Supplement for compensation of additional construction costs for the central plot experiment of PP 2089 at the field station Bad Lauchstädt

目前的提案是对优先方案2089“根际时空组织--根际功能的关键”的已获批准的协调提案的补充。由于PP 2089的大多数研究小组所需的在巴德·劳赫斯特(Bad Lauchstädt)野外站点建立中央土壤小区实验的估计费用增加了58%，因此需要补充这一补充资料。资金缺口的原因是：·2017-2018年建设成本普遍增加约6%·投标周期短，加上建筑业产能利用率高(项目审批10/07/2018；冬季前必须进行工作)·更详细的开挖工程规范(附件I，3.1，3.2)(垂直边墙-公差±5厘米；用轻质振动器压实土层)·减少压力负荷对模板模板的更大需求(附件一，5.1)·石英砂供应商不得不改变，因为预计的供应商无法提供所需质量的必要数量(不含碳酸盐)(附件一，7.2)。资金缺口太大，协调项目其他职位的削减无法弥补。因此，如果没有补充，中心小区实验将面临风险。或者，协调项目无法完成其最初的任务(在整个三年的田间小区实验中对地上部、根部和土壤样本进行采样和分析，组织年度会议，综合，科学委员会，包括旅费，国际会议，研讨会/教程，以及青年研究人员会议)。

The current proposal is an addition to the approved coordination proposal of the priority program 2089 ‘Rhizosphere spatiotemporal organisation – a key to rhizosphere functions’. This supplement is required as the estimated costs for the establishment of the central soil plot experiment at the field station Bad Lauchstädt, required by most research groups of PP 2089, increased by 58% . The reasons for the financial gap are:• the general increase in construction costs from 2017 to 2018 by about 6%• the short bid period combined with high capacity utilization of building industry (project approval 10/07/2018; work has to be conducted before winter)• more detailed specification of excavation work (Annex I, 3.1, 3.2) (vertical side walls – tolerance ± 5 cm; compaction of soil layers with a light weight vibrator) • larger requirement of form-work panels to reduce pressure load (Annex I, 5.1)• supplier of quartz sand had to be changed as the foreseen supplier is not able to provide the necessary amount in the required quality (free of carbonate) (Annex I, 7.2).The financial gap is too large to be covered by cutbacks in other positions of the coordination project. Hence without the supplement the central plot experiment is at risk. Alternatively the coordination project cannot fulfill its original tasks (sampling and analysis of shoot, root and soil samples in the field plot experiment throughout the three year period, organisation of annual meetings, synthesis, scientific board including travel expenses, international conference, workshop/tutorials, and young investigator meetings).