Project on
Ecosystem With particular reference to Bangladesh
Prepared for: Dr. Khairul Azam Faculty, ENV107 North South University
Prepared By: Date of submission : 3/12/2008
Al Amin Redwanur Rahman
081162030
Table of Content
Sl No
Topic Name
Page No.
1
Introduction
1
2
Entities of ecosystem
2
Energy Flow and food chains in ecosystem
3
Ecosystem of Bangladesh
4
Different types of ecosystem in Bangladesh Aquatic ecosystem
5
2.1 3 3.1 3.1.1
Marine ecosystem
3.1.1.1
Freshwater ecosystem Soil ecosystem
3.1.1.2 3.1.2
Forest ecosystem
3.1.3 4
Ecosystem in different area
5 6 7 8 9 10
4.1
Urban area
10
4.2
Rural area
10
5
Ecosystem: state of equilibrium
11
6
Conclusion
12
Introduction:
A healthy environment is mandatory to for the survival of living things. Without a healthy environment non-living things also can’t exist. To have a healthy environment, a balanced balanced ecosystem ecosystem is essential essential.. Without Without a balanced balanced ecosystem, ecosystem, healthy environment environment is not possible. An ecosystem is a geographical area of a variable size where both living and non-living settings co-exist, interact & affect one another. Ecosystem encompasses all the parts parts of a living living enviro environme nment, nt, includ including ing the plants plants and animal animals, s, and the non-liv non-living ing components, such as water, air and solar energy. Ecosystems can vary greatly in size. Some examples of small ecosystems are tidal pools, a home garden, or the stomach of a cow. Larger ecosystems might encompass lakes, agricultural fields, or stands of forests. Landsca Landscapepe-sca scale le ecosy ecosyste stems ms encompa encompass ss larger larger region regions, s, and may includ includee differ different ent terrestrial (land) and aquatic (water) communities. Ultimately, all of Earth's life and its physical environment could be considered to represent an entire ecosystem, known as the biosphere.
Entities of the ecosystem:
An ecosystem is based on two entities. One is living things and another is non-living things. Living things are plant, human being, animals and insects. And non-living things are land, water, temperature, air, rock, solar energy. We can divide the entities of ecosystem in 4 parts. 1) Hydr Hydros osph pher eree (wat (water) er) 2) Lith Lithos osph pher eree (rock (rock & soil soil)) 3) Atmo Atmosp sphe here re (ai (air) r) 4) Biosphere Biosphere (human (human & other other living living organism) organism) Biosphere can be divided into two parts: a) Producers are autotrophic photosynthetic organisms. They can produce their own food. In terrestrial ecosystems, producers are predominantly green plants but inn freshwater and marine ecosystems, dominant producers are algae. b) Consumers are heterotrophic organisms that depend on producers for food. Among 4 types types of consu consumers mers herbivores feed feed dire direct ctly ly on gree green n plan plants ts whic which h are are prima primary ry consumers. Carnivores feed on other animals and are secondary or tertiary consumers.
Omnivores feed feed on both both plant plantss and animals; animals; for exampl example, e, humans humans eat both both leafy leafy vegetables and beef. Decomposers are organisms of decay and they are mostly bacteria and fungi. There are some cycles c ycles in ecosystem. Without those cycles ecosystem will collapse. Those cycles are: 1) Oxygen ygen Cycl Cyclee 2) Hydr Hydrol olog ogic ical al Cycl Cyclee 3) Nitr Nitrog ogen en Cycl Cyclee 4) Phos Phosph phat atee Cycl Cyclee 5) Biog Biogeo eoch chem emic ical al cycl cyclee If single of these cycle breaks down, whole ecosystem will break down.
Energy Flow and foo food d chains chai ns in ecosys ecos ystem tem :
The sun is the ultimate source of energy for nearly all life. From solar energy producers makes food and this energy flows to others by food chain & food web. Food chains indicate who eats whom in an ecosystem. It represents one path of energy flow through an ecosystem. Ecosystems have numerous interconnected food chains. In a food chain, each level of producer and consumers is a tropic level. Some primary consumers feed on plants and make grazing make grazing food chains; chains; others feed on detritus.
Ecosystems in Bangladesh: Ecosystem of Bangladesh includes all living & non-living things like people, animal, forest, land, river, Bay of Bangle. Bangladesh has a great ecosystem as its floodplains form one of the world's world's most important important wetlands. wetlands. These wetlands wetlands are home to hundreds hundreds of species of unique plants, fish, birds and other wildlife. People of Bangladesh are also dependent on these wetlands. These wetlands provide critical habitat for migrating birds and most most impor importa tant ntly ly a sour source ce of inco income me and and nutr nutrit itio ion n for for mill millio ions ns of peopl peoplee in
Bangladesh. The floodplain fishery plays a vital role in cushioning rural poverty and supplying animal protein to the poor and is an integral part of the culture and lifestyle of the Bengali people.
Different ecosystems of Bangladesh: Ecosystem of Bangladesh can be divided into three types. Three types of ecosystem are:
Aquatic Ecosystem
Soil Ecosystem
Forest Ecosystem
Aquatic Ecosystem: Bangladesh is a country of river. It has more than 300 rivers. Beside, lots of ponds exist in land area. Again it’s located by the side of Bay of Bangle. That means Bangladesh has a rich aquatic ecosystem. We can divide aquatic ecosystem of Bangladesh into two. They are: •
Marine
•
Fresh water
Marine ecosystem of Bangladesh: The location of the landward boundary of the coastal zone is a function of three basic geophysical processes: tidal fluctuations; salinity; and risk for cyclone and storm surges. The coastal zone of Bangladesh, affected by these processes, covers an area of 47,201 km, or 32% of the country, being the landmass of 19 districts. Around 35 million people, repr repres esent entin ing g 29% of the the popul populat atio ion, n, live live in the the coas coasta tall zone. zone. Many Many of the the coas coasta tall inhabitants are poor, and the population is exposed to both natural disasters and manmade made hazard hazards. s. Climat Climatee change change and sea-l sea-level evel rise, rise, induced induced by global global warmi warming, ng, also also compromise the ecological stability of the coastal zone.
The coastline is 710 km long, composed of the interface of various ecological and economic economic systems, systems, including mangroves, estuaries, estuaries, islands, islands, accreted accreted land, beaches, a penins peninsula ula,, rural rural settl settleme ements nts,, urban urban and indust industria riall areas, areas, and ports ports.. The territ territori orial, al, conti contigu guou ouss and and exclu exclusi sive ve econo economi micc zones zones exten extend d 12, 12, 18 and and 200 naut nautic ical al mile miless respectively out into the Bay of Bengal. The continental shelf reaches a breadth of 350
nautical nautical miles. miles. It is charac character terize ized d by low salini salinity; ty; predom predomina inantl ntly y muddy, muddy, sandy sandy or muddy-sand bottom conditions and high freshwater and sediment discharge. So far, 475 fish species of 133 genera, 5 spp. of marine turtles, 24 shrimp spp. of 5 families, 50 spp. of crabs, 301 spp. of marine marine mollusks, mollusks, and some 20 spp. of seaweed seaweed have been recorded recorded here. However, the ecology and distribution of most of these species are almost unknown . Lentic water ecosystems (standing water) cover around 3% of the coastal zone area. In combination with lotic water systems (running water), they support an extremely rich and diverse fish fauna: 260 spp. of indigenous freshwater, bony fish belonging to 145 genera and 55 families have been recorded so far. In addition, these ecosystems support a very large population of commercially important freshwater shrimp.
Freshwater: Bangladesh is a land of river. It was more than 300 rivers and lots of ponds. So it has a large freshwater ecosystem. We can divide freshwater ecosystem of Bangladesh in three basic types: •
Lentic: slow-moving water, including pools, ponds and lakes.
•
Lotic: rapidly-moving water, for example streams and rivers.
•
Wetlands: areas where the soil is saturated or inundated for at least part of the time.
The majority of the natural ecosystems of Bangladesh are wetlands. Intricate networks of rivers that drain into and inundate Bangladesh have created many riverine ecosystems in the country. The haors in the north-eastern parts of Bangladesh are probably the most complex of seasonally inundated wetlands. They switch between a vast vast basi basin n of wate waterr duri during ng the the monsoo monsoon n and a wellwell-net networ worked ked syst system em
of
smal maller ler
wetl wetlan ands ds
including biecls and khals in the summer. Surface water is the most severely impacted natural resource in the country.The haor basin basin is known for its rich biodiversity. There is little doubt that the seasonally inundated wetlands are amongst the most productive ecosystems. Among the whole haors are Considering the ecological value of the haor , the Tanguar haor has been declared a Ramsar site and an Ecologically Critical Area. The largest haor in the country is Hakaluki Haor, which extends over 18,000ha during the rainy season, and consists of more than 80 inter-connected beels. beels. The rich rich fish fish resources of Hakaluki support one of the largest inland fisheries in the country. Tanguar is an important “mother fisheries area”, where many species breed during the rainy season.
Soil ecosystem in Bangladesh: Before knowing about the soil ecosystem we should know about what is soil. Soil is the product of organism and climate acting on rocks. It is a complex, intimate mixture of minerals, organic matter, and organisms. Many kind of organisms (e.g. plants, microbes, vertebrate and invertebrate animals) are part of soil ecosystem. Plants are the ultimate source of carbon, which is a critical structural component of soil and source energy fueling the processes that occur with in the soils. Understanding the role of the soil in the farm ecosystem, knowing how to manage the land, are critical and difficult tasks facing the organic farmer. Soil ecosystem of Bangladesh refers to the micro animals live in the soil and how they interact themselves. In undisturbed soil, leaves and other organic debris accumulate on the where they broken down by the decomposers. Aerobic bacteria and certain small animals begin the process. These organisms organisms are joined joined by fungi, fungi, mites, mites, springtail springtails, s, small insects, insects, other other arthropods arthropods and earthworms earthworms assist the process process by consuming, consuming, mixing and transporti transporting ng materials. materials. Biological Biological activity is greatest when the soil is worm. Rhizophere organisms like plants roots leak or exude a large number of organic substances and continually slough off root caps into the soil. The most grou group p of larg larger er soil soil orga organi nism smss are are eart earthw hwor orms ms.. Eart Earthw hwor orm m perf perfor orms ms the the fina finall task task of mummification the conversion of decomposed organic matter to stable human colloids. In the process of borrowing, earthworms mix the subsoil with the topsoil and deposit their nutrient-rich castings on or near the soil surface. The presence of a large earthworm population indicates good soil fertility. Mites are the most abundant of the soil arthropods. Most mites are beneficial, feeding on micro-organisms and other small animals.
Forest ecosystem in Bangladesh: A forest ecosystem is a natural unit consisting of mostly plants, animals and microorganisms in forest area and functions together with all of non-living physical factors of the environment. environment. Logically, trees are an important component of forest forest research but the wide variety of other life forms and abiotic components in most forests means that other element elements, s, such such as wildli wildlife fe or soil soil nutrie nutrients nts are often often the focal point. point. Among Among forest forest ecosys ecosystem temss of Bangla Banglades desh, h, Sundor Sundorban ban is major. major. The Sundar Sundarban, ban, coverin covering g about about one million ha in the delta of the rivers Ganga, Brahmaputra and Meghna at the point where it merges with the Bay of Bengal, is the single largest block of tidal halophytic mangrove forest in the world shared between Bangladesh (62%) and India (38%), which supports a large, biodiversity-rich unique ecosystem. With its array of trees and wildlife the forest is a show showpi piec ecee of natur natural al hist histor ory. y. It is also also a cente centerr of econ econom omic ic acti activi viti ties es,, such such as extraction of timber, fishing and collection of honey. The area of Sundarban experiences a subtropical monsoonal climate with an annual rainfall of 1600-1800 mm and severe cyclonic storms. Enormous amount of sediments carried by the three rivers contribute to its expansion and dynamics. Salinity gradients change over a wide range of spatial and temporal scales. The Sundarban is intersected by a complex network of tidal of tidal waterways, mudflats and small islands of salt-tolerant mangrove forests, and presents an excellent example of ongoing ecological processes. The area is known for its wide range of flora and fauna. The most famous among these are the man-eating Royal Bengal Tigers Tigers, but numero numerous us specie speciess of birds of birds,, spotted spotted deer , crocodiles and snakes also also inha inhabi bitt it. it. The The
mangroves have been extensively exploited over centuries for timber, fish and prawns, honey, fodder, or converted for paddy and aquaculture and now it faces the serious challenges for its existence. Javan rhino, wild buffalo, hog deer, and barking deer are already already extinc extinctt from from the area. area. While While conser conservat vation ion effort effortss have focuse focused d on wildli wildlife, fe, particularly tiger, through creation of several sanctuaries and a biosphere reserve, reduced freshwater inflows are a serious threat as salinity is rising. Heritiera fomes (from which Sundarban derives its name), Nypa name), Nypa fruticans and Phoenix and Phoenix paludosa are declining rapidly.
Ecosystem of urban area: An ecosystem of urban society consists of several species. Cities are embedded in a larger ecosystem. But like any life supporting system; a city must need basic ecosystem needs. This is accomplished through the connections between city and surrounding environments. Ecosystem of big cities in Bangladesh like Dhaka, Chittagong, Sylhet, Rajshahi includes its population, ponds & rivers, roads & highways, offices & factories, transport and other facilities. People from these areas are as dep depend end mos mostly tly on rur rural al eco ecosys system temss for foo food d & ot other her dai daily ly ne neces cessar saries ies.. Peo People ple fro from m different part of the country come to these areas. Demand for food & housing is increasing. That’s why lots of skyscrapers are being built. As a result quantity of forest area & aquatic area like ponds & rivers are being destroyed.
Ecosystem of rural area: In rural area of Bangladesh like northern part of the country & other village are totally different from town area. Rural area ecosystem includes its population, population, fields, plants, cannels & ponds ponds and
other biotic and abiotic factors. People in these areas produce food and other crops and supplies the excess of their need. People of
rural area mostly
depend on
agriculture
& faming. They destroy
forest in
order to make house and collect fuel. They also destroy biodiversity by hunting wild life. Farmers use pesticides that enter in & pollute the environment.
Ecosystem : State of equilibrium ????? If we look look see see the the whol wholee scen scenar ario io of ecos ecosys yste tem m in Bang Bangla lade desh sh,, we will will find find a misbalanced situation. People are migrating to cities more and more. But cities don’t have enough ability to provide shelter, food & cloth. As a result skyscrapers and slums are being made. Also cities can’t provide everyone’s livelihood. As a result number of crime is increasing. People are becoming more dishonest. So a particular class of people is becoming becoming rich. They don’t care other other people. Again number number of factories factories & vehicles are increasing. These factories & vehicles increase carbon-di-oxide in atmosphere. As a result temperature is getting high.
In rural area, ecosystem is not in balance too. Number of land is becoming less. Productivity Productivity of land is going down. People are cutting down the forests. The nestling place of bird & living place of wildlife are being destroyed. Many species have already faced extinction. Many more species
are on the way to extinction. Chemicals and pesticides that are used in agriculture contaminates with river & pond water. As a result water gets polluted and people suffer from different disease and often die if they use polluted water. Climate of Bangladesh is changing. It’s becoming a threat to us. Most damaging effects of climate change are floods, salinity intrusion, and droughts that are found to drastically affect crop productivity almost every year. Due to climate change, fresh water will become scare, sea water level is rising, river banks are wearing down, chance to earthquake have increased.
Considering all these factors, we can say that ecosystem in Bangladesh is not in state of equilibrium.
Conclusion: It is well recognized to both the scientific and negotiating community that Bangladesh would be one of the most adversely affected country to climate change. Low economic strength, inadequate infrastruct infras tructure, ure, low leve levell of soci social al devel developmen opment, t, lack of inst institut itutional ional capacity, capacity, and a high higher er dependency on the natural resource base make the country more vulnerable to climate stimuli (including both variability as well as extreme events). That’s why we need to restore the state of equilibrium in our ecosystem. State of equilibrium in ecosystem is needed to have a healthy environment and sustainable sustainable future. We can do restore the state of equilibrium in our ecosystem ecosystem by doing followings: 1) En Ensu suri ring ng susta sustain inab abil ilit ityy 2) Ha Havi ving ng st stew ewar ards dshi hip p 3) Us Usin ing g so soun und d sc scie ienc ncee
The ecosystem concept is the heart of managing sustainability. When we try to safeguard species or manage living resource so that they are sustainable, we must focus on the ecosystem and make sure that it continues to function. The strategic goals and objectives of future coping mechanisms are to reduce unfavorable effects of climate change including variability and extreme events and promote sustainable development. Future coping strategies and mechanisms are suggested based on existing process and practices keeping main essence of adaptation science which is a process to adjust with adverse situation of climate change. Sharing knowledge and experiences of existing situation is a great way for stewardship. Development of techniques for transferring knowledge and experiences from one area/ecosystem is also necessary. If stewardship & application of
science doesn’t work together, it’s not possible to make future sustainable and restore state of equilibrium in ecosystem.
The End
