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Behavior Response of Recreationists to Environment Characteristics of City Parks for Forest Recreation—A Case Study of City Parks of Jingzhou City in China 被引量:1
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作者 薛兴华 《Journal of Landscape Research》 2012年第1期44-48,共5页
By taking city parks of Jingzhou City as an example,city parks,as primary places for citizens' daily forest recreation,should present a certain recreational environment feature under the comprehensive effect of na... By taking city parks of Jingzhou City as an example,city parks,as primary places for citizens' daily forest recreation,should present a certain recreational environment feature under the comprehensive effect of nature,humanity,facilities,location and historical evolution.Through the empirical analysis of recreationists' behaviors in city parks with different environmental characters,it has obtained the differences of recreationists in composition,staying time and contents of recreational activities in different city parks,and that recreationists appear to adapt to the environmental characters.Recreational attractions and demands have manifested their perception towards the environmental characters of city parks.The distribution of recreational satisfaction has demonstrated that experience value of recreationists and environmental characters of city parks are consistent. 展开更多
关键词 CITY parks forest RECREATION environmentAL CHARACTERS Jingzhou CITY
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Ethical Dimensions of Payment for Forest Environmental Services 被引量:1
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作者 WU Shuirong 《Chinese Forestry Science and Technology》 2007年第1期42-56,共15页
The market-based incentive mechanism of payments for forest environmental services (PFES) seeks to capture part of the benefits derived from forest environmental services and channels them to forest resource owners/ma... The market-based incentive mechanism of payments for forest environmental services (PFES) seeks to capture part of the benefits derived from forest environmental services and channels them to forest resource owners/managers who generate these services, thus increases their incentives to conserve and manage forest resources. This paper examines some of the most important ethical issues entailed by PFES mechanism. The analysis shows that PFES may not always benefit the poor due to the comparative disadvantages of the poor and the complicated characteristics of forest ecosystem services. It is important and urgent to take ethical dimensions into account in the PFES approaches and design and develop the pro- poor payment mechanism in order to achieve the two objectives of forest conservation and economic development. 展开更多
关键词 payment for forest environmental services (PFES) ethical dimension EQUITY forest ethics
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Current Status and Progress of Market for Forest Environmental Services
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作者 CHEN Yong CHEN Jie 《Chinese Forestry Science and Technology》 2006年第3期81-92,共12页
With the analyses of the reasons for the emergence of domestic and overseas markets for forest environmental service and its significance, this paper summarizes the progress in the research on the market and reviews t... With the analyses of the reasons for the emergence of domestic and overseas markets for forest environmental service and its significance, this paper summarizes the progress in the research on the market and reviews the operations of the markets for 4 kinds of forest environmental services that are watershed protection services, biodiversity protection services, carbon sequestration services and landscape services. At the end, the paper discusses the major problems arising in the creation of markets for environmental services and the developing tendency. 展开更多
关键词 MARKET forest environmental services watershed protection biodiversity protection carbon sequestration forest landscape
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Towards an integrative approach to evaluate the environmental ecosystem services provided by urban forest 被引量:1
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作者 Samson Roeland Marco Moretti +11 位作者 Jorge Humberto Amorim Cristina Branquinho Silvano Fares Federico Morelli Ulo Niinemets Elena Paoletti Pedro Pinho Gregorio Sgrigna Vladimir Stojanovski Abhishek Tiwary Pierre Sicard Carlo Calfapietra 《Journal of Forestry Research》 SCIE CAS CSCD 2019年第6期1981-1996,共16页
As a Nature-Based Solution,urban forests deliver a number of environmental ecosystem services(EESs).To quantify these EESs,well-defined,reliable,quantifiable and stable indicators are needed.With literature analysis a... As a Nature-Based Solution,urban forests deliver a number of environmental ecosystem services(EESs).To quantify these EESs,well-defined,reliable,quantifiable and stable indicators are needed.With literature analysis and expert knowledge gathered within COST Action FP1204 GreenInUrbs,we proposed a classification of urban forest EESs into three categories:(A)regulation of air,water,soil and climate;(B)provisioning of habitat quality;and(C)provisioning of other goods and services.Each category is divided into EES types:(a)amelioration of air quality;restoration of soil and water;amelioration of the microclimate;removal of CO2 from the air;(b)provision of habitat for biodiversity;support for resilient urban ecosystems;provision of genetic diversity;and(c)provision of energy and nutrients;provision of grey infrastructure resilience.Each EES type provides one or more benefits.For each of these 12 benefits,we propose a set of indicators to be used when analyzing the impacts on the identified EESs.Around half of the 36 indicators are relevant to more than one single benefit,which highlights complex interrelationships.The indicators of wider applicability are tree and stand characteristics,followed by leaf physical traits and tree species composition.This knowledge is needed for the optimization of the EESs delivered by urban forests,now and in the future. 展开更多
关键词 URBAN forestS environmental ECOSYSTEM services INDICATORS
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Evaluation of Ecological Environment Quality of Typical Forest Parks 被引量:1
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作者 Dongmei ZHANG Shuzhen PENG +2 位作者 Weijun ZHAO Mengyuan GAO Junqing HAN 《Agricultural Biotechnology》 CAS 2019年第5期112-116,共5页
Forest tourist areas have an excellent ecological environment,which is conducive to people's physical and mental health.In this study,Fuzhou National Forest Park and Wuying National Forest Park were selected as ty... Forest tourist areas have an excellent ecological environment,which is conducive to people's physical and mental health.In this study,Fuzhou National Forest Park and Wuying National Forest Park were selected as typical representatives of the southern and northern forest parks,respectively,which were compared by qualitative and quantitative research methods from such five aspects as air quality,climate quality,water environment quality,acoustic environment quality and biological population in some forest areas.The results showed that Fuzhou National Forest Park has a concentration of negative oxygen ions much higher than Wuying National Forest Park,and is thus more conducive to people's health;and it has the characteristics of warm and comfortable climate throughout the year and high biodiversity,but the noise is 4.35 db higher than Wuying National Forest Park,and the water quality is slightly poorer than that of Wuying National Forest Park.And its DO value is about 3.89 smaller in autumn than in summer.In Wuying National Forest Park,the concentration of negative oxygen ions is 53.6% lower than Fuzhou National Forest Park,but it is also above the national standard.The climate is only comfortable in June-August,and is colder or cooler in other months.The water quality is better than that of Fuzhou National Forest Park.In particular,the PH value is about 0.38 lower than that of Fuzhou National Forest Park.It has its own unique biological characteristics.The number of tourists in summer is higher,resulting in higher noise in summer than in autumn.The two forest parks in the north and the south are both good places for people to relax and enjoy. 展开更多
关键词 forest TOURISM environmental QUALITY QUALITY EVALUATION ECOLOGICAL environment
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Relationship between species richness and biomass on environmental gradient in natural forest communities on Mt.Xiaolongshan,northwest China 被引量:1
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作者 SUO An-ning JU Tian-zhen GE Jian-ping 《Forestry Studies in China》 CAS 2008年第4期212-219,共8页
We analyzed the relationship between species richness and biomass in natural forest communities at two similar sites on Mt. Xiaolongshan, northwest China. At both sites, a wide range of tree layer biomass levels was a... We analyzed the relationship between species richness and biomass in natural forest communities at two similar sites on Mt. Xiaolongshan, northwest China. At both sites, a wide range of tree layer biomass levels was available by local biomass estimation models. In order to identify underlying mechanism of the species richness-biomass relationship, we included different water resource levels and number of individuals in each plot in our analysis. We sampled 15 and 20 plots (20 m ×20 m), respectively, at both two sites. These plots were sampled equally on the sunny slope and the shady slope. Species richness, number of individuals of each species and diameter at breast height (DBH) as a substitute of biomass of tree layer were recorded in each sample. At one site, the relationship between species richness and biomass was significant on the sunny slope, and this relationship disappeared on the shady slope due to more environmental factors. The relations between species richness and number of individuals and between number of individuals and biomass paralleled the species richness-biomass relation on both slopes. The difference in number of individuals-biomass relationships on the sunny slope and the shady slope revealed "interspecific competitive exclusion" even though the species richness-biomass relationships were not hump-shaped. At the other site, species richness was not related to biomass or to number of individuals. Our study demonstrated the importance of environmental stress and succession of community in the understanding of species diversity-productivity patterns. 展开更多
关键词 BIOMASS species richness environmental factors forest community
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THE ENVIRONMENTAL CHARACTERISTICS OF FOREST LAND AND THE TECHNIQUES OF REFORESTATION IN FIRED LAND IN DAXING'AN MOUNTAINS
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作者 李开隆 《Journal of Northeast Forestry University》 SCIE CAS CSCD 1995年第4期19-23,共5页
Analysis of nature environmental condition and evalwtion of selection and integration ofteclmiques have been carried out in Daxing’an mountains from 1987. The character of soil generaion in this area is influenced by... Analysis of nature environmental condition and evalwtion of selection and integration ofteclmiques have been carried out in Daxing’an mountains from 1987. The character of soil generaion in this area is influenced by the frigid, coniferous forest vegetation, weather, glacier and late soil formation process. Syntliesis teclmiques for high yield plantation include high seedling quality,suitable site preparation and eftbctive protectioll measures for yoimg trees. 展开更多
关键词 forest LAND environmental characteristics Fired land Techniques of REforestATION
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Integrated environmental education for sustainable forest management: the case of Nandi Hills Forests, Kenya 被引量:1
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作者 Julius Gordon TANUI 《Forestry Studies in China》 CAS 2013年第2期152-159,共8页
Environmental education (EE) is a vital dimension of modern day acumen that portends a great promise in solving the myriad environmental resource management challenges at global, regional and local levels. A study w... Environmental education (EE) is a vital dimension of modern day acumen that portends a great promise in solving the myriad environmental resource management challenges at global, regional and local levels. A study was carried out in 18 locations in the Nandi North, Nandi South and Nandi Hills districts of Kenya, which cover the Nandi Hills and Nandi Forests in Nandi County, major water catchments for Lake Victoria. A mixed methodological approach, incorporating both qualitative and quantitative data obtained from focus group discussions, key informant interviews, household survey and observations was embraced in data collection and analysis. The study reveals that there are several strategies that have been adopted by the local population and institutions involved in the management of the Nandi Hills Forests (NHFs) and that these strategies have contributed to an improvement in the perceptions of the local population in terms of the importance of environmental management of the forests. This paper highlights EE as a vehicle for ensur- ing a sustainable management of the Nandi Hills Forests. As such, it illuminates the great potential that lies in sustainably managing the NHFs by integrating formal and informal EE approaches. It further points out the functional gaps in the management of NHFs and proposes best-practices that could be adopted and/or domesticated in NHFs management regimes. 展开更多
关键词 environmental education sustainable forest management forest ecosystems indigenous knowledge
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Effects of forest cover types and environmental factors on soil respiration dynamics in a coastal sand dune of subtropical China 被引量:6
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作者 Wei Gao Zhiqun Huang +2 位作者 Gongfu Ye Xinjian Yue Zhiyong Chen 《Journal of Forestry Research》 SCIE CAS CSCD 2018年第6期1645-1655,共11页
Trees on sand dunes are more sensitive to environmental changes because sandy soils have extremely low water holding capacity and nutrient availability. We investigated the dynamics of soil respiration(Rs) for seconda... Trees on sand dunes are more sensitive to environmental changes because sandy soils have extremely low water holding capacity and nutrient availability. We investigated the dynamics of soil respiration(Rs) for secondary natural Litsea forest and plantations of casuarina,pine, acacia and eucalyptus. Results show that significant diurnal variations of Rsoccurred in autumn for the eucalyptus species and in summer for the pine species, with higher mean soil respiration at night. However, significant seasonal variations of Rswere found in all five forest stands. Rschanged exponentially with soil temperatures at the 10-cm depth; the models explain 43.3–77.0% of Rs variations. Positive relationships between seasonal Rsand soil moisture varied with stands. The correlations were significant only in the secondary forest, and the eucalyptus and pine plantations. The temperature sensitivity parameter(Q10 value) of Rsranged from 1.64 in casuarina plantation to 2.32 the in secondary forest; annual Rswas highest in the secondary forest and lowest in the pine plantation. The results indicate that soil temperatures and moisture are the primary environmental controls of soil respiration and mainly act through a direct influence on roots and microbial activity. Differences in root biomass, quality of litter,and soil properties(pH, total N, available P, and exchangeable Mg) were also significant factors. 展开更多
关键词 Coastal sand dunes Soil respiration Secondary forest PINE CASUARINA ACACIA Eucalyptus plantations environmental factor Q_(10)
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Effects of micro-environmental conditions and forest disturbance on the establishment of two Andean palms in Ecuador
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作者 Diana Rodríguez-Paredes Rommel Montúfar-Galárraga Henrik Meilby 《Open Journal of Ecology》 2012年第4期233-243,共11页
The wax palm (Ceroxylon echinulatum) and palm heart (Prestoea acuminata) are key elements in Andean natural forests. This ecosystem is threatened by deforestation and habitat degradation, thus, it is vital to explore ... The wax palm (Ceroxylon echinulatum) and palm heart (Prestoea acuminata) are key elements in Andean natural forests. This ecosystem is threatened by deforestation and habitat degradation, thus, it is vital to explore the impact of anthropogenic activities on the ecological structure and preferences of these species in order to develop proper conservation strategies. Fifty-seven 400 m2 plots were established in two forest areas, a disturbed forest (n = 30 plots) and an undisturbed forest (n = 27 plots) in the Ecuadorean Andes. Nine micro-environmental variables and the number of individuals of C. echinulatum and P. acuminata in five size classes were recorded in each plot. Logistic regression models helped identify environmental variables that influence the establishment of the species. Results showed that different micro-environmental variables determined the presence of different size classes. Both species were benefitted by the environmental conditions of the disturbed forest. Light availability was important for the establishment of both species, especially for the canopy species (C. echinulatum). This palm was negatively affected by the variable “fallen wood”, while P. acuminata was negatively affected mainly by the steepness of the terrain. The environmental variables for the successful establishment of the studied species that were identified by this study provide clues for the sustainable management of C. echinulatum and P. acuminata in Andean forests. 展开更多
关键词 Andean forest Ceroxylon forest DISTURBANCE Micro-environmental VARIABLES PALM ESTABLISHMENT Prestoea Sustainable Management
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Path Analysis on Environmental Factors Controlling Runoff and Sediment Yields in Shelter Forests in Three Gorges Reservoir Region
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作者 Yaowu TIAN Zhilin HUANG +2 位作者 Lixiong ZENG Wenfa XIAO Xiaodong GENG 《Asian Agricultural Research》 2018年第3期56-61,共6页
Effects of environmental factors such as climate,topography,vegetation and soil in shelter forests in Three Gorges Reservoir Region on runoff and sediment yields were monitored to identify dominant environmental facto... Effects of environmental factors such as climate,topography,vegetation and soil in shelter forests in Three Gorges Reservoir Region on runoff and sediment yields were monitored to identify dominant environmental factors controlling runoff and sediment yields in 15 runoff plots in study area by soil sampling,laboratory analysis,stepwise regression analysis and path analysis,and to establish the main control environmental factors that affect runoff and sediment yields. The results showed that soil bulk density,herbaceous cover,slope,and canopy density were the significant factors controlling runoff,and the direct path coefficient of each factor was ranked as canopy closure(-0. 628) > litter thickness(-0. 547) > bulk density( 0. 509) > altitude( 0. 289). The indirect path coefficient was ranked as soil bulk density( 0. 354) >litter thickness(-0. 169) > altitude( 0. 126) > canopy closure(-0. 104). Therefore,canopy closure and litter thickness mainly had direct effects on runoff,while soil bulk density mainly had indirect effects through their contributions to other factors. Herbaceous cover,litter thickness,slope,canopy density,and altitude were the significant factors controlling sediment yields. The direct path coefficient of each factor was ranked as herbaceous cover(-0. 815) > litter thickness(-0. 777) > canopy closure(-0. 624) > slope( 0. 620). The indirect path coefficient was ranked as slope( 0. 272) > litter thickness(-0. 131) > canopy closure(-0. 097) > herbaceous cover(-0. 084). Therefore,herbaceous cover and litter thickness mainly had direct effects on sediment yields,while slope mainly had indirect effects through their contributions to other factors. All the selected environmental factors jointly explained 85. 5% and 78. 3% of runoff and sediment yield variability,respectively. However,there were large values of remaining path coefficients of other factors influencing runoff and sediment yields,which indicated that some important factors are not included and should be taken into account. 展开更多
关键词 Shelter forest RUNOFF Sediment yield environmental factors Path analysis
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Vegetation-environment relationships in the forests of Chitral district Hindukush range of Pakistan 被引量:8
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作者 Nasrullah Khan Syed Shahid Shaukat +1 位作者 Moinuddin Ahmed Muhammad Faheem Siddiqui 《Journal of Forestry Research》 SCIE CAS CSCD 2013年第2期205-216,共12页
We investigated the composition of plant communities to quantify their relationships with environmental parameters in the Chitral Hindukush range of Pakistan. We sampled tree vegetation using the Point Centered Quart... We investigated the composition of plant communities to quantify their relationships with environmental parameters in the Chitral Hindukush range of Pakistan. We sampled tree vegetation using the Point Centered Quarter (PCQ) method while understory vegetation was sampled in 1.5-m circular quadrats. Cedrus deodara is the national symbol of Pakistan and was dominant in the sampled communities. Because environmental variables determine vegetation types, we analyzed and evaluated edaphic and topographic factors. DCA-Ordination showed the major gradient as an amalgam of elevation (p〈0.05) and slope (p〈0.01) as the topographic factors correlated with species distribution. Soil variables were the factors of environmental significance along DCA axes. However, among these factors, Mg2+ , K + and N2+ contributed not more than 0.054% 0.20% and 0.073%, respectively, to variation along the first ordination axis. We conclude that the principal reason for weak or no correlation with many edaphic variables was the anthropogenic disturbance of vegetation. The understory vegetation was composed of perennial herbs in most communities and was most dense under the tree canopy. The understory vegetation strongly regulates tree seedling growth and regeneration patterns. We recommend further study of the understory vegetation using permanent plots to aid development of forest regeneration strategies. 展开更多
关键词 environmental relationship multivariate analysis cluster analysis ORDINATION anthropogenic factors forest Hindukush range
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环境承载力中介下森林转型赋能区域生态宜居——作用路径与效应识别
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作者 李超 朱震锋 邹成成 《林业经济问题》 北大核心 2024年第3期324-336,共13页
基于中国1999—2018年4次森林资源清查结果及相关统计数据,对中国31个省域(不含港澳台地区)的森林转型指数、环境承载力和生态宜居水平进行测评,然后借助中介效应模型探索森林转型赋能区域生态宜居的作用路径,并测度环境承载力对森林转... 基于中国1999—2018年4次森林资源清查结果及相关统计数据,对中国31个省域(不含港澳台地区)的森林转型指数、环境承载力和生态宜居水平进行测评,然后借助中介效应模型探索森林转型赋能区域生态宜居的作用路径,并测度环境承载力对森林转型赋能区域生态宜居水平的中介效应。结果显示:1999—2018年中国森林转型指数整体呈现稳中有升的发展态势,但不同地区之间水平差异比较明显,西南、东北地区森林转型效果最为显著;中国环境承载力的“U型”曲线演变特征明显,其中西南、华南、华东地区环境承载力较强,华东、华中、华南、华北地区环境承载力在回升阶段表现突出,东北、西南和西北地区在经济快速发展时期,环境承载力呈现下降趋势,突显出资源环境系统脆弱性;中国生态宜居水平总体呈现波动上升态势,其中西南、华北、华东地区上升态势最为明显;环境承载力在森林转型对区域生态宜居水平影响中具有中介作用,森林转型通过提升环境承载力部分解释了其对区域生态宜居水平的促进作用。 展开更多
关键词 生态宜居 森林转型 环境承载力 城镇化 中介效应
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Relationship between diversity of forest plant species and environmental gradient in eastern mountainous area of Heilongjiang Province, China 被引量:2
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作者 WANG Qing-gui XING Ya-juan +1 位作者 ZHOU Xiao-feng HAN Shi-jie 《Journal of Forestry Research》 SCIE CAS CSCD 2006年第3期252-254,共3页
Twenty-three secondary forest communities with different structure were selected in Mao'er Mountain National Park of Heilongjiang Province, China to study the relationship between diversity of forest plant species an... Twenty-three secondary forest communities with different structure were selected in Mao'er Mountain National Park of Heilongjiang Province, China to study the relationship between diversity of forest plant species and environmental gradient. The forest plant species diversity was analyzed by the diversity index, and the environmental factors was quantified by the method of Whittaker's quantification of environmental gradient. Meanwhile, β-diversity indexes of communities were calculated with similar measurements. The results showed that the Shannon-wiener diversity index of forest plant species increased with the increase of the environmental gradient, and the β-diversity indexes of communities showed a liner increase along with the change of environmental gradient. 展开更多
关键词 Species diversity forest plant species Heilongjiang Province Shannon-wiener diversity β-diversity index environmental gradient
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宁波都市区城市群的生态环境问题与森林应对策略
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作者 殷鲁秦 金佳莉 +5 位作者 姜莎莎 古琳 孙睿霖 陈玉飞 史依凡 杨玉坤 《中国城市林业》 2024年第4期100-105,共6页
2021年中欧双方联合开展了中欧绿色城镇化的城市森林应对关键技术研究项目,我国宁波都市区是长三角区域内的重要发展极核之一,其城市群建设也是该研究项目的典型案例。文章在总结宁波都市区“小城镇点状发展-大都市主导发展-城镇化高速... 2021年中欧双方联合开展了中欧绿色城镇化的城市森林应对关键技术研究项目,我国宁波都市区是长三角区域内的重要发展极核之一,其城市群建设也是该研究项目的典型案例。文章在总结宁波都市区“小城镇点状发展-大都市主导发展-城镇化高速发展”的发展历程的基础上,从区域尺度综合分析城市组团之间生态空间、森林质量与景观风貌、外来入侵植物、河流水系生态廊道、城乡居民生态福祉、平原村庄风貌等9个方面的生态环境问题,最后提出群域区生态共建共享共治、中心区生态空间查漏补缺、核心区生态服务能力提升和绿水青山变金山银山挖潜4方面的森林应对策略,以推进长三角区域生态协同、助力美丽杭州湾建设、构建宁波都市区生态安全共同体。 展开更多
关键词 宁波都市区 城市群 生态环境问题 森林应对策略
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退耕还林地生态环境损害评估案例分析及应用 被引量:1
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作者 周海兰 姜苹红 +1 位作者 唐彬 赵文涛 《环境科技》 2024年第1期40-46,共7页
近年来,随着我国经济的高速发展,林地生态环境损害事件日益增加。不同类型的生态系统或同一生态系统在不同区域所提供的生态服务功能侧重均不同,鉴定评估林地生态系统的环境损害价值时应选用不同的测算方法。通过阐述理论公式法和实际... 近年来,随着我国经济的高速发展,林地生态环境损害事件日益增加。不同类型的生态系统或同一生态系统在不同区域所提供的生态服务功能侧重均不同,鉴定评估林地生态系统的环境损害价值时应选用不同的测算方法。通过阐述理论公式法和实际监测法的原理和适用范围及其在生态环境损害评估中的应用,并对量化过程中参数的选取原则与方法进行说明。结合案例分析非法占用退耕还林地导致的生态环境损害范围和程度,计算出2012年~2019年的生态环境损害价值量为205万元。研究退耕还林地生态环境损害典型案例,并将其推广应用于小规模普通林地,对林地生态环境损害案件的鉴定评估环节具有重要引领作用。 展开更多
关键词 生态环境损害 退耕还林地 理论公式法 生态服务功能价值 鉴定评估
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中国式现代化视域下习近平生态文明思想整体系统观及其方法论 被引量:3
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作者 李勇强 《西南大学学报(社会科学版)》 CSSCI 北大核心 2024年第2期1-16,共16页
党的十八大以来,在推进中国式现代化建设的伟大征程中,以习近平同志为核心的党中央坚持系统观念,基于对西方现代化道路的深刻反思和对自然界作为有机系统整体的精准认识,赓续与拓新马克思主义和中华优秀传统文化关于人与自然真实图景的... 党的十八大以来,在推进中国式现代化建设的伟大征程中,以习近平同志为核心的党中央坚持系统观念,基于对西方现代化道路的深刻反思和对自然界作为有机系统整体的精准认识,赓续与拓新马克思主义和中华优秀传统文化关于人与自然真实图景的系统辩证思想,形成和确立了丰富完备、逻辑严密的习近平生态文明思想整体系统观。秉持山水林田湖草沙是生命共同体的系统理念,这一整体系统观锚定生态文明建设和环境治理的目标任务,坚持推进中国式现代化生态文明建设与环境治理的系统层级观,坚持共同体构架的国内外合作治理的系统联动机制,对其内核“是什么”的问题作了精要而又深邃的回答。习近平生态文明思想层层追问中国式现代化生态文明建设之道,彰显了其整体系统思维在回答生态文明建设根本性问题上的强大方法论功能;以系统工程方式“全方位全地域全过程”推进生态文明建设与环境治理的全面系统展开,立体呈现了习近平生态文明思想整体系统观鲜明的方法论特质,为中国式现代化新征程上全面推进美丽中国建设提供了科学思想方法,开拓了中国式现代化恢宏壮丽的生态篇章。 展开更多
关键词 中国式现代化 习近平生态文明思想 整体系统观 生态困局 环境治理 山水林田湖草沙
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基于环境因子优化TSES法选择负样本及其在滑坡易发性评价中的应用
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作者 崔玉龙 朱路路 +1 位作者 徐敏 缪海波 《地质科技通报》 CAS CSCD 北大核心 2024年第3期192-199,共8页
滑坡易发性评价是滑坡灾害防治的重要手段之一,而不合理的滑坡负样本会影响滑坡易发性评价,从而影响到滑坡灾害的防治,因此提供一种合理的负样本选取方法变得尤为关键。以西藏米林市的古滑坡为例,选择高程、坡度、坡向、坡位、距道路距... 滑坡易发性评价是滑坡灾害防治的重要手段之一,而不合理的滑坡负样本会影响滑坡易发性评价,从而影响到滑坡灾害的防治,因此提供一种合理的负样本选取方法变得尤为关键。以西藏米林市的古滑坡为例,选择高程、坡度、坡向、坡位、距道路距离、距断层距离、距水系距离、地形起伏度、地层岩性、土地利用类型10类环境因子,使用Relief算法计算环境因子的贡献值并依据贡献值优化选择环境因子;基于环境因子优化的目标空间外向化采样法(target space exteriorization sampling,简称TSES)选择负样本,作为性能优异的随机森林模型的输入变量;之后结合优化的环境因子和正或负样本预测米林市的滑坡易发性,并用混淆矩阵和ROC曲线评价构建模型的性能。为检验环境因子优化的TSES法的有效性和先进性,采用耦合信息量法和TSES法选择滑坡负样本并构建随机森林模型,与环境因子优化的TSES法构建的随机森林模型进行对比研究。结果表明,环境因子优化的TSES法构建的随机森林模型的评价效果较好,其ACC为93.7%、AUC为0.987,均高于耦合信息量、TSES法构成的模型。环境因子优化的TSES法能够提高模型的精度,解决多因子作为约束条件取样中因子选取的问题,为滑坡易发性评价采集负样本提供了新的思路。 展开更多
关键词 滑坡易发性评价 RELIEF算法 负样本 环境因子优化TSES法 随机森林 古滑坡
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环境因子组合和负样本选取策略对花岗岩区崩岗易发性评价的影响 被引量:1
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作者 郭飞 蒋广辉 +4 位作者 黄晓虎 王秀娟 夏栋 陈洋 李小伟 《农业工程学报》 EI CAS CSCD 北大核心 2024年第1期191-200,共10页
不同环境因子组合和负样本选取策略对崩岗易发性评价结果存在较多不确定性。为探究其对评价结果的影响,该研究以江西省兴国县花岗岩区为例,利用地理探测器探测17个环境因子的统计量q值,根据累计q值百分比大小依次选择4、7、10和17个环... 不同环境因子组合和负样本选取策略对崩岗易发性评价结果存在较多不确定性。为探究其对评价结果的影响,该研究以江西省兴国县花岗岩区为例,利用地理探测器探测17个环境因子的统计量q值,根据累计q值百分比大小依次选择4、7、10和17个环境因子进行组合;利用单随机欠采样、频率比法及改进频率比法等负样本选取策略构建与正样本等量的负样本数据集;采用随机森林模型进行易发性评价,并对评价结果进行对比分析。结果表明:1)3种负样本选取策略下的模型精度随着因子数量的增加先下降再上升,考虑4个环境因子的模型AUC(area under curve)值分别为0.729、0.909和0.909,较最优环境因子组合仅相差0.020~0.038,说明考虑主控环境因子,即可得到较为理想的精度;2)通过频率比法选取的负样本数据集更具合理性;3)研究区内高和极高易发区主要分布在兴国县西南部,而极低易发区主要分布在兴国县北部及东部,这与实际情况较吻合。该研究通过探究不同环境因子组合和负样本选取策略对崩岗易发性评价的影响,可为花岗岩区崩岗的防灾减灾提供科学依据。 展开更多
关键词 易发性 随机森林 崩岗 地理探测器 环境因子组合 负样本选取策略
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植物功能性状对环境的响应及在森林经营中的应用
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作者 李永宁 宗鹏 《中南林业科技大学学报》 CAS CSCD 北大核心 2024年第6期1-10,共10页
植物功能性状被概括为能够影响生态系统功能并且能够反映植物对环境响应的核心植物性状,是植物因为遗传特性或基于可塑性与环境耦合,形成特定的生理、形态方面的性状,更强调植物与生态系统和环境的关系,植物功能性状能够反映植物对环境... 植物功能性状被概括为能够影响生态系统功能并且能够反映植物对环境响应的核心植物性状,是植物因为遗传特性或基于可塑性与环境耦合,形成特定的生理、形态方面的性状,更强调植物与生态系统和环境的关系,植物功能性状能够反映植物对环境变化的响应,在环境与植物间以核心植物属性发挥着中介作用。植物功能性状研究在生态学领域取得了丰硕成果,其对环境响应的规律逐渐明晰,但目前研究主要集中于生态学基础理论上,其应用研究较少且分散,缺少系统的梳理与总结。本研究对植物功能性状的发展与分类进行回顾与整理,在剖析植物功能性状定义的基础上,总结出常见的分类依据包含植物的器官或部位、功能性状获得的难易程度、植物的生存策略、性状与环境的关系、形态和生理特征5大类,并指出植物功能性状的分类系统有待补充与调整;进而结合森林经营的需要,考虑到直观性与可操作性的要求,采取器官分类的方式,对研究较为集中的功能性状进行论述,包括叶功能性状、枝干功能性状、根功能性状与繁殖性状对环境的响应;最后探讨植物功能性状在森林经营中具有为森林更新的树种选择提供依据、为森林采伐的结构调整提供指导、为森林防火与生态保护提供预警、为森林生产力提供有效预测4方面的应用,并从森林经营角度对植物功能性状的应用进行思考与展望。以期为植物功能性状对环境的响应研究以及其在森林经营中的应用提供一定的理论指导。 展开更多
关键词 植物功能性状 环境响应规律 生存策略 森林经营
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