3. AREA SURVEYED, GEOLOGY, CLIMATE AND VEGETATION

Transcription

1 3. AREA SURVEYED, GEOLOGY, CLIMATE AND VEGETATION India is gifted with heterogeneous landforms and varied topography constituting lofty mountains, the raverine deltas, high altitude forests, peninsular plateaus, variety of geological formations and climate endowed with temperature varying from arctic cold to equatorial hot, and rainfall. The soil, water, climate, flora and fauna constitute the basic natural resources and the national treasure of any country. North West India was selected for the present investigations on the lepiotoid and termitophilous mushrooms due to the richness of the area under investigation in natural healthy environment for mushroom growth with vast altitudinal variation representing plains, foot hills and higher reaches which largely fall within the altitude ranging from 250 to 3000 m (Table 1). This supports varied niches at different altitudes for the growth of these fungi. Approachability and socio-political condition of these areas were the other major considerations for selecting North West India for undertaking the present study. The present area of investigation has been restricted to North West India which includes Mandi, Chailchock, Barot, Bada Gram, Hamirpur, Nahan, Kullu, Manali, Shimla, Karsog, Kufri, Theog, Solan, Parwanoo, Nahan, Paonta Sahib, Rajgarh, Kangra, Baijnath and Palampur in H.P.; Chakrata, Mussoorie, Dehra Dun and Dhanoulti in Uttrakhand; Patiala, Rajpura, Fatehgarh Sahib, Ropar, Hoshiarpur, Chattbir and Chandigarh in Punjab. A temporary field laboratory was set up at each major station from where the sublocalities were surveyed thoroughly. 20

2 Map 1: Showing the area surveyed and routes followed during various fungal forays in North West India. June to October ( ) June to September (2009) July to September (2010) July to September (2011) 21

3 During excursions, every effort was made to explore the maximum area for the collection. Most of the species were collected from plains including some species from forested areas. The information with respect to the localities and sublocalities surveyed during the present investigation, along with their location (Latitude and Longitude) and altitudinal range is summarized in Table-I and shown in Map-I. The routes followed to explore the localities have also been depicted. 3.1 Geology and Soil The mushroom flora of a particular region largely depends upon type of vegetation, topography and altitude of the region. All these factors with respect to the present area of investigation and their possible impact on the overall growth of mushrooms has been discussed in the ongoing discussion. The present area of investigation constitutes the regions lying between the plains, Shiwalik hills and mountains. Shiwalik region primarily comprise the lower parts of the Himachal Pradesh and Uttrakhand and upper portion of Punjab. Many areas of Punjab and lower regions of Himachal Pradesh and Uttrakhand are largely plain while rest of the localities of Himachal Pradesh and Uttrakhand surveyed for collection of lepiotoid and termitophilous mushrooms are mountainous and fall in the outer and mid Himalayan region. Soil in different parts of the covered area is quite variable. In the upper regions of Punjab, soil is formed largely of barely coherant sand rocks with occasional clay, gravel, conglomerates and stones while in rest of the areas alluvial deposits of recent to subrecent period composed of coarsely beded stones, sand rock, conglomerates, clay, etc. is quite common (Manku, 2002). Uttrakhand region is also quite variable in soil type. It varies from deep alluvial and fertile soil of terai track to the recently laid down alluvial soil in Dun valley, thin fragile soil in Shiwalik hills, 22

4 black soil in temperate zone and arid bare soil in inner dry valleys. Soil texture of Himachal Pradesh is too variable. Shiwalik region mainly consists of detrital rocks, clay and conglomerates. The districts of Shimla and Sirmour have alluvial soil, while the remaining districts have forest and hill soil. The soil texture varies from clayey loam in the high rainfall areas to sandy loam in the Kangra region. 3.2 Climate The present area of investigation constitutes the diverse climatic conditions. It harboures both plains as well as hilly regions which experiences both hot and cold climate. Rainfall and temperature are obvious components of climate, which support a wide range of forest ecosystems and provide healthy environment for mushroom growth. Lower regions of investigated area presents greater extreme of both heat and cold than any other part of the study area. From the middle of April to the middle of September, it is extremely hot while from the beginning of October to the end of March the season is cool with warm bright days and cool nights. Dry heat is experienced in the first three months of hot season from mid April to the end of June. The temperature during this period ranged approximately from 25ºC to 45ºC. Monsoon winds normally cause the clouds and violent storms with heavy rainfall showers in July and August which is most favourable season for the collection of mushrooms. The amount of rainfall in this region varies between 250 mm to 1000 mm and the mean monthly range of temperature varies from 9 C to about 18 C. Shiwalik and sub mountains regions have an extreme climate, varying from hot summers to severe cold winters with heavy snow fall in its upper reaches. Snowfall at elevations of nearly 3000 m is about 3 m and lasts from the beginning of the December to the end of March. 23

5 Table 1: Localities and sub localities surveyed during the present investigation. Locality Altitude (m) Latitude Longitude Sublocalities Altitudinal Range (m) I II III IV V VI Shimla N E Shimla, Summer Hill, Tara Devi, Shoghi, Chandwick Fall Manali N E Kullu, Manali, Nagar Forest, Rohtang Pass, Children s Park Solan N E Solan, Barog, Chail, etc Nahan N E Nahan, Paonta Sahib Kangra N E Dharamshala, Naddi, Dal Lake, Mecleodganj, Kangra, Palampur, Baijnath, Maranda, Bada and Chotta Bhangal Hamirpur N E Kalahu, Jahu, Awah Devi Mandi N E Barot, Sunder nagar, Chailchock, Chachiyot, Sarkaghat, Nerchock Patiala N, E Chattbir, Baradari Gardens, Dear Park, Rajpura, Bahdurgarh, Punjabi University campus Fatehgarh Sahib E Aam Khas Bagh, Fatehgarh Sahib, Sirhind Ropar E Maharaja Ranjit Singh Bagh park, Boat House Hoshiarpur E Mahatiana, Dasuya, Mukeriyan, Khadiala Chandigarh E Rock garden, Sukhna Lake, 43 sector Uttrakhand ' N 79 15' E Korba, Chakrata, Dhanoulti, Deoban, Mussoorie, Dehra Dun Dharamshala has the highest rainfall of 3400 mm and the minimum towards the plains. Spiti is the driest area (below 50 mm rainfall) being enclosed by high mountains on all sides. The greatest intensity of hail has been marked within 15 km of the main ranges, particularly along the Dhauladhar in Kangra-Mandi and Kulu-Seraj tracts. Early fogs are characteristic of the outer valleys of Mandi, Barot region, 24

6 Bilaspur and Mussoorie. The occurrence of fog provides some insurance against delayed winter showers. The summer temperature ranges between 15 C and 38 C, while the winter temperature usually remain between 8 C and 15 C. 3.3 Vegetation The type of vegetation met within a particular area, depends upon the climate, topography, edaphic and the biotic factors (Champion and Seth, 1968). The wide range of altitude, temperature, rainfall and the soil results in a diversified flora. North West India, the present area of investigation has rich plant diversity. Broadly, the vegetation of this region has been categorized as tropical (up to 1000 m), subtropical ( m), temperate ( m) sub alpine and alpine (3300 m and above). The vegetational components of different altitudinal zones overlap frequently Tropical Zone: This zone consists of plains of Punjab and outer ranges of the Shiwaliks where the altitude ranges between m from the mean sea level. In the study area, it includes places like Patiala, Chandigarh, Kangra, Hoshiarpur, Nahan, Paonta-Sahib, Naina Devi, etc. There are mainly two types of the tropical forests that occur in this zone, namely tropical moist deciduous forests and the tropical dry deciduous forests. The tropical moist deciduous forests occur in areas where the annual rainfall is mm, the maximum temperature is 44 C and the minimum temperature is 18 C. In this type, further two subtypes of the forests can be distinguished, namely the moist Sal forest (Shorea robusta) and the moist mixed deciduous forest. In the moist Sal forest, Shorea robusta is the dominant species. It occurs almost in pure formations around Nahan, Sharanpur road, etc. Its upper limit is often occupied by Pinus roxburghii. Maximum numbers of Termitomyces and Lepiota species can be harvested in these forests during monsoon season. 25

7 Fig. 1 Karsog valley of H.P. Fig. 2 Barot valley of H.P. (Pure coniferous forest) Fig. 3 Loharadi valley of H.P. Fig. 4 Chakrata forest of Uttrakhand (Mixed forest) A variety of angiospermous components viz., Acacia nilotica, Dalbergia sissoo, Morus alba, Melia azadirachta, Eucalyptus tretecornis, Butea monosperma, Toona ciliata, Bombax ceiba, Mangifera indica, Cassia fistula, etc. are found in Faridkoat, Patiala, Chandigarh, etc region of Punjab. There are number of lepiotoid and termitophilous mushrooms in these areas. In the moist mixed deciduous forests, some of the commonly occuring trees are Dalbergia sissoo, Zizyphus jujuba, Bombax ceiba, Acacia catechu, A. fistula, Lagerstromia parviflora, Morus alba, etc. These forests are found over the larger parts of eastern Hoshiarpur and Nawanshehar districts, eastern Ropar district and hilly tracts of Nurpur Bedi block of Ropar district. 26

8 The tropical dry deciduous forests are developed in areas where the rainfall is less and relative humidity is low. Such forests are common at Hamirpur, Bilaspur, Parwanoo, some areas of Mandi districts, etc. Commonly occuring trees in this type of forest are those of Cassia fistula, Acacia catechu, A. arabica, Zizyphus jujuba, Dalbergia sissoo, Sapium insigne, Bombax ceiba, Mangifera indica, etc. Commonly occurring shrubs are Lantana camara, Euphorbia royleana, Adhatoda vasica, Carissa spinarum, Zizyphus nummularia, etc. Few species of Lepiota and Termitomyces were encountered in these forests during the extensive survey undertaken for the collection of lepiotoid and termitophilous mushrooms Subtropical Zone: This is an intermediate zone falling between the tropical and the temperate zones and is having an altitudinal range of m and an average annual rainfall of mm. Much of the rainfall occurs during the monsoon period. The forests of this zone are classified as montane sub tropical forests. These forests contain a mixture of tropical and temperate species. Such type of the forests are present at Solan, Barog, Chachiyot, Chailchock (Mandi), Dharamshala, Baijnath and Hamirpur. In such forests Pinus roxburghii forms the pure strands and occupies the hill tops and slopes. In the moist areas the evergreen trees of Quercus incana, Rhododendron arboreum, Lyonia ovalifolia occupy the gorges and their sides. Some other commonly occuring trees towards the lower side are of Eugenia jambolana, Ficus palmata, Acer oblongum, Pyrus pashia, Rhus semialata, Mallotus phillipinensis, etc. Ferns like Dryopteris marginata, D. cochleata, Adiantum venustum, A. incisum, Pteris vittata, Diplazium polypodioides, Ampelopteris prolifera and Lepisorus nudus, etc. are quite common and occupy the forest floor. Lepiotoid mushrooms are quite frequent in this region. 27

9 3.3.3 Temperate Zone: In this region the vegetation is a mixture of tropical and temperate species. The conifers like Pinus roxburghii, P. wallichiana and Cedrus deodara occupy the drier ridges. The common shruby plants like Berberis lycium, Principia utilis, Rhamnus virgata, Sarcoccoca pruineformis, etc. are also present. At shaded places are found the ferns like Asplenium dalhousie, Adiantum venustum, Lepisorus excavatus and Woodwardia radicans. Some other woody elements found in this region include Rhamnus purpureus, Pyrus lanata, Acer caesium, Berberis aristata, Aesculus indica, Qercus dilatata, Q. semicarpifolia, Rhododendron arboreum, etc. Picea smithiana, Cedus deodara, Taxus bacata, Abies pindrow and A. spectabilis are the coniferous elements found in this region (Figs. 1 & 2). Such types forests are found at places like Tara Devi (Shimla Hills), Bada and Chotta Bhangal (Kangra), Karsog, Lohardi valley, Kullu, Nagar area of Manali, Chail, Kothi, Glabba area of Manali, Mcleodganj, Dharamshala, upper reaches of Chail, Deoban, Dhanoulti, Mussoorie and Chakrata (Fig. 4). At some localities like Kothi, Bada Bhangal and Glaba in Manali the trees were very few and lopped. In such localities survey was difficult because of lot of under growth. At places including localities like Chail, Shimla, Manali, Barot (Mandi) Bada and Chotta Bhangal, Lohardi, Jatingri (Kangra), etc., pure crop of Cedrus deodara is met at an altitude between m. Sometimes there is a mixture of Pinus wallichiana, Abies pindrow and Picea smithiana (Fig. 2). In the temperate zone the species of Leucocoprinus are quite common Sub alpine and Alpine zone:- The subalpine forests are found in between the upper limit of the temperate zone and the lower limit of the alpine zone. Altitudinally this region falls between m. Juniperus spp. Abies pindrow, A. spectabilis, Betula utilis, Quercus semicarpifolia, etc. are commonly present trees. The Alpine 28

10 region extends from 3600 m and above. In the alpine zone, the vegetation in general is bushy in habit with short and much branched stems. No locality falling in the subalpine and alpine region was surveyed during the present investigation. 29