Friday 11-11:50EEMB/ES 171Problem Set #1Due: October 26, 2015 1. You are studying the effects of climate change on community ecology of ecosystems in central California. You collect the data in Table 1 for a site in the Sierra Foothills. The vegetation is dominated by chaparral and coastal sage. The rains start in the late fall and normally end by the end of April.Table 1. Climate data.SeasonAverageTemp. (° C)Rainfall(mm/season)K forcalculating PETFall 25 125 1.3Winter 5 425 1.0Spring 20 260 1.25Summer 35 60 1.4Use the following equation to calculate PET: PET (mm/season) = 3* (15 + (TEMP)K)K is a constant that depends on the season and is in the table above. Note: this is not the real formula. I came up with it as asimple equation that predicts plausible numbers. The realequations are complex and depend on latitude. Assume that the ecosystem can store a total of 100 mm of water in the soil. That means that the first rain that falls will go to satisfying PET. The next 100 mm will be stored in the soil and will be available for plant use in the following season and will be included in AET for that season. Any rainfall beyond that in a season will run off in stream flow. A. Calculate the water balance for each season. Start with a “water year” that begins with the fall. Assume no water is stored in the soil at the end of the summer. Provide estimates of PET, AET, and stream flow. Also calculate the total annual budget by summing up your seasonal estimates.Fall: AET=125mm/season, Soil=0mm/season, Stream Flow= 0mm/seasonWinter: AET=PET=60mm/season, Soil=100mm/season, Stream Flow=265mm/seasonSpring: AET=PET=172mm/season, Soil=100mm/season, Stream Flow=88mm/seasonSummer: AET=160mm/season, Soil=0mm/season, Stream Flow=0mm/seasonAnnual PET: 242mm+60mm+172mm+480mm= 954mmAnnual AET: 125mm+60mm+172mm+160mm= 517mmAnnual Stream Flow: 0mm+265mm+88mm+0mm= 353mmAnnual Soil Storage: 0mm+100mm+100mm+0mm= 200mmB. Describe the moisture conditions for plant growth in each season: Do you expect plants to be actively growing? Merely surviving? Why? In the Fall, I expect plants to be merely surviving because the PET is barely met, meaning that there is not enough water in the system. If the plants are water deficient then this water stress, which doesn’t allow plants to grow actively. In the Winter, I expect the plants to be growing at a solid rate because AET meets PET. There is also enough water supply to fulfill soil storage meaning water is abundant. Thus, I expect moderate growth in the winter however, the heavy stream flow may cause soil to erode and the sudden temperature drop may inhibit maximum growth rate. In the Spring, AETFriday 11-11:50meets PET, soil storage is fully met and there is lighter stream flow, that will not cause major erosion. Taking this into account, I believe that plant growth should be actively growing. In the Summer time, I expect the plants to be merely surviving because AET only meets about 1/3 on the PET meaning there is a high level of water stress in the environment. Without enough water, the plants in the summer season would be merely surviving.C. Using the biome figure above, what type of biome do you think this would be described as? How sensitive do you think it would be to climate change?Using the biome figure above, I think this biome would be described as a desert. I believe that this biome would be a desert due to the table and the calculations provided below. These calculations position the biome in the desert region, which is very tall and narrow. The height of the region shown in the graph shows that this biome would not be significantly affected by temperature change. On the other hand, the narrowness of the biome region correlates with the biomes high sensitivity to rainfall. Thus, this biome would be identified as a desert with low sensitivity to temperature change and high sensitivity to precipitation changes.Avg. Rainfall: 125 + 425 + 260 + 60= 217.5mm/yr = 21.75cm/yrAvg. Temp: (25° C + 5° C + 20° C + 35° C)/4= 21.25° C D. You are also studying productivity. So, you model annual net primary productivity (NPP) in this ecosystem. The equation for the global relationship between NPP and AET for each season is:NPP (g•m-2y-1 aboveground) = 1765 * Log (AET+25) – 3400Fall NPP= 1765 * Log (125+25) – 3400= 440.8g•m-2y-1Winter NPP= 1765 * Log (60+25) – 3400= 5.42g•m-2y-1Spring NPP= 1765 * Log (172+25) – 3400= 649.73g•m-2y-1Summer NPP= 1765* Log (160+25) – 3400= 601.56g•m-2y-1What would you predict annual NPP to be? 1697.51g•m-2y-1Work: 440.8g•m-2y-1 + 5.42g•m-2y-1 + 649.73g•m-2y-1 + 601.56g•m-2y-1= 1697.51g•m-2y-1E. Now assume that you actually go out and measure NPP. You get a value of 1200 g•m-2y-1 aboveground. In case you didn’t get the correct answer from part D, this is below the estimated value. Give three reasons why the actual could be lower than the predicted. Your reasons should be based in the biological/ecological controls on productivity, not in something like “the model is wrong”. Then describe, briefly, how you might determine which explanation(s) is correct? 1) One possible reason that could explain the lower value for annual NPP could be a drastic change inclimate. This change in climate could be responsible for temperature and precipitation changes which would then alter PET, AET, and ultimately changing NPP values. The change in precipitation, for example, less precipitation would be responsible for a lower AET meaning NPP also becomes a smaller value. A rise in temperature would also lower the NPP value because there could be a higher potenetial evapotranspiration value that would result in a lower AET value as well. These changes in temperature and precipitation would then be taken into account and used to determine whether or not these changes in temperature and precipitation are directly correlated withthe changes in NPP, which could then allow us to determine if the changes are responsible for the lower NPP value. These measures would then also be compared to prior climate changes to see if similar lower NPP value patterns can be associated with climate changes2) Another feasible reason that could be responsible for the lower NPP value could be that another component in the ecosystem is the limiting resource rather than water. One way to determine this would be to add a large sum of a growth component and monitor the plants response after the addition. First we would measure the