Diversity , distribution , indigenous uses and conservation prioritization of the economically important floristic diversity in Nadaun Block of Hamirpur District , Himachal Pradesh

The present study was carried out in 11 representative villages in Nadaun Block of Hamirpur district in Himachal Pradesh. Total 265 economically important species belonging to 81 families and 211 genera includes 78 species of trees, 46 shrubs and 141 herbs were records. The dominant families were Poaceae (20 species); Fabaceae (18 species) and Asteraceae (14 species). Twenty eight (28) families were monotypic. The inhabitants use these species as medicine (210 species), wild edible/food (109 species), fodder (88 species), fuel (42 species) for religious purpose (23 species), making agricultural tools (6 species), timber (12 species) and miscellaneous (12 spp). It was found that out of 265 economically important species recorded, 26 were found to be native to the Himalayan region, 10 species native to the Himalayan region and adjacent countries and states, 243 species were nonnatives. Out of the total recorded species, one species has been categorized as critically endangered, four species endemic, seven species near endemic and 14 species vulnerable.


INTRODUCTION
Himalaya meaning "abode of snow" is one of the largest mountain chains in the world, where floral and faunal diversity vary extensively with climate from one region to another.The Indian Himalayan Region (IHR) covering approximately 4,19,873 km 2 includes parts of Jammu and Kashmir, Himachal Pradesh, Uttrakhand (Garhwal and Kumaun), West Bengal (Darjeeling Hills), Sikkim, Arunachal Pradesh and other north eastern states.The present paper focused on diversity, distribution, indigenous uses and conservation prioritization of the economically important floristic diversity in Nadaun Block of Hamirpur district, Himachal Pradesh.This region supports about 18,440 plant species, out of which 27% are endemic to the Himalaya (Samant, 1998).1748 species of medicinal plants with various traditional and modern therapeutic uses (Samant,1998), 675 species of wild edibles (Samant and Dhar, 1997), 279 species of fodder (Samant, 1998) and 155 sacred plants (Samant and Pant, 2003) have been reported from the Indian Himalayan Region(IHR).

Study area
The State of Himachal Pradesh (30° 22' 4" to 33° 12' 40" N latitudes and 75° 47' 55" to 79°04' 20" E longitudes) includes the parts of Trans and North Western Himalaya.Of the total area, 66.45% is under forests.Of the total forest, 20.45% area is under Protected Area Network and 3.41% area under reserve forests.
The present study was conducted in eleven representative villages: Kangoo, Dhaneta, Nadaun, Bara, Jalari, Rangas, Ghaloo, Pakkabharo, Manjhali, Jolsappa, and Kunna road.Nadaun Block is located at 31°47′N 76°21′E31.78°N76.35°E.It is not a typical "Hilly and Chilly" type of climate in Nadaun Block as it is closer to the plains.Mainly humid sub-tropic zone occur.The mean annual temperatures vary from 20-24°C and mean annual precipitation is 1180 to 1900 mm.There has been a report of snow only once in Nadaun in 2012.Agriculture and horticulture are the amongst major livelihood options of the villages.The study area is highlighted in the Figure 1.
Eleven representative villages were selected to take information on the economically important floristic diversity and their utilization pattern by the inhabitants.Further, knowledgeable persons including village Vaidhyas from each village were interviewed.Information on the local names, altitudinal range, life forms, part(s) used, and use values including indigenous knowledge and practices were gathered.
Fresh samples of the useful species were collected and identified with the help of available literature and floras (Pangtey et al., 1991;Purohit and Samant, 1995;Samant and Pangtey, 1995;Sharma and Singh, 1996;Kala et al., 1998;Singh and Rawat, 2000;Kaur and Sharma 2004).The information was compiled and analysed for the utilization pattern following Samant, (1998).

Indigenous uses
Out of the 265 economically important species, 210 species were used for curing various diseases/ailments.For example, leaves of Amaranthus hybridus is used in diarrohea, dysentery and eczema; shoots of Adhatoda vasica is used in for cold, cough, bronchitis, early asthma, fever, sedative and as antiseptic; Phoenix humilis is used in sprain; roots of Hedychium spicatum is used for the treatment of asthma, bronchitis, eye problems, gastric dysfunction, as tonic and blood purifier; roots and leave of Strobilanthes atropurpureus is used as antidote for snake bite, bronchitis, pneumonia, wounds, headache and swelling; root of Rauvolfia serpentina is used widely applied in the case of intestinal disorders, in opacity of cornea, in the case of high fever, nervous disorders and in cholera; flower of S. oleracea is used in toothache, in throat problem, used as a stimulant and as diuretic.The remaining species were used for the treatment of various diseases/ailment (Appendix 1).

DISCUSSION
Plant resources are used by mankind to meet their daily needs.Man has been using plants as medicine, food (edible), fuel, fodder, timber, agricultural tools, for religious purpose and other purposes since time immemorial (Samant et al., 1996;Samant and Dhar, 1997).In spite of the efforts made by various workers, the information still remains fragmentary and most of the biodiversity rich areas remained unexplored or under explored (Samant, 1998).
Multipurpose utility of B. ceiba, Cannabis sativa, Terminalia chebula, Terminalia bellrica, Emblica officinalis, Dalbergia sissoo, Pinus roxburghii, Juglans regia, Melia azedaracht, Reinwardtia indica, Acacia catechu, Aegle marmelos and Pistacia integerrima indicated high pressure on these species.These species are facing high anthropogenic pressures in the area due to habitat degradation and over exploitation of propagating parts mainly roots/tubers/rhizomes of Aconitum heterophyllum, Acorus calamus, Rauvolfia serpentina, Hedychium spicatum, Gloriosa superb, etc, and fruits and seeds of some of the species which may lead to extinction of these species in near future.
The over exploitation and habitat degradation of some of the high value species have caused severe threat to these species.Such continued practices will cause the loss of these species and also, loss of moisture and humus content which will lead soil erosion and finally habitat degradation.It has been observed that due to unplanned collection of the resources, ecology of the forests has been seriously affected.Similar problems are also prevalent in the Nadaun Block.Therefore, adequate conservation measures have to be taken to maintain current status of the habitats, species and communities and for the effective management of the economically important plants of Nadaun block.Awareness among the inhabitants of the Nadaun Block needs to be created for the resource utilization techniques, so that sustainable utilization of the species could be done by the inhabitants.

Analysis of nativity and endemism of floristic diversity
Native and endemic species play an important role in assessing the conservation value of any habitat, community and ecosystem, for making a strategy and action plan for conservation and management of a particular biogeographic province, state, district, tehsil, block, watershed, valleys and catchments Out of the total 265 economically important species recorded from the Nadaun Block, 26 species (10%) were native to the Himalayan region, 10 species (4%) native to the Himalayan region and adjacent countries and states, 29 species (11%) were recorded from India, 19 species (7%) from India and adjacent countries, whereas 181 species (68%) were non-native representing other biogeographical regions such as Arabia, Australia, America, Africa, Japan, Malaysia, etc. (Figure 4).
The depleting population of native and endemic species and invasion by non-natives is a great concern due to the negative impacts of non-natives on the other species of a particular region and even entire ecosystems.The past studies have proved that nonnatives affect the hydrology and nutrient cycles of entire ecosystems .Such impact leads to the extinctions of the native and endemic species.

Diversity and distribution pattern of threatened plants
The economically important floristic diversity has been analyzed for rarity.Of the total recorded species, 1 species have been categorized as critically endangered (Rauvolfia serpentina), four endangered (Dioscorea deltoidea, Shorea robusta, Gloriosa superba and Withania somnifera) and 14 vulnerable (Acorus calamus, Pistacia integerrima, Asparagus recemosus, Berberis aristata, Berberis lycium, Capparis zeylanica, Terminalia arjuna, Costus specious, Cinnamomum tamala, Azadirachta indica, Thalictrum foliolosum, Aegle marmelos, Zanthoxylum armatum and Hedychium spicatum).There are other species facing habitat degradation and over exploitation and may be considered to be under near threatened and least concern categories.
Studies have been conducted to explore and identify the threatened plants including medicinal plants of the Indian Himalayan Region by some workers (Badola and Pal, 2003).However, in most of the studies, identification of threatened species has been carried out using qualitative attributes/observations, only.Assessment of status of the species using qualitative as well as quantitative attributes has been suggested by few workers (Samant, 1998).
Habitat degradation and overexploitation were the two major factors responsible for the population depletion of the economically important species.Most of the species were severely affected by both factors.
Further promotion of mass scale propagation through conventional and in vitro methods of such species and their rehabilitation in the in situ conditions or similar habitats may also help in conservation and management.The developed seedlings need to be disseminated among the farmers for mass scale plantation/cultivation.All the species categorized under various categories of rarity are traded, hence prioritized for conservation.

Figure 1 .
Figure 1.Map of the study area.

Figure 2 .
Figure 2. Utilization pattern of floristic diversity for various purposes

Figure 4 .
Figure 4. Native and non-native species of Nadaun Block.

Table 1 .
Taxonomic/habit wise description of economically important plants in the Nadaun Block.

/ habit group Family Genera Species Herbs Shrubs Trees
Appendix 1. Diversity, distribution, indigenous uses and conservation prioritization of the economically important floristic diversity in Nadaun Block of Hamirpur District, Himachal Pradesh.