Changing management in Scottish birch woodlands: a potential threat to local invertebrate biodiversity

AbstractThe silvicultural management of Scottish birch woodlands for timber production is replacing traditional low intensity management practices, such as domesticated livestock grazing. These new management practices involve thinning of existing woodlands to prescribed densities to maximize biomass and timber quality. Although presently infrequent, the wide scale adoption of this practice could affect invertebrate community diversity. The impact of these changes in management on Staphylinidae and Carabidae (Coleoptera) in 19 woodlands in Aberdeenshire, north-east Scotland was investigated. Grazing and logging practices were important determinants of beetle community structure. Woodland area had no effect on any measure of beetle community structure, although isolation did influence the abundance of one carabid species. Changes towards timber production forestry will influence the structure of invertebrate communities, although the scale at which this occurs will determine its effect.

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The impact of livestock grazing on the persistence of a perennial forb in a temperate Australian grassland

Pacific Conservation Biology ◽

10.1071/pc040302 ◽

2003 ◽

Vol 9 (4) ◽

pp. 302 ◽

Cited By ~ 5

Author(s):

Josh Dorrough ◽

Julian Ash

Keyword(s):

Plant Species ◽

Management Practices ◽

Livestock Grazing ◽

Grazing Management ◽

Population Growth Rates ◽

Perennial Plant ◽

South Wales ◽

Recent Occurrence ◽

The Impact

The presence of perennial plant species in grazed habitats may be an imperfect predictor of their long-term ability to persist under grazing by livestock. This is particularly the case in landscapes where grazing by livestock is a relatively recent occurrence or where management practices are leading to intensification of grazing. This paper investigates the impacts of grazing on the native perennial inter-tussock forb Leptorhynchos elongatus (Asteraceae) in grasslands on the Monaro Tablelands of New South Wales. Although the species persists in grazed habitats, exclosures indicate that current grazing management can lead to severe depletion of seed, largely due to selective removal of flowers and seed heads by livestock. A population model suggests that under current grazing management, population growth rates may be negative. Removal of livestock during flowering and seed set may assist long-term persistence of this species in grazed habitats. Despite almost 200 years of livestock grazing on the Monaro Tablelands, recent intensification of grazing management could result in the future loss of some plant species in grazed habitats.

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Spatial Distribution of Nitrogen on Grazed Karst Landscapes

The Scientific World JOURNAL ◽

10.1100/tsw.2001.374 ◽

2001 ◽

Vol 1 ◽

pp. 809-813 ◽

Cited By ~ 2

Author(s):

Douglas G. Boyer ◽

Ghiath A. Alloush

Keyword(s):

Best Management Practices ◽

Management Practices ◽

Livestock Grazing ◽

Shallow Aquifer ◽

N Leaching ◽

Agricultural Activity ◽

Fecal Matter ◽

Karst Terrain ◽

Karst Areas ◽

The Impact

The impact on water quality by agricultural activity in karst terrain is an important consideration for resource management within the Appalachian region. Karst areas comprise about 18% of the region’s land area. An estimated one-third of the region’s farms, cattle, and agricultural market value are located on karst terrain. Mean nitrate concentrations in several karst springs in southeastern West Virginia exhibit a strong linear relationship with the percentage of agriculture land cover. Development of best management practices for efficient nitrogen (N) use and reduction of outflow of N to water from karst areas requires knowledge about N dynamics on those landscapes. Water extractable NO3-N and NH4-N were measured along transects at four soil depths in two grazed sinkholes and one wooded sinkhole. Distribution of soil NO3-N and NH4-N were related to frequency of animal presence and to topographic and hydrologic redistribution of soil and fecal matter in the grazed sinkholes. Karst pastures are characterized by under drainage and funneling of water and contaminants to the shallow aquifer. Control of NO3-N leaching from karst pasture may depend on management strategies that change livestock grazing behavior in sinkholes and reduce the opportunity for water and contaminants to quickly reach sinkhole drains.

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Nonpoint Source Pollution (NPSP) Induces Structural and Functional Variation in the Fungal Community of Sediments in the Jialing River, China

10.21203/rs.3.rs-1070515/v1 ◽

2021 ◽

Author(s):

Fei Xu ◽

Lanping Zhu ◽

Jiaying Wang ◽

Yuqin Xue ◽

Kunhe Liu ◽

...

Keyword(s):

Community Structure ◽

River Basin ◽

Nonpoint Source Pollution ◽

Fungal Community ◽

River Sediments ◽

Nonpoint Source ◽

Community Diversity ◽

Jialing River ◽

Relative Abundances ◽

The Impact

Abstract Nonpoint source pollution (NPSP) from human production and life activities causes severe destruction in river basin environments. In this study, three types of sediment samples (A, NPSP tributary samples; B, non-NPSP mainstream samples; C, NPSP mainstream samples) were collected at the estuary of the NPSP tributary of the Jialing River. High-throughput sequencing of the fungal-specific internal transcribed spacer (ITS) gene region was used to identify fungal taxa. The impact of NPSP on the aquatic environment of the Jialing River was revealed by analysing the community structure, community diversity and functions of sediment fungi. The results showed that the dominant phylum of sediment fungi was Rozellomycota, followed by Ascomycota, Chytridiomycota, Basidiomycota, Mortierellomycota and Zoopagomycota (relative abundance>1%). NPSP caused a significant increase in the relative abundances of Rozellomycota, Saccharomycetes, Microascales, Saccharomycetales, Branch02 and Branch03. In addition, it caused a significant decrease in the relative abundances of Chytridiomycota, Dothideomycetes, Capnodiales, Glomerellales, Xylariales and Chaetothyriales. Moreover, NPSP caused significant changes in the physicochemical properties of Jialing River sediments, such as pH and available nitrogen (AN), which significantly increased the species richness of fungi and caused significant changes in the fungal community β-diversity (P<0.05). pH, total phosphorus (TP) and AN were the main environmental factors affecting fungal communities in Jialing River sediments. The functions of sediment fungi mainly involved three types of nutrient metabolism (symbiotrophic, pathotrophic and saprotrophic) and 75 metabolic circulation pathways. NPSP significantly improved the NONOXIPENT-PWY, PENTOSE-P-PWY, and PWY-6837 metabolic circulation pathway functions (P<0.05) and inhibited the PWY-7118, PWY-5920, and PWY-6609 metabolic circulation pathway functions (P<0.05). Hence, NPSP causes changes in the community structure and functions of sediment fungi in Jialing River and destroys the stability of the Jialing River Basin ecosystem.

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Response of ectomycorrhizal community structure to gap opening in natural and managed temperate beech-dominated forests

Canadian Journal of Forest Research ◽

10.1139/x09-072 ◽

2009 ◽

Vol 39 (7) ◽

pp. 1375-1386 ◽

Cited By ~ 30

Author(s):

Tine Grebenc ◽

Morten Christensen ◽

Urša Vilhar ◽

Matjaž Čater ◽

María P. Martín ◽

...

Keyword(s):

Community Structure ◽

Forest Management ◽

Environmental Factors ◽

Management Practices ◽

Management Practice ◽

Ecological Groups ◽

Ectomycorrhizal Community ◽

Soil Biodiversity ◽

Closed Canopy ◽

The Impact

Data on the impact of forest management practices on ectomycorrhizal community structure remains fragmentary and mainly originates from studies in northern coniferous forests. This study focuses on a comparison of ectomycorrhizal communities between canopy gaps and closed canopy areas within natural and managed beech-dominated forests at four locations in Europe. We used high resolution rDNA techniques to identify ectomycorrhiza-forming fungi and attempted to extract potential stand-, gap-, soil-, and selected environmentally derived variables by applying multivariate analysis and ordination for pooling of ecological groups of ectomycorrhiza. A significant reduction of diversity indices, ectomycorrhizal and fine root dynamics, in gaps in comparison with closed canopy stands indicates an effect of forest management practice and the high importance of maintaining and protecting natural forest areas for conservation of soil biodiversity and forest genetic resources. The ordination analysis revealed three groups of ectomycorrhiza correlated with changing environmental conditions. The litter and soil pH, number of beech seedlings, and presence of a gap had a pronounced effect on the ectomycorrhizal community. Combined analysis of ectomycorrhiza and environmental factors using correspondence analysis provided an insight into the ecological preferences of the analysed species and confirmed that environmental factors drive ectomycorrhizal community changes.

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Land conversion changes soil microbial community structure and diversity

10.21203/rs.3.rs-33038/v1 ◽

2020 ◽

Author(s):

Tong Zhang ◽

Yufei Liu ◽

Xin Sui ◽

Fuqiang Song

Keyword(s):

Land Use ◽

Community Structure ◽

Microbial Communities ◽

Soil Microbial Communities ◽

Community Diversity ◽

Forest Land ◽

Soil Microbial Community Structure ◽

Soil Microbial ◽

Significant Difference ◽

The Impact

Abstract Background: To study the impact of land-use change on soil microbial community structure and diversity in Northeast China, three typical land-use types (plough, grassland, and forest), from grassland change to forest land and grassland change to plough, in the Qiqihar region of Heilongjiang Province were taken as research objects. Methods: MiSeq high-throughput sequencing technology based on bacterial 16S rRNA and fungal ITS rRNA was used to study the above community structure of soil bacteria and fungi and to explore the relationship between soil bacteria and soil environmental factors. Results: The results showed that there was no significant difference in soil bacterial community diversity and fungal community diversity after the grassland was completely changed to forest land. The dominant bacterial phylum changed from Actinobacteria to Acidobacteria, the dominant fungal phylum changed from Ascomycetes to Basidiomycetes, and the ECM functional group increased significantly. After the grassland was changed to plough, there was no significant difference in the diversity of soil bacterial communities, and the diversity of fungal communities increased significantly. The dominant phylum changed from Actinomycetes to Proteobacteria. The dominant phylum was still Ascomycetes, and the functional groups of pathogens and parasites increased significantly. CCA showed that soil pH, MC, NO3--N, TP and AP were important factors affecting the composition of soil microbial communities, and changes in land-use patterns changed the physical and chemical properties of soils, thereby affecting the structure and diversity of microbial communities. Conclusions: Our research results clarify the impact of changes in land use on the characteristics of soil microbial communities and provide basic data on the healthy use of land.

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Population Dynamics of Chesapeake Bay Virioplankton: Total-Community Analysis by Pulsed-Field Gel Electrophoresis

Applied and Environmental Microbiology ◽

10.1128/aem.65.1.231-240.1999 ◽

1999 ◽

Vol 65 (1) ◽

pp. 231-240 ◽

Cited By ~ 135

Author(s):

K. Eric Wommack ◽

Jacques Ravel ◽

Russell T. Hill ◽

Jongsik Chun ◽

Rita R. Colwell

Keyword(s):

Population Dynamics ◽

Community Structure ◽

Viral Infection ◽

Chesapeake Bay ◽

Gel Electrophoresis ◽

Clonal Diversity ◽

Pulsed Field Gel Electrophoresis ◽

Community Diversity ◽

Pulsed Field ◽

The Impact

ABSTRACT Recognition of viruses as the most abundant component of aquatic microbial communities has stimulated investigations of the impact of viruses on bacterio- and phytoplankton host communities. From results of field studies to date, it is concluded that in most aquatic environments, a reduction in the number of bacteria on a daily basis is caused by viral infection. However, the modest amount of in situ virus-mediated mortality may be less significant than viral infection serving to maintain clonal diversity in the host communities directly, through gene transmission (i.e., transduction), and indirectly, by elimination of numerically dominant host species. If the latter mechanism for controlling community diversity prevails, then the overall structure of aquatic viral communities would be expected to change as well over short seasonal and spatial scales. To determine whether this occurs, pulsed-field gel electrophoresis (PFGE) was used to monitor the population dynamics of Chesapeake Bay virioplankton for an annual cycle (1 year). Virioplankton in water samples collected at six stations along a transect running the length of the bay were concentrated 100-fold by ultrafiltration. Viruses were further concentrated by ultracentrifugation, and the concentrated samples were embedded in agarose. PFGE analysis of virus DNA in the agarose plugs yielded several distinct bands, ranging from 50 to 300 kb. Principal-component and cluster analyses of the virus PFGE fingerprints indicated that changes in virioplankton community structure were correlated with time, geographical location, and extent of water column stratification. From the results of this study, it is concluded that, based on the dynamic nature of the Chesapeake Bay virioplankton community structure, the clonal diversity of bacterio- and phytoplankton host communities is an important component of the virus community.

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The Impact of Shariah Governance and Corporate Governance on the Risk Management Practices: Evidence from Local and Foreign Islamic Banks in Malaysia

The Journal of Muamalat and Islamic Finance Research ◽

10.33102/jmifr.v15i2.174 ◽

2018 ◽

Vol 15 (2) ◽

pp. 1-20

Author(s):

Sabri Embi ◽

Zurina Shafii

Keyword(s):

Risk Management ◽

Corporate Governance ◽

Management Practices ◽

Principal Component ◽

T Test ◽

The Body ◽

Primary Data ◽

Islamic Banks ◽

Shariah Governance ◽

The Impact

The purpose of this study is to examine the impact of Shariah governance and corporate governance (CG) on the risk management practices (RMPs) of local Islamic banks and foreign Islamic banks operating in Malaysia. The Shariah governance comprises the Shariah review (SR) and Shariah audit (SA) variables. The study also evaluates the level of RMPs, CG, SR, and SA between these two type of banks. With the aid of SPSS version 20, the items for RMPs, CG, SR, and SA were subjected to principal component analysis (PCA). From the PCA, one component or factor was extracted each for the CG, SR, and RMPs while another two factors were extracted for the SA. Primary data was collected using a self-administered survey questionnaire. The questionnaire covers four aspects ; CG, SR, SA, and RMPs. The data received from the 300 usable questionnaires were subjected to correlation and regression analyses as well as an independent t-test. The result of correlation analysis shows that all the four variables have large positive correlations with each other indicating a strong and significant relationship between them. From the regression analysis undertaken, CG, SR, and SA together explained 52.3 percent of the RMPs and CG emerged as the most influential variable that impacts the RMPs. The independent t-test carried out shows that there were significant differences in the CG and SA between the local and foreign Islamic banks. However, there were no significant differences between the two types of the bank in relation to SR and RMPs. The study has contributed to the body of knowledge and is beneficial to academicians, industry players, regulators, and other stakeholders.

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