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Chapter topics:
- Soil fertility
- Factors which influence soil fertility
- How soil loses fertility
- Maintenance of soil fertility
A valid license for package „Opiq Private User Package”, „Opiq Pupil Package” or „Opiq Teacher Package” is required to use the kit. Click the link with the package name to learn more about the package and order a license.
If you have a valid license, log in to view the chapter.
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