Population Growth Density Dependent Factors Abstract...

Population Growth: Density dependent factors Abstract Sets of experiments were used to assess the growth rate of the Lemna minor, a duckweed population. The growth of Lemna minor was observed and followed by counting and recording the number of thalli on a weekly basis. These experiments were constructed lab models which varied the size of the starting thalli population, and varied the nutrient concentration the thali were placed in. In the first experimental model two plastic cups were prepared with pond water, then two healthy lemna minor plants were placed in the first cup while fifteen healthy lemna minor plants were placed in the second cup. The second experimental model consisted of four nutrient concentrations, a control model of no nutrients, a low nutrient model, a medium nutrient model and a high nutrient model. At high density populations, we observed a nonlinear decreasing growth rate with increasing lemna minor density. At very low densities, as expected, we observed an inverse density dependence. Duckweed reproduces by budding, causing a larger density to reproduce a greater amount of biomass. This would indicate that Duckweed likes overcrowding, and this may be a possible clue to the limiting factor in the growth of Duckweed. Introduction Lemna minor, commonly known as duckweed, is efficient and fast growing, making it an ideal experimental organism. It is known as a small aquatic monocotyledon which can be found floating in ponds, lakes or streams (Harper,Show MoreRelatedThe Effects of Population Density on the Reproduction and Survival of Daphnia Magna2308 Words   |  10 PagesAbstract The population dynamics of Daphnia magna are observed under three different conditions; low, medium, and high density. The effects of different population densities on the survivorship and reproduction of Daphnia are observed over a two-week period within a lab environment. Over the two week period, the numbers of parent Daphnia alive and dead are recorded daily, along with the amount of offspring produced each day. From the main parameter investigated, the net reproductive rate, theRead MoreInstitutions as a Fundamental Cause of Long-Run14323 Words   |  58 PagesAS A FUNDAMENTAL CAUSE OF LONG-RUN GROWTH DARON ACEMOGLU 1 , Department of Economics, MIT, 50 Memorial Drive E52-3806, Cambridge, MA 02142 e-mail: damn@mit.edu SIMON JOHNSON Sloan School o f h f a ~ g e m e n t , MIT, 50 Memorial Drive, Cambridge, MA 02142 e-mail: sjohnson@mit.edu JAMES A. ROBINSON Deparhnent of Government, WCFIA, Harvard University, 1033 Massachusetts Avenue, Cambridge, MA 02138 e-mail: jmbinson@gov.harvard.edu Contents Abstract Keywords 1. Introduction 1.1. TheRead MoreGlobal Climate Change : A Threat Of Aphid Populations Essay8320 Words   |  34 PagesClimate Change: A Threat to Aphid Populations Abstract Global climate change is a matter of grave concern in the present scenario casting its significant and lasting effect on the flora and fauna dwelling over earth. A number of factors such as biotic processes, variations in solar radiation received by earth, plate tectonics, volcanic eruptions certain human activities can be considered as key components responsible for this devastating phenomenon. Aphid populations are also under potential threatRead MoreNihms4511 Words   |  19 PagesNational Institutes of Health, Bethesda, Maryland, 20892–4442, USA. Abstract $watermark-text The skin is the human body’s largest organ, colonized by a diverse milieu of microorganisms, most of which are harmless or even beneficial to their host. Colonization is driven by the ecology of the skin surface, which is highly variable depending on topographical location, endogenous host factors and exogenous environmental factors. The cutaneous innate and adaptive immune responses can modulateRead MoreInstitution as the Fundamental Cause of Long Tern Growth39832 Words   |  160 PagesNBER WORKING PAPER SERIES INSTITUTIONS AS THE FUNDAMENTAL CAUSE OF LONG-RUN GROWTH Daron Acemoglu Simon Johnson James Robinson Working Paper 10481 http://www.nber.org/papers/w10481 NATIONAL BUREAU OF ECONOMIC RESEARCH 1050 Massachusetts Avenue Cambridge, MA 02138 May 2004 Prepared for the Handbook of Economic Growth edited by Philippe Aghion and Steve Durlauf. We thank the editors for their patience and Leopoldo Fergusson, Pablo Querubà ­n and Barry Weingast for their helpful suggestions. TheRead MoreSurvival Strategy for Startup Business10775 Words   |  44 Pagesappreciate the comments of the journal associate editor and reviewers, as well as the financial support of the Ewing Marion Kauffman Foundation. All remaining errors are ours. Product Strategies and Firm Survival in Technologically Dynamic Industries ABSTRACT Studying the US personal computer industry from its inception in 1974 through 1994, we address the following questions. What product strategies increase the survival chances of entrants into new, technologically dynamic industries? Does the effectivenessRead MoreMonte Carlo Simulation218872 Words   |  876 Pages19 21 25 32 36 39 39 39 43 44 47 49 53 54 58 63 63 65 71 79 79 79 90 93 2 3 x Contents 3.3 3.4 3.5 3.6 3.7 3.2.1 Basic Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93 3.2.2 Path-Dependent Options . . . . . . . . . . . . . . . . . . . . . . . . . . . 96 3.2.3 Multiple Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104 Gaussian Short Rate Models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108Read MoreImpact of Globalization and Bangladesh18126 Words   |  73 PagesMONITORING AGENCY NAME(S) AND ADDRESS(ES) 10. SPONSOR/MONITOR’S ACRONYM(S) 11. SPONSOR/MONITOR’S REPORT NUMBER(S) 12. DISTRIBUTION / AVAILABILITY STATEMENT Approved for public release; distribution is unlimited. 13. SUPPLEMENTARY NOTES 14. ABSTRACT Over the past decades, globalization has now become a new world order, which virtually influences everything that comes in our mind. Developing countries like Bangladesh with vulnerable geopolitical locations and weak economies are now lookingRead More4g Communication22481 Words   |  90 Pages4G WIRELESS COMMUNICATIONS Anto vinoth.M, Punith Maharishi.Y.R antovinoth.m@gmail.com maharishipunith@yahoo.com Abstract— Mobile communication is continuously one of the hottest areas that are developing at a booming speed, with advanced techniques emerging in all the fields of mobile and wireless communications. With this rapid development it is expected that fourth generation mobile systems will be launched within decades. 4G mobile systems focus on seamlessly integrating the existingRead MoreRetailing Characteristics of Fast Food Stores and Their Impact on Customer Sales and Satisfaction29639 Words   |  119 Pages Research Framework and Methodology 3.1 Research purpose†¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦ 3.2 Hypothesis†¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦.. 3.3 Data Collection†¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦ 3.4 Methodology†¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦ 3.5 Factor Analysis†¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦ ï  ¶ Chap-4 Result and Interpretation 4.1 Interpretation of Result†¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦..†¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦.. ï  ¶ Chap-5 Suggestions and Managerial Implications ï  ¶ Chap-6 Limitations of the study References†¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦..