Relationships between topography,soil properties and the distribution of plant communities on two different rocky hillsides are examined in two subtropical karst forests in the Maolan National Natural Reserve,southwes...Relationships between topography,soil properties and the distribution of plant communities on two different rocky hillsides are examined in two subtropical karst forests in the Maolan National Natural Reserve,southwestern China.Surveys of two 1-ha permanent plots at each forest,and measurements of four topographic and thirteen edaphic factors on the slopes were performed.Twoway Indicator Species Analysis(TWINSPAN) and Detrended Canonical Correspondence Analysis(DCCA) were used for the classification of plant communities and for vegetation ordination with environmental variables.One hundred 10m×10m quadrats in each plot were classified into four plant community types.A clear altitudinal gradient suggested that elevation was important in community differentiation.The topography and soil explained 51.06% and 54.69% of the variability of the distribution of plant species in the two forest plots,respectively,indicating both topographic factors(eg.elevation,slope and rock-bareness rate) and edaphic factors(e.g.total P,K and exchangeable Ca) were the important drivers of the distribution of woody plant species in subtropical karst forest.However,our results suggested that topographical factors were more important than edaphic ones in affecting local plant distribution on steep slopes with extensive rock outcrops,while edaphic factors were more influential on gentle slope and relatively thick soil over rock in subtropical karst forest.Understanding relationships between vegetation and environmental factors in karst forest ecosystems would enable us to apply these findings in vegetation management strategies and restoration of forest communities.展开更多
Our work aimed to test the hypothesis that soil microscale heterogeneity act as a community ecological driver,increasing diversity and promoting structural shifts on the Seasonally Dry Tropical Forest(SDTF)tree commun...Our work aimed to test the hypothesis that soil microscale heterogeneity act as a community ecological driver,increasing diversity and promoting structural shifts on the Seasonally Dry Tropical Forest(SDTF)tree community.We evaluated the relationship between microscale edaphic variations and floristic–structural patterns of tree communities in a SDTF fragment located in the southern end of the Brazilian Caatinga domain.Vegetation and soil data were obtained through 27 sample units of 400 m2(20 m 920 m),within each one we measured and identified at species level all arboreal individuals with Circumference at the Breast Height greater or equal to 10 cm,and also collected the soil samples.Through the data we evaluated soil variation influence on the tree community structural and floristic patterns trough generalized linear models.Soil explained the small-scale structural and floristic variations,contributing significantly to biomass,sprouting and to floristic relationships between sample units.It was also observed a possible relation of the result with the Caatinga domain biogeographic history,due the presence of Sedimentary Caatinga species,which are not expected for the study region.Soil plays an important role in driving small-scale complexity and diversity of SDTF,but we also suggest that Caatinga biogeographic events have influence on the high heterogeneity patterns.展开更多
The regulatory functions of soil are getting attention among the scientists and Soil Organic Carbon (SOC) is an important indicator of soil health. The impact of differential use of land on SOC and other edaphic prope...The regulatory functions of soil are getting attention among the scientists and Soil Organic Carbon (SOC) is an important indicator of soil health. The impact of differential use of land on SOC and other edaphic properties were analysed in three important Land use land cover (LULC) system of Tripura, northeast India. Soil cores were divided into four depth profiles (0 - 10, 10 - 30, 30 - 50 and 50 - 100 cm) to observe the changes of edaphic properties into the soil depth gradient. Our results suggest that SOC in the top profile of Managed Plantation (MP) and Jhum Fellow (JF) was 51.68% and 48.55%, less than Natural Forest (NF). From 0 - 10 to 10 - 30 cm soil depth, 43.3%, 8.4% and 39.4% decrease in NF MP and JF found. Total stock of SOC (Mg C·ha<sup>﹣</sup><sup>1</sup>) was found highest in JF (121.87), followed by NF (117.12) and MP (85.34). In top profile, conversion of NF into MP and NF into JF led to 39% and 11% decrease in SOC. The significant variation in SOC stock was found among different LULC under this study (F<sub>2,12</sub> = 16.94, P ≤ 0.001). In 0 - 10 cm soil depth, maximum value of bulk density (gm·cm<sup>﹣</sup><sup>3</sup>) was found in MP (1.39) followed by JF (1.27) and NF (1.23). In top profile, significant variation was found among LULC (p < 0.001). Soil pH and moisture content significantly varied (p < 0.05) in 0 - 10, 10 - 30 and 50 - 100 cm soil depth. In contrast to that significant change in soil temperature was found at 30 - 50 cm (p < 0.001) and 50 - 100 cm (p < 0.001). It was observed that JF had highest overall SOC stock than NF and MP. Conversion of NF into MP and JF results significant loss of SOC at 0 - 10 and 10 - 30 cm depth profile. We also found that NF conversion had significant impact on the change in the soil C pool.展开更多
Osyris lanceolata is heavily and illegally exploited in East Africa for its essential oils, yet little is known about its population status and ecological requirements. This study examined its population structure and...Osyris lanceolata is heavily and illegally exploited in East Africa for its essential oils, yet little is known about its population status and ecological requirements. This study examined its population structure and environmental factors influencing its distribution in the semi-arid Karamoja sub-region, Uganda. We surveyed 388 plots (5 m radius) at different altitudes, recording life stages, stem diameters, and regeneration patterns, and analyzed soil samples. Multivariate analyses, including Canonical Correspondence Analysis (CCA), Detrended Correspondence Analysis (DCA), Non-metric Multidimensional Scaling (NMDS), and Multiple Regression Modeling (MRM), identified key environmental factors affecting its distribution. Findings show that O. lanceolata populations in Moroto, Nakapiripirit, and Amudat districts are severely degraded due to overexploitation. The species is primarily regenerating through coppicing rather than seedlings, with an exploitation intensity of 56.6%. Population densities are low, distribution is irregular, and sustainable harvesting is not viable. Soil properties, particularly Ca2+, N, P, K+, Na+, and organic matter, significantly influence its abundance. Conservation efforts should focus on identifying suitable provenances for genetic preservation and plantation establishment. Areas with at least 9 trees per hectare in Moroto, Nakapiripirit, and Amudat could serve as potential sites for ex-situ plantations. Further research should explore how biotic interactions, genetic diversity, and morphology affect oil yield and quality to support restoration, breeding, and domestication initiatives.展开更多
Climate warming has intensified the global hydrological cycle,amplifying the differences in precipitation and soil moisture between arid and humid areas.Such a change under regional drought may alter nitrogen(N)and ph...Climate warming has intensified the global hydrological cycle,amplifying the differences in precipitation and soil moisture between arid and humid areas.Such a change under regional drought may alter nitrogen(N)and phosphorus(P)releases during litter decomposition in terrestrial ecosystems,but how these biogeochemical processes respond to drought differently between arid and humid areas remains unclear.Here,we compiled 259 and 138 paired observations(with and without drought conditions)to assess the global variations in the drought effects on N and P releases during litter decomposition between arid(aridity index<0.5)and humid(aridity index>0.5)areas.Litter N release increased under drought in both arid(0.35%)and humid(3.62%)areas,and P release decreased by 7.32%in arid areas but increased by 2.22%in humid areas under drought.These changes in N and P releases from decomposing litter were positively correlated with drought duration in arid areas,dependent on microclimate,edaphic factors,and litter quality.Our findings highlight the contrasting effects of drought on litter N and P releases between arid and humid ecosystems,and this differential influence will greatly improve our capability to evaluate and forecast nutrient cycling during litter decomposition under different precipitation patterns.展开更多
Aims the Cape Peninsula is a small area(471 km2)situated on the south-westernmost tip of the Core Cape Subregion(CCR)of South Africa.Within the Cape Peninsula,Fabaceae are the third most species-rich plant family(162 ...Aims the Cape Peninsula is a small area(471 km2)situated on the south-westernmost tip of the Core Cape Subregion(CCR)of South Africa.Within the Cape Peninsula,Fabaceae are the third most species-rich plant family(162 species)and they have the second highest number of endemic species after the Ericaceae.However,legumes are not the dominant taxa in the vegetation.they tend to show patchy distributions within the landscape and different species assemblages usually occupy particular niches at any given locality.the present study undertook to establish if edaphic factors influence legume species distribution in the Cape Peninsula and to determine the key indicator species for the different assemblages.Methods Soils from 27 legume sites,spanning all major geological substrates of the Cape Peninsula,were analysed for 31 chemical and physi-cal properties.Legume species present at each site were recorded and a presence/absence matrix was generated.Cluster analysis and discriminant function analysis(DFA)were run to group the sites based on overall similarity in edaphic characteristics and to identify the soil parameters contributing towards discriminating the groups.Canonical correspondence analysis(CCA)was used to test for a cor-relation between legume species compositions and edaphic factors.the strength of the association between legume species and site groupings based on edaphic properties was assessed using indicator species analysis.Important findings Based on similarity in overall soil characteristics,the sites formed three clusters:one comprising sites of sandstone geology,one with dune sand sites and the third cluster comprising sites of both shale and granite geologies(hereafter referred to as soil types).the DFA confirmed the distinctness of these clusters and the CCA showed a significant correlation between legume species composition and edaphic factors.the key edaphic parameters were clay content,iron(Fe),potassium(K),sulphur(S)and zinc(Zn).these findings reveal that the Cape Peninsula is edaphically heterogeneous and edaphically distinct habitats contain discrete legume species assemblages that can be distinguished by unique indicator species.Furthermore,multiple soil parameters,rather than a single parameter,are involved.therefore,edaphic factors play a significant role in driving the distribution of legume species in the Cape Peninsula and discrete legume species assemblages occupy distinct habitats.展开更多
Many studies have shown that climatic and edaphic factors influence the variations in nitrogen isotopes(δ^(15)N)in terrestrial ecosystems.However,the relative importance of co-varying climatic and edaphic controls on...Many studies have shown that climatic and edaphic factors influence the variations in nitrogen isotopes(δ^(15)N)in terrestrial ecosystems.However,the relative importance of co-varying climatic and edaphic controls on plantδ^(15)N remains somewhat unclear.To address this issue,regional-scale plant(L.chinensis)and soil samples were collected along a longitudinal transect across the temperate grasslands in northern China.The influences of climatic and edaphic factors on the plantδ^(15)N were disentangled using the variable importance in projection(VIP)approach.We found that the climatic and edaphic variables explained 52.4%and 31.2%,respectively,of the variation in plantδ^(15)N.The mean annual precipitation(MAP),soil N,and mean annual temperature(MAT)were the most important variables,but the soil water content(SWC),aridity index(AI),and soil clay content were also important variables.The soil pH and soil C:N ratios were identified as unimportant variables.Furthermore,a high-performance model for simulating plantδ^(15)N values was constructed based on the important variables(VIP>0.8).Further investigations should focus on the effects of the interaction between the climatic and edaphic variables on the N cycles in the temperate grasslands to provide more reliable predictions of plantδ^(15)N.展开更多
The soil properties in arid ecosystems are important determinants of vegetation distribution patterns. Soil organic carbon （SOC） content, which is closely related to soil types and the holding capacities of soil wat...The soil properties in arid ecosystems are important determinants of vegetation distribution patterns. Soil organic carbon （SOC） content, which is closely related to soil types and the holding capacities of soil water and nutrients, exhibits complex variability in arid desert grasslands; thus, it is essentially an impact factor for the distri- bution pattern of desert grasslands. In the present study, an investigation was conducted to estimate the spatial pattern of SOC content in desert grasslands and the association with environmental factors in the diluvial-alluvial plains of northern Qilian Mountains. The results showed that the mean values of SOC ranged from 2.76 to 5.80 g/kg in the soil profiles, and decreased with soil depths. The coefficients of variation （CV） of the SOC were high （ranging from 48.83% to 94.67%）, which indicated a strong spatial variability. SOC in the desert grasslands of the study re- gion presented a regular spatial distribution, which increased gradually from the northwest to the southeast. The SOC distribution had a pattern linked to elevation, which may be related to the gradient of climate conditions. Soil type and plant community significantly affected the SOC. The SOC had a significant positive relationship with soil moisture （P〈0.05）; whereas, it had a more significant negative relationship with the soil bulk density （BD） （P〈0.01）. However, a number of the variations in the SOC could be explained not by the environmental factors involved in this analysis, but rather other factors （such as grazing activity and landscape）. The results provide important references for soil carbon storage estimation in this study region. In addition, the SOC association with environmental variables also provides a basis for a sustainable use of the limited grassland resources in the diluvial-alluvial plains of north- ern Qilian Mountains.展开更多
Seven sampling sites in each of three biomes (Western Ghats, foothills of Western Ghats and west coast) of south- western India were investigated to study the distribution, abundance and ecology of pill millipedes (Ar...Seven sampling sites in each of three biomes (Western Ghats, foothills of Western Ghats and west coast) of south- western India were investigated to study the distribution, abundance and ecology of pill millipedes (Arthrosphaera) and associated fauna in relation to edaphic features. Abundance and biomass of Arthrosphaera and other millipedes were the highest in Western Ghats, while earthworms were in foothills. Arthrosphaera magna and Arthrosphaera spp. were common in Western Ghats and foothills respectively, while no Arthrosphaera were found in the west coast. None of the sampling sites consisted of more than one species of Arthrosphaera. Biomass of Arthrosphaera, other millipedes and earthworms significantly differed in Western Ghats (P = 9.48 × 10-7) and foothills (P = 1.35 × 10-8), as did the biomass of species of Arthrosphaera (P = 2.76 × 10-7) between Western Ghats and foothills. Correlation analysis revealed that biomass of Arthrosphaera was significantly (P = 0.01, r = 0.45) correlated with soil organic carbon rather than other edaphic fea- tures (pH, phosphate, calcium and magnesium). Distribution pattern, abundance, biomass and ecology of Arthrosphaera of Western Ghats in relation to soil qualities were compared with millipedes of other regions of the world.展开更多
Modern breeding primarily targets crop yield traits and is likely to influence root-associated microbiomes, which play significant roles in plant growth and health. The relative importance of soil and cultivar factors...Modern breeding primarily targets crop yield traits and is likely to influence root-associated microbiomes, which play significant roles in plant growth and health. The relative importance of soil and cultivar factors in shaping root-associated microbiomes of modern maize (Zea mays L.) remains uncertain. We conducted a pot experiment in a controlled environment using three soils (Mollisol, Inceptisol, and Ultisol) and four contrasting cultivars, Denghai 605, Nonghua 816, Qiaoyu 8, and Zhengdan 958, which are widely planted in China. We used 16S rRNA gene amplicon sequencing to characterize the bacterial communities in the bulk soil, rhizosphere, and endosphere. Our results showed that the four cultivars had different shoot biomass and root exudate total organic carbon and organic acid contents. The microbiomes in the bulk soil, rhizosphere, and endosphere were different. We observed apparent community divergence between soils rather than cultivars, within which edaphic factors substantially contributed to microbiome variation. Moreover, permutational multivariate analysis of variance corroborated significant contributions of soil type but not cultivar on the root-associated microbiome structure. Differential abundance analysis confirmed that each soil presented a distinct root microbiome, while network analysis indicated different co-occurrence patterns of the root microbiome among the three soils. The core root microbiome members are implicated in plant growth promotion and nutrient acquisition in the roots. In conclusion, root-associated microbiomes of modern maize are much more controlled by soil characteristics than by cultivar root exudation. Our study is anticipated to help improve breeding strategies through integrative interactions of soils, cultivars, and their associated microbiomes.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
The slope aspect is one of the most critical topographic factors in mountainous areas.Little is known,however,about the eff ect of the aspect on the ectomycorrhizal(ECM)fungal community.Additionally,we know very littl...The slope aspect is one of the most critical topographic factors in mountainous areas.Little is known,however,about the eff ect of the aspect on the ectomycorrhizal(ECM)fungal community.Additionally,we know very little about the composition of ECM fungal communities associated with Quercus variabilis,which is widely distributed in East Asia.In this study,we compared the richness,community composition,and exploration types of ECM fungi associated with Q.variabilis between predominantly south-and north-facing slopes in the Taihang Mountain,North China for the fi rst time.DNA was extracted from the root tips of Q.variabilis,and Illumina MiSeq sequencing was used to identify ECM fungi.In total,168 operational taxonomic units belonging to 28 genera were detected,and the ECM community was found to be dominated by Russula,Inocybe,Tomentella,Scleroderma,and Cortinarius.Compared with the north-facing slopes,the ECM communities on the south-facing slopes had higher diversity.The community composition and exploration types were directly aff ected by the slope aspect.Also,the aspect-induced edaphic variables,such as total phosphorus,total nitrogen,total potassium,pH,and soil water content,were important sources of variation in ECM fungal richness and distributions of exploration types.Diff erent genera tended to be distributed in various slope aspects.Cenococcum,Genea,and Clavulina were signifi cantly enriched in north-facing slopes,while Geopora,Helvelosebacina,Scleroderma,Gyroporus,Astraeus,Boletus,Tricholoma,Hebeloma,Cortinarius and unclassifi ed Thelephoraceae were more abundant in south-facing slopes.Hydrophobic ECM fungi were obviously enriched in the south-facing slope,but there was no statistical diff erence between hydrophilic among the south-and north-facing slopes.Our study deepened our knowledge of the aspect-driven variation in ECM fungal communities associated with Q.variabilis.展开更多
Biotic and abiotic factors control aboveground biomass(AGB)and the structure of forest ecosystems.This study analyses the variation of AGB and stand structure of evergreen broadleaved forests among six ecoregions of V...Biotic and abiotic factors control aboveground biomass(AGB)and the structure of forest ecosystems.This study analyses the variation of AGB and stand structure of evergreen broadleaved forests among six ecoregions of Vietnam.A data set of 1731-ha plots from 52 locations in undisturbed old-growth forests was developed.The results indicate that basal area and AGB are closely correlated with annual precipitation,but not with annual temperature,evaporation or hours of sunshine.Basal area and AGB are positively correlated with trees>30 cm DBH.Most areas surveyed(52.6%)in these old-growth forests had AGB of 100–200 Mg ha^-1;5.2%had AGB of 400–500 Mg ha^-1,and 0.6%had AGB of>800 Mg ha^-1.Seventy percent of the areas surveyed had stand densities of 300–600 ind.ha^-1,and 64%had basal areas of 20–40 m^2 ha^-1.Precipitation is an important factor influencing the AGB of old-growth,evergreen broadleaved forests in Vietnam.Disturbances causing the loss of large-diameter trees(e.g.,>100 cm DBH)affects AGB but may not seriously affect stand density.展开更多
Graveyards or sacred groves are often places of natural vegetation protected by spiritual believers because of their sacred beliefs and indigenous culture.A study of graveyards was conducted to determine their role in...Graveyards or sacred groves are often places of natural vegetation protected by spiritual believers because of their sacred beliefs and indigenous culture.A study of graveyards was conducted to determine their role in species conservation,community formation,and associated indicators and species composition using multivariate statistical approaches.It was hypothesized that variations in the age of graveyards would give rise to diverse plant communities under the impact of various edaphic and climatic factors.Quantitative ecological techniques were applied to determine various phytosociological attributes.All the data were put in MS Excel for analysis in PCORD and CANOCO softwares for cluster analysis(CA),two-way cluster analysis(TWCA),indicator species analysis and canonical correspondence analysis.CA and TWCA through Sorenson distance measurements identified five major graveyard plant communities:(1)FicusBougainvillea-Chenopodium;(2)Acacia-Datura-Convolvulus;(3)Ziziphus-Vitex-Abutilon;(4)Acacia-Lantana-Salsola;and(5)Melia-Rhazya-Peganum.Species such as Capparis decidua,Herniaria hirsuta,Salvadora oliedes and Populus euphratica were only present inside graveyards rather than outside and advocate the role of graveyards in species conservation.The impact of different environmental and climatic variables plus the age of the graveyards were also assessed for comparison of plant communities and their respective indicator species.The results indicate that higher chlorine concentration,age of graveyards,low soil electrical conductivity,lower anthropogenic activities,higher nitrogen,calcium and magnesium concentrations in the soil,and sandy soils were the strong environmental variables playing a significant role in the formation of graveyard plant communities,their associated indicators and species distribution patterns.These results could further be utilized to evaluate the role of edaphic and climatic factors,indicator species and conservation management practices at a greater scale.展开更多
Arbuscular mycorrhizal fungi(AMF)form a near-ubiquitous mutualistic association with roots to help plants withstand harsh environments,and play a key role in the establishment of coastal beach plant communities.Yet li...Arbuscular mycorrhizal fungi(AMF)form a near-ubiquitous mutualistic association with roots to help plants withstand harsh environments,and play a key role in the establishment of coastal beach plant communities.Yet little is known about the structure and composition of AMF communities on coastal beaches of eastern China.In this study,we investigated the occurrence,community composition and diversity of AMF associated with common wild plants on a coastal beach of North Jiangsu,China.Almost all of the local wild species were colonized by AMF except for Chenopodium album L.Thirty-seven AMF species were isolated from the rhizosphere belonging to 12 genera in seven families.Glomus was the dominant genus and Funneliformis mosseae the dominant species.The colonization,spore composition and diversity of AMF were strongly related to edaphic factors.Sodium(Na^(+))ions in the soil significantly and negatively affected the colonization rate by AMF and both soil Na^(+)levels and pH had a significant negative effect on AMF spore density and evenness.However,there was a significant positive correlation between species richness and total organic carbon.The results provide insights into soil factors affecting native AMF communities in coastal beach habitats which could benefit vegetation recovery and soil reclamation efforts.展开更多
Background:Andean montane forests(AMF)are biodiversity hotspots that provide fundamental hydrological services as well as carbon storage and sequestration.In recent decades,southern Ecuador AMFs have been seriously th...Background:Andean montane forests(AMF)are biodiversity hotspots that provide fundamental hydrological services as well as carbon storage and sequestration.In recent decades,southern Ecuador AMFs have been seriously threatened by increased logging and conversion to forest plantations with exotic species.In this context,our main objective was to evaluate the effects of AMF conversion to forest plantations on soil physicochemical properties in the buffer zone(Bz)of the Podocarpus National Park(PNP),in southern Ecuador.For this purpose,random samples were taken at a depth of 0-10 cm in four plots in each contrast zone and analyzed for bulk density,porosity,textural class,leaf litter depth,soil pH,as well as the contents of organic matter(SOM),soil organic carbon(SOC),total nitrogen,and available phosphorus and potassium.Results:The results indicate that the conversion of AMFs produces an increase in bulk density and a decrease in SOM,SOC,and total nitrogen contents,thus modifying soil properties,which could result in a decrease in water regulation capacity and produce an increased risk of soil erosion.This accelerates degradation processes,as well as threatens shortages of the drinking water supply.Conclusions:This study can help decision-makers to implement soil management plans in the Bz of the PNP,based on the implementation of new regulations,where the conservation of AMF is promoted.In addition,it is recommended to apply environmental restoration strategies in the anthropized areas of the AMF,as well as in the areas with exotic eucalyptus and pine plantations.展开更多
Olive(Olea europaea L.)is one of the most important and widely cultivated fruit trees,with high economic,ecological,cultural and scientific value.China began introducing and cultivating olive in the 1960s,and Yunnan P...Olive(Olea europaea L.)is one of the most important and widely cultivated fruit trees,with high economic,ecological,cultural and scientific value.China began introducing and cultivating olive in the 1960s,and Yunnan Province is one of the main growing areas.Improving the cultivation and productivity of this tree crop species is an important challenge.Olive is a typical mycotrophic species and the potential of arbuscular mycorrhizal fungi(AMF)for this plant is well recognized;nevertheless,studies of olive AMF in China are still very limited.Roots and rhizosphere soils of olive were sampled from five representative growing sites in the Yunnan Province of China to investigate the AMF colonization status in the root systems,the AMF community in the olive orchards and the edaphic factors influencing the arbuscular mycorrhizal(AM)parameters.Root samples of olive trees from different growing sites generally showed AMF colonization,suggesting that autochthonous AMF manifest a high efficiency in colonizing the roots of olive plants.The spore density on the five sites ranged from 81.6 to 350 spores per 20 g soil.Twenty-three AMF species from 9 genera were identified in total,and Glomeraceae was the dominant family.The findings of our study suggested a high AMF diversity harbored by olive growing in different areas of the Yunnan Province,Southwestern China.Furthermore,the hyphal colonization in roots positively correlated with soil pH and EC.The arbuscule colonization in olive roots negatively correlated with soil pH,EC,OM,TN,TP and AN.The spore density positively correlated with OM,TN,AN,AP and sand content.Finally,the Shannon index of AMF in the rhizosphere soil positively correlated with the clay content,but negatively correlated with soil pH,TN and silt content.The high diversity of autochthonous AMF in Yunnan is promising for screening AMF isolates for utilization in the efficient cultivation of this crop.展开更多
In arid and semi-arid regions soil salinity is a constraint for the development of plants and a threat to balance food in these soils some species are threatened with extinction. Two natural constraints drought and sa...In arid and semi-arid regions soil salinity is a constraint for the development of plants and a threat to balance food in these soils some species are threatened with extinction. Two natural constraints drought and salinity have altered the ecosystem stability, but it has always conditions more or less favorable to the existence of a spontaneous flora adapted to the climatic and edaphic stress. The aim of this study is to describe a halophyte native tree and its climatic and edaphic requirements, it is a case of Limoniastrum guyonianum. According to this survey L. guyonianum, grows well under high temperature, insolation and evaporation and low rainfall and humidity. The species tolerate the soil basic pH, salinity, calcareous and do not need the organic matter and chlorure ions There are some morphological adaptations in the L. guyonianium to the several conditions as the length of the root and cylindrical shapes of the leaves and their extraction of salt.展开更多
Biochar application to soil has been proposed as a potential management strategy to enhance soil carbon(C)sequestration,reduce greenhouse gas emission,improve soil quality,and increase crop productivity.The effects of...Biochar application to soil has been proposed as a potential management strategy to enhance soil carbon(C)sequestration,reduce greenhouse gas emission,improve soil quality,and increase crop productivity.The effects of biochar on soil microbial and enzyme activities are integrally linked to the potential of biochar in achieving these benefits.We conducted a global meta-analysis to assess the effects of biochar on soil microbial biomass C and nitrogen(N)and the activities of 12 enzymes,and identify key factors affecting those soil microbial properties using 964 data points from 72 papers.We found that biochar effects on enzyme activities vary widely with soil type,biochar property and the type of enzyme studied.Biochar significantly increased microbial biomass C(MBC)and urease,alkaline phosphatase and dehydrogenase activities by 21.7%,23.1%,25.4%and 19.8%,respectively,with no significant negative effects on any of the enzymes analyzed in this study.Biochar application was more effective in increasing MBC and enzyme activities in soils with low pH(<6.5),TC(<20 g kg^(−1)),TN(<2 g kg^(−1)),and a fine texture(including clay,clay loam and silt clay).Biochars produced at pyrolysis temperature of 350-550℃ with a high pH(>10)and low C/N ratio(<50)increased MBC and urease and dehydrogenase activities.Biochar increased MBC and N-acquisition enzyme activities in the field but not in lab incubation experiments.Urease was increased in short-term studies(within 100 days of biochar application)while alkaline phosphatase was increased in long-term studies that span more than 1 year.The increase in MBC and activities of some soil enzymes in response to biochar application with no negative effects on any hydrolytic and oxidative enzymes illustrate its potential to enhance soil quality particularly in the degraded soils with low nutrient availability and fertility due to limited soil microbial and enzymatic activities.This study also shows that biochars can be designed to achieve specific properties for enhancing microbial and enzymatic activities for specific soils.展开更多
基金supported by the "Hundred Talents Program" of the Chinese Academy of Sciences (to Jian Ni)the National Basic Research Program (No. 973) of the Ministry of Science and Technology of China(Grant No. 2013CB956704)the Scientific Research Foundation of the Education Department of Guangxi Zhuang Autonomous Region (Grant No.201106LX296)
文摘Relationships between topography,soil properties and the distribution of plant communities on two different rocky hillsides are examined in two subtropical karst forests in the Maolan National Natural Reserve,southwestern China.Surveys of two 1-ha permanent plots at each forest,and measurements of four topographic and thirteen edaphic factors on the slopes were performed.Twoway Indicator Species Analysis(TWINSPAN) and Detrended Canonical Correspondence Analysis(DCCA) were used for the classification of plant communities and for vegetation ordination with environmental variables.One hundred 10m×10m quadrats in each plot were classified into four plant community types.A clear altitudinal gradient suggested that elevation was important in community differentiation.The topography and soil explained 51.06% and 54.69% of the variability of the distribution of plant species in the two forest plots,respectively,indicating both topographic factors(eg.elevation,slope and rock-bareness rate) and edaphic factors(e.g.total P,K and exchangeable Ca) were the important drivers of the distribution of woody plant species in subtropical karst forest.However,our results suggested that topographical factors were more important than edaphic ones in affecting local plant distribution on steep slopes with extensive rock outcrops,while edaphic factors were more influential on gentle slope and relatively thick soil over rock in subtropical karst forest.Understanding relationships between vegetation and environmental factors in karst forest ecosystems would enable us to apply these findings in vegetation management strategies and restoration of forest communities.
基金To Federal University of Lavras,Foundation for the Support to the Researches in Minas Gerais(FAPEMIG),Brazilian National Council for Scientific and Technological Development(CNPq)and to Coordination for the Improvement of Higher Education Personnel(CAPES)for all the support.
文摘Our work aimed to test the hypothesis that soil microscale heterogeneity act as a community ecological driver,increasing diversity and promoting structural shifts on the Seasonally Dry Tropical Forest(SDTF)tree community.We evaluated the relationship between microscale edaphic variations and floristic–structural patterns of tree communities in a SDTF fragment located in the southern end of the Brazilian Caatinga domain.Vegetation and soil data were obtained through 27 sample units of 400 m2(20 m 920 m),within each one we measured and identified at species level all arboreal individuals with Circumference at the Breast Height greater or equal to 10 cm,and also collected the soil samples.Through the data we evaluated soil variation influence on the tree community structural and floristic patterns trough generalized linear models.Soil explained the small-scale structural and floristic variations,contributing significantly to biomass,sprouting and to floristic relationships between sample units.It was also observed a possible relation of the result with the Caatinga domain biogeographic history,due the presence of Sedimentary Caatinga species,which are not expected for the study region.Soil plays an important role in driving small-scale complexity and diversity of SDTF,but we also suggest that Caatinga biogeographic events have influence on the high heterogeneity patterns.
文摘The regulatory functions of soil are getting attention among the scientists and Soil Organic Carbon (SOC) is an important indicator of soil health. The impact of differential use of land on SOC and other edaphic properties were analysed in three important Land use land cover (LULC) system of Tripura, northeast India. Soil cores were divided into four depth profiles (0 - 10, 10 - 30, 30 - 50 and 50 - 100 cm) to observe the changes of edaphic properties into the soil depth gradient. Our results suggest that SOC in the top profile of Managed Plantation (MP) and Jhum Fellow (JF) was 51.68% and 48.55%, less than Natural Forest (NF). From 0 - 10 to 10 - 30 cm soil depth, 43.3%, 8.4% and 39.4% decrease in NF MP and JF found. Total stock of SOC (Mg C·ha<sup>﹣</sup><sup>1</sup>) was found highest in JF (121.87), followed by NF (117.12) and MP (85.34). In top profile, conversion of NF into MP and NF into JF led to 39% and 11% decrease in SOC. The significant variation in SOC stock was found among different LULC under this study (F<sub>2,12</sub> = 16.94, P ≤ 0.001). In 0 - 10 cm soil depth, maximum value of bulk density (gm·cm<sup>﹣</sup><sup>3</sup>) was found in MP (1.39) followed by JF (1.27) and NF (1.23). In top profile, significant variation was found among LULC (p < 0.001). Soil pH and moisture content significantly varied (p < 0.05) in 0 - 10, 10 - 30 and 50 - 100 cm soil depth. In contrast to that significant change in soil temperature was found at 30 - 50 cm (p < 0.001) and 50 - 100 cm (p < 0.001). It was observed that JF had highest overall SOC stock than NF and MP. Conversion of NF into MP and JF results significant loss of SOC at 0 - 10 and 10 - 30 cm depth profile. We also found that NF conversion had significant impact on the change in the soil C pool.
文摘Osyris lanceolata is heavily and illegally exploited in East Africa for its essential oils, yet little is known about its population status and ecological requirements. This study examined its population structure and environmental factors influencing its distribution in the semi-arid Karamoja sub-region, Uganda. We surveyed 388 plots (5 m radius) at different altitudes, recording life stages, stem diameters, and regeneration patterns, and analyzed soil samples. Multivariate analyses, including Canonical Correspondence Analysis (CCA), Detrended Correspondence Analysis (DCA), Non-metric Multidimensional Scaling (NMDS), and Multiple Regression Modeling (MRM), identified key environmental factors affecting its distribution. Findings show that O. lanceolata populations in Moroto, Nakapiripirit, and Amudat districts are severely degraded due to overexploitation. The species is primarily regenerating through coppicing rather than seedlings, with an exploitation intensity of 56.6%. Population densities are low, distribution is irregular, and sustainable harvesting is not viable. Soil properties, particularly Ca2+, N, P, K+, Na+, and organic matter, significantly influence its abundance. Conservation efforts should focus on identifying suitable provenances for genetic preservation and plantation establishment. Areas with at least 9 trees per hectare in Moroto, Nakapiripirit, and Amudat could serve as potential sites for ex-situ plantations. Further research should explore how biotic interactions, genetic diversity, and morphology affect oil yield and quality to support restoration, breeding, and domestication initiatives.
基金financially supported by the National Key R&D Program of China(No.2023YFF1305500)the National Natural Science Foundation of China(Nos.32022056,32101509,and 32171641)。
文摘Climate warming has intensified the global hydrological cycle,amplifying the differences in precipitation and soil moisture between arid and humid areas.Such a change under regional drought may alter nitrogen(N)and phosphorus(P)releases during litter decomposition in terrestrial ecosystems,but how these biogeochemical processes respond to drought differently between arid and humid areas remains unclear.Here,we compiled 259 and 138 paired observations(with and without drought conditions)to assess the global variations in the drought effects on N and P releases during litter decomposition between arid(aridity index<0.5)and humid(aridity index>0.5)areas.Litter N release increased under drought in both arid(0.35%)and humid(3.62%)areas,and P release decreased by 7.32%in arid areas but increased by 2.22%in humid areas under drought.These changes in N and P releases from decomposing litter were positively correlated with drought duration in arid areas,dependent on microclimate,edaphic factors,and litter quality.Our findings highlight the contrasting effects of drought on litter N and P releases between arid and humid ecosystems,and this differential influence will greatly improve our capability to evaluate and forecast nutrient cycling during litter decomposition under different precipitation patterns.
基金This work was supported by the National Research Foundation of South Africa(Grant number 81818:Biology of Cape Legumes to AMM).
文摘Aims the Cape Peninsula is a small area(471 km2)situated on the south-westernmost tip of the Core Cape Subregion(CCR)of South Africa.Within the Cape Peninsula,Fabaceae are the third most species-rich plant family(162 species)and they have the second highest number of endemic species after the Ericaceae.However,legumes are not the dominant taxa in the vegetation.they tend to show patchy distributions within the landscape and different species assemblages usually occupy particular niches at any given locality.the present study undertook to establish if edaphic factors influence legume species distribution in the Cape Peninsula and to determine the key indicator species for the different assemblages.Methods Soils from 27 legume sites,spanning all major geological substrates of the Cape Peninsula,were analysed for 31 chemical and physi-cal properties.Legume species present at each site were recorded and a presence/absence matrix was generated.Cluster analysis and discriminant function analysis(DFA)were run to group the sites based on overall similarity in edaphic characteristics and to identify the soil parameters contributing towards discriminating the groups.Canonical correspondence analysis(CCA)was used to test for a cor-relation between legume species compositions and edaphic factors.the strength of the association between legume species and site groupings based on edaphic properties was assessed using indicator species analysis.Important findings Based on similarity in overall soil characteristics,the sites formed three clusters:one comprising sites of sandstone geology,one with dune sand sites and the third cluster comprising sites of both shale and granite geologies(hereafter referred to as soil types).the DFA confirmed the distinctness of these clusters and the CCA showed a significant correlation between legume species composition and edaphic factors.the key edaphic parameters were clay content,iron(Fe),potassium(K),sulphur(S)and zinc(Zn).these findings reveal that the Cape Peninsula is edaphically heterogeneous and edaphically distinct habitats contain discrete legume species assemblages that can be distinguished by unique indicator species.Furthermore,multiple soil parameters,rather than a single parameter,are involved.therefore,edaphic factors play a significant role in driving the distribution of legume species in the Cape Peninsula and discrete legume species assemblages occupy distinct habitats.
基金This research was financed by the Natural Science Foundation of Hunan Province(No.2020JJ4296).
文摘Many studies have shown that climatic and edaphic factors influence the variations in nitrogen isotopes(δ^(15)N)in terrestrial ecosystems.However,the relative importance of co-varying climatic and edaphic controls on plantδ^(15)N remains somewhat unclear.To address this issue,regional-scale plant(L.chinensis)and soil samples were collected along a longitudinal transect across the temperate grasslands in northern China.The influences of climatic and edaphic factors on the plantδ^(15)N were disentangled using the variable importance in projection(VIP)approach.We found that the climatic and edaphic variables explained 52.4%and 31.2%,respectively,of the variation in plantδ^(15)N.The mean annual precipitation(MAP),soil N,and mean annual temperature(MAT)were the most important variables,but the soil water content(SWC),aridity index(AI),and soil clay content were also important variables.The soil pH and soil C:N ratios were identified as unimportant variables.Furthermore,a high-performance model for simulating plantδ^(15)N values was constructed based on the important variables(VIP>0.8).Further investigations should focus on the effects of the interaction between the climatic and edaphic variables on the N cycles in the temperate grasslands to provide more reliable predictions of plantδ^(15)N.
基金Strategic Priority Research Program of the Chinese Academy of Sciences (XDA05050406-3)National Natural Science Foundation of China (41201284 and 91125022)
文摘The soil properties in arid ecosystems are important determinants of vegetation distribution patterns. Soil organic carbon （SOC） content, which is closely related to soil types and the holding capacities of soil water and nutrients, exhibits complex variability in arid desert grasslands; thus, it is essentially an impact factor for the distri- bution pattern of desert grasslands. In the present study, an investigation was conducted to estimate the spatial pattern of SOC content in desert grasslands and the association with environmental factors in the diluvial-alluvial plains of northern Qilian Mountains. The results showed that the mean values of SOC ranged from 2.76 to 5.80 g/kg in the soil profiles, and decreased with soil depths. The coefficients of variation （CV） of the SOC were high （ranging from 48.83% to 94.67%）, which indicated a strong spatial variability. SOC in the desert grasslands of the study re- gion presented a regular spatial distribution, which increased gradually from the northwest to the southeast. The SOC distribution had a pattern linked to elevation, which may be related to the gradient of climate conditions. Soil type and plant community significantly affected the SOC. The SOC had a significant positive relationship with soil moisture （P〈0.05）; whereas, it had a more significant negative relationship with the soil bulk density （BD） （P〈0.01）. However, a number of the variations in the SOC could be explained not by the environmental factors involved in this analysis, but rather other factors （such as grazing activity and landscape）. The results provide important references for soil carbon storage estimation in this study region. In addition, the SOC association with environmental variables also provides a basis for a sustainable use of the limited grassland resources in the diluvial-alluvial plains of north- ern Qilian Mountains.
文摘Seven sampling sites in each of three biomes (Western Ghats, foothills of Western Ghats and west coast) of south- western India were investigated to study the distribution, abundance and ecology of pill millipedes (Arthrosphaera) and associated fauna in relation to edaphic features. Abundance and biomass of Arthrosphaera and other millipedes were the highest in Western Ghats, while earthworms were in foothills. Arthrosphaera magna and Arthrosphaera spp. were common in Western Ghats and foothills respectively, while no Arthrosphaera were found in the west coast. None of the sampling sites consisted of more than one species of Arthrosphaera. Biomass of Arthrosphaera, other millipedes and earthworms significantly differed in Western Ghats (P = 9.48 × 10-7) and foothills (P = 1.35 × 10-8), as did the biomass of species of Arthrosphaera (P = 2.76 × 10-7) between Western Ghats and foothills. Correlation analysis revealed that biomass of Arthrosphaera was significantly (P = 0.01, r = 0.45) correlated with soil organic carbon rather than other edaphic fea- tures (pH, phosphate, calcium and magnesium). Distribution pattern, abundance, biomass and ecology of Arthrosphaera of Western Ghats in relation to soil qualities were compared with millipedes of other regions of the world.
基金financially supported by the National Key Research and Development Program of China (Nos. 2016YFD0200107 and 2016YFD0300802)the Key Deployment Program of Chinese Academy of Sciences (No. KFZD-SW-108)+4 种基金the Science and Technology Services Program of Chinese Academy of Sciences (No. KFJ-STS-ZDTP-054)the Earmarked Fund for China Agriculture Research System (No. CARS-03)the National Natural Science Foundation of China (No. 41807017)the Natural Science Foundation of Jiangsu Province, China (No. BK20171106)the Open Foundation of State Key Laboratory of Soil and Sustainable Agriculture of China (No. Y20160014)
文摘Modern breeding primarily targets crop yield traits and is likely to influence root-associated microbiomes, which play significant roles in plant growth and health. The relative importance of soil and cultivar factors in shaping root-associated microbiomes of modern maize (Zea mays L.) remains uncertain. We conducted a pot experiment in a controlled environment using three soils (Mollisol, Inceptisol, and Ultisol) and four contrasting cultivars, Denghai 605, Nonghua 816, Qiaoyu 8, and Zhengdan 958, which are widely planted in China. We used 16S rRNA gene amplicon sequencing to characterize the bacterial communities in the bulk soil, rhizosphere, and endosphere. Our results showed that the four cultivars had different shoot biomass and root exudate total organic carbon and organic acid contents. The microbiomes in the bulk soil, rhizosphere, and endosphere were different. We observed apparent community divergence between soils rather than cultivars, within which edaphic factors substantially contributed to microbiome variation. Moreover, permutational multivariate analysis of variance corroborated significant contributions of soil type but not cultivar on the root-associated microbiome structure. Differential abundance analysis confirmed that each soil presented a distinct root microbiome, while network analysis indicated different co-occurrence patterns of the root microbiome among the three soils. The core root microbiome members are implicated in plant growth promotion and nutrient acquisition in the roots. In conclusion, root-associated microbiomes of modern maize are much more controlled by soil characteristics than by cultivar root exudation. Our study is anticipated to help improve breeding strategies through integrative interactions of soils, cultivars, and their associated microbiomes.
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the National Key Technology Research and Development Program of the Ministry of Science and Technology of China(2015BAD07B02).
文摘The slope aspect is one of the most critical topographic factors in mountainous areas.Little is known,however,about the eff ect of the aspect on the ectomycorrhizal(ECM)fungal community.Additionally,we know very little about the composition of ECM fungal communities associated with Quercus variabilis,which is widely distributed in East Asia.In this study,we compared the richness,community composition,and exploration types of ECM fungi associated with Q.variabilis between predominantly south-and north-facing slopes in the Taihang Mountain,North China for the fi rst time.DNA was extracted from the root tips of Q.variabilis,and Illumina MiSeq sequencing was used to identify ECM fungi.In total,168 operational taxonomic units belonging to 28 genera were detected,and the ECM community was found to be dominated by Russula,Inocybe,Tomentella,Scleroderma,and Cortinarius.Compared with the north-facing slopes,the ECM communities on the south-facing slopes had higher diversity.The community composition and exploration types were directly aff ected by the slope aspect.Also,the aspect-induced edaphic variables,such as total phosphorus,total nitrogen,total potassium,pH,and soil water content,were important sources of variation in ECM fungal richness and distributions of exploration types.Diff erent genera tended to be distributed in various slope aspects.Cenococcum,Genea,and Clavulina were signifi cantly enriched in north-facing slopes,while Geopora,Helvelosebacina,Scleroderma,Gyroporus,Astraeus,Boletus,Tricholoma,Hebeloma,Cortinarius and unclassifi ed Thelephoraceae were more abundant in south-facing slopes.Hydrophobic ECM fungi were obviously enriched in the south-facing slope,but there was no statistical diff erence between hydrophilic among the south-and north-facing slopes.Our study deepened our knowledge of the aspect-driven variation in ECM fungal communities associated with Q.variabilis.
基金funded by Vietnam Ministry of Science and Technology under Grant numberDTDL.XH.10/15Vietnam National Foundation for Science&Technology Development(106-NN.06-2016.10)International Foundation for Science(J-1-D-4602-3)。
文摘Biotic and abiotic factors control aboveground biomass(AGB)and the structure of forest ecosystems.This study analyses the variation of AGB and stand structure of evergreen broadleaved forests among six ecoregions of Vietnam.A data set of 1731-ha plots from 52 locations in undisturbed old-growth forests was developed.The results indicate that basal area and AGB are closely correlated with annual precipitation,but not with annual temperature,evaporation or hours of sunshine.Basal area and AGB are positively correlated with trees>30 cm DBH.Most areas surveyed(52.6%)in these old-growth forests had AGB of 100–200 Mg ha^-1;5.2%had AGB of 400–500 Mg ha^-1,and 0.6%had AGB of>800 Mg ha^-1.Seventy percent of the areas surveyed had stand densities of 300–600 ind.ha^-1,and 64%had basal areas of 20–40 m^2 ha^-1.Precipitation is an important factor influencing the AGB of old-growth,evergreen broadleaved forests in Vietnam.Disturbances causing the loss of large-diameter trees(e.g.,>100 cm DBH)affects AGB but may not seriously affect stand density.
基金This study is supported by University Research Fund(URF)of Quaid-i-Azam University Islamabad.
文摘Graveyards or sacred groves are often places of natural vegetation protected by spiritual believers because of their sacred beliefs and indigenous culture.A study of graveyards was conducted to determine their role in species conservation,community formation,and associated indicators and species composition using multivariate statistical approaches.It was hypothesized that variations in the age of graveyards would give rise to diverse plant communities under the impact of various edaphic and climatic factors.Quantitative ecological techniques were applied to determine various phytosociological attributes.All the data were put in MS Excel for analysis in PCORD and CANOCO softwares for cluster analysis(CA),two-way cluster analysis(TWCA),indicator species analysis and canonical correspondence analysis.CA and TWCA through Sorenson distance measurements identified five major graveyard plant communities:(1)FicusBougainvillea-Chenopodium;(2)Acacia-Datura-Convolvulus;(3)Ziziphus-Vitex-Abutilon;(4)Acacia-Lantana-Salsola;and(5)Melia-Rhazya-Peganum.Species such as Capparis decidua,Herniaria hirsuta,Salvadora oliedes and Populus euphratica were only present inside graveyards rather than outside and advocate the role of graveyards in species conservation.The impact of different environmental and climatic variables plus the age of the graveyards were also assessed for comparison of plant communities and their respective indicator species.The results indicate that higher chlorine concentration,age of graveyards,low soil electrical conductivity,lower anthropogenic activities,higher nitrogen,calcium and magnesium concentrations in the soil,and sandy soils were the strong environmental variables playing a significant role in the formation of graveyard plant communities,their associated indicators and species distribution patterns.These results could further be utilized to evaluate the role of edaphic and climatic factors,indicator species and conservation management practices at a greater scale.
基金funded by the Agricultural Science and Technology Independent Innovation Fund of Jiangsu Province of China[Grant No.CX(17)004]the National Special Fund for Forestry Scientific Research in the Public Interest(Grant No.201504406)+2 种基金Major Fund for Natural Science of Jiangsu Higher Education Institutions(Grant No.15KJA220004)Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)the Doctorate Fellowship Foundation of Nanjing Forestry University(2169125)。
文摘Arbuscular mycorrhizal fungi(AMF)form a near-ubiquitous mutualistic association with roots to help plants withstand harsh environments,and play a key role in the establishment of coastal beach plant communities.Yet little is known about the structure and composition of AMF communities on coastal beaches of eastern China.In this study,we investigated the occurrence,community composition and diversity of AMF associated with common wild plants on a coastal beach of North Jiangsu,China.Almost all of the local wild species were colonized by AMF except for Chenopodium album L.Thirty-seven AMF species were isolated from the rhizosphere belonging to 12 genera in seven families.Glomus was the dominant genus and Funneliformis mosseae the dominant species.The colonization,spore composition and diversity of AMF were strongly related to edaphic factors.Sodium(Na^(+))ions in the soil significantly and negatively affected the colonization rate by AMF and both soil Na^(+)levels and pH had a significant negative effect on AMF spore density and evenness.However,there was a significant positive correlation between species richness and total organic carbon.The results provide insights into soil factors affecting native AMF communities in coastal beach habitats which could benefit vegetation recovery and soil reclamation efforts.
基金funded by Universidad Técnica Particular de Loja(UTPL-PROY_INV_CCBIO_2020_2773 and research scholarshipⅠ-Ⅱ-ⅢCONV).
文摘Background:Andean montane forests(AMF)are biodiversity hotspots that provide fundamental hydrological services as well as carbon storage and sequestration.In recent decades,southern Ecuador AMFs have been seriously threatened by increased logging and conversion to forest plantations with exotic species.In this context,our main objective was to evaluate the effects of AMF conversion to forest plantations on soil physicochemical properties in the buffer zone(Bz)of the Podocarpus National Park(PNP),in southern Ecuador.For this purpose,random samples were taken at a depth of 0-10 cm in four plots in each contrast zone and analyzed for bulk density,porosity,textural class,leaf litter depth,soil pH,as well as the contents of organic matter(SOM),soil organic carbon(SOC),total nitrogen,and available phosphorus and potassium.Results:The results indicate that the conversion of AMFs produces an increase in bulk density and a decrease in SOM,SOC,and total nitrogen contents,thus modifying soil properties,which could result in a decrease in water regulation capacity and produce an increased risk of soil erosion.This accelerates degradation processes,as well as threatens shortages of the drinking water supply.Conclusions:This study can help decision-makers to implement soil management plans in the Bz of the PNP,based on the implementation of new regulations,where the conservation of AMF is promoted.In addition,it is recommended to apply environmental restoration strategies in the anthropized areas of the AMF,as well as in the areas with exotic eucalyptus and pine plantations.
基金supported by the National Natural Science Foundation of China(31760222)State Forestry Administration of China 948 Project“Introduction of Olive Water and Fertilizer Precise Control Technology”(2014-4-23)the“Plant Nutrition and Mycorrhiza Research”Discipline Team Building Project of Yunnan Academy of Forestry and Grassland(LKYTD-2018-6).
文摘Olive(Olea europaea L.)is one of the most important and widely cultivated fruit trees,with high economic,ecological,cultural and scientific value.China began introducing and cultivating olive in the 1960s,and Yunnan Province is one of the main growing areas.Improving the cultivation and productivity of this tree crop species is an important challenge.Olive is a typical mycotrophic species and the potential of arbuscular mycorrhizal fungi(AMF)for this plant is well recognized;nevertheless,studies of olive AMF in China are still very limited.Roots and rhizosphere soils of olive were sampled from five representative growing sites in the Yunnan Province of China to investigate the AMF colonization status in the root systems,the AMF community in the olive orchards and the edaphic factors influencing the arbuscular mycorrhizal(AM)parameters.Root samples of olive trees from different growing sites generally showed AMF colonization,suggesting that autochthonous AMF manifest a high efficiency in colonizing the roots of olive plants.The spore density on the five sites ranged from 81.6 to 350 spores per 20 g soil.Twenty-three AMF species from 9 genera were identified in total,and Glomeraceae was the dominant family.The findings of our study suggested a high AMF diversity harbored by olive growing in different areas of the Yunnan Province,Southwestern China.Furthermore,the hyphal colonization in roots positively correlated with soil pH and EC.The arbuscule colonization in olive roots negatively correlated with soil pH,EC,OM,TN,TP and AN.The spore density positively correlated with OM,TN,AN,AP and sand content.Finally,the Shannon index of AMF in the rhizosphere soil positively correlated with the clay content,but negatively correlated with soil pH,TN and silt content.The high diversity of autochthonous AMF in Yunnan is promising for screening AMF isolates for utilization in the efficient cultivation of this crop.
文摘In arid and semi-arid regions soil salinity is a constraint for the development of plants and a threat to balance food in these soils some species are threatened with extinction. Two natural constraints drought and salinity have altered the ecosystem stability, but it has always conditions more or less favorable to the existence of a spontaneous flora adapted to the climatic and edaphic stress. The aim of this study is to describe a halophyte native tree and its climatic and edaphic requirements, it is a case of Limoniastrum guyonianum. According to this survey L. guyonianum, grows well under high temperature, insolation and evaporation and low rainfall and humidity. The species tolerate the soil basic pH, salinity, calcareous and do not need the organic matter and chlorure ions There are some morphological adaptations in the L. guyonianium to the several conditions as the length of the root and cylindrical shapes of the leaves and their extraction of salt.
基金Financial support for this work was provided by the National Science and Engineering Research Council of Canada(NSERC)the Western Grains Research Foundation,Canada as scholarships to the first authorPartial funding was also provided by the Agricultural Greenhouse Gas Program(AGGP)of Agriculture and Agri-Food Canada.
文摘Biochar application to soil has been proposed as a potential management strategy to enhance soil carbon(C)sequestration,reduce greenhouse gas emission,improve soil quality,and increase crop productivity.The effects of biochar on soil microbial and enzyme activities are integrally linked to the potential of biochar in achieving these benefits.We conducted a global meta-analysis to assess the effects of biochar on soil microbial biomass C and nitrogen(N)and the activities of 12 enzymes,and identify key factors affecting those soil microbial properties using 964 data points from 72 papers.We found that biochar effects on enzyme activities vary widely with soil type,biochar property and the type of enzyme studied.Biochar significantly increased microbial biomass C(MBC)and urease,alkaline phosphatase and dehydrogenase activities by 21.7%,23.1%,25.4%and 19.8%,respectively,with no significant negative effects on any of the enzymes analyzed in this study.Biochar application was more effective in increasing MBC and enzyme activities in soils with low pH(<6.5),TC(<20 g kg^(−1)),TN(<2 g kg^(−1)),and a fine texture(including clay,clay loam and silt clay).Biochars produced at pyrolysis temperature of 350-550℃ with a high pH(>10)and low C/N ratio(<50)increased MBC and urease and dehydrogenase activities.Biochar increased MBC and N-acquisition enzyme activities in the field but not in lab incubation experiments.Urease was increased in short-term studies(within 100 days of biochar application)while alkaline phosphatase was increased in long-term studies that span more than 1 year.The increase in MBC and activities of some soil enzymes in response to biochar application with no negative effects on any hydrolytic and oxidative enzymes illustrate its potential to enhance soil quality particularly in the degraded soils with low nutrient availability and fertility due to limited soil microbial and enzymatic activities.This study also shows that biochars can be designed to achieve specific properties for enhancing microbial and enzymatic activities for specific soils.
