Identifying the Food Web in the Experimental Ecosystem - Term Paper Example

Ecosystem Student’s Name: Instructor’s Name: Course Code & Name: Date of Submission: Abstract The following report presents an experiment done with an aim of identifying the food web in an aquatic ecosystem... The ecosystem consists of two snails and some aquatic vegetation. The experimental period is two weeks. There organisms in the experimental setup are monitored after which conclusions are made. Introduction An ecosystem is a community of living and non living things co-existing together. An ecosystem comprises of plants and animals and non living things in the environment for instance soil and minerals. Every component of an ecosystem is important; since has its own specific role to play hence leading to an ecological balance. One of the best ways of explaining the importance of every component in an ecosystem is the food chain/ food web. Precisely, each organism in an ecosystem gets its food from the ecosystem in which it exists in. For this reason, a natural or manmade interference with an ecosystem leads to an ecological imbalance; which is one of the reasons as to why several organisms have become extinct as per the evolution theory. There are basically two types of ecosystems which are terrestrial and aquatic ecosystems. Terrestrial ecosystems are for organisms which live on land while aquatic ecosystems are for organisms which live in water. However, there is a middle ecosystem between the two; that is an integral of aquatic and terrestrial ecosystem on which such organisms as amphibians live in. the following report will focus on purely of aquatic ecosystems (Eco Systems. Org, 2012. P1). Aquatic ecosystems are divided into two; freshwater and marine ecosystems. As the names depict of the ecosystems, the difference between the two ecosystems is fresh water and salty water (U.S. Environmental Protection Agency, 2012, p.1). In each of this two types of ecosystems, there exists various sub ecosystems, each of which have varying characteristics. Under marine ecosystems, there is oceanic, intertidal, estuaries, coral reefs, benthic, profundal, and hydrothermal vents. Under freshwater ecosystem, there is lentic, wetlands and lotic ((Eco Systems. Org, 2012. P1). This report is about an experiment which was conducted on an aquatic ecosystem, ‘the bottle experiment’. The experimental ecosystem is a lentic ecosystem since the water is still. In the experiment, the ecosystem is monitored is a period of three weeks. The growth behavior of the organisms in the experiment is monitored over the period specified above. Aim of The experiment The aim of the experiment is to identify the food web in the experimental ecosystem. Hypothesis The snail is dependent on the algae for food. The Snail is the primary consumer The algae are the primary producers. The snail and the algae are interdependent on each other, each one of them depends on each other for survival. Materials and Methods The materials used in the experiment include the following: Snail Sediments (weight 430.51g) Lemma (weight 0.86g) Algae & Nitella (weight 0.264g) Mayfly (length 0.6 cm) Water (1.6 liters) Transparent water jar (square base with 12.5 cm width, 21 cm height). The method for carrying out the experiment The jar was cleaned so as to remove any foreign materials and also to increase its transparency. It was then filled with fresh water, (7.2 ph level). This was in order to create an aquatic environment for the experiment. After this, sediments weighting 430.51 grams were added to the jar. The sediments were added in order to create an aquatic environment. They accounted for the non living elements making the experimental ecosystem. After this, Lemma weighting 0.86g., Algae & Nitella weighting 0.264g. and Mayfly of length 0.6 cm. were placed to water in the jar. The aquatic vegetation (duckweed) is the primary producer in this ecosystem. In addition to this, the aquatic plants have varying roles to play in the ecosystem. Lastly, the experiment setup was placed in the laboratory conditions, with appropriate sunlight and other atmospheric elements so as to provide a typical aquatic ecosystem. The growth behavior of the organisms, the state of the water (PH, water NO3, water PO2- electro conductivity and temperature) was monitored and recorded. Results The observations were tabulated so as to make them more presentable. The following table presents the results. Table 1: The Results Element / organism in the ecosystem Initial measurements 1st Week 2nd week Water PH NO3 PO2- Electro- Conductivity Temperature Color 7.2 0.00 mg/l 0.75 mg/l 1.2 20.6o c Transparent 9.9 0.00 mg/l 0.25 mg/l 0.7 24.2o c Pale Green 10.2 0.00 mg/l 0.25 mg/l 0.7 280 c Less clear, greener Snail 1 Height Width Weight Snail 2 Height Width Weight 1.0 cm 1.6 cm 1.96 g 1.5 cm 1cm 1.3g 1.5cm 1.8 cm 2.5 cm 1.9 cm 1.3 cm 1.6cm 2.6 cm 2.0 cm 3.6 cm 3.0 cm 1.6 cm 2.5 cm Algae &Nitella 0.26 cm Coverage 0% Algae Spreading Nitella coverage 0% Mayfly 1 Length Mayfly 2 Length 0.6cm 0.8 cm No sign of both of them No sign of both of them Lemma 0.86 g Coverage 1.5% Coverage 20% Sediments 430.51g - 431.0 From the table below, the following inferences can be made: The mayflies vanished from the ecosystem. This is because the ecosystem did not support their survival. The snails grew over the two weeks. The snails enjoyed their stay in the jars. They developed with respect to their body sizes. Both of them had a significant growth in height, width and weight (Wahl, M., 1996,p.160). The algae were increasing its coverage in the jar. After the two weeks of experiment, the algae were spreading. On the other hand, nitella had vanished from the ecosystem. Lemma was also growing. Over the two weeks of the experiment, lemma had increased its coverage in the jar to 20%. The sediments in the jar had also increased in weight. At the end of the experiment, the sediments were dried and weighed. It was realized that their weight had increased. This is due to the waste from the snails and the other organisms in the ecosystem. The water had also had a substantial change. Firstly, its color had changed tremendously. The water was slowly turning greenish. This is due to the increased area coverage by the algae and the lemma. The PH level of the water had also increased over the experimental time. The PO2-4 levels in the water had also reduced. The Nitrogen amount in the water remained zero. The temperature of the water also increased over the experimental period (Lake, M, Hicks, B., Wells, R., & Dugdale, T., 2002, p 16). Discussion From the experiment, the following web chain can be identified. Food Web Taking a look at the experimental ecosystem and the observations made thereafter, the following can be deduced: the algae, the lemma and the nitella are the primary producers in the ecosystem. They provide food to the snails and the mayflies. This follows the basis ecological rule that vegetation is supposed to provide food to primary consumers. The recorded growth on the snails is as a result of their feeding on the aquatic plants introduced in the experimental ecosystem (as shown in graph 1). In addition to this, the aquatic plants purify the water in the ecosystem. As a result of this, the water is purified. Therefore, the snail is dependent on the aquatic vegetation for food and also a conducive living environment (Okon, B., Ibom, L, 2012, p.146). On the other hand, mayfly is not observable in the jar. This is because the ecosystem is not conducive for mayfly to survive in. as a result of this, it died away. The Ph of the water is rising because of the presence of acidic metals which tend to increase the acidity level of the water. The vanishing of nitella from the experimental ecosystem results to a lack of the regulation of the PH levels of the water. This leads to the gradual increase in the PH. The temperature of the water rises due to the increased metabolic rate of the snails (Akhavan, M., 2011, p. 35). This leads to a lot of heat energy being evolved from their bodies, resulting to arise in temperatures. The increased vegetation coverage on the water also acts as an insulator, hence preventing heat losses out of the water. This is illustrated well in the graph 2. The aquatic vegetation needs carbon 4 oxides for photosynthesis which is readily provided by the snails. On the other hand, the vegetation provides oxygen to the water. After the oxygen dissolves in the water, it is used by the snails for respiration. This explains why the coverage of the vegetation increases as shown in graph 3. The electro conductivity of the water is reducing due to the reduced presence of free phosphate ions. Conclusion In conclusion, it is evident from the experiment that a food wed is very important in an ecosystem. As identified earlier, every organism in an ecosystem is important. The survival of the snails is dependent on the availability of food, and the availability of optimum environmental condition s which are provided by the aquatic vegetation. In a typical food web, the snail provides food to other animals for example turtles and humans.. For this reason, there are mutual benefits between the vegetation and the snails, which explain why each one of them has grown over the experimental period. References Akhavan, M., 2011. Effect of PH and Heavy Metal Concetration on Photoaccumulation of Zinc by Three Duckweeds Species, American Eurasian Journal of Agriculture and Environmental Sciences. Vol. 10. No. 1; 34-41 Eco Ststems. Org, 2012. Different Types of Ecosystems, Viewed on 7th October from Lake, M, Hicks, B., Wells, R., & Dugdale, T., 2002. Consumption Of Submerged Aquatic Macrophytes By Rudd (ScardiniusErythrophthalmus L.) In New Zealand, Hydrobiologia Vol.470, no. 1; 13–22. Okon, B., Ibom, L, 2012. Evaluation of Growth and Correlations Between Body Weight and Shell Measurements of the Juveniles of Two Ectotypes of Archachatina marginata var. Saturalis (P) Snail, International Journal of Agriculture and Forestry, Vol. 2, no.4; 145-149 U.S. Environmental Protection Agency, 2012. Marine Ecosystems, Viewed on 7th October from Wahl, M., 1996. Fouled snails in flow: potential of epibionts on Littorina littorea to increase drag and reduce snail growth rates, Marine Ecology Series, Vol. 138, no. 1; 157-168 Graphs Graph 1 the growth of snails, (weight) Snail 1 Snail 2 Temperature increase in water graph 2 Temperature increase graph i PH increase Graph ii Vegetation coverage graphs 3 Lemma graph i Algae graph ii Read More