Population Growth 1 Lab 2. Previous workers (Smith et al., 2004) established a linear relationship between frond count and fresh weight (Eqn. Measure the surface area of your aquarium or pond. Topics: Photosynthesis, Lemna, Carbon dioxide Pages: 16 (3796 words) Published: February 22, 2012. The Effect of Fertilizer on Duckweed Growth by: Bri Benardin and Darien Ellis Discussion The control group steadily grew until it leveled out at and average of 65 fronds in the three cups. Research on using duckweed in the diets of domestic animals has been surprisingly scarce, perhaps because of the difficulties of growing sufficient duckweed under experimental conditions. In this experiment, the effect of acid rain on duckweed growth was tested. 7, No. Each experiment had at least six replications and at least three independent experiments were repeated to ensure validity of results. The detrimental effects of pathogenic bacteria on duckweed were quantified by two … The root is 1-2 centimeter long. Fresh weight and chlorophyll concentration quantification. Lower the tea strainer carefully into the pond. Experiment 1, "Dynamics of population growth: exponential and logistic growth" examines continuous population growth by growing duckweeds (Lemna spp.) Duckweed is the perfect space food: small, fast-growing and nutritious. About Duckweed (Lemna minor) ... two or three leaves each with a single root hanging in the water; as more leaves grow, the plants divide and become separate individuals. To be able to model this growth at these temperatures, an experiment is conducted with as goal; determining the death rate of duckweed at temperatures above 35°C. Duckweed strains that grew well on the swine wastewater were screened in laboratory and greenhouse experiments. 5. influence duckweed growth rate. Iran. Prior to all experiments excluding those investigating phosphate acclimation and nitrogen species, all experimental duckweed inoculums were maintained for a minimum of four days on 15 mg P/L (refreshed daily) before the start of each experiment. In doing this experiment we kept in mind the study of population growth and were interested in observing the different ways a population responds to different environments. Because of their impressive growth rate, they act as one of the best water purifiers that you can find for a fish tank and can be invaluable to newly established aquariums that are having water quality problems. Eng., 2010, Vol. A model or mathematical expression derived from duckweed growth data was used to fit data from experiments conducted in a greenhouse in Lubbock, Texas. Hypothesis: It is expected that the cup with the most amount of fertilizer (cup D) over the 14 days will have the most amount of growth compared to cup A, B and C. Apparatus: 4x polystyrene cups 20x duckweed fronds (5 in each cup) We dedicate more surface area of growing duckweed than to any other plant we grow. To conclude, the test system with L. gibba impaired by arsenic(V) was stable and reliable. Apparently, no observations were recorded on wastewaters at different salinity and so one cannot judge on the natural tolerance limits for the duckweed. The rates of nitrogen and phosphorus uptake by the duckweed growing in the laboratory and field systems were determined in the study. Measure the surface area of your tea strainer. Species of plant: Lemna minor L. was the only plant studied during the experiment so the growth patterns recorded were just for this species. In view of their rapid growth rates and ability to cover water surfaces very quickly, such studies are necessary, especially in sub-tropical countries, in order to develop viable management strategies. Experiment # Lemna minor (Duckweed) Population Growth . This experiment will investigate the effects of different concentrations of fertilizer on the growth of duckweed. The relationship between duckweed growth and the total nitrogen concentration in the mediium follows the Mitscherlich Function and is similar to that of other plants. Harini Santhanam [5] concluded that the Fuzzy quality index is bet-ter than Carlson’s trophic state index for trophic status analysis. The results and analysis were however not sufficient to construct an accurate dynamic model, but provided enough information to approximate the response at high temperatures. The selected duckweed strains were then tested for nutrient recovery under laboratory and field conditions. R. 2) was also established. The systematic negative control experiments did not yield any significant effects. It really is an amazing plant. This tiny organism is ideal for population growth experiments because it reproduces quickly, requires minimal space to grow, and requires no maintenance. Kaytlynn Martinez Bio 114 Duckweed Lab Report Introduction: The purpose of this experiment was to test the effects of sunlight on the population growth of Lemma minor, commonly known as duckweed.This factor is important because without sun, duckweed would not get the necessary food needed to grow, reproduce, and survive. 299-306 GROWTH, PHOTOSYNTHESIS AND RESPIRATORY RESPONSE TO COPPER IN LEMNA MINOR: A POTENTIAL USE OF DUCKWEED … It can be cultivated directly on the farm resulting in low production costs. We also predicted that carrying capacity would be lowest in the no nutrient treatment but equal in the other three treatments. Wait while the duckweed floats back over the strainer. Two separate experiments were conducted during the months of June and September, 2014 to investigate the nutrient (nitrogen and phosphorous) removal from leachate by growing duckweed… www.saps.org.uk 1. 2. The tiny floating plant adds nutrition to the diets of our fish and hens while purifying the water. It is hypothesized that altering the amount of light received by duckweed will alter its photosynthetic rate. Despite our love for the plant, most of the literature you will find online about duckweed is how to eradicate it. Experiment 2, "Resource limitation and population growth" examines the conditions that result in maximum population growth of Lemna by manipulating the resources that limit growth including nutrients, light, and surface area. This experiment has reviled one very significant result, and that is that in order for duckweed to grow not only fast but efficiently as well, the plant needs a high source of phosphate from where to get nourishment from, without the phosphate the geometric growth of the plant is noticeably slower. POPULATION GROWTH IN Lemna (Duckweed) A. Common duckweed (Lemna minor)By Walter Fertig. They are morphologically divergent members of the arum family Araceae.These rapidly growing plants have found uses as a model system for studies in community ecology, basic plant biology, ecotoxicology, and production of biopharmaceuticals, and as a source of animal feeds for agriculture and aquaculture. Field experiments on duckweeds, Lemna aequinoctialis, were carried out to determine the effect of plant characteristics on water-quality variables in ponds. 4. 3. At 5 d after treatments, samples were collected for fresh weight and chlorophyll analyses as described below. Given the same area one could produce more protein by switching to this little aquatic plant.” In the four-year project a multidisciplinary series of experiments will evaluate duckweed’s environmental and economic benefits. 1), and the relationship between fresh weight and dry weight (Eqn. Health. By studying how light levels changed the production of radiation-fighting antioxidants, researchers made it even better. Duckweed is a small aquatic plant that is able to grow rapidly, making it the ideal specimen for our experiment. Measuring Duckweed Begin by deciding how many samples of duckweed you will take from your aquarium or pond. Amount of nutrient solution: 200mL was the exact amount of solution that was poured into each petri dish. 2, pp. on duckweeds growth is summarized as duckweeds grow on a wide range of saline water and the observation of healthy duckweeds growth at a conductivity of 1460 µS/cm [2]. The average of 0.001 g/mL cups, the duckweed grew in the first couple of days, but leveled Sci. The amount of time they were allowed to grow: The experiment was planned to have duration of 28 days. experiments on Duckweed and found that Duckweed growth rate increased at a concentration of 1, 10 and 20 mg/l of Cd and Pb while a reduced growth rate was observed in 30 and 40 mg/l concentration. When starting this experiment, we hypothesized that systems with more nutrient availability would have an increased weekly growth rate and the high nutrient system would show the greatest growth rate. 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. It will disturb the duckweed. The purpose of this research project was to find just how harmful acid rain is to aquatic environments as it is starting to become a major issue in today's world. Growth characteristics—We measured the response of the duckweed to light in terms of the number of fronds as a function of time. is a member of the family Lemnaceae (duckweed family). It is predicted that a lower light intensity will lower the rate of growth in duckweed. “Duckweed’s protein content is good and so is its growth rate. Lemnaceae, or duckweed as it is commonly called, is a well-known organism that is ideal for biological experiments due to its easy maintenance, rapid reproduction rate and abundance (Kuhn, D., 1969). Experimental investigations have shown, that L. minor is able to completely replace the add-on of soy bean in the diet of ducks. The duckweeds (genus Lemna) and related genera of the duckweed family (Lemnaceae) are the smallest flowering plants known.Individual plants consist of a single, flat oval leaf (technically a modified stem) no more than ¼ of an inch long that floats on the surface of still-moving ponds, lakes, and sloughs. Lemna is a genus of free-floating aquatic plants referred to by the common name "duckweeds." The Duckweed Experiment: Effects of Lowering Light Intensity on the Rate of Per Capita Growth of Lemna Minor . The fertilizer requirements for growing duckweed depend on the water source and the geographic isolate of L. minor that is used. 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