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Dominance of rock exposure and soil depth in leaf trait networks outweighs soil quality in karst limestone and dolomite habitats
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作者 Min Jiao Jiawei Yan +3 位作者 Ying Zhao Tingting Xia Kaiping Shen Yuejun He 《Forest Ecosystems》 SCIE CSCD 2024年第5期632-641,共10页
Leaf trait networks(LTNs)visualize the intricate linkages reflecting plant trait-functional coordination.Typical karst vegetation,developed from lithological dolomite and limestone,generally exhibits differential comm... Leaf trait networks(LTNs)visualize the intricate linkages reflecting plant trait-functional coordination.Typical karst vegetation,developed from lithological dolomite and limestone,generally exhibits differential communities,possibly due to habitat rock exposure,soil depth,and soil physicochemical properties variations,leading to a shift from plant trait variation to functional linkages.However,how soil and habitat quality affect the differentiation of leaf trait networks remains unclear.LTNs were constructed for typical dolomite and limestone habitats by analyzing twenty-one woody plant leaf traits across fifty-six forest subplots in karst mountains.The differences between dolomite and limestone LTNs were compared using network parameters.The network association of soil and habitat quality was analyzed using redundancy analysis(RDA),Mantle's test,and a random forest model.The limestone LTN exhibited significantly higher edge density with lower diameter and average path length when compared to the dolomite LTN.It indicates LTN differentiation,with the limestone network displaying a more compact architecture and higher connectivity than the dolomite network.The specific leaf phosphorus and leaf nitrogen contents of dolomite LTN,as well as the leaf mass and leaf carbon contents of limestone LTN,significantly contributed to network degree and closeness,serving as crucial node traits regulating LTN connectedness.Additionally,both habitat LTNs significantly correlated with soil nitrogen and phosphorus,stoichiometric ratios,pH,and organic carbon,as well as soil depth and rock exposure rates,with soil depth and rock exposure showing greater relative importance.Soil depth and rock exposure dominate trait network differentiation,with the limestone habitat exhibiting a more compact network architecture than the dolomite habitat. 展开更多
关键词 Leaf trait networks Functional traits Woody plant community KARST DOLOMITE LIMESTONE
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Prediction and driving factors of forest fire occurrence in Jilin Province,China
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作者 Bo Gao Yanlong Shan +4 位作者 Xiangyu Liu Sainan Yin Bo Yu Chenxi Cui Lili Cao 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第1期58-71,共14页
Forest fires are natural disasters that can occur suddenly and can be very damaging,burning thousands of square kilometers.Prevention is better than suppression and prediction models of forest fire occurrence have dev... Forest fires are natural disasters that can occur suddenly and can be very damaging,burning thousands of square kilometers.Prevention is better than suppression and prediction models of forest fire occurrence have developed from the logistic regression model,the geographical weighted logistic regression model,the Lasso regression model,the random forest model,and the support vector machine model based on historical forest fire data from 2000 to 2019 in Jilin Province.The models,along with a distribution map are presented in this paper to provide a theoretical basis for forest fire management in this area.Existing studies show that the prediction accuracies of the two machine learning models are higher than those of the three generalized linear regression models.The accuracies of the random forest model,the support vector machine model,geographical weighted logistic regression model,the Lasso regression model,and logistic model were 88.7%,87.7%,86.0%,85.0%and 84.6%,respectively.Weather is the main factor affecting forest fires,while the impacts of topography factors,human and social-economic factors on fire occurrence were similar. 展开更多
关键词 Forest fire Occurrence prediction Forest fire driving factors Generalized linear regression models Machine learning models
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Endogenous serotonin induced by cold acclimation increases cold tolerance by reshaping the MEL/ROS/RNS redox network in Kandelia obovata
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作者 Junjian Li Huiyu Zhang +4 位作者 Danfei Yue Siyi Chen Yaxin Yin Chunfang Zheng Yan Chen 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第6期73-85,共13页
Cold stress severely limits the distribution of mangrove species worldwide and it remains unclear how mangroves respond and adapt to cold temperatures.In this study,we investigated the effects of cold acclimation and/... Cold stress severely limits the distribution of mangrove species worldwide and it remains unclear how mangroves respond and adapt to cold temperatures.In this study,we investigated the effects of cold acclimation and/or inhibition of serotonin levels on reactive oxygen species(ROS),reactive nitrogen species(RNS),melatonin(MEL)and serotonin(SER)accumulation during cold stress in Kandelia obovata.Morphologic observation and param-eter analysis revealed that cold acclimation mitigated the photoinhibition of photosystem I(PSI)and photosystem II(PSII),maintained optimal ROS and RNS redox homeosta-sis,and increased the contents of SER and MEL in leaves.This suggests that cold acclimation reshapes the MEL/ROS/RNS redox network.In particular,the tryptophan/tryptamine/Ser/N-acetylserotonin/MER pathway was identi-fied as a branch of the MEL synthesis pathway.Inhibition of endogenous SER exacerbated damage caused by cold stress,indicating the crosstalk of SER synthesis and cold acclima-tion.In this study,we report a coordinated regulation of cold stress by a complex defense network in K.obovata. 展开更多
关键词 Cold acclimation SEROTONIN MELATONIN Cold stress MANGROVES
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Geographical Variation in the Advertisement Calls of Leptobrachella ventripunctata(Anura:Megophryidae)in Southwestern China
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作者 Chaobo FENG Tuo SHEN +4 位作者 Lang MU Jing LIU Shize LI Yixin DIAO Haijun SU 《Asian Herpetological Research》 SCIE CSCD 2024年第3期140-151,共12页
In anurans,advertisement calls(ACs)are an essential form of intraspecific communication.This study evaluates geographical variation in the ACs of Leptobrachella ventripunctata in the Guizhou Plateau,southwestern China... In anurans,advertisement calls(ACs)are an essential form of intraspecific communication.This study evaluates geographical variation in the ACs of Leptobrachella ventripunctata in the Guizhou Plateau,southwestern China,and explores correlations between call characteristics,body size,and environmental factors.ACs are simple calls of L.ventripunctata,and apparent differences were observed in the ACs among different geographical populations of L.ventripunctata.The Call duration(CD)revealed a significant positive correlation with altitude and a significant negative correlation with temperature and humidity.Moreover,the Dominant frequency(DF)exhibited a significant negative correlation with altitude and the habitat closure degree and a significant positive correlation with temperature.These variations in ACs between different geographical populations of L.ventripunctata may critically impact the adaptive evolution of species,and the calls may also be relevant for environmental selection. 展开更多
关键词 ANURAN BIOACOUSTICS environmental factors geographical divergence
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Assessing forest cover changes and fragmentation in the Himalayan temperate region: implications for forest conservation and management
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作者 Kaleem Mehmood Shoaib Ahmad Anees +6 位作者 Akhtar Rehman Aqil Tariq Qijing Liu Sultan Muhammad Fazli Rabbi Shao’an Pan Wesam Atef Hatamleh 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第4期128-141,共14页
This study comprehensively assessed long-term vegetation changes and forest fragmentation dynamics in the Himalayan temperate region of Pakistan from 1989 to 2019.Four satellite images,including Landsat-5 TM and Lands... This study comprehensively assessed long-term vegetation changes and forest fragmentation dynamics in the Himalayan temperate region of Pakistan from 1989 to 2019.Four satellite images,including Landsat-5 TM and Landsat-8 Operational Land Imager(OLI),were chosen for subsequent assessments in October 1989,2001,2011 and 2019.The classified maps of 1989,2001,2011 and 2019 were created using the maximum likelihood classifier.Post-classification comparison showed an overall accuracy of 82.5%and a Kappa coefficient of 0.79 for the 2019 map.Results revealed a drastic decrease in closed-canopy and open-canopy forests by 117.4 and 271.6 km^(2),respectively,and an increase in agriculture/farm cultivation by 1512.8 km^(2).The two-way ANOVA test showed statistically significant differences in the area of various cover classes.Forest fragmentation was evaluated using the Landscape Fragmentation Tool(LFT v2.0)between 1989 and 2019.The large forest core(>2.00 km^(2))decreased from 149.4 to 296.7 km^(2),and a similar pattern was observed in medium forest core(1.00-2.00 km^(2))forests.On the contrary,the small core(<1.00 km^(2))forest increased from 124.8 to 145.3 km^(2) in 2019.The perforation area increased by 296.9 km^(2),and the edge effect decreased from 458.9 to 431.7 km^(2).The frequency of patches also increased by 119.1 km^(2).The closed and open canopy classes showed a decreasing trend with an annual rate of 0.58%and 1.35%,respectively.The broad implications of these findings can be seen in the studied region as well as other global ecological areas.They serve as an imperative baseline for afforestation and reforestation operations,highlighting the urgent need for efficient management,conservation,and restoration efforts.Based on these findings,sustainable land-use policies may be put into place that support local livelihoods,protect ecosystem services,and conserve biodiversity. 展开更多
关键词 Natural catastrophes Landsat Change detection Forest fragmentation Landscape fragmentation tool(LFT) AFFORESTATION REFORESTATION
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Determination of Total Flavonoids in Acanthopanax senticosus(Rupr. et Maxim.) Harms by Enzymolysis and Its Technological Optimization
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作者 Li Xinzhi Wang Yudan +4 位作者 Wang Meiliang Liu Tianyang Gao Ruihua Qiu Youwen Zhang Shunjie 《Journal of Northeast Agricultural University(English Edition)》 CAS 2024年第1期53-60,共8页
In order to optimize the ultrasonic extraction technique for the total flavonoid of leaf yellows plus, the contents of 21 leaf yellows plus total flavonoid from four regions in Heilongjiang Province were comparatively... In order to optimize the ultrasonic extraction technique for the total flavonoid of leaf yellows plus, the contents of 21 leaf yellows plus total flavonoid from four regions in Heilongjiang Province were comparatively analyzed. The ultrasonic extraction technology was optimized by Box-Behnken response surface method, and the total flavonoid content of 21 kinds of Acanthopanax senticosus(Rupr. et Maxim.) Harms from different producing areas were analyzed by cluster analysis. The optimal process conditions were determined as ultrasonic time 30 min, solid-liquid ratio 1 : 12 and ultrasonic power 250 W, and the average yield of the total flavonoid was 1.453 mg·g^ (-1). By optimizing the ultrasonic-assisted extraction method, the total flavonoid content from different producing areas was compared in the experiment, which provided certain data support for the optimization of the extraction process in the future and laid a certain theoretical foundation for the quality analysis of Chinese medicinal materials. 展开更多
关键词 Acanthopanax senticosus(Rupr.et Maxim.)Harms total flavonoid Box-Behnken response surface test ultrasonic-assisted extraction
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Patterns and drivers of plant sexual systems in the dry-hot valley region of southwestern China
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作者 Rong Ma Qi Xu +3 位作者 Yongqian Gao Deli Peng Hang Sun Bo Song 《Plant Diversity》 SCIE CAS CSCD 2024年第2期158-168,共11页
Sexual systems play important roles in angiosperm evolution and exhibit substantial variations among different floras. Thus, studying their evolution in a whole flora is crucial for understanding the formation and mai... Sexual systems play important roles in angiosperm evolution and exhibit substantial variations among different floras. Thus, studying their evolution in a whole flora is crucial for understanding the formation and maintenance of plant biodiversity and predicting its responses to environmental change. In this study, we determined the patterns of plant sexual systems and their associations with geographic elements and various life-history traits in dry-hot valley region of southwestern China, an extremely vulnerable ecosystem. Of the 3166 angiosperm species recorded in this area, 74.5% were hermaphroditic,13.5% were monoecious and 12% were dioecious, showing a high incidence of diclinous species. Diclinous species were strongly associated with tropical elements, whereas hermaphroditic species were strongly associated with temperate and cosmopolitan elements. We also found that hermaphroditism was strongly associated with showy floral displays, specialist entomophily, dry fruits and herbaceous plants.Dioecy was strongly associated with inconspicuous, pale-colored flowers, generalist entomophily, fleshy fruits, and woody plants, whereas monoecy was strongly associated with inconspicuous, pale-colored flowers, anemophily, dry fruits, and herbaceous plants. In addition, hermaphroditic species with generalist entomophily tended to flower in the dry season, whereas diclinous species with specialist entomophily tended to flower in the rainy season. However, independent of sexual systems, plants that produce dry fruits tended to flower in the rainy season and set fruits in the dry season, but the opposite pattern was found for fleshy fruit-producing plants. Our results suggest that in the dry-hot valleys, plant sexual systems are associated with geographic elements as well as various life-history traits that are sensitive to environmental change. 展开更多
关键词 Floral traits Fruit type Growth form Pollination system Reproductive phenology
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Evaluating the Impacts of Human Activities on Diversity, Abundance, and Distribution of Large Mammals in Nimule National Park, South Sudan
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作者 Abdallah Gordon Shazali Joseph Mayindo Mayele +1 位作者 Joel Emmanuel Saburi Jubara Nadlin 《Open Journal of Ecology》 2024年第5期483-507,共25页
Globally, human activities have a significant impact on the diversity, abundance, and distribution of large mammals in Protected Areas (PAs). These disturbances increase human pressure on biodiversity and species habi... Globally, human activities have a significant impact on the diversity, abundance, and distribution of large mammals in Protected Areas (PAs). These disturbances increase human pressure on biodiversity and species habitats, highlighting the need for conservation. This study aimed to assess the abundance and distribution of large mammals in different habitat types within Nimule National Park (NNP) and understand the impacts of human activities on them. Data on the abundance and distribution of large mammals and their respective habitat types were collected through line transect surveys. Human activity signs were observed and recorded along the transect lines. To estimate the impacts of human activities on the diversity, abundance, and distribution of large mammal species, as well as to identify any significant differences between them and their habitat types, the study utilized the Kruskal Wallis test, Polynomial multiple regressions, and diversity indices. The findings from the Shannon-Weiner and Simpson indices indicated that large mammal species were more diverse inside the park (H’ = 1.136;D = 0.570) compared to the buffer zone (H’ = 0.413;D = 0.171), with 85% (443 out of 510 samples) recorded within Nimule National Park. The species abundance showed a semi-balanced status (0.58). The diversity results among different habitat types revealed that large mammals were more diverse and highly distributed in both open woodlands (244) and dense woodlands (192), while riverine vegetation had the lowest diversity (8). Statistical tests demonstrated a highly significant difference at a 99% confidence interval (p-value = 0.01) between habitat types and identified species of large mammals. Additionally, the results highlighted the high abundance of Uganda kob (274), baboons (141), and warthog (57) across most habitat types, accounting for at least 75% of their distribution. The most prevalent human activities observed were cattle footprints (27%) and cattle dung (14%). Human footprints and tree cutting combined accounted for 9%, indicating the practice of livestock grazing, poaching, encroachment, and fuelwood collection by local communities. However, these activities did not appear to significantly impact the diversity, abundance, and distribution of large mammals in Nimule National Park. Therefore, it is crucial to foster shared responsibilities and engage relevant stakeholders in the management and conservation of large wildlife species. Regular community awareness programs should be implemented to cultivate a sense of ownership. Moreover, it is recommended that a comprehensive survey be conducted on the population status of all mammal species in Nimule National Park, including its surrounding Buffer Zone. Monitoring the impact of human activities on their behavior and habitats using satellite images should also be carried out at least every five to ten years. 展开更多
关键词 Diversity of Large Mammals Abundance and Distribution IMPACTS Biodiversity Conservation Human Activities Nimule National Park South Sudan
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A Geographic Information Systems approach for classifying and mapping forest management category in Baihe Forestry Bureau, Northeast China 被引量:2
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作者 WANG Shun-zhong SHAO Guo-fan +2 位作者 GU Hui-yan WANG Qing-li DAI Li-min 《Journal of Forestry Research》 SCIE CAS CSCD 2006年第3期211-215,共5页
This paper demonstrates a Geographic Information Systems (GIS) procedure of classifying and mapping forest management category in Baihe Forestry Burea, Jilin Province, China. Within the study area, Baihe Forestry Bu... This paper demonstrates a Geographic Information Systems (GIS) procedure of classifying and mapping forest management category in Baihe Forestry Burea, Jilin Province, China. Within the study area, Baihe Forestry Bureau land was classified into a two-hierarchy system. The top-level class included the non-forest and forest. Over 96% of land area is forest in the study area, which was further divided into key ecological service forest (KES), general ecological service forest (GES), and commodity forest (COM). COM covered 45.0% of the total land area and was the major forest management type in Baihe Forest Bureau. KES and GES accounted for 21.2% and 29.9% of the total land area, respectively. The forest management zones designed with GIS in this study were then compared with the forest management zones established using the hand draw by the local agency. There were obvious differences between the two products. It suggested that the differences had some to do with the data sources, basic unit and mapping procedures. It also suggested that the GIS method was a useful tool in integrating forest inventory data and other data for classifying and mapping forest zones to meet the needs of the classified forest management system. 展开更多
关键词 Classified forest management Key ecological service forest: GIS: Baihe Forestry Bureau
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Integrative transcriptomic and metabolomic analyses reveal the flavonoid biosynthesis of Pyrus hopeiensis flowers under cold stress 被引量:2
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作者 Yongtan Li Jun Zhang +3 位作者 Shijie Wang Haie Zhang Yichao Liu Minsheng Yang 《Horticultural Plant Journal》 SCIE CAS CSCD 2023年第3期395-413,共19页
Low temperature is among the most restrictive factors to limit the yield and distribution of pear. Pyrus hopeiensis is a valuable wild resource.PCA showed that P. hopeiensis had strong cold resistance. In this study, ... Low temperature is among the most restrictive factors to limit the yield and distribution of pear. Pyrus hopeiensis is a valuable wild resource.PCA showed that P. hopeiensis had strong cold resistance. In this study, the mRNA and metabolome sequencing of P. hopeiensis flower organs exposed to different low temperatures were performed to identify changes of genes and metabolites in response to low-temperature stress. A total of 4 851 differentially expressed genes(DEGs) were identified. Trend analysis showed that these DEGs were significantly enriched in profiles 19, 18, 7, 14, 1, 4 and 11. And the KEGG enrichment analysis showed that the DEGs in profile 18 were significantly enriched in flavone and flavonol biosynthesis. Besides, the expressed trends as well as GO and KEGG functional enrichment analyses of DEGs under cold and freezing stress showed significantly difference. Analyses of flavonoid-related pathways indicated that flavonoid structural genes had undergone significant changes. Correlation analysis showed that b HLH and MYB TFs may affect flavonoid biosynthesis by regulating structural gene expression. And PhMYB308 and PhMYB330 were likely candidate repressors of flavonoid biosynthesis by binding to a specific site in bHLH proteins. In total, 92 differentially accumulated metabolites(DAMs) were identified in P. hopeiensis flowers including 12 flavonoids. WGCNA results showed that coral 1, pink and brown 4 modules were closely associated with flavonoids and 11 MYBs and 15 bHLHs among the three modules may activate or inhibit the expression of 23 structural genes of flavonoid biosynthesis. Taken together, the results of this study provided a theoretical basis for further exploration of the molecular mechanisms of flavonoid biosynthesis and cold resistance of P. hopeiensis flower organs and our findings laid a foundation for further molecular breeding in cold-resistant pear varieties. 展开更多
关键词 Pyrus hopeiensis Cold resistance of flower Transcriptome METABOLOME Flavonoid WGCNA
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Effects of site conditions on growth and wood properties of Populus×euramericana cv.'74/76' 被引量:1
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作者 Jianmin Fan Changjun Ding +6 位作者 Shijie Wang Changming Ma Chao Zhang Yongtan Li Jinmao Wang Minsheng Yang Xiaohua Su 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第2期401-414,共14页
The growth and wood properties of 240 individual Populus×euramericana cv.’74/76’(hereafter poplar 107)trees planted in Hebei Plain,China was evaluated.Mean annual increments in height,breast height diameter and... The growth and wood properties of 240 individual Populus×euramericana cv.’74/76’(hereafter poplar 107)trees planted in Hebei Plain,China was evaluated.Mean annual increments in height,breast height diameter and volume,as well as cellulose,hemicellulose and lignin contents,shrinkage,density,bending strength and modulus of elasticity in the heart wood and sap wood.Environmental factors influencing growth and wood properties were analyzed using correlation and stepwise regres sion.The results show that the coefficients of variation(CVs)of growth traits ranged from 10.6 to 22.4%.The CVs of the chemical properties of heartwood ranged from 4.3 to 30.2%,and for sap wood from 3.2 to 27.5%.The CVs of the physical and mechanical properties of heartwood ranged from 8.6 to 31.7%,and for sapwood from 6.4 to 29.9%.The results of one-way ANOVA showed that there were significant differences in growth traits and wood properties among sites.Soil pH,total and available phosphorus,total potassium,and soil organic matter were key soil factors affecting growth and wood properties of poplar 107,whereas mean annual ground temperatures and precipitation were the main climatic factors.To better cultivate poplar 107,area with less annual rainfall,slightly higher temperature and soil pH value close to neutral should be selected. 展开更多
关键词 Poplar clone Environmental factors GROWTH Wood density Mechanical properties Wood chemical composition
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Does pollinator dependence decrease along elevational gradients? 被引量:2
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作者 Yue-Wen Xu Lu Sun +3 位作者 Rong Ma Yong-Qian Gao Hang Sun Bo Song 《Plant Diversity》 SCIE CAS CSCD 2023年第4期446-455,共10页
Plants have long been thought to be less dependent on pollinators for seed production at higher elevations due to adverse pollination environments.However,recent research has yet to consistently support the generality... Plants have long been thought to be less dependent on pollinators for seed production at higher elevations due to adverse pollination environments.However,recent research has yet to consistently support the generality of this expectation.In this study,we asked whether pollinator dependence decreases along an elevational gradient and how it varies with various reproductive traits.To answer these questions,we quantified pollinator-plant associations and various reproductive traits for 112 flowering plants spanning a large elevational gradient(990-4260 m a.s.l.)in the Qinghai-Tibet Plateau.We found that flowering plants in the Qinghai-Tibet Plateau region are highly dependent on pollinators for seed production(76.2%of seed production was contributed by animal pollinators and 44.6%of plants would produce no seed without pollinator visitation).Contrary to our expectation,there was no significant elevational gradient in pollinator dependence index.Although the pollinator dependence index was not significantly correlated with pollen limitation,flower size,floral longevity,or reward type,it was correlated with compatibility status and flowering time.These findings indicate that pollinator dependence does not decrease along an elevational gradient in the Qinghai-Tibet Plateau.Our study also highlights the severe vulnerability of flowering plant seed production to pollinator declines under global change in the Qinghai-Tibet Plateau region,particularly for early-flowering or self-incompatible plants growing at higher elevations(e.g.,subnival belt). 展开更多
关键词 Global change Pollen limitation Pollinator decline Qinghai-Tibet plateau Seed production
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Experiencing urban forests for mitigation of negative emotions of people exposed to seasonal PM_(2.5)in Northeast China
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作者 Jie Zhang Zhi Yang +3 位作者 Yuxiang Sun Zhihui Xu Tengfei Hui Peng Guo 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第5期1245-1261,共17页
Experiencing urban green and blue spaces(GBSs)can be a nature-based solution to improve mental well-being and cope with negative moods for people exposed to PM2.5 pollution.In this study,a total of 1257 photos were co... Experiencing urban green and blue spaces(GBSs)can be a nature-based solution to improve mental well-being and cope with negative moods for people exposed to PM2.5 pollution.In this study,a total of 1257 photos were collected to recognize their posted emotions of Sina Weibo users from 38 parks in 22 cities in Northeast China in 2021,when atmospheric PM_(2.5)and landscape metrics were evaluated for GBSs of each park.Autumn and winter had heavy atmospheric PM_(2.5)pollutions in resource-dependent cities of Liaoning.Net positive emotions(happy minus sad scores)decreased in larger green spaces.The perception of blue space countered the presentation of sadness only for a limited period over four seasons.High elevation decreased the level of happiness presented in winter.Overall,this study confirms that visiting large urban green spaces at low elevations can benefit the perception of positive sentiments for people exposed to PM_(2.5)in autumn.For planning urban forests in Northeast China,more green spaces should be constructed in cities in southern Jilin province to alleviate air PM_(2.5)pollution and gain better well-being of local people. 展开更多
关键词 Urban forest park Mental health and well-being Green and blue infrastructures Sustainable urban forests
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Orchid diversity and distribution pattern in karst forests in eastern Yunnan Province,China
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作者 Qiang Liu Xunfeng Wu +4 位作者 Haitao Xing Kuanbo Chi Wenhua Wang Liang Song Xiaoke Xing 《Forest Ecosystems》 SCIE CSCD 2023年第3期348-356,共9页
Global biodiversity loss and mass extinction of species have raised serious global concerns,especially in fragile ecosystems.Karst forest,a well-known fragile ecosystem,is served as a natural laboratory for biogeograp... Global biodiversity loss and mass extinction of species have raised serious global concerns,especially in fragile ecosystems.Karst forest,a well-known fragile ecosystem,is served as a natural laboratory for biogeographical,ecological,evolutionary,and taxonomic research.However,species richness and distribution patterns in karst forests largely remain unclear.Orchidaceae has been regarded as the“flagship”group of plant diversity.In this study,we use Wanfengshan Nature Reserve in southeast Yunnan,China,as a model to determine the conservation status of orchids in the karst forest by conducting systematic field surveys in the past three years from 2019 to 2022.In total,we identified 78 orchid species in 35 genera in Wanfengshan Nature Reserve.The dominant species were Bulbophyllum andersonii,Eria coronaria,Nervilia mackinnonii and Paphiopedilum micranthum.Multiple life forms were also observed,including epiphyte(14.29%),facultative epiphyte(18.18%),lithophyte(23.38%),and terrestrial(44.15%).Orchid species richness showed a bimodal pattern varied with altitude,the higher richness was recorded at 1,500-1,600 and 1,200-1,300 m,while the minimum was below 1,100 m.Each independent hill is rich in orchid species including‘endemic’species.A total of 25(33.8%)orchid species were considered threatened by the Redlist of Chinese Vascular Plants(Qin et al.,2017),including 3 CR species,5 EN species and 17 VU species.We call for more research addressing the mechanisms of ecological adaption,mycorrhizal interactions,and pollination of orchids in karst forests,and effective ways for recovery and conservation of orchids. 展开更多
关键词 Orchid diversity Limestone forest Resource investigation Threatened status Orchid conservation
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Assessing Forest Cover Distribution, Species Diversity, and Richness of the Buffer Zone for Strategic Forest Management Planning for Nimule National Park, South Sudan
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作者 Joseph Mayindo Mayele Augustine Lokule Bongo 《Open Journal of Ecology》 2023年第11期836-864,共29页
Natural forest ecosystems play an essential role in the conservation of biodiversity of many plants and animals by providing them with habitat and suitable environments. Studies have shown that biodiversity-protected ... Natural forest ecosystems play an essential role in the conservation of biodiversity of many plants and animals by providing them with habitat and suitable environments. Studies have shown that biodiversity-protected areas reduce the loss and degradation of natural habitats to various wild species of plants. This study examined the forest resources in five subzones by conducting tree/shrub species inventory to be able to develop an effective forest management plan for the Buffer Zone Forest Reserve for the sustainable conservation of flora and fauna of Nimule National Park. This is with the view to identify the main tree and shrub species;assess the composition, distribution, and abundance of various tree/shrub species;to determine the species diversity as well as the richness of these areas in terms of growth and performance where DBH and heights of trees/shrubs in the circular sample plots were measured. The results revealed the overall mean DBH and H of 13.83 cm and 6.61 m respectively. The highest number of trees was obtained in subzone B followed by D, while the least were found in subzone A. The overall mean tree/shrub density was 0.83 tons/ha. The mean total basal area and volume per hectare were 3252.74 m<sup>2</sup>/ha and 46,540.82 m<sup>3</sup>/ha respectively. The overall species abundance and distribution indicate Combretum spp, Cedrella spp., Grewia mollis, Acacia Sieberiana, Ziziphus abysinica, and Acacia seyal were the most dominant species, with over 12 species richness at the deposition side of the River Nile, 13 species at the western side of the Nile, the Administration site shows only 7 species, the lowland of Mt. Gordon show over 14 different species, whereas over 10 species were found on the top of Mt. Gordon. The overall mean diversity indices and evenness of H’, D, and E depicted 2.507, 0.871, and 0.840 respectively. These results yielded are relatively moderate. Therefore, conservation efforts are very necessary to improve and maintain the quality of vegetation cover. 展开更多
关键词 Species Diversity Species Abundance Species Richness Buffer Zone Nimule National Park South Sudan
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Determining the Effects of Selected Organic Fertilizer on Growth and Yields of Tomato (Lycopersicon esculentum: Var. Rio Grande Tomatoes) in Mundri West County, Western Equatoria State, South Sudan
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作者 Joseph Mayindo Mayele Felix Rufas Abu 《Agricultural Sciences》 2023年第9期1343-1374,共32页
Worldwide, the demand for agro-organic foods that are healthy, nutritious, and environmentally friendly is increasing dramatically across all nations among consumers. Tomatoes being one of the dietary requirements in ... Worldwide, the demand for agro-organic foods that are healthy, nutritious, and environmentally friendly is increasing dramatically across all nations among consumers. Tomatoes being one of the dietary requirements in almost every meal is not exceptional and its availability in the market all year round is very important to farmers as well as consumers because it is highly demanded as a vegetable par excellence;which is either eaten raw in salads, cooked or processed into liquid ingredients. This study investigates the impact of chicken, goat, and cow manure treatments on tomato plant growth response to height, leaf length, and width, as well as fruit yield. The experimental field trials were conducted over two planting seasons in Mundri West County. It followed a Complete Randomized Design (CRD) approach, consisting of four blocks. Each block contained three treatments replicated four times and a control group. The data of measured parameters from all 16 plots were subjected to one-way Analysis of Variance (ANOVA) using the Gen Stat 14th Edition software. The findings indicate significant differences (P < 0.05) among all the different organic manure applications on tomato plant growth parameters compared to the control group. Chicken manure resulted in the tallest tomato plants (30.1 and 37.9 cm), longest leaves (9.9 and 10.4 cm), and widest leaves (2.1 and 2.5 cm) in both seasons respectively. The study showed plots treated with chicken manure had a highly significant impact (P < 0.05) on the prevalence of aphids (1.0) and white flies (1.4) with the lowest value compared to those with cow and goat manure applied. Additionally, chicken manure led to the highest yields (39.30 and 49.49 tons/ha) in both seasons. Based on these findings, it can be concluded that using chicken manure effectively improves the performance of Rio Grande Tomatoes, and thus, farmers are encouraged to utilize chicken manure to maximize their tomato yields. 展开更多
关键词 Tomato Yield Organic Fertilizers/Manures Tomato Pests Mundri West South Sudan
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Evaluation of land suitability for Moringa oleifera tree cultivation by using Geospatial technology:The case of Dhidhessa Catchment,Abay Basin,Ethiopia
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作者 Mitiku Badasa Moisa Muleta Ebissa Feyissa +5 位作者 Indale Niguse Dejene Firdissa Sadeta Tiye Kiros Tsegay Deribew Zenebe Reta Roba Mengistu Muleta Gurmessa Dessalegn Obsi Gemeda 《Oil Crop Science》 CSCD 2023年第1期45-55,共11页
Land suitability analysis of Moringa oleifera tree cultivation is important to enhance its product,as the demand forthis tree for medicinal values and food sources is increasing worldwide.Therefore,this study aimed to... Land suitability analysis of Moringa oleifera tree cultivation is important to enhance its product,as the demand forthis tree for medicinal values and food sources is increasing worldwide.Therefore,this study aimed to assess suitableland for Moringa oleifera tree cultivation by using the integration of multi-criteria evaluation with geospatialtechnologies in the Dhidhessa catchment,western Ethiopia.Five parameters,namely:slope,land use and landcover(LULC),soil texture,land surface temperature,and rainfall data,were used in this study.The land suitabilityevaluation of Moringa oleifera is classified into three classes as highly suitable,moderately suitable,and notsuitable.The results revealed that,about 344.4 km2(12.2%)of the area is categorized into highly suitable,and2343.7 km2(83%)is moderately suitable for Moringa tree,whereas,137.2 km2(4.9%)is categorized as notsuitable for Moringa oleifera tree cultivation.Hence,based on the finding of the study,we suggested that farmers andother stakeholders can cultivate Moringa oleifera trees in the Dhidhessa catchment. 展开更多
关键词 Moringa tree Medicinal plant Overlay analysis AHP MCE
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Abundance and Dynamics of Soil Labile Carbon Pools Under Different Types of Forest Vegetation 被引量:35
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作者 JIANG Pei-Kun XU Qiu-Fang 《Pedosphere》 SCIE CAS CSCD 2006年第4期505-511,共7页
Soil organic matter (SOM) in forest ecosystems is not only important to global carbon (C) storage but also to sustainable management of forestland with vegetation types, being a critical factor in controlling the quan... Soil organic matter (SOM) in forest ecosystems is not only important to global carbon (C) storage but also to sustainable management of forestland with vegetation types, being a critical factor in controlling the quantity and dynamics of SOM. In this field experiment soil plots with three replicates were selected from three forest vegetation types: broadleaf, Masson pine (Pinus massoniana Lamb.), and Chinese fir (Cunninghamia lanceolata Hook.). Soil total organic C (TOC), two easily oxidizable C levels (EOC1 and EOC2, which were oxidized by 66.7 mmol L-1 K_2Cr_2O_7 at 130-140℃and 333 mmol L-1 KMnO4 at 25℃, respectively), microbial biomass C (MBC), and water-soluble organic C (WSOC) were analyzed for soil samples. Soil under the broadleaf forest stored significantly higher TOC (P (?) 0.05). Because of its significantly larger total soil C storage, the soil under the broadleaf forest usually had significantly higher levels (P (?) 0.05) of the different labile organic carbons, EOC1, EOC2, MBC, and WSOC; but when calculated as a percentage of TOC each labile C fraction of the broadleaf forest was significantly lower (P (?)0.05) than one of the other two forests. Under all the three vegetation types temperature as well as quality and season of litter input generally affected the dynamics of different organic C fractions in soils, with EOC1, EOC2, and MBC increasing closely following increase in temperature, whereas WSOC showed an opposite trend. 展开更多
关键词 DYNAMICS forest soil labile organic C total organic C vegetation system
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Research advance of biomass and carbon storage of poplar in China 被引量:24
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作者 LIANG Wan-jun HU Hai-qing +1 位作者 LIU Fu-jin ZHANG Da-ming 《Journal of Forestry Research》 SCIE CAS CSCD 2006年第1期75-79,共5页
This paper summarized the studies on biomass production, biomass growth models, biomass measurement, biomass and forest density, as well as carbon storage of poplars in China in recent 20 years. The existing problems ... This paper summarized the studies on biomass production, biomass growth models, biomass measurement, biomass and forest density, as well as carbon storage of poplars in China in recent 20 years. The existing problems on research of poplar biomass are discussed and some suggestions for enhancing biomass of poplars are put forward. 展开更多
关键词 POPLAR BIOMASS Carbon Storage REVIEW
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