Bits and pieces: Forest fragmentation by linear intrusions in India. (December 2020)

• Record Type: Journal Article
• Authors: Nayak, Rajat; Karanth, Krithi K.; Dutta, Trishna; Defries, Ruth; Karanth, K. Ullas; Vaidyanathan, Srinivas
• Is Part Of: Land use policy. Volume 99(2020)
• Publication Date: 2020-12
• Subjects: AP amount of perforation -- ENVIS environmental information system -- FC fragmentation category -- India-WRIS water resources information system of India -- IPD inter-patch distance -- LULC land use/land cover -- MoEFCC Ministry of Environment Forest and Climate Change -- NRSA National Remote Sensing Agency -- PA protected area -- PS patch size; Infrastructure -- Patch indices -- Patch size -- Inter-patch distance -- Western Ghats -- Central India; Land use -- Periodicals; Land use -- Government policy -- Periodicals; Sol, Utilisation du -- Périodiques; Sol, Utilisation du -- Politique gouvernementale -- Périodiques; Electronic journals; 333.7305
• DOI: 10.1016/j.landusepol.2020.104619
• Languages: English
• ISSNs: 0264-8377

Abstract

Highlights: There was a 6% increase in number of patches due to linear infrastructure. 60 % of India's forest cover is represented by < 1% of the forest patches. 70 % of the assessed PAs had linear infrastructure passing through them. Central India has more number of large patches (> 1000 km 2 ) than the Western Ghats. Patches in Central India are more isolated than patches in the Western Ghats. Abstract: Linear infrastructure development is an important driver of forest fragmentation leading to habitat and biodiversity loss as well as disruption of critical ecosystem processes. The tropical forests of India are increasingly impacted by infrastructure development. Little quantitative information is available on the extent of fragmentation due to linear infrastructure on these habitats. Here, we quantified fragmentation due to linear infrastructure by studying forest structural connectivity. We compared the existing forest patch characteristics with a scenario that excluded all linear infrastructure. We classified forest patches into three different fragmentation categories that combined information on patch size, inter patch distance and percentage perforations. Results show that power-transmission lines and roads were the most common infrastructure features within forests. We found a 6% increase in the number of forest patches due to the construction of linear infrastructure. Forest patches >10, 000 km 2 in size were severely affected and there was a 71.5 % reduction in the number of such patches. We found that 86 % of the existing forest patches are in the small (median patch size <1 km 2 ) and isolated (a median distance of 155 m) category. The density of linear infrastructure inside protected areas was similar to density in non-protected forested areas. Our results highlight the need to minimize the effects of fragmentation in the future by considering re-routing or bundling of infrastructure. When infrastructure is unavoidable, there is a need to mitigate their potential impacts. The results of this study have been made publicly accessible (https://indiaunderconstruction.com ) to provide information on 'where' to avoid future linear infrastructure development and to make informed decisions which can lead to optimally designed local management plans.