Human-induced land use changes and consequent enhanced greenhouse gas (GHG) emissions have been considered to be the prime driving force in the global warming and changes in the climate. In this context, understanding the process of land use changes has been vital towards mitigating the impacts of climate changes.  Land  use/ Land cover (LULC)  dynamics  and  its  effects  on  ecological  and hydrological process and on human livelihood has constituted major concerns today,  evident from the consideration of LULC change as an important climate forcing driver (NRC, 2005). Land management strategies involving the conversion of natural forests for agricultural and industrial activities (Hammett, 1992) are the causal factor for the changes in the land use.  LULC changes are local and place specific, collectively they are features of global environmental change. Land use  modification alter the structure of the landscape and hence the functional ability of the landscape.  Continual, historical, and precise information about the LULC changes of the Earth’s surface is essential for evolving appropriate management strategies towards the sustainable development of the landscape  (Abd El-Kawy et., al 2011). Environmental and ecological consequences of landscape transformation are more evident in natural ecosystems where their sustainability, multi-functional role and values are threatened (Narumalani et al., 2004; Schulz et al., 2010). Remote  Sensing and Geographic  Information  System are  main  platforms  of  data acquisition  and  analysis  of  LULC  changes  (Eastman  and Fulk,  1993;  Ehlers  et  al.,  1990;  Harris  and  Ventura,  1995; Dewan and Yamaguchi, 2009).  Multi-resolution (temporal, spatial and spectral) remote sensing data available since 1970’s aid in the analysis of long term  environmental  changes  and  impacts  of  human induced changes in the landscape (Xu  et  al.,  2005;  Berberoglu  and  Akin,  2009; Yu et al., 2011 ). Spatially explicit temporal data helps in the inventorying, mapping and monitoring spatio-temporal processes and changes. Understanding the causal factors with these changes is essential to develop mitigation and adaptation policies to minimize future disturbances while arresting further degradation (Marcucci, 2000).

Land use, Land cover and its change

Land cover (LC) refers to the features present on the earth surface. Land cover configuration is stated as a unified reflection of the existing natural resources and natural processes that are dynamic in nature. Mapping, quantifying, and monitoring the physical characteristics of land cover has been widely recognized as a key element for  natural  resource  management  and sustainable  planning  activities (Nemani & Running, 1996; Barlage et al., 2004). Land use refers to the human induced changes for agricultural, industrial, residential, recreational purposes. The main drivers of land use can be stated as land management policies, population, agricultural production and urban expansion. Land use change alters the homogeneous landscape into heterogeneous mosaic of patches. Almost 40 percent of Earth's land surface had been converted to cropland and permanent pasture by early 1990s,. This conversion has occurred largely at the expense of forests and grassland (Ramachandra and Shruthi, 2007).

LULC change influences the interaction of ecological, geographical, economic, and social factors (Zang and Huang, 2006; Geist and Lambin, 2006). The  impacts of LULC changes  on  a landscape with respect to wind regime, temperature, soil moisture, water vapor, and cloud development has been accounted through numerous models (Adegoke et al., 2007; Narisma and Pitman, 2003; Gero and Pitman, 2006; Sen Roy et al., 2007; Sen Roy et al., 2011). The structure and composition of landscapes undergoes a rapid change as a result of human related activities. The changes in the mosaic of landscape elements are considered to influence significantly the processes and functions of ecological systems. Quantifying landscape spatial patterns and their changes provide important information for monitoring and assessing the effects of human induced changes on landscape.

LULC change detection

Multi resolution data acquired at regular intervals through sensors mounted on space borne platform has been useful in to mapping and monitoring the spatio temporal changes in LULC.  The collection of remotely sensed data covering larger spatial extent enables the analyses of changes at local, regional and global scales over time. This also provides an important link between intensive, localized ecosystem management and sustainable planning (Wilkie and Finn, 1996) and it presents a synoptic view of the landscape at low cost (Lillesand and Kiefer, 1987). Remote sensing data along with GPS (Global positioning system) help in effective land cover analysis (Ramachandra and Kumar, 2004). Successful utilization of remotely sensed data for land cover and land use change detection requires careful selection of appropriate data set. Good quality of RS data, strict geometric registration and radiometric normalization, and suitable training data selection are important for successful implementation of the LULC change detection.