Soil Fertility - Sustainable Soil Management - Past Exam, Exams of Biology

Download Soil Fertility - Sustainable Soil Management - Past Exam and more Exams Biology in PDF only on Docsity! ARHOLIADAU EXAMINATIONS SEMESTER 1 EXAMINATIONS 2010 IBERS (BIOLOGICAL SCIENCES) BS13710 SUSTAINABLE SOIL MANAGEMENT TIME ALLOWED: TWO HOURS ANSWER THREE QUESTIONS 1. Explain how aggregation processes and the importance of aggregation for soil fertility varies with soil texture. 2. Why do soils in Wales tend to acidify and what are the processes leading to this acidification? How do different soil types vary in their capacity to buffer against acidification and in their lime requirements to restore target pH? 3. Describe how some land management practices affect the size and composition of populations of soil organisms. Give two examples of how these effects can have practical implications 4. How have changes in UK farming over the last 50 years increased levels of soil compaction and erosion. 5. Describe the beneficial effects of organic matter in soils. 6. Describe the major mechanisms of N loss from soils and explain why this is environmentally harmful. END