Use of Landsat TM data in location of sites for afforestation
programmes in India*
T.S. Kachhwaha
Remote Sensing Applications Centre, U.P.
Sector G, Jankipuram, Kursi Road,
Lucknow 226 007, India
Abstract
The forest cover of the country and specially that of Uttar Pradesh as much less than recommended in the National Forest Policy approved by Government of India in 1952. According, vigorous afforestation and social forestry programmes have been launched to increase the tree cover. One of the important aspects of these programmes is the selection of suitable location which can be acquired with ease without necessarily changing the present landuse which may there wise lead to socio-economic problems. Therefore, the best location for afforestation programmes in the first instance, would be those degraded lands which be not suitable for agiculature and are currently lying waste, followed by the degraded forest lands. This would not only increase the productivity of such land but would also lead to qualitative improvement of such degraded lands.
In the present study, Landsat - 5 Thematic Mapper (TM) data acquired on February 23, 1986 has been used. False Colour Composite (FCC) on 1:50,000 sale has been visually interpreted to identify and delineate degraded lands which could be utilized for afforestation and social forestry programmes.
Introduction
The forest wealth of the country is known to have depleted to a large edent in the past. Deforestation has resulted in a series of degradation processes philately leading to various kinds of environmental hazards, which not only depletes the biomass reserve but also degrades the land, affects the climate and disturbs the water balance of the area. Frequent periods of floods and droughts are the resultant effects of deforestation which ultimately influences the human and animal population to a great extent.
NRSA (19823), based on the satellite data of 1972-75 and 1980-82, has imported that forest cover in Uttar Pradesh was depleted by 1.65% in intervening 7 years and in the year 1982 it was only 7.14% of the total geographical area. Mishra et al. (1985), based n satellite data of 1981-83, have reported 11.29% first cover in Uttar Pradesh. In the Forest Statistics of U.P. (1983), State forest Department has however, reported 17.41% forest cover in Uttar Pradesh. These figures, although, mutually contradictory, do indicate an alarming situation of forest degradation. Evidently all these estimates are much less than recommended in the Nation Forest Policy approved by Government of India in 1952 which states that on an average 33% of total geographical area of the country should be under permanent forest cover.
Until about a few years ago, there was a lack of comprehensive awareness of the degradation of forest cover and the resultant consequences. During the lat decade, however, vigorous efforts have been made to rehabilitate the first cover through launching of afforestation programmes. These programmes can be implemented well only if the problems related to these programmes are well understood. One of the important aspects of such programmes is the location
of those areas where such schemes can be implemented without adversely affecting the present landuse. This is particularly necessary because most of the forest land, encroached in the past, is currently being used for agriculture.
Since it is not possible to lead to status quo ante, it is imperative that such schemes are either taken up in degraded forest lands or on those lands which are currently not being put to any use but lying waste. It is possible to identify and map such lands where social forestry and afforestation programmes can be undertaken more effectively. This would not only increase the wooded area to meet ever increasing demand of timber, fuel wood etc., but would also simultaneously improve these lands. Perhaps even more important aspect of these programmes is the continuous monitoring of the afforested area. While the programme of tree plantation is generally executed satisfactorily, the rate of survival and plant growth which play an important role in the evaluation of these schemes is generally ignored in computing the statistics. It is thus essential that, apart from monitoring afforested areas, temporal assessment of wooded area should also be undertaken.
Satellite remote sensing technique is very effective in obtaining an accurate information on both the aforesaid aspects with minimum of turn-around time. It thus provides an excellent monitoring system in a cost effective manner. In fact the conventional methodologies can not provide a matching monitoring system. In the present study, an area of approximately 620 sq km has been selected in Fatehpur district, Uttar Pradesh, as a test site to demonstrate utility of remotely sensed satellite data for mapping those areas where afforestation programme can be undertaken. Monitoring capabilities of satellite remote sensing have already been amply demonstrated in eastern U.P. (Kachhwaha, 1985).
* Present at 11th Asian Conference on Remote Sensing held at Zhongshan university, Gaungzho, China, November 15-21, 1990.
