support or refute the following statements based on what you learned about energy flow, biogeochemical cycling, decomposition, trophic levels, and keystone species. You may add a diagram or illustration to support your answer. Planting mangroves is better than putting dolomite sand on the coast of the polluted Manila Bay.

according to the chart pie 1)what percentage of energy is produced by fossil fuel? 2)what percentage of energy is produced by energy technologies? 3) how much energy is produced by all alternative energy combined? U.S. energy consumption by energy source, 2017 Total 97.7 quadrillion British thermal units (Btu) Total = 11.0 quadrillion Btu geothermal 2 % solar 6% petroleum 37% - wind 21% biomass waste 4% biofuels 21% renewable energy 11% nuclear electric power 9% biomass 45% natural gas 29% wood 19% coal 14% hydroelectric 25%

This conceptual model to the right shows the flow of energy through a spring ecosystem in Silver Springs, Florida from Figure 46.8 in your textbook. 7a. Which value/number on this diagram represents gross primary productivity (GPP)? Express using the units kcal/m?/yr. Sunlight 1,700,000 kcal/m?lyr Primary producers 13,187 20,810 7,618 4,250 Primary consumers 7b. Which value/number represents net primary productivity (NPP)? Express using the units kcal/m²/yr. 2,265 3,368 1,103 720 Secondary consumers 272 383 111 90 7c. What accounts for the difference in GPP and NPP? Tertiary consumers 16 21 Decomposers 7d. What is the efficiency of energy transfer between the primary producers and the primary consumers? Is this more or less efficient than the transfer between a secondary consumer and tertiary consumer? Explain. 5,060 5,060 Total heat and respiration 20,810 respiration + heat to decomposers

Approximately how many kilograms (kg) of carnivore (secondary consumer) biomass can be supported by an area of a field containing 100 kg of plant material (assuming 10% efficiency in energy transfer)? O 10 O 100 O 1 O 1,000

“Energy flow in an ecosystem is always unidirectional". justify the statement.

Since the US has blended more and more ethanol into its gasoline, US production of ethanol has increased through your lifetime, and the data in the chart below basically show this. But production of ethanol in the US dropped slightly in the year Annual World Fuel Ethanol Production (Mil. Gal.) % of World Production Region 2014 2015 2016 2017 2018 2019 54% 30% 5% 3% 16,061 15,800 14,807 7,200 15.936 6,860 1,400 United States 14313 15,413 Brazil 6,760 7,920 8,620 6,760 1377 European Union China 1445 1387 1,430 1,440 84S 900 500 635 813 860 1,050 Canada 510 436 436 470 480 India 85 195 275 210 400 530 2% Thailand 310 334 322 370 390 420 196 Argentina Rest of World 160 211 264 290 290 290 1% 865 391 490 414 549 600 2% Total 25.083 25,774 26,182 26,810 28,570 29,100

This figure has three graphs that have important implications for understanding how carbon flow and elements cycle through ecosystems through decomposition. The figures show data on the decomposition rates in a tropical forest. Please select all of the statements that are reasonable of at least one of the figures. interpretations Daily rate of mass loss (k) from 0 to 50 days (b) 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0.0 0 Leaf mass remaining (percent) (a) 100% 80 4 60 40 20 0 0 50 100 150 Days of decomposition 12 16 8 Leaf solubility (mg C/g dry leaf) (c) Daily rate of mass loss (k) from 51 to 230 days 0.009 0.006 0.003 0.000 200 Trumpet tree Inga tree Kapok tree Brazilian firetree 250 2 3 Ratio of leaf lignin:leaf nitrogen 4 Relyea, Ecology, 9e, Ⓒ2021 W. H. Freeman and Company O Leaves that release more soluble carbon pounds decompose much faster than those that release less Leaves that are rich in nitrogen relative to lignin decompose much faster increasing the rate of the nitrogen…

Energy transferred from one trophic level to the next in an ecosystem is measured in calories, numbers, and in biomass. If a rangeland has a biomass of 100, 000g/m2 from the grass, how much biomass will be available in human beings who eat the cow that eat that grass?

A group of researchers are assessing energy availability in a terrestrial ecosystem. The image shows the food web for this ecosystem. They set up three plots and assess the biomass of producers, primary consumers, and secondary consumers. Rabbits and grasshoppers feed on ground cover plants that grow on the forest floor. Plot 1 is composed of mature hardwood trees, and only 25% of the sunlight reaches the shrubs and grasses compared to plots 2 and 3, which have fewer trees and allow more sunlight to reach the forest floor. Based on the food web shown here, which of the following best describes how the reduction in sunlight to the forest floor would impact the number of primary consumers (squirrel, grasshopper, rabbit, and deer) in plot 1 compared to the other plots? A - Plot 1 will show an increase in deer only because they feed on trees. B - Plot 1 will show a decrease in squirrels and rabbits, while deer and grasshoppers will increase. C - Plot 1 will show a decrease in rabbits and…