A global overview of the conservation status of tropical dry forests

Abstract

Aim To analyse the conservation status of tropical dry forests at the global scale, by combining a newly developed global distribution map with spatial data describing different threats, and to identify the relative exposure of different forest areas to such threats.Location Global assessment.Methods We present a new global distribution map of tropical dry forest derived from the recently developed MODIS Vegetation Continuous Fields (VCF) product, which depicts percentage tree cover at a resolution of 500 m, combined with previously defined maps of biomes. This distribution map was overlaid with spatial data to estimate the exposure of tropical dry forests to a number of different threats: climate change, habitat fragmentation, fire, human population density and conversion to cropland. The extent of tropical dry forest currently protected was estimated by overlaying the forest map with a global data set of the distribution of protected areas.

Fire, climate and vegetation linkages in the Bolivian Chiquitano seasonally dry tropical forest

“…Our study area is the Bolivian Chiquitano SDTF-the largest intact, old-growth block of SDTF in South America [1]. This semi-deciduous to deciduous forest covers most of the calcareous rolling hills of eastern Bolivia (Chiquitanía), interspersed with patches of cerrado savanna where soils are either too nutrient-poor or too thin to support forest [8].…”

Tropical dry forests: The state of global knowledge and recommendations for future research

“…As a result, the Caatinga may be excluded from relevant research and reporting (such as forest clearance figures); this issue (also present for some of the African miombo and Brazilian cerrado (Miles et al 2006)) highlights the need for an accepted, standardized definition of dry forests.…”

“…However, some research on defining the extent of such forests is available (see FAO 2001;Miles et al 2006;FAO 2012 According to Miles et al (2006), less than one-third of the world's dry forest area lies within protected areas. Despite general agreement in the literature that dry forests are under threat (see Kowero 2003;Gillespie et al 2012), comprehensive data on the rates of deforestation and conversion of dry forests are difficult to find.…”

“…The first of these could be from Latin America, as dry forests on that continent are considered among the most at risk (Miles et al 2006). …”

“…Despite their importance, dry forests are among the most threatened and least studied of the world's forested ecosystems and, as a result, may be at greater risk than humid forests (Janzen 1988;Miles et al 2006; Portillo-Quintero and Sánchez-Azofeifa 2010; Aide et al 2012;Gillespie et al 2012). For example, the dry forests of some Pacific islands are thought to have been reduced to less than 10% of their original extent, with the remainder still threatened by human activity and the invasion of exotic species (Gillespie et al 2012).…”