ES 100 HW3, Part II: Population & Community Ecology Due: Wednesday, August 29st (50points; 7 points each)1. Consider the simplified kelp food web shown below [cbc.amnh.org/crisis/images/otter1.gif]a. How can top predators (like the sea otter) promote biodiversity in the web (describe two fundamental ways)? Make reference to the diagrams, above, in your answer.b. According to the diagram, what do large crabs eat? Which organisms eat them? What organisms do they compete with? (5 points)c. Assume that larger crab populations follow a logistic growth curve, and write an equation that would model the large crabs’ position in the food web (be sure your equation accounts for species interactions). Define all terms in your equation (with units) clearly. [HINT: look at the equation for the Fox on slide 33-34 of theWeek 3, Wednesday lecture. Notice that “plants” are NOT included in the equation, because they would already be accounted for in the modeled population of mice]d. Which would be a larger “interaction coefficient,” the effect of a sea otter on an urchin, or the effect of an urchin on a sea otter? In other words, which is higher, aUO or aOU, (where U= urchin and O= otter)? Why? (5 points)OVER, PLEASE2. Read the article “Ecologically Sustainable Yield” by Zabel, et al. (2003). The article is available on the ES 100 course website.a. How has technology contributed to the collapse of marine fisheries (provide a few specific examples)?b. Why do the authors feel that the “fundamental goals of modern fisheries management may be incompatible with sustaining ecosystems?” How do you think that this apparent conflict cab be resolved? (8 points)c. Do you think that “fishing down the foodweb” is an example of human’s acting asoptimal foragers?