Multinational investment in the form of the green belt has caused a change in the rainfall pattern in Jamnagar – how has this change affected the crop yield in the village of Padana. GROUP 7

HYPOTHESIS The change in climatic conditions, due to the green belt, has led to an increase in the crop yield in the village of Padana

Introduction Nutrients in soil Crop yield Water harvesting Effect Of Change In Climatic Conditions pH of soil

PHYSICS AIM: To investigate the rainwater harvesting system used by the farmers in the village of Padana and explore the working and efficiency of this system.

What is the rainwater harvesting system? Since the green belt has come in, the average annual rainfall has increased from 300 mm per annum to more than 600 mm per annum. The farmers in the village of Padana are harvesting this rainwater and using it to irrigate the fields.

How the system works? The rainwater is collected in a large reservoir (shown alongside). Some water is collected in tanks using suction pumps. The water seeps below into the ground to reach the water table. The rain water in the water table is accessed by all farmers through wells.

Data Collection Depth of the water (h) = 300 feet Voltage supplied to the submersible pump = 230 V Current supplied to the submersible pump = 15 A Energy Input to the pump = 4 kWh Submersible Pump

Calculation Depth of the water (h) = 300 feet = m Density of water (þ) = 1000 kg m -3 (assuming that the water is pure) Acceleration due to gravity (g) = 9.8 m s -2 Pressure at the bottom of the pipe = hþg = X 1000 X 9.8 = 8.9 X 10 5 Pa = 8.9 X 10 2 kPa In 1 hour, Energy input to the pump = 4 kWh Energy output of the pump = VIt = 230 X 15 X 3600 = J = 3.45 kWh Efficiency of the pump (ŋ) = Energy output 100 Energy input = 3.45 X 100 = 86.25% 4.00

Conclusion Assuming that the water is completely pure, the submersible pump works 86.25% efficiently.

Evaluation In reality, the subversive pump does not work 86.25% efficiently because the water used is not completely free of impurities. Limitations: 1.We could not measure the density of water as water was deep inside the well and could not be removed when we were in the village. 2.We could not run the submersible pump as there was no electricity at the time of our visit. Consequently, we could not measure the water outflow.

CHEMISTRY AIM: To experimentally determine the pH, mineral content and salinity of the soil; and to investigate the difference between these values and those recorded in 1998 (before the refinery came up).

Hypothesis The rainfall should affect the pH of the soil. It is likely that an increase in the rainfall should have resulted in the pH of the soil decreasing.

METHOD Soil samples were collected from the field The soil was dissolved into water and then filtered Using logger pro and the pH probe, the pH of the filtrate was recorded The ion-specific probes were pre-soaked and prepared The probes were then calibrated for use. The recordings for ammonium, nitrate ions and chloride ions was taken The salinity sensor was also used to record the salinity of the soil

SOIL pH Rainfall/mm per annum 300 mm600 mm pH of soil Note: The data for the year 1998 was obtained from the Reliance Horticultural Department. The rainfall for this year is the rainfall as predicted by the Reliance Horticultural Department. The pH of the soil for this year was experimentally calculated in the laboratory, using the pH probe.

This shows us that the rain water has helped lower the soil pH and has thus made the soil more neutral However, there are several other factors that affect the soil pH like the crop being grown, season (time of the year) and the addition of The PH can also change by a large amount by the addition of slaked lime and other additives.

NUTRIENTS The data for the year 1998 was obtained from the Reliance Horticultural Department. The data for the year 2007 was experimentally calculated using sensors in the laboratory.

Soil Salinity Salinity (using Salinity Sensor): 120 Parts Per Million This low value for the salinity can be attributed to the fact that its a semi arid region This is a low amount of salinity that is typical of desert soils. The low pH has several negative effects and can pose several problems: Low salinity changes the electrochemical balance of soil particles. It destroys physical soil properties, reduces its draining capacity, and increases evaporation and soil erosion. Salinity disrupts the ion exchange mechanism between soil moisture and plant cells.

EVALUATION Limitations: The Calcium probe did not work The sensors were very difficult to calibrate properly Limitation of a single sample The values were taken only once and hence the yearly variations can not be accounted.

BIOLOGY AIM: To investigate how the change in rainfall, temperature and mineral content of the soil have lead to an increase in the crop yield.

Change in temperature, pH and rainfall over the years…. Year Temperature (ºC) pH> Rainfall (mm)< 300> 600

How Multinational investment affects the farmers…

FERTILIZERS As we can see in the following table there has been a change in the nutrient values over the years Nutrient Potassium / mg l -1 < 140> 250 Phosphorus / mg l -1 <30>40 Nitrogen / mg l -1 <280>350 SOURCE: RELIANCE HORTICULTURE DEPARTMENT

CONCLUSION As a result of the increase in rainfall and the decrease in temperature (due to Green Belt), the fertility of the soil and the percentage yield of the crops have increased. Due to the introduction of the refinery, employment has increased – thus the farmers are now able to spend on expensive fertilizers.

Acknowledgements We would like to thank: Kokilaben Dhirubhai Ambani Vidyamandir The Reliance Horticultural Department Our teachers: Mr. Gerard Coleman Mr. Yassir Choonawalla Mr. Abhimanyu Basu Mrs. Mou Maiti Mrs. Manjodh Mitra Mr. Paul Stone Ms. Janet Deane Mr. Ananda Athukorala Mr. Sharad Gulhane Ms. Savita Presented by: Anuraag Jain Karan Dhruve Krish Mehta Mihika Kothari Shivashree Ghogale Trishla Selarka Vatsal Neelankantan Yashna Shah