Paudel Gayatri, Pandey Kabita, Lamsal Puspa, Bhattarai Anita, Bhattarai Aayush, Tripathi Shankar
Institute of Forestry, Tribhuvan University (TU), Nepal.
Faculty of Forestry, Agriculture and Forestry University (AFU), Nepal.
Heliyon. 2024 May 18;10(11):e31305. doi: 10.1016/j.heliyon.2024.e31305. eCollection 2024 Jun 15.
Forest fires are an imminent danger to natural forest ecosystems, and carrying out zoning studies and forest fire risk assessments are of great practical significance in steering fire prevention, minimizing fire incidents, and limiting the environmental consequences of fire. Using the Gorkha district of Nepal as a case study, this study used remotely sensed high-temperature fire data as the forest fire sample. Nine parameters related to topography, climatic conditions, vegetation, and human intervention were used as environmental variables affecting fire occurrence. Next, a MaxEnt forest fire risk assessment model was generated with GIS and R, which analysed the contribution, significance, and responses of environmental variables to the forest fire in Gorkha District. The findings demonstrate that (1) following a test of sample locations for forest fires, the MaxEnt model has excellent relevance and practicality when applied to fire risk assessment; (2) Out of 2747 fire points in the forest, only 110 Spatio-temporally independent fire points were used for the model building having high and normal confidence level. Regarding Area Under Curve (AUC) values, the training data yielded results of 0.875, while the test data produced acceptable results of 0.861 with a standard deviation of 0.0322; (3) the importance of climatic and Land Use Land Cover (LULC) variables to forest fire are 56.2 % and 32.9 %, respectively, and their contribution to forest fire are 32 % and 47.6 %, respectively. (4) There are numerous and intricate ways that environmental factors influence forest fires. The forest fire response curves to the nine chosen environmental variables are complex and nonlinear rather than linear; Maximum temperature of the warmest month (bio_5), Isothermality (bio_3), Precipitation of Driest Quarter (bio_17) and mean Diurnal Range (bio_2) bear a nonlinear positive link with the possibility of forest fires. In contrast, elevation, slope, temperature seasonality (bio_4), distance from the settlement, and LULC have a favorable stimulating response to the possibility of forest fires within an appropriate interval. (5) In Gorkha, there are geographical differences in the risk of forest fires. Only 12.83 % of the whole area is made up of areas at significantly high risk or above, compared to 87.17 % for high-risk and below.
森林火灾对天然森林生态系统构成了紧迫威胁,开展分区研究和森林火灾风险评估对于指导火灾预防、减少火灾事故以及限制火灾对环境的影响具有重大现实意义。本研究以尼泊尔戈尔哈地区为例,将遥感高温火灾数据作为森林火灾样本。选取了与地形、气候条件、植被和人类干预相关的9个参数作为影响火灾发生的环境变量。接下来,利用地理信息系统(GIS)和R软件生成了MaxEnt森林火灾风险评估模型,分析了环境变量对戈尔哈地区森林火灾的贡献、显著性及响应情况。研究结果表明:(1)在对森林火灾样本位置进行检验后,MaxEnt模型应用于火灾风险评估时具有良好的相关性和实用性;(2)在森林中的2747个火点中,仅110个时空独立的高置信度和正常置信度火点用于模型构建。就曲线下面积(AUC)值而言,训练数据结果为0.875,测试数据产生了可接受的结果0.861,标准差为0.0322;(3)气候和土地利用土地覆盖(LULC)变量对森林火灾的重要性分别为56.2%和32.9%,它们对森林火灾的贡献分别为32%和47.6%;(4)环境因素影响森林火灾的方式众多且复杂。森林火灾对所选9个环境变量的响应曲线复杂且非线性而非线性;最暖月最高温度(bio_5)、等温性(bio_3)、最干季度降水量(bio_17)和平均日较差(bio_2)与森林火灾发生可能性呈非线性正相关。相比之下,海拔、坡度、温度季节性(bio_4)、距定居点距离和LULC在适当区间内对森林火灾发生可能性具有有利的促进响应;(5)在戈尔哈,森林火灾风险存在地理差异。整个区域中,极高风险及以上区域仅占12.83%,高风险及以下区域占87.17%。