Changes of Water Budget during Ecosystem Development in Post-Mining Sites at Various Spatiotemporal Scales: The Need for Controlled Systems

This chapter describes the development of the soil-water budget at various spatiotemporal scales, including an example of post-mining sites. This includes the formation of soil aggregates and porosity, the development of water retention in the soil profile, and water losses by runoff and evapotranspiration. It is emphasized that the development of soil-water retention is closely linked to carbon storage in post-mining soils, which is strongly affected by litter quality. Plants with a high C:N ratio of litter feature most of the organic matter in Oe and litter layers, which results in a lower soil-water storage, whereas soil covered by vegetation with low litter C:N ratios produces organo-mineral aggregates and deeper A horizons that promote water storage. Moreover, the need for controlled catchment conditions to get a better understanding of how these processes on various spatiotemporal scales interact is emphasized

Tree species identity alters decomposition of understory litter and associated microbial communities : a case study

Investigations on how tree species modify decomposition of understory litter have rarely been conducted, although potentially having impacts on soil carbon stocks and stability. The aim of our study was to disentangle the effects different tree species (alder, spruce, oak, and willow) exert on litter decomposition by comparing decomposition patterns and microbial measures (phospholipid fatty acids and microbial DNA) of both tree and understory (Calamagrostis epigejos) litter exposed at the respective tree species stands of a common garden experiment. An initially uniform mass loss of understory litter exposed at the stands suggests that inherent litter quality (assessed by C:N ratios and lignin content) was the major driver in early decomposition. However, in later stages of our experiment, decomposition of understory litter began to differ among the stands, suggesting a delayed tree species effect. Here, differences in microbial community composition caused by tree species identity (e.g., through varying N supply or phenolics leached from low-quality litter) were likely the major determinants affecting the decomposition of understory litter. However, in these advanced decomposition stages, tree species identity only partly altered microbial communities associated with understory litter. These results indicate that the development of microbial communities on understory litter (and its decay) is likely a combined result of inherent chemical composition and tree species identity.Peer reviewe

The effect of underground drainage on peat meadows and inactivation of the drainage in an attempt to restore these meadows, which failed as it reduced the ability of soils to retain water

Drainage is often used to increase agriculture production, but it has adverse effects on biodiversity and water retention. Here, the effect of subsurface pipe drainage on peat meadows near Senotín (Czechia), which were drained from the mid-1980s to 1990s, was studied. Attempts were made to restore the peat meadows by damming drainage pipes using clay-filled trenches in 1996. In this case study, the effect on the depth of the water table, soil water retention, infiltration and soil temperature were recorded. Measurements of the original peat meadow (undrained site), drained meadow (drained site) and restored meadow (restored site) before restoration and two decades after restoration were recorded. The water table in undrained areas was higher than at drained and restored sites, indicating that drainage had lasting effect on drained and restored sites. Infiltration was lowest at the undrained site, greater at the drained site, and highest at the restored sites. Field water capacity was lowest at the restored site, greater at the drained site and highest at the undrained site. Soil water content at maximum saturation was lowest at the restored site, greater at the drained site and highest at the undrained site. Soil temperature was highest at the restored site with no significant difference between the undrained and drained sites. Soil moisture levels were highest at the undrained site and lowest at the drained site. In addition, the undrained and restored sites did not differ significantly in soil moisture content. In conclusion, restoration did not have a significant effect on the level of the water table, initiation of peat formation or ability of soil to hold water

Plant Communities Rather than Soil Properties Structure Arbuscular Mycorrhizal Fungal Communities along Primary Succession on a Mine Spoil

Arbuscular mycorrhizal fungal (AMF) community assembly during primary succession has so far received little attention. It remains therefore unclear, which of the factors, driving AMF community composition, are important during ecosystem development. We addressed this question on a large spoil heap, which provides a mosaic of sites in different successional stages under different managements. We selected 24 sites of c. 12, 20, 30, or 50 years in age, including sites with spontaneously developing vegetation and sites reclaimed by alder plantations. On each site, we sampled twice a year roots of the perennial rhizomatous grass Calamagrostis epigejos (Poaceae) to determine AMF root colonization and diversity (using 454-sequencing), determined the soil chemical properties and composition of plant communities. AMF taxa richness was unaffected by site age, but AMF composition variation increased along the chronosequences. AMF communities were unaffected by soil chemistry, but related to the composition of neighboring plant communities of the sampled C. epigejos plants. In contrast, the plant communities of the sites were more distinctively structured than the AMF communities along the four successional stages. We conclude that AMF and plant community successions respond to different factors. AMF communities seem to be influenced by biotic rather than by abiotic factors and to diverge with successional age

Microbial communities in local and transplanted soils along a latitudinal gradient

Factors shaping community structure of soil microbiota have been intensively studied; however, the pattern in community composition and structure of soil microbiota at large geographical scales and factors regulating its metabolic activity remains poorly understood. Here, we used a field transplantation experiments to investigate the effects of substrate and climatic conditions on basal soil respiration, microbial biomass C and diversity of soil microbiota by comparing local and transplanted soils along a latitudinal gradient. Soil samples collected in April 2008 at donor site (Sokolov, Czech Republic) in Central Europe were gamma-ray sterilized and transplanted to receptor sites in Europe and the USA in May and early June 2008. Soil samples were taken in June 2009 after one year of exposure and immediately prepared for laboratory analysis. Basal soil respiration in local soils increased from 22 to 42 mg CO2-C kg-1 h-1 with latitude while basal soil respiration in transplanted soils decreased with latitude from 32 to 19 mg CO2-C kg-1 h-1. The microbial biomass C in both transplanted and local soils decreased with latitude. Content of fungal and bacterial phospholipid fatty acids increased nearly twice with latitude in local soils. Shannon diversity index of fungal community decreased from 2.5 to 1.2 along the latitudinal gradient in transplanted soils while local soils increased from 0.9 to 2.4 with latitude. Based on our results, microbial activity is driven mainly by changes of the soil substrate along latitudinal and climatic gradients while microbial biomass is driven more by global climatic factors itself. The diversity of soil microbial communities is mostly affected by latitudinal and climatic factors while community structure is mostly shaped by substrate quality

Challenges and a call to action for protecting European red wood ants

Red wood ants (RWAs) are a group of keystone species widespread in temperate and boreal forests of the Northern Hemisphere. Despite this, there is increasing evidence of local declines and extinctions. We reviewed the current protection status of RWAs throughout Europe and their International Union for the Conservation of Nature (IUCN) threat classification. Only some RWA species have been assessed at a global scale, and not all national red lists of the countries where RWAs are present include these species. Different assessment criteria, inventory approaches, and risk categories are used in different countries, and data deficiency is frequent. Legislative protection is even more complex, with some countries protecting RWAs implicitly together with the wildlife fauna and others explicitly protecting the whole group or particular species. This complexity often occurs within countries, for example, in Italy, where, outside of the Alps, only the introduced species are protected, whereas the native species, which are in decline, are not. Therefore, an international, coordinated framework is needed for the protection of RWAs. This first requires that the conservation target should be defined. Due to the similar morphology, complex taxonomy, and frequent hybridization, protecting the entire RWA group seems a more efficient strategy than protecting single species, although with a distinction between autochthonous and introduced species. Second, an update of the current distribution of RWA species is needed throughout Europe. Third, a protection law cannot be effective without the collaboration of forest managers, whose activity influences RWA habitat. Finally, RWA mounds offer a peculiar microhabitat, hosting a multitude of taxa, some of which are obligate myrmecophilous species on the IUCN Red List. Therefore, RWAs' role as umbrella species could facilitate their protection if they are considered not only as target species but also as providers of species-rich microhabitats

Smart strategies for the transition in coal intensive regions

The TRACER project supports a number of coal-intensive regions around Europe to design (or re-design) their Research and Innovation (R&I) strategies in order to facilitate their transition towards a sustainable energy system. The TRACER consortium consists of different target regions: South East Bulgaria, North West Bohemia - Czech Republic, Lusatian Lignite District - Germany, Western Macedonia - Greece, Upper Silesian Coalfield - Poland, West Region, Jiu Valley - Romania, Wales – UK, Kolubara - Serbia, Donetsk - Ukraine. Core activities of TRACER include the implementation of an EDP (Entrepreneurial Discovery Process) to mobilise a wide range of stakeholders in each target region to develop an appropriate governance structure and to bring regional stakeholders together to discuss and agree on a shared vision and priorities for coal transition. R&I strategies, industrial roadmaps and decision support tools will be developed jointly with key stakeholders of the TRACER target regions. Further TRACER activities include the identification and analysis of best practice examples of successful and ambitious transition processes in coal intensive regions, a detailed assessment of social, environmental and technological challenges, the elaboration of guidelines on how to mobilise investment as well as dedicated activities to stimulate R&I cooperation among coal intensive regions in Europe and beyond

KEYLINK: towards a more integrative soil representation for inclusion in ecosystem scale models. I. review and model concept

The relatively poor simulation of the below-ground processes is a severe drawback for many ecosystem models, especially when predicting responses to climate change and management. For a meaningful estimation of ecosystem production and the cycling of water, energy, nutrients and carbon, the integration of soil processes and the exchanges at the surface is crucial. It is increasingly recognized that soil biota play an important role in soil organic carbon and nutrient cycling, shaping soil structure and hydrological properties through their activity, and in water and nutrient uptake by plants through mycorrhizal processes. In this article, we review the main soil biological actors (microbiota, fauna and roots) and their effects on soil functioning. We review to what extent they have been included in soil models and propose which of them could be included in ecosystem models. We show that the model representation of the soil food web, the impact of soil ecosystem engineers on soil structure and the related effects on hydrology and soil organic matter (SOM) stabilization are key issues in improving ecosystem-scale soil representation in models. Finally, we describe a new core model concept (KEYLINK) that integrates insights from SOM models, structural models and food web models to simulate the living soil at an ecosystem scale