Response of phosphorus fractions to land-use change followed by long-term fertilization in a sub-alpine humid soil of Qinghai–Tibet plateau

Land‐use change can have a major impact on soil properties, leading to long‐term changes in soilnutrient cycling rates and carbon storage. While a substantial amount of research has been conducted onland‐use change in tropical regions, empirical evidence of long‐term conversion of forested land toagricultural land in North America is lacking. Pervasive deforestation for the sake of agriculturethroughout much of North America is likely to have modified soil properties, with implications for theglobal climate. Here, we examined the response of physical, chemical and biological soil properties toconversion of forest to agricultural land (100 years ago) on Roebuck Farm near Perth, Ontario, Canada.Soil samples were collected at three sites from under forest and agricultural vegetative cover on bothhigh‐ and low‐lying topographic positions (12 locations in total; soil profile sampled to a depth of 40cm).Our results revealed that bulk density, pH, and nitrate concentrations were all higher in soils collectedfrom cultivate sites. In contrast, samples from forested sites exhibited greater water‐holding capacity,porosity, organic matter content, ammonia concentrations and cation exchange capacity. Many of these characteristics are linked to greater organic matter abundance and diversity in soils under forestvegetation as compared with agricultural soils. Microbial activity and Q10 values were also higher in theforest soils. While soil properties in the forest were fairly similar across topographic gradients, low‐lyingpositions under agricultural regions had higher bulk density and organic matter content than upslopepositions, suggesting significant movement of material along topographic gradients. Differences in soilproperties are attributed largely to increased compaction and loss of organic matter inputs in theagricultural system. Our results suggest that the conversion of forested land cover to agriculture landcover reduces soil quality and carbon storage, alters long‐term site productivity, and contributes toincreased atmospheric carbon dioxide concentrations.

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Warming increases carbon and nutrient fluxes from sediments in streams across land use

Biogeosciences ◽

10.5194/bg-10-1193-2013 ◽

2013 ◽

Vol 10 (2) ◽

pp. 1193-1207 ◽

Cited By ~ 24

Author(s):

S.-W. Duan ◽

S. S. Kaushal

Keyword(s):

Land Use ◽

Organic Matter ◽

Land Use Change ◽

Sulfate Reduction ◽

Organic Matter Content ◽

Soluble Reactive Phosphorus ◽

Overlying Water ◽

Sediment Fluxes ◽

Urban Sites

Abstract. Rising water temperatures due to climate and land use change can accelerate biogeochemical fluxes from sediments to streams. We investigated impacts of increased streamwater temperatures on sediment fluxes of dissolved organic carbon (DOC), nitrate, soluble reactive phosphorus (SRP) and sulfate. Experiments were conducted at 8 long-term monitoring sites across land use (forest, agricultural, suburban, and urban) at the Baltimore Ecosystem Study Long-Term Ecological Research (LTER) site in the Chesapeake Bay watershed. Over 20 yr of routine water temperature data showed substantial variation across seasons and years. Lab incubations of sediment and overlying water were conducted at 4 temperatures (4 °C, 15 °C, 25 °C, and 35 °C) for 48 h. Results indicated: (1) warming significantly increased sediment DOC fluxes to overlying water across land use but decreased DOC quality via increases in the humic-like to protein-like fractions, (2) warming consistently increased SRP fluxes from sediments to overlying water across land use, (3) warming increased sulfate fluxes from sediments to overlying water at rural/suburban sites but decreased sulfate fluxes at some urban sites likely due to sulfate reduction, and (4) nitrate fluxes showed an increasing trend with temperature at some forest and urban sites but with larger variability than SRP. Sediment fluxes of nitrate, SRP and sulfate were strongly related to watershed urbanization and organic matter content. Using relationships of sediment fluxes with temperature, we estimate a 5 °C warming would increase mean sediment fluxes of SRP, DOC and nitrate-N across streams by 0.27–1.37 g m−2 yr−1, 0.03–0.14 kg m−2 yr−1, and 0.001–0.06 kg m−2 yr−1. Understanding warming impacts on coupled biogeochemical cycles in streams (e.g., organic matter mineralization, P sorption, nitrification, denitrification, and sulfate reduction) is critical for forecasting shifts in carbon and nutrient loads in response to interactive impacts of climate and land use change.

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Soil microbial community dynamics and assembly under long-term land use change

FEMS Microbiology Ecology ◽

10.1093/femsec/fix109 ◽

2017 ◽

Vol 93 (10) ◽

Cited By ~ 23

Author(s):

Dennis Goss-Souza ◽

Lucas William Mendes ◽

Clovis Daniel Borges ◽

Dilmar Baretta ◽

Siu Mui Tsai ◽

...

Keyword(s):

Land Use ◽

Microbial Community ◽

Land Use Change ◽

Soil Microbial Community ◽

Community Dynamics ◽

Soil Microbial ◽

Microbial Community Dynamics

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Most Mexican hummingbirds lose under climate and land-use change: Long-term conservation implications

Perspectives in Ecology and Conservation ◽

10.1016/j.pecon.2021.07.001 ◽

2021 ◽

Author(s):

David A. Prieto-Torres ◽

Laura E. Nuñez Rosas ◽

Daniela Remolina Figueroa ◽

María del Coro Arizmendi

Keyword(s):

Land Use ◽

Land Use Change ◽

Conservation Implications

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Generating long-term high-resolution land-use change datasets for regional climate modeling in CORDEX domains

10.5194/egusphere-egu21-14967 ◽

2021 ◽

Author(s):

Peter Hoffmann ◽

Diana Rechid ◽

Vanessa Reinhart ◽

Christina Asmus ◽

Edouard L. Davin ◽

...

Keyword(s):

Land Use ◽

High Resolution ◽

Land Use Change ◽

Land Cover ◽

Climate Modeling ◽

Regional Climate ◽

Regional Climate Modeling ◽

Local Scale ◽

Modeling Studies

<p>Land-use and land cover (LULC) are continuously changing due to environmental changes and anthropogenic activities. Many observational and modeling studies show that LULC changes are important drivers altering land surface feedbacks and land-atmosphere exchange processes that have substantial impact on climate on the regional and local scale. Yet, most long-term regional climate modeling studies do not account for these changes. Therefore, within the WCRP CORDEX Flagship Pilot Study LUCAS (Land Use Change Across Scales) a new workflow was developed to generate high-resolution annual land cover change time series based on past reconstructions and future projections. First, the high-resolution global land cover dataset ESA-CCI LC (~300 m resolution) is aggregated and converted to a 0.1&#176; resolution, fractional plant functional type (PFT) dataset. Second, the land use change information from the land-use harmonized dataset (LUH2), provided at 0.25&#176; resolution as input for CMIP6 experiments, is translated into PFT changes employing a newly developed land use translator (LUT). The new LUT was first applied to the EURO-CORDEX domain. The resulting LULC maps for past and future - the LUCAS LUC dataset - can be applied as land use forcing to the next generation RCM simulations for downscaling CMIP6 by the EURO-CORDEX community and in the framework of FPS LUCAS. The dataset includes land cover and land management practices changes important for the regional and local scale such as urbanization and irrigation. The LUCAS LUC workflow is applied to further CORDEX domains, such as Australasia and North America. The resulting past and future land cover changes will be presented, and challenges regarding the application of the new workflow to different regions will be addressed. In addition, issues related to the implementation of the dataset into different RCMs will be discussed.</p>

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