Mixed-species allometric equations and estimation of aboveground biomass and carbon stocks in restoring degraded landscape in northern Ethiopia

Mokria M, Mekuria W, Gebrekirstos A, Aynekulu E, Belay B, Gashaw T, Bräuning A (2018)

Publication Status: Published

Publication Type: Journal article

Publication year: 2018

Journal

Environmental Research Letters Institute of Physics: Open Access Journals / Institute of Physics (IoP)

Publisher: IOP PUBLISHING LTD

Book Volume: 13

Journal Issue: 2

DOI: 10.1088/1748-9326/aaa495

Abstract

Accurate biomass estimation is critical to quantify the changes in biomass and carbon stocks following the restoration of degraded landscapes. However, there is lack of site-specific allometric equations for the estimation of aboveground biomass (AGB), which consequently limits our understanding of the contributions of restoration efforts in mitigating climate change. This study was conducted in northwestern Ethiopia to develop a multi-species allometric equation and investigate the spatial and temporal variation of C-stocks following the restoration of degraded landscapes. We harvested and weighed 84 trees from eleven dominant species from six grazing exclosures and adjacent communal grazing land. We observed that AGB correlates significantly with diameter at stump height D-30 (R-2 = 0.78; P<0.01), and tree height H (R-2 = 0.41, P<0.05). Our best model, which includes D-30 and H as predictors explained 82% of the variations in AGB. This model produced the lowest bias with narrow ranges of errors across different diameter classes. Estimated C-stock showed a significant positive correlation with stem density (R-2 = 0.80, P<0.01) and basal area (R-2 = 0.84, P<0.01). At the watershed level, the mean C-stock was 3.8 (+/- 0.5) MgCha(-1). Plot-level C-stocks varied between 0.1 and 13.7MgCha(-1). Estimated C-stocks in three-and seven-year-old exclosures exceeded estimated C-stock in the communal grazing land by 50%. The species that contribute most to C-stocks were Leucaena sp. (28%), Calpurnia aurea (21%), Euclea racemosa (20.9%), and Dodonaea angustifolia (15.8%). The equations developed in this study allow monitoring changes in C-stocks and C-sequestration following the implementation of restoration practices in northern Ethiopia over space and time. The estimated C-stocks can be used as a reference against which future changes in C-stocks can be compared.

Authors with CRIS profile

Mulugeta Mokria Lehrstuhl für Geographie (Physische Geographie) Achim Bräuning Lehrstuhl für Geographie (Physische Geographie)

Involved external institutions

International Crops Research Institute for the Semi-Arid Tropics ICRISAT IN India (IN) Amhara Regional Agricultural Research Institute (ARARI) ET Ethiopia (ET) World Agroforestry Centre KE Kenya (KE) International Water Management Institute (IWMI) LK Sri Lanka (LK)

How to cite

APA:

Mokria, M., Mekuria, W., Gebrekirstos, A., Aynekulu, E., Belay, B., Gashaw, T., & Bräuning, A. (2018). Mixed-species allometric equations and estimation of aboveground biomass and carbon stocks in restoring degraded landscape in northern Ethiopia. Environmental Research Letters, 13(2). https://dx.doi.org/10.1088/1748-9326/aaa495

MLA:

Mokria, Mulugeta, et al. "Mixed-species allometric equations and estimation of aboveground biomass and carbon stocks in restoring degraded landscape in northern Ethiopia." Environmental Research Letters 13.2 (2018).

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