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Forest fires are a recurrent management problem in the Western Ghats of India. Although most fires occur during the dry season, information on the spatial distribution of fires is needed to improve fire prevention. We used the MODIS Hotspots database and Maxent algorithm to provide a quantitative understanding of the environmental controls regulating the spatial distribution of forest fires over the period 2003–07 in the entire Western Ghats and in two nested subregions with contrasting characteristics. We used hierarchical partitioning to assess the independent contributions of climate, topography and vegetation to the goodness-of-fit of models and to build the most parsimonious fire susceptibility model in each study area. Results show that although areas predicted as highly prone to forest fires were mainly localised on the eastern slopes of the Ghats, spatial predictions and model accuracies differed significantly between study areas. We suggest accordingly a two-step approach to identify: first, large fire-prone areas by paying special attention to the climatic conditions of the monsoon season before the fire season, which determine the fuels moisture content during the fire season; second, the most vulnerable sites within the fire-prone areas using local models mainly based on the type of vegetation.

We describe the mesoscale floristic patterns in the central Western Ghats of Karnataka, India, through combined analysis of woody species abundance and stand structure data from a network of ninety‐six 1‐ha sampling plots spread across 22,000 km2. A total of 61,906 individuals (≥10 cm gbh) comprising 400 plant species from 254 genera and 75 families were recorded. Euphorbiaceae, Rubiaceae, Lauraceae and Moraceae families constituted 23.5 percent of the total number of species encountered. The relative dominance of species was skewed with Poecilonueron indicum, Xylia xylocarpa, Terminalia tomentosa and Anogeissus latifolia being dominant in some plots. Correspondence analysis (CA) and a nonmetric multidimensional scaling (NMDS) of plots by species abundances data showed similar arching patterns, with significant correlation between the first axis of CA and NMDS (r=0.77). Hierarchical clustering of plot scores along the three first CA axes resulted in splitting the plots into five different categories that broadly reflect the major bioclimatic features of the region. A multiscale bootstrapping test indicated that categorization of the wettest (wet evergreen group 1 and 2) and driest (dry deciduous) groups were robust (P<0.05 with 1000 bootstraps), while the remaining two transitional groups were uncertain (P=0.12 and 0.26 for moist deciduous and semi‐evergreen group, respectively). Principal component analysis revealed that plots with similar floristic composition can encompass contrastingly different physiognomic structures (canopy cover, canopy height and mean tree diameter) probably in relation to their levels of disturbance. Observed patterns in the floristic composition have been discussed in the light of the complex interaction between the bioclimatic and disturbance regimes that characterize the region.

This data set reports woody plant species abundances in a network of 96 sampling sites spread across 22 000 km2 in the central Western Ghats region, Karnataka, India (74°15′–75°40′ E; 15°15′–13°30′ N). Due to its varied climate and diverse topography, the study area, which is part of the Western Ghats–Sri Lanka biodiversity hotspot, supports a wide array of non‐equatorial tropical habitats including wet evergreen, moist and dry deciduous, and intact as well as degraded forests and scrublands. These formations, floristically moderately rich and diversified, are characterized by a lower rate of endemism than in the southern part of the Western Ghats. This data paper provides abundance and girth data for 76 813 trees and lianas of 446 species collected in 96 sampling sites during 1996–1997. A total of 61 965 individuals ≥10‐cm girth at breast height (gbh) were recorded in 96 1‐ha macroplots, while 14 848 individuals <10 cm gbh, but >1 m height, were sampled in three 0.1‐ha microplots located within each macroplot. Additional data regarding the stand structure (average canopy height, percent canopy cover, number of strata) and the level of degradation are available for the macroplots, along with environmental data derived from other sources and analyses, such as soil types, rainfall, length of the dry season, and altitude. These data have been used to produce ecological research papers, as well as to elaborate conservation value maps and recommendations toward sustainable management of the forests of the central Western Ghats region.

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