A novel approach to measure nutrient fluxes in permeable sediments

测量可渗透沉积物中养分通量的新方法

• 批准号: NE/X012654/1
• 负责人: Anna Lichtschlag
• 金额: $ 12.76万
• 依托单位: NATIONAL OCEANOGRAPHY CENTRE
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2022
• 资助国家: 英国
• 起止时间: 2022 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=NE%2FX012654%2F1
• 关键词: novel; approach; measure; nutrient; fluxes

Around the globe, the coastal ocean is of immense importance, as it provides critical functions for the environment, society and economy. Sediments play a fundamental role in the wellbeing of the coastal ecosystems as they are able to convert, store and release chemical compounds that affect and control life. For example, sediments are a major sink for oxygen, but it is also suggested that coastal sediments are very important in the recycling of nutrients, a process that controls primary production, but also plays a role in the production of algal blooms or low oxygen conditions in coastal waters. However, due to the specific geophysical characteristics of many coastal sediments (i.e. they often are composed of loose sand grains), measurements that quantify the nutrient exchange between the sediments and water column are very difficult and hence the recycling capacity of nutrients in these sandy sediments is not well quantified, even though it is likely to be highly important.Here we propose a proof-of-concept study to develop a new capability to quantify the exchanges of nutrients between different types of sandy sediments and the water column. To achieve this, we will adapt a well-known technique to measure oxygen exchange between sediments and the water column (i.e. so called benthic chambers). We will equip these flux exchange recorders with novel miniaturized sensors that autonomously can measure nutrient concentrations in an enclosed volume of water. We will also integrate them with sensors measuring water flow and sediment bed properties. We first will verify the functioning of the new approach in the laboratory and then demonstrate it in a real-world scenario. For this we have chosen an area along the UK South Coast, that is known for high nutrient levels, caused by agricultural discharges, wastewater, urban runoff and sewer overflows, and where high nutrient inputs historically already led to algal blooms and low oxygen concentrations in the water column. This novel capacity can produce knowledge that is urgently needed to sustain a healthy environment and manage our natural resources and on the longer-term can be adapted to measure other geochemical species, e.g. other pollutants and in different environments.

在全球范围内，沿海海洋非常重要，因为它为环境，社会和经济提供了关键的功能。沉积物在沿海生态系统的福祉中起着基本作用，因为它们能够转换，存储和释放影响和控制寿命的化学化合物。例如，沉积物是氧气的主要水槽，但还建议沿海沉积物在养分的回收中非常重要，这一过程可以控制原发性生产，但在沿海水域的藻类开花或低氧条件下也起作用。但是，由于许多沿海沉积物的特定地球物理特征（即它们通常是由松散的沙粒组成），因此量化沉积物和水柱之间养分交换之间的养分交换非常困难，因此在这些沙质沉积物中不太量化的量化能力是非常重要的。不同类型的沙质沉积物和水柱之间的养分。为了实现这一目标，我们将适应一种众所周知的技术来测量沉积物和水柱之间的氧气交换（即所谓的底栖腔室）。我们将为这些通量交换记录器配备新型的微型传感器，这些传感器可以自主地测量封闭水量的水中的营养浓度。我们还将它们与测量水流和沉积床特性的传感器集成在一起。我们首先将验证实验室中新方法的功能，然后在现实世界中证明它。为此，我们选择了沿英国南海岸的一个地区，该区域是由农业排放，废水，城市径流和下水道溢出引起的高营养水平而闻名的，并且历史上已经导致了高养分输入的水位，并且水柱中的高氧气浓度很高。这种新颖的能力可以产生迫切需要维持健康环境并管理我们的自然资源的知识，并且可以改编自其他地球化学物种，例如其他污染物和不同环境。