Multitemporal analysis of forest fragmentation in Hindu Kush Himalaya—a case study from Khangchendzonga Biosphere Reserve, Sikkim, India

Abstract

Forests in the mountains are a treasure trove; harbour a large biodiversity; and provide fodder, firewood, timber and non-timber forest products; all of these are essential for human survival in the highest mountains on earth. The present paper attempts a spatiotemporal assessment of forest fragmentation and changes in land use land cover (LULC) pattern using multitemporal satellite data over a time span of around a decade (2000-2009), within the third highest protected area (PA) in the world. The fragmentation analysis using Landscape Fragmentation Tool (LFT) depicts a decrease in large core, edge and patches areas by 5.93, 3.64 and 0.66 %, respectively, while an increase in non-forest and perforated areas by 6.59 and 4.01 %, respectively. The land cover dynamics shows a decrease in open forest, alpine scrub, alpine meadows, snow and hill shadow areas by 2.81, 0.39, 8.18, 3.46 and 0.60 %, respectively, and there is an increase in dense forest and glacier area by 4.79 and 10.65 %, respectively. The change analysis shows a major transformation in areas from open forest to dense forest and from alpine meadows to alpine scrub. In order to quantify changes induced by forest fragmentation and to characterize composition and configuration of LULC mosaics, fragmentation indices were computed using Fragstats at class level, showing the signs of accelerated fragmentation. The outcome of the analysis revealed the effectiveness of geospatial tools coupled with landscape ecology in characterization and quantification of forest fragmentation and land cover changes. The present study provides a baseline database for sustainable conservation planning that will benefit the subsistence livelihoods in the region. Recommendations made based on the present analysis will help to recover forest and halt the pessimistic effects of fragmentation and land cover changes on biodiversity and ecosystem services in the region.

Assessment of Land-Use/Land-Cover Change and Forest Fragmentation in the Garhwal Himalayan Region of India

“…The forest was the main land cover in the study area. The overall trend shows that the forest area had decreased and the non-forest area had increased in the Rudraprayag district; the overall loss of the forest was 122.35 km 2 from 1976 to 2014.This result agrees with other studies conducted in the Himalayan region of India [51,52]. The general trends of change showed an increase in agriculture, barren land, built-up area, and scrub land.…”

“…The local community depends highly on agricultural activity, which would be further expected with a decline in forest cover. Other studies also found similar causes of forest decline in the Hindu Kush Himalaya (HKH) region [49,[52][53][54]. Although natural drivers could also play a role in land cover change, the scope of this study mainly focused on anthropogenic activities.…”

Analysis of Long-Term Spatio-Temporal Trends in Land Use/Land Cover in Devikulam Taluk, Kerala Using Geospatial Techniques

“…Accuracy Assessment of a classified product is a must and is used as a certification for further use in any information interpretation and further modelling. Accuracy of a classified image is generally determined by comparing certain pixels (a sample) of the classified map with the reference (for which the class is known) pixels (Sharma et al, 2016). The source of reference pixels in this study were the GCPs (Ground Control Points) collected during fieldwork and randomly generated sample points in ERDAS Imagine software.…”

Análisis del proceso de fragmentación de bosques: metodologías orientadas en el uso de sistemas de información geográfica y métricas del paisaje

“…Es un proceso dinámico (6) en el que un área amplia e intacta de bosque es progresivamente subdividida en pequeños parches o fragmentos (8,10) geométricamente alterados y aislados (2,5,6,11) inscritos en otros usos del suelo distintos (12), rodeado por matrices generalmente antrópicas (13), lo que genera la modificación de las condiciones medioambientales y el funcionamiento de los ecosistemas (14), (15), provocando elevada mortalidad de árboles y plantas juveniles (13), caída acelerada de las hojas, alteración en el almacenamiento de carbono, y en otros procesos como la abundancia de algunas especies, en la productiva, formación de detritus, movimiento de agua y nutrientes, la sucesión y la competencias entre otros (16,17). Autores han descrito el proceso de fragmentación en cuatro etapas: i) la perforación, en la cual se crea un agujero o hueco en la cobertura original; ii) la subdivisión, en la cual las áreas de coberturas de la tierra más grandes se dividen en parches más pequeños; iii) la contracción, que es la etapa en la cual se pierde la conectividad entre los parches de cobertura original; y por último, iv) la etapa de desgaste, en la cual los parches originales del paisaje disminuyen gradualmente en tamaño hasta que finalmente desaparecen (18,19).…”

“…Debido a esto, ha emergido como una prioridad de investigación, la comprensión de la dinámica de la fragmentación de bosques y los cambios en las coberturas de la tierra, para entender el desarrollo del pasado como base para la planeación y como guía para la conservación en un futuro (6,30). Esto ha ocasionado que el enfoque en la fragmentación tenga altas prioridades en la agenda local de los gobiernos para la formulación de políticas de protección y planeación de uso del territorio (2) de manera que las políticas dirigidas de modo adecuado pueden transformar las áreas agrícolas a bosques en áreas que formen corredores para la vida silvestres, garantizando la persistencia de especies y evitando que afecte negativamente la biodiversidad (31) (32) .…”