VEGETATION ANALYSIS LAB REPORT
INTRODUCTION
Growth in plant may be referred to as a progressive development in plant and can be expressed in terms of dry weight, length, diameter, and height. The growth of the plant results in the development of different structures, which all the conditions are optimum results in a proportionally matured plant. Agents that affect plant growth may be classified as environmental or genetic. Environmental factors affecting plant growth include the content of the moisture in the soil, temperature, radiations from the sun, soil reaction, mineral nutrients that are available, biotic factors and atmospheric composition among others. Each of these factors may be a limiting factor in the growth of the plant, and their effect is dependent on the availability of the other environmental factors. Temperature for instance affects the rate at which different processes in plant take place. Some of these processes include respiration, photosynthesis, water and mineral absorption, and transpiration. Most of these processes increase with an increase in temperature although the increase rate differs from one plant to another. The intensity, quality and duration of light intensity are very important variables in the growth of a plant. Good quality of light ensures that the process of photosynthesis is optimum. The duration of light determines the amount of food that is synthesized by the plant where those plants that have adequate light produce enough food for growth while those that receive excessive light have their tissues destroyed by the light. Low light intensity of duration may result in abnormal growth of the plant where the plants that are in the areas where the intensity of light is a low end up becoming very long with an aim of accessing light. The question that this experiment aims to answered is whether low light intensity has an impact on the height of the plant. It is hypothesized that leaves in low light intensity areas have a larger surface area compared to those in areas with high light intensity.
The experiment involved collection of common olive leaves from the school compound. The leaves that were picked were those that were found growing either in low sunlight and high sunlight conditions. The Common Olive trees were located in the compound and the leaves picked by hand from the middle of the branch. A total of six leaves per condition were collected. Once the leaves were collected, the samples were taken to the laboratory where they were drawn on a paper. The papers were cut in a similar shape as the leaves and the surface area of the paper measured to represent the surface area of the leaf. The data collected was recorded.
RESULTS
Results for two different experiments were recorded as shown in Table 1 below. On average, those leaves that were growing in high sunlight conditions had a lower surface area compared to the leaves that grew in low sunlight conditions.
A comparison of the average surface area of the two different kinds of leaves is as shown in Figure 1 below.
Figure 1: The bar graph comparing the two averages of Common Olive leaf surface area (found in low and high sunlight conditions)
DISCUSSION
The experiment aimed to determine the effect of environmental factors (sunlight intensity) in the growth of plants. The obtained results have shown that exposure to low sunlight results in leaves with a large surface area while high sunlight results in leaves with a smaller surface area. The large surface area in leaves may be an adaptive measure to increase the number of chloroplasts in the leaf and hence an increased rate of light absorption. This enables the leaves living in low sunlight conditions to have an equal capability to synthesize food just like those leaves that are in the high sunlight condition. The obtained data supported the hypothesis that leaves in low light intensity areas have a larger surface area compared to those in areas with high light intensity. The leaves in high sunlight gave an average of 464mm2 while the leaves in low sunlight condition gave an average surface area of 500mm2. The variations witnessed in the data may have occurred as a result of defining low sunlight and high sunlight conditions poorly. The error did not, however, affect the results since the experimental outcome. In some instances, leaves with a low surface area of 285mm2 were classified in the low sunlight condition while others with a surface area of 729mm2 were classified in the high sunlight condition. To better understand the effect of such factors in plant growth, a laboratory experiment where plants are subjected to the different conditions is recommended. Investigation of the effect of other environmental factors such as temperature is also recommended.
