Land use change and carbon exchange in the tropics: I. Detailed estimates for Costa Rica, Panama, Peru, and Bolivia

Abstract The biophysical response to a local change in land use is calculated using the HadGEM2-ES Earth system model. The biophysical temperature response is found to be a small residual of three large opposing flux responses: available energy, sensible heat, and latent heat. Deforestation reduces available energy, which is balanced by a reduction in heat lost via turbulent fluxes. However, the changes in turbulent heat fluxes are not simply a response to the reduction in available energy; rather, they are a direct response to land-use change, caused by reduced roughness length and, in the tropics, an increase in the Bowen ratio. Evaluation against satellite-derived observational datasets shows that in response to deforestation, the model has too much albedo-driven cooling and too little latent-heat-driven warming, leading to a large cooling bias.

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First evidence for an Amazonian insect migration in the butterfly Panacea prola (Lepidoptera: Nymphalidae)

10.1101/2020.09.01.277665 ◽

2020 ◽

Author(s):

Geoffrey Gallice ◽

Riccardo Mattea ◽

Allison Stoiser

Keyword(s):

Land Use ◽

Land Use Change ◽

Global Climate ◽

Insect Species ◽

Forest Loss ◽

Environmental Cues ◽

Mass Movements ◽

Insect Migration ◽

Nymphalid Butterfly ◽

The Tropics

ABSTRACTInsect migrations rival those of vertebrates in terms of numbers of migrating individuals and even biomass, although instances of the former are comparatively poorly documented. This is especially true in the world’s tropics, which harbor the vast majority of Earth’s insect species. Understanding these mass movements is of critical and increasing importance as global climate and land use change accelerate and interact to alter the environmental cues that underlie migration, particularly in the tropics. Here, we provide the first evidence for an insect migration for the nymphalid butterfly Panacea prola in the Amazon, the world’s largest and most biodiverse rainforest that is experiencing a shifting climate and rapid forest loss.

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Reviews and syntheses: Soil N<sub>2</sub>O and NO emissions from land use and land-use change in the tropics and subtropics: a meta-analysis

Biogeosciences ◽

10.5194/bg-12-7299-2015 ◽

2015 ◽

Vol 12 (23) ◽

pp. 7299-7313 ◽

Cited By ~ 48

Author(s):

J. van Lent ◽

K. Hergoualc'h ◽

L. V. Verchot

Keyword(s):

Land Use ◽

Land Use Change ◽

Nitrogen Availability ◽

Meta Analysis ◽

Forest Conversion ◽

N2o Emissions ◽

Emission Rates ◽

Soil N ◽

The Tropics ◽

No Emissions

Abstract. Deforestation and forest degradation in the tropics may substantially alter soil N-oxide emissions. It is particularly relevant to accurately quantify those changes to properly account for them in a REDD+ climate change mitigation scheme that provides financial incentives to reduce the emissions. With this study we provide updated land use (LU)-based emission rates (104 studies, 392 N2O and 111 NO case studies), we determine the trend and magnitude of flux changes with land-use change (LUC) using a meta-analysis approach (44 studies, 135 N2O and 37 NO cases) and evaluate biophysical drivers of N2O and NO emissions and emission changes for the tropics. The average N2O and NO emissions in intact upland tropical forest amounted to 2.0 ± 0.2 (n = 90) and 1.7 ± 0.5 (n = 36) kg N ha−1 yr−1, respectively. In agricultural soils annual N2O emissions were exponentially related to N fertilization rates and average water-filled pore space (WFPS) whereas in non-agricultural sites a Gaussian response to WFPS fit better with the observed NO and N2O emissions. The sum of soil N2O and NO fluxes and the ratio of N2O to NO increased exponentially and significantly with increasing nitrogen availability (expressed as NO3− / [NO3−+NH4+]) and WFPS, respectively; following the conceptual Hole-In-the-Pipe model. Nitrous and nitric oxide fluxes did not increase significantly overall as a result of LUC (Hedges's d of 0.11 ± 0.11 and 0.16 ± 0.19, respectively), however individual LUC trajectories or practices did. Nitrous oxide fluxes increased significantly after intact upland forest conversion to croplands (Hedges's d = 0.78 ± 0.24) and NO increased significantly following the conversion of low forest cover (secondary forest younger than 30 years, woodlands, shrublands) (Hedges's d of 0.44 ± 0.13). Forest conversion to fertilized systems significantly and highly raised both N2O and NO emission rates (Hedges's d of 1.03 ± 0.23 and 0.52 ± 0.09, respectively). Changes in nitrogen availability and WFPS were the main factors explaining changes in N2O emissions following LUC, therefore it is important that experimental designs monitor their spatio-temporal variation. Gaps in the literature on N oxide fluxes included geographical gaps (Africa, Oceania) and LU gaps (degraded forest, wetland (notably peat) forest, oil palm plantation and soy cultivation).

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The Impact of Land-Use Change on Water Resources in the Tropics: An Australian View of the Scientific Issues

Hydrology and Water Management in the Humid Tropics ◽

10.1017/cbo9780511564468.022 ◽

1993 ◽

pp. 405-413

Author(s):

P.M. Fleming

Keyword(s):

Land Use ◽

Water Resources ◽

Land Use Change ◽

The Tropics ◽

The Impact

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The effect of land use change and ecotourism on biodiversity: a case study of Manuel Antonio, Costa Rica, from 1985 to 2008

Landscape Ecology ◽

10.1007/s10980-012-9722-7 ◽

2012 ◽

Vol 27 (5) ◽

pp. 731-744 ◽

Cited By ~ 31

Author(s):

Eben N. Broadbent ◽

Angélica M. Almeyda Zambrano ◽

Rodolfo Dirzo ◽

William H. Durham ◽

Laura Driscoll ◽

...

Keyword(s):

Land Use ◽

Costa Rica ◽

Land Use Change

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Identifying Land Use Change Trajectories in Brazil’s Agricultural Frontier

Land ◽

10.3390/land9120506 ◽

2020 ◽

Vol 9 (12) ◽

pp. 506

Author(s):

Adeline M. Maciel ◽

Michelle C. A. Picoli ◽

Lubia Vinhas ◽

Gilberto Camara

Keyword(s):

Land Use ◽

Land Use Change ◽

Agricultural Practices ◽

Climate Mitigation ◽

Change Trajectories ◽

Mato Grosso ◽

Double Cropping ◽

Trajectories Of Change ◽

The Tropics ◽

Temporal Trajectory

Many of the world’s agricultural frontiers are located in the tropics. Crop and cattle expansion in these regions has a strong environmental impact. This paper examines land use and land cover transformations in Brazil, where large swaths of natural vegetation are being removed to make way for agricultural production. In Brazil, the land use dynamics are of great interest regarding the country’s sustainable development and climate mitigation actions, leading to the formulation and implantation of public policies and supply chain interventions to reduce deforestation. This paper uses temporal trajectory analysis to discuss the patterns of agricultural practices change in the different biomes of Mato Grosso State, one of Brazil’s agricultural frontiers. Taking yearly land use and cover classified images from 2001 to 2017, we identified, quantified, and spatialized areas of stability, intensification, reduction, interchange, and expansion of single and double cropping. The LUC Calculus was used as a tool to extract information about trajectories and trajectories of change. Over two decades, the land use change trajectories uncover the interplay between forest removal, cattle raising, grain production, and secondary vegetation regrowth. We observed a direct relationship between the conversion of forest areas to pasture and of pasture to agriculture areas in the Amazon portion of the Mato Grosso State in different periods. Our results enable a better understanding of trends in agricultural practices.

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