dynamic from 1945 to 2015 on the semiarid Mediterranean island of Crete,Greece.Results:During the study period,the mean annual temperature at the treeline increased by 0.81℃,while the average precipitation decreased by 170 mm.The treeline is characterized by a diffuse form,with trees growing on steep limestone slopes(>50°)and shallow soils.Moreover,the treeline elevation decreases with increasing distance from the coast and with aspect(south>north).Yet,we found no shift in the treeline over the past 70 years,despite an increase in temperature in all four study sites.However,the treeline elevation correlated strongly with topographic exposure to wind(R^(2)=0.74,p<0.001).Therefore,the temporal lag in treeline response to warming could be explained by a combination of topographic and microclimatic factors,such as the absence of a shelter effect and a decrease in moisture.Conclusion:Although there was no treeline shift over the last 70 years,climate change has already started shifting the treeline altitudinal optimum.Consequently,the lack of climate-mediated migration at the treeline should raise concerns about the threats posed by warming,such as drought damages,and wildfire,especially in the Mediterranean region.Therefore,conservation management should discuss options and needs to support adaptive management. 展开更多
关键词 Aerial imagery Protected area Continental island Mediterranean region High mountains Temperature Precipitation Climate change forest dynamics
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Landslide susceptibility assessment in Western Henan Province based on a comparison of conventional and ensemble machine learning 被引量:1
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作者 Wen-geng Cao Yu Fu +4 位作者 Qiu-yao Dong Hai-gang Wang Yu Ren Ze-yan Li Yue-ying Du 《China Geology》 CAS CSCD 2023年第3期409-419,共11页
Landslide is a serious natural disaster next only to earthquake and flood,which will cause a great threat to people’s lives and property safety.The traditional research of landslide disaster based on experience-drive... Landslide is a serious natural disaster next only to earthquake and flood,which will cause a great threat to people’s lives and property safety.The traditional research of landslide disaster based on experience-driven or statistical model and its assessment results are subjective,difficult to quantify,and no pertinence.As a new research method for landslide susceptibility assessment,machine learning can greatly improve the landslide susceptibility model’s accuracy by constructing statistical models.Taking Western Henan for example,the study selected 16 landslide influencing factors such as topography,geological environment,hydrological conditions,and human activities,and 11 landslide factors with the most significant influence on the landslide were selected by the recursive feature elimination(RFE)method.Five machine learning methods[Support Vector Machines(SVM),Logistic Regression(LR),Random Forest(RF),Extreme Gradient Boosting(XGBoost),and Linear Discriminant Analysis(LDA)]were used to construct the spatial distribution model of landslide susceptibility.The models were evaluated by the receiver operating characteristic curve and statistical index.After analysis and comparison,the XGBoost model(AUC 0.8759)performed the best and was suitable for dealing with regression problems.The model had a high adaptability to landslide data.According to the landslide susceptibility map of the five models,the overall distribution can be observed.The extremely high and high susceptibility areas are distributed in the Funiu Mountain range in the southwest,the Xiaoshan Mountain range in the west,and the Yellow River Basin in the north.These areas have large terrain fluctuations,complicated geological structural environments and frequent human engineering activities.The extremely high and highly prone areas were 12043.3 km^(2)and 3087.45 km^(2),accounting for 47.61%and 12.20%of the total area of the study area,respectively.Our study reflects the distribution of landslide susceptibility in western Henan Province,which provides a scientific basis for regional disaster warning,prediction,and resource protection.The study has important practical significance for subsequent landslide disaster management. 展开更多
关键词 Landslide susceptibility model Risk assessment Machine learning Support vector machines Logistic regression Random forest Extreme gradient boosting Linear discriminant analysis Ensemble modeling Factor analysis Geological disaster survey engineering Middle mountain area Yellow River Basin
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基于“两山”理论的秦岭北麓乡村空间营建策略研究
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作者 屈雯 李倩 +3 位作者 雷振东 马琰 吴雷 郄海潮 《西安建筑科技大学学报(自然科学版)》 北大核心 2024年第3期374-381,共8页
空间营建是秦岭北麓乡村地区“两山”实践的重要保障.研究提出在乡村“资源-资产-资本”的转化过程中,应构建“两环节、三层次、多主体”的“两山”转化空间营建路径:以生态基础培育和多元增值开发为两大空间营建环节,构建“区域→单元... 空间营建是秦岭北麓乡村地区“两山”实践的重要保障.研究提出在乡村“资源-资产-资本”的转化过程中,应构建“两环节、三层次、多主体”的“两山”转化空间营建路径:以生态基础培育和多元增值开发为两大空间营建环节,构建“区域→单元→地块”三层次营建体系,建立多主体参与共赢的营建机制.研究以西安鄠邑区为例,梳理其在大都市圈发展背景下“两山”转化的乡村空间营建问题,提出“要素统筹、生境修复、产居转型、有序共建”四方面空间营建策略,形成地域适宜性的绿色共建模式,以期为地区乡村振兴和高质量建设提供借鉴. 展开更多
关键词 “两山”理论 秦岭北麓 乡村地区 空间营建
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毛竹扩张对幕阜山区森林土壤碳氮磷含量及生态化学计量特征的影响
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作者 王晓荣 胡兴宜 +5 位作者 龚苗 辜忠春 戴薛 夏少丹 刘清平 牛红玉 《西南林业大学学报(自然科学)》 CAS 北大核心 2024年第2期77-85,共9页
以幕阜山区同一片毛竹林向两侧杉木林和阔叶林扩张形成的连续生态界面为研究对象,分析不同林型土壤有机碳(SOC)、全氮(TN)、全磷(TP)、硝态氮(NO_(3)^(−)−N)、铵态氮(NH_(4)^(+)−N)含量及其生态化学计量比,探讨毛竹不同扩张模式对森林... 以幕阜山区同一片毛竹林向两侧杉木林和阔叶林扩张形成的连续生态界面为研究对象,分析不同林型土壤有机碳(SOC)、全氮(TN)、全磷(TP)、硝态氮(NO_(3)^(−)−N)、铵态氮(NH_(4)^(+)−N)含量及其生态化学计量比,探讨毛竹不同扩张模式对森林土壤碳(C)、氮(N)、磷(P)的影响。结果表明:在2种扩张模式下,随土壤层次的增加,除NO_(3)^(−)−N呈不规律变化外,SOC、TN、TP、NH_(4)^(+)−N含量均呈逐渐降低趋势。在毛竹向杉木林扩张过程中,杉木林、竹杉混交林、毛竹林同一土层SOC、TN、TP含量均无显著差异;在毛竹向阔叶林扩张过程中,毛竹林0~10 cm土层SOC和TN含量较阔叶林和竹阔混交林分别降低了27.71%、30.45%和36.67%、31.11%,而在10~20 cm和20~30 cm土层则无显著差异;毛竹扩张对杉木林和阔叶林各土层TP含量无显著影响;毛竹向杉木林扩张增加了0~10 cm和20~30 cm土层NH_(4)^(+)−N含量,毛竹向阔叶林扩张增加了10~20 cm土层NH_(4)^(+)−N含量及20~30 cm土层NO_(3)^(−)−N含量;毛竹向杉木林扩张对土壤C/N、C/P、N/P无显著影响,毛竹向阔叶林扩张导致0~10 cm土层N/P明显降低、10~20 cm土层C/N显著增加。综上,毛竹向杉木林扩张对土壤SOC、TN、TP影响不显著,但提升了表层和深层土壤NH_(4)^(+)−N含量,毛竹向阔叶林扩张造成表层土壤SOC、TN含量显著降低,并导致中层土壤NH_(4)^(+)−N含量和深层土壤NO_(3)^(−)−N含量明显增加。 展开更多
关键词 毛竹扩张 杉木林 阔叶林 土壤养分 生态化学计量 幕阜山区
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辽东山区5种林分土壤颗粒分形特征与土壤性质
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作者 邓继峰 万龙燕 +4 位作者 侯瑞萍 李景浩 武斌 韩明 石小亮 《东北林业大学学报》 CAS CSCD 北大核心 2024年第9期99-108,共10页
选取清原县森林内林龄、坡向、坡位基本相同的林分类型,包括天然红松(Pinus koraiensis)林、樟子松(Pinus sylvestris var.mongholica)人工林、蒙古栎(Quercus mongolica)人工林、胡桃楸(Juglans mandshurica)人工林、天然针阔混交林(... 选取清原县森林内林龄、坡向、坡位基本相同的林分类型,包括天然红松(Pinus koraiensis)林、樟子松(Pinus sylvestris var.mongholica)人工林、蒙古栎(Quercus mongolica)人工林、胡桃楸(Juglans mandshurica)人工林、天然针阔混交林(红松和蒙古栎数量比为2∶8),设置无乔木覆盖样地作为对照,对比分析天然条件不同林分土壤粒度组成、平均粒径、标准偏差、偏度、峰态值和(单、多重)分形维数,土壤理化性质空间分布及与分形维数之间的关系。结果表明:有林地表层(0~20 cm)和亚表层(20~40 cm)土壤组成以砂粒为主,粉粒、黏粒次之;粒度特征整体呈现分选状况极好、偏度正和峰态为尖窄的特点,土壤单重分形维数在1.84~2.78之间;有林地土壤平均粒径、单重分形维数及土壤理化性质均高于对照样地,且从针叶林、阔叶林至针阔混交林,上述土壤指标呈现递增趋势;多重分形维数表现为容量维数>关联维数>信息维数;单重分形维数和容量维数与黏粒和粉粒体积分数及土壤理化性质呈显著正相关关系,综合说明土壤细粒物质在有林地的保护中逐渐恢复,且表层土壤的恢复效果较好;多重分形维数分析表明,土壤粒径非理想均匀分布,因此,利用单重分形维数结合多重分形参数评价土壤质量仍有必要。 展开更多
关键词 林分类型 土壤性质 土壤粒度特征 辽东山区
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基于InVEST模型的北京山区土壤侵蚀模拟 被引量:90
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作者 周彬 余新晓 +3 位作者 陈丽华 张振明 吕锡芝 范敏锐 《水土保持研究》 CSCD 北大核心 2010年第6期9-13,19,共6页
为客观认识北京山区森林生态系统的土壤保持功能,基于北京山区森林资源二类调查,应用InVEST模型对北京山区土壤侵蚀状况进行模拟研究,并重点探讨不同森林类型土壤保持功能的大小。结果表明:该模型适用于北京山区的土壤侵蚀模拟,北京山... 为客观认识北京山区森林生态系统的土壤保持功能,基于北京山区森林资源二类调查,应用InVEST模型对北京山区土壤侵蚀状况进行模拟研究,并重点探讨不同森林类型土壤保持功能的大小。结果表明:该模型适用于北京山区的土壤侵蚀模拟,北京山区林地下总的土壤侵蚀量为176万t,平均保持土壤能力为220 t/hm2。各森林类型的保持土壤能力均较高,其中天然混交针叶林保土能力最高,为335 t/hm2,其次是天然侧柏林,为297 t/hm2,而最小的是人工落叶松林,为148 t/hm2。 展开更多
关键词 北京山区 森林类型 土壤侵蚀
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