A global estimate of terrestrial net secondary production of primary consumers

Aim: Net Secondary production (NSP) emerges from the consumption of Net Primary Production (NPP) by any heterotrophic organism. There has been sporadic interest in the importance of NSP, but no global estimates have been produced. We revisit NSP and attempt a global estimate using contemporary NPP data combined with modern metabolic scaling theory for consumption rates. We distinguish between potential NSP as the amount of secondary production that could be supported by NPP, and realized NSP as the amount remaining after anthropogenic habitat disruption. Location: Global Time period: 2000-2014 Methods: We present a model of NSP implementing a Type II functional response for consumption rates wherein search efficiency and handling time are calculated based on consumer mass and ambient temperature. We solve this model for each 0.05-decimal-degree pixel in the global terrestrial biosphere using as data inputs NPP (MOD17A3) and land-surface temperature (MOD11C3). We aggregate estimates wit...

研究目标：净次级生产（Net Secondary Production, NSP）源自各类异养生物（heterotrophic organism）对净初级生产（Net Primary Production, NPP）的消耗。学界对净次级生产重要性的关注向来零散，迄今尚未产生全球尺度的估算成果。本研究重新审视净次级生产问题，结合当代净初级生产数据与现代消费速率代谢缩放理论，尝试开展全球尺度估算。我们区分了两类净次级生产：潜在净次级生产指净初级生产所能支撑的次级生产总量，实际净次级生产则指经人为生境破坏后剩余的次级生产总量。
研究区域：全球范围
时间跨度：2000年—2014年
研究方法：本研究构建了净次级生产模型，采用II型功能响应（Type II functional response）描述消费速率，其中搜索效率与处理时间基于消费者体重与环境温度计算得出。我们以净初级生产数据（MOD17A3）与地表温度数据（MOD11C3）作为输入数据，针对全球陆地生物圈每0.05十进制度像素求解该模型。随后对估算结果进行聚合……