Regulation of carbon and nitrogen exchange rates in biological soil crusts by intrinsic and land use factors in the Sahel area

AbstractsMicrobial diversity is one of the most important drivers on ecosystem to maintain the simultaneous performance of functions (multifunctionality, MF) under climatic oscillation. However, existing studies typically consider taxonomic richness or Shannon index at the community level in which relations between diversity and functioning are not highly consistent. To disentangle the underlying linkages in real-world ecosystems, we conducted field investigation on biological soil crusts of Tibetan Plateau and evaluated multiple diversity facets (i.e., richness, evenness, and phylogeny-related trait dissimilarity) of carbon- and nitrogen-fixing functional groups (FGs). Seven crucial variables of soil functioning were also identified to calculate MF. We found that the integrated index, invoking multiple diversity components, was a stronger predictor on MF than richness. Moreover, the divergent performance of different diversity facets determined the idiosyncratic diversity effect of each FG on the MF. Namely, richness was the dominant factor for diazotrophs to maximize MF, whereas phylogenetic dissimilarity was the most important one for phototrophs. The heterogeneity among the focal FGs derived from the significant differentiation of the extent of multifunctional redundancy. Collectively, we speculated that the multifaceted diversity pattern depicts the response ability of crucial FGs by which biocrusts stabilize MF under environmental perturbation. Taken together, our results provided a perspective to bridge the gap between taxonomic and trait-based approaches for elucidating the biodiversity-ecosystem functioning relationship, and could ultimately help to boost the practices of dryland management against global change.

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Algal diversity of temperate biological soil crusts depends on land use intensity and affects phosphorus biogeochemical cycling

10.5194/bg-2017-365-rc1 ◽

2017 ◽

Author(s):

Anonymous

Keyword(s):

Land Use ◽

Biogeochemical Cycling ◽

Biological Soil Crusts ◽

Land Use Intensity ◽

Algal Diversity ◽

Soil Crusts

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Algal diversity of temperate biological soil crusts depends on land use intensity and affects phosphorus biogeochemical cycling

10.5194/bg-2017-365 ◽

2017 ◽

Cited By ~ 1

Author(s):

Karin Glaser ◽

Karen Baumannn ◽

Peter Leinweber ◽

Tatiana Mikhailyuk ◽

Ulf Karsten

Keyword(s):

Land Use ◽

Temperate Forest ◽

Algal Species ◽

Inorganic Phosphorus ◽

Biological Soil Crusts ◽

Ecological Functions ◽

Soil Crusts ◽

Disturbed Areas ◽

Management Intensity ◽

P Cycle

Abstract. Biological soil crusts (BSCs) form the most productive microbial biomass in many drylands and disturbed areas with a diverse microalgal community as key component. In temperate regions, BSCs are also common, but generally less studied, and they conduct important ecological functions, like stabilization of soil and enrichment of nutrients. Changes in land use and its intensity strongly influence biodiversity per se and it's role for ecosystem processes, particularly in regions which are densely populated like Europe. But systematic studies on land use (i.e. management intensity) gradients in temperate forests on BSCs are missing up to now. To close this gap of knowledge and enhance the understanding of management effects on BSCs, Cyanobacteria and eukaryotic microalgae as key primary producers of these communities were identified from pine and beech forests under different management regimes. Algae were identified morphologically based on enrichment cultivation and categorized in either coccal taxa, which occur typically in high diversity, or filamentous taxa, which have the potential to initiate BSC formation. In total, 52 algal species were recorded, most from the phylum Chlorophyta, followed by Streptophyta and Heterokontophyta; Cyanobacteria were much less abundant in temperate forest BSCs. The most abundant crust-initiating filamentous algae were three species of Klebsormidium (Streptophyta) a ubiquitous genus often associated with BSCs worldwide and a high tolerance to low pH. Increasing management intensity resulted in a higher richness of algae, especially the proportion of coccal algae rose. Furthermore, the proportion of inorganic phosphorus was positively correlated with the algal richness, indicating that higher diversity of algae results in a more closed P cycle. Thus, management of forests has an impact on the diversity of phototrophic organisms in BSCs, which in turn affects P cycling in the BSC.

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Supplementary material to "Algal diversity of temperate biological soil crusts depends on land use intensity and affects phosphorus biogeochemical cycling"

10.5194/bg-2017-365-supplement ◽

2017 ◽

Author(s):

Karin Glaser ◽

Karen Baumannn ◽

Peter Leinweber ◽

Tatiana Mikhailyuk ◽

Ulf Karsten

Keyword(s):

Land Use ◽

Biogeochemical Cycling ◽

Biological Soil Crusts ◽

Land Use Intensity ◽

Algal Diversity ◽

Soil Crusts ◽

Supplementary Material

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Carbon and nitrogen fixation differ between successional stages of biological soil crusts in the Colorado Plateau and Chihuahuan Desert

Journal of Arid Environments ◽

10.1016/j.jaridenv.2005.11.014 ◽

2006 ◽

Vol 66 (4) ◽

pp. 620-634 ◽

Cited By ~ 179

Author(s):

D.C. Housman ◽

H.H. Powers ◽

A.D. Collins ◽

J. Belnap

Keyword(s):

Nitrogen Fixation ◽

Chihuahuan Desert ◽

Colorado Plateau ◽

Biological Soil Crusts ◽

Carbon And Nitrogen ◽

Soil Crusts ◽

Successional Stages

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ANALYSIS OF FLOOD PRONE AREAS IN NAGAN RAYA REGENCY ACEH PROVINCE

MALAYSIAN JOURNAL OF COMPUTING ◽

10.24191/mjoc.v5i1.7805 ◽

2020 ◽

Vol 5 (1) ◽

pp. 414

Author(s):

Amsar Yunan

Keyword(s):

Land Use ◽

Spatial Data ◽

Flood Hazard ◽

Parameter Analysis ◽

Thematic Maps ◽

Aceh Province ◽

Object Area ◽

Use Factors ◽

Hazard Levels ◽

Flood Prone Areas

Maps or remote sensing can be interpreted as the process of reading using various sensors where data collected remotely can be analyzed to obtain information about the object, area or phenomenon. In this study, the author develops a flood disaster mapping information system applying overlays with scoring between the parameters. The determinant factors to provide flood hazard levels includes rainfall factors in the dasarian unit, land-use factors and land-use arbitrary factors. Of all these parameters, a scoring process will be carried out by assigning weights and values according to their respective classifications, then an overlay process will be performed using ArcGIS software. The author conducted this study in Nagan Raya Regency since this area experiences flooding annually. Framing a thematic map of flood-prone areas in Nagan Raya Regency was designed using the flood hazard method. Spatial data that has been presented in the form of thematic maps as parameters are land use maps, landform maps, and dasarian rainfall maps (per 10 daily). The design of thematic maps that are prone to flooding is done by overlapping (overlay process). In contrast, the determination of the classification is done by adding scores to each parameter, with low, medium and high hazard levels. Parameter analysis shows the level of flood vulnerability in Nagan Raya Regency of each district, namely Beutong: high 0.21%, medium 13.68%, low 86.12%. Seunagan District: high 51.17%, medium 48.83%, low 0%. Seunagan Timur District: high 10.07%, medium 46.18%, low 43.75%. Kuala Subdistrict: high 29.66%, medium 68.99%, low 1.35%. Darul Makmur District: high 8.57%, medium 63.37%, low 28.06%. From the overall results of the study, it can be concluded that the danger of flooding in Nagan Raya Regency with a level of vulnerability: high 9.92%, moderate 42.65% and low 47.43%.

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