According to the survey of Guangdong mangrove resource in 2001 and authors field investigations in the past 5 years, the total mature mangrove land area of Guangdong Province was estimated at 9084 hm2, accounting for ...According to the survey of Guangdong mangrove resource in 2001 and authors field investigations in the past 5 years, the total mature mangrove land area of Guangdong Province was estimated at 9084 hm2, accounting for 41.4% of total mangrove land area of China. These mangrove forests totally consisted of 50 species belonging to 28 families, distributed at more than 100 locations along the coastlines of Guangdong and most of them present a high dense and dwarf appearance. The Ass. Avicennia marina is the most dominant mangrove association. The investigation results showed that the mangrove forests with coverage rates above 0.7 accounted for 68.0% of the total mangrove land area of the province and 77.8% of mangrove forests was less than 2 m in tree height. Since 1950, 54.6% of mangrove forests have disappeared due to paddy rice reclaim, aquaculture and city constructions. Derivational conservation efforts are still weakly empowered and should be strengthened intensively. The author suggested that mangrove laws and regulations should be enforced, mangrove scientific research should be strengthened; and mangrove conservation awareness of local community should be raised on conservation of mangroves.展开更多
Photo-protective functions were investigated in phytoplankton assemblages at Kongsfjorden, Svalbard in spring, using their UV-absorbing compounds （mycosporine-like amino acids （MAAs））, xanthophyllpigments （diadin...Photo-protective functions were investigated in phytoplankton assemblages at Kongsfjorden, Svalbard in spring, using their UV-absorbing compounds （mycosporine-like amino acids （MAAs））, xanthophyllpigments （diadinoxanthin （DD） and diatoxanthin （DT）） and〈beta〉-dimethylsulphoniopropionate （〈beta〉-DMSP）. The dominant phytoplankton species in the inner bay were dominated by Phaeocystis spp. and nanoflagellates, while the offshore waters were dominated by Thalassiosira spp. In the inner bay, UV- absorbing compounds and xanthophyll pigments exhibited higher ratios of MAA to chlorophyll a （MAA：chl a ratio）, and both DD and DT to chlorophyll a （DD：chl a ratio and DT：chl a ratio）, respectively. Thus, the photoprotective-pigrnents such as DD and DT appear to complement MAAs in the natural phytoplankton assemblage. However, the ratio of 〈beta〉-DMSP to chlorophyll a （〈beta〉-DMSP：chl a ratio） did not show a distinct spatial distribution according to environmental factors or interspecies differences. In this study, we found that photoprotective compounds occurred in a manner dependent on the phytoplankton species composition in Kongsfjorden Bay, where Phaeocystis is the dominant species.展开更多
Seagrass habitats are structurally complex ecosystems, which support high productivity and biodiversity. In temperate systems the density of seagrass may change seasonally, and this may influence the associated fish a...Seagrass habitats are structurally complex ecosystems, which support high productivity and biodiversity. In temperate systems the density of seagrass may change seasonally, and this may influence the associated fish and invertebrate community. Little is known about the role of seagrass beds as possible nursery areas for fish and invertebrates in China. To study the functioning of a seagrass habitat in northern China, demersal fish and invertebrates were collected monthly using traps, from February 2009 to January 2010. The density, leaf length and biomass of the dominant seagrass Zostera marina and water temperature were also measured. The study was conducted in a Seagrass Natural Reserve(SNR) on the eastern coast of the Shandong Peninsula, China. A total of 22 fish species and five invertebrate species were recorded over the year. The dominant fish species were Synechogobius ommaturus, Sebastes schlegelii, Pholis fangi, Pagrus major and Hexagrammos otakii and these species accounted for 87% of the total number of fish. The dominant invertebrate species were Charybdis japonica and Octopus variabilis and these accounted for 98% of the total abundance of invertebrates. There was high temporal variation in species composition and abundance. The peak number of fish species occurred in August–October 2009, while the number of individual fish and biomass was highest during November 2009. Invertebrate numbers and biomass was highest in March, April, July and September 2009. Temporal changes in species abundance of fishes and invertebrates corresponded with changes in the shoot density and leaf length of the seagrass, Zostera marina.展开更多
The description and understanding of plant communities is fundamental for the implementation of conservation or restoration programs, especially when these communities are highly threatened and need to be restored.Cam...The description and understanding of plant communities is fundamental for the implementation of conservation or restoration programs, especially when these communities are highly threatened and need to be restored.Campos rupestres, some Neotropical mountain grasslands located in central Brazil and part of the Cerrado biome(covering 2 million km2) host unique plant communities, currently threatened by quarrying and mining.The grassy matrix of campos rupestres, has long been considered a rich mosaic under the control of local topography and the nature of substrate, but this affirmation has not been well studied.We analyzed whether plant communities varied in relation to edaphic factors within the stony substrate and the sandy substrate of this grassy matrix.We selected 5 sites where occur both grasslands on stony substrate and on sandy substrate, and we carried out vegetation surveys and soil analyses.We counted 222 plant species within our communities, among which38.6% are exclusively found on campos rupestres.Our results show that both soil-types are strongly acidic, nutrient poor and exhibit a seasonal variation.Phosphorus increases and p H and organic carbon decrease during the dry season.Stony soils areslightly richer in nutrients than sandy soils and differences in soil granulometry and composition have led to the formation of distinct plant communities.Some species are confined to either one or the other grassland-type, which makes the plant composition of each community unique.Variations in edaphic factors generate heterogeneous grasslands favorable to a high plant diversity.Conservation programs and restoration actions have to maintain or recreate this heterogeneity.The presence of distinct plant communities implies that different strategies might be adopted to improve the restoration of these ecosystems.展开更多
Different types of vegetation occupy different geomorphology and water gradient environments in the San- jiang Plain, indicating that the soil moisture dynamics and water balance patterns of the different vegetation c...Different types of vegetation occupy different geomorphology and water gradient environments in the San- jiang Plain, indicating that the soil moisture dynamics and water balance patterns of the different vegetation communi- ties might differ from each other. In this paper, a lowland system, perpendicular to the Nongjiang River in the Honghe National Nature Reserve （HNNR）, was selected as the study area. The area was occupied by the non-wetland plant forest and the typical wetland plant meadow. The Microsoft Windows-based finite element analysis software package for simulating water, heat, and solute transport in variably saturated porous media （HYDRUS）, which can quantita- tively simulate water, heat, and/or solute movement in variably-saturated porous media, was used to simulate soil moisture dynamics in the root zone （20-40 cm） of those two plant communities during the growing season in 2005. The simulation results for soil moisture were in a good agreement with measured data, with the coefficient of determi- nation （R2） of 0.44-0.69 and root mean square error （RMSE） ranging between 0.0291 cm3/cm3 and 0.0457 cm3/cm3, and index of agreement （d） being from I）.612 to 0.968. During the study period, the volumetric soil moisture content of meadow increased with the depth and its coefficient of variation decreased with the depth （from 20 cm to 40 cm）, while under the forest the soil moisture content at different depths varied irregularly. The calculated result of water budget showed that the water budget deficit of the meadow was higher than that of the forest, suggesting that the meadow is more likely to suffer from water stress than the forest. The quantitative simulation by HYDRUS in this study did not take surface runoff and plant growth processes into account. Improved root water uptake and surface runoff models will be needed for higher accuracy in further researches.展开更多
Present study has been conducted in a biodiversity rich Nanda Devi Biosphere Reserve between 2000-3800 m in two different forest physiognomy holding sites to analyze the structure and composition of the forest communi...Present study has been conducted in a biodiversity rich Nanda Devi Biosphere Reserve between 2000-3800 m in two different forest physiognomy holding sites to analyze the structure and composition of the forest communities including richness of native, non native and endemic species,and suggest conservation values at community and reserve level.A total of 60 sites were sampled and grouped in 11 and 8 communities for two representative sites Pindari-Sunderdhunga-Kafni(PSK) and Lata-Tolma-Phagti(LTP) respectively.From the sampled sites, 451 species(11.8%, 53 trees;17.71%, 80 shrubs; and 70.51%, 318 herbs) have been recorded.In general, PSK site represented 73.6% and LTP site represented only 54.9% of the total plant species recorded in the study area.Out of total species in PSK site, native species contributed 59.6%(198spp.) and 24.7% species were endemic and near endemic.In LTP site, 66.5% species were Himalayan natives and 33.5% were endemic and near endemic.The species richness ranged from 4-23 ind ha-1(tree),3-18 ind ha-1(sapling), 5-19 ind ha-1(seedling) in PSK site and 4-18 ind ha-1(tree), 4-11 ind ha-1(sapling), 4-16 ind ha-1(seedling) in LTP site.The density ranged from 260-535 ind ha-1(tree), 145-633 ind ha-1(sapling), 1450-8170 ind ha-1(seedling) in PSK site and 599-1211 ind ha-1(tree), 70-951 ind ha-1(sapling),470-1665 ind ha-1(seedling) in LTP site.Species diversity for trees ranged from 0.73-3.37, saplings,0.64-2.67, seedlings, 0.70-2.51, shrubs, 1-2.34 and herbs, 2.02-3.21 in PSK site and 0.63-1.61, saplings,0.76-1.36, seedlings, 0.35-1.79, shrubs, 0.98-2.73 and herbs, 2.48-3.61 in LTP site.These recorded values were almost comparable with the studies conducted in sub-tropical, temperate and sub-alpine regions of the west Himalaya.In some cases the values were slightly higher than the reported values.The important communities with high conservation values have been identified based on different ecological parameters and species distribution.Among all the prioritized communities, Mixed Silver firRhododendron-Maple community in PSK site and Taxus wallichana- A.pindrow mixed community in LTP site supports maximum richness and density of native and endemic species.This study calls for development of adequate strategy and action plan for the conservation and management of habitats, species,and communities under changing climate and socioeconomic scenarios, so that sustainable utilization of the species could be ensured.展开更多
Understanding the response of understory vegetation to fire disturbance is vital to biodiversity conservation and management of boreal forests. We surveyed understory vascular plant richness and composition, and measu...Understanding the response of understory vegetation to fire disturbance is vital to biodiversity conservation and management of boreal forests. We surveyed understory vascular plant richness and composition, and measured related environmental variables along a toposequence within three successional stages, initial （3 years post-fire）, early （13 years post-fire） and late （〉1oo years post-fire） successional stages. Using permutation multivariate ANOVA and nonmetric multidimensional scaling, we analyzed how understory species richness and composition change as time-since-fire proceeds, and their correlative relationships with environmental variables. Species richness and composition showed significant differences among the three successional stages. Understory species richness and abundance were significantly associated with time-since-fire, topographic position, elevation and organic layer depth. Among these variables, time-since-fire had the strongest effect and topographic position was the second major factor on affecting understorycommunity assembly. In overwhelmed the effects addition, time-since-fire of soil pH in the initial successional stage and gravimetric soil moisture in early and late successional stages on understory species composition展开更多
文摘According to the survey of Guangdong mangrove resource in 2001 and authors field investigations in the past 5 years, the total mature mangrove land area of Guangdong Province was estimated at 9084 hm2, accounting for 41.4% of total mangrove land area of China. These mangrove forests totally consisted of 50 species belonging to 28 families, distributed at more than 100 locations along the coastlines of Guangdong and most of them present a high dense and dwarf appearance. The Ass. Avicennia marina is the most dominant mangrove association. The investigation results showed that the mangrove forests with coverage rates above 0.7 accounted for 68.0% of the total mangrove land area of the province and 77.8% of mangrove forests was less than 2 m in tree height. Since 1950, 54.6% of mangrove forests have disappeared due to paddy rice reclaim, aquaculture and city constructions. Derivational conservation efforts are still weakly empowered and should be strengthened intensively. The author suggested that mangrove laws and regulations should be enforced, mangrove scientific research should be strengthened; and mangrove conservation awareness of local community should be raised on conservation of mangroves.
基金Supported by the Korea-Polar Ocean in Rapid Transition by the Ministry of Oceans and Fisheries,Korea(KOPRI,No.PM14040)
文摘Photo-protective functions were investigated in phytoplankton assemblages at Kongsfjorden, Svalbard in spring, using their UV-absorbing compounds （mycosporine-like amino acids （MAAs））, xanthophyllpigments （diadinoxanthin （DD） and diatoxanthin （DT）） and〈beta〉-dimethylsulphoniopropionate （〈beta〉-DMSP）. The dominant phytoplankton species in the inner bay were dominated by Phaeocystis spp. and nanoflagellates, while the offshore waters were dominated by Thalassiosira spp. In the inner bay, UV- absorbing compounds and xanthophyll pigments exhibited higher ratios of MAA to chlorophyll a （MAA：chl a ratio）, and both DD and DT to chlorophyll a （DD：chl a ratio and DT：chl a ratio）, respectively. Thus, the photoprotective-pigrnents such as DD and DT appear to complement MAAs in the natural phytoplankton assemblage. However, the ratio of 〈beta〉-DMSP to chlorophyll a （〈beta〉-DMSP：chl a ratio） did not show a distinct spatial distribution according to environmental factors or interspecies differences. In this study, we found that photoprotective compounds occurred in a manner dependent on the phytoplankton species composition in Kongsfjorden Bay, where Phaeocystis is the dominant species.
基金Supported by the National Basic Research Program of China(973 Program)(No.2015CB453303)the National Special Research Fund for Non-Profit Marine Sector(No.201405010-2)the Science and Technology Development Program of Shandong(No.2014GSF117003)
文摘Seagrass habitats are structurally complex ecosystems, which support high productivity and biodiversity. In temperate systems the density of seagrass may change seasonally, and this may influence the associated fish and invertebrate community. Little is known about the role of seagrass beds as possible nursery areas for fish and invertebrates in China. To study the functioning of a seagrass habitat in northern China, demersal fish and invertebrates were collected monthly using traps, from February 2009 to January 2010. The density, leaf length and biomass of the dominant seagrass Zostera marina and water temperature were also measured. The study was conducted in a Seagrass Natural Reserve(SNR) on the eastern coast of the Shandong Peninsula, China. A total of 22 fish species and five invertebrate species were recorded over the year. The dominant fish species were Synechogobius ommaturus, Sebastes schlegelii, Pholis fangi, Pagrus major and Hexagrammos otakii and these species accounted for 87% of the total number of fish. The dominant invertebrate species were Charybdis japonica and Octopus variabilis and these accounted for 98% of the total abundance of invertebrates. There was high temporal variation in species composition and abundance. The peak number of fish species occurred in August–October 2009, while the number of individual fish and biomass was highest during November 2009. Invertebrate numbers and biomass was highest in March, April, July and September 2009. Temporal changes in species abundance of fishes and invertebrates corresponded with changes in the shoot density and leaf length of the seagrass, Zostera marina.
文摘The description and understanding of plant communities is fundamental for the implementation of conservation or restoration programs, especially when these communities are highly threatened and need to be restored.Campos rupestres, some Neotropical mountain grasslands located in central Brazil and part of the Cerrado biome(covering 2 million km2) host unique plant communities, currently threatened by quarrying and mining.The grassy matrix of campos rupestres, has long been considered a rich mosaic under the control of local topography and the nature of substrate, but this affirmation has not been well studied.We analyzed whether plant communities varied in relation to edaphic factors within the stony substrate and the sandy substrate of this grassy matrix.We selected 5 sites where occur both grasslands on stony substrate and on sandy substrate, and we carried out vegetation surveys and soil analyses.We counted 222 plant species within our communities, among which38.6% are exclusively found on campos rupestres.Our results show that both soil-types are strongly acidic, nutrient poor and exhibit a seasonal variation.Phosphorus increases and p H and organic carbon decrease during the dry season.Stony soils areslightly richer in nutrients than sandy soils and differences in soil granulometry and composition have led to the formation of distinct plant communities.Some species are confined to either one or the other grassland-type, which makes the plant composition of each community unique.Variations in edaphic factors generate heterogeneous grasslands favorable to a high plant diversity.Conservation programs and restoration actions have to maintain or recreate this heterogeneity.The presence of distinct plant communities implies that different strategies might be adopted to improve the restoration of these ecosystems.
基金Under the auspices of National Natural Science Foundation of China (No. 40871241,41001050)Direction Project of Chinese Academy of Science (KZCX2-YW-Q06-03)
文摘Different types of vegetation occupy different geomorphology and water gradient environments in the San- jiang Plain, indicating that the soil moisture dynamics and water balance patterns of the different vegetation communi- ties might differ from each other. In this paper, a lowland system, perpendicular to the Nongjiang River in the Honghe National Nature Reserve （HNNR）, was selected as the study area. The area was occupied by the non-wetland plant forest and the typical wetland plant meadow. The Microsoft Windows-based finite element analysis software package for simulating water, heat, and solute transport in variably saturated porous media （HYDRUS）, which can quantita- tively simulate water, heat, and/or solute movement in variably-saturated porous media, was used to simulate soil moisture dynamics in the root zone （20-40 cm） of those two plant communities during the growing season in 2005. The simulation results for soil moisture were in a good agreement with measured data, with the coefficient of determi- nation （R2） of 0.44-0.69 and root mean square error （RMSE） ranging between 0.0291 cm3/cm3 and 0.0457 cm3/cm3, and index of agreement （d） being from I）.612 to 0.968. During the study period, the volumetric soil moisture content of meadow increased with the depth and its coefficient of variation decreased with the depth （from 20 cm to 40 cm）, while under the forest the soil moisture content at different depths varied irregularly. The calculated result of water budget showed that the water budget deficit of the meadow was higher than that of the forest, suggesting that the meadow is more likely to suffer from water stress than the forest. The quantitative simulation by HYDRUS in this study did not take surface runoff and plant growth processes into account. Improved root water uptake and surface runoff models will be needed for higher accuracy in further researches.
基金In-House Project-08(2007-2012)DST(SB/YS/LS-205/2013)+1 种基金CSIR(09/560(0015)/2011-EMRI)Govt.of India
文摘Present study has been conducted in a biodiversity rich Nanda Devi Biosphere Reserve between 2000-3800 m in two different forest physiognomy holding sites to analyze the structure and composition of the forest communities including richness of native, non native and endemic species,and suggest conservation values at community and reserve level.A total of 60 sites were sampled and grouped in 11 and 8 communities for two representative sites Pindari-Sunderdhunga-Kafni(PSK) and Lata-Tolma-Phagti(LTP) respectively.From the sampled sites, 451 species(11.8%, 53 trees;17.71%, 80 shrubs; and 70.51%, 318 herbs) have been recorded.In general, PSK site represented 73.6% and LTP site represented only 54.9% of the total plant species recorded in the study area.Out of total species in PSK site, native species contributed 59.6%(198spp.) and 24.7% species were endemic and near endemic.In LTP site, 66.5% species were Himalayan natives and 33.5% were endemic and near endemic.The species richness ranged from 4-23 ind ha-1(tree),3-18 ind ha-1(sapling), 5-19 ind ha-1(seedling) in PSK site and 4-18 ind ha-1(tree), 4-11 ind ha-1(sapling), 4-16 ind ha-1(seedling) in LTP site.The density ranged from 260-535 ind ha-1(tree), 145-633 ind ha-1(sapling), 1450-8170 ind ha-1(seedling) in PSK site and 599-1211 ind ha-1(tree), 70-951 ind ha-1(sapling),470-1665 ind ha-1(seedling) in LTP site.Species diversity for trees ranged from 0.73-3.37, saplings,0.64-2.67, seedlings, 0.70-2.51, shrubs, 1-2.34 and herbs, 2.02-3.21 in PSK site and 0.63-1.61, saplings,0.76-1.36, seedlings, 0.35-1.79, shrubs, 0.98-2.73 and herbs, 2.48-3.61 in LTP site.These recorded values were almost comparable with the studies conducted in sub-tropical, temperate and sub-alpine regions of the west Himalaya.In some cases the values were slightly higher than the reported values.The important communities with high conservation values have been identified based on different ecological parameters and species distribution.Among all the prioritized communities, Mixed Silver firRhododendron-Maple community in PSK site and Taxus wallichana- A.pindrow mixed community in LTP site supports maximum richness and density of native and endemic species.This study calls for development of adequate strategy and action plan for the conservation and management of habitats, species,and communities under changing climate and socioeconomic scenarios, so that sustainable utilization of the species could be ensured.
基金funded by the National Natural Science Foundation of China (Grant Nos. 31270511, 41501200)
文摘Understanding the response of understory vegetation to fire disturbance is vital to biodiversity conservation and management of boreal forests. We surveyed understory vascular plant richness and composition, and measured related environmental variables along a toposequence within three successional stages, initial （3 years post-fire）, early （13 years post-fire） and late （〉1oo years post-fire） successional stages. Using permutation multivariate ANOVA and nonmetric multidimensional scaling, we analyzed how understory species richness and composition change as time-since-fire proceeds, and their correlative relationships with environmental variables. Species richness and composition showed significant differences among the three successional stages. Understory species richness and abundance were significantly associated with time-since-fire, topographic position, elevation and organic layer depth. Among these variables, time-since-fire had the strongest effect and topographic position was the second major factor on affecting understorycommunity assembly. In overwhelmed the effects addition, time-since-fire of soil pH in the initial successional stage and gravimetric soil moisture in early and late successional stages on understory species composition
