nutrient cycle

In order to fertilize the soil fertility, the model of nutrient balance demands that the surplus of N should be over 40% so as to achieve a good nutrient cycle in the oases agro-ecosystem.

为了培肥地力，模式养分平衡要求N盈余在40%以上，以实现绿洲农业生态系统养分良性循环。

A Study of the Nutrient Cycle in Aerially Seeded Pinus massoniana of Hunan Province

湖南省马尾松飞播林的养分循环研究

Effects of cultivation system on nutrient cycle of purple soil

耕作制度对紫色土养分循环的影响

Nutrient cycle in three types of standing density of aerially seeded Pinus massoniana of were also studied in this paper.

对3种不同密度类型的马尾松飞播林分的养分循环进行了研究。

Soil biological factors are important factors leading to the reduction of cotton output for the continuous cropped cotton, as well as important factor in promoting nutrient cycle and the growth of cotton.

土壤生物学因素不仅是导致棉花连作减产的重要因素，也是促进养分循环，促进棉花生长的重要因素。

According to the research and practice on nutrient cycle of black locust forest stands in the area of gulled loess plateau, some key problems in the research of nutrient biogeochemical cycle have been discussed.

根据对黄土残塬沟壑区刺槐林地养分循环的研究和实践，对有关养分生物地球化学循环研究中遇到的若干问题进行了讨论。