Alternative Nutrient Cycles for Terrestrial Plants, Positive Feedbacks through Detrital Processes, and Nutrient Use Efficiency

육상식물 중심의 영양소 순환 경로와 부식과정에 의한 양성 되먹임과정, 그리고 영양소 이용효율

Six nutrient cycles involving terrestrial plants are identified and characterized. Plants affect biotic and abiotic cycles through their effects on soil properties. They determine their internal nutritional status and nutrient concentrations in their environment via internal and external cycles. Contributions of organic matter to mycorrhizal, trophic, and detrital mediated external cycles and alterations of nutrient concentrations by plants can promote positive feedbacks leading to increased availability and retention of soil nutrients in open systems. Recognizing alternative cycles through plants leads to a definition of nutrient use efficiency for ecosystems: the ratio of system production to nutrient content of organic matter. A simple graph model to predict changes of nutrient use efficiency during primary succession is then presented.