We hypothesized that the carrying capacity would reach the peak when the duckweed was being exposed to natural light over the red and blue light because natural light incorporates all the colors. Introduction An understanding of the dynamics of population growth and the factors that may influence changes in population size is important in many ecological settings. %PDF-1.5 %���� Measuring Duckweed Begin by deciding how many samples of duckweed you will take from your aquarium or pond. It is predicted that a lower light intensity will lower the rate of growth in duckweed. The duckweed was placed in stagnant water which contributes to the growth of the duckweed as this is a more favourable condition for duckweed growth (John W. Cross, 1998-2002). For Cu concentration of 0. Materials Duckweed fronds, 16 Dissecting needle or forceps Fertilizer, liquid Graduated cylinder, 25-mL Potting soil Marker or wax … Measure the surface area of your tea strainer. the population no longer grows). endstream endobj 176 0 obj <>stream Lower the tea strainer carefully into the pond. The plant reproduces by vegetative budding, although it may flower. Growth rates were four-fold higher for Tilapia supplemented with duckweed compared with Taro leaves or no supplement; and were 22% higher in ponds fertilized with biodigester effluent compared with no fertilizer . Introduction Duckweed is an aquatic plant used often in removing some nitrates from water. W��:�B�\3����5� In Part B the magnitude of interaction is explored by growing monocultures and mixed … By studying how light levels changed the production of radiation-fighting antioxidants, researchers made it even better. Cup D was shown to have the highest growth rate, which was expected, as it has the highest concentration of fertilizer thus providing the most nutrition. )@H� B���X��ʂT�����b;;� �� Duckweed are useful plants for students to use to develop investigations. Check all that apply. Duckweed prefers slow moving water however, you will notice fastest growth with areas of agitation. �9;�B�S�;%e3 �"�`LQ� h޼Zmo�8�+�K��Z|9,�M�f��;4���>��� �K�6y��c��ǚ:L0y�\r��y�R�9G �X�q��o�4����ۥϕ�Va�J�@�����'E3R�`O h�22W0P���w�/�+Q0���L)�66 "Sunlight is broken up into a prism of light, … DOCX, PDF, TXT or read online from Scribd, 0% found this document useful, Mark this document as useful, 0% found this document not useful, Mark this document as not useful, Duckweed is an aquatic plant used often in removing some nitrates, left in natural light for a week will yield, natural light which was near the window, high light on a, * There could be a confounding variable with the s, counted out twenty-five duckweed frons and put that amount in each, natural light, low light). Different wavelengths of visible light appear as different colors. After a week had passed the results were as follows: Before we conducted our experiment, we hypothesized that the natural light, environment would be the best place for fond growth. It is hypothesized that altering the amount of light received by duckweed will alter its photosynthetic rate. It is hypothesized that altering the amount of light received by duckweed will alter its photosynthetic rate. Below 17 °C some duckweeds show a decreasing rate of growth. A dense cover of duckweed inhibits competing submerged aquatic plants, which require solar energy for growth and they can also often exclude algae from bodies of water. Also, the effect of plant growth on the removal efficiencies of cer- tain pollutants was investigated. Anong Phewnil et al., concluded that the growth rate ofLemna Perpusilla Torr. … Duckweed is a small aquatic plant that is able to grow rapidly, making it the ideal specimen for our experiment. Measure the surface area of your aquarium or pond. Duckweed growth is optimum at temperatures between 20 and 30 °C, but serious effects will occur at temperatures between 35 and 40 °C. 2 mg/L was considered as the threshold toxicity in Lemna … However, as time passes, the rate of growth s hould slow and approach zero (i.e. #! The free-floating, freshwater plant consists of a green elliptical frond with one root and is found in still waters, from temperate to tropical zones. The average of 0.001 g/mL cups, the duckweed grew in the first couple of days, but leveled POPULATION GROWTH IN Lemna (Duckweed) A. Duckweed’s fast growth rate allowed us to conduct a two week long experiment to test if these factors manipulate duckweed growth rate. 175 0 obj <>stream The lack of dissolved oxygen in water bodies, through its uptake by microbes for decomposition of organic compounds, produces degrees of anaerobiosis that results in m… The duckweed divide quicker. 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