Unit 1: Fundamentals of Organic Manures and Fertilizers - Practice Quiz

1 What is organic manure?

2 What is the main purpose of applying fertilizer to crops?

3 Which material is commonly used to prepare farmyard manure?

4 Which of the following is an organic manure?

5 Which fertilizer is a common source of nitrogen?

6 Which three nutrients are represented by the letters NPK?

7 What does composting primarily involve?

8 Which organisms play a major role in decomposing materials during composting?

9 What is a major benefit of adding organic manure to soil?

10 How do organic manures generally release nutrients?

11 What is green manure?

12 Which type of plant is commonly used as green manure?

13 What is vermicompost produced with the help of?

14 Which material is suitable for compost preparation?

15 What is meant by a chemical fertilizer?

16 Which nutrient mainly supports leafy vegetative growth?

17 Which nutrient is especially important for root development?

18 Which nutrient commonly helps plants improve stress tolerance and overall vigor?

19 What is a bulky organic manure?

20 Why should fertilizers be applied at recommended rates?

21 A farmer wants to improve soil aggregation, water-holding capacity, and nutrient supply over several seasons. Which input is most suitable?

22 A standing crop shows severe nitrogen deficiency and requires a rapid correction. Which input would generally produce the quickest response?

23 Which material is best classified as a concentrated organic manure rather than a bulky organic manure?

24 A leguminous crop is grown specifically to be incorporated into the soil before the main crop. What is the primary purpose of this practice?

25 A farmer applies 2 tonnes of dry compost containing 1.5% total nitrogen. How much total nitrogen is added?

26 Two organic materials contain similar total nitrogen, but Material X has a much lower carbon-to-nitrogen ratio than Material Y. What is most likely after incorporation?

27 Fresh cereal straw with a high carbon-to-nitrogen ratio is incorporated immediately before sowing. What short-term effect is most likely?

28 Which observation provides the strongest practical evidence that a compost pile has reached maturity?

29 Seedlings are damaged after a large quantity of soluble fertilizer is placed directly beside the seed. What is the most likely cause?

30 A farmer applies compost to improve soil organic matter and uses a soil-test-based fertilizer dose to meet immediate crop demand. This approach is best described as:

31 A fertilizer is labeled 10-5-5, representing percentages of N, , and . How much nitrogen is present in a 50 kg bag?

32 Two manure samples have different moisture contents. Which basis should be used to compare their nutrient concentrations fairly?

33 In a soil where applied phosphorus is readily fixed, which practice can improve the efficiency of a phosphorus fertilizer?

34 Which manure-management practice creates the greatest immediate risk of nutrient loss to surface water?

35 Compared with a single-nutrient mineral fertilizer, well-decomposed organic manure generally provides:

36 Repeated use of an ammonium-based nitrogen fertilizer without liming may gradually produce which soil change?

37 A manure heap varies in composition from its outer layer to its center. Which sampling method will best represent the entire heap?

38 Which statement most accurately distinguishes organic manure from a typical mineral fertilizer?

39 A crop requires 60 kg of nitrogen per hectare. If a fertilizer contains 20% nitrogen, how much fertilizer is required per hectare, assuming the full labeled amount is used in the calculation?

40 A laboratory report shows that compost contains substantial total nitrogen, but the crop still develops nitrogen deficiency soon after application. What is the best explanation?

41 A compost sample contains 1.2% total N on a dry-matter basis, has 40% moisture, and weighs 5 tonnes as received. What mass of total N does the load contain?

42 Two manures have equal total N concentrations, but manure X has a C:N ratio of 12:1 and manure Y has a C:N ratio of 35:1. Immediately after incorporation into a low-N soil, which outcome is most likely?

43 A farmer replaces a fertilizer supplying 80 kg plant-available N with manure containing 2.0% total N on a dry basis. The manure is 25% dry matter, and 40% of its total N is expected to become available during the first season. How much fresh manure is required?

44 Which comparison best distinguishes a fertilizer grade of 10-5-8 from elemental nutrient percentages?

45 A laboratory reports 4.58% in a fertilizer. Using , what is the approximate elemental P concentration?

46 A manure loses water during uncovered storage but loses no nutrients. Which analytical result is expected when the stored sample is compared with the original sample?

47 Which observation provides the strongest evidence that a product should be evaluated as an organic manure rather than solely as a concentrated mineral fertilizer?

48 A fresh poultry manure sample contains 3.0% N, while a composted sample contains 2.4% N. Which conclusion is scientifically justified from these percentages alone?

49 A manure contains appreciable total N but very little ammonium-N or nitrate-N. What most directly determines how much of its remaining N becomes crop-available?

50 A field needs 60 kg N and 20 kg per hectare. Manure applied to satisfy the full N requirement supplies 55 kg per hectare. What is the most defensible nutrient-management interpretation?

51 Four subsamples are collected from a manure pile with visibly wet outer zones and dry inner zones. Which procedure best minimizes sampling bias before analysis?

52 A liquid manure tank stratifies during storage. A sample taken from the clear upper layer is most likely to produce which bias relative to a well-agitated representative sample?

53 Why can oven-drying a manure sample at an excessively high temperature compromise an estimate of total manure nitrogen?

54 A fertilizer labeled 18-46-0 is applied at 100 kg per hectare. Approximately how much elemental P is applied, using ?

55 A manure application supplies 120 kg total N per hectare. Of this, 25% is ammonium-N and 75% is organic N. If 20% of organic N mineralizes in year one and 30% of ammonium-N is lost before crop uptake, how much N remains potentially available in year one?

56 Which scenario most clearly illustrates why equal nutrient application rates do not guarantee equal crop response?

57 A compost has a neutral pH and a low electrical conductivity, yet a seed germination test shows strong inhibition. Which inference is most appropriate?

58 Which statement best explains why total nutrient analysis alone is insufficient for comparing an organic manure with a soluble fertilizer?

59 A 1-tonne fresh manure batch contains 70% moisture and 2% N on a dry basis. After storage, 20% of its dry matter and 25% of its original N mass have been lost. What is the N concentration of the remaining dry matter?

60 A farmer wants both rapid correction of severe N deficiency and a long-term increase in soil organic matter. Which strategy best addresses both objectives?