scholarly journals Modeling gas exchange and biomass production in West African Sahelian and Sudanian ecological zones

2021 ◽  
Vol 14 (6) ◽  
pp. 3789-3812
Author(s):  
Jaber Rahimi ◽  
Expedit Evariste Ago ◽  
Augustine Ayantunde ◽  
Sina Berger ◽  
Jan Bogaert ◽  
...  
Keyword(s):  
Land Use ◽  
West Africa ◽  
Aboveground Biomass ◽  
Carbon Stocks ◽  
West African ◽  
Biogeochemical Model ◽  
Area Index ◽  
Wide Range ◽  
The Impact ◽  
Mean Square Errors

Abstract. West African Sahelian and Sudanian ecosystems provide essential services to people and also play a significant role within the global carbon cycle. However, climate and land use are dynamically changing, and uncertainty remains with respect to how these changes will affect the potential of these regions to provide food and fodder resources or how they will affect the biosphere–atmosphere exchange of CO2. In this study, we investigate the capacity of a process-based biogeochemical model, LandscapeDNDC, to simulate net ecosystem exchange (NEE) and aboveground biomass of typical managed and natural Sahelian and Sudanian savanna ecosystems. In order to improve the simulation of phenology, we introduced soil-water availability as a common driver of foliage development and productivity for all of these systems. The new approach was tested by using a sample of sites (calibration sites) that provided NEE from flux tower observations as well as leaf area index data from satellite images (MODIS, MODerate resolution Imaging Spectroradiometer). For assessing the simulation accuracy, we applied the calibrated model to 42 additional sites (validation sites) across West Africa for which measured aboveground biomass data were available. The model showed good performance regarding biomass of crops, grass, or trees, yielding correlation coefficients of 0.82, 0.94, and 0.77 and root-mean-square errors of 0.15, 0.22, and 0.12 kg m−2, respectively. The simulations indicate aboveground carbon stocks of up to 0.17, 0.33, and 0.54 kg C ha−1 m−2 for agricultural, savanna grasslands, and savanna mixed tree–grassland sites, respectively. Carbon stocks and exchange rates were particularly correlated with the abundance of trees, and grass biomass and crop yields were higher under more humid climatic conditions. Our study shows the capability of LandscapeDNDC to accurately simulate carbon balances in natural and agricultural ecosystems in semiarid West Africa under a wide range of conditions; thus, the model could be used to assess the impact of land-use and climate change on the regional biomass productivity.

scholarly journals Modelling Gas Exchange and Biomass Production in West African Sahelian and Sudanian Ecological Zones

2021 ◽  
Author(s):  
Jaber Rahimi ◽  
Expedit Evariste Ago ◽  
Augustine Ayantunde ◽  
Sina Berger ◽  
Jan Bogaert ◽  
...  
Keyword(s):  
Land Use ◽  
West Africa ◽  
Soil Water ◽  
Aboveground Biomass ◽  
Carbon Stocks ◽  
West African ◽  
Biogeochemical Model ◽  
Area Index ◽  
Wide Range ◽  
The Impact

Abstract. West African Sahelian and Sudanian ecosystems are providing essential services to people and also play a significant role within the global carbon cycle. However, climate and land use are dynamically changing and it remains uncertain how these changes will affect the potential of these regions for providing food and fodder resources or the biosphere-atmosphere exchange of CO2. In this study, we investigate the capacity of a process-based biogeochemical model, LandscapeDNDC, to simulate net ecosystem exchange (NEE) and aboveground biomass of typical managed and natural Sahelian and Sudanian savanna ecosystems. We tested the model for various sites with different proportions of trees and grasses, as well as for the most typical arable cropping systems of the region. In order to describe the phenological development with a common parameterization across all ecosystem types, we introduced soil-water availability in addition to temperature as a driver as seasonal soil water-shortage is a common feature for all these systems. The new approach was tested by using a sample of sites (calibration sites) that provided NEE from flux tower observations and leaf area index data from satellite images (MODIS). For assessing the simulation accuracy, we applied the calibrated model to 42 additional sites (validation sites) across West Africa for which measured aboveground biomass data were available. The model showed a good performance regarding simulated biomass development. Overall, the comparison of simulated and observed biomass at sites with a dominating land cover of crops, grass or trees yielded correlation coefficients of 0.82, 0.94, and 0.77 and the Root Mean Square Error of 0.15, 0.22, and 0.12 kg m−2, respectively. In absolute terms, the model results indicate above-ground carbon stocks up to 1733, 3291, and 5377 kg C ha−1 yr−1 for agricultural, savanna grasslands, and savanna mixed tree-grassland sites. Carbon stocks as well as exchange rates correlated in particular with the abundance of trees. The simulations indicate higher grass biomass and crop yields under more humid climatic conditions as can be found in the Sudanian savanna region. Our study shows the capability of LandscapeDNDC to accurately simulate carbon balances in natural and agricultural ecosystems in semi-arid West Africa under a wide range of conditions, so that it might be used to assess the impact of land-use and climate change on the regional biomass productivity.

scholarly journals Facilitating spatially-explicit assessments of ecosystem service delivery to support land use planning

One Ecosystem ◽  
2020 ◽  
Vol 5 ◽  
Author(s):  
Dirk Vrebos ◽  
Jan Staes ◽  
Steven Broekx ◽  
Leo de Nocker ◽  
Karen Gabriels ◽  
...  
Keyword(s):  
Decision Making ◽  
Land Use ◽  
Ecosystem Services ◽  
Ecosystem Service ◽  
Assessment Tools ◽  
Spatially Explicit ◽  
Practical Implementation ◽  
Time Investment ◽  
Wide Range ◽  
The Impact

Since the early 2000s, there have been substantial efforts to transform the concept of ecosystem services into practice. Spatial assessment tools are being developed to evaluate the impact of spatial planning on a wide range of ecosystem services. However, the actual implementation in decision-making remains limited. To improve implementation, tools that are tailored to local conditions can provide accurate, meaningful information. Instead of a generic and widely-applicable tool, we developed a regional, spatially-explicit tool (ECOPLAN-SE) to analyse the impact of changes in land use on the delivery of 18 ecosystem services in Flanders (Belgium). The tool incorporates ecosystem services relevant to policy-makers and managers and makes use of detailed local data and knowledge. By providing an easy-to-use tool, including the required spatial geodatasets, time investment and the learning curve remain limited for the user. With this tool, constraints to implement ecosystem service assessments in local decision-making are drastically reduced. We believe that region-specific decision support systems, like ECOPLAN-SE, are indispensable intermediates between the conceptual ecosystem service frameworks and the practical implementation in planning processes.

scholarly journals A Synoptic Review of Forestry and Forest Products Trade and Production in Africa- The Case of Wood and Non-Wood Forest Products in West Africa

2022 ◽  
Author(s):  
John Adekunle Adesina ◽  
Zhu Jiangang ◽  
Tang Xiaolan
Keyword(s):  
West Africa ◽  
Natural Capital ◽  
Natural Habitat ◽  
Forest Products ◽  
West African ◽  
Warning Signs ◽  
Low Carbon ◽  
Forest Reserves ◽  
Impact Reduction ◽  
The Impact

According to this study, approximately half of Africa's forests are utilized primarily or partially for the production of wood and non-wood commodities. Aims to evaluate Africa's forestry and forest products, namely Wood Forest Products (WFPs) and Non-wood Forest Products (NWFPs) in the sixteen (16) West African countries. While adhering to the following guidelines: wood extraction and preparation, analyzing wood primarily used as an energy source in Africa, identifying non-wood forest products in Africa, the state of export, trade, and customs procedures in West Africa, and examining the role of forests and forest stakeholders in Africa's low-carbon economy transition. An exploratory literature review of selected wood forest products and non-wood forest products (plants and animals) in West Africa identifying the country, the natural land area with the natural habitat issues of the forest, the species most harvested and traded in the West African sub-region. The study reemphasized some government legislation, policies, and market trade failures and limitations while also stating that trees may help in the low-carbon revolution through interventions aimed at maintaining, improving, and restoring natural capital have demonstrated that high environmental requirements of sustainable forest management (SFM) may be met in both natural and planted forests. The study identified a systematic assessment of the most common forest products (wood and non-wood forest products) considering the available data on the national forest reserves of the selected countries in West Africa. The study also revealed the need for biodiversity conservation of the available forest reserves to help mitigate the impact of global warming targeting the United Nation’s Sustainable Development Goal 13- Climate Action. Which is focused on integrating climate change mitigation, adaptation, impact reduction, and early warning signs into the national policies, improving forest planning and management education, awareness-raising, and institutional capacity within the sub-region.

scholarly journals Ecosystem Service Multifunctionality: Decline and Recovery Pathways in the Amazon and Chocó Lowland Rainforests

2020 ◽  
Vol 12 (18) ◽  
pp. 7786 ◽  
Author(s):  
Paul Eguiguren ◽  
Tatiana Ojeda Luna ◽  
Bolier Torres ◽  
Melvin Lippe ◽  
Sven Günter
Keyword(s):  
Land Use ◽  
Ecosystem Service ◽  
Agroforestry Systems ◽  
Carbon Stocks ◽  
Land Use Transition ◽  
Trade Offs ◽  
Successional Forests ◽  
Post Harvesting ◽  
Recovery Pathways ◽  
The Impact

The balance between the supply of multiple ecosystem services (ES) and the fulfillment of society demands is a challenge, especially in the tropics where different land use transition phases emerge. These phases are characterized by either a decline (from intact old-growth to logged forests) or a recovery of ES (successional forests, plantations, and agroforestry systems). This highlights the importance of ecosystem service multifunctionality (M) assessments across these land use transition phases as a basis for forest management and conservation. We analyzed synergies and trade-offs of ES to identify potential umbrella ES. We also evaluated the impact of logging activities in the decline of ES and M, and the influence of three recovery phases in the supply of ES and M. We installed 156 inventory plots (1600 m2) in the Ecuadorian Central Amazon and the Chocó. We estimated indicators for provisioning, regulating, supporting services and biodiversity. M indicator was estimated using the multifunctional average approach. Our results show that above-ground carbon stocks can be considered as an umbrella service as it presented high synergetic relations with M and various ES. We observed that logging activities caused a decline of 16–18% on M, with high impacts for timber volume and above-ground carbon stocks, calling for more sustainable practices with stricter post-harvesting control to avoid a higher depletion of ES and M. From the recovery phases it is evident that, successional forests offer the highest level of M, evidencing high potential to recover multiple ES after human disturbance.

scholarly journals STRATIFIKASI SIMPANAN KARBON DIATAS PERMUKAAN TANAH PADA LAHAN GAMBUT PASANG SURUT DAN LEBAK

2018 ◽  
Vol 16 (3) ◽  
Author(s):  
Siti Nur Zakiah ◽  
Nur Wakhid ◽  
Dedi Nursyamsi
Keyword(s):  
Land Use ◽  
Fresh Water ◽  
Plant Density ◽  
Land Use Changes ◽  
Carbon Stocks ◽  
Technology Applications ◽  
C Stock ◽  
Vegetation Carbon ◽  
The Impact ◽  
Non Destructive

The carbon stored in peatlands is huge not only from soil but also from vegetation. Carbon stocks can decrease when there are human activities such as land use changes. Measuring and monitoring carbon stocks are necessary as the basis for assessment of the impact of land management technology applications to conservation and carbon emissions associated with sustainable management system of peatland. The purpose of this study was to determine the stratification of above ground C-stock in tidal peatland and fresh water swampland. Above ground C-stock stratification based on the types of vegetation. The stratification was conducted to distinguish vegetation conditions based on the volume of biomass and carbon content in an observation plot. The measurement of above ground C-stock was carried out by destructive and non destructive refers to Hairiah K and Rahayu (2007), after that the estimation of carbon stockswas conducted on tidal peatland (land use rubber + pineapple, rubber folk and shrubs) and peat in fresh water swampland (land use rubber 4-5 years and 2-3 years). The results showed that the types of vegetation, plant density and management affect of carbon stocks. Carbon stocks in tree vegetation are higher than shrubs. The high of plant density affects the sunlight used for photosynthesis, through photosynthesis, CO2 is absorbed and converted by plants into organic carbon in the form of biomass. Arrangement and maintenance of the plant affects the storage of carbon in a land use.

scholarly journals The impact of long dry periods on the aboveground biomass in tropical forests: 20 years of monitoring

2020 ◽  
Author(s):  
Milton Serpa de Meira-Junior ◽  
José Roberto Rodrigues Pinto ◽  
Natália Oliveira Ramos ◽  
Eder Pereira Miguel ◽  
Ricardo de Oliveira Gaspar ◽  
...  
Keyword(s):  
Tropical Forests ◽  
Aboveground Biomass ◽  
Carbon Stocks ◽  
Stem Density ◽  
Biomass Carbon ◽  
Neotropical Forests ◽  
Aboveground Carbon ◽  
Large Trees ◽  
The Impact

Abstract Background Long-term studies of community and population dynamics indicate that abrupt disturbances often catalyse changes in vegetation and carbon stocks. These disturbances include the opening of clearings, flooding, rainfall seasonality, and drought, as well as fire and direct human disturbance. Such events may be super-imposed on longer-term trends in disturbance, such as those associated with climate change (heating, drying), as well as resources. Intact neotropical forests have recently experienced increased drought frequency and fire, on top of pervasive increases in atmospheric CO2 concentrations, but we lack long-term records of responses to such changes especially in the critical transitional areas at the interface of forest and savanna biomes. Here, we present results from 20 years monitoring a valley forest (moist tropical forest outlier) in central Brazil. The forest has experienced multiple drought events and includes plots which have and which have not experienced fire. We focus on how forest structure (stem density and aboveground biomass carbon) and dynamics (stem and biomass mortality and recruitment) have responded to these disturbance regimes. ResultsOverall, the biomass carbon stock increased due to the growth of the trees already present in the forest, without any increase in the overall number of tree stems. Over time, both recruitment and especially mortality of trees tended to increase, and periods of prolonged drought in particular resulted in increased mortality rates of larger trees. This increased mortality was in turn responsible for a decline in aboveground carbon toward the end of the monitoring period. Fire in 2010, which occurred in only some of our plots, tended to exacerbate the trends of increasing mortality and losses of biomass carbon. Conclusion Prolonged droughts influence the mortality of large trees, leading to a decline in aboveground carbon stocks. Here, and in other neotropical forests, recent droughts are capable of shutting down and reversing biomass carbon sinks. These new results add to evidence that anthropogenic climate changes are already adversely impacting tropical forests.

scholarly journals Improved model of isoprene emissions in Africa using OMI satellite observations of formaldehyde: implications for oxidants and particulate matter

2014 ◽  
Vol 14 (5) ◽  
pp. 6951-6979
Author(s):  
E. A. Marais ◽  
D. J. Jacob ◽  
A. Guenther ◽  
K. Chance ◽  
T. P. Kurosu ◽  
...  
Keyword(s):  
Particulate Matter ◽  
West Africa ◽  
Surface Ozone ◽  
Satellite Observations ◽  
Atmospheric Composition ◽  
Arid Environments ◽  
Emission Model ◽  
Area Index ◽  
Isoprene Emission ◽  
The Impact

Abstract. We use a 2005–2009 record of isoprene emissions over Africa derived from OMI satellite observations of formaldehyde (HCHO) to better understand the factors controlling isoprene emission on the scale of the continent and evaluate the impact of isoprene emissions on atmospheric composition in Africa. OMI-derived isoprene emissions show large seasonality over savannas driven by temperature and leaf area index (LAI), and much weaker seasonality over equatorial forests driven by temperature. The commonly used MEGAN (version 2.1) global isoprene emission model reproduces this seasonality but is biased high, particularly for equatorial forests, when compared to OMI and relaxed-eddy accumulation measurements. Isoprene emissions in MEGAN are computed as the product of an emission factor Eo, LAI, and activity factors dependent on environmental variables. We use the OMI-derived emissions to provide improved estimates of Eo that are in good agreement with direct leaf measurements from field campaigns (r = 0.55, bias = −19%). The largest downward corrections to MEGAN Eo values are for equatorial forests and semi-arid environments, and this is consistent with latitudinal transects of isoprene over West Africa from the AMMA aircraft campaign. Total emission of isoprene in Africa is estimated to be 77 Tg C a−1, compared to 104 Tg C a−1 in MEGAN. Simulations with the GEOS-Chem oxidant-aerosol model suggest that isoprene emissions increase mean surface ozone in West Africa by up to 8 ppbv, and particulate matter by up to 1.5 μg m−3, due to coupling with anthropogenic influences.

The Impact of Land Use on Soil Properties and Structure of Ecosystem Carbon Stocks in the Middle Taiga Subzone of Karelia

2021 ◽  
Vol 54 (11) ◽  
pp. 1756-1769
Author(s):  
I. A. Dubrovina ◽  
E. V. Moshkina ◽  
V. A. Sidorova ◽  
A. V. Tuyunen ◽  
A. Yu. Karpechko ◽  
...  
Keyword(s):  
Land Use ◽  
Soil Properties ◽  
Carbon Stocks ◽  
Middle Taiga ◽  
Middle Taiga Subzone ◽  
Ecosystem Carbon ◽  
Ecosystem Carbon Stocks ◽  
The Impact

Savanna woody plants and their provision of food resources to bees in southern Burkina Faso, West Africa

2020 ◽  
Vol 5 (1) ◽  
pp. 14-23 ◽  
Author(s):  
Coulibaly Drissa ◽  
Yalamoussa Tuo ◽  
Mouhamadou Koné ◽  
Larba Hubert Balima ◽  
Souleymane Konaté ◽  
...  
Keyword(s):  
Land Use ◽  
West Africa ◽  
Plant Species ◽  
Woody Plant ◽  
Food Resources ◽  
Native Plant ◽  
Natural Habitats ◽  
Woody Plant Species ◽  
Wide Range ◽  
Pollen Species

West African savanna ecosystems and biodiversity are severely threatened by intensified land use and increasing degradation of natural habitats. Despite the importance of bees for pollinating crops and native plant species little information is available regarding the importance of savanna woody plant species to provide bees with food resources. Flora inventories were carried out on 48 subplots laid out across three land use types. The number of bee morphospecies and their abundance as flower visitors were recorded from inflorescences of plants during the different flowering periods. Out of a total diversity of 82 woody plant species, 53 species (64.63%) from 38 genera and 21 families were melliferous. These plants were visited by bees for foraging nectar and/or pollen. Species of the Combretaceae family were the most visited by bees in terms of individuals (53.85%). Combretum glutinosum alone accounted for 36% of visits. More than half of the melliferous plants (50.94%) were visited for both nectar and pollen. About 32.08% of plants were visited for nectar only (32.08%), while 16.98% were visited for pollen only (16.98%). The majority of savanna plants are flowering in the dry season, but few flowering species can be found throughout the whole year. Savanna woody plant species constitute important food resources for bees, therefore providing a wide range of applications for the development of beekeeping activities in the Sudanian region of West Africa.

Sign in / Sign up

Export Citation Format

Share Document