Analysis of soil eDNA functional genes%3A potential to increase profitability and sustainability of pastoral agriculture

Management of soil biological resources to optimise plant production, efficiency of nutrient inputs, and system sustainability is an emerging opportunity for pastoral agriculture. To achieve these goals, suitable tools that can assess the functional state of the soil ecosystem must be developed and standardised approaches to their application adopted. Towards this end, we have undertaken comprehensive, high-density functional-gene microarray analysis (GeoChip5) of environmental DNA (eDNA) extracted from 50 pastoral soils. When combined with soil, environmental and management metadata, the information can be used to provide insights into soil biological processes spanning greenhouse gas emissions, through to natural suppression of plant root diseases. To provide an example of a structured workflow of analysis in a pastoral system context, we analysed the GeoChip data using a combination of approaches spanning routine univariate methods through to more complex multivariate and network-based analysis. Analyses were restricted to comparing effects of land-use (dairy or ‘other’ farming systems), and exploring relationships of the GeoChip data with the soil properties from each sample. These exemplar analyses present a pathway for the application of eDNA approaches (GeoChip or others) to deliver outcomes for pastoral agricultural in New Zealand.

针对畜牧农业领域而言，通过管理土壤生物资源以优化植物生产、提升养分利用效率并维持系统可持续性，是一项新兴的发展契机。为达成上述目标，亟需研发可评估土壤生态系统功能状态的适配工具，并建立其应用的标准化规范。为此，我们对从50份畜牧农业土壤中提取的环境DNA（environmental DNA, eDNA）开展了全面的高密度功能基因微阵列分析（GeoChip5）。将该分析结果与土壤、环境及管理元数据相结合后，可用于解析从温室气体排放到植物根部病害自然抑制等多个维度的土壤生物过程。为展示畜牧系统场景下标准化分析流程的实例，我们结合多种分析手段对GeoChip数据进行处理，分析方法覆盖常规单变量方法，以及更为复杂的多变量分析与基于网络的分析技术。本次分析仅聚焦于比较不同土地利用类型（奶牛养殖牧场或其他农业生产系统）的土壤影响效应，并探究GeoChip数据与各样本土壤属性之间的关联关系。本次示范分析为环境DNA技术（GeoChip或其他同类技术）在新西兰畜牧农业中的应用提供了可行路径，助力其实现预期应用成效。