Izcedne talne vode kot neizkoriščen vir informacij o biotski raznovrstnosti tal

Soil biodiversity is the variation in soil life, from genes to communities, and the variation in soil habitats, from micro-aggregates to entire landscapes. The complexity and interdependence of soil habitats, biota diversity, and functional traits in soil are complex and poorly understood. Pre-DNA soil biodiversity assessments were limited by taxonomic knowledge of involved specialists. Nowadays by using a DNA-based approaches a representative soil sampling remains as one of main obstacles in representative soil biodiversity studies, which could be overcome with using leached water representing larger volume of soils. Soils have a water permeability/filtering ecosystem function. In its passage through soil layers water dilutes inorganic and organic elements, while its capacity for carrying eDNA remains largely unknown, despite the eDNA metabarcoding is and established approach for tracing organisms and biodiversity assessment in fresh and marine waters. An eDNA metabarcoding was also successful on bulk soils, but up to date, there is no published information on using of an eDNA approach in waters leached from soils. The proposed study aims to test four soil water related hypotheses for use of an eDNA as a soil biodiversity proxy, namely: (i) comes eDNA in water samples from lysimeters in a sufficient quantity and quality for a DNA metabarcoding-based soil biodiversity assessment; (ii) does eDNA in water samples gained from different lysimeter types yield a sufficient representation of soil communities of the target taxonomic group with a DNA metabarcoding, (iii) how distant from the lysimeter point the approach still reliably represent the soil biodiversity, and (iiii) how eDNA-assessed soil biota communities at selected taxonomic or functional levels from leached soil water change/differ with depth or soil horizons in forest, arable, and pastures land uses and if leached waters from different depths/horizons show dilution/selection/accumulation effects. Methodology approach will combine knowledge from water eDNA studies in aquatic systems, lysimeter soil water sampling approaches as used in permanent forest monitoring programmes (ICP Forests), and an eDNA metabarcoding of soil communities of archaea, bacteria, fungi, pedofauna, and plants. The eDNA metabarcoding will base on an adequate eDNA extraction from leached water followed by a sample multiplexing, and DNA metabarcoding. eDNA metabarcoding will include general markers for key soil organism kingdoms: archaea (16S rDNA), bacteria (16S rDNA), fungi (ITS rDNA), plants (rbcL or ITS2 rDNA) and animals/pedofauna (COI and optional Arth02 or Inse01 16S mt rDNA). Bioinformatics with general or adapted R scripts, and community statistics will be combined with key leached water and soil metadata (soil chemistry, isotopes, other environmental parameters) for explanation of community structure and for optimisation of sampling and eDNA treatment. The same methodology will be used in parallel with a total DNA extracted from soil cores as a reference for comparison to the eDNA samples. The experimental part of the project will end up in standardization of the final operating procedures, testing them and continuing methodological developments for specific soil types. The DNA barcoding data, supported by other relevant environmental data, will form a shared database, and will serve as the starting point for future monitoring works. The proposed operation procedure will be suggested as a monitoring approach to be included in exiting soil biodiversity programmes and reference procedures (such as ICP Forests). The national project partners team will continue networking with relevant national and international stakeholders for visibility and internationalisation of protocols (starting with the proposed international partners) and further development of specific ecosystem-adapted protocols.