Comparison of numbers of organisms In Coniferous And Deciduous Woodlands Essay Example

Comparison of numbers of organisms In Coniferous And Deciduous Woodlands Paper An experiment was done to find out whether there was a difference in the number of organisms in the coniferous and deciduous woodlands. A quadrat of 10m by 10m was used and co-ordinates 5,1 5,2 5,3 5,4 5,5 5,6 5,7 5,8 5,9 5,10 were used because these were exactly in the middle of the quadrat area. Ten samples of leaf litter and ten samples of humus was obtained from each woodland. In the laboratory tullgren funnels were set up, the samples were tested and the organisms were collected. A results table was made to record the numbers of organisms in. The results were displayed in graphs and tables. The graphs show the average number of each organism and the actual number of each organism in each of the woodlands. In the third graph five significant organisms have been picked out. This is because they have significant values and reasons for these values. The tullgren funnel was set up using a certain amount of the leaf litter that acted as a sieve that the organisms could fall through from the humus that was placed on top of the leaf litter. 20g of humus and 10g of leaf litter was used in the tullgren funnel because only a small amount was needed. A 100w bulb was used in both experiments (for each woodland). The organisms were driven, by the drying effect of the bulb, down the tullgren funnel and eventually they fell into the 30cm3 of ethanol. The organisms died but their bodies were preserved so that at the end of five days the different organisms in the ethanol and the larger organisms in the dried up leaf litter could be identified and recorded using a microscope and a dichotomous key. We will write a custom essay sample on Comparison of numbers of organisms In Coniferous And Deciduous Woodlands specifically for you for only $16.38 $13.9/page Order now We will write a custom essay sample on Comparison of numbers of organisms In Coniferous And Deciduous Woodlands specifically for you FOR ONLY $16.38 $13.9/page Hire Writer We will write a custom essay sample on Comparison of numbers of organisms In Coniferous And Deciduous Woodlands specifically for you FOR ONLY $16.38 $13.9/page Hire Writer This method was used because it was the most reliable, and ensured that all organisms present were removed from the sample in the tullgren funnel. Some very small organisms that were not affected by the drying effect of the bulb were not counted. During the experiment predation between organisms were occurring, this was not accounted for. The average test and the t-test were used, because two averages were being compared and there were less than 25 unmatched organisms in each sample. The value of t = 5.524 was greater than the value given for 22 points of freedom so that the Ho (null hypothesis) was rejected and the alternative hypothesis was accepted. Therefore the assumption, that the number of organisms are greater in the deciduous woodland, can be made. So the number of organisms did differ in the deciduous and coniferous woodland. The decomposition rate in the deciduous woodland is faster because organisms such as the earthworm can survive in this environment, because this environment is more alkaline than the coniferous woodland, which is more acidic. If conditions are less acidic then organisms such as the earthworm can survive and continue the fast decomposition, keeping the surrounding environment more alkaline. This is a negative feedback effect. So the number of species was greater deciduous woodland, with the exception of Springtails and small spiders. This is because these organisms have adapted to the acidic conditions of the coniferous woodland. Hypotheses Null Hypothesis (Ho) there was no difference in the number of organisms in the two soils. Alternative Hypothesis (H1) there was a difference in the number of organisms in the two soils. The Aim The aim of this investigation is to compare the difference in numbers of invertebrates in the coniferous and deciduous woodlands when samples are taken from each. The samples taken will be tested, recorded and evaluations will be made. Prediction The data collected will show that a coniferous woodland will contain fewer of the organisms that have been selected for study than in the deciduous woodland, and also that the depth of leaf litter will be considerably more in the coniferous woodland than in the deciduous woodland. Evidence In the deciduous woodland where the experiment was done, many different species of trees were growing. These trees have large, thin green leaves, to absorb the maximum amount of sunlight available. When these leaves fall off the trees to the ground, detritivores such as the worm, start the chain of decomposition. Without the detritivores the saprophytes (bacteria) cannot continue the process, after the detritivores, of breaking down the complicated organic matter. These leaves have a large surface area for detritivores to start the process of decomposition. Decomposition occurs relatively quickly therefore the layer of leaf litter will be thinner. However, in the coniferous woodland where the experiment took place there was only one species of tree and that was the pine. The pine needles are long and thin which are thought to increase the surface area for the absorption of sunlight. This surface area is also where, when the pine needles fall to the ground, the detritivores start the process of decomposition. Because of the conditions in the coniferous woodland the detritivores take longer to decompose the leaf litter. Therefore if the rate of decomposition is slow, and the rate of the pine needles falling are fast, then there will be more leaf litter on the ground of the coniferous woodland than on the floor of the deciduous woodland. The exotic conifer grows at a faster rate than the native broardleaves. Because the conifer is exotic, there are few insects and birds associated with it and so the exotic conifer is useless for use by native organisms. Because conifers are planted as a monoculture they are easy to manage (i.e. planting, weeding, fertilising, etc). But each tree needs exactly the same amount of nutrients and water because they are of the same species. This causes a deficiency of nutrients in the soil and so fertilisers have to be used. This could eventually lead to pest epidemics and so pesticides may also be needed. When a monoculture is planted, all the trees are of the same age and so are easily managed because there is little variation in height. The conifer woodlands and forests are planted in straight lines and are therefore easier to manage. However, this arrangement looks odd and unnatural because trees in a deciduous woodland are not planted in this way. If the conifers are planted densely then this ensures reduced side branch growth and increased height (therefore increasing the value of the timber). If all the trees are removed at the same time there will be a drastic change of the landscape which may result in a large amount of soil erosion. Variables * Light intensity in the coniferous woodland = 3.5 * Light intensity in the deciduous woodland = 3.5 * Temperature in the coniferous woodland = 28oC * Temperature in the deciduous woodland = 27oC Syllabus Areas Climate (i.e. local and micro climates, vegetation, landuse, topography). The Lithosphere (i.e. soils, nutrients, acidity). Ecological Relationships (i.e. ecosystems). Soil (i.e. conservation, cultivation techniques). Mathematical Skills (i.e. plotting graphs, understanding graphs, etc).

Cubism essays

Cubism essays Art before the twentieth century was recognized as an imitation of nature. Paintings and portraits were made to look as realistic and three-dimensional as possible, as if we are looking at the real object. The first cubist works were those in which objects, landscapes, and people are represented as many-sided solids. Artists were painting in a flamboyant style. Pablo Picasso (Spanish, 1882-1973) and Georges Braque (French, 1882-1963) initiated the movement when they followed the advice of Paul Cezanne, who in 1904 said artists should treat nature "in terms of the cylinder, the sphere and the cone." (art) In Cubism the subject matter is broken up, analyzed, and reassembled in an abstracted form. Cubism changed the way art was represented and viewed. There were three phases in the development of Cubism: Early Cubism, Analystical Cubism and Synthetic Cubism. It brought in new ways of composing pictures and also showed new ways of representing nature. This new movement also brought in new attitudes towards the picture surface and the application of paint. The ideas of colour theory were all changed. This caused a liberation of these elements from a merely descriptive function have all featured in the development of Cubism. The main distinguishing characteristic between cubism and other styles such as impressionism is that cubism does portray nature in art. Cubist painters are not limited to painting a certain color, or form, or a certain texture. Cubism broke objects down into basic shapes of cubes, spheres, cylinders, cones and line thickness. The shapes are flattened onto canvas so th at different sides of each shape can be shown simultaneously from many angles. This resulted in strong geometric patterns and angles. The style was described as being able to show objects in multiple viewpoints. The first stage, Early Cubism, was characterized by the simplification, distortion, and emphasis of the forms of objects. It consisted of fac...

Roosevelt Corollary and Monroe Doctrine Essay Example | Topics and Well Written Essays - 750 words

Roosevelt Corollary and Monroe Doctrine - Essay Example Although the US would be neutral in any war between European countries and their colonies, any action happening on American soil would be viewed as hostile. The Roosevelt Corollary to this doctrine was added during the presidency of Theodore Roosevelt, during the Cold War, ostensibly to combat the Russian Communist influence. Roosevelt asserted the right to militarily intervene in the Caribbean, Central America and in Latin America. Although it was initially seen as a step taken by the US to morally oppose Colonialism, Roosevelt completely turned the Doctrine on its head, by reinterpreting it as a right to intervene in the economic affairs of smaller/ less powerful nations if they were unable to pay their foreign debts. This was also referred to as the Big Stick Policy, especially by the media and in cartoons. (Spiritus-Temporis.com, 2005) Early during Roosevelt's tenure, when Venezuela defaulted on loan repayments to Great Britain, Italy and Germany, they erected a blockade to fire upon Venezuelan coastal fortifications. This led to Roosevelt's retaliation, and he succeeded in driving out the Germans and all other European interests from Venezuelan waters. From this incident, the US became more and more ambitious, resulting in interventions in Cuba, Nicaragua, Haiti and the Dominican Republic. There were also attempts at assassination of foreign political leaders, who refused to toe the line. (Spiritus-Temporis.com, 2005) Subsequently, t... The US has used its veto power in the UNO, and influential position in world bodies like the World Bank, the IMF and the WTO to economically gain control over the weaker economies of the Third World. In the guise of bringing about fairness and equality in international trade, the US has forced weaker countries to break down trade barriers, so that it could have entry into their markets. It has cannily used the IMF to forward its interests. When the IMF gives loans to developing economies, and in case they default on these, terms and conditions of these agreements force these nations to accept economic and trade practices that are detrimental to them. (Tyehimba, 2004) Even in the case of the Iraq war, it is common knowledge that the war was waged as an attempt to gain control over Iraqi oil. No traces of weapons of mass destruction were found, although this was given as the reason for going to war. (Tyehimba, 2004) As a matter of fact, the cause of the unfortunate 9/11 incident may be traced to the US itself. The incident is unpardonable, and the perpetrators deserving of stringent punishment; but the reason for events having come to such a pass is the US' cold and calculating exploitation of poorer nations. Unfortunately today there is violent opposition between Islamic interests and the West, destabilising life for everyone. We have slid back into the era of the Crusades, and it is difficult to see whether various countries and religious groups will ever be able to co-exist peacefully. All this is a consequence of expansionist US foreign policy, which has its roots in the Roosevelt Corollary to the Munroe Doctrine. Works Cited Spiritus-Temporis.com, The Roosevelt Corollary, 2005, , retrieved 26th July,