Deforestation and fragmentation trends of seasonal dry tropical forest in Ecuador: impact on conservation

Abstract

Background Fragmentation and deforestation are one of the greatest threats to forests, and these processes are of even more concern in the tropics, where the seasonal dry forest is possibly one of the most threatened ecosystems with the least remaining surface area. Methods The deforestation and fragmentation patterns that had occurred in Ecuadorian seasonal dry forests between 1990 and 2018 were verified, while geographic information systems and land cover shapes provided by the Ecuadorian Ministry of the Environment were employed to classify and evaluate three types of seasonal dry forests: deciduous, semi-deciduous, and transition. The study area was tessellated into 10 km2 hexagons, in which six fragmentation parameters were measured: number of patches, mean patch size, median patch size, total edge, edge density and reticular fragmentation index (RFI). The RFI was also measured both outside and inside protected natural areas (unprotected, national protected areas and protected forest). Moreover, the areas with the best and worst conservation status, connectivity and risk of disappearance values were identified by means of a Getis-Ord Gi* statistical analysis. Results The deforestation of seasonal dry forests affected 27.04% of the original surface area still remaining in 1990, with an annual deforestation rate of − 1.12% between 1990 and 2018. The RFI has increased by 11.61% as a result of the fact that small fragments of forest have tended to disappear, while the large fragments have been fragmented into smaller ones. The semi-deciduous forest had the highest levels of fragmentation in 2018. The three categories of protection had significantly different levels of fragmentation, with lower RFI values in national protected areas and greater values in protected forests. Conclusions The seasonal dry forest is fragmenting, deforesting and disappearing in some areas. An increased protection and conservation of the Ecuadorian seasonal dry forest is, therefore, necessary owing to the fact that not all protection measures have been effective.

The expansion of olive groves is reducing habitat suitability for the Great Bustard Otis tarda and the Little Bustard Tetrax tetrax in Southern Spain: could Important Bird Areas (IBAs) reduce this expansion?

“…The fragmentation of arable land (the most important land use in Andalusia for steppe birds) in each of the UTM cells, into which the distribution of the Great Bustard and the Little Bustard were divided, was calculated using the Reticular Fragmentation Index (RFI) proposed by Leautaud Valenzuela (2014) (Formula 1): where ED is the Edge Density, calculated as the amount of edge (km) relative to the land-use area (km 2 ) within the UTM cell, and AWH is the percentage of area without arable land within the UTM cell (Rivas et al . 2021). In order to determine 100% of the AWH% and ED% metrics, a 500 x 500 m plot of a certain land in 1990 was used as a reference value.…”

“…where ED is the Edge Density, calculated as the amount of edge (km) relative to the land-use area (km 2 ) within the UTM cell, and AWH is the percentage of area without arable land within the UTM cell (Rivas et al 2021). In order to determine 100% of the AWH% and ED% metrics, a 500 x 500 m plot of a certain land in 1990 was used as a reference value.…”

Changes in seed hydration memory expression through different seasons in a Seasonally Dry Tropical Forest

“…The differentiated germinal response between seeds produced in the dry and rainy seasons may also be related to epigenetic changes induced by abiotic stress which, according to Chinnusamy and Zhu (2009), have adaptive advantages for conservation of species in situ. It is worth noting that Seasonally Dry Tropical Forests are among the most threatened ecosystems and can become increasingly arid areas due to increasing droughts and global temperatures (Baccini et al 2017;Rivas et al 2021). In future climate scenarios, with reduced rainfall, strategies that allow the population dynamics of species in these ecosystems may become ine cient to overcome such drought conditions and, consequently, limit germination, as pointed out by Dantas et al (2018).…”

The limits to growth of buen vivir socialism: Ecuador's alternative development model from 2007 to 2017

“…Toda la política económica ecuatoriana favoreció y está favoreciendo ese proceso. La deforestación se ha visto fortalecida debido a la implantación de distintos planes de desarrollo que fomentan el extractivismo, la extracción de recursos naturales a gran escala, el crecimiento de las fronteras agrícolas, la dependencia económica de las actividades forestales y agrícolas de amplias regiones del país (especialmente las regiones tropicales), la dependencia económica generalizada de los sectores más pobres de la población de las actividades forestales y agrícolas para subsistir, el uso de la leña como combustible más habitual entre los hogares con menores ingresos, la escasez de programas de reforestación y conservación de la naturaleza, y el aumento de la población, entre otros factores (Fischer et al 2021;Heredia-R et al 2021;Ojeda Luna et al 2020;Rivas et al 2021;Vallejo & Caicedo 2020;Viteri-Salazar & Toledo 2020).…”