Element cycles in forests and grasslands of the Biodiversity Exploratories: Response to management intensity and associated biodiversity

水和养分循环的调节是四类主要生态系统服务中的两类，它们受到土地管理的强烈影响，并受到生物多样性和生物群落组成的控制。土地利用和生物多样性经常相互关联，土地利用的集约化被认为是生物多样性面临的五大威胁中最重要的一个。BECycles将继续对生物多样性探索站所有VIP地块上的水、C、N、P、H+和贱金属的循环进行长期观察。元素收支将通过降雨、穿透雨、树干茎流、土壤溶液中的元素通量以及地上凋落物中的元素通量进行评估，每两周一次。除了元素平衡，我们还致力于借助先进的分析方法，提高对氮循环以及溶解和颗粒有机物（DOM，POM）的过程理解。这些包括天然丰度稳定同位素测定、溶解有机物的分子表征、叶圈微生物群落的化学和微生物表征、POM的粒度测定以及微量热法和土壤和土壤溶液的实验室矿化实验的组合。通过将这些方法与贝叶斯建模相结合，将使我们能够将生态系统服务和功能（如C和N循环以及养分利用效率）与土地利用强度和生物多样性联系起来。通过包括可用的非生物地块属性和土地利用措施的模型（结构方程，贝叶斯和pedotransfer函数），我们进一步的目标是外推元素循环和预算从VIP到EP水平。

The regulation of water and nutrient cycling are two out of four main groups of ecosystem services, which are strongly influenced by land management and additionally controlled by biodiversity and organism community composition. Land use and biodiversity are frequently related and intensification of land use is regarded as the most important of five major threats to biodiversity. BECycles will continue the long-term observation of the cycling of water, C, N, P, H+, and base metals on all VIP plots of the Biodiversity Exploratories. Element budgets will be evaluated by element fluxes in rainfall, throughfall, stemflow, soil solutions and additionally in aboveground litterfall in biweekly resolution. In addition to element balancing, we aim at improving process understanding of cycling of N as well as dissolved and particulate organic matter (DOM, POM) with the help of sophisticated analytical methods. These include natural abundance stable isotope determinations, molecular characterization of dissolved organic matter, chemical and microbial characterization of the phyllosphere microflora, particle-size determination of POM, and combinations of microcalorimetry and laboratory mineralization experiments of soil and soil solution. The combination of results gained by the application of these methods with Bayesian modelling will enable us to relate ecosystem services and functioning like C and N cycling and nutrient use efficiency to land-use intensity and biodiversity. By including available abiotic plot properties and land-use measures in models (structural equation, Bayesian, and pedotransfer functions) we further aim at extrapolating element cycling and budgets from the VIP to the EP level.