Abstract

In the tropics, livestock grazing usually occurs simultaneously with charcoal production, yet empirical understanding of the combined activities remains poor, especially as regards to their effects on hydrological functions. Given predicted growth in both charcoal and beef production in Sub-Sahara Africa, South East Asia, and Central and South America, understanding the potential effects of maintaining this dual production system on local and landscape level hydrological dynamics is paramount for ensuring long-term ecosystem sustainability. Based on a synthesis of existing literature, we propose a theoretical and conceptual framework for analyzing the interlinks between charcoal, livestock, and hydrological processes where they co-exist. In a silo approach, we analyze the isolated effects of charcoal production and livestock on hydrological processes before exploring their combined effects (systemic approach). Given the scarcity of studies that explicitly treat the influence of traditional small-scale charcoal production on hydrological processes, we base our findings on existing knowledge about deforestation, forest fire and grazing impacts on hydrology. We find that exclusion of the effects of companion activities and omission of information on the intensity of biomass harvesting (i.e., pruning branches, selective harvest, clear cutting, uprooting tree stumps) can lead to over-attributing changes in hydrological processes to charcoal, thus exaggerating the effects on vegetation which might lead to inappropriate interventions. We also find that, in the case of livestock keeping, impacts on hydrological processes are highly dependent on grazing intensity, with low intensity grazing possibly having negligible or even positive effects on forest regrowth and thereby restoration of hydrological processes. Thus, the charcoal-livestock-water nexus may have a wide range of outcomes for hydrological processes ranging from negligible to highly profound effects, depending on key decisions in management and practice. To test these finding, however, field studies are needed with an explicit focus on the combined effects of different biomass harvesting practices and grazing intensities on hydrological processes across different scales. Albeit conceptual at this stage, we believe that our approach is a necessary first step in the process of diagnosing potential shortcomings of past approaches for studying charcoal production systems and developing new understanding of this three-way nexus.

Highlights

  • One third (2.4 billion) of global population depends on traditional woodfuels for most of their cooking and heating requirements (FAO, 2017)

  • The step by step hypothetical exploration we have conducted in this review of how different hydrological processes would play out in charcoal-livestock systems provides a preliminary analysis of the nexus

  • Throughout our undertaking of this analysis we have mainly focused on local influences of charcoal production and livestock, trying to understand how processes occurring at the level of individual trees and surrounding soils scale up to affect sitelevel biophysicochemical interactions, and the implications of all this on catchment discharge

Read more

Summary

INTRODUCTION

One third (2.4 billion) of global population depends on traditional woodfuels (charcoal and firewood) for most of their cooking and heating requirements (FAO, 2017). As long as the biomass harvesting method ensures that the soil structure remains intact for the most part, the direct influence of biomass harvesting for charcoal on infiltration is expected to be negligible This example highlights the importance of studying the specific effects of different biomass harvesting procedures on hydrological processes. Soil compaction increases soil bulk density and decreases porosity which, in turn, decreases water infiltration rates and, subsequently, increases surface runoff (Rauzi and Hanson, 1966; Hanson et al, 1970; Gifford and Hawkins, 1978; Mwendera and Mohamed Saleem, 1997) These processes can affect site-level nutrient cycles, soil moisture patterns, erosion and sediment yields, downstream water quality, and on-site productivity (Gifford and Hawkins, 1978), for the most part, they have been assumed rather than measured directly. The compacted soils in harvested areas and kiln sites might make it difficult for seeds to establish (Pedraza and Williams-Linera, 2003) as soil erosion would have swept off the seedbank and the litter and the first horizon layers necessary for healthy seedling establishment and growth

DISCUSSION
Findings
CONCLUSIONS
Background

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.