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2089年优先计划“根际时空组织-根际功能的关键”的已批准协调提案的补充。本补充资料是在Bad Lauchstädt野外站建立中央土壤试验的估计成本，PP 2089的大多数研究小组都要求进行该试验， 增长了58%。资金缺口的原因是： 2017年至2018年建筑成本普遍上涨约6%· 投标期短，建筑业产能利用率高 （项目批准10/07/2018;工作必须在冬季之前进行）· 开挖工程的更详细规范（附录I，3.1，3.2） （垂直侧壁-公差± 5 cm;使用轻型振动器压实土层）· 为减少压力荷载，模板要求更高（附录I，5.1）· 石英砂的供应商必须更换，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I，7.2）。资金缺口太大，无法通过削减协调项目的其他职位来弥补。因此，如果没有补充剂，中心区实验就处于危险之中。或者，协调项目无法完成其最初的任务（在整个三年期间的田间小区试验中对芽、根和土壤样品进行取样和分析，组织年度会议，综合，科学委员会，包括差旅费，国际会议，研讨会/辅导，以及青年研究者会议）。

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).