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Evaluating climate-induced productivity of typical ecosystems of the eastern margin of the Qinghai-Tibet Plateau
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作者 ZHENG Huazhu YAO Zhengyu +6 位作者 LU Jungang WU Yongjiao YE Quan ZHAO Hongfei OUYANG Maolin Claudio ODELANG HE Hongming 《Journal of Geographical Sciences》 2026年第1期107-128,共22页
Ecosystems along the eastern margin of the Qinghai-Tibet Plateau(EQTP)are highly fragile and extremely sensitive to climate change and human disturbances.To quantitatively assess climate-induced ecosystem responses,th... Ecosystems along the eastern margin of the Qinghai-Tibet Plateau(EQTP)are highly fragile and extremely sensitive to climate change and human disturbances.To quantitatively assess climate-induced ecosystem responses,this study proposes a Climate-Induced Productivity Index(CIPI)based on the Super Slack-Based Measure(Super-SBM)model using remote sensing data from 2001 to 2020.The results reveal persistently low CIPI values(0.47-0.53)across major ecosystem types,indicating widespread vulnerability to climatic variability.Among these ecosystems,forests exhibit the highest CIPI(0.55),followed by shrublands(0.54),croplands(0.53),grasslands(0.51),and barelands(0.43).The Theil index analysis further demonstrates significant intra-group disparities,suggesting that extreme climatic events amplify CIPI heterogeneity.Moreover,the dominant environmental drivers differ among ecosystem types:the Palmer Drought Severity Index(PDSI)primarily constrains grassland productivity,solar radiation(SRAD)strongly influences shrub and cropland systems,whereas subsurface factors exert greater control in forested regions.This study provides a quantitative framework for evaluating climate-ecosystem interactions and offers a scientific basis for long-term ecological monitoring and security planning across the EQTP. 展开更多
关键词 climate-induced productivity index(CIPI) Super-SBM model ecosystem vulnerability environmental drivers eastern margin of Qinghai-Tibet Plateau
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Study on Construction of Forestry Socialized Service Systems Based on Barnard's Organizational Structure Theory
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作者 WANG Can-fu CHENG Xiao-qiu 《Agricultural Science & Technology》 CAS 2011年第4期603-607,共5页
Construction of forestry socialized service systems is the important content for reform of collective forestry tenure systems.Based on the necessity,possibility and problem of construction of forestry socialized servi... Construction of forestry socialized service systems is the important content for reform of collective forestry tenure systems.Based on the necessity,possibility and problem of construction of forestry socialized service system,according to Barnard's Organizational Structure theory,the path and countermeasure of forestry socialized service system in China are discussed. 展开更多
关键词 FORESTRY Construction of socialized service systems Modern organizational structure theory
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An Analysis on the Forestry Technology Work after Afforestation
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作者 Yulong SHI Xue LI +2 位作者 Rujing YANG Jin HUANG Yi ZHANG 《Asian Agricultural Research》 2020年第6期53-54,57,共3页
In recent years,the concept of"Lucid waters and lush mountains are invaluable assets"has been deeply rooted in the hearts of the people,however,China is still a country with little forest and fragile ecology... In recent years,the concept of"Lucid waters and lush mountains are invaluable assets"has been deeply rooted in the hearts of the people,however,China is still a country with little forest and fragile ecology.This paper expounds the present situation of environmental protection in China,analyzes the main problems and deficiencies in afforestation,puts forward the function of afforestation construction,and makes strategic thinking on environmental protection and afforestation work. 展开更多
关键词 AFFORESTATION Environmental protection Forestry technology
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Significance and Ways of Forest Tending Management in Modern Forestry Construction
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作者 JIANGChuang 《外文科技期刊数据库(文摘版)自然科学》 2022年第8期080-084,共5页
With the rapid development of social economy, China has gradually begun to attach great importance to ecological environment protection and ecological civilization construction. At the same time, innovative forest ten... With the rapid development of social economy, China has gradually begun to attach great importance to ecological environment protection and ecological civilization construction. At the same time, innovative forest tending management techniques and new forest tending management techniques are selected to effectively expand the total green area. However, in reality, there are still some shortcomings in the forest tending management technology. It is necessary to work out all-round management plans from the fields of management and the comprehensive ability of staff, so as to make contributions to improving the environment in China. 展开更多
关键词 forest tending MANAGEMENT forestry construction
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Discussion on Forest Resources Protection and Forestry Sustainable Development
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作者 HUZaihui 《外文科技期刊数据库(文摘版)自然科学》 2022年第1期072-075,共4页
In recent years, various natural disasters have occurred frequently. These are all warnings from nature to human beings. Among them, the environmental pollution problem has become an urgent and urgent problem to be so... In recent years, various natural disasters have occurred frequently. These are all warnings from nature to human beings. Among them, the environmental pollution problem has become an urgent and urgent problem to be solved. In order to gradually restore a good ecological environment, the forest coverage rate in nature reserves will be increased in an all-round way by establishing nature reserves and strengthening the protection and construction of forest resources. There is a close relationship between the development of ecological environment and China's economic development. Protecting ecological resources plays an important role in China's economic development. In order to give full play to the economic benefits of the ecological environment, we should also gradually improve and perfect the ecological benefit compensation mechanism so as to fully realize the sustainable development of the forest reserve. 展开更多
关键词 forest resources PROTECTION sustainable development of forestry
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A new species of the Macrophya malaisei group in Macrophya Dahlbom (Hymenoptera: Tenthredinidae) from China 被引量:1
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作者 Zejian LI Mengmeng LIU Meicai WEI 《Entomotaxonomia》 2025年第3期301-307,共7页
A new species of the Macrophya malaisei group in the genus Macrophya Dahlbom,1835 from Zhejiang in China is described:M.alboclypea Li,Liu&Wei sp.nov.A revised key to the Chinese and Japanese species of the M.malai... A new species of the Macrophya malaisei group in the genus Macrophya Dahlbom,1835 from Zhejiang in China is described:M.alboclypea Li,Liu&Wei sp.nov.A revised key to the Chinese and Japanese species of the M.malaisei group is provided. 展开更多
关键词 TENTHREDINOIDEA Tenthredinine TAXONOMY key
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Review of the Aglaostigma laticinctum subgroup(Hymenoptera:Tenthredinidae)with descriptions of two new species from China 被引量:1
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作者 Mengmeng LIU Zejian LI Meicai WEI 《Entomotaxonomia》 2025年第1期86-95,共10页
Two new species of the Aglaostigma laticinctum subgroup belonging to A.tertium group,are described and illustrated in this study:A.leucogaster Liu,Li&Wei sp.nov.and A.rufitegula Liu,Li&Wei sp.nov.The Aglaostig... Two new species of the Aglaostigma laticinctum subgroup belonging to A.tertium group,are described and illustrated in this study:A.leucogaster Liu,Li&Wei sp.nov.and A.rufitegula Liu,Li&Wei sp.nov.The Aglaostigma laticinctum subgroup is proposed here for the first time,with a brief discussion of its diagnostic features.Additionally,a key to all known species of the A.laticinctum subgroup from China is provided. 展开更多
关键词 TENTHREDINOIDEA SAWFLY taxonomy
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Exploring the spatiotemporal heterogeneity of vegetation changes in subtropical humid karst region under CO_(2)fertilization 被引量:1
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作者 CHEN Meng ZHOU Qiuwen +1 位作者 PENG Dawei YAN Weihong 《Journal of Geographical Sciences》 2025年第1期65-87,共23页
Terrestrial ecosystems heavily depend on vegetation,which responds to carbon dioxide(CO_(2))fertilization in hot and humid regions.The subtropical humid karst region is a hot and humid region;whether and to what exten... Terrestrial ecosystems heavily depend on vegetation,which responds to carbon dioxide(CO_(2))fertilization in hot and humid regions.The subtropical humid karst region is a hot and humid region;whether and to what extent CO_(2)fertilization affects vegetation changes in such regions remains unclear.In this study,we investigated the degree to which CO_(2)fertilization influences vegetation changes,along with their spatial and temporal differences,in the subtropical humid karst region using time-lag effect analysis,a random forest model,and multiple regression analysis.Results showed that CO_(2)fertilization plays an important role in vegetation changes,exhibiting clear spatial variations across different geomorphological zones,with its degree of influence ranging mainly between 11%and 25%.The highest contribution of CO_(2)fertilization was observed in the karst basin and non-karstic region,whereas the lowest contribution was found in the karst plateau region.Previous studies have primarily attributed vegetation changes in subtropical humid karst region to ecological engineering,leading to an overestimation of its contribution to these changes.The findings of this study enhance the understanding of the mechanism of vegetation changes in humid karst region and provide theoretical and practical insights for ecological and environmental protection in these regions. 展开更多
关键词 KARST vegetation changes NDVI driving factors carbon dioxide FERTILIZATION
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Two new species of Dolerus Panzer(Hymenoptera:Tenthredinidae)from China
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作者 Gucheng XIA Meicai WEI 《Entomotaxonomia》 2025年第1期96-102,共7页
Two new species of Dolerinae from Mt.Liupan,Ningxia of China are described:Dolerus liupanicus Wei sp.nov.and D.xiai Wei sp.nov.Dolerus liupanicus is similar to D.purus Jakovlev,1891 but differs from it by the pronotum... Two new species of Dolerinae from Mt.Liupan,Ningxia of China are described:Dolerus liupanicus Wei sp.nov.and D.xiai Wei sp.nov.Dolerus liupanicus is similar to D.purus Jakovlev,1891 but differs from it by the pronotum,tegula,mesoscutal middle lobe and the first abdominal tergum entirely black,the setae of apical sheath almost straight and extending outward at an angle of about 100 degrees,the alaspiculae of middle annuli very large,the middle serrulae each with about 14 to 15 small subbasal teeth.Dolerus xiai is similar to D.japonicus Kirby,1882 but differs from the latter by the fore wing deeply infuscate,the mesepisternum and legs entirely black,the setae on apical sheath blackish brown,the apical sheath in lateral view narrow and strongly tapering toward apex,the middle carina on mesoscutellar appendage not concave,the male abdomen with broad reddish brown rings,and the dorsal apical corner of penis valve convex.A key to species of Dolerinae from Mt.Liupan and nearby area is also provided. 展开更多
关键词 TENTHREDINOIDEA Dolerinae SAWFLIES TAXONOMY key
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Composition Analysis of Lycophytes and Ferns in Yunzhongshan Nature Reserve, Fujian Province
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作者 Jinquan SHEN Minyong LU +4 位作者 Baohua WU Lingming LIN Jinhuo HE Ying FENG Yinbing XIE 《Plant Diseases and Pests》 2025年第2期34-37,共4页
[Objectives]To analyze the composition of lycophytes and ferns in Yunzhongshan Nature Reserve,Fujian Province.[Methods]This study examined the composition of lycophytes and ferns in Yunzhongshan Nature Reserve through... [Objectives]To analyze the composition of lycophytes and ferns in Yunzhongshan Nature Reserve,Fujian Province.[Methods]This study examined the composition of lycophytes and ferns in Yunzhongshan Nature Reserve through field investigations and specimen identification,supplemented by a review of relevant literature.[Results]A total of 84 species of lycophytes and ferns were identified,encompassing 55 genera and 29 families.This included 14 species of lycophytes distributed across 8 genera and 3 families,as well as 70 species of ferns belonging to 47 genera and 26 families.Polypodiaceae and Selaginella were the dominant family and genus,respectively,while oligospecific families and monotypic genera were significant components of lycophytes and ferns in the region.The distribution types of these families were primarily cosmopolitan and tropical.The Germline differentiation degree(SD)was 3.34,and the proportion of rare or endangered species among lycophytes and ferns was 8.33%.[Conclusions]Yunzhongshan Nature Reserve possesses a diverse array of lycophyte and fern species.This study offers valuable scientific insights that can inform efforts related to the conservation of biodiversity,resource utilization and development,species introduction,and system evolution of lycophytes and ferns within the reserve. 展开更多
关键词 NATURE RESERVE LYCOPHYTES FERNS COMPOSITION
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Evaluation of the stand quality of Casuarina equisetifolia in coastal shelterbelts
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作者 CHEN Yu CAO Zuning +6 位作者 CHEN Yu WANG Lun SHAN Liang YU Shuhan YANG Wufa LIU Jian YU Kunyong 《Journal of Mountain Science》 2025年第5期1557-1570,共14页
Coastal areas face challenges in updating and enhancing the quality of coastal shelterbelt forests due to limited soil resource utilization,the biological characteristics of tree species,and the impact of coastal stor... Coastal areas face challenges in updating and enhancing the quality of coastal shelterbelt forests due to limited soil resource utilization,the biological characteristics of tree species,and the impact of coastal storm surges.This study,based on clarifying the connotation of stand quality(SQ)for Casuarina equisetifolia(C.equisetifolia),a typical coastal shelterbelt species,integrates stand growth conditions and structure,applying the AHP-EWM method to construct an SQ evaluation model.The model identifies key factors influencing the quality of C.equisetifolia stands and explores the mechanisms driving their growth processes.The results indicate that mean tree height,mean diameter at breast height,and stand density are key indicators for assessing the SQ of C.equisetifolia stands.The SQ of C.equisetifolia coastal shelterbelt stands varies across different land-sea positions,mainly influenced by stand age and soil nutrient levels.As stand age increases,the SQ initially improves and then declines.Additionally,C.equisetifolia trees growing in nutrient-rich soils exhibit better growth and higher SQ than those in poor soils.The findings of this study provide a theoretical foundation for the management and quality enhancement of coastal shelterbelt forests. 展开更多
关键词 Coastal shelterbelt Casuarina equisetifolia Stand quality Analytic Hierarchy Process-Entropy Weight Method(AHP-EWM) Forest management Forest stand quality
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Two new species in the genus Aglaostigma Kirby(Hymenoptera:Tenthredinidae)from Mts.Nanling,China
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作者 Tong WU Zejian LI +2 位作者 Hejun YE Mengmeng LIU Meicai WEI 《Entomotaxonomia》 2025年第2期200-208,共9页
Two new species in the genus Aglaostigma Kirby(Hymenoptera:Tenthredinidae)are described and illustrated from Mts.Nanling,China:A.luoyoulaii Li,Liu&Wei sp.nov.and A.mengmeng Li&Wei sp.nov.
关键词 SAWFLIES TENTHREDINOIDEA taxonomy
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厦门市山地植被的群落结构分析 被引量:4
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作者 洪志猛 叶功富 +3 位作者 陈文静 潘辉 关庆伟 蔡干强 《中国城市林业》 2007年第5期16-19,共4页
对厦门市山地植被的群落结构分析结果表明,厦门市山地植物群落在外观主要表现为常绿阔叶林相,以常绿阔叶树种为主,其植被以台湾相思群落为主;在乔灌木树种组成上,乔木层优势种主要有台湾相思、朴树、马尾松、土蜜树和榕树等,灌木层优势... 对厦门市山地植被的群落结构分析结果表明,厦门市山地植物群落在外观主要表现为常绿阔叶林相,以常绿阔叶树种为主,其植被以台湾相思群落为主;在乔灌木树种组成上,乔木层优势种主要有台湾相思、朴树、马尾松、土蜜树和榕树等,灌木层优势种主要有豺皮樟、大青、牡荆、桃金娘、黄栀子、盐肤木等,同时,也分析了厦门市山地植被的生物多样性。 展开更多
关键词 山地植被 植物群落 结构分析 厦门市 常绿阔叶树种 台湾相思 常绿阔叶林 生物多样性
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胶合木构件胶接性能及耐久性研究 被引量:4
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作者 罗志华 蔡鑫荣 +2 位作者 张晶 陈静 孙友富 《林产工业》 北大核心 2015年第3期18-21,34,共5页
以层板胶合木为研究对象,采用ASTM D1037、BS EN1087-1,CAN/CSA-0188,ASTM D3434四种人工加速老化方法对单组份聚氨酯胶黏剂胶合而成的层板胶合木构件进行处理。老化处理后,试材的胶合剪切强度下降幅度在27.8%~44.9%之间,下降程度明显... 以层板胶合木为研究对象,采用ASTM D1037、BS EN1087-1,CAN/CSA-0188,ASTM D3434四种人工加速老化方法对单组份聚氨酯胶黏剂胶合而成的层板胶合木构件进行处理。老化处理后,试材的胶合剪切强度下降幅度在27.8%~44.9%之间,下降程度明显高于吸水厚度膨胀率、静曲强度和弹性模量,据此建议将胶合剪切强度作为判定层板胶合木构件耐老化性能的指标。BS EN1087-1老化处理后试材的性能变化情况SASTM D1037较为相似,且用时短,认为是研究层板胶合木构件耐久性较优的人工加速老化处理方法。 展开更多
关键词 层板胶合木构件 胶合性能 加速老化方法 耐久性
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杉木优良家系苗高生长节律分析 被引量:2
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作者 许少嫦 林绪平 +4 位作者 胡德活 池辉云 吴雄光 RUAN Zhi-cai 阮梓材 《中南林学院学报》 CSCD 2001年第2期29-33,共5页
在广东省八一林场试验点 ,对来自全国 11个种子园组的 110个杉木优良家系的苗高生长节律进行了研究 .结果表明 :种子园组间 ,7月初以前存在显著差异 ,以后差异不显著 ;家系间从 6月 1日起始终存在极显著差异 ;与对照比较 ,91.82 %的家... 在广东省八一林场试验点 ,对来自全国 11个种子园组的 110个杉木优良家系的苗高生长节律进行了研究 .结果表明 :种子园组间 ,7月初以前存在显著差异 ,以后差异不显著 ;家系间从 6月 1日起始终存在极显著差异 ;与对照比较 ,91.82 %的家系优于对照 ,经 LSD法检验 ,有 3 9.0 2 %和 2 6.3 3 %的家系分别达较显著和显著水平 ;9.0 9%达极显著水平 ;1年生苗高生长在生长的前期与后期 ,存在极显著相关性 ,10月中下旬起 ,秩次相关系数高且趋于稳定 ,达 0 .862~ 0 .912 . 展开更多
关键词 杉木 优良家系 苗高 生长节律
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Spatial distribution of heavy metals(Cu, Pb, Zn, and Cd)in sediments of a coastal wetlands in eastern Fujian, China 被引量:8
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作者 Lili Zhao Weibin You +8 位作者 Haiqing Hu Wei Hong Xiaojuan LIAO Shihong Xiao Ren Wang Jinbiao Cai Xuncheng Fan Yong Tan Dongjin He 《Journal of Forestry Research》 SCIE CAS CSCD 2015年第3期703-710,共8页
We investigated the spatial distribution (horizontal and vertical concentrations) of copper (Cu), lead (Pb), zinc (Zn), and cadmium (Cd) in five wetland types (mudflat, aquaculture wetland, water area, farm... We investigated the spatial distribution (horizontal and vertical concentrations) of copper (Cu), lead (Pb), zinc (Zn), and cadmium (Cd) in five wetland types (mudflat, aquaculture wetland, water area, farmland wetland and mangrove) from three areas (Ningde, Fuding, and Xiapu), China. Cu concentrations in five wetland types descended in the order: farm wetland, mudflat, aquaculture, water area and mangrove. Pb concentrations decreased in the order: aquaculture, mangrove, farm wetland, mudflat, and water area. Zn content decreased in the order: farm wetland, water area, aquaculture, mudflat and mangrove, and Cd content decreased as follows: mangrove, aquacul- ture, water area, rnudflat, and farm wetland. Comparison of the concentrations of the same heavy metals in different areas showed that the highest Cu (63.75 mg kg-1) and Zn (152.32mgkg-1) concentrations occurred in Ningdecoastal wetlands; Pb (110.58 mg kg-1) and Cd (2.81 mg kg-1) contents were highest in Fuding wetlands, and the average contents of all heavy metals were very low in Xiapu wetlands. Examination of the vertical distribution showed that the Cu content was high in all mudflat layers; Pb and Cd concentrations were highest in aquaculture and mangrove wetlands, respectively, and Zn content was highest in farm wetlands. The spatial distribution of Cu and Zn contents for different areas decreased as follows: Ningde 〉 Fuding 〉 Xiapu, for Pb and Cd were most concentrated in Fuding coastal wetlands. Concentrations of Zn and Cu were highly correlated, while Zn and Cu were not significantly correlated with Pb. 展开更多
关键词 Coastal wetland Heavy metal SPATIALDISTRIBUTION Eastem Fujian Ningde City
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An Insect Imaging System to Automate Rice Light-Trap Pest Identification 被引量:24
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作者 YAO Qing LV Jun +4 位作者 LIU Qing-jie DIAO Guang-qiang YANG Bao-jun CHEN Hong-ming TANGJian 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2012年第6期978-985,共8页
Identification and counting of rice light-trap pests are important to monitor rice pest population dynamics and make pest forecast. Identification and counting of rice light-trap pests manually is time-consuming, and ... Identification and counting of rice light-trap pests are important to monitor rice pest population dynamics and make pest forecast. Identification and counting of rice light-trap pests manually is time-consuming, and leads to fatigue and an increase in the error rate. A rice light-trap insect imaging system is developed to automate rice pest identification. This system can capture the top and bottom images of each insect by two cameras to obtain more image features. A method is proposed for removing the background by color difference of two images with pests and non-pests. 156 features including color, shape and texture features of each pest are extracted into an support vector machine (SVM) classifier with radial basis kernel function. The seven-fold cross-validation is used to improve the accurate rate of pest identification. Four species of Lepidoptera rice pests are tested and achieved 97.5% average accurate rate. 展开更多
关键词 automatic identification imaging system rice light-trap pests SVM cross-validate
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Variation and selection analysis of Pinus koraiensis clones in northeast China 被引量:16
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作者 Deyang Liang Changjun Ding +4 位作者 Guanghao Zhao Weiwei Leng Min Zhang Xiyang Zhao Guanzheng Qu 《Journal of Forestry Research》 SCIE CAS CSCD 2018年第3期609-620,共12页
Understanding genetic variation is important for efficiently selecting excellent clones and utilizing genetic resources during tree breeding. We investigated 16 growth traits of 50 32-year-old Pinus koraiensis clones.... Understanding genetic variation is important for efficiently selecting excellent clones and utilizing genetic resources during tree breeding. We investigated 16 growth traits of 50 32-year-old Pinus koraiensis clones. Analyses of variance showed that all the test traits differed significantly among clones. Average height, diameter at breast height(DBH), and volume of all clones were 10.41 m, 21.30 cm,and 0.148 m3, respectively. Phenotypic coefficients of variation and repeatabilities of traits ranged from 4.37 to48.03% and from 0.013 to 0.900, respectively. There exists significant positive correlations among heights, diameter at different heights(1.3, 3.0, 5.0 m), and volumes; genetic correlation was close to phenotype correlation. Using four growth traits(height, DBH, volume, average crown width)as indices for a comprehensive evaluation, five clones(PK11, PK 19, PK 04, PK 14, and PK 28), whose traits scored in the top 10%, were selected as elite clones. For these clones,genetic gains in height, DBH, volume and crown height were 8.58, 13.02, 32.72 and 3.83%, respectively. These results provide important information for improving P.koraiensis breeding programs. 展开更多
关键词 Genetic variation REPLICATION SELECTION Pinus koraiensis
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Diversity and conservation of Chinese wild begonias 被引量:9
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作者 Daike Tian Yan Xiao +3 位作者 Yi Tong Naifeng Fu Qingqing Liu Chun Li 《Plant Diversity》 SCIE CAS CSCD 2018年第3期75-90,共16页
Begonia, one of the most diverse plant taxa and the fifth or sixth largest angiosperm genus, consists of over1800 accepted species. The number of species recognized within this genus has greatly increased over the pas... Begonia, one of the most diverse plant taxa and the fifth or sixth largest angiosperm genus, consists of over1800 accepted species. The number of species recognized within this genus has greatly increased over the past 20 years, rising from 80 to 200 species in China alone. Based on recent field surveys, the number of begonia species in China is predicted to be between 250 and 300. Given the large number of begonia species that still remain to be described, further taxonomical work is urgently required. This is especially true for Chinese Begonia, in which there is a huge diversity of habitat, habit, plant size, leaf type, flower and fruit morphology, and most species are narrowly distributed in isolated habitats that are subject to negative disturbances from climate change, as well as agricultural and industrial activities. Although the conservation status for the majority of species has been evaluated using the standards of the International Union for Conservation of Nature, the results don't represent the truth in many species, and also about11.5% of which are data-absent. In addition, illegal collection and over-harvesting of wild begonias for ornamental or medicinal use has increased due to the rapid development of internet commerce. Far more often than predicted, these species should be categorized as rare and endangered and require immediate protection. Ex situ conservation of Chinese begonias started in 1995 and over 60% of the total species have been so far introduced into cultivation by several major botanical gardens in China. However, only few research institutions, limited funds and human resources have been involved in Begonia conservation;moreover, no project has conducted reintroduction. Therefore, more conservation-based work remains to be done. Improved conservation of Chinese begonias in the future depends on further field survey, an improved understanding of population diversity, and integrative approaches, including in situ and ex situ conservation, seed banking, and plant reintroduction. Species-targeted conservation zones should be established for endangered species excluded from the existing nature reserves. Additionally, laws pertaining to plant protection should be extended to prevent the illegal collection and transaction of wild plants, particularly for those species with unique habitats and small populations. 展开更多
关键词 BEGONIA GERMPLASM DIVERSITY CONSERVATION Taxonomic status China
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Carbon,nitrogen and phosphorus stoichiometry in Pinus tabulaeformis forest ecosystems in warm temperate Shanxi Province,north China 被引量:9
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作者 Ning Wang Fengzhen Fu +1 位作者 Baitian Wang Ruijun Wang 《Journal of Forestry Research》 SCIE CAS CSCD 2018年第6期1665-1673,共9页
Although carbon(C), nitrogen(N), and phosphorous(P) stoichiometric ratios are considered good indicators of nutrient excess/limitation and thus of ecosystem health, few reports have discussed the trends and the recipr... Although carbon(C), nitrogen(N), and phosphorous(P) stoichiometric ratios are considered good indicators of nutrient excess/limitation and thus of ecosystem health, few reports have discussed the trends and the reciprocal effects of C:N:P stoichiometry in plant–litter–soil systems. The present study analyzed C:N:P ratios in four age groups of Chinese pine, Pinus tabulaeformis Carr., forests in Shanxi Province, China: plantation young forests(AY,<20 year-old); plantation middle-aged forests(AM, 21–30 year-old); natural young forests(NY,<30 year-old); and natural middle-aged forests(NM,31–50 year-old). The average C:N:P ratios calculated for tree, shrub, and herbaceous leaves, litter, and soil(0–100 cm) were generally higher in NY followed by NM,AM, and AY. C:N and C:P ratios were higher in litter than in leaves and soils, and reached higher values in the litter and leaves of young forests than in middle-aged forests;however, C:N and C:P ratios were higher in soils of middle-aged forests than in young forests. N:P ratios were higher in leaves than in litter and soils regardless of stand age; the consistent N:P<14 values found in all forests indicated N limitations. With plant leaves, C:P ratios were highest in trees, followed by herbs and shrubs, indicating a higher efficiency in tree leaf formation. C:N ratios decreased with increasing soil depth, whereas there was no trend for C:P and N:P ratios. C:N:P stoichiometry of forest foliage did not exhibit a consistent variation according to stand age. Research on the relationships between N:P, and P, N nutrient limits and the characteristics of vegetation nutrient adaptation need to be continued. 展开更多
关键词 Pinus tabulaeformis Carr. Forest ecosystem Content of carbon Nitrogen and phosphorus Ecological stoichiometry Warm temperate zone China
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