LUCAS 2018 - SOIL COMPONENT: Sampling Instructions for Surveyors

The European Commission launched a soil assessment component to the periodic LUCAS Land Use/Land Cover Area Frame Survey in 2009. Composite soil samples from 0-20-cm depth were taken, air-dried and sieved to 2 mm in order to analyse physical and chemical parameters of topsoil in 25 Member States (EU-27 except Bulgaria, Romania, Malta and Cyprus). The aim of the LUCAS Soil Component was to create a harmonised and comparable dataset of main properties of topsoil at the EU. The LUCAS Soil Component was extended to Bulgaria and Romania in 2012. Overall, ca. 22,000 soil samples were collected and analysed. All samples were analysed for percentage of coarse fragments, particle-size distribution, pH, organic carbon, carbonates, phosphorous, total nitrogen, extractable potassium, cation exchange capacity, multispectral properties and heavy metals. In 2015, the soil sampling was repeated in the same set of points of LUCAS 2009/2012 to monitor changes in topsoil physical and chemical parameters across the EU. The soil component was extended to points above elevations of 1000 m, which were not sampled in LUCAS 2009/2012. Furthermore, soil samples were taken in Albania, Bosnia-Herzegovina, Croatia, Macedonia, Montenegro, Serbia and Switzerland. The soil sampling was carried out following the instructions already used in LUCAS 2009/2012. Approximately 27,000 samples were collected and will be analysed during 2016 and 2017. In 2018, a new soil sampling campaign will be carried out within the LUCAS framework. Soil samples will be taken in repeated points of LUCAS 2009/2012 and LUCAS 2015. The novelty of the survey is that new physical, chemical and biological parameters will be analysed. Key parameters for evaluating soil quality, such as bulk density and soil biodiversity, will be analysed. These analyses require specific methods of soil sampling, preparation and storage of samples. Furthermore, field measurements such as the thickness of organic layer in peat soils, and visual assessment of signs of soil erosion will be carried out in 2018. This technical report compiles the instructions for collecting the various soil samples and for performing field measurements in the soil survey of 2018. These instructions will be used for all LUCAS surveyors, to create a comparable database of soil characteristics all over Europe.JRC.D.3-Land Resource

Arbuscular Mycorrhizal Fungi and their Value for Ecosystem Management

Arbuscular Mycorrhizal Fungi (AMF) are root obligate symbionts of nearly all the plants living on Earth. They are considered as living fossils: there are evidences that date back to 460 million years ago their presence on our planet. Taxonomically, they belong to the Glomeromycota phylum. They are found in roots of 80% of plant species and give and get back benefits to their partners, as happens in all mutual symbiotic relationships. They build up a bridge between plant and soil, growing their mycelia both inside and outside plant roots. AMF provide the plant with water, soil mineral nutrients (mainly phosphorus and nitrogen), and pathogen protection. In exchange, photosynthetic compounds are transferred to the fungus. Besides physiological benefits to the host-plant, AMF play an important ecological role. They are important in soil structuring thanks to their thick extraradical hyphal network able to aggregate soil particles. They help plants establish in degraded ecosystems (e.g. desert areas and mine spoils) and positively affect phytoremediation. They can influence processes (i.e. soil carbon sequestration) related to climate change. Last but not least, their belowground presence and diversity can positively affect the aboveground plant biodiversity and productivity. These roles played by AMF for the ecosystem functioning lead to consider them as key soil organisms. Therefore, every AMF aspect is extensively studied: from biological features, through biogeography and biodiversity, to phylogeny. [...]JRC.H.5-Land Resources Managemen

A knowledge-based approach to estimating the magnitude and spatial patterns of potential threats to soil biodiversity

AbstractBecause of the increasing pressures exerted on soil, below-ground life is under threat. Knowledge-based rankings of potential threats to different components of soil biodiversity were developed in order to assess the spatial distribution of threats on a European scale. A list of 13 potential threats to soil biodiversity was proposed to experts with different backgrounds in order to assess the potential for three major components of soil biodiversity: soil microorganisms, fauna, and biological functions. This approach allowed us to obtain knowledge-based rankings of threats. These classifications formed the basis for the development of indices through an additive aggregation model that, along with ad-hoc proxies for each pressure, allowed us to preliminarily assess the spatial patterns of potential threats. Intensive exploitation was identified as the highest pressure. In contrast, the use of genetically modified organisms in agriculture was considered as the threat with least potential. The potential impact of climate change showed the highest uncertainty. Fourteen out of the 27 considered countries have more than 40% of their soils with moderate-high to high potential risk for all three components of soil biodiversity. Arable soils are the most exposed to pressures. Soils within the boreal biogeographic region showed the lowest risk potential. The majority of soils at risk are outside the boundaries of protected areas. First maps of risks to three components of soil biodiversity based on the current scientific knowledge were developed. Despite the intrinsic limits of knowledge-based assessments, a remarkable potential risk to soil biodiversity was observed. Guidelines to preliminarily identify and circumscribe soils potentially at risk are provided. This approach may be used in future research to assess threat at both local and global scale and identify areas of possible risk and, subsequently, design appropriate strategies for monitoring and protection of soil biota

Pyrosequencing analysis of fungal assemblages from geographically distant, disparate soils reveals spatial patterning and a core mycobiome

Identifying a soil core microbiome is crucial to appreciate the established microbial consortium, which is not usually subjected to change and, hence, possibly resistant/resilient to disturbances and a varying soil context. Fungi are a major part of soil biodiversity, yet the mechanisms driving their large-scale ecological ranges and distribution are poorly understood. The degree of fungal community overlap among 16 soil samples from distinct ecosystems and distant geographic localities (truffle grounds, a Mediterranean agro-silvo-pastoral system, serpentine substrates and a contaminated industrial area) was assessed by examining the distribution of fungal ITS1 and ITS2 sequences in a dataset of 454 libraries. ITS1 and ITS2 sequences were assigned to 1,660 and 1,393 Operational Taxonomic Units (OTUs; as defined by 97% sequence similarity), respectively. Fungal beta-diversity was found to be spatially autocorrelated. At the level of individual OTUs, eight ITS1 and seven ITS2 OTUs were found in all soil sample groups. These ubiquitous taxa comprised generalist fungi with oligotrophic and chitinolytic abilities, suggesting that a stable core of fungi across the complex soil fungal assemblages is either endowed with the capacity of sustained development in the nutrient-poor soil conditions or with the ability to exploit organic resources (such as chitin) universally distributed in soils

Ecosystem type drives soil eukaryotic diversity and composition in Europe

Soil eukaryotes play a crucial role in maintaining ecosystem functions and services, yet the factors driving their diversity and distribution remain poorly understood. While many studies focus on some eukaryotic groups (mostly fungi), they are limited in their spatial scale. Here, we analyzed an unprecedented amount of observational data of soil eukaryomes at continental scale (787 sites across Europe) to gain further insights into the impact of a wide range of environmental conditions (climatic and edaphic) on their community composition and structure. We found that the diversity of fungi, protists, rotifers, tardigrades, nematodes, arthropods, and annelids was predominantly shaped by ecosystem type (annual and permanent croplands, managed and unmanaged grasslands, coniferous and broadleaved woodlands), and higher diversity of fungi, protists, nematodes, arthropods, and annelids was observed in croplands than in less intensively managed systems, such as coniferous and broadleaved woodlands. Also in croplands, we found more specialized eukaryotes, while the composition between croplands was more homogeneous compared to the composition of other ecosystems. The observed high proportion of overlapping taxa between ecosystems also indicates that DNA has accumulated from previous land uses, hence mimicking the land transformations occurring in Europe in the last decades. This strong ecosystem-type influence was linked to soil properties, and particularly, soil pH was driving the richness of fungi, rotifers, and annelids, while plant-available phosphorus drove the richness of protists, tardigrades, and nematodes. Furthermore, the soil organic carbon to total nitrogen ratio crucially explained the richness of fungi, protists, nematodes, and arthropods, possibly linked to decades of agricultural inputs. Our results highlighted the importance of long-term environmental variables rather than variables measured at the time of the sampling in shaping soil eukaryotic communities, which reinforces the need to include those variables in addition to ecosystem type in future monitoring programs and conservation efforts.Collaborative Doctoral Partnership JRC and Universidade de Vigo | Ref. n. 35533Universidade de Vigo/CISUG | Ref. acceso abiert

Soil erosion is unlikely to drive a future carbon sink in Europe

Acknowledgements: The work was carried out as part of the JRC's Institutional Work Programme under the Natural Capital Soil Project (Project 702), Work Package 5037 “Soil for Climate Change”. We thank Irene Biavetti for her graphical support in designing Fig. 2. Data and materials availability: All data needed to evaluate the conclusions in the paper are available at the European Soil Data Centre (ESDAC) of the European Commission – Joint Research Centre: http://esdac.jrc.ec.europa.eu/. Additional data related to this paper may be requested from the authors.Peer reviewedPublisher PD

Challenges of and opportunities for protecting European soil biodiversity

Soil biodiversity and related ecosystem functions are neglected in most biodiversity assessments and nature conservation actions. We examined how society, and particularly policy makers, have addressed these factors worldwide with a focus on Europe and explored the role of soils in nature conservation in Germany as an example. We reviewed past and current global and European policies, compared soil ecosystem functioning in- and outside protected areas, and examined the role of soils in nature conservation management via text analyses. Protection and conservation of soil biodiversity and soil ecosystem functioning have been insufficient. Soil-related policies are unenforceable and lack soil biodiversity conservation goals, focusing instead on other environmental objectives. We found no evidence of positive effects of current nature conservation measures in multiple soil ecosystem functions in Europe. In German conservation management, soils are considered only from a limited perspective (e.g., as physicochemical part of the environment and as habitat for aboveground organisms). By exploring policy, evidence, and management as it relates to soil ecosystems, we suggest an integrative perspective to move nature conservation toward targeting soil ecosystems directly (e.g., by setting baselines, monitoring soil threats, and establishing a soil indicator system)

Climate change and cropland management compromise soil integrity and multifunctionality

Soils provide essential ecosystem functions that are threatened by climate change and intensified land use. We explore how climate and land use impact multiple soil function simultaneously, employing two datasets: (1) observational – 456 samples from the European Land Use/Land Cover Area Frame Survey; and (2) experimental – 80 samples from Germany’s Global Change Experimental Facility. We aim to investigate whether manipulative field experiment results align with observable climate, land use, and soil multifunctionality trends across Europe, measuring seven ecosystem functions to calculate soil multifunctionality. The observational data showed Europe-wide declines in soil multifunctionality under rising temperatures and dry conditions, worsened by cropland management. Our experimental data confirmed these relationships, suggesting that changes in climate will reduce soil multifunctionality across croplands and grasslands. Land use changes from grasslands to croplands threaten the integrity of soil systems, and enhancing soil multifunctionality in arable systems is key to maintain multifunctionality in a changing climate