Coordination of the Research Unit and development of a conceptual model of paddy soil evolution

研究单位的协调和水稻土演化概念模型的开发

• 批准号: 60229052
• 负责人: Professorin Dr. Ingrid Kögel-Knabner
• 金额: --
• 依托单位: Institute of Soil Science
• 依托单位国家: 德国
• 项目类别: Research Units
• 财政年份: 2008
• 资助国家: 德国
• 起止时间: 2007-12-31 至 2017-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/60229052?language=en
• 关键词: Coordination; Research; Unit; development; conceptual

Paddy soils may originate from many different types of soil but are highly modified by human activities. They are mostly managed under submerged conditions, leading to a unique agroecosystem in terms of element cycling. However, climate change and competition from other sectors will severely affect water availability for rice cropping. Thus, a joint international workshop, organised by two DFG Research Units focussing on paddy rice production and associated paddy soil development aims at gaining more insight into processes of C and N balances due to different management systems. The DFG Research Unit 995 (Biogeochemistry of Paddy Soil Evolution) focusses on the identification of soil forming processes responsible for paddy soil evolution. To understand paddy soil evolution, we have to consider the dynamics of hydrologically and microbially mediated redox processes to the dynamics of soil minerals and soil organic matter. This is strongly related to the question of the microbial accessibility of organic carbon (OC) and nitrogen (N), but also of iron (Fe). Different initial natural conditions may require different management practices for rice cultivation, and these may determine the direction of paddy soil evolution. The direct comparison of paddy soils and non-flooded agricultural soils allows to identify and to quantify management induced differences of biogeochemical properties in different soil types. These investigations are strongly related to the DFG Research Unit 1701 (Introducing Non-Flooded Crops in Rice Dominated Landscapes: Impact on Carbon, Nitrogen and Water Cycles, ICON). This Research Unit explores and quantifies the ecological consequences of crop diversification in rice dominated landscapes. Diversion from two flooded rice crops per year to rotations with one or two non-flooded crops, such as maize or non-flooded (aerobic) rice, entails pronounced implications in terms of hydrology, element cycling and ecosystem functioning. The higher OC content in rice/rice rotations as compared to rice/maize rotations only partially compensates for higher methane (CH4) emissions. Reduced CH4 emissions in non-flooded crops are at least in part offset by increased N2O emissions (pollution swapping). Addressing these aspects trans-disciplinary will help understanding and quantifying the short and long term dynamics of carbon, nitrogen and water in up-coming rice ecosystems. Thus, integrating the results and knowledge of both Research Units as well as the exchange of experiences with international scientists with professional expertise on paddy rice production will contribute greatly to deepen our insights concerning management-depending biogeochemical processes in paddy soils.

稻田可能起源于许多不同类型的土壤，但人类活动高度改变。它们主要在淹没条件下进行管理，从而导致元素循环的独特农业生态系统。但是，来自其他部门的气候变化和竞争将严重影响水稻种植的水利用率。因此，由两个DFG研究单元组织的联合国际研讨会侧重于稻米生产和相关的稻田开发，旨在更多地了解由于不同的管理系统而引起的C和N余额的过程。 DFG研究单元995（Paddy土壤进化的生物地球化学）着重于鉴定负责稻田进化的土壤形成过程。为了了解稻田的演化，我们必须考虑水文和微生物介导的氧化还原过程的动力学，以对土壤矿物质和土壤有机物的动力学。这与有机碳（OC）和氮（N）的微生物可及性以及铁（FE）的微生物可及性问题密切相关。不同的初始自然条件可能需要不同的管理实践来进行水稻种植，这些方法可能决定了稻田进化的方向。稻田和非液化农业土壤的直接比较允许识别和量化管理诱导的不同土壤类型中生物地球化学特性的差异。这些研究与DFG研究单元1701密切相关（在水稻主导的景观中引入非液化作物：对碳，氮和水周期的影响，图标）。该研究部门探索并量化了水稻主导景观中农作物多样化的生态后果。从每年两种洪水作物转移到用一种或两种非液化作物的旋转，例如玉米或非滴虫（有氧）大米，对水文，元素循环和生态系统功能的含义具有明显的影响。与水稻/玉米旋转相比，水稻/稻旋转中的OC含量较高，仅部分补偿了较高的甲烷（CH4）排放。非液化作物中CH4排放量减少至少部分被N2O排放量增加（污染交换）。解决这些方面的跨学科将有助于理解和量化即将到来的水稻生态系统中碳，氮和水的短期和长期动态。因此，将两个研究单元的结果和知识整合在一起，以及与国际科学家的经验以及具有稻米生产专业专业知识的经验将极大地加深我们关于稻田中管理层探索生物地球化学过程的见解。