[Objective] The aim was to explore the management mode on optimal re-sources al ocation of family ranch in meadow steppe. [Method] Three double repre-sentative family ranches were selected in meadow steppe of Hulunber...[Objective] The aim was to explore the management mode on optimal re-sources al ocation of family ranch in meadow steppe. [Method] Three double repre-sentative family ranches were selected in meadow steppe of Hulunber Old Barag Banner, and the study was carried out with the baseline survey. Three family ranches were selected as the demonstrative households for the corporation study, while other three family ranches with the similar conditions were looked as the non-demonstrative households for the comparison. Demonstrative households of the fami-ly ranches reduced the stocking rate, optimized the flock structure and took a winter feeding and other means to explore the different management models on plant com-munity characteristic of family ranch. [Result] The seasonal dynamic of community characteristic in family ranches showed the single-peaks curves. The seasonal dy-namics of community coverage, height and biomass in the demonstrative households showed higher compared with the non-demonstrative households, and community density in the experiment households was lower than that of the control experiment households. Community coverage, height and biomass of degraded grassland in family ranch have a great improve after optimization of management. Community coverage, height , density and biomass were increasing in fencing plot, but decreas-ing in free grazing area. Enclosure improved grassland coverage, vegetation height, density and forage yield. Leymus chinensis played an important role in plant com-munity. The important values of Leymus chinensis, Stipa baicalensis, Cleistogenes squarrosa, and Carex duriuscula were high. Leymus chinensis important value in the demonstrative households of optimal management was higher than that in the non-demonstrative households, and Carex duriuscula important value of the non-demon-strative households was significantly higher than that of the demonstrative house-holds. The indexes of Margalef richnes,Shannon-Wiener diversity, Simpson diversity and Pielou uniformity showed that the demonstrative households were higher than the non-demonstrative households. [Conclusion] The research provides theoretical ref-erences for sustainable development of pastures dominated by family ranch.展开更多
Biologically active carbon (BAC) system was set up in a water plant of South China during January to December 2007,to study the invertebrate community characteristics of BAC filter.Thirty-seven invertebrate species ...Biologically active carbon (BAC) system was set up in a water plant of South China during January to December 2007,to study the invertebrate community characteristics of BAC filter.Thirty-seven invertebrate species were found,of which 28 belonging to rotifers.Filter operation could lead to an output of invertebrates in high abundances with the filtrate,and the maximum density could reach 5608 individuals/m 3.Average abundances in the effluent water increased in 27-33 folds in comparison to the influent water during the sampling period.Invertebrate community succession had the following trend:filter-feeding animals → small benthic invertebrates → large benthic and resistant invertebrates.Abundances of large-sized invertebrates (copepod adult and oligochaete) at bigger-media column were significantly higher than that at small-media column.The results implied the abundant species diversity of invertebrate in BAC filter.The relationship between invertebrate and biofilm still remain to be studied in detail.展开更多
The Paper is the succession of the study on abundance distribution of planktonic copepods in the waters north of Taiwan, and the emphasis is laid on the analysis and discussion of the constructions and features of cop...The Paper is the succession of the study on abundance distribution of planktonic copepods in the waters north of Taiwan, and the emphasis is laid on the analysis and discussion of the constructions and features of copepod community and the relationships with water environment. The results show as follows: a total of 237 species were identified and the construction of communtity was complex. The percentage of annual present species was only 32%. The mean values of diversity and homogeneity of the copepod community were 3. 714 and 0. 690 respectively, and their horizontal distribution patterns were higher in outshore area than in nearshore area. The copepods of the area could be divided into five ectotypes. Warm-water outshore high temperature and lower saline group and tropic oceanic high temperature and saline group could indicate the seasonal changes of the Taiwan Strait water and the Kuroshio surface water respectively. According to the various aspects of calculation and analysis, winter was different from other three seasons in environmental conditions. In spring, summer and autumn, Undinula valgaris was the meat dominant species and salinity was the main factor that affected the community feature values. The communities in the three seasons had the subtropic-tropic characteristics in which warm-water outshore species were dominant and tropic oceanic species accounted for also certain proportion. While in winter, the dominant species was Euchaeta manna and temperature was the main factor influencing the community feture values. The community had the tropic oceanic characteristics in which tropic oceanic species were dominant.展开更多
The change of plant community character during recovery succession processes of high mountain meadow in Naqu, Tibet, was investigated. The results show that there are 41 plant species in the inventoried quadrates. The...The change of plant community character during recovery succession processes of high mountain meadow in Naqu, Tibet, was investigated. The results show that there are 41 plant species in the inventoried quadrates. The high-plants in four big families plays important roles in natural vegetation recovery, while Kobresia play an important role in climax communities. The plant species components changed with each succession stage. The plant species were mainly annual and biennial during the early succession stage, and perennial during the medium; and dominated by Kobresia humilis during the late. Potentilla bifurca and Potentilla tanaletfolia were both found in all stages. The accumulated number of family, genus, and species during the succession process varied quadric with the stages. The main plant community characteristics varied logistically with the succession stages except the height. The community characteristics mainly affected by dominant species which were changed in same rhythms. The biomass under ground was far more than the upground. The plant diversity inflated in the medium stage.展开更多
As a typical inland wetland, Yangguan nature reserve wetland in Dunhuang is one of the important stops of migratory route for birds, which is vulnerable and particular. Study on the community characteristics and speci...As a typical inland wetland, Yangguan nature reserve wetland in Dunhuang is one of the important stops of migratory route for birds, which is vulnerable and particular. Study on the community characteristics and species diversity of wetland has great signifi cance for biodiversity protection. Based on the fi eld investigation, the fl oristic composition, geographical elements and species diversity of wetland plants were studied in Yangguan reserve of Dunhuang. The results showed that 26 families, 56 genera and 74 species were recorded in the study area. The largest families were the Gramineae and Chenopodiaceae, accounting for 29.73% of the total. Herbs were the most abundant life-form, accounting for 77.03% of the total. The fl oral geographical elements of the plants were mainly composed of temperate zone distribution type. By using two way indicator species analysis(TWINSPAN), the vegetation in 36 sampling plots could be classifi ed into 8 communities. The species diversity indexes of communities were relatively low, but had large differences among each other. According to the importance value, the Margalef richness index(Rm) ranged from 0 to 4.200. Simpson diversity index(D) was between 0 and 0.512; Shannon diversity index(H) ranged from 0 to 1.400, and Pielou evenness index(J) was within the range of 0.538 to 1.000. The results indicated that the plant species were relatively rare and simple in general, the species diversity of communities was low, and the ecological environment was fragile in Yangguan nature reserve of Dunhuang.展开更多
In order to understand the biological community characteristics of different surface treatments of 'artificial reef templates ,which had been placed on the offshore, Yuanzhou island, Daya Bay. Sampling survey was tak...In order to understand the biological community characteristics of different surface treatments of 'artificial reef templates ,which had been placed on the offshore, Yuanzhou island, Daya Bay. Sampling survey was taken in August of 2014. The results showed that 39 species of fouling organisms were collected and iden- tiffed, Ostrea nigromarginata has attached the absolute position of the dominant species ; Through the concrete block surface treatment has a better biofouling effect, and red brick, granite plates and no-surface-treated concrete template attached biomass and abundance of organisms were very low ; Biomass and abundance indices and ecological indices do not show a certain degree of regularity.展开更多
[Objectives]This study was conducted to analyze species composition, community appearance, plant life-type spectrum, flora distribution, plant community structure and plant diversity indexes of Mingyue Park in Jingzho...[Objectives]This study was conducted to analyze species composition, community appearance, plant life-type spectrum, flora distribution, plant community structure and plant diversity indexes of Mingyue Park in Jingzhou City, as well as the ecological functions of plants in cooling, humidification, shading, and noise reduction. [Methods] A quadart method was used to investigate plant communitues of Mingyue Park in Jingzhou City. [Results] There were 141 species in the park, including 44 tree speceies, 35 shrub speceies, and 62 herb speceies. The arber-shrub-grass structure was the dominant plant community structure. The Simpson index(D), Shannon-Wiener index(H) and Pielou index(J) of the herb layer were higher than those of the tree layer and the shrub layer, and the shrub layer was the lowest. The results of ecological function research showed that the plant communities had a significant shading effect and a certain ability to reduce noise. The comprehensive conclusion showed that the ecological function indexes of the arbor-shrub-grass structure in Mingyue Park were significantly higher than those of the arbor-shrub structure and the single-tree structure. In order to improve the ecological benefits of plant communities in Mingyue Park, the plant diversity can be increased in the later construction to enrich community structures. [Conclusions] This study evaluated the ecological benefits of plant communities in Mingyue Park, and provides a scientific basis for the plant configuration of parks in Jingzhou and other regions.展开更多
In this paper,the geographical distribution,community characteristics and DBH class structure of Picea neoveitchii Mast. population were investigated and analyzed by systematical and ecological approaches. In addition...In this paper,the geographical distribution,community characteristics and DBH class structure of Picea neoveitchii Mast. population were investigated and analyzed by systematical and ecological approaches. In addition,the endangered mechanism and the protection measures were put forward by analyzing the Picea neoveitchii Mast. resource distribution in Hubei Province to provide effective scientific basis for further research. The results showed that Picea neoveitchii Mast. was found in Baokang,Enshi,Shennongjia and Zhuxi of Hubei Province,there were 9 distribution points and only a wild forest was found in Baokang. The community of Baokang County was not rich in species composition and 32 species,29 genera and 21 families were examined. Meanwhile,temperate zone was the main flora element of this community,the phaenerophytes plant was most dominant and there were few hemicryptophytes and it lacked therophytes. In this community,Picea neoveitchii Mast. was in a dominant position,including lots of treelets,so the age structure of the population was growing.展开更多
Soil erosion caused by unsustainable grazing is a major driver of grassland ecosystem degradation in many semi-arid hilly areas in China.Thus,grazing exclusion is considered as an effective method for solving this iss...Soil erosion caused by unsustainable grazing is a major driver of grassland ecosystem degradation in many semi-arid hilly areas in China.Thus,grazing exclusion is considered as an effective method for solving this issue in such areas.However,some ecological and economic problems,such as slow grassland rejuvenation and limited economic conditions,have become obstacles for the sustainable utilization of grassland ecosystem.Accordingly,we hypothesized that the conflict between grassland use and soil conservation may be balanced by a reasonable grazing intensity.In this study,a two-year grazing fence experiment with five grazing intensity gradients was conducted in a typical grassland of the Loess Plateau in China to evaluate the responses of vegetation characteristics and soil and water losses to grazing intensity.The five grazing intensity gradients were 2.2,3.0,4.2,6.7,and 16.7 goats/hm2,which were represented by G1-G5,respectively,and no grazing was used as control.The results showed that a reasonable grazing intensity was conducive to the sustainable utilization of grassland resources.Vegetation biomass under G1-G4 grazing intensity significantly increased by 51.9%,42.1%,36.9%,and 36.7%,respectively,compared with control.In addition,vegetation coverage increased by 19.6%under G1 grazing intensity.Species diversity showed a single peak trend with increasing grazing intensity.The Shannon-Wiener diversity index under G1-G4 grazing intensities significantly increased by 22.8%,22.5%,13.3%,and 8.3%,respectively,compared with control.Furthermore,grazing increased the risk of soil erosion.Compared with control,runoff yields under G1-G5 grazing intensities increased by 1.4,2.6,2.8,4.3,and 3.9 times,respectively,and sediment yields under G1-G5 grazing intensities were 3.0,13.0,20.8,34.3,and 37.7 times greater,respectively,than those under control.This result was mainly attributed to a visible decrease in litter biomass after grazing,which decreased by 50.5%,72.6%,79.0%,80.0%,and 76.9%,respectively,under G1-G5 grazing intensities.By weighing the grassland productivity and soil conservation function,we found that both two aims were achieved at a low grazing intensity of less than 3.5 goats/hm2.Therefore,it is recommended that grassland should be moderately utilized with grazing intensity below 3.5 goats/hm2 in semi-arid hilly areas to achieve the dual goals of ecological and economic benefits.The results provide a scientific basis for grassland utilization and health management in semi-arid hilly areas from the perspective of determining reasonable grazing intensity to maintain both grassland production and soil conservation functions.展开更多
The macrobenthic community of the Xiaoqing River Estuary and the adjacent sea waters was investigated in May and November 2008,August 2009,and May and September 2010,respectively.A total of 95 species of macrobenthos ...The macrobenthic community of the Xiaoqing River Estuary and the adjacent sea waters was investigated in May and November 2008,August 2009,and May and September 2010,respectively.A total of 95 species of macrobenthos were identified in the five cruises and most of them were polychaetes(46.39%),mollusks(28.86%) and crustaceans(20.62%).The Shannon-Wiener index of macrobenthos was lower than 2 in 67% sites.Along the stream channel,estuary and the coastal waters,the species of polychaetes reduced gradually,while the abundance increased at first and then decreased.The abundance was the biggest at regions with salinity of 5 20 in the estuary.The species and abundance of mollusks and crustaceans increased gradually.As for seasonal distribution,the species,abundance and biomass were higher in spring and lower in summer and autumn.Contemporaneously compared with Laizhou Bay and Yellow River Estuary,the species of macrobenthos appeared in the Xiaoqing River Estuary were much less,while the percentage of polychaetes was higher.Abundance and biomass were higher in Xiaoqing River estuary,then consequently followed by Laizhou Bay and Yellow River Estuary.The dominant species in Xiaoqing River Estuary was polychaete,and Layzhou Bay mollusk.The community structure characteristics of macrobenthos in the Xiaoqing River Estuary revealed a significant pollution status in this region.展开更多
The paper analyzes the hypothesis that the distribution of dominant plant species and characteristics of plant communities are related to groundwater depth. The results showed that variations of groundwater depth impa...The paper analyzes the hypothesis that the distribution of dominant plant species and characteristics of plant communities are related to groundwater depth. The results showed that variations of groundwater depth impacted distributions and characteristics of dominant plant communities. However, besides groundwater depth, the community composition and species diversity were also influenced by physiognomy of the habitat. Based on the similarity coefficient, the differences between dominant plant communities were significant at different groundwater depths. Compared with other results relating to desert vegetation and groundwater depth, variations of community distribution were similar at the large spatial scale. However, in this extremely arid region, there were significant differences in community type and community succession when compared with other arid regions, especially in relationship to deep groundwater depth. With groundwater depth from deep to shallow, communities transformed with the sequence of Alhagi communities, Tamarix spp. communities, Populus communities, Phragmites communities, and Sophora communities. At groundwater depth of less than 6.0 m, the community type and composition changed, and the species diversity increased. Among these dominant species, Tamarix exhibited the biggest efficiency in resource utilization according to niche breadth, which means it possessed the best adaptability to environmental conditions at the oasis margins.展开更多
[ Objective ] The paper was to understand the characteristics of plant communities in three kinds of typical alpine meadows in Haibei Region, Qinghai Province. [ Method] The characteristics and diversity of plant comm...[ Objective ] The paper was to understand the characteristics of plant communities in three kinds of typical alpine meadows in Haibei Region, Qinghai Province. [ Method] The characteristics and diversity of plant communities in typical alpine meadow, including Kobresia humilis, PotentiUafruticose and Kobresia menyuanica, were studied, with Menyuan studfarm in Haibei region of Qinghai Province as an example. [ Result] Results showed that the three kinds of plant communities in alpine meadows presented complex structure; the diversity index had close relationship with the evenness index; there were fewer common species and higher species replacement rate among different alpine meadow communities ; the aboveground biomass of K. humilis alpine meadow was 1.62 and 1.69 times of P. fruticose and K. menyuanica meadows, respectively; the underground biomass mainly distributed in the 0 - 10 cm soil layer, and the vertical spatial distribution structure was "T" type; the aboveground and underground biomass were negatively correlated. [ Conclusion] The paper will provide basis for protection and further use of different grassland plant communities in Haibei Region, Qinghai Province.展开更多
The samples collected from the surface sediments in Xiangshan Bay,Zhejiang province in May and November 2005 were analyzed under a light microscope.The species composition,abundance,community structure and diversity w...The samples collected from the surface sediments in Xiangshan Bay,Zhejiang province in May and November 2005 were analyzed under a light microscope.The species composition,abundance,community structure and diversity were investigated.A total of 179 taxa belonging to 46 genera of diatom were identified.The result showed that the ecotypes of diatom were mostly eurytopic species,followed by warm water species and temperate species.The most dominant species were Cyclotella stylorum and Coscinodiscus jonesianus.The seasonal variation of diatom abundance was remarkable.The cell abundance of diatoms was higher in spring(2.974×10^3 cells/g)than that in autumn(0.071×10^3 cells/g).The number of species varies with change of season,demonstrating the adaptability of diatoms to the temperature of water.The species diversity of benthic diatom was lower in autumn than that in spring.展开更多
Aims As a unique geographical unit of the earth,the tibetan Plateau is extensively covered by various Stipa communities.However,their vegetation features have not been reported systematically till now,especially in so...Aims As a unique geographical unit of the earth,the tibetan Plateau is extensively covered by various Stipa communities.However,their vegetation features have not been reported systematically till now,especially in some scantily explored regions.In this study,we endeavor to reveal the community types,quantitative charac-teristics and climatic distribution patterns of Stipa steppes in these areas based on primary relevés obtained from fieldwork.Methods We collected a total of 223 plots in 79 study sites in the Changthang Plateau and the Yarlung Zangbo Valley,ranging from 79°E to 91°E.the categories of Stipa formations were identified according to the classification scheme in Vegetation of China and then verified by Nonmetric Multidimensional Scaling.We performed detrended correspondence analysis and detrended canonical correspondence analysis to hunt for the alteration of Stipa communities along the precipitation gradient.Quantitative characteristics including species richness,coverage,biomass as well as importance values(IV)of dominant species were calcu-lated and visualized,respectively.Important Findings Stipa steppes in scantily explored regions of the tibetan Plateau are classified into 11 formations but major formations are rather limited in number.Formation(form.)Stipa purpurea is the most widespread Stipa assemblages not only in scantily explored regions but also across the whole tibetan Plateau.the characteristics of Stipa com-munities,including coverage,species richness,productivity and IV of dominant species,demonstrate the features of typical alpine steppes on the tibetan Plateau.Precipitation proves to be the prime climatic factor controlling the distribution patterns of Stipa assemblages.Form.Stipa subsessiliflora var.basiplumosa and form.Stipa glareosa normally distribute in arid habitats,but rainfall for the former is of greater variance.Form.Stipa roborowskyi and form.Stipa capillacea favor moderately moist environment.Form.Stipa purpurea and form.Stipa roborowskyi can tolerate a fairly broad range of precipitation.展开更多
The continuous increase of livestock production in Inner Mongolia has caused severe degradation of the grassland ecosystems in recent years. Previous grazing experiments have shown a wide range of vegetation responses...The continuous increase of livestock production in Inner Mongolia has caused severe degradation of the grassland ecosystems in recent years. Previous grazing experiments have shown a wide range of vegetation responses between the biome types on a global scale, but there is still a lack of sufficient studies to discern the relative responses of a given biome type. We conducted a meta-analysis of vegetation coverage(VC), plant density(PD), total biomass(TB), above-ground biomass(AGB), under-ground biomass(UGB) and Shannon–Weaver Index(SI) in different grassland types in Inner Mongolia obtained under conditions of different grazing intensities and durations. The results showed that grazing decreased VC, TB, AGB, UGB, and PD significantly. Compared to the global and national average values, the negative effects of grazing to steppe biomass in Inner Mongolia were higher than that on the global scale, while less pronounced than that in China. TB of the meadow steppe in Inner Mongolia increased by 40% under moderate grazing intensity and duration because of compensatory growth. SI of the desert and meadow steppe showed negative linear relationships with the grazing intensity in Inner Mongolia. The percentage changes in AGB, PD, and SI to grazing showed quadratic relationships with the mean annual temperature of the experimental year. With increasing mean annual precipitation, the negative effects of grazing on UGB and SI first decreased and then increased, with that of VC and grazing showing a cubic relationship.展开更多
In this study,a systematic survey of cultural airborne fungi was carried out in the occurrence environments of wall paintings that are preserved in the Tiantishan Grottoes and the Western Xia Museum,China.A bio-aeroso...In this study,a systematic survey of cultural airborne fungi was carried out in the occurrence environments of wall paintings that are preserved in the Tiantishan Grottoes and the Western Xia Museum,China.A bio-aerosol sampler was used for sampling in four seasons in 2016.Culture-dependent and-independent methods were taken to acquire airborne fungal concentration and purified strains;by the extraction of genomic DNA,amplification of fungal ITS rRNA gene region,sequencing,and phylogenetic analysis,thereafter the fungal community composition and distribution characteristics of different study sites were clarified.We disclosure the main environmental factors which may be responsible for dynamic changes of airborne fungi at the sampling sites.The concentration of cultural airborne fungi was in a range from 13 to 1,576 CFU/m^(3),no significant difference between the two sites at the Tiantishan Grottoes,with obvious characteristics of seasonal variation,in winter and spring were higher than in summer and autumn.Also,there was a significant difference in fungal concentration between the inside and outside of the Western Xia Museum,the outside of the museum was far more than the inside of the museum in the four seasons,particularly in the winter.Eight fungal genera were detected,including Cladosporium,Penicillium,Alternaria,and Filobasidium as the dominant groups.The airborne fungal community structures of the Tiantishan Grottoes show a distinct characteristic of seasonal variation and spatial distribution.Relative humidity,temperature and seasonal rainfall influence airborne fungal distribution.Some of the isolated strains have the potential to cause biodeterioration of ancient wall paintings.This study provides supporting information for the pre-warning conservation of cultural relics that are preserved at local sites and inside museums.展开更多
General Secretary Xi Jinping’s Report to the 19th National Congress of the CPC on the international situation and Chinese foreign affairs entitled'adhering to the peaceful development road and promoting the const...General Secretary Xi Jinping’s Report to the 19th National Congress of the CPC on the international situation and Chinese foreign affairs entitled'adhering to the peaceful development road and promoting the construction of a community with a shared future for mankind',systematically展开更多
Healthy soils are essential for sustainableagricultural development and soil health requires carefulassessment with increasing societal concern over envir-onmentally friendly agricultural development. Soil healthis th...Healthy soils are essential for sustainableagricultural development and soil health requires carefulassessment with increasing societal concern over envir-onmentally friendly agricultural development. Soil healthis the capacity of soil to function within ecologicalboundaries to sustain productivity, maintain environmentalquality, and promote plant and animal health. Physical,chemical and biological indicators are used to evaluate soilhealth;the biological indicators include microbes, proto-zoa and metazoa. Nematodes are the most abundantmetazoa and they vary in their sensitivity to pollutants andenvironmental disturbance. Soil nematode communitiesare useful biological indicators of soil health, withcommunity characteristics such as abundance, diversity,community structure and metabolic footprint all closelycorrelated with the soil environment. The community size,complexity and structure reflect the condition of the soil.Both free-living and plant parasitic nematodes are effec-tive ecological indicators, contributing to nutrient cyclingand having important roles as primary, secondary andtertiary consumers in food webs. Tillage inversion,cropping patterns and nutrient management may havestrong effects on soil nematodes, with changes in soilnematode communities reflecting soil disturbance. Somefree-living nematodes serve as biological models to testsoil condition in the laboratory and because of theseadvantages soil nematodes are increasingly being used asbiological indicators of soil health.展开更多
A 1-year baseline survey was conducted in north-western China to evaluate the ecological restoration quality of grain for green(GFG)using soil ciliate communities.The aims of this study were focused on analyzing the c...A 1-year baseline survey was conducted in north-western China to evaluate the ecological restoration quality of grain for green(GFG)using soil ciliate communities.The aims of this study were focused on analyzing the changes of soil ciliate communities in four plots(A,GFG for 15 years;B,GFG for 13 years;C,layland;D,cultivated land)for GFG environmental assessment.Simultaneously we studied the effects of vegetation communities and physical-chemical variables with GFG changes on soil ciliates.A total of 114 species of ciliates were identified among the four sample sites,representing 9 classes,14 orders,22 families and 37 genera.The community patterns of the soil ciliates were significantly correlated with the individual abundance of aboveground plants,soil water content,and soil porosity.The contents of total nitrogen were the main factor affecting the soil ciliate community composition.The species number,individual abundance,and diversity index of the ciliates were each in the order A>B>C>D;that is,the community composition of ciliates was complicated with the implementation of the GFG.It was shown that the succession of ciliate community shifts toward promoting the complexity with the progress of GFG.These findings demonstrate that soil ciliate communities may be used as a useful indicator to evaluate the effects of the ecological restoration quality of GFG.展开更多
基金Supported by Special Fund for Agro-scientific Research in the Public Interest(201003019,201003061,201303060)the National Natural Science Foundation of China(41201199)+1 种基金International Science and Technology Cooperation Project(2012DFA31290)Modern Agricultural Technology System of Special Funding~~
文摘[Objective] The aim was to explore the management mode on optimal re-sources al ocation of family ranch in meadow steppe. [Method] Three double repre-sentative family ranches were selected in meadow steppe of Hulunber Old Barag Banner, and the study was carried out with the baseline survey. Three family ranches were selected as the demonstrative households for the corporation study, while other three family ranches with the similar conditions were looked as the non-demonstrative households for the comparison. Demonstrative households of the fami-ly ranches reduced the stocking rate, optimized the flock structure and took a winter feeding and other means to explore the different management models on plant com-munity characteristic of family ranch. [Result] The seasonal dynamic of community characteristic in family ranches showed the single-peaks curves. The seasonal dy-namics of community coverage, height and biomass in the demonstrative households showed higher compared with the non-demonstrative households, and community density in the experiment households was lower than that of the control experiment households. Community coverage, height and biomass of degraded grassland in family ranch have a great improve after optimization of management. Community coverage, height , density and biomass were increasing in fencing plot, but decreas-ing in free grazing area. Enclosure improved grassland coverage, vegetation height, density and forage yield. Leymus chinensis played an important role in plant com-munity. The important values of Leymus chinensis, Stipa baicalensis, Cleistogenes squarrosa, and Carex duriuscula were high. Leymus chinensis important value in the demonstrative households of optimal management was higher than that in the non-demonstrative households, and Carex duriuscula important value of the non-demon-strative households was significantly higher than that of the demonstrative house-holds. The indexes of Margalef richnes,Shannon-Wiener diversity, Simpson diversity and Pielou uniformity showed that the demonstrative households were higher than the non-demonstrative households. [Conclusion] The research provides theoretical ref-erences for sustainable development of pastures dominated by family ranch.
基金supported by the National Hi-Tech Research and Development Program (863) of China(No. 2002AA601120)the National Key TechnologyR &D Program:Shanghai China Expo-Tech Project (No.2007BAK27B05)
文摘Biologically active carbon (BAC) system was set up in a water plant of South China during January to December 2007,to study the invertebrate community characteristics of BAC filter.Thirty-seven invertebrate species were found,of which 28 belonging to rotifers.Filter operation could lead to an output of invertebrates in high abundances with the filtrate,and the maximum density could reach 5608 individuals/m 3.Average abundances in the effluent water increased in 27-33 folds in comparison to the influent water during the sampling period.Invertebrate community succession had the following trend:filter-feeding animals → small benthic invertebrates → large benthic and resistant invertebrates.Abundances of large-sized invertebrates (copepod adult and oligochaete) at bigger-media column were significantly higher than that at small-media column.The results implied the abundant species diversity of invertebrate in BAC filter.The relationship between invertebrate and biofilm still remain to be studied in detail.
基金The work was supported by the National Natural Science Foundation of China under contract !No. 49576275.
文摘The Paper is the succession of the study on abundance distribution of planktonic copepods in the waters north of Taiwan, and the emphasis is laid on the analysis and discussion of the constructions and features of copepod community and the relationships with water environment. The results show as follows: a total of 237 species were identified and the construction of communtity was complex. The percentage of annual present species was only 32%. The mean values of diversity and homogeneity of the copepod community were 3. 714 and 0. 690 respectively, and their horizontal distribution patterns were higher in outshore area than in nearshore area. The copepods of the area could be divided into five ectotypes. Warm-water outshore high temperature and lower saline group and tropic oceanic high temperature and saline group could indicate the seasonal changes of the Taiwan Strait water and the Kuroshio surface water respectively. According to the various aspects of calculation and analysis, winter was different from other three seasons in environmental conditions. In spring, summer and autumn, Undinula valgaris was the meat dominant species and salinity was the main factor that affected the community feature values. The communities in the three seasons had the subtropic-tropic characteristics in which warm-water outshore species were dominant and tropic oceanic species accounted for also certain proportion. While in winter, the dominant species was Euchaeta manna and temperature was the main factor influencing the community feture values. The community had the tropic oceanic characteristics in which tropic oceanic species were dominant.
文摘The change of plant community character during recovery succession processes of high mountain meadow in Naqu, Tibet, was investigated. The results show that there are 41 plant species in the inventoried quadrates. The high-plants in four big families plays important roles in natural vegetation recovery, while Kobresia play an important role in climax communities. The plant species components changed with each succession stage. The plant species were mainly annual and biennial during the early succession stage, and perennial during the medium; and dominated by Kobresia humilis during the late. Potentilla bifurca and Potentilla tanaletfolia were both found in all stages. The accumulated number of family, genus, and species during the succession process varied quadric with the stages. The main plant community characteristics varied logistically with the succession stages except the height. The community characteristics mainly affected by dominant species which were changed in same rhythms. The biomass under ground was far more than the upground. The plant diversity inflated in the medium stage.
基金Sponsored by Global Change Special Funded Project of National Key Scientifi c Research Program(2013CB956000)
文摘As a typical inland wetland, Yangguan nature reserve wetland in Dunhuang is one of the important stops of migratory route for birds, which is vulnerable and particular. Study on the community characteristics and species diversity of wetland has great signifi cance for biodiversity protection. Based on the fi eld investigation, the fl oristic composition, geographical elements and species diversity of wetland plants were studied in Yangguan reserve of Dunhuang. The results showed that 26 families, 56 genera and 74 species were recorded in the study area. The largest families were the Gramineae and Chenopodiaceae, accounting for 29.73% of the total. Herbs were the most abundant life-form, accounting for 77.03% of the total. The fl oral geographical elements of the plants were mainly composed of temperate zone distribution type. By using two way indicator species analysis(TWINSPAN), the vegetation in 36 sampling plots could be classifi ed into 8 communities. The species diversity indexes of communities were relatively low, but had large differences among each other. According to the importance value, the Margalef richness index(Rm) ranged from 0 to 4.200. Simpson diversity index(D) was between 0 and 0.512; Shannon diversity index(H) ranged from 0 to 1.400, and Pielou evenness index(J) was within the range of 0.538 to 1.000. The results indicated that the plant species were relatively rare and simple in general, the species diversity of communities was low, and the ecological environment was fragile in Yangguan nature reserve of Dunhuang.
基金Supported by Fund on the National Key Technology R&D Program of the Ministry of Science and Technology of China(2012BAD18B022012BAD18B01-2)+1 种基金The National Public Welfare Industry(Agriculture)Special Program(201003068)The Special Project for the Social Common Wealth Research of the National Science Research Institute(2015TS05)
文摘In order to understand the biological community characteristics of different surface treatments of 'artificial reef templates ,which had been placed on the offshore, Yuanzhou island, Daya Bay. Sampling survey was taken in August of 2014. The results showed that 39 species of fouling organisms were collected and iden- tiffed, Ostrea nigromarginata has attached the absolute position of the dominant species ; Through the concrete block surface treatment has a better biofouling effect, and red brick, granite plates and no-surface-treated concrete template attached biomass and abundance of organisms were very low ; Biomass and abundance indices and ecological indices do not show a certain degree of regularity.
基金Supported by National Natural Science Foundation of China (31270740)Natural Science Foundation of Hubei Province (2017CFB390)。
文摘[Objectives]This study was conducted to analyze species composition, community appearance, plant life-type spectrum, flora distribution, plant community structure and plant diversity indexes of Mingyue Park in Jingzhou City, as well as the ecological functions of plants in cooling, humidification, shading, and noise reduction. [Methods] A quadart method was used to investigate plant communitues of Mingyue Park in Jingzhou City. [Results] There were 141 species in the park, including 44 tree speceies, 35 shrub speceies, and 62 herb speceies. The arber-shrub-grass structure was the dominant plant community structure. The Simpson index(D), Shannon-Wiener index(H) and Pielou index(J) of the herb layer were higher than those of the tree layer and the shrub layer, and the shrub layer was the lowest. The results of ecological function research showed that the plant communities had a significant shading effect and a certain ability to reduce noise. The comprehensive conclusion showed that the ecological function indexes of the arbor-shrub-grass structure in Mingyue Park were significantly higher than those of the arbor-shrub structure and the single-tree structure. In order to improve the ecological benefits of plant communities in Mingyue Park, the plant diversity can be increased in the later construction to enrich community structures. [Conclusions] This study evaluated the ecological benefits of plant communities in Mingyue Park, and provides a scientific basis for the plant configuration of parks in Jingzhou and other regions.
基金Supported By the Second National Investigation of Key Wild Plant Resources-Special Investigation of Picea neoveitchii Mast.Resources in Hubei Province
文摘In this paper,the geographical distribution,community characteristics and DBH class structure of Picea neoveitchii Mast. population were investigated and analyzed by systematical and ecological approaches. In addition,the endangered mechanism and the protection measures were put forward by analyzing the Picea neoveitchii Mast. resource distribution in Hubei Province to provide effective scientific basis for further research. The results showed that Picea neoveitchii Mast. was found in Baokang,Enshi,Shennongjia and Zhuxi of Hubei Province,there were 9 distribution points and only a wild forest was found in Baokang. The community of Baokang County was not rich in species composition and 32 species,29 genera and 21 families were examined. Meanwhile,temperate zone was the main flora element of this community,the phaenerophytes plant was most dominant and there were few hemicryptophytes and it lacked therophytes. In this community,Picea neoveitchii Mast. was in a dominant position,including lots of treelets,so the age structure of the population was growing.
基金National Key Research and Development Program of China(2022YFD1300803)National Natural Science Foundation of China(42377357).
文摘Soil erosion caused by unsustainable grazing is a major driver of grassland ecosystem degradation in many semi-arid hilly areas in China.Thus,grazing exclusion is considered as an effective method for solving this issue in such areas.However,some ecological and economic problems,such as slow grassland rejuvenation and limited economic conditions,have become obstacles for the sustainable utilization of grassland ecosystem.Accordingly,we hypothesized that the conflict between grassland use and soil conservation may be balanced by a reasonable grazing intensity.In this study,a two-year grazing fence experiment with five grazing intensity gradients was conducted in a typical grassland of the Loess Plateau in China to evaluate the responses of vegetation characteristics and soil and water losses to grazing intensity.The five grazing intensity gradients were 2.2,3.0,4.2,6.7,and 16.7 goats/hm2,which were represented by G1-G5,respectively,and no grazing was used as control.The results showed that a reasonable grazing intensity was conducive to the sustainable utilization of grassland resources.Vegetation biomass under G1-G4 grazing intensity significantly increased by 51.9%,42.1%,36.9%,and 36.7%,respectively,compared with control.In addition,vegetation coverage increased by 19.6%under G1 grazing intensity.Species diversity showed a single peak trend with increasing grazing intensity.The Shannon-Wiener diversity index under G1-G4 grazing intensities significantly increased by 22.8%,22.5%,13.3%,and 8.3%,respectively,compared with control.Furthermore,grazing increased the risk of soil erosion.Compared with control,runoff yields under G1-G5 grazing intensities increased by 1.4,2.6,2.8,4.3,and 3.9 times,respectively,and sediment yields under G1-G5 grazing intensities were 3.0,13.0,20.8,34.3,and 37.7 times greater,respectively,than those under control.This result was mainly attributed to a visible decrease in litter biomass after grazing,which decreased by 50.5%,72.6%,79.0%,80.0%,and 76.9%,respectively,under G1-G5 grazing intensities.By weighing the grassland productivity and soil conservation function,we found that both two aims were achieved at a low grazing intensity of less than 3.5 goats/hm2.Therefore,it is recommended that grassland should be moderately utilized with grazing intensity below 3.5 goats/hm2 in semi-arid hilly areas to achieve the dual goals of ecological and economic benefits.The results provide a scientific basis for grassland utilization and health management in semi-arid hilly areas from the perspective of determining reasonable grazing intensity to maintain both grassland production and soil conservation functions.
基金the Open Fund of Sandong Provincial Key Laboratory of Marine Ecology and Environment & Disaster Prevention and Mitigation(Grant No.2011007)the Major Programs of Marine Public Welfare(Grant No.201105005)
文摘The macrobenthic community of the Xiaoqing River Estuary and the adjacent sea waters was investigated in May and November 2008,August 2009,and May and September 2010,respectively.A total of 95 species of macrobenthos were identified in the five cruises and most of them were polychaetes(46.39%),mollusks(28.86%) and crustaceans(20.62%).The Shannon-Wiener index of macrobenthos was lower than 2 in 67% sites.Along the stream channel,estuary and the coastal waters,the species of polychaetes reduced gradually,while the abundance increased at first and then decreased.The abundance was the biggest at regions with salinity of 5 20 in the estuary.The species and abundance of mollusks and crustaceans increased gradually.As for seasonal distribution,the species,abundance and biomass were higher in spring and lower in summer and autumn.Contemporaneously compared with Laizhou Bay and Yellow River Estuary,the species of macrobenthos appeared in the Xiaoqing River Estuary were much less,while the percentage of polychaetes was higher.Abundance and biomass were higher in Xiaoqing River estuary,then consequently followed by Laizhou Bay and Yellow River Estuary.The dominant species in Xiaoqing River Estuary was polychaete,and Layzhou Bay mollusk.The community structure characteristics of macrobenthos in the Xiaoqing River Estuary revealed a significant pollution status in this region.
基金funded by the National Basic Research Program of China (2009CB421303)the Key Project in Science & Technology Program of Xinjiang Uygur Autonomous Region (200933125)the Science and Technology Ministry Program (2009BAC54B03)
文摘The paper analyzes the hypothesis that the distribution of dominant plant species and characteristics of plant communities are related to groundwater depth. The results showed that variations of groundwater depth impacted distributions and characteristics of dominant plant communities. However, besides groundwater depth, the community composition and species diversity were also influenced by physiognomy of the habitat. Based on the similarity coefficient, the differences between dominant plant communities were significant at different groundwater depths. Compared with other results relating to desert vegetation and groundwater depth, variations of community distribution were similar at the large spatial scale. However, in this extremely arid region, there were significant differences in community type and community succession when compared with other arid regions, especially in relationship to deep groundwater depth. With groundwater depth from deep to shallow, communities transformed with the sequence of Alhagi communities, Tamarix spp. communities, Populus communities, Phragmites communities, and Sophora communities. At groundwater depth of less than 6.0 m, the community type and composition changed, and the species diversity increased. Among these dominant species, Tamarix exhibited the biggest efficiency in resource utilization according to niche breadth, which means it possessed the best adaptability to environmental conditions at the oasis margins.
基金Supported by Technology R&D Program"Research and Demonstration of Fragile Ecological Restoration Technology for the Tibetan Plateau"(2013BAC04B02)Sub Project of National Key Technology R&D Program"Health Assessment Technology for Typical Fragile Ecosystem in the Tibetan Plateau"(2013BAC04B02-05)National Natural Science Foundation of China(31160120)
文摘[ Objective ] The paper was to understand the characteristics of plant communities in three kinds of typical alpine meadows in Haibei Region, Qinghai Province. [ Method] The characteristics and diversity of plant communities in typical alpine meadow, including Kobresia humilis, PotentiUafruticose and Kobresia menyuanica, were studied, with Menyuan studfarm in Haibei region of Qinghai Province as an example. [ Result] Results showed that the three kinds of plant communities in alpine meadows presented complex structure; the diversity index had close relationship with the evenness index; there were fewer common species and higher species replacement rate among different alpine meadow communities ; the aboveground biomass of K. humilis alpine meadow was 1.62 and 1.69 times of P. fruticose and K. menyuanica meadows, respectively; the underground biomass mainly distributed in the 0 - 10 cm soil layer, and the vertical spatial distribution structure was "T" type; the aboveground and underground biomass were negatively correlated. [ Conclusion] The paper will provide basis for protection and further use of different grassland plant communities in Haibei Region, Qinghai Province.
基金funded by the National Key Research and Development Program of China(Grant No.2016YFA0601302)the Natural Science Foundation of China(Grant No.41876146,No.41476116)the China-EU Cooperation Project:Ecological farming research in coastal zone composite system(INCO-CT-2004-510706).
文摘The samples collected from the surface sediments in Xiangshan Bay,Zhejiang province in May and November 2005 were analyzed under a light microscope.The species composition,abundance,community structure and diversity were investigated.A total of 179 taxa belonging to 46 genera of diatom were identified.The result showed that the ecotypes of diatom were mostly eurytopic species,followed by warm water species and temperate species.The most dominant species were Cyclotella stylorum and Coscinodiscus jonesianus.The seasonal variation of diatom abundance was remarkable.The cell abundance of diatoms was higher in spring(2.974×10^3 cells/g)than that in autumn(0.071×10^3 cells/g).The number of species varies with change of season,demonstrating the adaptability of diatoms to the temperature of water.The species diversity of benthic diatom was lower in autumn than that in spring.
基金Key Program of National Fundamental Scientific Research funded by the Ministry of Science and Technology of China:Integrated Scientific Investigation in Data-deficient Regions of the Tibetan Plateau(2012FY111400)Redaction of Vegetation of China(2015FY210200).
文摘Aims As a unique geographical unit of the earth,the tibetan Plateau is extensively covered by various Stipa communities.However,their vegetation features have not been reported systematically till now,especially in some scantily explored regions.In this study,we endeavor to reveal the community types,quantitative charac-teristics and climatic distribution patterns of Stipa steppes in these areas based on primary relevés obtained from fieldwork.Methods We collected a total of 223 plots in 79 study sites in the Changthang Plateau and the Yarlung Zangbo Valley,ranging from 79°E to 91°E.the categories of Stipa formations were identified according to the classification scheme in Vegetation of China and then verified by Nonmetric Multidimensional Scaling.We performed detrended correspondence analysis and detrended canonical correspondence analysis to hunt for the alteration of Stipa communities along the precipitation gradient.Quantitative characteristics including species richness,coverage,biomass as well as importance values(IV)of dominant species were calcu-lated and visualized,respectively.Important Findings Stipa steppes in scantily explored regions of the tibetan Plateau are classified into 11 formations but major formations are rather limited in number.Formation(form.)Stipa purpurea is the most widespread Stipa assemblages not only in scantily explored regions but also across the whole tibetan Plateau.the characteristics of Stipa com-munities,including coverage,species richness,productivity and IV of dominant species,demonstrate the features of typical alpine steppes on the tibetan Plateau.Precipitation proves to be the prime climatic factor controlling the distribution patterns of Stipa assemblages.Form.Stipa subsessiliflora var.basiplumosa and form.Stipa glareosa normally distribute in arid habitats,but rainfall for the former is of greater variance.Form.Stipa roborowskyi and form.Stipa capillacea favor moderately moist environment.Form.Stipa purpurea and form.Stipa roborowskyi can tolerate a fairly broad range of precipitation.
基金The National Key Research and Development Program of China (2017YFA0604803)。
文摘The continuous increase of livestock production in Inner Mongolia has caused severe degradation of the grassland ecosystems in recent years. Previous grazing experiments have shown a wide range of vegetation responses between the biome types on a global scale, but there is still a lack of sufficient studies to discern the relative responses of a given biome type. We conducted a meta-analysis of vegetation coverage(VC), plant density(PD), total biomass(TB), above-ground biomass(AGB), under-ground biomass(UGB) and Shannon–Weaver Index(SI) in different grassland types in Inner Mongolia obtained under conditions of different grazing intensities and durations. The results showed that grazing decreased VC, TB, AGB, UGB, and PD significantly. Compared to the global and national average values, the negative effects of grazing to steppe biomass in Inner Mongolia were higher than that on the global scale, while less pronounced than that in China. TB of the meadow steppe in Inner Mongolia increased by 40% under moderate grazing intensity and duration because of compensatory growth. SI of the desert and meadow steppe showed negative linear relationships with the grazing intensity in Inner Mongolia. The percentage changes in AGB, PD, and SI to grazing showed quadratic relationships with the mean annual temperature of the experimental year. With increasing mean annual precipitation, the negative effects of grazing on UGB and SI first decreased and then increased, with that of VC and grazing showing a cubic relationship.
基金This study was supported by the National Natural Science Foundation of China(Nos.32060258,32060277)Science and Technology Plan of Gansu Province(Nos.20YF8WF016+1 种基金18JR3RA004)the"Light of West China"Program of the Chinese Academy of Sciences and Project of Gansu Cultural Relics Bureau(GWJ202011).
文摘In this study,a systematic survey of cultural airborne fungi was carried out in the occurrence environments of wall paintings that are preserved in the Tiantishan Grottoes and the Western Xia Museum,China.A bio-aerosol sampler was used for sampling in four seasons in 2016.Culture-dependent and-independent methods were taken to acquire airborne fungal concentration and purified strains;by the extraction of genomic DNA,amplification of fungal ITS rRNA gene region,sequencing,and phylogenetic analysis,thereafter the fungal community composition and distribution characteristics of different study sites were clarified.We disclosure the main environmental factors which may be responsible for dynamic changes of airborne fungi at the sampling sites.The concentration of cultural airborne fungi was in a range from 13 to 1,576 CFU/m^(3),no significant difference between the two sites at the Tiantishan Grottoes,with obvious characteristics of seasonal variation,in winter and spring were higher than in summer and autumn.Also,there was a significant difference in fungal concentration between the inside and outside of the Western Xia Museum,the outside of the museum was far more than the inside of the museum in the four seasons,particularly in the winter.Eight fungal genera were detected,including Cladosporium,Penicillium,Alternaria,and Filobasidium as the dominant groups.The airborne fungal community structures of the Tiantishan Grottoes show a distinct characteristic of seasonal variation and spatial distribution.Relative humidity,temperature and seasonal rainfall influence airborne fungal distribution.Some of the isolated strains have the potential to cause biodeterioration of ancient wall paintings.This study provides supporting information for the pre-warning conservation of cultural relics that are preserved at local sites and inside museums.
文摘General Secretary Xi Jinping’s Report to the 19th National Congress of the CPC on the international situation and Chinese foreign affairs entitled'adhering to the peaceful development road and promoting the construction of a community with a shared future for mankind',systematically
基金the National KeyResearch and Development Program of China (2017YFD0202102,2016YFD0200405, and 2016YFE0101100).
文摘Healthy soils are essential for sustainableagricultural development and soil health requires carefulassessment with increasing societal concern over envir-onmentally friendly agricultural development. Soil healthis the capacity of soil to function within ecologicalboundaries to sustain productivity, maintain environmentalquality, and promote plant and animal health. Physical,chemical and biological indicators are used to evaluate soilhealth;the biological indicators include microbes, proto-zoa and metazoa. Nematodes are the most abundantmetazoa and they vary in their sensitivity to pollutants andenvironmental disturbance. Soil nematode communitiesare useful biological indicators of soil health, withcommunity characteristics such as abundance, diversity,community structure and metabolic footprint all closelycorrelated with the soil environment. The community size,complexity and structure reflect the condition of the soil.Both free-living and plant parasitic nematodes are effec-tive ecological indicators, contributing to nutrient cyclingand having important roles as primary, secondary andtertiary consumers in food webs. Tillage inversion,cropping patterns and nutrient management may havestrong effects on soil nematodes, with changes in soilnematode communities reflecting soil disturbance. Somefree-living nematodes serve as biological models to testsoil condition in the laboratory and because of theseadvantages soil nematodes are increasingly being used asbiological indicators of soil health.
基金the National Natural Science Foundation of China(Project number:41761056,41361055,42067012).
文摘A 1-year baseline survey was conducted in north-western China to evaluate the ecological restoration quality of grain for green(GFG)using soil ciliate communities.The aims of this study were focused on analyzing the changes of soil ciliate communities in four plots(A,GFG for 15 years;B,GFG for 13 years;C,layland;D,cultivated land)for GFG environmental assessment.Simultaneously we studied the effects of vegetation communities and physical-chemical variables with GFG changes on soil ciliates.A total of 114 species of ciliates were identified among the four sample sites,representing 9 classes,14 orders,22 families and 37 genera.The community patterns of the soil ciliates were significantly correlated with the individual abundance of aboveground plants,soil water content,and soil porosity.The contents of total nitrogen were the main factor affecting the soil ciliate community composition.The species number,individual abundance,and diversity index of the ciliates were each in the order A>B>C>D;that is,the community composition of ciliates was complicated with the implementation of the GFG.It was shown that the succession of ciliate community shifts toward promoting the complexity with the progress of GFG.These findings demonstrate that soil ciliate communities may be used as a useful indicator to evaluate the effects of the ecological restoration quality of GFG.