The genetic diversity and population structure of the Dybowski＇s frog（Rana dybowskii） were investigated by using 11 polymorphic microsatellite loci.Total 75 individuals were sampled from six populations in Lesser K...The genetic diversity and population structure of the Dybowski＇s frog（Rana dybowskii） were investigated by using 11 polymorphic microsatellite loci.Total 75 individuals were sampled from six populations in Lesser Khingan Mountains and Changbai Mountains,China.Results showed that allele number of the 11 microsatellite loci was in the range of 2-10 in all populations,with the mean of 5.6.The average expected heterozygosity（HE） was 0.572,indicating a moderate polymorphism.The results of genetic differentiation coefficient（FST） showed that population genetic differentiation was significant between Changbai and Lesser Khingan Mountains（p〈0.001）.This result was verified further by Nei＇s genetic distance（DA） based on UPGMA phy-logenetic trees and by AMOVA analysis.In conclusion,the populations distributed in Lesser Khingan Mountains and Changbai Mountain are proposed to be two distinct management units（MUs） for their protection and management.展开更多
Amphibia ns play a key role in structuring biological assemblages of agricultural landscapes,but they are threatened by global agricultural intensification.Landscape structure is an important variable in flue ncing bi...Amphibia ns play a key role in structuring biological assemblages of agricultural landscapes,but they are threatened by global agricultural intensification.Landscape structure is an important variable in flue ncing biodiversity in agricultural la ndscapes.However,in the Yangtze River Delta,where a"farmland-orchard-fishpond"agricultural pattern is common,the effects of landscape construction on anuran populations are unclear.In this study,we examined the effects of agricultural landscape parameters on the abundance and body condition of the rice frog(Fejervarya multistriata),which is a dominant anuran species in farmland in China.Employing a visual encounter method,we surveyed rice frog abundance for 3years across 20 agricultural landscapes.We also calculated the body condition index(BCD of 188 male frog individuals from these agricultural landscapes.Landscape variables,comprising landscape compositional heterogeneity(using the Shannon diversity in dex of all land cover types except buildings and roads),Ian dscape con figurational heterogeneity(using landscape edge density),breeding habitat diversity(using the number of 5 waterbody types available as breeding habitats),and areas of forest were also measured for each 1-km radius landscape.We found that the amount of forest in each agricultural Iandscape had a sign讦icant positive relationship with rice frog abundance,and breeding habitat diversity was positively related to the BCI of male rice frogs.However,body condition was negatively impacted by landscape configurational heterogeneity.Our results suggested the importance of nonagricultural habitats in agricultural landscapes,such as waterbodies and forest,to benefit rice frog population persistenee.展开更多
An intelligent method of shifting cultivation to regenerate vegetation after a long fallow period is critical information for restoration strategies. The literature review identified that the assessment of woody plant...An intelligent method of shifting cultivation to regenerate vegetation after a long fallow period is critical information for restoration strategies. The literature review identified that the assessment of woody plant species on abandoned farmland has never been done before in Kamwatta, Moruca Region 1. In addition, more information should be available in indigenous communities and at the national level, including more documentation of the utilization of natural resources by the Warrau community. This study assessed the valuable woody plant species that grew during the fallow periods. Nine farmlands were randomly selected along a 100 m transect, each with varying fallow periods. In order to collect information on the age of farm abandonment, the researcher employed a mixed-methods approach. First, we found how long each farm had been fallow by administering a semi-structured questionnaire. Then, we conducted a flora survey to gain information on the variety and abundance of valuable plants using the age of farm abandonment as a dependent variable. The data analysis included the number of valuable woody trees with a diameter of >10 cm, seedlings and saplings with a diameter of <10 cm, the location of identified trees, and the uses of identified tree species. Microsoft Excel was used to code and analyze the questionnaire, while QGIS, Shannon’s Index of Diversity, and Simple Linear Regression were used to analyze the inventory data. The results showed that the respondents listed 38 valuable woody species, and 79% occurred in the studied area. The field verification revealed that the dominant family in the area was Mimosaceae. Species abundance increased with fallow up to 10 years before declining in the latter years. Plant diversity and abundance had a weak relationship with the age of abandoned farmlands for woody trees, while the seedlings and saplings showed no relationship.展开更多
In order to systematically study the diversity of plant communities in park green space,78 plant communities of 10 representative parks in Wuhan City were investigated.The total 449 species belonging to 275 genera and...In order to systematically study the diversity of plant communities in park green space,78 plant communities of 10 representative parks in Wuhan City were investigated.The total 449 species belonging to 275 genera and 112 families were found in this investigation.The communities were divided into 35 dominant-species,13 life-forms and 6 vegetation-forms.The community structures and the composition of dominant species were also studied.The results showed that the shortages of the low diversity,high proportion of exotic species and simple community structures appeared in plant community of park green space in Wuhan City.It is proposed that species,especially native ones,should be abundant to keep a high level species diversity.At the same time,more simulated native communities should be utilized to build the natural,multi-layers,bright local vegetation characteristics landscape of urban parks.展开更多
Native species may decline quickly when confronted with an exotic species to which they are not adapted. The extent of decline may depend on the abundance of an invader and the length of time since it first arrived in...Native species may decline quickly when confronted with an exotic species to which they are not adapted. The extent of decline may depend on the abundance of an invader and the length of time since it first arrived in the community （residence time）, and the interaction between these two variables. We tested these effects using data on the effects of American bullfrog Lithobates catesbeianus invasion on native frog communities in 65 permanent lentic waters on islands in the Zhoushan Archipel- ago, China. We examined variation in native frog abundance and species richness in relation to features of the American bullfrog invasion, habitat disturbance, characteristics of the water body and fish communities and the presence of red swamp crayfish. Bullfrog invaded sites had lower native frog density and species richness, higher submerged vegetation cover and greater fre- quency of repairs to the water body than did non-invaded sites. The minimum adequate general linear mixed models showed that both native frog density and species richness were negatively related to post-metamorphosis bullfrog density, and that native frog species richness was also positively related to the vegetation cover. There was no effect on either native frog density or species richness of residence time or its interaction with bullfrog density, or of the abundance of bullfrog tadpoles. The results suggested that post-metamorphosis bullfrogs had impacts on native frog communities in the islands, and that the extents of these impacts are proportional to post-metamorphosis bullfrog density展开更多
In the Indian Himalayan Region, th studies focused on diversity of the plants used fo treating liver diseases/ailments have not been carried out so far. Therefore, the present attempt has been made to study the divers...In the Indian Himalayan Region, th studies focused on diversity of the plants used fo treating liver diseases/ailments have not been carried out so far. Therefore, the present attempt has been made to study the diversity, distribution pattern and conservation status of the plant species used fo treating liver diseases/ailments in that region. A tota of 138 species (35 species of trees, 22 shrubs and 8 herbs) belonging to 98 genera in 60 families hav been recorded. Amongst the families, Euphorbiacea (9 species), and altitudinal zone <1,800 m, (i.e., 11 species) are rich in species. Traditionally, variou plant parts, such as roots/rhizomes/tubers (46 species), leaves (31), whole plants (30), barks (15) fruits (13), seeds and unspecified parts (8 each), and inflorescence (1) are used for the treatment of live diseases/ailments. 34 species are native, 3 ar endemic and 15 near endemic. 7 species ar categorized as Critically Endangered (Betula utilis) Endangered (Podophyllum hexandrum, Ephedra gerardiana, and Nardostachys grandiflora) and Vulnerable (Bergenia ligulata, B. stracheyi, and Hedychium spicatum) using new IUCN criteria Available chemical composition of plant parts used fo the treatment of liver diseases/ailments have beengiven. Assessment of the populations of threatened species, development of an appropriate strategy, action plan for the conservation and sustainable utilization of such components of plant diversity are suggested.展开更多
The developmental activities, particularly the construction of hydroelectric projects are causing a great loss of biodiversity in the Indian Himalayan Region. The Himaehal Pradesh, a part of IHR is well known for the ...The developmental activities, particularly the construction of hydroelectric projects are causing a great loss of biodiversity in the Indian Himalayan Region. The Himaehal Pradesh, a part of IHR is well known for the development of hydroelectric projects. The Parbati H.E. Project is amongst the major projects of the State. The different stages of the project are all causing loss of biodiversity of the area. Stage Ⅲ of the Parbati H.E. Project is a run of the river scheme on the Sainj River downstream of Power House of Parbati H.E. Project Stage Ⅱ. The project shall utilize regulated discharge of Parbati H.E. Project Stage Ⅱ and inflow of River Sainj for power generation, and has been contemplated as a peaking station operating in tandem with Stage Ⅱ. The present study has been undertaken to see the impact of hydroelectric project on the biodiversity, particularly on medicinal plants. A total of 104 species of medicinal plants, belonging to different life forms, i.e., trees （23 spp.）, shrubs （22 spp.）, herbs （57 spp.） and ferns （2 spp.） were recorded. The species have been analyzed and studied for their distribution, classification, altitudinal zones, part （s） used, indigenous uses, nativity, endemism and rarity.Different parts of these species, such as whole plants, roots （including rhizomes and tubers）, leaves, flowers, fruits, seeds, stems, barks, spikes, nuts and insect galls are used by the inhabitants for curing various diseases and ailments. 3o species are native to the Himalayan region, 9 species native to the Himalayan region and adjacent countries also and 65 species are non-natives. 9 species are near endemics. Considering the whole Himalaya as a biogeographie unit （sensu lato）, the near endemics are endemic to the Himalaya. Among these species, Zanthoxylum armature is categorized as Endangered and Valeriana wallichii as Vulnerable. Hedychium spicatum, Rhus javanica, Berberis lycium, Thalictrum foliolossum, Salvia lanata, Rubia cordifolia and Bergenia ligulata may be considered as threatened species due to their over exploitation for trade. 90 species are propagated by seeds, 8 species by seeds and rhizomes/roots/tubers, 4 species by seeds and cuttings, and 2 species by sori. A management plan for the cultivation and conservation of the medicinal plants in the dam submergence area, and the commercially viable medicinal plants with high value in the catchment area is suggested.展开更多
In the Indian Himalayan Region predominantly rural in character, livestock is one of the main sources of livelihood and integral part of the economy. Livestock mostly rely on fodder from wild. The diversity, distribut...In the Indian Himalayan Region predominantly rural in character, livestock is one of the main sources of livelihood and integral part of the economy. Livestock mostly rely on fodder from wild. The diversity, distribution, utilization pattern, nativity, endemism, rarity, seasonality of availability, nutritive values, perceived economic values and pressure use index of livestock have not been studied. The present study attempts to enumerate 150 species of fodder representing trees (51 spp.), shrubs (54 spp.) and herbs (45 spp.). Poaceae (19 spp.) and Fabaceae (13 spp.) amongst families and Salix (6 spp.), Ficus, Clematis, and Desmodium (5 spp., each) amongst genera are rich in species. Maximum species were found in the 1801 ~ 2600 m zone, and the remaining two zones showed relatively low diversity. Out of the 150 species, 109 are used in summer, 5 winter and 36 throughout year. During rainy season, mostly grasses are used as fodder. Only 83 species are native to the Himalayan region, one species, Strobilanthus atropuroureus is endemic and 35 species are near endemic. The nutritive values of the fodder species were reviewed, and economic values and status of the species were also assessed. The pressure use index of the species was calculated on the basis of cumulative values of the utilization pattern, altitudinal distribution, availability, status, nativity and endemism. Amongst the species, Grewia oppositifoilia, Morus serrata, Indigofera heterantha, Quercus leucotrichphora, Ulmus villosa, U. wallichiana and Aesculus indica showed highest PUI indicating high preference and pressure. Season wise prioritization of the species for different altitudinal zones has been done. Appropriate strategy and action plan have been suggested for the conservation and management of fodder species.展开更多
Although the relationship between invasive alien species (IAS) and plant community structure has attracted considerable interest, the impacts of IAS on abundance and diversity of resident plant communities in species ...Although the relationship between invasive alien species (IAS) and plant community structure has attracted considerable interest, the impacts of IAS on abundance and diversity of resident plant communities in species rich-ecosystems, such as tropical wetlands are poorly understood. Consequently, this has impeded development of improved management strategies and successful restoration of invaded tropical wetlands. Therefore, data on vegetation were collected from 60 plots of 20 × 50 m to study the impacts of alien invasive grass Echinochloa colona (L.) Link abundance on plant community abundance, richness, evenness and diversity of resident plant species within grasslands of the Kilombero Valley wetland, Tanzania. Moreover, the impacts of abundance of E. colona on plant functional groups (i.e. graminoids, forbs and shrubs) richness were also explored. Generalized linear models showed that community richness, evenness, diversity and abundance of resident species were negatively related to the E. colona abundance. There was a negative relationship between richness of graminoids and shrubs and the abundance of E. colona. Similarly, the abundance of graminoids, forbs and shrubs is related negatively to the abundance of E. colona. Given that most of the community and functional group attributes of resident plants is related negatively to E. colona abundance, improved management strategies should be developed to minimize the abundance and further spread of E. colona to restore and conserve wetland biodiversity.展开更多
The Brazilian state of Acre has an extensive natural reserve of bamboo,making it one of the largest in loco gene banks.The aim of this study was to characterize the structure and genetic diversity of Guadua weberbauer...The Brazilian state of Acre has an extensive natural reserve of bamboo,making it one of the largest in loco gene banks.The aim of this study was to characterize the structure and genetic diversity of Guadua weberbaueri Pilg.in two populations,one native(FAPB)and the other anthropized(FAPBA),using ISSR markers.The results show that the FAPB population exhibited higher values for all estimates of population diversity.However,the FAPBA population also showed high heterozygosity,corroborated by estimated gene flow(Nm=3.9)between the populations.The study of the association between Nei’s genetic distances and the geographic distances between the populations were significantly correlated(r=0.45,p=0.01),corroborated by the dendrogram revealing two distinct groups corresponding to the collection sites,without mixing classes between populations in the same group.As for the coancestry coefficient,pairs of individuals in the first distance class were positive and significant,indicating that plants that are geographically closer share common alleles with a frequency greater than by chance,which means that there is a tendency that geographically closer individuals are related.Individuals presented similar genetic structure when the geographical distance between them was up to 56 m for FAPB and up to 156 m for FAPBA.It was concluded that anthropized environments exhibit less genetic diversity than native environments,inferring risks for species conservation if appropriate and planned management techniques are not adopted.展开更多
文摘The genetic diversity and population structure of the Dybowski＇s frog（Rana dybowskii） were investigated by using 11 polymorphic microsatellite loci.Total 75 individuals were sampled from six populations in Lesser Khingan Mountains and Changbai Mountains,China.Results showed that allele number of the 11 microsatellite loci was in the range of 2-10 in all populations,with the mean of 5.6.The average expected heterozygosity（HE） was 0.572,indicating a moderate polymorphism.The results of genetic differentiation coefficient（FST） showed that population genetic differentiation was significant between Changbai and Lesser Khingan Mountains（p〈0.001）.This result was verified further by Nei＇s genetic distance（DA） based on UPGMA phy-logenetic trees and by AMOVA analysis.In conclusion,the populations distributed in Lesser Khingan Mountains and Changbai Mountain are proposed to be two distinct management units（MUs） for their protection and management.
基金This work was supported financially by the Natural Science Foundation of China(No.31901099,31800350)Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration(No.SHUES2019B03)+2 种基金Science and Technology Commission of Shanghai Municipality(No.18DZ1205000)Institute of Eco-Chongming(No.ECNU-IEC-201902)Shanghai Landscaping and City Appearance Administrative Bureau(No.F131508).
文摘Amphibia ns play a key role in structuring biological assemblages of agricultural landscapes,but they are threatened by global agricultural intensification.Landscape structure is an important variable in flue ncing biodiversity in agricultural la ndscapes.However,in the Yangtze River Delta,where a"farmland-orchard-fishpond"agricultural pattern is common,the effects of landscape construction on anuran populations are unclear.In this study,we examined the effects of agricultural landscape parameters on the abundance and body condition of the rice frog(Fejervarya multistriata),which is a dominant anuran species in farmland in China.Employing a visual encounter method,we surveyed rice frog abundance for 3years across 20 agricultural landscapes.We also calculated the body condition index(BCD of 188 male frog individuals from these agricultural landscapes.Landscape variables,comprising landscape compositional heterogeneity(using the Shannon diversity in dex of all land cover types except buildings and roads),Ian dscape con figurational heterogeneity(using landscape edge density),breeding habitat diversity(using the number of 5 waterbody types available as breeding habitats),and areas of forest were also measured for each 1-km radius landscape.We found that the amount of forest in each agricultural Iandscape had a sign讦icant positive relationship with rice frog abundance,and breeding habitat diversity was positively related to the BCI of male rice frogs.However,body condition was negatively impacted by landscape configurational heterogeneity.Our results suggested the importance of nonagricultural habitats in agricultural landscapes,such as waterbodies and forest,to benefit rice frog population persistenee.
文摘An intelligent method of shifting cultivation to regenerate vegetation after a long fallow period is critical information for restoration strategies. The literature review identified that the assessment of woody plant species on abandoned farmland has never been done before in Kamwatta, Moruca Region 1. In addition, more information should be available in indigenous communities and at the national level, including more documentation of the utilization of natural resources by the Warrau community. This study assessed the valuable woody plant species that grew during the fallow periods. Nine farmlands were randomly selected along a 100 m transect, each with varying fallow periods. In order to collect information on the age of farm abandonment, the researcher employed a mixed-methods approach. First, we found how long each farm had been fallow by administering a semi-structured questionnaire. Then, we conducted a flora survey to gain information on the variety and abundance of valuable plants using the age of farm abandonment as a dependent variable. The data analysis included the number of valuable woody trees with a diameter of >10 cm, seedlings and saplings with a diameter of <10 cm, the location of identified trees, and the uses of identified tree species. Microsoft Excel was used to code and analyze the questionnaire, while QGIS, Shannon’s Index of Diversity, and Simple Linear Regression were used to analyze the inventory data. The results showed that the respondents listed 38 valuable woody species, and 79% occurred in the studied area. The field verification revealed that the dominant family in the area was Mimosaceae. Species abundance increased with fallow up to 10 years before declining in the latter years. Plant diversity and abundance had a weak relationship with the age of abandoned farmlands for woody trees, while the seedlings and saplings showed no relationship.
文摘In order to systematically study the diversity of plant communities in park green space,78 plant communities of 10 representative parks in Wuhan City were investigated.The total 449 species belonging to 275 genera and 112 families were found in this investigation.The communities were divided into 35 dominant-species,13 life-forms and 6 vegetation-forms.The community structures and the composition of dominant species were also studied.The results showed that the shortages of the low diversity,high proportion of exotic species and simple community structures appeared in plant community of park green space in Wuhan City.It is proposed that species,especially native ones,should be abundant to keep a high level species diversity.At the same time,more simulated native communities should be utilized to build the natural,multi-layers,bright local vegetation characteristics landscape of urban parks.
基金Acknowledgements We thank Feng XU and Yanping WANG for helping a part of field works and Richard Duncan for comments on the manuscript. This work was supported by a grant from National Science foundation （No. 30870312） and by a grant from the ＂973＂ program （No. 2007CB411600）.
文摘Native species may decline quickly when confronted with an exotic species to which they are not adapted. The extent of decline may depend on the abundance of an invader and the length of time since it first arrived in the community （residence time）, and the interaction between these two variables. We tested these effects using data on the effects of American bullfrog Lithobates catesbeianus invasion on native frog communities in 65 permanent lentic waters on islands in the Zhoushan Archipel- ago, China. We examined variation in native frog abundance and species richness in relation to features of the American bullfrog invasion, habitat disturbance, characteristics of the water body and fish communities and the presence of red swamp crayfish. Bullfrog invaded sites had lower native frog density and species richness, higher submerged vegetation cover and greater fre- quency of repairs to the water body than did non-invaded sites. The minimum adequate general linear mixed models showed that both native frog density and species richness were negatively related to post-metamorphosis bullfrog density, and that native frog species richness was also positively related to the vegetation cover. There was no effect on either native frog density or species richness of residence time or its interaction with bullfrog density, or of the abundance of bullfrog tadpoles. The results suggested that post-metamorphosis bullfrogs had impacts on native frog communities in the islands, and that the extents of these impacts are proportional to post-metamorphosis bullfrog density
文摘In the Indian Himalayan Region, th studies focused on diversity of the plants used fo treating liver diseases/ailments have not been carried out so far. Therefore, the present attempt has been made to study the diversity, distribution pattern and conservation status of the plant species used fo treating liver diseases/ailments in that region. A tota of 138 species (35 species of trees, 22 shrubs and 8 herbs) belonging to 98 genera in 60 families hav been recorded. Amongst the families, Euphorbiacea (9 species), and altitudinal zone <1,800 m, (i.e., 11 species) are rich in species. Traditionally, variou plant parts, such as roots/rhizomes/tubers (46 species), leaves (31), whole plants (30), barks (15) fruits (13), seeds and unspecified parts (8 each), and inflorescence (1) are used for the treatment of live diseases/ailments. 34 species are native, 3 ar endemic and 15 near endemic. 7 species ar categorized as Critically Endangered (Betula utilis) Endangered (Podophyllum hexandrum, Ephedra gerardiana, and Nardostachys grandiflora) and Vulnerable (Bergenia ligulata, B. stracheyi, and Hedychium spicatum) using new IUCN criteria Available chemical composition of plant parts used fo the treatment of liver diseases/ailments have beengiven. Assessment of the populations of threatened species, development of an appropriate strategy, action plan for the conservation and sustainable utilization of such components of plant diversity are suggested.
文摘The developmental activities, particularly the construction of hydroelectric projects are causing a great loss of biodiversity in the Indian Himalayan Region. The Himaehal Pradesh, a part of IHR is well known for the development of hydroelectric projects. The Parbati H.E. Project is amongst the major projects of the State. The different stages of the project are all causing loss of biodiversity of the area. Stage Ⅲ of the Parbati H.E. Project is a run of the river scheme on the Sainj River downstream of Power House of Parbati H.E. Project Stage Ⅱ. The project shall utilize regulated discharge of Parbati H.E. Project Stage Ⅱ and inflow of River Sainj for power generation, and has been contemplated as a peaking station operating in tandem with Stage Ⅱ. The present study has been undertaken to see the impact of hydroelectric project on the biodiversity, particularly on medicinal plants. A total of 104 species of medicinal plants, belonging to different life forms, i.e., trees （23 spp.）, shrubs （22 spp.）, herbs （57 spp.） and ferns （2 spp.） were recorded. The species have been analyzed and studied for their distribution, classification, altitudinal zones, part （s） used, indigenous uses, nativity, endemism and rarity.Different parts of these species, such as whole plants, roots （including rhizomes and tubers）, leaves, flowers, fruits, seeds, stems, barks, spikes, nuts and insect galls are used by the inhabitants for curing various diseases and ailments. 3o species are native to the Himalayan region, 9 species native to the Himalayan region and adjacent countries also and 65 species are non-natives. 9 species are near endemics. Considering the whole Himalaya as a biogeographie unit （sensu lato）, the near endemics are endemic to the Himalaya. Among these species, Zanthoxylum armature is categorized as Endangered and Valeriana wallichii as Vulnerable. Hedychium spicatum, Rhus javanica, Berberis lycium, Thalictrum foliolossum, Salvia lanata, Rubia cordifolia and Bergenia ligulata may be considered as threatened species due to their over exploitation for trade. 90 species are propagated by seeds, 8 species by seeds and rhizomes/roots/tubers, 4 species by seeds and cuttings, and 2 species by sori. A management plan for the cultivation and conservation of the medicinal plants in the dam submergence area, and the commercially viable medicinal plants with high value in the catchment area is suggested.
文摘In the Indian Himalayan Region predominantly rural in character, livestock is one of the main sources of livelihood and integral part of the economy. Livestock mostly rely on fodder from wild. The diversity, distribution, utilization pattern, nativity, endemism, rarity, seasonality of availability, nutritive values, perceived economic values and pressure use index of livestock have not been studied. The present study attempts to enumerate 150 species of fodder representing trees (51 spp.), shrubs (54 spp.) and herbs (45 spp.). Poaceae (19 spp.) and Fabaceae (13 spp.) amongst families and Salix (6 spp.), Ficus, Clematis, and Desmodium (5 spp., each) amongst genera are rich in species. Maximum species were found in the 1801 ~ 2600 m zone, and the remaining two zones showed relatively low diversity. Out of the 150 species, 109 are used in summer, 5 winter and 36 throughout year. During rainy season, mostly grasses are used as fodder. Only 83 species are native to the Himalayan region, one species, Strobilanthus atropuroureus is endemic and 35 species are near endemic. The nutritive values of the fodder species were reviewed, and economic values and status of the species were also assessed. The pressure use index of the species was calculated on the basis of cumulative values of the utilization pattern, altitudinal distribution, availability, status, nativity and endemism. Amongst the species, Grewia oppositifoilia, Morus serrata, Indigofera heterantha, Quercus leucotrichphora, Ulmus villosa, U. wallichiana and Aesculus indica showed highest PUI indicating high preference and pressure. Season wise prioritization of the species for different altitudinal zones has been done. Appropriate strategy and action plan have been suggested for the conservation and management of fodder species.
文摘Although the relationship between invasive alien species (IAS) and plant community structure has attracted considerable interest, the impacts of IAS on abundance and diversity of resident plant communities in species rich-ecosystems, such as tropical wetlands are poorly understood. Consequently, this has impeded development of improved management strategies and successful restoration of invaded tropical wetlands. Therefore, data on vegetation were collected from 60 plots of 20 × 50 m to study the impacts of alien invasive grass Echinochloa colona (L.) Link abundance on plant community abundance, richness, evenness and diversity of resident plant species within grasslands of the Kilombero Valley wetland, Tanzania. Moreover, the impacts of abundance of E. colona on plant functional groups (i.e. graminoids, forbs and shrubs) richness were also explored. Generalized linear models showed that community richness, evenness, diversity and abundance of resident species were negatively related to the E. colona abundance. There was a negative relationship between richness of graminoids and shrubs and the abundance of E. colona. Similarly, the abundance of graminoids, forbs and shrubs is related negatively to the abundance of E. colona. Given that most of the community and functional group attributes of resident plants is related negatively to E. colona abundance, improved management strategies should be developed to minimize the abundance and further spread of E. colona to restore and conserve wetland biodiversity.
基金funded by the Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq-National Council for Scientific and Technological Development-Grant 458151/2013-0)Instituto Chico Mendes de Conservacao da Biodiversidade (ICMBio-Chico Mendes Institute for Biodiversity Conservation) through financial aid and fellowships。
文摘The Brazilian state of Acre has an extensive natural reserve of bamboo,making it one of the largest in loco gene banks.The aim of this study was to characterize the structure and genetic diversity of Guadua weberbaueri Pilg.in two populations,one native(FAPB)and the other anthropized(FAPBA),using ISSR markers.The results show that the FAPB population exhibited higher values for all estimates of population diversity.However,the FAPBA population also showed high heterozygosity,corroborated by estimated gene flow(Nm=3.9)between the populations.The study of the association between Nei’s genetic distances and the geographic distances between the populations were significantly correlated(r=0.45,p=0.01),corroborated by the dendrogram revealing two distinct groups corresponding to the collection sites,without mixing classes between populations in the same group.As for the coancestry coefficient,pairs of individuals in the first distance class were positive and significant,indicating that plants that are geographically closer share common alleles with a frequency greater than by chance,which means that there is a tendency that geographically closer individuals are related.Individuals presented similar genetic structure when the geographical distance between them was up to 56 m for FAPB and up to 156 m for FAPBA.It was concluded that anthropized environments exhibit less genetic diversity than native environments,inferring risks for species conservation if appropriate and planned management techniques are not adopted.
