Answer: noun
Explanation:the study of the physical features of the surface of the earth and their relation to its geological structures
D. Appalachia would be the poorest
The use of mechanized farming techniques is well suited to geographic areas that c. have large expanses of flat land. Regions such as the Canadian Prairies is a large expanse of flat land and as such easily supports mechanization in planting crops such as wheat. Mechanization in agriculture would be hampered in areas that experience frequent flooding as equipment could get stuck in mud or suffer other water damage.
Recommended rates of potash for grazed grass are 60kg/ha and 30kg/ha of K2O for soil index 0 and 1 respectively. For soils with higher soil fertility levels no potash required.
Very large quantities of potash are removed in grass silage which must be replaced to maintain soil fertility and yield potential. The following is guide to typical potash offtakes from multi-cut silage systems.Low soil magnesium levels will affect grass yield as well as mineral balance in the animal. Apply 50-100 kg/ha MgO every three to four years at Mg index 0. Yield response is less certain at index 1 but magnesium application is justified in terms of insurance for grass yield and mineral balance for the animal, to maintain a soil magnesium index of 2.
Where lime is required and Mg levels are 0 and 1, use magnesian limestone as the most cost effective magnesium source. Where pH is satisfactory, specific magnesium fertilisers (see table below) should be used for soil improvement. Use water soluble forms of magnesium where rapid plant uptake is required.
Currents involve movement of ocean water masses, driven either by wind or by differences in temperature, salinity and density. The most important from a human perspective are the wind-driven surface currents that move water in the uppermost layer of the ocean.
Currents affect humans in several primary ways. Currents help shape the climate in the areas where we live, create the right conditions to support abundant ocean life in the areas where we fish, and change weather patterns through periodic events like El Nino/La Nina.
Ocean currents also cause upwelling in many areas like off in the inland parts of North America, where surface currents taking water away from the shore cause nutrient-rich water to well up from the ocean deeps. The abundance of nutrients in these areas forms fertile ground for kelp beds and marine fisheries, which in turn furnish food for humans. Alterations in current patterns like the El Nino/La Nina cycle affect humans as well by causing changes in local weather patterns in the years when they occur.