Land-use change has a greater effect on soil diazotrophic community structure than the plant rhizosphere in acidic ferralsols in southern China

This study evaluated the effects of land-use change (L-UCH) on dung beetle community structure (Scarabaeinae) in a disturbed dry ecosystem in southern Ecuador. Five different L-UCH classes were analyzed by capturing the dung beetle species at each site using 120 pitfall traps in total. To determine dung beetle abundance and diversity at each L-UCH, a general linear model (GLM) and a redundancy analysis (RDA) were applied, which correlated environmental and edaphic conditions to the community structure. Furthermore, changes in dung-producing vertebrate fauna were examined, which varied significantly between the different L-UCH classes due to the specific anthropogenic use or level of ecosystem disturbance. The results indicated that soil organic matter, pH, potassium, and phosphorus (RDA: component 1), as well as temperature and altitude (RDA: component 2) significantly affect the abundance of beetles (GLM: p value < 0.001), besides the food availability (dung). The highest abundance and diversity (Simpson’s index > 0.4, Shannon-Wiener index > 1.10) was found in highly disturbed sites, where soils were generally more compacted, but with a greater food supply due to the introduced farm animals. At highly disturbed sites, the species Canthon balteatus, Dichotomius problematicus, and Onthphagus confuses were found specifically, which makes them useful as bio-indicators for disturbed dry forest ecosystems in southern Ecuador.

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Effects of Urbanization on Watershed Evapotranspiration and Its Components in Southern China

Water ◽

10.3390/w12030645 ◽

2020 ◽

Vol 12 (3) ◽

pp. 645 ◽

Cited By ~ 1

Author(s):

Qingzhou Zheng ◽

Lu Hao ◽

Xiaolin Huang ◽

Lei Sun ◽

Ge Sun

Keyword(s):

Land Use ◽

Land Use Change ◽

Land Surface ◽

Southern China ◽

Hydrologic Model ◽

Water Evaporation ◽

Water Yield ◽

Positive Trend ◽

Significant Downward Trend ◽

Effects Of Land Use

Understanding the effects of land use change on evapotranspiration (ET) and its partitioning to transpiration and evaporation is important for accurately evaluating the likely environmental impacts on watershed water supply, climate moderation, and other ecosystem services (e.g., carbon sequestration and biodiversity). This study used a distributed hydrologic model, MIKE SHE, to partition evapotranspiration into soil evaporation, transpiration, ponded water evaporation, and interception, and examined how the ET partitions affected the water balance in the Qinhuai River Basin from 2000 to 2013. Simulated daily ET was compared to measurements at an eddy flux research site during 2016–2017 (R2 = 0.72). Degradation in rice-wheat rotation fields and expansion of impervious surfaces impacted not only total watershed evapotranspiration, which showed a significant downward trend (p < 0.05), but also its partitioning. A significant (p < 0.01) decrease in transpiration was detected. Ponded water evaporation was the only ET partition that exhibited a significant positive trend (p < 0.05). We concluded that the reduced transpiration as a result of land use and land cover change was the primary factor driving the variation of watershed scale evapotranspiration. In addition, there was an increase in annual water yield (23%) as a response to significant reduction in ET (7%) due to a 175% expansion of urban area in the study watershed. Our study provided insights to the mechanisms of land surface–water cycle interaction and better understanding of the effects of land use change on urban micro-climate such as “urban dry island” and “urban heat island” effects.

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Rethinking the politics of land-use change: Insights from the rise of the industrial tree plantation sector in Southern China

Land Use Policy ◽

10.1016/j.landusepol.2019.104025 ◽

2019 ◽

Vol 87 ◽

pp. 104025 ◽

Cited By ~ 1

Author(s):

Yunan Xu

Keyword(s):

Land Use ◽

Land Use Change ◽

Southern China ◽

Tree Plantation

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Land use change in Amazonian Dark Earth and Acrisol: Responses of organic carbon, organic matter composition and microbial carbon utilisation

10.5194/egusphere-egu2020-19752 ◽

2020 ◽

Author(s):

Klaus Jarosch ◽

Luis Carlos Colocho Hurtarte ◽

Konstantin Gavazov ◽

Aleksander Westphal Muniz ◽

Christoph Müller ◽

...

Keyword(s):

Land Use ◽

Organic Matter ◽

Community Structure ◽

Microbial Community ◽

Organic Carbon ◽

Land Use Change ◽

Microbial Community Structure ◽

Secondary Forest ◽

Soil Types ◽

Amazonian Dark Earth

The conversion of tropical forest for cassava cultivation is widely known to decrease the soil organic matter (OM) and nutrient contents of highly weathered soils in the tropics. Amazonian Dark Earth (ADE) might be affected less due to their historical anthropogenic amelioration with e.g. charcoal, ceramics and bones, leading to higher soil OM and nutrient concentrations. In this study, we analysed the effect of land use change on the OM dynamics and its composition under tropical conditions, using ADE and an adjacent Acrisol (ACR) as model systems. Soil samples were obtained south of Manaus (Brazil), from a secondary forest and an adjacently located 40-year-old cassava plantation. The land use change induced a severe decrease of organic carbon (OC) concentrations in ADE (from 35 to 15&#160;g&#160;OC&#160;kg&#8209;1) while OC in the adjacent ACR was less affected (18 to 16&#160;g&#160;OC&#160;kg&#8209;1). Soils were analysed by 13C NMR spectroscopy to obtain information on how the conversion of secondary forest to cassava affected the chemical composition of OM. Our results show that land use change induces differences in the OM composition: The OM in ADE changes to a more decomposed state (increase of alkyl:O/N-alkyl ratio) whereas the OM in ACR changes to a less decomposed state (decrease of alkyl:O/N-alkyl ratio). According to a molecular mixing model, land use change influenced mostly the proportion of lipids, which might be related with a change of the plant input. The incubation of the soils with 13C glucose enabled resolving how soil microorganisms were affected by land use change. In both soil types ADE and ACR, land use change caused a reduction of the total 13C glucose respiration by approximately one third in a 7-days incubation, implying lower microbial activity. Microorganisms in both soil types appear to be more readily active in soils under forest, since we observed a distinct lag time between 13C glucose addition and respiration under cassava planation. This indicated differences in microbial community structure, which we will assess further by determining the 13C label uptake by the microbial biomass and the microbial community structure using 13C PLFA analysis. Preliminary results from synchrotron-based STXM demonstrate a distinct arrangement of OM at fine-sized charcoal-particle interfaces. Samples of soils receiving 13C label will be further analysed by NanoSIMS with the hypothesis that charcoal interfaces foster nutrient dynamics at the microscale. Despite the high loss of OC in the ameliorated ADE through land use change, the remaining OM might improve the nutrient availability thanks to charcoal interactions compared to the ACR. Our results contribute to a better understanding of the sensitivity of OM upon land use change and how the microbial community is responding to land use change in highly weathered tropical soils.

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Impacts of Land Use Change on the Regional Climate: A Structural Equation Modeling Study in Southern China

Advances in Meteorology ◽

10.1155/2015/563673 ◽

2015 ◽

Vol 2015 ◽

pp. 1-10 ◽

Cited By ~ 3

Author(s):

Zhanqi Wang ◽

Bingqing Li ◽

Jun Yang

Keyword(s):

Climate Change ◽

Land Use ◽

Land Use Change ◽

Structural Equation ◽

Southern China ◽

Regional Climate ◽

Regional Climate Change ◽

Equation Modeling ◽

Surrounding Area ◽

Rapid Urbanization

With the frequent human activities operating on the earth, the impacts of land use change on the regional climate are increasingly perceptible. Under the background of the rapid urbanization, understanding the impacts of land use change on the regional climate change is vital and significant. In this study, we investigated the relationships between land use change and regional climate change through a structural equation model. Southern China was selected as the study area for its rapid urbanization and different structure of land use among its counties. The results indicate that the path coefficients of “vegetation,” “Urban and surrounding area,” and “other” to “climate” are −0.42, 0.20, and 0.46, respectively. Adding vegetation area is the main method to mitigate regional climate change. Urban and surrounding area and other areas influence regional climate by increasing temperature and precipitation to a certain extent. Adding grassland and forestry, restraining sprawl of built-up area, and making the most use of unused land are efficient ways to mitigate the regional climate change in Southern China. The results can provide feasible recommendations to land use policy maker.

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Relative Importance of Land Use and Climate Change on Hydrology in Agricultural Watershed of Southern China

Sustainability ◽

10.3390/su12166423 ◽

2020 ◽

Vol 12 (16) ◽

pp. 6423

Author(s):

Lanhua Luo ◽

Qing Zhou ◽

Hong S. He ◽

Liangxia Duan ◽

Gaoling Zhang ◽

...

Keyword(s):

Climate Change ◽

Land Use ◽

Land Use Change ◽

River Basin ◽

Laboratory Experiments ◽

Southern China ◽

Swat Model ◽

Efficiency Coefficient ◽

Soil Database ◽

The Impact

Quantitative assessment of the impact of land use and climate change on hydrological processes is of great importance to water resources planning and management. The main objective of this study was to quantitatively assess the response of runoff to land use and climate change in the Zhengshui River Basin of Southern China, a heavily used agricultural basin. The Soil and Water Assessment Tool (SWAT) was used to simulate the river runoff for the Zhengshui River Basin. Specifically, a soil database was constructed based on field work and laboratory experiments as input data for the SWAT model. Following SWAT calibration, simulated results were compared with observed runoff data for the period 2006 to 2013. The Nash-Sutcliffe Efficiency Coefficient (NSE) and the correlation coefficient (R2) for the comparisons were greater than 0.80, indicating close agreement. The calibrated models were applied to simulate monthly runoff in 1990 and 2010 for four scenarios with different land use and climate conditions. Climate change played a dominant role affecting runoff of this basin, with climate change decreasing simulated runoff by −100.22% in 2010 compared to that of 1990, land use change increasing runoff in this basin by 0.20% and the combination of climate change and land use change decreasing runoff by 60.8m3/s. The decrease of forestland area and the corresponding increase of developed land and cultivated land area led to the small increase in runoff associated with land use change. The influence of precipitation on runoff was greater than temperature. The soil database used to model runoff with the SWAT model for the basin was constructed using a combination of field investigation and laboratory experiments, and simulations of runoff based on that new soil database more closely matched observations of runoff than simulations based on the generic Harmonized World Soil Database (HWSD). This study may provide an important reference to guide management decisions for this and similar watersheds.

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Future forest dynamics under climate change, land use change, and harvest in subtropical forests in Southern China

Landscape Ecology ◽

10.1007/s10980-019-00809-8 ◽

2019 ◽

Vol 34 (4) ◽

pp. 843-863 ◽

Cited By ~ 8

Author(s):

Zhuo Wu ◽

Erfu Dai ◽

Zhifeng Wu ◽

Meizhen Lin

Keyword(s):

Climate Change ◽

Land Use ◽

Land Use Change ◽

Forest Dynamics ◽

Southern China ◽

Subtropical Forests

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Topographic Dependence of Cropland Transformation in China during the First Decade of the 21st Century

The Scientific World JOURNAL ◽

10.1155/2013/303685 ◽

2013 ◽

Vol 2013 ◽

pp. 1-12 ◽

Cited By ~ 4

Author(s):

Yuejiao Li ◽

Xiaohuan Yang ◽

Wenli Long

Keyword(s):

Land Use ◽

Land Use Change ◽

21St Century ◽

Land Reclamation ◽

Southern China ◽

Critical Role ◽

Northern China ◽

Limiting Factor ◽

Spatial Statistical Analysis ◽

Level Of Economic Development

Terrain plays a critical role in the selection of cropland. As a physical and geographical element of the landscape, terrain is an important limiting factor in land use change and has a strong influence on human activities. The objectives of this study are to investigate the topographic characteristics of cropland-related transformations in China during the first decade of the 21st century and to explore the implications of land use change as it relates to securing a national food supply. A 2010 satellite-based land use dataset and the DEM data were used to conduct spatial statistical analysis using altitude, slope, and fragmentation data. The results showed the following. (1) As the urbanization and industrialization of China occur, and China attempts to replace this occupied cropland with newly reclaimed cropland, the topography of the most recently reclaimed cropland has been more poorly suited to farming than the topography of the occupied cropland it replaces in most provinces. (2) The area of occupied cropland was much larger than of those reclaimed; the qualities of occupied and reclaimed cropland were significantly different. (3) Land reclamation mainly occurred in northern China, instead of in southern China, which has a higher level of economic development. Our findings imply that the potential area available for cropland production may be limited.

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