JoRSG (2015) 1-10 © STM Journals 2015. All Rights Reserved Page 1 Journal of Remote Sensing & GIS ISSN: 2230-7990(online), ISSN: 2321-421X(print) Volume 6, Issue 1 www.stmjournals.com Landscape Characterization in a Watershed of Western Himalayan Ecoregion N.K. Sharma* Scientist, Jharkhand Space Applications Center, Ranchi, Jharkhand, India Abstract The study was carried out in Kalsa watershed of Western Himalayan Ecoregion to quantify the landscape structure with special reference to different forest ecosystems. Vegetation and land use map generated using satellite remote sensing data was taken as an input for quantification of landscape structure, which was quantified based on different patch attributes (number, area, shape complexity) and landscape indices viz., Euclidean nearest neighbor distance and contagion. Temperate broadleaf forest exhibited high values for mean patch area, largest patch area, contagion and low values for number of patches, shape complexity and Euclidian nearest neighborhood in contrast to the degraded forest. Keywords: Landscape indices, vegetation map, patch analysis, contagion, ENN *Author for Correspondence E-mail: sharmank@rediffmail.com INTRODUCTION Traditional ecology focuses on the vertical aspect only which studies the relationship of organisms and their environment in the homogeneous spatial unit, while landscape ecology focuses on the horizontal aspect that is the relationship between the spatial units in addition to the vertical approach [1]. Quantification of landscape patterns has become the prerequisite to study the relationship of ecological processes with landscape patterns [2–6]. Pattern maps are useful because they quantify biologically relevant information that is not evident from a land cover map [7]. To quantify landscape pattern many landscape indices have been formulated [3, 4, 6, 8–12]. A robust landscape index quantifies land use categories or “patch” types and their relative proportions in the landscape and spatial pattern of patches in the landscape [10]. A patch may be defined as a nonlinear surface area differing in its appearance from surrounding area varying in size, shape, type, heterogeneity, and boundary characteristics normally represented by plant and animal communities in a landscape [8]. In India the landscape level studies were initiated by Roy and Tomar [13] which later on materialized in the form of national level study covering all the forest ecosystems of India [14–18]. Ritters et al. [19] on the basis of analysis of 55 landscape metrics using multivariate factor analysis for statistical independence concluded that many of the metrics have been found highly correlated with each other the information contained in 55 metrics could be explained by six metrics viz., average perimeter area ratio, contagion, standardized patch shape, patch perimeter area scaling, number of attribute classes, and large patch density area scaling. Environment Protection Agency (EPA) ranked the landscape metrics in three categories viz., A (requiring further conceptual development), B (requiring testing for feasibility/sensitivity) and C (ready for field tests and implementation) [20]. Different indices classified in C category are contagion, fractal dimension, dominance, change of habitat, loss of rare land cover, amount of edges and patch size distribution. In present study landscape was characterized using Number of Patches, Mean Patch Area, Largest Patch Area and Perimeter-Area Fractal dimension indices at class level and Eucledian Nearest Neighbor and Contagion index at landscape level. The aim of the study was to investigate the landscape composition, structure and patch level characterization of different forest types.