11. Animal urine forms part of the nitrogen cycle . 12. All these processes contribute to the nitrogen cycle . 13. His research contributions lead to the finding that the photorespiratory nitrogen cycle is an open process. 14. An arbuscular mycorrhizal fungus significantly modifies the soil bacterial community and nitrogen cycling during litter decomposition. 15. It has subsequently been cited in numerous other papers dealing with changes in the nitrogen cycle . 16. It is also needed in the reduction of nitrate into ammonia for plant assimilation in nitrogen cycle . 17. In the artificial environment of the aquarium, the nitrogen cycle effectively ends with the production of nitrates. 18. Therefore, as part of the nitrogen cycle , it is essential for agriculture and the manufacture of fertilizer. 19. The discovery of anammox process modified the concept of biological nitrogen cycle , as depicted in Figure 2. 20. A simple diagram of the nitrogen cycle .
