EEMB/ES 171Problem Set #1Due: November 3, 2014 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 forcalculatingPETFall 22 175 1.15Winter 8 400 1.0Spring 20 250 1.1Summer 30 50 1.25Use 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 tableabove. 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: PET = 3(15+221.15)= 149.93 mm 175-149.93= 25.07 mm AET=PET=149.93 mm 25.07 mm stored in soil, Stream Flow= 0Winter: PET= 3(15+81)= 69.0 mm 400+25.07-69= 356.07 mm PET=AET= 69.0100 mm stored in soil, Stream Flow= 256.07 mmSpring: PET= 3(15+201.1)= 125.96 mm250+100-125.96=224.04 mmPET=AET= 125.96 mm100 mm stored in soil, Stream Flow= 124.04 mmSummer: PET=3(15+301.25)= 255.63 50+100-255.63= -105.63AET=150 mm 0 mm stored in soil, Stream Flow= 0, 105.63 mm DeficitAnnual PET=600.52 mmAnnual AET=494.89 mmAnnual Stream Flow=380.11 mmAnnual Water Deficit= 105.63B. Describe the moisture conditions for plant growth in each season: Do you expect plants to be actively growing? Merely surviving? Why? In the fall, the plants will probably be experiencing moderate growth, since AET satisfies PET, and therefore, the environment is not under water stress, and there is some water stored in the soil. In the Winter, there should be a moderate amount of growth as well, since the AET satisfies the PET again, leaving a large amount of stream flow. There are other aspects to account for like the sudden drop in temperature, or the possible soil erosion from heavy stream flow that can inhibit the vegetation from growing at their prime. In the spring, the plant growth should be actively growing since the AET satisfies the PET, there is maximum water storage in the soil, and some stream flow, meaning no water stress and anabundant supply of water stored away. In the summer, the AET does not satisfy the PET, and as a result, there is a water deficit, meaning there is water stress in the environment, meaning the plants are merely surviving based on the water availability. 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?Average Annual Temp= (22+8+20+30)/4= 20 CAverage Annual Precipitation= (175+400+250+50)/4= 218.75 mm= 21.88 cmAccording to the figure above, the biome is most likely a desert. Because the average temperature and precipitation fall near the center as opposed to the edge of the desert section, the ecosystem may not be as vulnerable to temperature change as other biomes, but since the desert section strip is so narrow, the ecosystem may be more sensitive to precipitation.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(149.93+25))-3400= 558.66 g•m-2y-1Winter: NPP= 1765(Log(69.0+25))-3400= 82.57 g•m-2y-1Spring: NPP=1765(Log(125.96+25))-3400= 445.69 g•m-2y-1Summer: NPP= 1765(Log(150+25))-3400= 558.96 g•m-2y-1What would you predict annual NPP to be? Annual NPP= 558.66+82.57+445.69+558.96= 1645.88 g•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? Reason 1: The limiting resource is another mineral or growth component used by the plants, not water. For an example, if the plants are maybe getting nitrogen than normal, we could possibly go measure the nitrogen levels over a span of time, then add a large nitrogen supply to the environment and monitor the growth after the addition and compare it to the growth data before the addition. If there is significant response to the addition, this could tell you whether or not there was a different limiting mineral or resource.Reason 2: There could be an invasive species or disruption in the system. The invasive species could either be eliminating native species or outcompeting the native species for resources and/or sunlight. The invasive species could also be producing less energy compared to the native species. If a certain observed specieswere removed from certain areas compared to control areas in the same ecosystem, the observed difference in NPP could suggest that the invasive species had something to do with the shift in NPP.Reason 3: There could be a change in the local climate, leading to more or less precipitation or a shift in temperature. If the temperature is higher, there could be more evapotranspiration than there usually is, leading to a higher PET, with a lower AET. If there is less rain, then the PET cannot be satisfied and in turnwill lead to a lower NPP as well. We can measure the temperature or precipitation over time and compare itto past temperature and precipitation measures to see if there is correlation between the NPP and the changes in climate norms.G. Now calculate soil respiration for each season and for the