("hapter 2: Study Area. 2.1 Rajasthan- The Desert State

Transcription

1 CHAPTER 2 STUDY AREA 2.1 Rajasthan - The Desert State Geographic location and Physiography The western and north-western desert or Thar The Aravali and hilly range The south-eastern plateau (Hadoti Plateau) Eastern Plains The major river basins 32 2 J Climate Temperature Variability Rainfall Distribution Soils Vegetation Fauna Socio-economic set up Problem Identification 54

2 ("hapter 2: Study Area 2.1 Rajasthan- The Desert State Rajasthan perceived as the Desert State of India has widely contrasting topography. It is immensely rich in natural beauty and its beautiful forests and valleys are as famous as its desert. Geographically, no other region can claim greater diversity than Rajasthan - a region of lofty hills and rolling sand dunes, of scorching heat and freezing cold, of fertile plains in die east and sparsely populated areas of Jaisalmer in die west it is die largest state in the country presenting a kaleidoscope of ecosystems. Rajasthan is one of the 21 states of India and shares its geographical boundaries with the states of Punjab, Haryana, Uttar Pradesh, Madhya Pradesh and Gujarat. Its northwestern and western regions, comprising 11 districts covering 61 per cent of the total area and 40 per cent population of the State, form the "Great Indian Thar Desert". The State, in its present form, came into existence as a conglomeration of 19 princely states and 3 chief ships, which varied in size, administrative efficiency and socio-economic development at the time of the formation of the State. Figure 2.1 Geographic location of the study area with district administrative boundaries 27

3 Presently, it is divided into 33 districts, which are further divided into 241 tehsils, 183 municipalities, 237 Panchayat Samities and 9,184 village panchayats. Rajasthan is one of the most fascinating regions of the world witnessing one of the oldest civilizations with an extremely rich cultural heritage. It is a predominantly agrarian state where agriculture contributes about 25 to 40 per cent of the State's Domestic Product, and about 70 per cent of the population is engaged in agriculture and allied activities. The main crops of the State are food grains, pulses and oilseeds. The State has emerged as a leading oilseed producer in the case of rapeseed, soybean and mustard. People of Rajasthan are commonly known as Marwaris. The language prevalent is Marwari and mixed Hindi. Most of the area in Rajasthan is arid and suffers acute tropical climate and the vast desert of Thar is spread wide over the state. The people of Rajasthan are very efficient in trade and commerce. Having a unique knack and tactic in trade, they are widely popular as the masters of business. Jaipur, the Pink City and Udaipur, the city of palaces, are places historically most prominent. 2.1 Geographic location and Physiography The arid and semi-arid regions of Rajasthan (covering the entire Rajasthan state), lies approximately between 23 3' N to 30 12' N latitude and between 69 30' E to 78 17'E longitude on the globe, occupying an area of about 3,42,239 sq km (130,000 sq. miles). Rajasthan can be broadly divided into four physiographic units: a) western and northwestern desert or Thar and b) Aravali and hilly range c) Eastern plains region and d) South-eastern plateau. The distinct landforms west/north-west and east/ southeast to the Aravali range results in a unique climatic set-up, soils and vegetation. 28

4 The southern and eastern Rajasthan are relatively more fertile areas and forms the Basin of Chambal River with its tributaries Banas, Kalisind and Parbati. The western region is a desert with only one river Luni, arising southwest of Ajmer and joins the Rann of Kutch after covering a distance of 200 miles. 1 Figure 2.2 Physiographic regions of Rajasthan The western and north western desert of Thar The Great Indian Desert tract of Rajasthan, known as Thar of the Rajputana consists mainly of wind blown sand dunes. It covers an area of 40,000 sq. miles approximately 61% of the Rajasthan; it stretches from the west of AravSnT to the basin of the Indus and from southern Rann of Kutch to the Punjab plains The desert area is covered not only by the sheet of sand but some rocky projections of 19

5 low elevation from the older rocks of the country are also seen. A thick series of sedimentary rocks comprising sandstone, limestone and shales are the important lithological formations of the region. The deposition of these rocks in western Rajasthan was preceded by igneous activity, which included a thick pile of lava mostly of an acidic nature. The plutonic equivalent of this lava could be seen in the form of granite bosses and sills in Jalore, Siwana, Mokalsar and Jodhpur areas. On the basis of the controlling features like the Aravali hills and the rocky terrain of Barmer-Jaiselmer-Bikaner tract, the desert can be conveniently divided into several natural regions of NNE-SSW belts. The dunes of Rajasthan desert are of three types: (a) longitudinal dunes, (b) barchans, and (c) transverse dunes. The longitudinal dunes run NNE-SSW, parallel to prevailing winds, which occur to the south and west. The barchans have concave sides facing the wind in the interior direction while the transverse dunes are aligned across the wind direction to the east and north. Big trees on the leeward side of the transverse dunes are indicative of stabilisation for a considerable time. Three types of topographical features are met with in this region having a bearing on both the types of vegetation and formation of sand dune. It has been also observed that the sand dunes are generally not of a shifting nature due to the stabilising effect of some vegetation prevailing on them but due to excessive vegetation degradation and consequently the exposure of the sand surface has resulted in shifting of dunes The Aravali and hilly range The Aravali hill ranges are the oldest mountains of India and are the most dominant hilly area of Rajasthan. These ranges run diagonally across the state from northeast Delhi to southwest up to the plains of Gujarat, covering a distance of about 692 km. Within Rajasthan, the ranges run from Khetri in the northeast to Khed Brahma in the southwest for a length of about 550 km. In the northeast, the hill ranges become 30

6 more prominent near Khetri and Alwar. Towards the southwest, the ranges become more prominent with peaks up to 1055 m above mean sea level (msl). The Aravali range divides the Rajasthan State into two distinct regions. Towards the north and northeast is the vast desert and towards the south and southeast is fertile plains and plateau. It is also a major water divide. The area to its east is well drained by several integrated drainage systems, while the area to the west has only single integrated drainage system, which is the Luni drainage system in the southeastern part of the desert. The average height of this region is 600 meters above msl, and highest at Guru Shikar in Mount Abu (1727 m). Mewar hills and Marwar hills are the some of the offshoots of Aravali The south-eastern plateau (Hadoti Plateau) Southern and southeastern part of Rajasthan is mostly a plateau, commonly known as the Hadauti plateau. It has intrusions of black volcanic rocks into the Vindhyans and extends to a great part in Jhalawar, Baran and Kota districts. The entire rock system of the southeastern region belongs to the metamorphic series of Archaean rocks and consists of guein, biotite, schists, quartites and limestone with frequent bandings of marble and granite. The southeast of this region is represented by stratified sandstone except some small patches of limestone beds, which are found near Anta 30 miles east of Kota. Sandstone deposits are of more recent origin in comparison to shale or limestone. This geological formation is referred to come under upper Vindhyan or Cambrian system (Rewa series). The Malwa plateau also extends into the southern part of Rajasthan in Chittorgarh and Banswara districts having an average altitude of 500 m above msl. This region is dotted with isolated low ranges at few places. The plateau in Rajasthan occurs in the upper catchment of the Chambal River to the southeast of the Mewar plains. The greater part of this area is drained by the river Chambal and its right bank tributaries like Kali Sindh, Parwan and Parvati. 31

7 2.2.4 Eastern Plains The eastern plains covering the most part of Alwar, Bharatput, Sawai Madhopur, Bundi and Kota districts are rich in alluvial soils, which are drained by seasonal rivers, the three important being the Chambal, the Banas and the Mahi. The Chambal River Basin extends over parts of Chittorgarh, Bhilwara, Bundi, Sawai Madhopur, Tonk, Jhalawar, Kota, Baran and Dholpur Districts. The Banas River is the major tributary of the Chambal River, which ultimately joins the river Yamuna. The total catchment of the Chambal Basin is 77,293 sq.km including the catchment area of Banas Basin. The alluvium deposits become thin towards west where the plain is higher and more irregular, while in the east the thickness of alluvium increases. The southeastern part of Udaipur, Banswara, Dungarpur and southern part of Chittorgarh districts is of the Chappan plains. The area is drained by tributaries of Mahi River, which ultimately reaches the Arabian Sea through the Gulf of Cambay. It lies south of Banas Basin, its eastern edge borders Chambal Basin in Madhya Pradesh, and its western edge borders Sabarmati Basin The major river basins The Chambal, the Banas, the Luni, the Mahi, the Sabarmati, the Ruparail, the Banganga are important rivers of Rajasthan forming fifteen river basins. These are the Chambal, the Banas, Luni, Mahi, Sabarmati, Shekhawati Ruparail, Banganga, Gambhir, Parbati, Sabi, West Banas, Sukli, other nallas of Jalore and the Outside Basin The Chambal River Basin is located in eastern Rajasthan and extends over parts of Chittorgarh, Bhilwara, Bundi, Sawai Madhopur, Tonk, Jhalawar, Kota, Baran and Dholpur Districts with a total catchment area of 31,460 sq km (excluding Banas Basin, which is also a tributary of Chambal). The Banas River Basin is located in east-central Rajasthan and aligned in NE-SW direction, it is bounded by the Luni Basin in the west, the Shekhawati, Banganga and Gambhir Basins in the north, the 32

8 Chambal Basin in the east, and the Mahi and Sabarmati Basins in the south. The Banas Basin extends over parts of Jaipur. Dausa, Ajmer, Tonk, Bundi, Sawai Madhopur, Udaipur, Rajsamand, Pali, Bhilwara and Chittorgarh Districtsand has a total catchment area of the Basin is 45,833 sq km. The western part of the Basin is a hilly terrain belonging to the Aravali chain while on the eastern side of the hills lies an alluvial plain with a gentle eastward slope. In the western Rajasthan the Luni River is the only major river with a total catchment area of 37,363 sq km. Luni River Basin is located in south-western Rajasthan. The total length of Luni is nearly 805 km, having a depth 2.4 m, and width m and an average slope of 1 in The Lilri, the Mitri, the Sukri, the Guhiya, the Bandi. the Jojri, the Sagi and the Jowai are the major tributaries of the Luni river all of them joining it from the left. The Basin extends over parts of Ajmer, Barmer, Jalore, Jodhpur, Nagaur, Pali, Rajsamand, Sirohi and Udaipur Districts. The greatest peculiarity of the Luni in the western Rajasthan is that it tends to increase its width rather than deepening the riverbed, because the floods in the region develop so rapidly and in such a short time that they get no time to scour the bed. Instead of taking its normal course the Luni river spills over to country and divides itself into several channels. Because of the sand dunes in the west, it reduces itself to a single stream before falling into swamp. The water of River Luni is sweet up to Balotra and becomes more and more saline further downstream. The other important river systems in the desert region are the Badgaon River basin and other nallas in Jalore district and the Shekhawati Basin in Sikar and Jhunjhunu districts. These rivers are the part of the outside basin. The arid area of the inland drainage is known as the Outside Basin and lies in the western and northern part of Rajasthan covering about 49% of the total area of Rajasthan. The Outside Basin is a closed basin and the drainage is ill defined, originating and ending within the plain itself. Because of the scanty rainfall, the streams carry only peak floodwaters. 33

9 River Basins of Rajasthan \ Outside Basin Shekhawat, >aw, R ^P "' 6^' 1 Besin Rsnganga Basin GambHir feasir Parbati Basin Other Nallabs imahi Basin Sabarmati Basin i^, ^ jfeal* BWI I /vy International Boundary ^ stale Boundary ^x/ I River Basin Boundary Figure 2.3 Major River Basins of Rajasthan

10 The Mahi River Basin and the Sabarmati River basin are the important basins of southern and southeastern Rajasthan. Mahi River Basm extends over parts of Banswara, Chittorgarh, Dungarpur and Udaipur Districts having a total catchment area of 16,985 sq km. The Sabarmati River rises in the Aravali hills, which roughly mark the western boundary of Udaipur District, and flows in a southwesterly direction. The Wakal River and the Sei Nadi are the main tributaries of the Sabarmati River, which also rise in the Aravali hill range west of Udaipur City. The Sabarmati River Basin extends over parts of Udaipur, Sirohi, Pali and Dungarpur districts with the total catchment area of the 4,164 sq km. The important river basins in the northeastern part of Rajasthan are the Ruparail, the Banganga, and the Gambhir river basins. 2.3 Climate The climate of Rajasthan varies from arid to sub-humid types. The climate in the west of the Aravali is characterised by low rainfall and erratic distribution, extremes of diurnal and annual temperatures, low humidity and high wind velocity. While the climate in the eastern side of the Aravali range is semi-arid to sub-humid. It is characterised by more or less the same extremes in temperatures but relatively lower wind velocity and high humidity with better rainfall. The entire state is characterised by hyperthermic (high temperature) conditions. The variability in the climate west to east is also exhibited in vegetation distribution, type and function. While the vegetation of western Rajasthan is typical xerophytic the vegetation in the eastern part is broadleaved deciduous. 35

11 Agroclimatic Zones booooo 6OO0O O00OO O OO0OO S0OOO Semi arid northern plains N At id western plain Transitional plain of inland drainage Flood prone eastern plain Semi-arid eastern plain.si."..! Transitional plain of Luni basin Sub-humid southern plain and Aravalli hills Humid south-eastern plain rn plain IWOOOO ^m\t 1: Kilometers Figure 2.4 Agroclimatic Zones of Rajasthan 36

12 2.3.1 Temperature Variability Marked variations have been observed in diurnal and seasonal range of temperatures at all the places in the state, which exhibits the most characteristic phenomenon of the warm-dry continental climate. The summer starts in the month of March the temperature starts rising progressively through April, May and June. The temperature rise during this period is almost uniform all over the state. In the western part, mainly at Bikaner, Phalodi, Jaisalmer and Barmer, the maximum daily temperature varies between 40 C to 45 C, occasionally, rising up to 49 C. However, the minimum daily temperature drops down considerably at night and remains between 20 C to 29 C. In the eastern side of the Aravali range, the temperatures during daytime are in a similar range but night temperature hover around 26 C. The daily mean temperature at Udaipur and Mount Abu in summer, are relatively lower reaches 38 C and 31.5 C, respectively. The daily minimum temperature for these two stations is around 25 C and 22 C, respectively. The isotherms of summer (June) show variations from 42 C (Sirohi district) to above 47 C (Ganganagar district) (Figure). The arid zone of the west and the semiarid zone of the mid-west, which comprises the major part of the state, have an average maximum of 45 C in this month and in the south-eastern parts, the isotherms show a declining trend from 43 C to 37 C. The coldest month of the year is January but the winter season starts from December and remains through February with marked decline in minimum temperatures in December and January. The minimum temperatures may fall to minus 2 C in the night at some places like Sikar, Churu, Pilani and Bikaner. On account of quick release of thermal radiation from the sandy soil soon after dusk there is a sharp decrease in night throughout the arid and semi-arid zone of western Rajasthan. At the same time occasionally occurring secondary western disturbances, may also lower the night temperatures and increase wind speed creating wind-chill effect. 37

13 The isotherm of winter (January) ranges from less than 6 C in the north to above 10 C in the southeast. The greater part of Rajasthan, except the southeastern part of Kota, Bundi and Baran and the western district of Barmer exhibits the mean temperatures of more than 10 C. The secondary depressions (western disturbances) accompanied by the ice-cold winds, emanating from the higher latitudes, may bring entire Rajasthan under the spell of the cold wave for the periods of 2 to 5 days during winter months Rainfall Distribution The annual rainfall varies significantly and the general trend of Isohytes is from northwest to southeast. A rapid and marked decrease in rainfall is observed in the west of the Aravali range, which makes western Rajasthan the most arid part of the country. The average annual rainfall in this region ranges from less than 10 cm in northwest part of Jaisalmer (lowest in the state), to 20 to 30 cm in Ganganagar, Bikaner and Barmer regions. From 30 to 40 cm in Nagaur, Jodhpur, Churu and Jalor regions and more than 40 cm in Sikar, Jhunjhunun and Pali regions and along the western fringes of the Aravali range. The eastern side of the Aravali range experiences the rainfall from 55 cm in Ajmer to 102 cm in Jhalawar. In plains, Banswara (92.0 cm) and Jhalawar (95 cm) districts receive the maximum annual rain. Mount Abu (Sirohi district) in the southwest, however, receives the highest rainfall in the state (163.8 cm). The yearly total rainfall is highly variable at different places all over the state and it is most erratic in the western half with frequent spells of drought, punctuated occasionally by heavy downpour in some years, associated with the passing low pressure systems over the region. The southwest monsoon, begins in the last week of June in the eastern parts, and ends till mid-september. There are pre-monsoon showers in the middle of June and post-monsoon rains occasionally occur in October. A little rainfall associated with the passing of western distribution over the region results in some winter rainfall. 38

14 Rainfall Variability ooooo soooon laooonc iiooooo iflooooo Mean Annual Rainfall in cms Scale 1 *io J 1*20 S 3W0 j ifc b&60 GO r c Meters I J 160 tab 1: I /^/ I International Boundary ] State Boundary Figure 2.5 Mean annual rainfall distribution pattern in Rajasthan 39

15 The highest normal monthly rainfall is during July and August at most of the places and the number of rainy days during this period varies widely in different places, ranging from 10 in Jaisalmer to 40 in Jhalavvar and 48 in Mount Abu. Rainfall in mm 1200 Fluctuation, in tlonsoon rain-fall for Chaksu, S Year Figure 2.6: Annual rainfall variation at Chaksu for 100 years The rainfall distribution pattern observed at Chaksu shown in the above figure indicates the high variability in rainfall over the 100 years. While the minimum amount of rainfall observed in past 100 years was approximately 100 mm, the maximum amount was 1200 mm. Thus the difference between the minimum and maximum amount of rainfall observed over these 100 years is of the order of 1100 mm approximately. 2.4 Soils Tk UTLG The soils of Rajasthan are complex, and highly variable, reflecting a variety of differing parent materials, physiographic land features, range of distribution of rainfall and its effects, etc. However, broadly, the soils can be put in five major groups, based on the basic fabric of soils i.e. soil texture which governs its many 40

16 other properties. They are, (1) sandy soils or light soils, (2) sandy loam or light medium soils, (3) loam or medium soils, (4) clay loam to clay or heavy soils and (5) skeletal soils or shallow rocky and hilly soils, which are further categorized as: a) Desert Soils cover the State from the west of the Aravali up to the border with Pakistan. Water is scarce in this region. The soils contain 90 to 95 per cent sand and about 5 to 7% clay. This type of soil is formed by windblown sand from the coastal regions. It is poor in organic matter. However, it contains high quantity of nitrogen in the form of nitrates. Phosphates together with nitrates make the desert soils fit for agricultural crops, wherever water supply is available. b) Red and Yellow Soils are poorer in carbonate and humus content. Calcium carbonate is absent. Salt content is low. The surface colour of the soil varies from place to place. It may be light yellowish, brown yellowish or dark brown. c) Grey Brown (Desert Soils) is found in districts of Barmer, Jalore, Jodhpur, Sirohi, Pali Nagaur, Sikar and Jhunjhunu. It contains nitrogen that makes it fertile. d) Ferruginous Red Soil is found in Udaipur and Dungarpur districts. This soil is poorer in nitrogen, phosphorous and humus. e) Mixed Red and Black Soil is found in the eastern parts in the districts of Udaipur, Chittorgarh, Dungarpur, Banswara and Bhilwara. f) Medium Black Soil is mostly found in Kota, Bundi and Jhalawar districts. It may be heavy, medium heavy and yellow and red light. Organic carbon and nitrogen are low to medium level in this soil. 41

17 g) Alluvial Soils are mostly found in the northeastern part of the state in the districts of Alwar, Bharatpur, Jaipur, Sawai Madhopur and the central part of Ganganagar district. They are deficient in lime, phosphoric acid and humus. This soil produces a large variety of crops including wheat, rice, cotton and tobacco. Soil erosion is a major problem faced by Rajasthan. Development of forests and grasslands are the solutions to this problem. 2.4 Vegetation The vegetation of Rajasthan varies from dry tropical forests to desert thorn scrubs and grasslands following the physiography, temperature and rainfall distribution. The major vegetation types as described by Champion and Seth (1968) and Shankar and Kumar (1988) for Rajasthan are: Subtropical hill forest, Dry/very dry teak forest, Dry mixed deciduous forest, Dry deciduous scrub, Anogeissus pendula forest, Dry tropical riverain forest, Mixed xeromorphic thorn forest, Mixed xeromorphic woodland, Mixed xeromorphic riverain thorn forest, Lithophytic scrub desert, Psammophytic scrub desert, Halophytic scrub desert. The major forest types have been described using the classification of Champion and Seth, however the thorn forest and thorn scrub types as identified by the Champion and Seth has been further categorized using the classification of Shankar and Kumar. a) Subtropical hill forest The forest due to exposure and often with poor soil, long subjection to human pressure and grazing is mostly an inferior type with trees being short boled and branchy. It is therefore doubtful if any climax forests survives though the vegetation of sheltered glens and steep and narrow gullies probably represent it to 42

18 some extent. The average sites carry more xerophytic vegetation, which in its present and degraded form closely resembles the tropical dry deciduous forest though with a higher proportions of evergreens. In Rajasthan this type of forest is found in Mount Abu, however now no subtropical evergreen is found and only some of the higher valleys include Syzygium cumini, Ixora arborea, Strobilanthus spp., along with the numerous species of Himalayan origin, which suggests subtropical conditions. b) Dry/very dry Teak forest Mixed dry deciduous forest with teak forming the major proportion of the forest on shallow porous or stiff clayey soils has been identified as dry teak forest. The other characteristic species are Anogeissus latifolia, Diospyros tomentosa, Hardwickia binata and other common dry deciduous trees. This forest type is found in the Banswara division of Rajasthan. Along with this type very dry and open forest of Tectona grandis is also found in Banswara, Chittorgarh and Udaipur regions with Tectona as dominant species and Boswellia serrata, Anogeissus latifolia, Sterculia urens, Chchlospermum religiosum, Acacia catechu, and occasionally Anogeissus pendula especially in transition zone. Dendrocalamus strictis is also present along with shrub species such as Carissa, Helicteres etc., and grasses like Apluda mutica, Themeda spp., Ergrostis spp., Andropogonpumilus, Aristida spp., etc. c) Dry mixed deciduous forest The extensive consociations of Anogeissus latifolia, Boswellia serrata and Cleistanthus colinus are the characteristic feature of this type of forest. However, in most localities tree canopy has been seriously broken by human activities and scattered tree and small groups have become typical feature of these forests. The 43

19 other associated species are Linnea coromandalica, Terminalia spp., Albizzia spp., Diospyros melaxylon, Sterculia urens, Mitragyna parvifolia, Butea monosperma, Ficus spp.. Acacia spp., etc. This type of forest is mainly spread in Chittorgarh and Udaipur districts of Rajasthan. In Rajasthan this forest type and Anogeissus pendula type forest occur in close proximity with practically no transition, which is not the case generally and Anogeissus latifoua and pendula are not found together although their associates are in common. Anogeissus latifolia is prominent on flat tops in association with Boswellia, Linnea and Acacia and in southern aspect with Boswellia, Sterculia and Nyctanthes. d) Dry deciduous scrub The dry deciduous scrub represents the degradation stage of the dry deciduous forests. It is characterized by low broken soil cover of 3 to 6 meters high shrubs including some tree species reduced to shrubby growth with many stems growing out from the base. Some bamboo is often present along with thin grass throughout the forest. Most of the shrubs like Holarrhena, Dodonaea are distasteful while others like Randia and Carissa are thorny and therefore not palatable for cattle. This type of formation is found in the Banswara region with Acacia leucopholia, Salvadora oleoides. Phoenix syslvestris, Holoptelia integrifolia as major tree species and Ziziphus nummularia, Euphorbia nivulia, Holarrhena antidysentrica, Cassia auriculata as major shrub species. The other species are Lepkidenia pyrotechnica, Cassia torn. Cassia occidentale and Ocimum americanum. The major grass species are Aristida hystrix, Eragrostis unioloides, Melanocenchris jacqueniontii, Andropogon pumihis etc. e) Anogeissus pendula forest The presence of nearly pure crop of Anogeissus pendula is the characteristic of this forest type. The trees are quite well stocked, about 6 meters high and centimetres in girth but branched from about meters above the ground. This 44

20 type of forests occur in Ajmer, Alwar, Sawai Madhopur (Ranthambore), Baran, Chittorgarh fort, Dungarpur, Banswara and Badnor division of Udaipur with associated species such as Boswellia serrata, Acacia catechu, Acacia rupestris, Albizzia odoratissima, Bahunia racemosa, Acacia leucopholia, Diospyros cordifolia etc. The Boswellia usually tends to occupy the ridge crests and Diospyros cordifolia is particularly found on the forest fringes. Acacia rupestris replaces Anogeissus in poorest soils. This association links both the northern and southern forms of dry deciduous forests with the thorn forest. It is apparently an edaphic climax because though it occurs on various geological formations and different type of soil, it has maintained itself and is also regenerating naturally under complete protection for over 100 years. It may also be noted that in these forests both Anogeissus pendula and Acacia catechu occur in fairly extensive and nearly pure stands as well as in intimate mixture and it is difficult to recognise any factor determining which of the two should predominate. f) Dry tropical riverain forest Dry tropical riverain forest is an irregular overwood of greater height than the climax dry deciduous forest. The trees are often larger in size forming patches and strips with varying amounts of smaller trees and shrubby undergrowth. The foliage is more or less evergreen in several of chief dominants. In Rajasthan these forests are present along the Mahi River in Banswara and Sabarmati River in Udaipur. The major flora includes Eugenia heyneana, Terminalia arjuna, Holoptelia integrifolia, Tamarix diocia, Vitex negundo, Typha angustifolia and grasses such as Cynodon dactylon, Cyperus spp., etc. On the higher ground the more xerophytic element of the typical flora of the region such as Ziziphus nummularia, Calotropis procera, Capparis decidua, Cassia auriculata, Tephrosiapurpurea, herbs like Sacrostemma parvifolia, Borreria hipsida and grasses such as Eragrostis tremula, Cenchrus spp., Apluda etc. 45

21 g) Mixed xeromorphic thorn forest Chapter 2: Study Area The plant communities growing on the rugged and scattered hills besides the Aravali in Jalore, Pali, Barmer, Jaipur and Sikar districts represents this vegetation type. The communities are largely dominated by thorny and spiny species, which include some evergreen non-thorny species as well.. Acacia Senegal community, which under protection attains density of 72 plants per ha and 100% efficiency largely dominate low hills and rocky areas of 150 to 350 mm of rainfall zone. The Anogeissus pendula - Acacia Senegal community occurs in mm rainfall zone whereas in mm zone Anogeissus pendula community is predominant with Acacia catechu as chief associate. The chief shrub associates in mm rainfall zone are Commifera wightii, Ziziphus nummularia, Grewia tenax, Euphorbia cauducifolia, Mimosa hamata, and Sericostemma acidum. The associated trees are short with crooked boles such as Salvadora oleoides and Maytenus emarginatus. The associates in mm rainfall zone are Wrightia tinctoria, Moringa cocanensis, Azadirachta indica, while in mm rainfall zone the main associates are Securinega leucopyrus, Dichrostachys cinerea, Grewia villosa etc. The major grasses and forb species are Cymbopogon spp., Aristida spp., Eleusine spp., Melanocnechrus jacquemontii, In digofer a spp., etc. i) Mixed xeromorphic woodland This formation is a mix of spiny species, non-spiny and evergreen species occurring on the flat older alluvial plains and lower piedmont plains with deposition of sandy loam or clay loam or clay soils underlain with a hard hanker pan. The major plant species encountered in the desert plains spreading throughout the Jaiselmer, Barmer and Bikaner districts are Salvadora oleoides, Prosopis cineraria, Ziziphus nummularia, capparis deciduas, and Acacia nilotica in different combinations. 46

22 The inclusion or exclusion of any one species, affect the association significantly, and therefore these may beregarded as phases or "Facies" of the climax community, largely indicating the extent of degradation reflected in the preponderance of Tephrosia purpurea, Crotolaria burhia and Indigoflora oblonifolia. The common shrub associates are Calotropis procera. Balanites aegyptiaca and Acacia jaquemontii. The forbs and grasses are Aerva persica, Tephrosia purpurea, Crotolaria burhia, Convolvulus microphyllus, Heliotropium subulatum, Cenchrus spp., Eleusine compressa, etc. j) Mixed xeromorphic riverain thorn forest The narrow belt of younger alluvium having deep sandy soils without a hard pan along the Jawai, the Sukri and the Luni rivers and their tributaries in the western rajsthan have good density of trees of Acacia nilotica, A. cupressiformis, Salvadora oleoides, S. persica, Tamarix auriculata, Tecomella undulata, Tamarindus indica, Albizzia lebbeck, Ailanthus excelsa, Ficus spp., Moringa oleifera and Ziziphus mauritiana. Acacia nilotica-prosopis cineraria community is predominated in irrigated fields along the river courses and represents the climatic climax of this region. On medium heavy soils S. oleoides and P. cineraria dominate, while at degraded sites Tamarix, Ziziphus, Acacia jacquemontii and grasses and sedges predominate. k) Lithophytic scrub desert Cushion-shaped pillow-form, multi-stemmed trees and shrubs on eroded rocky surfaces, gravely plains and piedmont plains with shallow soil deposition in desert districts of Rajasthan represent this type of vegetation. Capparis decidua-ziziphus nummularia is the most prevalent shrub community on these surfaces and stray plants of Acacia Senegal and Prosopis cineraria also occur along the deep tunnels. 47

23 Associated shrubs, under shrubs, forbs and grasses are: Leptadenia pyrotechnica, Crotolaria burhia, Sericostoma pauciflorum, Bonamia latifolia, Tribulus terrestris, Indigofera cordifolia, Dactyloctenium sindicum, Elusine compressa, Eragrostis spp., Aristida hirtigluma, etc. 1) Psammophytic scrub desert This formation has woody vegetation, predominantly shrubs, on Aeolian deposits viz. stabilised dunes, undulating hummocky older alluvial plains and interdunal hummocky plains with very deep loamy sands often calcareous. Typical psammophillous species present on these dunes and plains are Aerva persica, A. pseudotomentosa, Crotolaria burhia, Panicum turgidum, Cyperus laevigatus, Callogonium polygonoides, Clerodendron phlomoides, Cenchrus biflorus, Aristida funiculate, Citrullus colocynthis, Dipterygium glaucum and Haloxylon salicornicum. Sand dunes with moderate sand deposition support Callogonium polygonoides, Clerodendron phlomoides, panicum turgidum, Acacia jacquemontii, Acacia Senegal, Maytenus emarginatus, Calotropis procera, crotolaria burhia, Aerva pseudotomentosa, Sericostoma pauciflorum and Leptadenia pyrotechnica. Sprawling grasslands of Lasiurus sindicus cover substantial area in this low rainfall zone in the extreme west. m) Halophytic scrub desert In low-lying saline basins and depressional areas called ranns or playas succulent halophytic nanophanerophytes and chemophytes, generally of Chenopodiaceae, Zygophyllaceae, Aizoaceae and Portulacaceae grows which are categorized as halophytic desert scrub formation. 48

24 The major species are Suaeda fruticosa, Aeluropus lagopoides, Haloxylon recurvum, Salsola barysoma, Sporobolus marginatus, Sporobolus helvolus, Cyperus rotundas, Peganum harnmala, Elusine compressa, Desmostachya bipinnata, Zygophyllum simplex, Cressa cretica, Euphorbia granulata, Portulaca oleracea. Fagonia cretca, Trianthema portulacastrum, echinochola colonum, Chloris virgata, Scoenfelida gracilis, Dactyloctenium aegyptium and Dicanthium annulatum. 2.6 Fauna Rajasthan offers a rich variety of flora and fauna. Some of the finest national parks and sanctuaries are found here. The majestic predators, assured of protection, roam freely during daytime and can be seen at close encounter with tigers, black bucks, chinkara, the rare desert fox, the endangered caracal, the great Indian bustard, gavial, monitor lizard, wild boars, porcupine. Migratory birds like the common crane, ducks, coots, pelicans and the rare Siberian cranes, imperial sand grouse, falcons, buzzard's flocks to this state during the winter months. The state is enriched with three National Parks and over a dozen Sanctuaries. These are: a) Keoladeo Ghana National Park: The 29 kms national park is one of the finest bird sanctuaries in the world, inundated with 400 species of water birds. Exotic migratory birds from Afghanistan, Central Asia, and Tibet as well as Siberian cranes from Arctic, graylag geese from Siberia and bar headed geese from China. Colonies of cormorants, spoon bills, storks, egrets, herons, pelicans, ebis and grey herons can be spotted all over the park. b) Ranthambore National Park: The park is one of the finest tiger reserves in the country under the project tiger. The 392 sq. kms., park comprises of dry deciduous forests sprawling over undulating terrain of hills. One can spot sambhar, chital, wild boar, leopard, sloth bear, jackal, and hyena among others. The park is 49

25 enriched with its beautiful lakes, attracting large number of migratory and local birds. c) Sariska Tiger Reserve: This is another excellent tiger sanctuary in a huge and thickly wooded reserve cradled in the picturesque valley of the Aravali. The forest is 765 sq. kms. The forests of the reserve are noted for their population of rare breed of tigers, leopard, sambhar, nilgai, wild dog, and chinkara. d) Kumbhalgarh Sanctuary: The 586 sq. kms. sanctuary is sporting a rich variety of wild life like the panther, sloth bear wild boar, four horned antelope and scientifically bred crocodiles in the lake are the major attractions. The sanctuary is also known for flamingos, cormorants, spoonbills and egrets usually seen in the winter. e) Darrah Sanctuary: Laying along the southeastern border of Kota adjacent to the mountain range this sanctuary covers an area of 266 sq. kms. This hilly Sanctuary with its thick forests is worth a visit. The wildlife variety includes panther, wolf, sloth bear, chinkara and leopard. f) Desert National Park: The park is dominated by rolling sand dunes and scrub covered hills. It is colossal park sprawling on 3162 sq. kms. The prominent fauna of the park includes black buck, chinkara, desert fox and the great India bustard, comprising sand fish, sparrows, imperial sand grouse, falcons and eagles migrate here during the winter. g) Jaisamand Sanctuary: The sanctuary allows a close encounter with the rich wildlife in their natural habitat. It is the wild home of panther, sloth bear, mongoose, chital, chinkara, wild boar and various species of migratory birds. h) Mount Abu Sanctuary: Located at the highest peak (1722 mts above the sea level) of Aravali, the Guru Shikhar lies in this 289 sq kms sanctuary. This sanctury 50

26 provides shelter to the wild boar, sambhar and leopard. The gray jungle fowl can also be spotted here. Besides, a number of flowering trees enhance the beauty of this place. 2.7 Socio-economic Profile Greater multiplicities of people are found in Rajasthan where their roles have evolved according to their assigned social tasks, setting up a tier of castes according to functional lines. In a cultural zone, it is not unusual that the people's trademark became their task at hand, carried forward by each generation to a degree of specialization that is so fine that the communities have sub-groups who especially create pottery, or who are entertainers, or whose chosen role is as painters, carpenters, dancers, or priests. These are jobs assigned not on individual merits but on the basis of one's caste. The system of learning has been within familial groups, so that a small child is born into a trade that he will learn from his childhood while observing his elders. These groups can be divided horizontally or vertically and range from the practical to those dealing in leisure, from serving needs to recording family histories. A genealogical study of Rajasthan would, therefore, include the warriors, the priests, the businessmen, the support communities, the tribals and the nomads as the major groups inhabiting the region. The Rajputs form the warrior aristocracy of the state and though their population, in relation to the original inhabitants of the desert state may have been far less, it was they who went on to become its elite through their acts of daring and elaborate rituals of kinship and inter-linked camaraderie. The Brahmins served in the royal courts and worked in departments of administration, though their main task was to administer the souls of the people they served. They were priests in the temples and performed the complex rituals of prayers to mollify the gods. Over a period of time, 51

27 a greater influence in court came to be not the Brahmin priests, but members of the business community. Even though they formed a miniscule percent of the population, they controlled the economy to a large extent. In essence, there are two mercantile communities in Rajasthan, the Marwaris and the Jains. The Marwaris arose from the Shekhawati region and served in the courts of different princely states. They came to be referred to as Marwaris when they journeyed along with the armies of Marwar (Jodhpur) to the eastern extremities of the country. Most of the major business and industrialist families, till very recently, have been Marwaris, and they still dominate business in the country. While the association of Rajasthan is always with its warriors, it cannot be denied that the nature of society has also been largely agro-pastoral and it is the Jats who are best associated with agro-pastoral activities because of their skill in turning even arid lands into fertile fields. While Jats are the major agro-pastoral communities in eastern and northeastern region Bishnois are the major agropastoral community of western region, famous for their conservationist role and protection of forests and wildlife. Even now, no tree may be cut on Bishnoi land, even for firewood; while roaming herds of deer seek shelter in their fields because they have come to know that even poachers will not venture into these lands in search of game. Principally, the Muslims came to Rajasthan as invaders and therefore found little to entice them to stay here. If the Rajputs, the Brahmins and the Marwaris and Jains formed the social elite, the role of the service castes is no less significant. At one end of the spectrum they included those whose task it was to provide: therefore, there are kumhars who are potters, khatis who are carpenters, sonars who are gold and silversmiths, lohars who are ironsmiths, bhats who keeps family records, chhipas who printed cloth while the rangrezs dyed them; there are groups that worked with leather, others that weave the cloth people needed to wear and others such as malis who are experts in growing vegetables. There are the bhopas and the dholis, the charans and the 52

28 puppeteers, whose job is to entertain, to act as drumbeaters and to keep alive the tradition of oral history with exaggeration of feats for its patrons. Communities such as the Langas and Manganiyars, now famous around the world for their performances, are only called upon to entertain. The bhopas, who recite legends associated with the folk hero Pabuji, are wandering minstrels who traveled to villages and whose visits in times of famines and other misfortunes were solicited, to recite and perform their tales of sacrifice for the protection of community life. The tribals are believed to be the original inhabitants of the hilly tracts of the desert. They have also earned themselves a great name for their skills at both warfare and the zest with which they celebrate their festivals and conduct their lives. The Minas are among the best known of the so-called tribes, who once ruled in the tracts that the Kachchwahas won through betrayal, to create Amber. The Bhils, who lived in the hilly tracts around Chittaurgarh, Banswara and Dungarpur, are even now primitive and ridden with poverty. Their way of life continues to be very colourful, but it is also an anachronism, since it dates back by several centuries. The Bhils have unfortunately not been able to make a life for themselves in the present times. Other tribals include the Sahariyas, people of the forest who once constituted the region's elite but have since diminished to abysmal levels of poverty and the Gerasiyas, who are somewhat better off, possibly the result of their song and dance, which has provided them a means of livelihood. For some communities in Rajasthan, nomadic existence has been a way of life. These people travel in large groups, often on a cyclical, seasonal basis, as they move around providing their particular services for people in settled communities. The most visible of the nomads are the Gadoliya Lohars, literally the blacksmiths who travel in their carts. The Banjaras, on the other hand, were nomadic caravan runners who traveled with balaads or oxen-laden caravan and who continued traveling wherever their caravans were in demand. 53

29 The Rabaris are still nomadic, an equally colourful sub-group that still travels over the desert in search of pastures for its flocks of sheep and camels. They travel across Gujarat, Rajasthan and Madhya Pradesh, colourfully dressed, with only the road to call their home. Other nomadic sub-groups include the Nayaks who are entertainers, Kanjars, Sansis, Nats and the Kalbeliyas, the last a group of snake charmers whose mesmeric dances have made them popular among world audiences and put an end to their nomadic way of life when they would have to dance on the roadsides to earn a living. 2.8 Problem identification The study area falls within a region, which receives less than a half-inch (only onecm) of rain. The forest area in Thar Desert is scanty with poor growth of vegetation. While the productivity is extremely low, the demand for fuel and fodder is very high. Consequently there is over-exploitation of vegetation cover accentuating the pace of desertification. The semi-arid lands have become degraded to the point where their original biotic functions have been damaged, with subsequent reclamation being costly or in some cases impossible. The plants and animals of this region find refuge in 11 protected areas that cover almost one-fifth of the ecoregion. Two reserves protect more than 1,930 square miles (5,000 square kilometers); one protects more than 7,722 square miles (20,000 square kilometers) (Anon., 2001). Although the Thar Desert may seem inhospitable to humans, it is actually the most densely populated desert in the world. Many of the people who live here graze sheep and goats, which can reduce soil fertility and harm native plants. The continually increasing population intensifies pressure on marginal lands and subverts efforts to introduce sustainable agricultural practices, leading to environmental problems such as soil erosion and deforestation. 54

30 And as farmers move to the area now that irrigation water is available from Indira Gandhi Canal, conservationists are looking for ways to protect the desert vegetation and help people have a better quality of life. Monitoring the vegetation condition in these regions have become imperative in view of the role these regions play in determining substantive dimensions of global climate changes. Quantitative relationship between the data products and effective surface parameters at varying scales helps in understanding and monitoring vegetation degradation in these regions at regional to global scales and provide a valuable insight about the transformations occurring at the land surface and its overall impact at local and regional scale. The surface parameter characterisation in these regions will not only give the condition of vegetation amount and its variability with seasonal climatic variations, but also provide a better understanding of the interactions between the vegetation and the atmosphere. 55