Biodiversity Impact Assessment Report
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BIODIVERSITY IMPACT ASSESSMENT REPORT INTRODUCTION Ecology is a branch of science which dealing the relations and interactions between organisms and their environment. An ecological survey of the study area was conducted, particularly with reference to listing of species and assessment of the existing baseline ecological conditions in the study area. The main objective of biological study is to collect the baseline data regarding flora and fauna in the study area. Data has been collected through extensive survey of the area with reference to flora and fauna. Information is also collected from different sources i.e. government departments such as District Forest Office, Government of Rajasthan. On the basis of onsite observations as well as forest department records the checklist of flora and fauna was prepared. Objectives of Biological Studies The present study was undertaken with the following objectives: To assess the nature and distribution of vegetation in and around the project site (within 10 km. radius). To assess the animal life spectra (within 10 km radius). To achieve the above objectives a study area was undertaken. The different methods adopted were as follows: (i) Compilation of secondary data w ith respect to the study area from published literature and various government agencies. (ii) Generation of primary data by undertaking systematic ecological studies in the area. (iii) Discussion w ith local people so as to elicit information about local plants, animals and their uses. (iv) Generation of Primary Data. (v) To prepare a general checklist of all plants encountered in study area. This would indicate the biodiversity for wild and cultivated plants. Phyto-sociological Study A quadrat study was taken for woody and herbaceous flora in core and buffer zone (within 10 km. radius of the mining site). Ecology of the Study Area Phyto-sociological studies of the region evident that the region is sparsely vegetated. During the field visit, the site is almost barren with few thorny vegetation including shrubs, herbs and trees. Site surveys indicate that the mining activities will have shown impacts on the biological environment. The general topography and vegetation pattern of site is inevitably no changed by proposed mining activities. During transportation, dust will arise due to vehicular movement. Therefore, indigenous plantations are necessary for the restoration of riparian zone (erosional prone zone) and along haul roads and other unworked areas towards improving the biological diversity. Phyto-sociological Study Plant and animal communities are indicators of the environment. They respond not only to one environmental factor, but also to an interacting group of factors. The plant and animal communities integrates these influences and reacts sensitively to changes in the balance of environmental stresses such as abiotic and biotic factors and anthropogenic activities. This could cause changes in the physiognomy, structure and species composition of the flora and fauna. Ecological integrity is one of the fundamental factors towards attaining a sustainable ecosystem following biological study around the mine lease areas was undertaken to assess the species diversity, distribution and present status of flora and fauna. Floral and faunal surveys for assessing biological diversity and its status over a period of time form an integral part of impact assessment study. In an environment impact assessment study, identify the baseline of relevant parameters which are likely to be affected as result of operation of proposed project of river sand mining. For this a detailed environmental study has been conducted for river sand mining project in the area. Vegetation types and its distribution The study was aimed at enumeration of the available plant resources and obtaining a broad representation of the existing floristic variations in the mine lease area and surrounding mine lease areas. Enumeration of the plant wealth was done by surveying the area through walking followed by collection and identification of plant specimens. Phyto-sociological aspects of the study were carried out by perambulating and sampling through quadrates method. Sample plots were selected in such a way to get maximum representation of different types of vegetation and plots were laid out in different parts of the areas within the mine area as well as the surrounding mine area. Selection of sites for vegetation data was done by random sampling procedure. Accordingly, equal number of quadrates of 10 m x 10 m for the study of tree layer in the mine lease area and surrounding mine lease area were laid. Within these sample plots, sub-plots of 3m x 3m were laid out randomly for studying the shrub layer and regeneration of tree species. For information on ground layer including herbaceous species, quadrates of 1 m x 1 m size were laid out within the tree quadrate. All species encountered during the transect walk were recorded and their herbarium specimens prepared for identification and future use. The girth at breast height (gbh) of all individuals in each quadrate was measured for all species of trees and woody climbers. All individuals w ith gbh> 10 cm were considered. Individuals below 10 cm gbh were considered as saplings and shrubs. This concept was tested further during the fieldwork. Basal area of plants was measured following Philips (1959). The plants were identified using floras by Haines (1921-25), Saxena and Brahmam (1994-96). The primary data recorded on number of individuals in a species and girths were utilized to derive secondary attributes like density and frequency following standard phyto-sociological methods of Misra (1968). Relative values were calculated following Philips (1959). Important Value Index (IVI) was calculated by adding up relative frequency, relative density and relative dominance (Curtis, 1959). In the case of shrubs, herbs and saplings; IVI was calculated based only on relative values i.e., relative frequency and relative density. Formulae used for various calculations are: Total number of individuals of a species Density (D) = Total number of quadrats studied Number of quadrats of occurrence % Frequency (F) = x 100 Total number of quadrats studied. Number of individuals of a species Relative Density (RD = x 100 Total number of individuals of all sp ecies Number of occurrence of a species Relative Frequency (RF) = x 100 Total number of occurrence of all species Total basal area of a species Relative Basal Area (RBA) = x 100 Total basal area of all species Importance Value Index (IVI) = Relative Density + Relative Frequency + Relative Dominance Flora of Mine Le ase Area (Core Zone) Floristic composition varies depending upon the site and its environmental features and it is one of the major characteristic features of any plant communities. The flora of the mine lease area dominated by Prosopis and Calotropis vegetation consisted. Biological Environment An ecological study of the ecosystem is essential to understand the impact of industrialization and urbanization on existing flora and fauna of the study area. Studies on various aspects of ecosystem play an important role in identifying sensitive issues for undertaking appropriate action to mitigate the impact, if any. The biological study was undertaken as a part of the EIA study report to understand the present status of ecosystem prevailing in the study area, to compare it with past condition with the help of available data, to predict changes in the biological environment as a result of present activities and to suggest measures for maintaining its health. A survey was conducted to study the flora & fauna in 10 km radius. Some of the information was gathered from the local habitants. All the collected data were classified to interpret the impact of pollution on the flora and fauna of that region. Survey of the wild plants as well as cultivated crop plants was made and all the available information was recorded. Methods used for identifying flora and fauna are given in Table Sampling Methodology for Flora and Fauna Taxonomy Sampling Methods Plants Quadrate sampling and enumeration Butterflies Transect, Visual encounter survey Amphibians Visual encounter survey (search) Reptiles Visual encounter survey (search) Birds Point count, opportunistic observation Mammals Tracks and signs, and visual encounter survey Flora in Study Area A general floral survey was carried out for the study area. List of flora found in the core zone and buffer zone is given in Table List of Flora in the Core Zone S .No. Vernacular Name Scientific name Family A. Plants 1. Neem Azadirachta indica Meliaceae 2. Dhak Butea monosperma Fabaceae (Papilionaceae) 3. Gulmohar Delonix regia Caesalpiniaceae 4. Imli Tamarindus indica Fabaceae (Leguminosae) 5. Pipal Ficus religiosa Moraceae 6. Ker Capparis decidua Forsk. Capparidaceae 7. Bargad Ficus bengalensis Linn. Moraceae 8. Babool Acacia nilotica Fabaceae (Mimosoideae) 9. Avla Emblica officianalis Gaerth. Euphorbiaceae 10. Aritha Sap indus emarginatus Valh Sap indaceae 11. Ardu Ailanthus excelsa Simaroubaceae 12. Siris Albizia lebbeck Mimosaceae Shrubs 1. Vilayati babool Prosop is juliflora Mimosaceae 2. Nagphani Opuntia dillenii Cactaceae 3. Aakra Calotropis gigantea Asclepiadaceae Herbs 1. Dhatura Datura metel Solanaceae 2. Badi Dudhi Euphorbia hirta Euphorbiaceae 3. Sunflower Helianthus annus Asteraceae 4. Gokhru Parthenium hysterophorus Asteraceae (Comp ositae) Grasses 1. Anjan Cenchrus ciliaris L Poaceae 2. Gramna Panicum antidotale Petz. Poaceae