Examining Patterns and Impacts of Forest Resource Extraction and Forest Degradation in Tropical Dry Forests

Introduction

Tropical dry forests have historically had a high rate of resource exploitation across the world (Janzen, 1988; Miles et al., 2006). Presently, only 17% of the tropical forests that remain across the world are dry forests as the rate of clearing tropical dry forests and forest degradation continue to remain high and present unique challenges to forest conservation (Miles et al., 2006). Of this 17% that remain, 54% of the dry forests are found in the Americas (Miles et al., 2006). This rate of exploitation is primarily due to the affinity humans have for these forests. Dry forests are mainly located in relatively flat terrains, which receive seasonal rainfall(Fajardo et al., 2005). Further, a lower biomass and structural complexity in comparison to tropical humid forests makes them ideal for clearing by humans to engage in short-cycle crop agriculture, livestock farming (Fajardo et al., 2005). Humans have relied on tropical dry forests for several resources including biomass for construction and fuel, fruits and edible flowers, leaves and medicinal plants and continue to do so even today (Castillo et al. 2005; Portillo-Quintero et al. 2014; Portillo-Quintero & Smith, 2018).

Due to the historic exploitation of these forests and rapid human population growth, large contiguous areas of tropical dry forests presently only remain in Brazil, Bolivia and Paraguay in South America (Gillespie et al., 2012). While tropical dry forests thrive in some parts of the world, they are among the least protected and possibly the most vulnerable to anthropogenic disturbances in the world (Gillespie et al., 2012). Deforestation for agricultural purposes has been the largest threat to tropical dry forests, however, forest degradation is also a cause for concern; however, forest degradation, which is more cryptic is also a major threat to this forest type (Gillespie et al., 2012; Puyravaud, Davidar, & Laurance, 2010; Thompson et al., 2013). Numerous reports have attempted to estimate the extent of global forest degradation across the world, with one estimate by the International Tropical Timber Organization (ITTO; ITTO, 2002) at 850 million hectares across the tropics.

The high human dependence on tropical dry forests underscores the need for a complete understanding of the interaction of humans and these forests to ensure their persistence. In the recent past, ecosystem conservation has taken the form of ‘fortress conservation’ (Chan et al., 2007). However, humans have relied on tropical dry forests for centuries, making forests an integral part of their lifestyle and livelihoods and a model of fortress conservation may not provide the intended impact (Kareiva et al., 2007). In order to successfully conserve and manage tropical dry forests, it is critical to understand the impacts of human resource use and what constitutes forest degradation. Further, using this knowledge of the impacts of forest resource use, natural resource managers and scientists may create a model of forest conservation and management that fulfils the needs of people who rely on forests and the environmental conservation agenda.