The study area for this survey is considered as urban centers defined in district census book. Sampling frame for urban areas has been prepared by an agency called National Sample Survey Organisation (NSSO) under the Ministry of Statistics and Programme Implementation Government of India. This organization conducts surveys by the name of Urban Frame Survey (UFS). They divide the whole urban centers of a district in blocks called UFS blocks. These blocks are having clear-cut well defined natural boundaries. These blocks are formed on the basis of 600-800 population or 120-160 households and cover the whole area within the geographical boundary of town including vacant lands.
The sampling technique, which is being used is stratified random sampling. The district is divided into five categories of town as defined below, as strata. Urban Frame Survey Blocks (UFS Blocks) are the sampling units. Frame of such blocks for each district are obtained from the National Sample Survey Organisation. The number of sample blocks to be surveyed in the district is to be decided by the following method.
(a) In the district 10 % of total blocks will be selected and proportionately distributed in five class of town when available UFS blocks in the districts are less than 500. Minimum number of blocks should not be less than twenty in a district.
(b) In the district 5 % of total blocks will be selected and proportionately distributed in five class of town when available UFS blocks in the districts are between 500 and 1000.
(c) In the district 2.5 % of total blocks will be selected and proportionately distributed in five class of town when available UFS blocks in the districts are more than 1000. After selecting the UFS blocks, data are collected, entered and processed in the same way as it was done in case of Forest Inventory/TOF Rural.
D. Preparation of Manuals for Forest and TOF Inventory Areas
As per the approval of Tenth Five Year Plan, Forest Survey of India has been entrusted with a new mandate of carrying out inventory of Forest Areas, TOF inventory in rural and urban areas, and estimation of different parameters like Regeneration status, Soil carbon, NWFP and vegetation survey of shrubs, herbs and climbers.
The methodologies for forest inventory and TOF have already been evolved and a field manual has been prepared and communicated to the field units for carrying out inventory. The manual of instructions is primarily meant for the guidance of personnel concerned with field inventory like JTA, STA's, Draftsman, Supervising staff and Data processing officers at HQ's. The manual takes into account almost all aspects involved in the inventory right from the start of survey to the stage of final dispatch of data to the Zonal Head Quarters for entry.
As per Tenth Five Year Plan proposal, FSI will be assessing forest and tree cover in 10% of the total districts of the country in a cycle of two years. Accordingly, 60 districts have been inventoried completely during 2004-2005 and 2005-2006.
Electronic Data Processing
Preparation of National Forest Inventory Database System (NFIDS) As per the Tenth Five Year Plan approval, FSI is conducting National Forest/Tree Inventory along with vegetation survey. As the objectives of the inventory have been redefined with inclusion of several new parameters, the methodology has also been significantly modified. As per the revised methodology a National Forest Inventory Database System (NFIDS) based on database software (MS Access) using front end on Visual Basic has been prepared. The data base system has the following modules:
(i) National Forest Inventory/TOF Data Entry module
(ii) National Forest Inventory/TOF Data Processing module
(iii) National Forest Inventory/TOF Reporting module
(iv) National Forest Inventory/TOF Result database module
(v) GIS interface with forest cover
Work on the first two modules has already been completed and successfully installed in all the zonal offices. Work on the remaining modules is under progress.
Forest Inventory Unit of this organisation processes the data collected by different zones during the inventory through the above modules.