ECOLOGI\ CAL ; SSE ere SSeeeeeee CEP Seere ere Cee Seeeeeereeereeeee TMBALANCE nn Invasive species Invasive species are plants or animals which have moved to a habitat where they were not. naturally found and are more successful than local species. 7Pollution Our oceans, rivers, lakes and lands have become rubbish bins for society's industrial and organic waste, “Habitat loss Agriculture, housing and industry are destroying the habitats of many plants, animats and microbes, ? Exploitation An Asian ladybird, the We have drastically reduced Harlequin, was first spotted in some fish populations, hunted ‘the UK in September 2004 some whales to the verge of and has now spread extinction and destroyed throughout the south-east. _ whole forests and thelr This voracious species out- ecosystems ‘competes our native ladybirds Climate change for food, and will even eat Many plant and animal them when other food is species are unilkely to survive short. Sclentists are climate change. For some concerned that our native species there will no longer be ‘species could be wiped out. anywhere to live, The Tiger Moth has declined by 44% In the last 30 years. Scientists believe this is linked to climate change~ N eo CAUSES OF ECOLOGICAL IMBALANCE Causes 2 eee * 9) Habitat doxbuction a encroaches | One of the biggest threats to blodiversty is habitat destruction or encroachment. Our constant development means that we must destroy fuatural econystems im the name of progress. Sometimes our development does not destroy an ecorystem but slmply decreases lis size, This in itself ean be destructive, Many animals have a certain range that they must maintain inorder olive, Ifthey do not have access to tis area, thelr lives are sgnficantly altered. Closer quarters enuses ‘more competion between speces, and this may lead tothe eventual txtinetion of one or more species. See Development for alternate A methods of building, Constal re developed as vacation areas or as simply areas of sprawl for large elties. When this occurs, the oceans are affected, along with all the life in them.. See Terrestrial Ecosystems for more details on probleme affecting these transition zones, Blast fishing is practiced In many areas. This is the process whereby dynamite Is placed into an area in order to catch a large quantity of fish. Coral reefs especially are devastated by this activity. It ts most prominent In undeveloped count where ls practice has existed for years, SOLID WASTE lc In our garbage causes enormous problems. It kills or injures ‘many marine animals and birds elther throujean ‘The greenhouse effect will be accelerated as rain forests are decimated. The forest large ‘quantlties of water from the soll (o the alr throagh evapotranspiration. As the earth warms In greenhouse predictions, the rate of this process will increase. Therefore, cloud production will Increase and ald tn reducing the surface temperature. While this is a positive effect, the more trees whch are cut, the more nature's capacity (o malataln this temperature Is lost, The greenhouse ‘effect will increase dramatically as the forests dwindle (Thorne-Miller and Catena 10). See the page ‘on Greenhouse Effect for more detalls. ‘OTHER PROBLEMS A) caning ata razras Rong eon dm em eine nr haa produce ee | Overharvesting of speeific spectes 7 ©)_/ GREENHOUSE EFFECT Oversharvesting of certain speetes Is occurrin alarming rate, Yet, unlike with domesticated animals which are bred for consumption, these species are f being replenished. With the fishing techniques we ha ble to us now, the fish have litle chance of evading eapture, We have sophisticated electronic equipment which ean find fish that previously could avoid us. In addition, we have a multitude of nets and other means of catching the animals that are so widespread and omniprese there is nowhere for the fish to hide. ©) Pesticide ve and cunoft -f)Pentetne nutrient in the aol due to poor farming technics, 1) mantputation oF stock ‘The number and types of animals grazing an area should be carefully considered based on the resources available in the region. After the animals are introduced to the area, grazing must be controlled so that ‘the animals range uniformly over a large area and do not destroy one section. If animals are allowed to ‘graze one arca continuously, they will overgraze it. Strategic positioning of salt blocks can be used to induce animals to go through areas that they ds lly graze in order to reach a water source (Owen etal. 330).a Overgrazing also causes problems for our livestock. The most nutritious plants will be eaten first, leaving only those with littl nutritional value forthe herd, ‘To avoid this, pastures can be fenced off, Leaving only specific areas open for grazing at aly one time. One example ofthis isto use an area one -year, then bar access to ths area the next year. By rotating stock to different pastures all ofthe pastures ‘will have time to recover from the pressures of grazing. This type of planning will benefit both the grasses. and the underlying soil {Ramune emacrces Erosion has also become a major problem on our farms. Because our fields are never given a chance to Tecover between growing seasons, much of our soil is simply eroded away. This erosion often causes problems far away from the source. Many water sources become filled with sediments to the extent that they become unfit as habitats for aquatic species. In addition, too much sediment in the water ‘auses us problems when we have to treat the water further before it ean be used for human consumption, Another problem with our farming practices is the use of pesticides and fertilizers to ensure more Productivity of our crops. The costs of farming are quite high, and itis natural or farmers to. want to obtain the largest harvest they can to offtet their oper- ating expenses. However, the pesticides which we use on our erops harm more than just the intended pest species we hope to kill, They are washed away in the rain into our groundwater sources and eventually into our rivers and oceans. These toxins are deadly to many species of enimals and fish, (Q, )Overpopuiation and the need for and for food and habiat In 1996 there was a 15 person per thousand net incresse in global population (1.5%). Most of {his increase is in less developed countries (Owen etal. 69). The doubling time Is tte tine required for a population to double Mts size. Based on the 1996 population increase figures, it would take 45 Years (from that year) to double the earth’s population. If the population rate continues unchecked, in the year 2041 we will have twice the number of people on earth as we did in 1996. This isan astounding prediction. Effects of Population Growth 1) More garbage (especially solid waste). 2) More alr pollution from factories as they Increase produc tton to meet demand. 3) Depletion of energy resources as the demand for increases, 4) More pesticide use as agriculture Increases to provide necessary food. 5) Accelerated loss of nutrients In the soll due to poor farm- {ng practices and overuse of land. 6) Habitat destruction for wildiffe through encroachment on wilderness areas or pollution of these areas. ergy ‘These are only s few of the negative consequences caused by averpopulation of the planet, Others are more subtle and are socially orie socletles (or even citles within a dy there are debates between countries over wateraay resources. In the United States alone, states are competing for the rights to water sources for thelr Inhabitants. These types of problems will only increase over the years. ‘There is now the threat of mining the seabed for minerals as we run tow on these resources on land. ‘There is also talk of burying toxic waste at sea, Due to the dispersal quallty of water, the toxins ‘would spread for miles, Ww ha Ecological batanen sr naeersary - To understand why ifs loss is important, you must first know what biodiversity is. The generic definition is the number of species in an enviroriment and the numberof individuals in each species. To put it simply, itis the number of different species in one area and the quantity ofeach oftheve species. Newer definitions include genetic variation within a species and variations between types of biologi ‘communities on the earth. Functional diversity is also now studied. This is an alysis of the biological functions performed by a specific ecosystem. This is useful in deter- mining the ‘consequences of human impact on an area. However, this is difficult to measure; and itis highly possible that important functions of an ecosystem may be overlooked in this measurement due to our ignorance of the processes involved (Thorne-Miiller and Catena 9). ‘The fimetioning of the biosphere (or our entire planet) is dependent on the combination of al ex ecosystems. Our very existence depends on this process functioning properly, Every organism has its niche in the environment. Once itis gone, it may not be able to be replaced by any other organism. What does this mean for us as humans? A whole host of things. First, loss of diversity in an ecosystem can cause environmental changes. Loss of one species may cause a chain reaction, resulting in a change to the ecosystem itself. As we do not know what each specific ‘organism contributes to its environment, we cannot predict how the ecosystem will be affected, ‘The whole -ecosystem may be weakened by this process. Plants and animals produce defense mechanisms which are often chemicals used to either repel predators or to sid in elimination of their competition. These chemicals ae vitally important to humans because many cures for human diseases have been found in these compounds. Ifa species is last due to our interference {nits ecosystem, we also lose the ability to study it for possible benefits to mankind. ‘Secondly, the loss of diversity gives us less choice as humans. This involves several areas. If cor species are lost, they are no longer available to us ether as food, as enjoyment, or as resources for things we may not even know about yet. For example, if we deplete all the yellowfin tuna inthe ocean, we no longer have this species available for our consumption. If we are divers or underwater explorers, We NO longer can see this fish in its own environment and receive pleasure from this act. ‘The fewer animats left, the fewer we ean see when we interact with nature Other problems with loss of diversity are’ more: few organisms left the genetic diversity ith species is depleted so that there are only awre the species. IFall the individuals left are weak, have some form of abnormality, or are unable to survive in their environment, the species is doomed to extinction, Extinction isa natural process that has occurred for millions of years. The problem is that the rate of extinction has increased dramatically in tecent years due to our impact as humans. The rate of change is perhaps as damaging as the effects of the changes, There is no time for organisms to adapt to their constantly-changing environment. ‘One species may be necessary for the survival of another species. I'an animal or plant is the main or only food source for another, its extinction will cause a domino effect. Other species will die out after the ‘original one is lost. ‘The oceans of the world are much more stable than the land. Changes here usually take a long time. The ‘organisms which live here have adapted to meet this slow, gradual change, They cannot tolerate drastic, abrupt changes. Loss of diversity in an ecosystem can cause environmental changes. Loss of one species may cause a chain reaction, resulling in a change e to the ecosystem itsell. Every organism has its niche in the eanerar Jenvironment. Once itis gone, it may not be able to be replaced by F a Jany other organism. As we do not know what each specifi lorganism contributes to its environment, we cannot predict how the ecosystem will be affected, The whole ecosystem may be weakened by Ea this process. WEROREION i {23% A second important consideration is that pls ind animals produce i s18|defense mechanisms. These are often chemicals used to either repel ! [predators orto aid in elimination of thelr competition. These eee pa ichemleals are vitally important to humans because many cures for Syacotcmat HENEETTS human diseases have been found in these compounds. Ita species is ‘lot due to our interference in it econystem, we also lose the ability fo | | study for possible Benes to mankind oce Terrestrial Ecorytems Fo Mocm ec Complex relationship between three keystone species th sea tte, theses urchin, sna tat {i any on ot een dsr eysront srecies +) population, the whole ecosystem Is changed. The otters keeps the uurehin population in check. Without them, the urchins would devour |: the whole kelp forest. The kelp provides homes for many other & wey organisms which would suffer if lt was destroyed. Yet, without sufficient sea urchins, the sen ‘otter population would decline. It 1s a complex web which must be balanced Properly for the system to thrive (Thorne-Miller and Catena 24-25),‘An aspect not given much thought thatthe Lose of diverdiy vee Ae ‘An Per ciaz humans, Uf certain species are lat they ars no ong fs Boer te. \ wa table to us either as food, as enjoyment, or as resources (oy things ike ee: 1 ara ot even know about yet. For example, if we deplete al te PERS igs Sieh tuna the ocean, we mo longer have hi speies syalehle J Jato sumption. Ifwe are divers or underwater explorers, we eeonger can ave this fish in its own environment 2 nee cpteaaure from this nct. We also no longer have the sbulty rae scaly this species to ave how it interacts with oer species 18 is ‘ecosystem. ‘Other problems with loss of diversity are more subtle, When © species Is depleted so that there are ny fee arganism left, the gentle diversity inthe species Decors et low. All future offspring only a few oruaen ofthese fet individuals, This Towers the survival ate of ‘the species by decreasing ana cov of Denefila genes inthe population. Tal the individuals fet fare weak, have some form te cee, or are unable to survive in thelr environment, the species * doomed to extinction. ‘A tnundred years ago a whaling ship could eapture ‘3ed0 whales in one three-year trip, Yet, in the 20h ‘century atthe peak of Indus- : trial whaling, the same amount of whales” w processed in two weeks (Cousteas 215).. This has Pinsed the collapse of whale populations...) SMoridwide. Some are very near extinction, The Taternational Whaling Commission has impor, | Hunts on whale hunting, and some species are slowly/ seen from our acta: However, asthe species) ‘count rises again, countries sre perched o| Gn the brink ready to lift the ban on, whaling af the. | first moment : that they possibly can, Jf this ie done, our efforts will fre beca in vain for it will take very few years for" sme scenario where we found”) al systems ald humans ts that they can be ‘When an ecosystem 1s disrupted and other Anot foreegiterd of the Cuttings CE + CENTR, 4 Larne } “ SZ SexNO®.