Certified Crop Adviser with Sustainability Specialty Circular Economy & Bio-based Resources: practice questions

Question 1 · medium

Why are used agricultural plastics such as silage film and mulch film hard to recycle to high value?

1. They are made of metals that must be smelted at very high temperature
2. They are legally classified as hazardous waste in every country
3. They are thin and contaminated with soil, water and organic matter
4. They are always fully biodegradable and break down before collection

Question 2 · easy

Which contaminant group is the main constraint on returning sewage sludge and compost to farmland?

1. Heavy metals, pathogens and persistent organic pollutants
2. Dissolved oxygen and carbon dioxide released during composting
3. Cellulose and lignin
4. Nitrogen and phosphorus

Question 3 · medium

Machinery rings and custom hiring centres for farm equipment are examples of which technical-cycle loop?

1. Recycling, which recovers steel from scrapped farm machinery
2. Remanufacturing, which restores used engines to as-new condition
3. Sharing, which raises the use of assets idle most of the year
4. Composting, which returns organic matter to the farm soil

Question 4 · medium

Why can removing most crop residues for bioenergy or materials conflict with circular agriculture?

1. Residues returned to soil maintain soil organic carbon and recycle nutrients
2. Residues left in fields always raise methane emissions above those of burning
3. Residues contain no nutrients, so their removal has no effect on soil fertility
4. Residues must by law be sold to power plants in every producing country

Question 5 · medium

Why is phosphorus recovery considered strategically important in circular agriculture?

1. Phosphorus is a greenhouse gas whose emissions must be captured from manure stores
2. Phosphorus can be fixed from the air by legumes, so recovery reduces their yields
3. Phosphate rock is finite, concentrated in few countries and listed by the EU as a critical raw material
4. Phosphorus fertiliser is made from natural gas, so its price follows international oil and gas markets closely

Question 6 · hard

In the 'low-opportunity-cost feed' concept, which feed best fits a circular livestock system?

1. Maize grain grown on prime arable land suitable for human food
2. Soybean meal imported from land recently converted from forest
3. Grass from land unsuitable for crops and food-processing by-products
4. Wheat grain of milling quality diverted from bread production

Question 7 · medium

A farmer returns 5 t of dry crop residue per hectare containing 45 % carbon. With a humification coefficient of 0.15, how much carbon is retained in soil organic matter?

1. 2.250 t C/ha
2. 0.750 t C/ha
3. 1.237 t C/ha
4. 0.337 t C/ha

Question 8 · medium

EN 17033 applies to which product, with what biodegradation requirement?

1. Compostable carrier bags, 60 % biodegradation in home compost within one year
2. Marine fishing nets, 90 % biodegradation in sea water within six months
3. Paper packaging, 50 % biodegradation in landfill within five years
4. Soil-biodegradable mulch films, 90 % biodegradation in soil within two years

Question 9 · medium

Leasing a tractor, with the dealer retaining ownership and responsibility for maintenance, is which PSS type?

1. Result-oriented service
2. Product-oriented service
3. Use-oriented service
4. Sharing platform for consumer goods

Question 10 · medium

Pooled returnable plastic crates for fruit and vegetables, washed and tracked by a service provider, mainly deliver which circular strategy?

1. Closing loops by recycling the crates after every single trip
2. Narrowing loops by using thinner single-use cardboard boxes
3. Regenerating soils by composting the crates at end of life
4. Slowing loops through reuse of the same packaging many times