Reforestation of agricultural land in the tropics: The relative contribution of soil, living biomass and debris pools to carbon sequestration

Reduction of amount CO2 is possible by carbon sequestration to the soil. Fixation potential of EU–15 agricultural land is c. 16–19 mil t C . year−1. Amount and composition of post–harvest residues is essential for carbon soil sequestration. Long–term yield series of the most planted crops (winter wheat – Triticum aestivum, spring barley – Hordeum vulgare, corn and silage maize – Zea mays, winter rape – Brassica napus, potatoes – Solanum tuberosum, sugar beet – Beta vulgaris, alfalfa – Medicago sativa, red clover – Trifolium pratense, white mustard – Sinapis alba and fiddleneck – Phacelia tanacetifolia) in various agroecological conditions and growing technologies were used for carbon balance calculation. The carbon balances were calculated for main crop rotations of maize, sugar beet, cereal and potato production regions (24 crop rotations). The calculations were realized for following planting varieties: traditional, commercial, ecological and with higher rate of winter rape. All chosen crop rotations (except seven) have positive carbon balance in the tillage system. Amount of fixed carbon might be increases about 30% by the use of no–tillage system. Least amount of carbon is fixed by potatoes, high amount by cereals, alfalfa and sugar beet. For a short time (months) the crops sequestration of carbon is relatively high (to 4.4 t . ha−1 . year−1) or to 5.7 t . ha−1 . year−1 for no–tillage system. From the long time viewpoint (tens of years) the data of humified carbon in arable soil (max 400 kg C . ha−1 . year−1) are important. Maximal carbon deficit of chosen crop rotation is 725 kg C . year−1.

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Above- and Below-Ground Carbon Sequestration in Shelterbelt Trees in Canada: A Review

Forests ◽

10.3390/f10100922 ◽

2019 ◽

Vol 10 (10) ◽

pp. 922 ◽

Cited By ~ 3

Author(s):

Rafaella C. Mayrinck ◽

Colin P. Laroque ◽

Beyhan Y. Amichev ◽

Ken Van Rees

Keyword(s):

Climate Change ◽

Carbon Sequestration ◽

Climate Change Mitigation ◽

Agricultural Land ◽

Environmental Benefits ◽

Ghg Mitigation ◽

Mitigation Potential ◽

Sequestration Potential ◽

Below Ground ◽

Change Mitigation

Shelterbelts have been planted around the world for many reasons. Recently, due to increasing awareness of climate change risks, shelterbelt agroforestry systems have received special attention because of the environmental services they provide, including their greenhouse gas (GHG) mitigation potential. This paper aims to discuss shelterbelt history in Canada, and the environmental benefits they provide, focusing on carbon sequestration potential, above- and below-ground. Shelterbelt establishment in Canada dates back to more than a century ago, when their main use was protecting the soil, farm infrastructure and livestock from the elements. As minimal-and no-till systems have become more prevalent among agricultural producers, soil has been less exposed and less vulnerable to wind erosion, so the practice of planting and maintaining shelterbelts has declined in recent decades. In addition, as farm equipment has grown in size to meet the demands of larger landowners, shelterbelts are being removed to increase efficiency and machine maneuverability in the field. This trend of shelterbelt removal prevents shelterbelt’s climate change mitigation potential to be fully achieved. For example, in the last century, shelterbelts have sequestered 4.85 Tg C in Saskatchewan. To increase our understanding of carbon sequestration by shelterbelts, in 2013, the Government of Canada launched the Agricultural Greenhouse Gases Program (AGGP). In five years, 27 million dollars were spent supporting technologies and practices to mitigate GHG release on agricultural land, including understanding shelterbelt carbon sequestration and to encourage planting on farms. All these topics are further explained in this paper as an attempt to inform and promote shelterbelts as a climate change mitigation tool on agricultural lands.

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Evapotranspiration Partitioning in CMIP5 Models: Uncertainties and Future Projections

Journal of Climate ◽

10.1175/jcli-d-18-0583.1 ◽

2019 ◽

Vol 32 (10) ◽

pp. 2653-2671 ◽

Cited By ~ 4

Author(s):

Alexis Berg ◽

Justin Sheffield

Keyword(s):

Land Surface ◽

Stomatal Closure ◽

Surface Air Temperature ◽

Soil Evaporation ◽

Cmip5 Models ◽

Canopy Interception ◽

Area Index ◽

Near Surface ◽

Relative Contribution ◽

The Tropics

Abstract Evapotranspiration (ET) is a key process affecting terrestrial hydroclimate, as it modulates the land surface carbon, energy, and water budgets. Evapotranspiration mainly consists of the sum of three components: plant transpiration, soil evaporation, and canopy interception. Here we investigate how the partitioning of ET into these three main components is represented in CMIP5 model simulations of present and future climate. A large spread exists between models in the simulated mean present-day partitioning; even the ranking of the different components in the global mean differs between models. Differences in the simulation of the vegetation leaf area index appear to be an important cause of this spread. Although ET partitioning is not accurately known globally, existing global estimates suggest that CMIP5 models generally underestimate the relative contribution of transpiration. Differences in ET partitioning lead to differences in climate characteristics over land, such as land–atmosphere fluxes and near-surface air temperature. On the other hand, CMIP5 models simulate robust patterns of future changes in ET partitioning under global warming, notably a marked contrast between decreased transpiration and increased soil evaporation in the tropics, whereas transpiration and evaporation both increase at higher latitudes and both decrease in the dry subtropics. Idealized CMIP5 simulations from a subset of models show that the decrease in transpiration in the tropics largely reflects the stomatal closure effect of increased atmospheric CO2 on plants (despite increased vegetation from CO2 fertilization), whereas changes at higher latitudes are dominated by radiative CO2 effects, with warming and increased precipitation leading to vegetation increase and simultaneous (absolute) increases in all three ET components.

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Nitrate retention and removal in Mediterranean streams bordered by contrasting land uses: a <sup>15</sup>N tracer study

Biogeosciences ◽

10.5194/bg-6-181-2009 ◽

2009 ◽

Vol 6 (2) ◽

pp. 181-196 ◽

Cited By ~ 40

Author(s):

D. von Schiller ◽

E. Martí ◽

J. L. Riera

Keyword(s):

Agricultural Land ◽

N Cycling ◽

Urban Stream ◽

Relative Importance ◽

Transfer Velocity ◽

Nitrate Retention ◽

Relative Contribution ◽

Uptake Length ◽

Agricultural Stream ◽

Forested Stream

Abstract. We used 15N-labelled nitrate (NO3−) additions to investigate pathways of nitrogen (N) cycling at the whole-reach scale in three stream reaches with adjacent forested, urban and agricultural land areas. Our aim was to explore among-stream differences in: (i) the magnitude and relative importance of NO3− retention (i.e. assimilatory uptake) and removal (i.e. denitrification), (ii) the relative contribution of the different primary uptake compartments to NO3− retention, and (iii) the regeneration, transformation and export pathways of the retained N. Streams varied strongly in NO3− concentration, which was highest in the agricultural stream and lowest in the forested stream. The agricultural stream also showed the lowest dissolved oxygen (DO) concentration and discharge. Standing stocks of primary uptake compartments were similar among streams and dominated by detritus compartments (i.e. fine and coarse benthic organic matter). Metabolism was net heterotrophic in all streams, although the degree of heterotrophy was highest in the agricultural stream. The NO3− uptake length was shortest in the agricultural stream, intermediate in the urban stream, and longest in the forested stream. Conversely, the NO3− mass-transfer velocity and the areal NO3− uptake rate were highest in the urban stream. Denitrification was not detectable in the forested stream, but accounted for 9% and 68% of total NO3− uptake in the urban and the agricultural stream, respectively. The relative contribution of detritus compartments to NO3− assimilatory uptake was greatest in the forested and lowest in the agricultural stream. In all streams, the retained N was rapidly regenerated back to the water column. Due to a strong coupling between regeneration and nitrification, most retained N was exported from the experimental reaches in the form of NO3−. This study provides evidence of fast in-stream N cycling, although the relative importance of N retention and removal varied considerably among streams. Results suggest that permanent NO3− removal via denitrification may be enhanced over temporary NO3− retention via assimilatory uptake in heterotrophic human-altered streams characterized by high NO3− and low DO concentrations.

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Agricultural land abandonment in Mediterranean environment provides ecosystem services via soil carbon sequestration

The Science of The Total Environment ◽

10.1016/j.scitotenv.2016.10.123 ◽

2017 ◽

Vol 576 ◽

pp. 420-429 ◽

Cited By ~ 57

Author(s):

Agata Novara ◽

Luciano Gristina ◽

Giovanna Sala ◽

Antonino Galati ◽

Maria Crescimanno ◽

...

Keyword(s):

Ecosystem Services ◽

Carbon Sequestration ◽

Soil Carbon ◽

Agricultural Land ◽

Soil Carbon Sequestration ◽

Land Abandonment ◽

Mediterranean Environment

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Multi-factor controls on terrestrial carbon dynamics in urbanized areas

Biogeosciences ◽

10.5194/bg-11-7107-2014 ◽

2014 ◽

Vol 11 (24) ◽

pp. 7107-7124 ◽

Cited By ~ 19

Author(s):

C. Zhang ◽

H. Tian ◽

S. Pan ◽

G. Lockaby ◽

A. Chappelka

Keyword(s):

Carbon Sequestration ◽

Environmental Change ◽

Carbon Dynamics ◽

Individual Factors ◽

Land Conversion ◽

Terrestrial Carbon ◽

Carbon Loss ◽

Relative Contribution ◽

Urbanized Areas ◽

The Impact

Abstract. As urban land expands rapidly across the globe, much concern has been raised that urbanization may alter the terrestrial carbon cycle. Urbanization involves complex changes in land structure and multiple environmental factors. Little is known about the relative contribution of these individual factors and their interactions to the terrestrial carbon dynamics, however, which is essential for assessing the effectiveness of carbon sequestration policies focusing on urban development. This study developed a comprehensive analysis framework for quantifying relative contribution of individual factors (and their interactions) to terrestrial carbon dynamics in urbanized areas. We identified 15 factors belonging to five categories, and we applied a newly developed factorial analysis scheme to the southern United States (SUS), a rapidly urbanizing region. In all, 24 numeric experiments were designed to systematically isolate and quantify the relative contribution of individual factors. We found that the impact of land conversion was far larger than other factors. Urban managements and the overall interactive effects among major factors, however, created a carbon sink that compensated for 42% of the carbon loss in land conversion. Our findings provide valuable information for regional carbon management in the SUS: (1) it is preferable to preserve pre-urban carbon pools than to rely on the carbon sinks in urban ecosystems to compensate for the carbon loss in land conversion. (2) In forested areas, it is recommendable to improve landscape design (e.g., by arranging green spaces close to the city center) to maximize the urbanization-induced environmental change effect on carbon sequestration. Urbanization-induced environmental change will be less effective in shrubland regions. (3) Urban carbon sequestration can be significantly improved through changes in management practices, such as increased irrigation and fertilizer and targeted use of vehicles and machinery with least-associated carbon emissions.

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Relative contribution of maize and external manure amendment to soil carbon sequestration in a long-term intensive maize cropping system

Scientific Reports ◽

10.1038/srep10791 ◽

2015 ◽

Vol 5 (1) ◽

Cited By ~ 28

Author(s):

Wenju Zhang ◽

Kailou Liu ◽

Jinzhou Wang ◽

Xingfang Shao ◽

Minggang Xu ◽

...

Keyword(s):

Carbon Sequestration ◽

Soil Carbon ◽

Cropping System ◽

Soil Carbon Sequestration ◽

Relative Contribution

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Influence of Gravity Waves in the Tropical Upwelling: WACCM Simulations

Journal of the Atmospheric Sciences ◽

10.1175/jas-d-11-022.1 ◽

2011 ◽

Vol 68 (11) ◽

pp. 2599-2612 ◽

Cited By ~ 16

Author(s):

Hye-Yeong Chun ◽

Young-Ha Kim ◽

Hyun-Joo Choi ◽

Jung-Yoon Kim

Keyword(s):

Gravity Wave ◽

Gravity Waves ◽

Zonal Wind ◽

Annual Cycle ◽

Climate Model ◽

Wave Drag ◽

Flux Divergence ◽

Relative Contribution ◽

The Tropics ◽

Convective Gravity Waves

Abstract The annual cycle of tropical upwelling and contributions by planetary and gravity waves are investigated from climatological simulations using the Whole Atmosphere Community Climate Model (WACCM) including three gravity wave drag (GWD) parameterizations (orographic, nonstationary background, and convective GWD parameterizations). The tropical upwelling is estimated by the residual mean vertical velocity at 100 hPa averaged over 15°S–15°N. This is well matched with an upwelling estimate from the balance of the zonal momentum and the mass continuity. A clear annual cycle of the tropical upwelling is found, with a Northern Hemispheric (NH) wintertime maximum and NH summertime minimum determined primarily by the Eliassen–Palm flux divergence (EPD), along with a secondary contribution from the zonal wind tendency. Gravity waves increase tropical upwelling throughout the year, and of the three sources the contribution by convective gravity wave drag (CGWD) is largest in most months. The relative contribution by all three GWDs to tropical upwelling is not larger than 5%. However, when tropical upwelling is estimated by net upward mass flux between turnaround latitudes where upwelling changes downwelling, annual mean contribution by all three GWDs is up to 19% at 70 hPa by orographic and convective gravity waves with comparable magnitudes. Effects of CGWD on upwelling are investigated by conducting an additional WACCM simulation without CGWD parameterization. It was found that including CGWD parameterization increases tropical upwelling not only directly by adding CGWD forcing, but also indirectly by modulating EPD and zonal wind tendency terms in the tropics.

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Harmonized in situ JECAM datasets for agricultural land use mapping and monitoring in tropical countries

10.5194/essd-2021-125 ◽

2021 ◽

Author(s):

Audrey Jolivot ◽

Valentine Lebourgeois ◽

Mael Ameline ◽

Valérie Andriamanga ◽

Beatriz Bellón ◽

...

Keyword(s):

Land Use ◽

Agricultural Land ◽

Satellite Image ◽

Farming Systems ◽

Agricultural Land Use ◽

In Situ Data ◽

Agricultural Census ◽

Crop Types ◽

The Tropics

Abstract. The availability of crop type reference datasets for satellite image classification is very limited for complex agricultural systems as observed in developing and emerging countries. Indeed, agricultural land use is very dynamic, agricultural census are often poorly georeferenced, and crop types are difficult to photo-interpret directly from satellite imagery. In this paper, we present nine datasets collected in a standardized manner between 2013 and 2020 in seven tropical and subtropical countries within the framework of the international JECAM (Joint Experiment for Crop Assessment and Monitoring) initiative. These quality-controlled datasets are distinguished by in situ data collected at field scale by local experts, with precise geographic coordinates, and following a common protocol. Altogether, the datasets completed 27 074 polygons (20 257 crop and 6 817 non-crop) documented by detailed keywords. These datasets can be used to produce and validate agricultural land use maps in the tropics, but also, to assess the performances and the robustness of classification methods of cropland and crop types/practices in a large range of tropical farming systems. The dataset is available at https://doi.org/10.18167/DVN1/P7OLAP.

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Forest ecosystem services in the tropics: an imperfect assessment of their contribution to welfare, and environmental policy implications

REVISTA CHAPINGO SERIE CIENCIAS FORESTALES Y DEL AMBIENTE ◽

10.5154/r.rchscfa.2020.04.025 ◽

2020 ◽

Vol 27 (1) ◽

pp. 89-107

Author(s):

Martín A. López-Ramírez ◽

Keyword(s):

Land Use ◽

Ecosystem Services ◽

Forest Ecosystems ◽

Agricultural Land ◽

Natural Capital ◽

Bootstrap Method ◽

Value Added ◽

Policy Implications ◽

Production Scale ◽

The Tropics

Introduction: The specific relation between ecosystem services (ES), land use systems productivity and welfare is complex and poorly understood.Objective: To analyze the relationship between natural capital and welfare in the Agriculture, Forestry and Other Land Use (AFOLU) sector to assess Ecosystem Services contribution to agriculture, forestry and fishing value added (GDP [Gross Domestic Product]) and analyze policy implications.Materials and methods: Using land use allocation variables, forest transition model and land use GDP for 97 tropical countries, the production function of AFOLU sector was estimated using a linear regression model and a bootstrap method. The properties of the function were analyzed, and the optimal land allocation was calculated.Results and discussion: There is a direct contribution and an indirect contribution from forest ecosystems to GDP. The direct effect is manifested through the partial elasticity of forestland (P < 0.05). The indirect effect is reflected through the production scale (P < 0.05). Partial elasticity of agriculture is significantly higher than partial elasticity of forestland (P < 0.05) and production scale increases as forestland is depleted (P < 0.05). In addition, optimal land use indicates that 75 countries have forest surplus (13.2 Mkm2) and 22 forest deficit (1.5 Mkm2).Conclusions: Forest ecosystems in the AFOLU sector in the tropics produce ecosystem services for society. However, these contributions are dwarfed by agricultural land productivity.

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