Wetland Flora of Gorewada International Biopark, Nagpur, India

Gorewada reservoir and adjacent area (1885 Ha) now converted into International Biopark abodes a variety of plant community to its credit. A study has been carried out to elucidate the aquatic flora with diverse plant wealth, indicator plants and their ecological status in wetlands of Gorewada catchment area.114 plants species with 33 families have been identified from the Gorewada wet land area. 67 species belong to dicotyledons and 47 are monocotyledons.


Introduction
Biodiversity accomplishes all vital requirements of organisms to complete their life cycle and amongst humans indirectly or directly dependent on both terrestrial as well as aquatic biodiversity, as both biodiversities provides natural resources in all ways to humans like cultural, economic, aesthetic, educational and scientific etc. Biodiversity covers all organisms like microorganism, plants and animals along with its all diverse genetic variations in species, varieties and populations in different habitats, ecosystems and in their natural areas, and its groups increases richness in natural environment [1].
Wetlands are vital parts of the hydrological cycle, highly productive, support exceptionally large biological diversity and provide a wide range of ecosystem services, such as food and fibre; waste assimilation; water purification; flood mitigation; erosion control; groundwater recharge; microclimate regulation; enhance aesthetics of the landscape; support many significant recreational, social and cultural activities, besides being a part of our cultural heritage [2].
The composition of a plant community is determined by a complex interaction of several biotic as well as abiotic factors including climate, soil type, position in the landscape and competition between plant species. Amongst which wetlands are the very important aquatic ecosystem, which maintains the balance in environment. Wetlands have seasonal variation in its floristic composition. Consequently, botanical explorations of wetland plants are necessary to gain more knowledge on species richness as well as their geographical distribution. Works on floristic studies of documentation of diversity of aquatic plants and wetlands flora in various water reservoirs and wetland areas of different states of India were carried out by many workers [3,4,5,6,7,8,9,10]. Besides these there are several researchers from Maharashtra state and its various districts and regions, explored the aquatic and wet lands plants diversity [11,12,13,14,15,16,17,18,19,20,21,22]. Nagpur is one of the greenest cities of India with 18 per cent of its area under forests and plantations, 17 per cent under cultivation and 2 per cent under water bodies [23]. To maintain ecological equilibrium, there is a need of documentation of floristic composition of wetlands, which plays a crucial role as pollution indicator. From this the assessment of conservation of threatened taxa which are associated with wetland habitats also carried out. In view of this fact, the present study is meant to prepare the documentation of the phytodiversity of wetland of Gorewada International Biopark (Proposed), Nagpur, the first exploration of the kind in this area.

Study Area
Proposed Gorewada International Biopark lies between latitudes 20 0 35' and 21 0 44' North and longitudes 78 0 15' and 79 0 40' East. It extends over to 1885 ha of reserved forests, in outskirts of Nagpur city. All area is divided into 7 beats (Compartments) viz. 790, 791, 792, 793, 794, 795, 796 and one water catchment area. Land is well drained and form catchment area of Gorewada Lake, known for its scenic beauty. Gorewada water reservoir, an area of around 57.93 sq. Hectare is situated on the eastern side of the proposed zoo and bio-park. Northern bank of the lake is made by beat number 796 and western side by beat number 795. Almost all compartments have well drainage system in the form of ponds and streams towards the water reservoir. The annual average rainfall of the area is 900 mm and the annual mean temperature varies from 10 0 C minimum to 45 0 C maximum [24].

Methods
For the study of wetland flora, the survey in and around ponds, lakes, streams with extensive field visits have been done in various time of the year to cover all the wetlands of the area in different seasons during 2008 to 2013.The different wetland of each 7 compartments along with water reservoir often visited are shown in map The methodology adopted for the data on taxa distribution within the forest range were collected particularly with the help of two sources-field observations and identification with pertinent literatures [25,26,27].Besides that the information on habit, habitat and flowering was carried out in the both dry and wet seasons. The identification of specimens was carried out by consulting relevant literature and regional floras [28,29,30,31] and morpho-ecological classification viz. I) Submerged anchored, II) Free Floating, III) Floating leaved anchored, IV) Floating shoot anchored,V) Emergent anchored and VI) Helophytes [32].

Results and Discussion
Exhaustive field visits to the all wetland areas in 7 compartments and area adjoining the water reservoir carried out in all seasons of the year and documented all floral components. The statistical analysis of the floristic components also carried out. A total of 114 species from 33 families were identified from the Gorewada wet land area. 67 species belong to dicot and 47 are monocots (Table No.2). Some of the major dominant wetland phyto-diversity are Hydrilla, Utricularia, Vallisneria, Ceratophyllum, Azolla, Eichhornia, Ipomea, Lemna, Trapa., Nymphoides indica, Spigelia anthelmia L. [33] etc. According to ecological classification, majority of the taxa belong to category V, i.e. muddy elements. Category I, submerged species are represented by Vallisneria, Nechmandra, Naias, Ceratophyllum and Hydrilla, While Ottelia, Aponogeton and Limnophyllum forms the floating leaves category, II. Typha and Ipomea fistulosa are the most frequenttaxa of category IV. (Table. No.1& Figure. 3). besides these, algae, aquatic fungi, bryophytes and pteridophytes are also major parts of the wetland ecosystem. The detailed list of floral components according to its habits and ecological class occurred in Gorewada International Biopark given below. (Table No. 1).    Wetland Indicator Categories based on differences in expected frequency of occurrence of wetland plant species [34], probability of occurrence in wetlands as opposed to upland habitats, with obligate wetland species having a percentage probability of occurrence in wetlands (OBL)> 99%; facultative wetland species (FACW), 67% -99%; facultative species (FAC), 34% -66%; facultative upland species (FACU), 1% -33%; and obligate upland species (UPL), < 1%. According to this, the dominant wetland  Table.3).
Gorewada Lake is one of the important water reservoirs of the Nagpur, from where supply of the drinking water to the different parts of the city takes place. At the same time its expanded marshy land provides suitable habitats for breeding of number of water animals. Large population of macrophytes of wetlands is provider of not only habitat but also the much needed food for number of organisms.

Conclusions
Wetlands have a great diversity of plants needing wetness of diverging extents. These plants are accordingly adapted to the local availability of water and many show transitions between annual and perennial forms and also their type of growth forms. Weed, a controversial class of plants, its invasion is a major problem in wetlands resulting in increased competition for resources such as water, light, nutrients and space [34]. Wetland plants can be threatened by changes in both surface water and groundwater levels as a result of human activities. Wetland plants are sensitive to changes in hydrology which result in a wetland having too much or too little water. The anthropogenic activities like deforestation; overgrazing and developmental activities etc. are causative factors for the acceleration of soil erosion and consequent siltation of wetlands. For successful implementation of conservation, involvement of people and nongovernmental organizations is crucial. People can be involved in de-siltation of lake, afforestation in the catchment area and generating awareness