Characterizing changes in land cover and forest fragmentation in Dhorpatan Hunting Reserve of Nepal from multi-temporal Landsat observations (1993-2018)

Abstract

14 ABSTRACT15 Recent centuries have experienced drastic changes in land cover around the world where 16 Himalayan countries like Nepal have undergone changes in the past several decades because of 17 increasing anthropogenic pressure, natural risks and climatic factors. Accordingly, forest 2 18 fragmentation has also been increasing alarmingly, which is a matter of concern for natural 19 resource management agencies and biodiversity conservation communities. In this study, we 20 assessed land cover change and forest fragmentation trends in Dhorpatan Hunting Reserve of 21 Nepal by implementing landscape fragmentation and recovery process models, and calculating 22 landscape indices based on five-date land cover maps derived from Landsat satellite images from 23 1993 to 2018. Six land cover types including forest, grass land, barren land, agriculture & built-24 up, water bodies and snow & glaciers were determined after an intensive field survey. Diverse 25 derived image features were fed to the Support Vector Machines classifier to create land cover 26 maps, followed by a validation procedure using field samples and reference data. Land cover maps 27 showed an increase in forest area from 37.32% (1993) to 39.26% (2018) and snow & glaciers from 28 1.72% (1993) to 2.15% (2018) while a decrease in grassland area from 38.78% (1993) to 36.41% 29 (2018) and agriculture & built-up area from 2.39% (1993) to 1.80% (2018). Barren land and water 30 body showed negligible changes. The spatial explicit process of forest fragmentation indicated that 31 shrinkage was the most responsible factor of forest loss while expansion was dominant to 32 increment for forest restoration. High dependency of people persists on the reserve for subsistence 33 resources being a cause of forest fragmentation and posing threats to biodiversity. Focus should 34 be made on strategies to decrease the anthropogenic pressure on the reserve. This requires 35 approaches that provide sustainable alternative resources to the local people and innovations that 36 will help them become less reliant on natural resources. 37 39 3 40 Introduction 41 Land use land cover (LULC) change is considered as one of the most important variables of global 42 ecological change since its impacts are profound and range from global carbon and hydrologic 43 cycle to aerosols and local biodiversity [1]. Land use refers to human activity on a piece of land 44 for different purposes such as industrial zones, residential zones, and land cover refers to its 45 surface features such as forest, grassland, etc [2, 3]. Land use is one of the main factors through 46 which humans influence the environment. It involves both the manner in which the biophysical 47 attributes of the land are manipulated and the intent underlying that manipulation [4]. There's a 48 direct link between land cover and the actions of people in their environment, i.e., land use may 49 lead to land cover change. 50 There have been drastic changes in LULC over recent centuries where Nepal has undergone 51 constant c...

Effects of hydroelectric dam construction on spatio-temporal changes of land use land cover in Bui National Park, Ghana

“…Many small villages are scattered inside the reserve, and several others exist along the fringes. The huge number of people present in and outside the BNP carrying out several activities (Appiah et al, 2017) is linked to exploitation of forest resources on a daily basis (Sharma et al, 2019). These anthropogenic activities are escalating, affecting the reserve resources due to the continuous illegal entry of people into the reserve.…”

“…The grassland decreased its cover from 2010-2020. Other researches (Chalise et al, 2019;Özüpekçe, 2019;Wiejaczka et al, 2017;Xu & Chi, 2019) This causes reduction in quality and quantity of forage as well as modifying vegetation and soil formation due to soil compaction (Obahoundje et al, 2018;Panthi et al, 2017;Sharma et al, 2019). In some cases, cattle herdsmen attempt to cause regeneration of fresh pasture by consciously setting fire to the vegetation resulting in uncontrolled destruction of vegetation (Sharma et al, 2019).…”

Spatio-Temporal Analysis of Forest Fragmentation in Río Botello Catchment at Facatativá (Colombia)

“…Most studies limit their scope to identifying a landscape fragmentation pattern by a time window of interest. However, the fragmentation process of the landscape is more appropriately measured by changes in the landscape metrics at two or more points in time [18][19][20][21][22][23]. Therefore, in order to contribute to land planning and development of conservation programs in rural areas, the spatial and temporal analyzes of fragmentation dynamics at catchment scale become study strategies that are applicable to different scenarios.…”