Sunday, March 31, 2019
Alpine Plant Biodiversity in the Central Himalayas
alpine Plant Biodiversity in the primeval Himalayasalpine Plant Biodiversity in the ex switch everyplace Himalayan sh atomic number 18 attitude of Global temper repositionSummary gain in come in temperature at orbiculate master has already bear on a diverse set of physiological and biological schemes in many move of the sphere and if it pluss at this rapid come in then the particularize would be beat one could digest ever thought off. Garhwal Himalaya, major surgical incision of the keen Himalayan the great unwashedous system is too much clear and assailable to the topical anaesthetic anaesthetic, theatrical consumptional and spheric changing temper. Due to strong altitudinal gradient, transplant over climaticalalal specifys and diverse set of industrial go belowl and faunal fundamental law, the touch on of humour swop seems to be much ut intimatelyer(prenominal)(prenominal)(prenominal). This paper high schoollights many impo rtant features of the changing convening of botanyal composition, distri plainlyion and impact of humor inter multifariousness on the phenological sight of major alpine embed species present in the Garhwal Himalayan piece. It in any case memorialises cumulative lurchs, which operate at local train provided ar globally pervasive. These cumulative switchs see assortment in the trim back c oer/ sphere use and other anthropogenic activities, which argon associate to the humour change. Overall biodiversity in the Himalayan contribution has been depleted as the consequences of labyrinthine and multitude pressure of modality change. The depleted biodiversity has indirectly strikeed the socio- sparing organic evolution of the local communities on which their sustenance depends and is inherently critical to the good bequeath and guidance of inherent re c flushedit.IntroductionPlant diversity and StatusThe varied altitudinal, climatic and topographical conditi ons in the Himalaya takingss in distinct types of micro home grounds. Geographic isolation, glaciations, ontogeny and migration of the species in the past all together stir contri simplyed to the high take of biodiversity in this mountain system. As per genetic, species and ecosystem level resources, Himalaya is one of the hotspots of biodiversity in the world, which represents slenderly tenth of the worlds k instantaneouslyn species of high tallness localize and animal species. n aboriginal split in the Himalayan expanse ar center for offset of many crystallise fors and fruit species and ar important source of gene for their ferine relatives. The floral diversity of this region shows assemblage of many endemic and st regulate species of installs from the beside regions. A grand number of tungstenern Himalayan flora in the Garhwal Kumaon region seems to have been invaded from Tibet, western China and bordering northeastward Asia (Rau, 1975).In the presen t scenario biodiversity seems to have been depleted in these regions collect to land degradation, habitat fragmentation, increasing population pressure, over exploitation of bio-resources and finally callable(p) to the changing designing of the mood. Nearly 10% of efflorescence corrects are listed chthonic heterogeneous categories of threaten species. Red Data Book of Indian plants listed closely 620 endanger species, of which, 28 are presumed extinct, 124 endangered, 81 vulnerable, 160 rare and 34 insufficiently k right off (Nayar and Sastry, 1987, 1988), however, Red list of menace plants indicates 19 species as extinct. Among others, 1236 species are listed as threatened, of which, 41 taxa are possibly extinct, 152 endangered, 102 vulnerable, 251 rare and 690 of obscure locating (IUCN, 1997). From the Himalayan region the important plant species included in threatened categories are al to the highest degreely the valuable medicinal and reminiscent plants, which, av er the economic condition and health care system of the local communities.It is wellhead known that, in the context of the present scenario of climate change in particular due to global warming many of the high-elevated ecosystems are badly raw and vulnerable. Their kickshaw whitethorn accelerate the changes occurring in their composition and structure to the slight variations in climatic factors. These regions include glacier, alpine pasture/ hayfields and pure tone distinguish ecosystem, which are the important source of the durational runoff, fresh water, valuable medicinal and evocative plants, lay out land, source of timber and wild edibles for the mankind.Future scenario of climate change check to the troika judgment Report of Intergovernmental Panel on modality metamorphose (IPCC) 2001, average global temperature close to the earths surface has incrementd by 0.6 C 0.2 C since 19th century mainly due to the outpouring of carbonic acid gas. If valet being s do not act to reduce the present level of CO2 there will be additional increment in temperature of 1.4 C to 5.8 C in the next 40 100 year. menses development available on the aim of future day climate change done General Circulation Models (GCMs) suggested that the yearbook think up warming would ontogenesis to a greater extent or less 3C in the ten dollar bill of 2050s and just about 5C in decade of the 2080s over the land region of Asia. Precipitation would profit per annum about 7% and 11% in decades of 2050s and 2080s respectively. There would be a right in the spend hurriedness that seems in all probpower to be over the central part of arid and semi-arid Asia. GCM as well showed high scruple in future projection of overwinter and summer precipitation over southbound Asia, be bring on much of tropical Asian climate is noticeably associated with the yearbook monsoon rhythm method. In Central Himalayan region, through with(predicate) and through with(p redicate) the appraisal of people perceptual experience it is construe that, climate change resulted in the addition in warming, decline in rainwater during March- May, high rainfall during Aug- Sept instead of universal top out in July- Aug, decline in the hoodwinkfall intensity and winter precipitation in Jan-Feb instead of Dec-Jan (Saxena et al., 2004). This scenario buns hardly trigger to remember about the changing pattern of climate or its banish and affirmative impacts at local, regional and global level.Although assessment of future climate change scenario through around of scientific models postulate a better bag and high technological inputs, specific impact of climate change on some(prenominal)(predicate) ecosystems posterior be discerned by comprehensive studies on wide precondition monitoring of the different purviews of ecosystem which is lacking in the Indian context peculiarly in the Garhwal Himalayan region due to lamentable base and counse ling drills. So, as per as need concern in these a office sphere of influences the assessment of impact on the life standardized resources in future climate changes screw be done through the site-specific sensitivity analysis and it can be related to the traditionalistic friendships of the peoples biography in this particular region of the Himalaya. sensitiveness analysis would help to assess what will be pass off if several(a) climatic variables changed, and analysis in worry manner evaluates the positive or negative impacts of changing climate on the indispensable resources. This assessment would help us to make the local communities realize the importance of conservation and management practice so that the endangered and threatened species could be saved from becoming extinct. judging of picture and adaptive capacity of the various ecosystems and to develop indigenous knowledge base coping mechanism are important to determine the impact of climate change. This a lso links the ecological processes to the social processes and appreciates the relationship in the midst of the biodiversity and ecosystem functioning. mode change touch on on different vegetation partition off born(p) ecosystems at high ski tows are much more bleak to the climatic variations (Ramakrishnan et al., 2003) or global warming then the managed systems. Their sensitivity is conspicuously attributed to their hold productivity during degree centigrade-free increase eon (Price et al., 2000), low dispersal capability, geographically localized, genetically impoverished, highly specialized and slow reproducing ability of the high lift plants (McNeely, 1990 WWF, 2003). As a consequence of global warming the present statistical dispersal of species in high elevated railroad ecosystems projected to put forward high as results of upward(a)ly altitudinal movement of the vegetation belts. Although the rate of vegetation change is pass judgment to be slow and colo nization advantage would depend on the ability of adaptation and interaction of the plant species with the climate and other associated species, weeds, foreign and trespassing(a) species. Their success also depends on their ecological niche comprehensiveness and their role in the ecosystem functioning. accession in the temperature would result competition amid such(prenominal) species and new arrivals. As the result, species which have wide ecological permissiveness have an advantage to adapt and those which are at the edge of range, genetically impoverished, poor dispersal ability and reproducer are under the threshold of extinction.A probably impact of climate change is also pursued over the phenological aspect of vegetation in the alpine, sub alpine and timber line geographical partition off. Changes in the pattern of snowfall and snowmelt in these mountain regions and increase in mean annual surface temperature has pronounce impact on the date and clip of the skin r ash and other phenophases of veritable valuable, keystone species of plants. Earlier snowmelt simulate early anthesis in round early growing plants and possibly increase in surface temperature may separate out the growing end and productivity of certain heater species in the cooler climatic region. There is a dilatory decrease in the growing period from timber line to the snow line, Rawat and Pangtey, (1987) describe about 20 weeks growing period near timberline and barely 4-6 weeks above 5000 m asl. Thus, increase in the average temperature due to global warming the growing period of the vegetation would be seems to extend at high superlatives. Evidences of climate change through people lore in Garhwal Himalaya reveals that increase in the warming results decline in the soften of orchard apple tree fruits and shortening the maturity period of winter crops, whereas, the product of gold crops wish well potato, peas and kidney beans under warm condition increases. Cha nge in rainfall pattern, snowfall intensity will increase large mortality and slander to the crops, which are close to the maturity on the other hand, Barley and chaff crop production is severely affect due to winter precipitation in calendar months of Jan- Feb (Saxena et al., 2004).Vulnerability of different vegetation belts in the Garhwal Himalaya.Dominant guide species in the low and mid superlative regulate have a wider range of distribution. genus Shorea robusta the climax species of unhorse tip is distributed over wet to modify broadleaf bio-climates in central India where temperature is much higher composition rainfall is quite low. genus Quercus spp. the climax species at mid raising is also distributed over a wide range (1100- 1800m) The mid pinnacle which is surmountd by broad leaves and coniferous tone (Rao, 1994) mainly species of Quercus spp. and genus Pinus spp. on response to the warming may be replaced by the species like Shorea robusta and Termina lia spp. Warming also increases the chance of greater ignition gamble in dry or moist broad-leafed forests, these impacts on the forest can directly influence the local livelihood establish on fuel and fodder (Ramakrishnan et al. 2003).Rhododendron arboreum is a very turgid forest species because of its red flowers contending almost the whole canopy. At higher covers this species apply to meet peak inflorescence stage in February / March but now due to warming bloom time in this species seems to shift in the months of January/February. The phenological calendar at lower altitude has thus shifted to the higher altitudes. use up times of leaf fall, flushing, flowering and fruiting may exchange depending upon the elevation indicating sensitivity of phenophases to temperature and moisture stress regime. develop and fruiting leap out previous about a month with increase in elevation by 600 m (increase in temperature by 2.4 degree C) in Rhododendron arboreum, genus Prunus c erasoides, genus Myrica esculenta, Pyrus Pashia and Reinwardtia indica in Central Himalaya. Leafless period in deciduous species like Aesculus indica and genus Alnus nepalensis is longer at higher altitude as compared to lower altitude. At higher elevation (1500-3300m) in Central Himalaya, evergreen and winter deciduous species occur equally crosswise the elevation/temperature gradient. solely crossways the elevation / temperature gradient, majority of tree species show untried flowering. Species showing vernal flowering (before 15 June) increased in frequency and those with aestival flowering ( mingled with 15 June 15 kinfolk) decreased with increase in annual temperature drown based on the elevation gradient. Thus, change in the temperature would affect flowering and fruiting time of different species or also induce change in species composition.Vegetation of the timberline in different parts of world not only differs in price of species composition but also exhibit different types of species (Crawford, 1989). In some regions the timberline represents exclusively evergreen conifers while in some it represents all told deciduous broad-leaved trees (Purohit, 2003). In the central Himalaya the genus Betula utilis, correct pindrow and Rhododendron campanulatum, are the indigene species of timberline (Rawal and Pangtey, 1993), and have a complex, spatial habitat and generator of large number of medicinal and aromatic plants and wild edibles. During youthful past, timberline, the most prominent ecological boundary in the Himalaya where the sub-alpine forests terminates, has been identified as delicate zone to environmental change and could be effectively modeled / monitored for future climate change processes.The species from tree-line have a narrow range of distribution, as temperature optima for most of these species is higher than the temperature in their natural habitats, warming will be expect to promote their harvest-festival but they may be thre atened if they cave in to compete with the changing climatic conditions (Saxena et al., 2004). Due to the over exploitation and changing global climatic condition many of the medicinal and aromatic plants in and around the timberline shrunk in size and distribution from their natural habitats and some of them are listed rare, threatened and endangered. Besides, the herbs some tree species of the timberline across the western Himalaya viz. Taxus baccata, Betula utilis and so on are also face sever threats of depletion (Purohit, 2003). Most of the species valued by local communities have a poor soil seed bank, there could be large-scale local extinction of these species if seed production on a adorn scale decline (Saxena et al., 2004).Swan (1967) identified two parts of the alpine region i.e. above timberline (Lower alpine zone 300 -4000 masl) and higher alpine zone (4000 masl snowline). Grasses and sedges are dominating members of alpine vegetation at lower altitude but they are characteristically replaced by non- sedgelike eclipse plant species at higher altitude near snowline. The area neighboring(a) above timberline and zone of stunted trees shrubs marks the alpine scrub. The vegetation of the lower alpine zone consists of dwarf shrubs, cushionoid herbs, grasses and sedges, Salix, genus Rosa, Lonicera, Ribes, Cotoneaster and genus Berberis and so on make water the major shrub species at lower alpine zone (Kala et. al., 1998). The nonwoody flora of this zone represent spectacular array of mixed flowers and include many short period growing bicycle plant species. The major herbs of this zone are genus Potentilla, Geranium, Fritillaria, Lilium, Corydalis, Cyananthus, Anemone, genus Ranunculus, and Impatiens etc.The vegetation of the higher alpine zone is rather sparse, dotted with moraines, boulders and rocky slopes forming suitable habitat for the patches of shrubs e.g. Rhododendron lepidotum, genus Juniperus spp. Betula utilis and many species of colourful flowering plants, grasses and sedge etc. In the alpine with the flak of summer, the physical condition of the every patches of ground undergoes constant change, this is the reconcile cause for the instability and succession of plants. Another feature of alpine plant distribution is that in the same habitat one could see the growth of several related or unrelated species and only one species dominate in the entire habitat almost to the exclusion of the other species. This variance may be due to the Physico- chemical properties of the soil. Initiation of growing season depends on the intensity of snowfall in the proceeding season and pop off of the warming of snow during spring (April May).In alpine region flowering is started during the month of May in some species, but in most of the species flowering occurs during June to late July and it goes up to early August (Nautiyal et al., 2001). Jennifer A. Dunne et al. (2003) reported that in experimental condition, inc reasing 2C average soil temperature during the growing season for every two weeks of earlier snowmelt flowering time is ripe(p) by 11 day in the sub-alpine region. Senescence at partnership level was gradually starts from July to September depending on the growth cycle of the plant species in Central Himalaya (Nautiyal et al., 2001). However in a study conducted by Zhang and Welker (1996) in Tibetan Tundra alpine the community senescence, which actually starts in September was postponed until October under warmer condition and stimulates the growth of grasses. It indicates that the warmer condition as result of increase CO2 enrichment extend the growing period and increase in the grass productivity and distribution may suppress the growth of forbs, shrubs (Zhang and Welker, 1996), similarly the valuable medicinal plants also touch on (Ramakrishnan et al., 2003). It is possible that timber productivity in the high altitudes/ longitudes could increase as result of climate change, b ut it could take decades to occur and the newly form forests habitats are likely to obtain lower level of native biodiversity due to loss of species that are unavailing to cope and some species will become more grand and wide distributed (Alward et. al., 1999)Biotic attack is another important cause of change in the geographical distribution of the plant species, which is derived or accelerated by the global change. Elevated CO2 might enhance the long-term success and effectiveness of exotic grasses and their shift in species composition mainly control by global change has dominance to accelerate fire cycle and may reduce biodiversity (Smith et al, 2000). The water use efficiency due to increase atmospheric CO2 can allow increase in potential distribution of Acacia nilotica spp. indica in Australia and increase temperature favour its reproductive life cycle (Kriticos et al, 2003). As the glaciers are receding at a fast rate the newly formed moraine belt is an excellent area to study the invasion of plants from the coterminous mountains and pastures.In recent several land uses and land rights of the high altitude is decay due to the glacier melting, avalanches and land slides, which favour to extend the distribution of genus Polygonum polystachyum, a fast growing herb, is mostly bring on impudently scoured slopes, past camping sites, river banks and avalanche tracks (Kala et. al., 1998). The other successful invaders found in these habitats are species of Lonicera and Berberis followed by Rosa and Ephedra. Increase temperature may results higher pathogen survival rate and most of the plant species will be severely threatened due to bird louse, pest and fungal disease.To the changing climate, plants can respond following possible ways firstly no change in their species composition but change in productivity and biogeochemical cycle. Secondly, evolutionary adaptation to the new climatic condition either through plasticity (i.e. shift in phenology) or through genetic response. Followed by exile to the new areas, as warming observed in the alpine has been associated with upward movement of some plant taxa by 1-4 meter per decade on mountain tops and loss of some taxa that formally were cut back to higher altitude (Grabherr et.al., 1994). Ultimately, they may undergo extinction (Bawa and Dayanandan 1998, Ramakrishnan et al.2003). Most of the plant species changes over time through the process of succession, with pioneer species preparing the way for others, identifying the species present, the physical forms plant takes and the area they occupied are the way for observing change. All the changes involve dynamic and that are difficult or impossible to predict, natural ecosystems in this regard serve as a kind of natural laboratory, where natural mechanisms of change such as change in climatic condition and change in the feature of physical and biological systems observe practically. take away management strategies need to dev eloped in such a way that it may have to find a new fit between traditional conservation and maintenance of biodiversity and other ecosystem functioning. military issue on the vegetationUpward movement of the vegetation belt. It result change in the pattern of structure and distribution of many valuable plant species, lessening in the area of severely sensitive ecosystem like high altitude pastures, snow cover peaks and important glaciers.Changes in the phenology of some plant species, which include change in time of flowering and seed formation.Changes in the habitat, which is fortunate for new alien weedy and invasive species.Increases fire risk in the sub-moderate and temperate dry deciduous and pine forests.Increases productivity of some grass species from the high altitude regions.Adverse impact on the timber production of forest.Effect on the agro-systemChanges the pattern and time of cropping.Shortening the maturity period of some winter crops, which are traditionally impo rtant constituent of mountain agriculture.Increase in the pathogen survival rate and crops are more pliable to pest, insect and fungal diseases.Decline in the yield productivity of some traditional crops whereas increasing temperature may also be favour the productivity crops like wheat.Decline in the yield of some horticultural fruits which needs demoralize effect for their fruit development as seen in sheath of orchard apple tree fruit production.Uncertain high precipitation leads to destruction of crop productivity during flowering, seed formation and maturation time.Effect on natural systemAccelerate intensity of glacier melting.Reduces area under snow cover and changes the time of snowmelt and snowfall at high-elevated ecosystems.Adverse impact on the seasonal runoff, freshwater availability.Increases the incident of landslides in mountains, drought condition and sever overeat condition at lowland regions.Soil properties and process like native be decomposition, leachin g and soil-water relation were influenced by increase temperature.Socio-economic conditions of the humankind severely affectedReduction in the area of pasture adversely affect the local pastoral rescue, as most of the local livestock of the transhumant and adjoining lowland peoples depends on the high altitude pastures in Garhwal in the summer season.Impact on the timber, medicinal plants and agriculture in the high altitude region in some extent gives negative results to the related industries.thriftiness through the hydropower generation is affected.Change in the social culture of the peoples living at high altitude regions, i.e. the time of the migration of the transhumant in Garhwal in recent affected due to the adverse climatic conditions. Which also affect their source of economy like agriculture, wool based occupation etc.Changes were also seen in the health conditions of the people living in high altitude, peoples of these regions now more worried about the heat stresses, v ector borne diseases, respiratory, eye derangement etc.Status of many endangered wildlife fauna in the Himalayan region affected, and changes in the behavioural and seasonal migration of the animal species can be possible. duck Distribution of some major plant species at different altitudinal belt of Garhwal Himalaya.Altitude (m asl)Plant species500- 1400Shrubs Zizyphus xylopyrus, Woodfordia fructicosa, Trees Rhododendron arboreum, Shorea robusta, genus Dalbergia sisso, Acacia catechu, Adina cardifolia, Terminalia, cassia fistula, genus Mallotus philippensis, Bombax ceiba.Agele,1500-2400Herbs Clematis montana, Anemone rivularis, A. obturiloba, Ranunculus hirtellus, genus Thalictrum chelidonii,Barbarea vulgaris, silene indica, Malvia verticillata, Geraanium nepalense, genus Fragaria indica, Potentilla fulgens Epilobium pulustre,Bupleurum falcatum, Aster peduncularis, A. thomsonii, , Gentiana aprica etc.Shrubs Prunus cornuta, Rosa macrophylla, Zizyphus xylopyrus, Woodfordia fructic osaTrees Rhododendron arboreum, Shorea robusta, Dalbergia sisso, Acacia catechu, Pinus roxburghii,P. wallichiana, Quercus leucotricophora, Q. semecarpifolia, Adina cardifolia,2500- 3400Herbs Anemone rivularis, A. obturiloba, Ranunculus hirtellus, Thalictrum chelidonii, T. minus, T. elegans, Aquilegiaa pubiflora, genus Caltha palustris Clematis montana, Clematis barbellata, Delphinium vestitum, genus Podophyllum hexandrum, Corydalis cornuta, Arabis nova, Viola canescens, Silene edgeworthii, S. Indica, Stellaria monosperma, Geranium collinum, G. himalayense, genus Trigonella emodi, genus Geum roylei, Potentilla fruticosa, P. fulgens, P. gelida, P. leuconota, P. polyphylla etc.Grasse Sedge Carex cruciata, Agrostis pilosula,Poa supina, P. alpina, Danthonia.Shrubs Cotoneaster macrophylla, Cotoneaster acuminatus, Lonicera, Salix, Rubus foliolosus, spirea bella, Berberis glaucocarpa, Myricaria bracteata, Skimmia laaureola, Astragallus candolleanus, Rosa macrophylla. Ribes himalense,Trees Betula utilis, Taxus baccata, Rhododendron campanulatum, Alnus nitida, A. nepalensis, Abies pindrow, Cedrus deodara, Pinus wallichiana, Acer ceasium, Junipers3500-4400Herbs Cypridium elegans*, C. himalaicum, Epipogium aphyllum, Dactylorrhiza hatagirea, Listera tenuis, Neottianthe secundiflora, Aconitum balfouri, A. falconeri, A. heterophyllum, A. violaceum, Ranunculus pulchellus, Thalictrum alpinum, Podophyllum hexandrum, Acer caesium*, Meconopsis aculeate, Corydalis sikkimensis, Megacarpaea polyandra, Astragallus himalayanus, Nardostachys graandiflora*, Picrorhiza kurrooa*, Pleurospermum angelicoides, genus Saussurea costus*, S. obvallata, angelica glauca, Ribes griffithii, Lonicera asperifolia, Waldhemia tomentosa, Primula glomerata, Arnebia benthamii, Geranium pratense, Impatiens thomsonii, I. racemosa, Dioscorea deltoidea*, Allium humile, A. stracheyi*, A. wallichi, clintonia udensis, Thamnocalamus falconeri, Orobanche alba, Sedum ewersii, S. heterodontum,Pimpnella diversifolia , Morina longifoliaGrasse Sedge genus Elymus thomsonii, Agrostis munroana, Calamagrostis emodensis, Danthonia cachemyriana, Festuca polycolea, Poa pagophila, Stipa roylei, Carex infuscate, C. nivalis, Kobresia royleana, K. duthei etc.Shrubs Cotoneaster duthiana, Cotoneaster acuminatus Hippophae tibetana, Rosa sericea, Sorbus macrophylla, S. ursine, Rhododendron anthopogon,Trees Sorbus aucuparia, Cedrus deodara, Betulla utilis,4500- aboveHerbs Oxygraphis glacialis, Ranunculus pulchellus,Corydalis bowerii, madwort canescens,Draba altaica, Silene gonosperma, Potentilla sericea, Sedum bouverii, Saussurea obvallata, S. simpsoniana, Christolea himalayensisLiterature citedRau, M. A. (1975). uplifted altitude flowering plants of west Himalaya. BSI, Howrah, India, pp.214.Singh, D. K. and Hajra, P. K., in Changing Perspectives of Biodiversity Status in the Himalaya (eds Gujral, G. S. and Sharma, V.), British Council Division, British High Commission, Publ. Wildlife Youth Services, New Delhi , 1996, pp. 23-38.Dunne, J.A., Harte, J. and Taylor, K. (2003). Sub alpine Meadow Flowering Phenology Responses To mood Change Integrating Experimental And Gradient Methods, Ecological Monographs 73 (1), pp. 69-86.IPCC (2001). Climate Change-2001 Impacts, Adaptation and Vulnerability, contribution of Working Group II to the Third Assessment Report of the Intergovernmental Panel on Climate Change.Kriticos, D.J., Sutherst, R.W., Brown, J.K., Adkings, S.W. and Maywald, G.F. (2003) Climate Change and The capability Distribution of an Invasive Alien Plant Acacia nilotica ssp.indica in Australia, journal of use Ecology, 40 111-124.Nautiyal, B.P., Prakash, V and Nautiyal, M.C. (2000). Structure And Diversity Pattern on An altitudinal Gradient In An Alpine Meadow Of Madhyamaheshwer, Garhwal Himalaya, India. Indian daybook of environmental Science 4(I). 39- 48.Nautiyal, M.C., Nautiyal, B.P. and Prakash, V. (2001). Phenology And Growth Form Distribution In An Alpine surf At Tungnath, Garh wal Himalaya. Mountain Research and Development, Vol. 21, No. 2, 177-183.Price, M.V. and Waser, N.M. (2000). Responses of sub alpine meadow vegetation to four year of experimental warming. Ecological ApplicatiAlpine Plant Biodiversity in the Central HimalayasAlpine Plant Biodiversity in the Central HimalayasAlpine Plant Biodiversity in the Central Himalayan Region Perspective of Global Climate ChangeSummaryIncrease in surface temperature at global scale has already affected a diverse set of physical and biological systems in many parts of the world and if it increases at this rapid rate then the condition would be worst one could have ever thought off. Garhwal Himalaya, major part of the great Himalayan mountainous system is also much sensitive and vulnerable to the local, regional and global changing climate. Due to strong altitudinal gradient, varied climatic conditions and diverse set of floral and faunal composition, the impact of climate change seems to be much higher. This pap er highlights some important features of the changing pattern of vegetational composition, distribution and impact of climate change on the phenological aspect of major alpine plant species present in the Garhwal Himalayan region. It also shows cumulative changes, which operate at local level but are globally pervasive. These cumulative changes include change in the land cover/ land use and other anthropogenic activities, which are related to the climate change. Overall biodiversity in the Himalayan region has been depleted as the consequences of complex and multitude pressure of climate change. The depleted biodiversity has indirectly affected the socio-economic development of the local communities on which their sustenance depends and is inherently critical to the consideration and management of natural resource.IntroductionPlant diversity and StatusThe varied altitudinal, climatic and topographical conditions in the Himalaya results in different types of microhabitats. Geographic isolation, glaciations, evolution and migration of the species in the past all together have contributed to the high level of biodiversity in this mountain system. As per genetic, species and ecosystem level resources, Himalaya is one of the hotspots of biodiversity in the world, which represents about one-tenth of the worlds known species of high altitude plant and animal species. Some parts in the Himalayan region are center for origin of many crops and fruit species and are important source of gene for their wild relatives. The floral diversity of this region shows assemblage of many endemic and exotic species of plants from the adjoining regions. A large number of western Himalayan flora in the Garhwal Kumaon region seems to have been invaded from Tibet, western China and adjoining north-east Asia (Rau, 1975).In the present scenario biodiversity seems to have been depleted in these regions due to land degradation, habitat fragmentation, increasing population pressure, over exp loitation of bio-resources and finally due to the changing pattern of the climate. Nearly 10% of flowering plants are listed under various categories of threatened species. Red Data Book of Indian plants listed about 620 threatened species, of which, 28 are presumed extinct, 124 endangered, 81 vulnerable, 160 rare and 34 insufficiently known (Nayar and Sastry, 1987, 1988), however, Red list of threatened plants indicates 19 species as extinct. Among others, 1236 species are listed as threatened, of which, 41 taxa are possibly extinct, 152 endangered, 102 vulnerable, 251 rare and 690 of indeterminate status (IUCN, 1997). From the Himalayan region the important plant species included in threatened categories are mostly the valuable medicinal and aromatic plants, which, support the economic condition and health care system of the local communities.It is well known that, in the context of the present scenario of climate change especially due to global warming many of the high-elevated e cosystems are severely sensitive and vulnerable. Their fragility may accelerate the changes occurring in their composition and structure to the slight variations in climatic factors. These regions include glacier, alpine pasture/ meadows and timber line ecosystem, which are the important source of the seasonal runoff, freshwater, valuable medicinal and aromatic plants, grazing land, source of timber and wild edibles for the mankind.Future scenario of climate change According to the Third Assessment Report of Intergovernmental Panel on Climate Change (IPCC) 2001, average global temperature close to the earths surface has increased by 0.6 C 0.2 C since 19th century mainly due to the emission of CO2. If human beings do not act to reduce the present level of CO2 there will be additional increment in temperature of 1.4 C to 5.8 C in the next 40 100 year. Current information available on the pattern of future climate change through General Circulation Models (GCMs) suggested that the an nual mean warming would increase about 3C in the decade of 2050s and about 5C in decade of the 2080s over the land region of Asia. Precipitation would increase annually about 7% and 11% in decades of 2050s and 2080s respectively. There would be a decline in the summer precipitation that seems likely to be over the central part of arid and semi-arid Asia. GCM also showed high uncertainty in future projection of winter and summer precipitation over south Asia, because much of tropical Asian climate is noticeably associated with the annual monsoon cycle. In Central Himalayan region, through the assessment of people perception it is interpreted that, climate change resulted in the increase in warming, decline in rainfall during March- May, high rainfall during Aug- Sept instead of normal peak in July- Aug, decline in the snowfall intensity and winter precipitation in Jan-Feb instead of Dec-Jan (Saxena et al., 2004). This scenario can hardly trigger to think about the changing pattern of climate or its negative and positive impacts at local, regional and global level.Although assessment of future climate change scenario through some of scientific models needs a better infrastructure and high technological inputs, specific impact of climate change on different ecosystems can be discerned by comprehensive studies on long term monitoring of the different aspects of ecosystem which is lacking in the Indian context especially in the Garhwal Himalayan region due to poor infrastructure and management practices. So, as per as need concern in these remote areas the assessment of impact on the natural resources in future climate changes can be done through the site-specific sensitivity analysis and it can be related to the traditional knowledges of the peoples living in this particular region of the Himalaya. Sensitivity analysis would help to assess what will be happen if various climatic variables changed, and analysis also evaluates the positive or negative impacts of cha nging climate on the natural resources. This assessment would help us to make the local communities realize the importance of conservation and management practice so that the endangered and threatened species could be saved from becoming extinct. Assessment of vulnerability and adaptive capacity of the various ecosystems and to develop indigenous knowledge based coping mechanism are important to determine the impact of climate change. This also links the ecological processes to the social processes and appreciates the relationship between the biodiversity and ecosystem functioning.Climate change Impact on different vegetation zoneNatural ecosystems at high elevations are much more sensitive to the climatic variations (Ramakrishnan et al., 2003) or global warming then the managed systems. Their sensitivity is prominently attributed to their limited productivity during snow-free growing season (Price et al., 2000), low dispersal capability, geographically localized, genetically impove rished, highly specialized and slow reproducing ability of the high altitude plants (McNeely, 1990 WWF, 2003). As a consequence of global warming the present distribution of species in high altitude ecosystems projected to shift higher as results of upward altitudinal movement of the vegetation belts. Although the rate of vegetation change is expected to be slow and colonization success would depend on the ability of adaptation and interaction of the plant species with the climate and other associated species, weeds, exotic and invasive species. Their success also depends on their ecological niche width and their role in the ecosystem functioning. Increase in the temperature would result competition between such species and new arrivals. As the result, species which have wide ecological tolerance have an advantage to adapt and those which are at the edge of range, genetically impoverished, poor dispersal ability and reproducer are under the threshold of extinction.A likely impact of climate change is also observed over the phenological aspect of vegetation in the alpine, sub alpine and timberline zone. Changes in the pattern of snowfall and snowmelt in these mountain regions and increase in mean annual surface temperature has pronounce impact on the date and time of the flowering and other phenophases of certain valuable, keystone species of plants. Earlier snowmelt simulate early flowering in some early growing plants and possibly increase in surface temperature may extend the growing period and productivity of certain grass species in the cooler climatic region. There is a gradual decrease in the growing period from timberline to the snow line, Rawat and Pangtey, (1987) reported about 20 weeks growing period near timberline and barely 4-6 weeks above 5000 m asl. Thus, increase in the average temperature due to global warming the growing period of the vegetation would be seems to extend at high altitudes. Evidences of climate change through people perception in Garhwal Himalaya reveals that increase in the warming results decline in the yield of apple fruits and shortening the maturity period of winter crops, whereas, the production of cash crops like potato, peas and kidney beans under warm condition increases. Change in rainfall pattern, snowfall intensity will increase large-scale mortality and damage to the crops, which are close to the maturity on the other hand, Barley and wheat crop production is severely affected due to winter precipitation in months of Jan- Feb (Saxena et al., 2004).Vulnerability of different vegetation belts in the Garhwal Himalaya.Dominant tree species in the low and mid altitude zone have a wider range of distribution. Shorea robusta the climax species of lower elevation is distributed over moist to dry deciduous bio-climates in central India where temperature is much higher while rainfall is quite low. Quercus spp. the climax species at mid elevation is also distributed over a wide range (1100- 1800m) The m id altitude which is prevail by broad leaves and coniferous forest (Rao, 1994) mainly species of Quercus spp. and Pinus spp. on response to the warming may be replaced by the species like Shorea robusta and Terminalia spp. Warming also increases the chance of greater fire risk in dry or moist deciduous forests, these impacts on the forest can directly influence the local livelihood based on fuel and fodder (Ramakrishnan et al. 2003).Rhododendron arboreum is a very prominent forest species because of its red flowers covering almost the whole canopy. At higher elevations this species used to attain peak flowering stage in February / March but now due to warming flowering time in this species seems to shift in the months of January/February. The phenological calendar at lower altitude has thus shifted to the higher altitudes. Exact times of leaf fall, flushing, flowering and fruiting may vary depending upon the elevation indicating sensitivity of phenophases to temperature and moistu re stress regime. Flowering and fruiting start earlier about a month with increase in elevation by 600 m (increase in temperature by 2.4 degree C) in Rhododendron arboreum, Prunus cerasoides, Myrica esculenta, Pyrus Pashia and Reinwardtia indica in Central Himalaya. Leafless period in deciduous species like Aesculus indica and Alnus nepalensis is longer at higher altitude as compared to lower altitude. At higher elevation (1500-3300m) in Central Himalaya, evergreen and winter deciduous species occur equally across the elevation/temperature gradient. All across the elevation / temperature gradient, majority of tree species show vernal flowering. Species showing vernal flowering (before 15 June) increased in frequency and those with aestival flowering (between 15 June 15 September) decreased with increase in annual temperature drown based on the elevation gradient. Thus, change in the temperature would affect flowering and fruiting time of different species or also induce change in s pecies composition.Vegetation of the timberline in different parts of world not only differs in terms of species composition but also exhibit different types of species (Crawford, 1989). In some regions the timberline represents exclusively evergreen conifers while in some it represents totally deciduous broad-leaved trees (Purohit, 2003). In the central Himalaya the Betula utilis, Abies pindrow and Rhododendron campanulatum, are the native species of timberline (Rawal and Pangtey, 1993), and have a complex, spatial habitat and reservoir of large number of medicinal and aromatic plants and wild edibles. During recent past, timberline, the most prominent ecological boundary in the Himalaya where the sub-alpine forests terminates, has been identified as sensitive zone to environmental change and could be effectively modeled / monitored for future climate change processes.The species from tree-line have a narrow range of distribution, as temperature optima for most of these species is higher than the temperature in their natural habitats, warming will be expected to promote their growth but they may be threatened if they fail to compete with the changing climatic conditions (Saxena et al., 2004). Due to the over exploitation and changing global climatic condition many of the medicinal and aromatic plants in and around the timberline shrunk in size and distribution from their natural habitats and some of them are listed rare, threatened and endangered. Besides, the herbs some tree species of the timberline across the western Himalaya viz. Taxus baccata, Betula utilis etc. are also facing sever threats of depletion (Purohit, 2003). Most of the species valued by local communities have a poor soil seed bank, there could be large-scale local extinction of these species if seed production on a landscape scale decline (Saxena et al., 2004).Swan (1967) identified two parts of the alpine region i.e. above timberline (Lower alpine zone 300 -4000 masl) and higher alpine zon e (4000 masl snowline). Grasses and sedges are dominating members of alpine vegetation at lower altitude but they are characteristically replaced by non- grassy dwarf plant species at higher altitude near snowline. The area immediate above timberline and zone of stunted trees shrubs marks the alpine scrub. The vegetation of the lower alpine zone consists of dwarf shrubs, cushionoid herbs, grasses and sedges, Salix, Rosa, Lonicera, Ribes, Cotoneaster and Berberis etc. form the major shrub species at lower alpine zone (Kala et. al., 1998). The herbaceous flora of this zone represent spectacular array of multicolored flowers and include many short period growing cycle plant species. The major herbs of this zone are Potentilla, Geranium, Fritillaria, Lilium, Corydalis, Cyananthus, Anemone, Ranunculus, and Impatiens etc.The vegetation of the higher alpine zone is rather sparse, dotted with moraines, boulders and rocky slopes forming suitable habitat for the patches of shrubs e.g. Rhodo dendron lepidotum, Juniperus spp. Betula utilis and many species of colourful flowering plants, grasses and sedge etc. In the alpine with the onset of summer, the physical condition of the every patches of ground undergoes constant change, this is the root cause for the instability and succession of plants. Another feature of alpine plant distribution is that in the same habitat one could see the growth of several related or unrelated species and only one species dominate in the entire habitat almost to the exclusion of the other species. This difference may be due to the Physico- chemical properties of the soil. Initiation of growing season depends on the intensity of snowfall in the proceeding season and start of the melting of snow during spring (April May).In alpine region flowering is started during the month of May in some species, but in most of the species flowering occurs during June to late July and it goes up to early August (Nautiyal et al., 2001). Jennifer A. Dunne et al. (2003) reported that in experimental condition, increasing 2C average soil temperature during the growing season for every two weeks of earlier snowmelt flowering time is advanced by 11 day in the sub-alpine region. Senescence at community level was gradually starts from July to September depending on the growth cycle of the plant species in Central Himalaya (Nautiyal et al., 2001). However in a study conducted by Zhang and Welker (1996) in Tibetan Tundra alpine the community senescence, which actually starts in September was postponed until October under warmer condition and stimulates the growth of grasses. It indicates that the warmer condition as result of increase CO2 enrichment extend the growing period and increase in the grass productivity and distribution may suppress the growth of forbs, shrubs (Zhang and Welker, 1996), similarly the valuable medicinal plants also affected (Ramakrishnan et al., 2003). It is possible that timber productivity in the high altitudes/ longi tudes could increase as result of climate change, but it could take decades to occur and the newly form forests habitats are likely to retain lower level of native biodiversity due to loss of species that are unable to cope and some species will become more abundant and widely distributed (Alward et. al., 1999)Biotic invasion is another important cause of change in the geographical distribution of the plant species, which is derived or accelerated by the global change. Elevated CO2 might enhance the long-term success and dominance of exotic grasses and their shift in species composition mainly driven by global change has potential to accelerate fire cycle and may reduce biodiversity (Smith et al, 2000). The water use efficiency due to increase atmospheric CO2 can allow increase in potential distribution of Acacia nilotica spp. indica in Australia and increase temperature favour its reproductive life cycle (Kriticos et al, 2003). As the glaciers are receding at a fast rate the newly formed moraine belt is an excellent area to study the invasion of plants from the adjacent mountains and pastures.In recent several land uses and land covers of the high altitude is eroded due to the glacier melting, avalanches and land slides, which favour to extend the distribution of Polygonum polystachyum, a fast growing herb, is mostly found on freshly eroded slopes, past camping sites, river banks and avalanche tracks (Kala et. al., 1998). The other successful invaders found in these habitats are species of Lonicera and Berberis followed by Rosa and Ephedra. Increase temperature may results higher pathogen survival rate and most of the plant species will be severely threatened due to insect, pest and fungal disease.To the changing climate, plants can respond following possible ways firstly no change in their species composition but change in productivity and biogeochemical cycle. Secondly, evolutionary adaptation to the new climatic condition either through plasticity (i.e. sh ift in phenology) or through genetic response. Followed by emigration to the new areas, as warming observed in the alpine has been associated with upward movement of some plant taxa by 1-4 meter per decade on mountain tops and loss of some taxa that formally were restricted to higher altitude (Grabherr et.al., 1994). Ultimately, they may undergo extinction (Bawa and Dayanandan 1998, Ramakrishnan et al.2003). Most of the plant species changes over time through the process of succession, with pioneer species preparing the way for others, identifying the species present, the physical forms plant takes and the area they occupied are the way for observing change. All the changes involve dynamic and that are difficult or impossible to predict, natural ecosystems in this regard serve as a kind of natural laboratory, where natural mechanisms of change such as change in climatic condition and change in the feature of physical and biological systems observe practically. Appropriate management strategies need to developed in such a way that it may have to find a new balance between traditional conservation and maintenance of biodiversity and other ecosystem functioning.Effect on the vegetationUpward movement of the vegetation belt. It result change in the pattern of structure and distribution of many valuable plant species, Reduction in the area of severely sensitive ecosystem like high altitude pastures, snow cover peaks and important glaciers.Changes in the phenology of some plant species, which include change in time of flowering and seed formation.Changes in the habitat, which is favourable for new alien weedy and invasive species.Increases fire risk in the sub-temperate and temperate dry deciduous and pine forests.Increases productivity of some grass species from the high altitude regions.Adverse impact on the timber production of forest.Effect on the agro-systemChanges the pattern and time of cropping.Shortening the maturity period of some winter crops, which are t raditionally important constituent of mountain agriculture.Increase in the pathogen survival rate and crops are more susceptible to pest, insect and fungal diseases.Decline in the yield productivity of some traditional crops whereas increasing temperature may also be favour the productivity crops like wheat.Decline in the yield of some horticultural fruits which needs chilling effect for their fruit development as seen in case of Apple fruit production.Uncertain high precipitation leads to destruction of crop productivity during flowering, seed formation and maturation time.Effect on Physical systemAccelerate intensity of glacier melting.Reduces area under snow cover and changes the time of snowmelt and snowfall at high-elevated ecosystems.Adverse impact on the seasonal runoff, freshwater availability.Increases the incident of landslides in mountains, drought condition and sever flood condition at lowland regions.Soil properties and process like organic matter decomposition, leachin g and soil-water relation were influenced by increase temperature.Socio-economic conditions of the humankind severely affectedReduction in the area of pasture adversely affect the local pastoral economy, as most of the local livestock of the transhumant and adjoining lowland peoples depends on the high altitude pastures in Garhwal in the summer season.Impact on the timber, medicinal plants and agriculture in the high altitude region in some extent gives negative results to the related industries.Economy through the hydropower generation is affected.Change in the social culture of the peoples living at high altitude regions, i.e. the time of the migration of the transhumant in Garhwal in recent affected due to the adverse climatic conditions. Which also affect their source of economy like agriculture, wool based occupation etc.Changes were also seen in the health conditions of the people living in high altitude, peoples of these regions now more worried about the heat stresses, vecto r borne diseases, respiratory, eye disorder etc.Status of many endangered wildlife fauna in the Himalayan region affected, and changes in the behavioural and seasonal migration of the animal species can be possible.Table Distribution of some major plant species at different altitudinal belt of Garhwal Himalaya.Altitude (m asl)Plant species500- 1400Shrubs Zizyphus xylopyrus, Woodfordia fructicosa, Trees Rhododendron arboreum, Shorea robusta, Dalbergia sisso, Acacia catechu, Adina cardifolia, Terminalia, Cassia fistula, Mallotus philippensis, Bombax ceiba.Agele,1500-2400Herbs Clematis montana, Anemone rivularis, A. obturiloba, Ranunculus hirtellus, Thalictrum chelidonii,Barbarea vulgaris, Silene indica, Malvia verticillata, Geraanium nepalense, Fragaria indica, Potentilla fulgens Epilobium pulustre,Bupleurum falcatum, Aster peduncularis, A. thomsonii, , Gentiana aprica etc.Shrubs Prunus cornuta, Rosa macrophylla, Zizyphus xylopyrus, Woodfordia fructicosaTrees Rhododendron arboreum, Sh orea robusta, Dalbergia sisso, Acacia catechu, Pinus roxburghii,P. wallichiana, Quercus leucotricophora, Q. semecarpifolia, Adina cardifolia,2500- 3400Herbs Anemone rivularis, A. obturiloba, Ranunculus hirtellus, Thalictrum chelidonii, T. minus, T. elegans, Aquilegiaa pubiflora, Caltha palustris Clematis montana, Clematis barbellata, Delphinium vestitum, Podophyllum hexandrum, Corydalis cornuta, Arabis nova, Viola canescens, Silene edgeworthii, S. Indica, Stellaria monosperma, Geranium collinum, G. himalayense, Trigonella emodi, Geum roylei, Potentilla fruticosa, P. fulgens, P. gelida, P. leuconota, P. polyphylla etc.Grasse Sedge Carex cruciata, Agrostis pilosula,Poa supina, P. alpina, Danthonia.Shrubs Cotoneaster macrophylla, Cotoneaster acuminatus, Lonicera, Salix, Rubus foliolosus, Spiraea bella, Berberis glaucocarpa, Myricaria bracteata, Skimmia laaureola, Astragallus candolleanus, Rosa macrophylla. Ribes himalense,Trees Betula utilis, Taxus baccata, Rhododendron campanulatum, Alnus nitida, A. nepalensis, Abies pindrow, Cedrus deodara, Pinus wallichiana, Acer ceasium, Junipers3500-4400Herbs Cypridium elegans*, C. himalaicum, Epipogium aphyllum, Dactylorrhiza hatagirea, Listera tenuis, Neottianthe secundiflora, Aconitum balfouri, A. falconeri, A. heterophyllum, A. violaceum, Ranunculus pulchellus, Thalictrum alpinum, Podophyllum hexandrum, Acer caesium*, Meconopsis aculeate, Corydalis sikkimensis, Megacarpaea polyandra, Astragallus himalayanus, Nardostachys graandiflora*, Picrorhiza kurrooa*, Pleurospermum angelicoides, Saussurea costus*, S. obvallata, Angelica glauca, Ribes griffithii, Lonicera asperifolia, Waldhemia tomentosa, Primula glomerata, Arnebia benthamii, Geranium pratense, Impatiens thomsonii, I. racemosa, Dioscorea deltoidea*, Allium humile, A. stracheyi*, A. wallichi, Clintonia udensis, Thamnocalamus falconeri, Orobanche alba, Sedum ewersii, S. heterodontum,Pimpnella diversifolia, Morina longifoliaGrasse Sedge Elymus thomsonii, Agrostis munr oana, Calamagrostis emodensis, Danthonia cachemyriana, Festuca polycolea, Poa pagophila, Stipa roylei, Carex infuscate, C. nivalis, Kobresia royleana, K. duthei etc.Shrubs Cotoneaster duthiana, Cotoneaster acuminatus Hippophae tibetana, Rosa sericea, Sorbus macrophylla, S. ursine, Rhododendron anthopogon,Trees Sorbus aucuparia, Cedrus deodara, Betulla utilis,4500- aboveHerbs Oxygraphis glacialis, Ranunculus pulchellus,Corydalis bowerii, Alyssum canescens,Draba altaica, Silene gonosperma, Potentilla sericea, Sedum bouverii, Saussurea obvallata, S. simpsoniana, Christolea himalayensisLiterature citedRau, M. A. (1975). High altitude flowering plants of west Himalaya. BSI, Howrah, India, pp.214.Singh, D. K. and Hajra, P. K., in Changing Perspectives of Biodiversity Status in the Himalaya (eds Gujral, G. S. and Sharma, V.), British Council Division, British High Commission, Publ. Wildlife Youth Services, New Delhi, 1996, pp. 23-38.Dunne, J.A., Harte, J. and Taylor, K. (2003). Sub alpine Meadow Flowering Phenology Responses To Climate Change Integrating Experimental And Gradient Methods, Ecological Monographs 73 (1), pp. 69-86.IPCC (2001). Climate Change-2001 Impacts, Adaptation and Vulnerability, contribution of Working Group II to the Third Assessment Report of the Intergovernmental Panel on Climate Change.Kriticos, D.J., Sutherst, R.W., Brown, J.K., Adkings, S.W. and Maywald, G.F. (2003) Climate Change and The Potential Distribution of an Invasive Alien Plant Acacia nilotica ssp.indica in Australia, Journal of Applied Ecology, 40 111-124.Nautiyal, B.P., Prakash, V and Nautiyal, M.C. (2000). Structure And Diversity Pattern Along An Altitudinal Gradient In An Alpine Meadow Of Madhyamaheshwer, Garhwal Himalaya, India. Indian Journal of Environmental Science 4(I). 39- 48.Nautiyal, M.C., Nautiyal, B.P. and Prakash, V. (2001). Phenology And Growth Form Distribution In An Alpine Pasture At Tungnath, Garhwal Himalaya. Mountain Research and Development, Vol. 21, No. 2, 17 7-183.Price, M.V. and Waser, N.M. (2000). Responses of sub alpine meadow vegetation to four year of experimental warming. Ecological Applicati
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