Noble Ciar D, Gilroy James J, Peres Carlos A
School of Environmental Sciences, University of East Anglia, Norwich Research Park, Norwich, Norfolk, NR4 7TJ, UK.
School of Environmental Sciences, University of East Anglia, Norwich Research Park, Norwich, Norfolk, NR4 7TJ, UK.
J Environ Manage. 2025 Feb;375:124312. doi: 10.1016/j.jenvman.2025.124312. Epub 2025 Jan 25.
Over recent decades, forest fire prevalence has increased throughout the tropics, necessitating improved understanding of the landscape-scale drivers of fire occurrence. Here, we use MapBiomas land-cover and fire scar data to evaluate relationships between forest fragmentation, land-use, and forest fire prevalence in a typically consolidated Amazonian agricultural frontier: Portal da Amazonia, Mato Grosso, Brazil. Using zero-/zero-one-inflated Beta regressions, we investigate effects of forest patch (area, shape, surrounding forest cover) and landscape-scale variables (forest edge length, land-cover composition) on forest fire occurrence and density between 1985 and 2021. We show that fire density was greatest in small, complex forest patches. Small patches (≤100 ha) were also the dominant contributors to annual, regional forest fire cover. At the landscape-scale (100 km), forest edge length and urban land cover were positively associated with forest fire occurrence and density. Furthermore, forest fires were most likely to occur in landscapes consisting of ∼45% pasture cover, while fire density increased roughly linearly with pasture cover. Cropland cover was negatively associated with forest fire occurrence and density. Our findings indicate clear links between forest fragmentation and increased forest fire prevalence. This is cause for global concern, given that fragmentation rates throughout Amazonia are increasing, and fires are eroding the Amazon's capacity to act as a carbon sink. Efforts to minimise further fragmentation within Amazonia would likely help reduce forest fire prevalence. Within already fragmented regions, the conversion of pasture into crops, alongside targeted efforts to suppress fires within small forest patches and urbanized areas, may also limit fire prevalence.
在最近几十年里，热带地区森林火灾的发生率不断上升，因此有必要更好地了解火灾发生的景观尺度驱动因素。在这里，我们使用MapBiomas土地覆盖和火灾疤痕数据，来评估巴西马托格罗索州亚马逊门户这一典型的综合亚马逊农业前沿地区森林破碎化、土地利用与森林火灾发生率之间的关系。我们使用零膨胀/零一膨胀贝塔回归，研究了1985年至2021年期间森林斑块（面积、形状、周边森林覆盖）和景观尺度变量（森林边缘长度、土地覆盖组成）对森林火灾发生和密度的影响。我们发现，火灾密度在小而复杂的森林斑块中最高。小斑块（≤100公顷）也是年度区域森林火灾覆盖的主要贡献者。在景观尺度（100公里）上，森林边缘长度和城市土地覆盖与森林火灾的发生和密度呈正相关。此外，森林火灾最有可能发生在牧场覆盖率约为45%的景观中，而火灾密度大致随牧场覆盖率呈线性增加。农田覆盖与森林火灾的发生和密度呈负相关。我们的研究结果表明森林破碎化与森林火灾发生率增加之间存在明显联系。鉴于整个亚马逊地区的破碎化率在上升，且火灾正在削弱亚马逊作为碳汇的能力，这引起了全球关注。尽量减少亚马逊地区进一步破碎化的努力可能有助于降低森林火灾发生率。在已经破碎化的地区，将牧场转变为农田，同时有针对性地努力在小森林斑块和城市化地区扑灭火灾，也可能限制火灾发生率。
