Deforestation pattern dynamics in protected areas of the Brazilian Legal Amazon using remote sensing data

Abstract

Forest fragmentation and deforestation are subjects of great concern in tropical regions, namely in South America and Africa, contributing to a rapid loss of tropical forest area and with serious implications for ecosystem functioning and biodiversity conservation. Despite the decrease in deforestation rates in recent years, the Brazilian Amazon, with the largest continuous region of tropical forest in the world, has suffered the greatest recorded losses, which have been contributing to continuous habitat fragmentation and a reduction in the territory occupied by Amerindian populations. In an attempt to preserve the remaining habitats and forests, Brazil has been adopting land conservation policies, including the implementation of protected areas. Protected areas (PAs) possess the potential to significantly reduce habitat fragmentation by conserving large, contiguous areas of land. In order to examine how effective PAs are at conserving forest area in the Brazilian Legal Amazon, patterns of deforestation are analyzed and compared, inside and outside the PAs, through landscape metrics calculated using the Patch Analyst and V-LATE extensions of a Geographic Information System. Two different sources (the Hansen Global Forest Change Dataset and the Brazilian National Institute for Space Research's (INPE) PRODES project) of annual forest cover-loss data derived from satellite imagery at medium-to-high spatial and temporal resolutions are compared at two-yearly intervals across 2002-2016. Additionally, fragmentation levels associated with deforestation patterns are assessed through an index modeled using a set of uncorrelated landscape metrics, and the associated change factors and trend are discussed. Results show that there is greater fragmentation in some PAs located in Mato Grosso and Pará States, especially those near the "arc of deforestation", and that Yanomami Indigenous Lands (YIL) are tending towards more fragmentation. Although some PAs are in a critical condition, findings show they all actively contribute to improved conservation of the native ecosystem and, in conjunction with sustainable management policies, will continue to help reduce or avoid forest fragmentation and degradation processes.

Increasing fragmentation of forest cover in Brazil’s Legal Amazon from 2001 to 2017

“…The forest cover fragmentation within conservation units and indigenous reserves was less intense than outside of these areas, with integral protection conservation units showing the lowest rate of fragmentation. This result agrees with the findings of Cabral et al 32 , who stated that these areas actively contribute to improved conservation and to reducing or preventing forest fragmentation and degradation processes in the BLA. Outside of conservation units and indigenous reserves, the fragmentation increased and remained high even in years with decreased forest loss (e.g., 2011).…”

“…However, the smaller mean size of forest loss patches observed in these areas presents another challenge for the monitoring systems and conservation efforts. As Cabral et al 32 also noted, our results suggest that most of the forest loss occurred in areas with a low level of protection, such as environmental protection areas. It is important to note that we did not evaluate whether the protection level provided in different types of conservation unit affected the forest loss process.…”

“…We used the delimitation of indigenous reserves and conservation units provided by the Environmental Ministry of Brazil to define pixels that belonged to these areas (http://mapas.mma.gov.br/i3geo/datadownload.htm). Using these limits, we were able to analyze forest fragmentation and forest loss separately in conservation units of integral protection areas, which have strict rules for forest conservation, and in conservation units defined as sustainable units, which allow sustainable uses of the forest 32 . Due to overlaps among the conservations units and indigenous reserves, we divided our analysis into four categories: (i) conservation units based on integral protection, (ii) conservation units based on sustainable use, (iii) indigenous reserves and (iv) regions with overlapping categories.…”

“…The objectives of our work were to evaluate the spatio-temporal pattern of forest loss and forest cover fragmentation from 2001 to 2017. We separately examined areas within and outside of indigenous reserves and conservation units where the forest is either managed under more strict regulations (i.e., sustainable use) or where forest is completely protected (i.e., integral protection conservation units and indigenous reserves) 32 , and separately examined primary and non-primary forest. We used spatial landscape metrics and hotspot analysis to capture the spatial and temporal patterns of change in forest loss and forest cover throughout the BLA by focusing on whether the processes differ between the primary and non-primary forest types and between the areas inside and outside of the indigenous reserves and conservation areas.…”

Dynamics of land use and land cover in the agricultural frontier of the Brazilian Amazon: driving forces of changes and future scenarios

“…Both GFC and CLASlite have been employed to map deforestation and general disturbance (deforestation and degradation considered together) in tropical regions such as Indonesia (Arjasakusuma et al, 2018), Africa (Dlamini, 2017;Lui and Coomes, 2015), and, in conjunction with PRODES/INPE in the Amazonia (Cabral et al, 2018;Hansen et al, 2008;Milodowski et al, 2017). These studies indicate that GFC can overestimate (Arjasakusuma et al, 2018) or underestimate (Dlamini, 2017;Milodowski et al, 2017) deforestation detection (Tropek et al, 2014).…”