Introduction |
Biomass was the chief source of fuel in the pre industrial revolution world and is still a major source of energy in many developing countries including India. Although biofuel accounts for only 12% of the global energy requirements in terms of total energy content, they cater to the largest section of energy users. It is estimated that two-third of households in the developing countries are still dependent on bioresources for domestic activities such as cooking, water heating, space heating (during winter and monsoon), etc., [1]. Bioresource inventory helps in describing the quality, quantity, change, productivity and condition of bioresources in a given area. These inventories may be for regional or national level assessments [2].
India with a geographical area of about 3.28 million Sq. Km, account for 2.47% of the total geographical area and has 16.1% of the human population and 15.1% livestock population. Seventy percent of India’s population depends on biomass to meet their basic energy needs i.e., fuel, food and fodder. Studies reveal that 85-90% of regional energy consumption in most States in India comes from bioresources. Bioresources ensures provision of energy to the poor and more vulnerable groups. In many regions, there is no realistic alternative to biomass fuels for the poorest portions of the population and also bioresource consumption is still growing. The procurement of energy from biomass is responsible in varying degrees for the ongoing deforestation, and loss of vegetation and topsoil [3]. This necessitates prudent planning of bioresources to ensure its availability to meet the growing demand. The production of biomass in all its forms for fuel, food, and fodder, demands environmentally sustainable land use and integrated planning approach. Detailed planning would be required from national, to State, to District, to Taluk and village levels [4].
Currently available bioresources in Kolar district are under threat of deterioration due to short-term perspectives and narrow sectoral approaches in planning process through indiscriminate pursuit of developmental activities. The changes driven by human activities are directly related to land cover and land use, and have the potential to significantly affect food security and the sustainability of the world agricultural and forest product supply systems. Appropriate policy formulation and planning requires the assessment and forecasting of the demand and supply of all forms of energy. This is required to identify problems and for appropriate intervention options. For this purpose, data on several factors that have an impact on an energy system is needed. A regional database on bioresources is needed to support the information requirements of the regional energy planning for sustainable development. However, for most parts of India these data are not available for planning. The production, distribution and consumption of bioresource occur usually at local level, on a small scale and often outside the monetary economy. The environment, the level of income, the type of settlement and the existence and accessibility of resource vary among areas, the supply of biomass and energy consumption varies spatially. Like wise within an area, pattern of energy demand and supply can vary by sub-area, town, or village, depending on cultural, social, geographic, agro-ecological and climatic conditions. The bioresource assessment is based on detailed field investigations to estimate the available bioresources and demand spatially in Kolar district of Karnataka state, India for evolving better management strategies and ensure renewability of resources. In this regard spatial tools such as GIS and remote sensing data help immensely in providing geographically referenced spatial distribution of potential and demand.
Remote sensing is the practice of deriving information about the earth’s land and water surface using images acquired from an overhead perspective, using electromagnetic radiation in one or more regions of the electromagnetic spectrum, reflected or emitted from the earth’s surface [5]. RS systems offer four basic components to measure and record data about an area from a distance. These components include the energy source, the transmission path, the target and the satellite sensor. The energy source, electromagnetic energy, is very important. It is the crucial medium required to transmit information from the target to the sensor.
RS sensors (airborne or space borne) aid in acquiring the spatial data of the earth or its parts at frequent intervals, which are required for sustainable management of natural resources. It provides synoptic coverage of resources at regular intervals, which help in mapping and classification of land cover features, such as vegetation, soil, water and forests. It helps in assessing the extent and diversity of vegetation. Also, it aid in estimating how factors such as moisture, latitude, elevation above sea level, length of the growing season, solar radiation, temperature regimes, soil type and drainage conditions, topographic aspect and slope, prevailing winds, etc., influence vegetation [6].
RS technology has emerged to support data collection and analysis methods of potential interest and importance in resource sustainable management so as to satisfy the expressed desire or goal that resource management succeeds in maintaining the ecosystem in a sustainable condition [7]. Sustainable development of a region requires a synoptic ecosystem approach that relates to the dynamics of natural variability and the effects of human intervention on key indicators of biodiversity and productivity [8]. Inventory and mapping of resources are today facilitated by remotely sensed imageries. The multispectral images are used for quantification and monitoring of resources and analyse changes over a period of time. An important aspect of remote sensing data is that it helps in quantitatively deriving the biomass variation from the high dimensional data collected from multi-frequency (multi spectral), dual-polarized, multi-day, multi-angle, and passive sensors. Geographical information systems (GIS) help in archiving, analysis and visualistaion of remote sensed data along with other collateral data (spatial as well as statistical). Remote sensing data along with GIS and GPS (Global positioning system) help in land cover and land use analyses as well as species level mapping (using higher spatial and spectral resolution data).
Land cover refers to the physical characteristic of the earth’s surface, captured in the distribution of vegetation, water, desert, ice, and other physical features of the land including those created solely by human activities [9]. Land use is defined as the use of land by humans, usually with emphasis on the functional role of land in economic activities. In a much broader sense, land cover designates the visible evidence of land use, to include both vegetative and non-vegetative features [5]. The analysis of vegetation and detection of changes in the vegetation pattern on spatial and temporal scales are keys to the natural resource assessment and monitoring. Thus the detection and quantitative assessment of vegetation is one of the major applications of remote sensing for environmental resource management and decision-making. Land cover analysis is done using vegetation indices (VI’s) and land use analysis using classification techniques.
