Grasslands define as terrestrial ecosystems dominated by herbaceous. and shrub vegetation and maintained by fire, grazing, clipping, draught

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1 1.1 INTRODUCTION Grasslands define as terrestrial ecosystems dominated by herbaceous and shrub vegetation and maintained by fire, grazing, clipping, draught and or freezing temperatures. The spatial extent of grasslands and modifications have altered their extent, structure, and composition over time. Modifications include human induced changes such as cultivation, urbanization, desertification, fire, livestock grazing, fragmentation, and introduction of invasive species. Natural grasslands have been defined as a plant community in which the dominant species are perennial grasses, there are few or no shrubs and trees are absent (Moore, 1964). The grasses are outstanding in their ability to adopt themselves to diverse ecological conditions. Temperate grasslands can be considered as transitional ecosystems, which with more moisture would become forested, or with less would turn to desert (Henwood, 1998). Grasslands respond to both temperature and moisture. Grasslands and other grazing resources occupy a very important position in the hill agriculture and the grassland utilization is an important component of the hill farming system. The herbage utilized during grazing is the largest fodder resource followed by crop residues, tree leaves, concentrates and cultivated fodder. Besides grazing, the grasslands are also used for harvesting hay, which is essential for maintaining the livestock during lean periods. The standing biomass of grass species is harvested during October November and conserved for use during winter. Some of the farmers let the biomass stand in their grasslands and harvest it on day-to-day requirements basis. The local people manage these grasslands by variety of ways such as fire, 1

2 clipping, and protection from grazing, or controlled grazing. There is no use of fertilizer in the management of the grasslands of the area. Intensively managed grasslands are mostly man made, as apposed to less intensively managed rangelands many of which are modified natural grassland. Most of the managed grasslands were created by the removal of natural forest, this has occurred in temperate Mediterranean and tropical regions (Moore, 1964; Snaydon 1981). Without grazing, cutting or fire these manmade grasslands would revert to forest- that is they are plagioclimaxes (Davies, 1959; Levy, 1970). As a result, man-made grasslands are ecologically unstable, botanical composition changes rapidly particularly in response to grazing or cutting management (Jones, 1933; Broughan, 1960). Grasslands are utilized both by grazing and cutting. Cut herbage is usually conserved and used to supplement animals during periods when there is insufficient available pasture though it is sometimes fed fresh. The main effect of grazing animals on the productivity and botanical composition of pasture is through defoliation though they also have an effect through treading, nutrient returns and seed dispersal (Donald, 1941 Sears, 1956, Watkin and Clements, 1978, Curel, 1982). Grasslands are extensively important from man s viewpoint. They provide natural pasturage for grazing animals. The principal agricultural food plants have been evolved by artificial selection from these grasslands. The grasses also play a vital role in cushioning the impact of lashing rain by providing a most effective cover for the soil, in reducing the runoff and thereby minimizing the disastrous floods and soil erosion. Tewari (1982) observed that in hilly region, about 60% of the fodder requirement of animals are met out from pasturelands and forests alone. 2

3 Grasslands as highly dynamic ecosystems provide goods and services to support flora, fauna, and human populations worldwide. Grasslands have been goldmines of plants used for food. Many of our food grainswheat, corn, rice, rye, oat, millet, and sorghum- have originated in grasslands; many types of grassland remain the primary source of genetic resources for improving our crops and for increasing the number of pharmaceuticals. Grasslands produces forage for domestic livestock, which in turn support human livelihoods with meat, milk, wool, and leather products. Grasslands provide habitat for breeding, migrating, and wintering birds, ideal conditions for many soil fauna and rangelands for wild herbivores. Grasslands vegetation above and belowground as well as the soil itself, serves as large storehouses for carbon, helping to limit global warming Grasslands are extremely important as pasture for grazing livestock and it is of increasing importance to adopt an ecosystem approach while studying them (Moule, 1964; Naveh and Ron 1966). As Tansley (1946) has pointed out, anything like a complete study of the ecology of a plant community necessarily includes a study of the animals living in or feeding upon it. When we eliminate biotic factors such as denudation, disturbances, grazing, firing etc, we can estimate relationship of grasslands to past climate. A phytosociological method may help in the analysis of vegetation climate relationships (Suganuma, 1966). Grazing animals affect plant communities in several interrelated ways (Balph and Malechek, 1985), including plant defoliation, nutrient removal and redistribution through excreta and mechanical impacts on soil and plant materials through trampling. However, grazing in most natural ecosystems is as much a part of the systems as is a need for forage by animals. Removal of grazing in such ecosystems often results in the development of plant communities, 3

4 greatly different from that which originally developed under grazing (Heady, 1984). India lies in South Asia, the grasslands in southern Asia are of often secondary in nature, having originated from forest clearing and burning by man rather than in response to soil and climate (Sanford and Wangeri, 1985). Grasslands also occupy canopy gaps in open forests and form distinct association (Champion and Seth, 1968). Grasslands are related to agroecosystems by providing a rich gene pool and including species, which serve a collateral host for many plant diseases, insects, and nematodes. Also, most of the agriculture depends on animal power, which derives energy from the grasslands by grazing or by stall-feeding of dried and cured herbage. The climates of the Indian subcontinent except for the alpine region of the Himalaya, above timberline, are suited to the development of forests and deserts; the major portion of the grasslands is of recent origin (Bor, 1960). Large- scale destruction of natural forests especially over the last 150 years has resulted in their replacement by grasslands communities. Several workers have described the parallelism and association of grasslands and forest types of India (Yadava and Singh, 1977; Saxena and Singh, 1980). The Himalaya are among the youngest mountains in the world, which are active as well as fragile, and are facing threat from mankind in the name of development. Because of increased anthropogenic activities, as a result of population and change in land use practices, the natural landscape has been modified and resulting in fragmentation of forests with poor species composition. The rate of environmental degradation in Himalayas is increasing day by day, as cultivation is pushing into the 4

5 forests. Growing population both of humans and livestock is creating pressure upon the limited resources. In the Indian Himalayan region most live stock species are raised under mixed cropping systems. In the central and eastern Himalayas most common cattle are cows (47.5%), followed by goats (15.8%), buffaloes (12.3%) and sheep (10.4%) (Rao and Saxena, 1994). The land holdings are small and therefore livestock supplements the family income. The average number of livestock per household in the low hills is 11 animals, cattle accounting for 55%, sheep and goats for 36% and the rest fall under remaining 11% (Sharma, 2004). An analysis of temporal changes in livestock population and composition between in the Central Himalayas (Uttarakhand) and between in the Western Himalayas (Himachal) shows that in areas where the cattle population has declined, the buffalos or stalfed jersey s population increased significantly due to the engagement of local people in horticultural practices. The crop grown or grasslands are converted into the orchards. People of the area have reduced the number of surplus cattle and preferred high quality hybrid buffalo or jerseys. The sheep population has also declined drastically (Tulachan, 1998). Mid Himalayan pastures contain upto 95% of grass component, while the alpine pastures have 41% of grasses (Melkaniya and Tondon, 1988). The legumes contribute only 1.37% of the entire floristic composition. The biomass production of these grasslands is declining significantly due to the invasion of noxious and poisonous weeds. These grasslands are declining due to various developmental activities in the temperate regions (Misri, 1995). Particularly in the temperate region of Himachal Pradesh, shrinking 5

6 of grassland is resulted due to the illegal encroachment of the Government land by the local people. The mountainous state of Himachal Pradesh is known for its vast natural wealth, including forest, alpine meadows, rivers and valleys endowed with a rich array of life forms. The relief features of the Himachal Pradesh comprise of massive peaks, hills, valleys and spurs. The higher Himalayan Mountains here exert a vital impact on the life and land. The physiography of the area is complex, comprising hills and mountains, major part of the state inaccessible, snow covered and infested with thick forests. An area of about 25.1% of the total geographical area i.e., 565,019 km 2 is under forests. The state is known for its forests and their floral and faunal diversity. Among the 45,000 species of plants found in the country as many as 3295 species (7.3%) are reported in the state (Chandrashekhar et al.2003). About 30% of the worlds grasslands occur in the temperate region, and temperate grasslands maintain approximately 35% of the world ruminant livestock (Reid and Jung 1982), mainly sheep, beef cattle and dairy cattle. In the temperate regions livestock is reared under three distinct systems i. e., sedentary, semi- migratory and migratory, the sedentary systems is practiced by the farmers living in or around the subalpine pastures. The animals are let loose for open grazing from March to November and if does not snow, the grazing period is extended. Under semi-migratory system, the livestock reared below the sub-alpine areas is taken to sub- alpine and alpine areas for grazing during summer (April- Oct,) and is brought back during winter when the feeding restricts to crop residue. Under migratory systems of live stock rearing, the nomadic tribes like Gujjars, Bakarwals, Gaddis, Bhotias etc, practice a continuous 6

7 transhumance along with their livestock. As soon as the snow melts in these pastures, large herds of sheep, goat and cattle are taken there for grazing from March to October when it starts getting colder and the downward movement starts. Temperate areas are situated between m altitudes and even these exhibits a remarkable diversity. In Himachal and Uttarakhand Himalaya, the valleys are very narrow and terraced farming is the only alternative. Most of the temperate areas experience a hostile and prolonged winter offering only a short summer of 4-5 months during which the entire agricultural activities could be carried out. The landholdings are small and the biomass availability is very low. These constraints have resulting in the adoption of animal husbandry as a secondary source of income at lower altitudes and the primary occupation at comparatively higher altitudes. The temperate Himalayan regions are spread over the states of Jammu and Kashmir, Himachal Pradesh and Uttarakhand. The entire temperate zone experience mild summers and cold winters. The temperate areas of Himachal Pradesh receive the annual monsoon. Most of the sub-alpine and alpine pastures are under snow from November- December to March- April Silvi-pastoral systems in the form of natural grasslands and pastures with or without trees, as a consequence of ecological succession are common in the region. Out of the total geographic area of Himachal Pradesh, an area of 24,730 km 2 forms the permanent pastures and other grazing lands of which 16, km 2 lie above the tree growth limit representing the alpine pastures, barren and uncultivable waste. The former constitutes % and the latter % of the total geographical area of H.P (Dewan, 1987). These pastures and grazing lands are locally called as Thach, Ghasin, and Jubbad. Thach is the alpine pasture without woody 7

8 vegetation, Ghasin/ Panwis, is natural or manmade community land or forest, lands under the right of local people protected for their fodder requirements, Jubbad, constitute the areas with flat ridges which resulted due to continuous grazing by heavy footed animals, where herbaceous plants alter their habit and life forms, become prostrate, cushioned and creeper. This vast natural resource has given birth to nomadic profession of grazing cattle in a sequential manner i. e. in low hills during winter and high hills or alpine pastures during summers. Ghasnis or community grasslands near the villages, which once sustained cattle grazing, are also highly eroded today, bearing only shrubs of euphorbias or other xerophytic species. Due to poor irrigation facilities and the climatic limitations only 0.8% (8,000 ha.) of the total cultivated area is utilized for forage crop production (Sood et al., 1995). The poors, who often depend directly on ecosystems for their livelihoods, suffer most when ecosystems are degraded. A critical step in managing these ecosystems is to take stock of their extent, their condition, and their capacity to continue to provide what we need. Ecosystems provide us with wealth of good and services, including, food, building and clothing materials medicines, climate regulation, water purification, nutrient cycling recreation opportunities and amenity value. 1.2 AIMS AND OBJECTIVES Our natural resources are being depleted constantly due to mounting population pressure and dependence of man on his surroundings. The unscientific exploitation of these resources has led to extinction of many valuable species. For a sustainable development of these resources, proper understanding of the system is a necessary prerequisite. Simultaneously, 8

9 management practices are essential not only to achieve the goal of sustainable but also to conserve our valuable natural resources. In the proposed study, an attempt to work out the suitable management practices in Himachal Pradesh temperate grasslands is carried out. Fire, clipping and protection will be compared vis-à-vis grazing to ascertain the best method for conservation, sustainable development and balanced ecosystem Objectives: 1. To collect the meteorological data of study area. 2. To study the physio-chemical characteristics of the soil in varying habitats. 3. The phytosociological studies of various sites along with their ecological diversity. 4. To study the ordination of the temperate grassland plant communities. 5. To study the biomass and productivity of the various sites. 9