Posted on 20th Sep 2024 01:21:15 AM Botany
Introduction
Plant ecology is a branch of biological science dealing with the study of living organism as they occur in their natural homes. It is prominently a field subject and mostly involves field studies (Weaver and Clements 1988). Plant ecology study can help us to know how the plants live and develop or suffer in plant communities and how they survive.
Plant ecology is basically subdivided into two sub branches-
a) Autecology
b) Synecology
Autecology which deals with the study of inter-relationship between individual plant and forces (factor or conditions) affect its growth and development outside i.e, environment on the other hand, synecology in the study of origin, growth and development of plant communities. It includes their structure, formation and the causes which influence their distribution. For the proper understanding of synecology, one must have a good knowledge about synecology.
The later acts as the foundation to build up the knowledge about plant communities.
Plant synecological study deals with the vegetation, their environment and the habitats where they are living together. Plants stand still and wait to be count. Simple counts of the number of individuals, however, fail to reveal the dynamic nature of plant populations. So it is essential to make ecological survey for months, for years together in order to asses different qualitative and quantitative characters of plant communities (Harper, 1966).
Bangladesh is a riverine country and its climate is tropical monsoon and moderate. Average annual temperature of Bangladesh is 25°c (75°F) which is suitable for vegetation growth and reproduction. Rainfall of Bangladesh is not equal at all the year round and in all the regions. Average annual rainfall of Bangladesh is 75". Permanent and temporary watershed bodies in Bangladesh. The temporary watershed bodies become filled up with water during the monsoonic rainfall. But in dry season some of them become completely dry.
The Rajshahi University Campus is one of the most beautiful campus in Bangladesh. There are many deep water ponds, temporary watershed bodies and wet lands in this campus. These water bodies show luxuriant vegetation which show some changes in different seasons. During the rainy season, these water bodies become field up with water. Many free-floating, submerged, rooted, floating leaved plants together with rooted emergent (amphibious) plants grow profusely. During the summer and winter seasons, these water bodies dry up and mostly amphibious plants grow there. But now-a-days, farmers cultivate paddy in these decided up water bodies during these seasons. So there is change in habitats and many aquatic plants and animals inhibiting there face danger. These preliminary investigation was undertaken to study the flora of ponds with their taxonomic position and their economic importance.
Vegetation is the sum total of plants, covering an area. It may be a forest with trees, herb and ground layer plants. Plants are still and wait to be counted. Simple counts of the number of individuals, however fail to reveal the dynamic nature of plant population. So it is essential to make ecological survey for months or years together in order to assess different qualitative and quantitative characters of plant communities (Harper, 1966).
This study was carried out with the following objectives-
1. To determine the composition and quantitative characters of the vegetation during the survey period.
2. To determine the morphological characters and economic importance of some common herbaceous plant.
Description of the Study Area
Location
The study area was located within the Rajshahi University Campus at 24°13 East longitude in the district of Rajshahi.
The study was conducted in the four ponds of Rajshahi University Campus. The position of the ponds were as follows-
1. Pond A: At the back side of 3rd Science Building.
2. Pond B: At the eastern side of Taposhi Rabeya Hall.
3. Pond C: At the back side of Fine Arts Department.
4. Pond D: At the western side of Mamataz Uddin Arts Building.
Climate :
The studied area enjoys a tropical climate, characterized by hot summer and rainy season. The hot summer season extends from April to June, and rainy season extends from July to August receiving average rainfall of 151.25 mm of course this value fluctuates from year to year.
Materials and Methods
The present work is mainly based on vegetation investigation in four ponds of Rajshahi University Campus. The investigation involved survey of the flora in the selected area at monthly interval. The vegetation survey method used in the present survey was point quadrate. The experimental work consisted of field observation or survey work.
Field observation or survey work :
The flora of the studies area were listed by point quadrate method and recorded in the working sheets.
Sampling of vegetation :
A point quadrate was used to study vegetation. Individual plant species touching the sticks of point quadrate was counted and recorded in the working sheets. Unidentified plant special were collected for identification.
Treatment of Phyto-sociological Data :
The data of plant species obtained from 4 ponds at different places were analyzed by appropriate formula which are as follows :
Importance Value Index (IVI) = R.F + R.D + D.A
Where,
R.F = Relative Frequency
R.DF = Relative Density and
R.A = Relative Abundance
The IVI values for all the plants in each ponds were then calculated. 10 plants possessing the higher IVI values of the 4 locations were studied taxonomically. Their photographs were taken and their morphological characters and economic importance were studied.
Results
Synecological study of Macrophytes :
The vegetation survey work involved shady land flora on the watershed body of back side of 3rd Science Building, Eastern side of Taposi Rabeya Hall, back side of Fine Arts Building of Rajshahi University Campus. The vegetation were surveyed by the method of point quadrate. The flora belonging to different species met with were counted and listed in the working sheets and to determine their quantitative character (e.g: Importance value index).
A brief discussion on the results of this work is as follows :
Pond A :
The IVI together with R.F, R.D and R.A of the plant species found in the Pond A is shown in Table-1.
Here total number of plant species recorded were 30 in number. Among them Lippia nodiflora, Alternanthera Phyloxeroides, Nicotiana plumbaginifolia, Cyperus rotundus centella asiatica showed the highest IVI of 41.04, 37.78, 30.38, 29.67 and 29.27. Other plant species had lower IVI among these species.
Pond B :
The IVI together with R.F, R.D and R.A of the plant species found in the Pond B is shown in Table-2.
Here total number of plant species recorded were 16 in number. Among them Alternanthera phyloxeroides, Mikania cordata, Eichhornia crassipes showed the highest IVI of 53.55, 39.92 and 38.69. Other plant species had lower IVI among these species.
Pond C :
The IVI together with R.F, R.D and R.A of the plant species found in the Pond C is shown in Table-3.
Here total number of 21 plant species were recorded. Among them Alternanthera Phyloxeroides, Cynodon dc-ctylon, Lippia nodiflora commelina bengalensis showed the highest IVI of 41.4, 33.7, 31.00, 28.05. Other plant species had lower IVI among these species.
Pond D :
The IVI together with R.F, R.D and R.A of the plant species found in the Pond D is shown in Table-4.
Here total number of 18 plant species were recorded. Among them Alternanthera Phyloxeroides, Nicotiana Plumboginifolia, Polygonum hidropiper showed the highest IVI value of 35.33, 32.40 and 29.66. Other plant species had lower IVI values among all these species.
Taxonomic Study and Economic Importance
Ten plant which had higher IVI values in the four ponds during the study period were selected and their taxonomic study were done together with their economic importance. These are as follows :
Bengali name : হেলেঞ্চা
Scientific name : Alternanthera Phyloxeroides
Family : Amaranthaceae
Morphological character :
The leaves are opposite in pairs or whoris, with a distinctive mid rib and range in size from 5-10 cm. Its stems are long, branched, and hollow. Leaves and stems very greatly in sized and shape. Flesh, succulent stems can grow horizontal and float on the surface of the water, forming rafts. Fibrous roots arising at the stem nodes may hang free in water or penetrate into the soil.
Economic importance :
• The leaves and stem are used as vegetable and can be used as cattle fodder.
• Largely used in ceylon as a lactagogue, also as a wash for the eyes valued as a febrifuge in Malaya.
• The plant is much used as a galactagogue. In is given in boths for pruritus and phlyctena of young children.
Bengali name : ভূঁই ওকড়া
Scientific name : Lippia nodiflora
Family : Verbenaceae
Morphological character :
Leaves opposite, entite, denate or serrate, stems lay along ground and root. Flower pink, attracts bees, liny lilac puffs. Life form hemicryptophye. Hardy, no damage seen in low teens, Herb size is 3 to 6 inches, ever green, best in summer.
Economic importance :
• Infusion of leaves and tops used as carminative and diuretic.
• Demulcent used in gonorrhea. Also paste of leaves applied to sweelings and wound.
• Juice of roots used for gustric problems.
• Used for treatment of hook worms used as by women after child birth.
• Toasted tender stalks and leaves in infusion used for children indigestion. Infusion used in colds with fever.
• Paste or poultice of plant applied to swollen cervical glands erysipeals and to ehronic inodlent ulcer.
Bengali name : কচুরিপানা
Scientific name : Eichhornia crassipes
Family : Pontederiaceae
Morphological character :
E. crassipes area a free floating perennial aquatic plant native to tropical and subtropical South America. The leaves are 10-20 cm across, and float above the water surface. They have logy spongy and bulbous stalks. The feathery, freely hanging roots are purple black. An erect stalk supports a single spike of 8-15 conspicuously attractive flower, mostly lavender to pink in colour with six petals.
Economic importance :
E. crassipes is an excellent source of biomass plants are used to make furniture, handbags and rope. The plant also used as animal feed and organic fertilized although there is controversy stemming from the high alkaline pH value of the fertilizer.
The flowers are use for medicating the skin of horses. This sp. is a tonic.
Bengali name : থানকুনি
Scientific name : Centella asiatica
Family : Mackinlayaceae
Morphological character :
The stems are slender, creeping, stolons, green to reddish green in colour, inter connection one plant to another. It has long stalked green reniform leaves with rounded apices which lave smooth texture with palmately netted veing. The leaves are borne on pericladial petiols, around 2 cm. The root stock consists of rhizome, growing vertically down.
Economic importance :
• Centella asiatica may be useful in the treatment of anxiety and may be used as a promising anxoilytic agent in the future.
• The isolated steroid from the plant have been used to treat leprosy.
• It works for venous in sufficiency.
• Plant extract use in the treatment of memory enhancement and other neurodegenerative disorders is also well documented.
Bengali name : মোথা ঘাস
Scientific name : Cyperus rotundus
Family : Cyperaceae
Morphological character :
Cyperus rotundus is a smooth erect, and perennia weed with an extensive subterranean tuber system. It usually attains a height of about 30 cm, its stem are triangular in cross-section. It has fibrous roots that branch prolifically rhizomes, tubers, bulbs and inflorescence that consists of irregular compound umbels. Its leaves are mostly basal and linear in shape with a prominent mid rib.
Economic importance :
• Decoction of the plant are used for anti-infective and anti-flammatory properties.
• Modern alternative medicine recommends using the plant to treat nausea, fever and inflammation for pain reduction, for muscle relaxation, and many other disorders.
• Plant for treating digestive system disorders, dysmenorrhea and other maladies.
Bengali name : কানশিরা
Scientific name : Commelina bengalensis
Family : Commelinaceae
Morphological character :
Stem 60-90 cm long, slender, dichotomously, branched from the base up-wards; branches diffuse, glabrous or pubescent, creeping and rooting blow, leaves 2.5-7.5 by 1.3-3.8 cm, ovate or oblong, obtuse, sessile or shortly petiolate.
Economic importance :
The plant is bitter; useful in leprosy and “vata” (Ayurvala). In la Reunion, The plant is considered emollient and mucilaginous. It is must used in the from of a decoction as drink, lotion, bath.
The sutos prepare a medicine from the plant for treating barrenness in women.
Bengali name : দুর্বা ঘাস
Scientific name : Cynodon dactylon
Family : Gramineae
Morphological character :
Stem slender, prostrate, widely creeping, forming matted tufts, with slender erect or ascending flowering branches 7.5-30 cm high leaves 2-10 cm by 1.23-3 mm, narrowly linear or lanceolate finely acute to pungent, more or less glaucous, soft, smooth usually conspicuously distichous in the barren shoots and at the base of the stems.
Economic importance :
The plant aorid sweet, cooling : useful in biliousness, thirst, vomiting, burning sensation, bad taste in the mouth solicitation, epileptic, fits, tatigue, teprosy, scabies, skin diseases, dysentery fever, erysipelas, aplstexis (Ayurveda).
The roots crushed and mixed with curds are used in cases of chronic glect. A cold infusion often stops bleeding from piles.
Bengali name : বন তামাক
Scientific name : Nicotiana plumboginifolia
Family : Solanaceae
Morphological character :
An erect glandular-pubescent herb with trete stem. Large oblonglanceolate acuminate sessile leaves, the lower semiam-plexicaul and decurrent, and rosy or reddish pedicelled bracteate flower 4-5 cm. Long in many-flowered, usually panicled racemes.
Economic importance :
The leaves have a share bitter taste; heating, laxative, tonic, emetic, carmina-tive, anthelmintic; useful in bronchitis, asthma, caries of the teeth, skin diseases, scorpion bite, inflammations; cause bad eyesight (Ayurveda).
The leaves are narcotic, sedative, emetic. An ointment, made by simmering the leaves in lard, had been employed in curing old ulcers and painful tumors.
In Guiana, the leaves wormed and dipped in oil are applied to fresh wounds. An infusion is given as an enema.
Bengali name : পানি মরিচ
Scientific name : Polygonum hydropiper
Family : Polygonaceae
Morphological character :
This is an annual gladrous plant with a simple or branch, erect stem of a red, reddish or sometimes greenish colour from 8”-2 feet high. The lanceolate or oblong lanceolate, leaf are from 1”-4” long acute or acuminate at apex ciliate, undulate or slidely drised, tunctate and very acrid. The flower are borne in a panicled recene which is narrow, dropping interrupted and from 1”-3” long. The green calyx is usually 4 parts.
Economic importance :
Water piper is stimulant diuretic, ennena-gogue, antiseptic, diaphrodiadhoretic and besicant.
The infusion in cold water has been found in service-able in grabel, cold and cough and in milk; sickness and mix wheat bran in bowel complaints.
The infusion or a fermentation of the leaf has been benificially appled in chronic ulcer and hermorrhoidal tumers.
Bengali name : আসাম লতা
Scientific name : Mikania cordata
Family : Astera ceae
Morphological character :
Mikania cordata is a rapidly growing, creeping or twining perennial vine up to 10 m long. Stem branched pubescent to glabrous ribbed, from 3 to 6 m long leaves opposite cordate or tringular-ovate, blade 3 to 12 cm long. Fruit an achene, narrowly oblanceolate, often slightly curved, 2-3.5 mm long 0.4-0.5 mm in diameter with 5 light brown longitudinal ribs; cross section 5 sided, surface blackish brown, popus mostly persistent.
Economic importance :
The plant is used as a cover crop to prevent erosion and the leaves are used in some places as a soup vegetable.
Decoction is given for caught and the leaf juice is a remedy for sore eyes.
The infusion of the plant is given in affections of the stomach and intestine.
The leaves are used for rubbing on the body against it ches, for poulticing circumcision wounds and the decoction used for treatment of gastric ulcer.
Discussion
The four ponds in Rajshahi University Campus were studied by point quadrate method for four months (April, May, June, July). The plant species found in these ponds are listed in Table from 1-4. The macrophytic plant species found in these ponds were of more or less similar life form. Most of the plants are macrophyte. Alternanthera phyloxeroides show the highest IVI, other species with high IVI values were Lippia nodiflora, Mikania cordata, Eichhornia crassipes, Cynodon dactylon, Polygonum hydropiper, Cyperus rotundus etc. These water shed bodies have many other economically important plant species. Ten of these plant species were selected. Their morphological character, taxonomic position and economic importance were studies.
Many of these temporary watershed bodies (ponds) become dry during the summer season and these are then used for cultivation of rice and other similar crops. In this way many of the economically important plants does their habitat and disappear. This is a great threat for our biodiversity status. So these water shed bodies should be conserved at any cost.
Macrophytic, Flora, Economic, Importance, Autecology, Synecology, Individual, Plant, Ecology, Biological, Science, Environment, Rajshahi, University, Campus, Pond, Climate, Vegetation, Investigation, Synecological, Macrophytes, Alternanthera, Phyloxeroides, Lippia, Nodiflora, Eichhornia, Crassipes, Centella, Asiatica, Project
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