From: How does tillage intensity affect soil organic carbon? A systematic review
| Continent | Study country | Number of studies |
|---|---|---|
| Africa | Morocco | 2 |
| Africa | South Africa | 1 |
| Asia | China | 1 |
| Asia | Syria | 1 |
| Australasia | Australia | 21 |
| Australasia | New Zealand | 1 |
| Europe | Spain | 42 |
| Europe | Germany | 17 |
| Europe | Denmark | 7 |
| Europe | Italy | 6 |
| Europe | Finland | 4 |
| Europe | UK | 4 |
| Europe | France | 3 |
| Europe | Sweden | 3 |
| Europe | Switzerland | 3 |
| Europe | Czech Republic | 2 |
| Europe | Lithuania | 2 |
| Europe | Austria | 1 |
| Europe | Belgium | 1 |
| Europe | Ireland | 1 |
| Europe | Norway | 1 |
| Europe | Poland | 1 |
| Europe | Serbia | 1 |
| Europe | Slovakia | 1 |
| Europe | Ukraine | 1 |
| North America | USA | 142 |
| North America | Canada | 46 |
| South America | Brazil | 25 |
| South America | Argentina | 6 |
| South America | Uruguay | 3 |
| South America | Chile | 1 |