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Tree species diversity and stand structure along major community types in lowland primary and secondary moist deciduous forests in Tripura,Northeast India 被引量:4
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作者 Koushik Majumdar Uma Shankar Badal Kumar Datta 《Journal of Forestry Research》 CAS CSCD 2012年第4期553-568,共16页
Tree species diversity and population structure at different community types were described and analyzed for primary and secondary lowland moist deciduous forests in Tripura. Overall 10,957 individual trees belonging ... Tree species diversity and population structure at different community types were described and analyzed for primary and secondary lowland moist deciduous forests in Tripura. Overall 10,957 individual trees belonging to 46 family, 103 genera and 144 species were counted at ≥30 cm DBH (diameter at breast height) using 28 permanent belt transects with a size of 1 ha (10 m × 1000 m). Four different tree communities were identified. The primary forests was dominated by Shorea robusta (mean density 464.77 trees.ha^-1, 105 species) and Schima wallichii (336.25 trees.ha^-1, 82 species), while the secondary forests was dominated by Tectona grandis (333.88 trees.ha^-1, 105 species) and Hevea brasiliensis (299.67 trees.ha^-1, 82 species). Overall mean basal area in this study was 18.01m2.ha^-1; the maximum value was recorded in primary Shorea forest (26.21 m2.ha^-1). Mean density and diversity indices were differed significantly within four different communities. No significant differences were observed in number of species, genera, family and tree basal cover area. Significant relationships were found between the species richness and different tree population groups across the communities. Results revealed that species diversity and density were increased in those forests due to past disturbances which resulted in slow accumu- lation of native oligarchic small tree species. Seventeen species were recorded with 〈2 individuals of which Saraca asoka (Roxb.) de Wilde and Entada phaseoloides (L.) Men'. etc. extensively used in local ethnomedicinal formulations. The present S. robusta Gaertn dominated forest was recorded richer (105 species) than other reported studies. Moraceae was found more speciose family instead of Papilionaceae and Euphorbiaceae than other Indian moist deciduous forests. Seasonal phenological gap in such moist deciduous forests influenced the population of Trachypithecus pileatus and capped langur. The analysis of FIV suggested a slow trend of shifting the population of Lamiaceae group by Moraceae species in secondary T. grandis L. dominated community. 展开更多
关键词 diversity and stand structure moist deciduous forest species conservation tree community types
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Anthropogenic disturbances and status of forest and wildlife in the dry deciduous forests of Chhattisgarh state in India 被引量:1
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作者 Chandra Prakash Kala Yogesh Dubey 《Journal of Forestry Research》 SCIE CAS CSCD 2012年第1期45-52,共8页
The advent of modem forces and the changes in socio- economic patterns of forest dwellers have increased the pressures on the forests. In order to mitigate such pressures and also to protect the forests and wildlife t... The advent of modem forces and the changes in socio- economic patterns of forest dwellers have increased the pressures on the forests. In order to mitigate such pressures and also to protect the forests and wildlife the model of protected areas networks has shifted and en- hanced such pressures in the unprotected natural forests due to several reasons. Being a low profile category of protected status and continuous human settlements, the present study highlights the case of dry deciduous forests of Sarguja district of Chhattisgarh state of India. The major objec- tives of this study were to quantify the status of forests and wildlife and also to determine the extent of anthropogenic disturbances faced by the dry deciduous forests of central India. Transect and silent drive count methods were used for sampling wildlife and quadrat method was used for sampling vegetation. Besides, the local uses of various forest pro- duces were also studied in view of understanding the people dependency on forests. The forest vegetation, in the study area, was pre-dominated by Shorea robusta, which had Madhuca indica, Diospyrus melanoxylon and Buchnania lanzan as the major companion species. The forest had either the high girth class mature tree species or the saplings. The low vegeta- tion cover and density were due to the high anthropogenic pressures mainly in the form of heavy livestock grazing and collection of etlmo- botanically important species. The study though reveals that the area is not rich in wildlife and the forest is fragmented, the area still supports some important species, which include many rare and endangered plants and animals. The findings of this study have been discussed in view of the management and conservation of the forest and wildlife in the dry deciduous forests. 展开更多
关键词 dry deciduous forest central India WILDLIFE anthropogenicdisturbances biodiversity conservation
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Light Use Efficiency Model Based on Chlorophyll Content Better Captures Seasonal Gross Primary Production Dynamics of Deciduous Broadleaf Forests
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作者 YANG Rongjuan LIU Ronggao +3 位作者 LIU Yang CHEN Jingming XU Mingzhu HE Jiaying 《Chinese Geographical Science》 2025年第1期55-72,共18页
Gross primary production(GPP)is a crucial indicator representing the absorption of atmospheric CO_(2) by vegetation.At present,the estimation of GPP by remote sensing is mainly based on leaf-related vegetation indexes... Gross primary production(GPP)is a crucial indicator representing the absorption of atmospheric CO_(2) by vegetation.At present,the estimation of GPP by remote sensing is mainly based on leaf-related vegetation indexes and leaf-related biophysical para-meter leaf area index(LAI),which are not completely synchronized in seasonality with GPP.In this study,we proposed chlorophyll content-based light use efficiency model(CC-LUE)to improve GPP estimates,as chlorophyll is the direct site of photosynthesis,and only the light absorbed by chlorophyll is used in the photosynthetic process.The CC-LUE model is constructed by establishing a linear correlation between satellite-derived canopy chlorophyll content(Chlcanopy)and FPAR.This method was calibrated and validated utiliz-ing 7-d averaged in-situ GPP data from 14 eddy covariance flux towers covering deciduous broadleaf forest ecosystems across five dif-ferent climate zones.Results showed a relatively robust seasonal consistency between Chlcanopy with GPP in deciduous broadleaf forests under different climatic conditions.The CC-LUE model explained 88% of the in-situ GPP seasonality for all validation site-year and 56.0% of in-situ GPP variations through the growing season,outperforming the three widely used LUE models(MODIS-GPP algorithm,Vegetation Photosynthesis Model(VPM),and the eddy covariance-light use efficiency model(EC-LUE)).Additionally,the CC-LUE model(RMSE=0.50 g C/(m^(2)·d))significantly improved the underestimation of GPP during the growing season in semi-arid region,re-markably decreasing the root mean square error of averaged growing season GPP simulation and in-situ GPP by 75.4%,73.4%,and 37.5%,compared with MOD17(RMSE=2.03 g C/(m^(2)·d)),VPM(RMSE=1.88 g C/(m^(2)·d)),and EC-LUE(RMSE=0.80 g C/(m^(2)·d))model.The chlorophyll-based method proved superior in capturing the seasonal variations of GPP in forest ecosystems,thereby provid-ing the possibility of a more precise depiction of forest seasonal carbon uptake. 展开更多
关键词 canopy chlorophyll content(Chlcanopy) PHOTOSYNTHESIS gross primary production(GPP) light use efficiency(LUE)model seasonal dynamics deciduous broadleaf forest(DBF)
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Community Dynamics of Seed Rain in Mixed Evergreen Broad-leaved and Deciduous Forests in a Subtropical Mountain of Central China 被引量:9
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作者 Ze-Hao Shen Yuan-Yuan Tang +3 位作者 Nan Lü Jun Zhao Dao-Xing Li Gong-Fang Wang 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2007年第9期1294-1303,共10页
Seed dispersal is a key process within community dynamics. The spatial and temporal variations of seed dispersal and the interspecific differences are crucial for understanding species coexistence and community dynami... Seed dispersal is a key process within community dynamics. The spatial and temporal variations of seed dispersal and the interspecific differences are crucial for understanding species coexistence and community dynamics. This might also hold for the mixed evergreen broadleaved and deciduous forests in the mountains of subtropical China, but until now little existing knowledge is available for this question. In 2001, we chose to monitor the seed rain process of our mixed evergreen broad-leaved and deciduous forest communities in Mount Dalaoling National Forest Park, Yichang, Hubei Province, China. The preliminary analyses show obvious variations in seed rain density, species compositions and timing of seed rain among four communities. The average seed rain densities of the four communities are 2.43 ± 5.15, 54.13 ±182.75, 10.05 ±19.30 and 24.91 ± 58.86 inds/m^2, respectively; about one tenth the values in other studies in subtropical forests of China. in each community, the seed production is dominated by a limited number of species, and the contributions from the others are generally minor. Fecundity of evergreen broadleaved tree species is weaker than deciduous species. The seed rain of four communities begins earlier than September, and stops before December, peaking from early September to late October. The beginning date, ending date and peak times of seed rain are extensively varied among the species, indicating different types of dispersal strategies. According to the existing data, the timing of seed rain is not determined by the climate conditions in the same period, while the density of seed rain may be affected by the disturbances of weather variations at a finer temporal resolution. 展开更多
关键词 interspecific difference Mount Dalaoling mountain mixed evergreen broad-leaved and deciduous forests seed rain species composition weather effect.
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DECIDUOUS AND DECIDUOUS-EVERGREEN FORESTS IN NORTHEAST CHINA
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作者 Chou Yiliang Liu JianweiNortheast Forestry University 《Journal of Northeast Forestry University》 SCIE CAS CSCD 1991年第1期9-16,共8页
Two types of forests in Northeast China is divided in this paper, that is, the deciduous forests in the northern part and the deciduous-evergreen forests in the eastern part. Both distributions of the two types of for... Two types of forests in Northeast China is divided in this paper, that is, the deciduous forests in the northern part and the deciduous-evergreen forests in the eastern part. Both distributions of the two types of forests have also been presented. Meanwhile, the development and succession as well as components of forests have been studied in detail. In the end, the vertical distribution of the deciduous forests have been shown, in which, the near-temperate cold temperate deciduous coniferous forests are distributing in the low elevation area between 450m-600m from the northto the south, the typical Siberian cold temperate deciduous coniferous forests are widely distributing from 450m-820m in the north to 600m-1050m in the south, the humid cold temperate deciduous coniferous forests can only be found in high elevation area from 820m-l 100m in the north to 1050m-1380m in the south, the cold temperate deciduous coniferous open forests can seldom appear at the top of a few peaks. 展开更多
关键词 deciduous forest deciduous-evergreen forest SUCCESSION DISTRIBUTION COMPONENT
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Soil Genesis of Four Alfisols Established in Oak Hickory Forests along Drainages into the Mississippi River in Southeastern Missouri, USA 被引量:2
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作者 Michael Aide 《Journal of Geoscience and Environment Protection》 2021年第2期124-143,共20页
Alfisols in USA taxonomy are “deciduous forest” soils having an argillic horizon with a base saturation in the control section greater than 35%. Alfisols are geographically extensive and support productive agricultu... Alfisols in USA taxonomy are “deciduous forest” soils having an argillic horizon with a base saturation in the control section greater than 35%. Alfisols are geographically extensive and support productive agriculture and deciduous forest ecosystems. Understanding Alfisol genesis, including the presence and intensity of the dominant soil processes, facilitates best management practices that provide stewardship for these soil resources and improves forest and agriculture productivity. Four Alfisols, presently having mature forest settings and located in the central United States along the Mississippi River, were selected for soil and landscape description, classification, and delineation of the dominant soil forming processes. Excavated soils were described and routinely sampled for subsequent physical, chemical, and mineralogical analysis. An aqua regia digestion protocol provided elemental analysis for identifying and inferring the intensity of soil forming processes. The dominant soil forming factors include 1) organic matter accumulation, 2) clay eluviation-illuviation, 3) acidification, 4) base cation accumulation in the A horizons by the forest vegetation, 5) Fe-oxyhydroxide formation, and 6) clay mineral synthesis. Two soils were developed entirely in Peoria loess and two soils were developed in Peoria Loess overlying Ordovician limestone residuum. Ecological site descriptions provide land managers information for evaluating land suitability and the capability to implement different management activities without ecosystem disturbance. Best management practices for the described landforms and based on their Ecological Site Descriptions are presented. 展开更多
关键词 ALFISOLS deciduous forests Peoria Loess Clay Mineralogy Ecological Site Description
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Tropical deciduous forest in Yunnan,southwestern China:Implications for geological and climatic histories from a little-known forest formation 被引量:4
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作者 Hua Zhu Peter Ashton +2 位作者 Bojian Gu Shisun Zhou Yunhong Tan 《Plant Diversity》 SCIE CAS CSCD 2021年第6期444-451,共8页
In the southern mountain ranges of Yunnan province,China,deep valleys of several large rivers create rain shadows with hot dry summers,and are locally designated tropical;towards the north,notably in the Lancang(Upper... In the southern mountain ranges of Yunnan province,China,deep valleys of several large rivers create rain shadows with hot dry summers,and are locally designated tropical;towards the north,notably in the Lancang(Upper Mekong)valley,these regions may experience frost during winter.The woody forest canopy of these valleys is predominantly deciduous,with evergreen elements in the north,where the canopy is open and the forest savanna-like.However,we here present tall forest with a closed deciduous canopy and semi-evergreen subcanopy observed in hot dry valleys of these rivers and their tributaries in the tropical south.The structure and physiognomy of these forests resemble the tall(moist)deciduous forest formation widespread in South Asia and Indo-Burma.Furthermore,these forests are largely composed of tropical elements at both the generic(80%)and the species level(>70%),indicating that these forests are indeed tropical.We originally hypothesized that these isolated forests represent refugia of a pre-Holocene extension of tall(moist)deciduous forest formation of South Asia and Indo-Burma.The sample plot we established to test this hypothesis confirmed that these forests share the structure and physiognomy of the tall(moist)deciduous forest formation;however,the plots also showed that these forests lack the characteristic and dominant species of the formation's Indo-Burmese range.The tree flora,in particular,indicates that both deciduous and evergreen elements are instead mostly derived from the adjacent tropical semi-evergreen forests of tropical southern China;yet they also include an important endemic element,which implies that these forests have survived as refuges possibly since the Pliocene.The exceptional representation of evergreen elements in these forests indicates that they have rarely been subject to hot fires or domestic cattle browsing,adding to the unique nature of the forests and further justifying their strict conservation. 展开更多
关键词 Floristic composition PHYSIOGNOMY BIOGEOGRAPHY Independent species assembly Tall deciduous forest Southwestern China
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Species spatial distributions in a warm-temperate deciduous broad-leaved forest in China 被引量:3
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作者 Huiyan Gu Jiaxin Li +1 位作者 Guang Qi Shunzhong Wang 《Journal of Forestry Research》 SCIE CAS CSCD 2020年第4期1187-1194,共8页
Spatial distribution is fundamental for understanding species coexistence mechanisms in forest communities.Here we comprehensively explored fine-scale spatial patterns of tree species in a secondary warm-temperate dec... Spatial distribution is fundamental for understanding species coexistence mechanisms in forest communities.Here we comprehensively explored fine-scale spatial patterns of tree species in a secondary warm-temperate deciduous broad-leaved forest community in north China.Aggregated distribution patterns were predominant.Species functional traits had no significant effects on their spatial patterns.The aggregation intensity decreased with increasing DBH and abundance.The multivariate linear stepwise regression showed that abundance and maximum DBH were correlated with the aggregation intensity.Our results partially confirm that species attributes(abundance,DBH)and habitat heterogeneity may primarily contribute to spatial patterns and species coexistence in this secondary forest. 展开更多
关键词 Spatial distributions Aggregation intensity Species functional trait Secondary warm-temperate deciduous broad-leaved forest
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Characteristics of bird communities between slope and valley in natural deciduous forest, South Korea
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作者 任信在 许位行 李宇新 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第3期221-224,共4页
Bird communities were surveyed in natural deciduous forest of both slope area and valley area at Mt. Gyebangsan (3740 30 N, 12830 1 E), Gangwon Province, South Korea in winter, spring, summer and autumn from September... Bird communities were surveyed in natural deciduous forest of both slope area and valley area at Mt. Gyebangsan (3740 30 N, 12830 1 E), Gangwon Province, South Korea in winter, spring, summer and autumn from September 2000 to November 2001. The investigating results showed that there existed differences in the bird species composition, richness, bird species diversity, guild structure between slope area and valley area, and the vertical forest structure, especially coverage of understory, and diameter at breast height (DBH) distribution also had significant difference between the two study areas. The differences in habitat structure between the areas are very likely to have influences on how birds used the available habitat. 展开更多
关键词 Bird community Natural deciduous forest SLOPE VALLEY
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Floristic Composition, Structure and Soil Properties of Mixed Deciduous Forest and Deciduous Dipterocarp Forest: Case Study in Madan Watershed, Myanmar 被引量:1
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作者 Kyaw Kyaw Myo San Thwin Nyunt Khaing 《American Journal of Plant Sciences》 2016年第2期279-287,共9页
Patterns of woody regeneration in terms of species composition and diversity were studied in mixed deciduous forest (MDF) and deciduous dipterocarp forest (DDF) in Minbyin reserved forest of Lewe Township. A total of ... Patterns of woody regeneration in terms of species composition and diversity were studied in mixed deciduous forest (MDF) and deciduous dipterocarp forest (DDF) in Minbyin reserved forest of Lewe Township. A total of 57 plant species of MDF belonging to 28 families and 342 individuals and 25 plant species of DDF consist of 15 families and 285 individuals were identified. Plant species diversity was quantitatively higher in the MDF (H' = 3.68) compared to the DDF (H' = 2.39). Tectona grandis showed the highest density (30), dominance (4.40 m<sup>2</sup>) and IVI (27.01) of MDF and Dipterocarpus tuberculatus also composed the highest density (109), dominance (9.02 m<sup>2</sup>) and IVI (81.87) in DDF. The smallest diameter class (10 - 20 cm) comprised with 29 species, 103 individuals in MDF and 18 species, 85 individuals in DDF. The size class distribution displayed a reverse J-shaped pattern. The largest numbers of species were concentrated in the smallest height class in both investigated forests because of height and diameter distribution is closely related. The total densities of seedlings and saplings were 1219 and 531 ha<sup>-1</sup> in MDF and 988 and 444 ha<sup>-1</sup> in DDF respectively. Although soil texture of (40 - 50 cm) and (90 - 100 cm) were sandy clay loam in mixed deciduous forest, the other layers of both investigated forests were sandy loam. 展开更多
关键词 Floristic Composition and Structure Mixed deciduous Forest deciduous Dipterocarp Forest REGENERATION Soil Properties
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Seasonal changes of bioelements in litter and their potential return to green leaves in five species of tropical dry deciduous forest, western India
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作者 J. I. Nirmal Kumar Rita N Kumar +1 位作者 Rohit Kumar Bhoi Kanti Patel 《Journal of Forestry Research》 SCIE CAS CSCD 2010年第1期33-38,I0002,共7页
The Litter nutrient concentrations of N, P, Ca, Mg, K and Na in mature leaves, twigs and reproductive parts and their relationship between senescent and young leaves were investigated in five forest species: Acacia n... The Litter nutrient concentrations of N, P, Ca, Mg, K and Na in mature leaves, twigs and reproductive parts and their relationship between senescent and young leaves were investigated in five forest species: Acacia nilotica, Acacia leucophloea. Tectona grandis, Miliusa tomentosa and Butea monosperma in Indian tropical dry deciduous forest in Western India.. Total dry matter of plant species was recorded and analyzed for N, P, Ca, Mg, K and Na. A. nilotica had the highest concentrations of N in leaf, while ,4. leucophloea had the highest concentrations of Ca and Mg in leaf. The highest concentrations of P in leaf were found in A. nilotica, A. leucophloea and B. monosperma where as lowest in T. grandis and M. tomentosa. No significant differences in K and Na were registered among the species. A marked seasonal variability was ob- served in the concentrations of N, P and K, except for Ca and Mg. Potas- sium is the single element that undergoes leaching and mobilization in all species. Resorped N and P can be used for the production of fresh leaf in the following annual cycle. Nutrient resorption and retranslocation from senescent leaves and litter supports the production of new foliage and increase the fertility of soil. 展开更多
关键词 Tropical dry deciduous forest nutrient concentration senescent and fresh leaves nutrient return nutrient resorption efficiency
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Impacts of canopy structure on the sub-canopy solar radiation under a deciduous forest based on fisheye photographs
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作者 YanLin Zhang XiaoLin Feng +1 位作者 XiaoLi Chang LiMin Tie 《Research in Cold and Arid Regions》 CSCD 2023年第3期150-160,共11页
Forest canopy in a deciduous forest has significant sheltering effects on the sub-canopy solar radiation,significantly influencing the energy balance of snow and permafrost beneath the forest and their spatial distrib... Forest canopy in a deciduous forest has significant sheltering effects on the sub-canopy solar radiation,significantly influencing the energy balance of snow and permafrost beneath the forest and their spatial distribution.This study employs a digital camera mounted with a fisheye lens to acquire photographs at various times in a growth cycle of the forest canopy at three selected sites in a deciduous forest near the Greater Khingan Mountains Forest Ecological Station,Northeast China.The vegetation types and conditions at the selected sites include P1 in Ledum-Claopodium-L.dahurica,P2 in Carex tato-L.dahurica,and P3 in Betula fruticosa-L.dahurica.After necessary image processing,these photographs were used to identify the canopy structure and its impacts on the sub-canopy solar radiation.Results show that fisheye photographs can successfully capture the forest canopy structure and are useful in estimating the sub-canopy solar radiation.The order of sheltering effects from the largest to the smallest on sub-canopy solar radiation at three selected sites is P3,P1,and P2,highly depending on the canopy density.Then sub-canopy solar radiation was calculated using fisheye photographs and an algorithm validated by in-situ observed solar radiation beneath the canopy at P1 and P3.The results are reasonable,although the accuracy seems compromised due to the mismatch of conditions for calculation and observation.Results also show that the mean annual solar radiation above the canopy was about 148.3 W/m2 in 2018,and the mean annual solar radiation values beneath the canopy were about 90.0,123.8,and 61.0 W/m2 at P1,P2,and P3,with only 60%,84%,and 42%of the total solar radiation penetrating through the canopy,respectively.Even in winter,when the trees are leafless,the canopy sheltering effects cannot be ignored in dense forests.Despite the limitations,fisheye photographs and related algorithms are useful in investigating the forest canopy structure and its impacts on sub-canopy solar radiation. 展开更多
关键词 Solar radiation Forest structure Fisheye photograph Sub-canopy deciduous forest
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Land cover mapping of deciduous forest regions using ETM+ data: a case study of Azerbaijan Province, Iran
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作者 Seyed Armin HASHEMI Mir Mozaffar FALLAHCHAI 《Forestry Studies in China》 CAS 2011年第4期299-302,共4页
Up to date information about the existing land cover patterns and changes in land cover over time is one of the prime prerequisites for the preparation of an integrated development plan and economic development progra... Up to date information about the existing land cover patterns and changes in land cover over time is one of the prime prerequisites for the preparation of an integrated development plan and economic development program of a region. By using ETM+ image data from 2002, we provided a land cover map of deciduous forest regions in Azerbaijan Province, Iran. Initial qualitative evaluation of the data showed no significant radiometric errors. Image classification was carried out using a maximum likelihood-based supervised classification method. In the end, we determined five major land cover classes, i.e., grass lands, deciduous broad-leaf forest, cultivated land, river and land without vegetation cover. Accuracy, estimated by the use of criteria such as overall accuracy from a confusion matrix of classification was 86% with a 0.88 Kappa coefficient. Such high accuracy results demonstrate that the combined use of spectral and textural characteristics increased the number of classes in the field classification, also with excellent accuracy. The availability and use of time series of remote sensing data permit the detection and quantification of land cover changes and improve our understanding of the past and present status of forest ecosystems. 展开更多
关键词 land cover deciduous forest regions ETM+ data classification accuracy
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Variability and determinants of vascular plant species composition in patches of old managed oak forest stands dispersed within Scots pine monocultures
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作者 Ewa Stefanska-Krzaczek Rafał Krzaczek +1 位作者 Natalia Mazurek Damian Chmura 《Forest Ecosystems》 CSCD 2024年第6期793-804,共12页
In the temperate zone of Europe,Scots pine forests are expected to occupy the poorest habitats which are unfavourable for deciduous trees.However,as a result of deforestation of the most fertile habitats and the prefe... In the temperate zone of Europe,Scots pine forests are expected to occupy the poorest habitats which are unfavourable for deciduous trees.However,as a result of deforestation of the most fertile habitats and the preference for Pinus sylvestris in silviculture,pine forests have become the dominant feature of the landscape in Central Europe.As a result,the area of optimal habitat for deciduous forest flora has been significantly reduced.Nevertheless,remnant patches of deciduous forest persist as habitat islands within extensive pine forest complexes and may serve as important refugia for meso-and eutrophilic forest species.However,the factors that contribute to the variation in species composition of such habitat islands and their role in maintaining biodiversity remain poorly understood.This paper aims to fill this knowledge gap.The studied deciduous(oak)stands exhibited a diverse vegetation,with species composition influenced by overstorey attributes,oak age,patch location,and the area and circularity of the deciduous forest.Species traits related to environmental variables included mainly preferences for closed or open forests,requirements for soil moisture,reaction,and fertility,and requirements for light conditions.The key message from our research is that oak islands are not simply patches of trees that are different from the surrounding area.Instead,they represent distinct plant communities that have developed to adapt to the prevailing environmental conditions by recruiting species with particular traits.The presence of oak islands within Scots pine monocultures is therefore important for increasing the diversity of the forest complex.The most relevant recommendation from our research for forest management is to maintain as many patches of deciduous tree stands as possible within a single pine forest complex,as even small habitat islands can make a significant contribution to the biodiversity of the forest complex. 展开更多
关键词 Habitat islands deciduous forests Indicator species Environmental variables Species traits
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田林老山中山两类森林凋落物研究 被引量:28
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作者 梁宏温 《生态学杂志》 CAS CSCD 北大核心 1994年第1期21-26,共6页
田林老山中山两类森林凋落物研究梁宏温(广西农学院林学分院,南宁530001)StudiesontheLitterfallofTwoForestTypcsinMid—AltitudeofLaoshanMountaini... 田林老山中山两类森林凋落物研究梁宏温(广西农学院林学分院,南宁530001)StudiesontheLitterfallofTwoForestTypcsinMid—AltitudeofLaoshanMountaininTianlinCounty.¥L... 展开更多
关键词 evergreen and deciduous broadleaved mixed forest.Chinese fir plantation litterfall nutrient element return decompositon rate.
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Microbial Biomass C,N and P in Disturbed Dry Tropical Forest Soils,India 被引量:9
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作者 J.S.SINGH D.P.SINGH A.K.KASHYAP 《Pedosphere》 SCIE CAS CSCD 2010年第6期780-788,共9页
Variations in microbial biomass C (MB-C),N (MB-N) and P (MB-P) along a gradient of different dominant vegeta- tion covers (natural forest,mixed deciduous forest,disturbed savanna and grassland ecosystems) in dry tropi... Variations in microbial biomass C (MB-C),N (MB-N) and P (MB-P) along a gradient of different dominant vegeta- tion covers (natural forest,mixed deciduous forest,disturbed savanna and grassland ecosystems) in dry tropical soils of Vindhyan Plateau,India were studied from January 2005 to December 2005.The water holding capacity,organic C,total N,total P and soil moisture content were comparatively higher in forest soils than in the savanna and grassland sites.Across different study sites the mean annual MB-C,MB-N and MB-P at 0-15 cm soil depth varied from 312.05 ± 4.22 to 653.40 ± 3.17,32.16 ± 6.25 to 75.66 ± 7.21 and 18.94 ± 2.94 to 30.83 ± 23.08 μg g ?1 dry soil,respectively.At all the investigated sites,the maximum MB-C,MB-N and MB-P occurred during the dry period (summer season) and the minimum in wet period (rainy season).In the present study,soil MB-C,MB-N and MB-P were higher at the forest sites compared to savanna and grassland sites.The differences in MB-C,MB-N and MB-P were significant (P < 0.001) among sites and seasons.The MB-C (P < 0.0001),MB-N (P < 0.001) and MB-P (P < 0.0001) were positively correlated with organic C,while the relationship between soil moisture and MB-C,MB-N and MB-P (P < 0.001,P < 0.01 and P < 0.0001,respectively) was negative.The decreasing order of MB-C,MB-N and MB-P along study ecosystems was natural forest > mixed deciduous forest > savanna > grassland.The results suggested that deforestation and land use practices (conversion of forest into savanna and grassland) caused the alterations in soil properties,which as a consequence,led to reduction in soil nutrients and MB-C,MB-N and MB-P in the soil of disturbed sites (grassland and savanna) compared to undisturbed forest ecosystems. 展开更多
关键词 deciduous forest GRASSLAND SAVANNA soil moisture VEGETATION
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Deforestation and fragmentation trends of seasonal dry tropical forest in Ecuador: impact on conservation 被引量:1
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作者 Carlos A.Rivas JoséGuerrero-Casado Rafael M.Navarro-Cerillo 《Forest Ecosystems》 SCIE CSCD 2021年第3期615-627,共13页
Background:Fragmentation and deforestation are one of the greatest threats to forests,and these processes are of even more concern in the tropics,where the seasonal dry forest is possibly one of the most threatened ec... Background:Fragmentation and deforestation are one of the greatest threats to forests,and these processes are of even more concern in the tropics,where the seasonal dry forest is possibly one of the most threatened ecosystems with the least remaining surface area.Methods:The deforestation and fragmentation patterns that had occurred in Ecuadorian seasonal dry forests between 1990 and 2018 were verified,while geographic information systems and land cover shapes provided by the Ecuadorian Ministry of the Environment were employed to classify and evaluate three types of seasonal dry forests:deciduous,semi-deciduous,and transition.The study area was tessellated into 10 km2 hexagons,in which six fragmentation parameters were measured:number of patches,mean patch size,median patch size,total edge,edge density and reticular fragmentation index(RFI).The RFI was also measured both outside and inside protected natural areas(unprotected,national protected areas and protected forest).Moreover,the areas with the best and worst conservation status,connectivity and risk of disappearance values were identified by means of a Getis-Ord Gi*statistical analysis.Results:The deforestation of seasonal dry forests affected 27.04%of the original surface area still remaining in 1990,with an annual deforestation rate of−1.12%between 1990 and 2018.The RFI has increased by 11.61%as a result of the fact that small fragments of forest have tended to disappear,while the large fragments have been fragmented into smaller ones.The semi-deciduous forest had the highest levels of fragmentation in 2018.The three categories of protection had significantly different levels of fragmentation,with lower RFI values in national protected areas and greater values in protected forests.Conclusions:The seasonal dry forest is fragmenting,deforesting and disappearing in some areas.An increased protection and conservation of the Ecuadorian seasonal dry forest is,therefore,necessary owing to the fact that not all protection measures have been effective. 展开更多
关键词 deciduous forest Semi-deciduous forest Remnant forest Patch isolation Habitat loss Protected areas
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The structural characteristics and climatic and human impacts of deciduous oak forests in China 被引量:1
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作者 Guoping Chen Qiong Cai +5 位作者 Wenjing Fang Yuhao Feng Jiangling Zhu Chengjun Ji Zhiyao Tang Jingyun Fang 《Journal of Plant Ecology》 SCIE CSCD 2022年第2期265-276,共12页
Deciduous oak forest is one of the typical vegetation types in temperate and subtropical mountain zones in China.However,the patterns and determinants of the structural characteristics of these forests remain poorly u... Deciduous oak forest is one of the typical vegetation types in temperate and subtropical mountain zones in China.However,the patterns and determinants of the structural characteristics of these forests remain poorly understood.We investigated 682 oak forest plots across China to characterize the community structures of the oak forests and analyze the underlying factors controlling their spatial patterns.Across all plots,the overall mean values were 13.7 cm,10.0 m,1468 stems/ha and 24.3 m^(2)/ha for the diameter at breast height(DBH),height,stem density and total basal area(TBA)of trees,respectively.The average species richness was 6 species/600 m^(2),10 species/100 m^(2) and 4 species/1 m^(2) for the tree,shrub and herb layers,respectively.As latitude increased,the mean tree height,stem density,TBA,tree species richness and shrub species richness decreased,and the mean DBH did not show a significant trend,while species richness of herbs increased significantly.Climatic and anthropogenic variables could explain more variations in mean DBH,mean tree height,TBA,tree species richness,shrub species richness than those in stem density and herb species richness.Further analysis showed that precipitation-related climatic factors were major factors shaping the spatial patterns of community structures.Our findings provide a basis for recognizing the biogeographic patterns of oak forest structures and their responses to global change in China. 展开更多
关键词 QUERCUS deciduous oak forests structural characteristics CLIMATE human disturbance China
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Low net primary productivity of dominant tree species in a karst forest, southwestern China: first evidences from tree ring width and girth increment 被引量:1
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作者 Jian Ni Haiyang Xu Libin Liu 《Acta Geochimica》 EI CAS CSCD 2017年第3期482-485,共4页
Aboveground net primary productivity(ANPP)of two dominant species, one deciduous tree(Platycarya strobilacea) and one evergreen tree(Machilus cavaleriei),was estimated based on the tree-ring width and the girth increm... Aboveground net primary productivity(ANPP)of two dominant species, one deciduous tree(Platycarya strobilacea) and one evergreen tree(Machilus cavaleriei),was estimated based on the tree-ring width and the girth increment as well as allometric functions in a karst evergreen and deciduous broadleaved mixed forest in central Guizhou Province, southwestern China. Results showed that the ANPP increased from 1961 to 2015, especially during the last 20–30 years, but with strong variations. The deciduous tree had higher ANPP than the evergreen tree according to two kinds of estimates by the tree ring and girth increment. The averaged ANPP for these two mature trees was 2.27 kg/individual/year, ca. 8 t/ha/year considering the normal stand density. Such karst forest productivity was lower than the natural subtropical forests in China and in the world. 展开更多
关键词 Biomass increment Tree ring Girth measurement Karst evergreen and deciduous broadleaved forest Allometric functions
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