Quantifying the contribution of the root system of alpine vegetation in the soil aggregate stability of moraine

One fifth of the world's population is living in mountains or in their surrounding areas. This anthropogenic pressure continues to grow with the increasing number of settlements, especially in areas connected to touristic activities, such as the Italian Alps. The process of soil formation on high mountains is particularly slow and these soils are particularly vulnerable to soil degradation. In alpine regions, extreme meteorological events are increasingly frequent due to climate change, speeding up the process of soil degradation and increasing the number of severe erosion processes, shallow landslides and debris flows. Vegetation cover plays a crucial role in the stabilization of mountain soils thereby reducing the risk of natural hazards effecting downslope areas. Soil aggregate stability is one of the main soil properties that can be linked to soil loss processes. Soils developed on moraines in recently deglaciated areas typically have low levels of soil aggregation, and a limited or discontinuous vegetation cover making them more susceptible to degradation. However, soil structure can be influenced by the root system of the vegetation. Roots are actively involved in the formation of water-stable soil aggregation, increasing the stability of the soil and its nutrient content. In the present study, we aim to quantify the effect of the root system of alpine vegetation on the soil aggregate stability of the forefield of the Lys glacier, in the Aosta Valley (NW-Italy). This proglacial area provides the opportunity to study how the root system of ten pioneer alpine species from different successional stages can contribute to soil development and soil stabilization. To quantify the aggregate stability of root permeated soils, a modified wet sieving method was employed. The root length per soil volume of the different species was also determined and later correlated with the aggregate stability results. The results showed that soil aggregate stability was significantly increased by the presence of roots. The lowest soil aggregate stability was found with Epilobium fleischeri followed by Minuartia recurva and Leucanthemopsis alpina. The highest aggregate stability was found with the graminoid species. These results show a close relationship between the development of root systems of the studied species and soil aggregate stability, a factor which can be taken into consideration in order to improve the accuracy of existing susceptibility mapping for early warning and civilian protection

Mid and long-term ecological impacts of ski run construction on alpine ecosystems

The proliferation of ski run construction is a worldwide trend. The machine-grading of slopes involved during ski run construction changes the physical, chemical and biological properties of the soil, having significant long-term ecological impact on the environment. Establishing and developing plant communities in these affected areas is crucial in rehabilitating the biotic and abiotic soil environment, while also improving slope stability and reducing the risk of natural hazards. This study evaluates changes in plant-soil properties and the long-term effects of machine-grading and subsequent restoration of ski runs so as to contribute to formulating the best practices in future ski run constructions. Study plots were established in 2000 and re-surveyed in 2017 on ski runs, which had been machine-graded and hydroseeded in the 1990s. Vegetation, root trait and soil surveys were carried out on ski run plots and compared to paired, undisturbed control sites off the ski runs. Plant cover remained unchanged on the ski-runs over time but plant richness and diversity considerably increased, reaching similar levels to undisturbed vegetation. Plant composition moved towards more semi-natural stages, showing a reduction in seeded plants with a comparable increase in the cover of colonizing native species. Root trait results were site-specific showing great variations between the mid and long-term after-effects of machine-grading and revegetation when compared to undisturbed sites. Under long-term management, the soil pH was still higher and the organic C content still lower in the ski runs than in the undisturbed sites, as the aggregate stability. The standard actions applied (machine-grading, storage and re-use of topsoil, hydroseeding of commercial seed mixtures, application of manure soon after seeding and low-intensity grazing) allowed the ecosystem to partially recover in three decades, and even if the soil has still a lower chemical and physical fertility than the undisturbed sites, the plant species composition reveals a satisfactory degree of renaturalization

Functional root trait based classification of cover crops to improve soil physical properties

Cover crop use is a well-established soil conservation technique and has been proven effective for erosion control and soil remediation in many arable systems. Whereas the obvious protection mechanism of cover crops occurs through the canopy, plant roots perform multiple functions. It is important to consider the soil functions delivered by different root systems in order to increase the uptake of cover crops for sustainable soil and water management. A classification of cover crop root systems up to 0.6 m deep based on functional traits will allow us to better study their potential role in soil bio-engineering; soil structural improvements for hydrological services and soil resource protection. A greenhouse experiment, using large 1 m3 containers filled with loam soil, loose top and compacted subsoil, in which 7 cover crop species (Oat, Rye, Buckwheat, Vetch, Radish, Mustard, Phacelia) were grown for 90 days. Root cores were taken at the end of the experiment, washed and imaged to determine root traits (total root length density, average root diameter, root specific length and root surface area) for both the top and subsoil layers. Root identity was determined from a distinctive combination of single root traits and related to 3 soil functional variables, representing soil structural improvement, runoff mitigation and erosion control. The results showed that total root length and root surface area correlate well with aggregate stability and soil macroporosity. Buckwheat, Mustard and Rye had significantly greater aggregate stability as well as 10, 8 and 7 % greater macroporosity respectively, at the interface with the compacted layer when compared to the control bare soil. Furthermore, average root diameter negatively correlated with soil macroporosity, indicating that cover crop with a fine root system are more beneficial for creating pore-space than those with thicker taproots. Selecting cover crop species with the right root traits is therefore crucial to improve soil health

Методологичен подход за изграждане на типологията на ферми от гледна точка на здравето на почвата случаят на ЕС

[EN] Soil health is a significant problem in agriculture which demands a tailor-made approach. The study aims to develop a methodological approach for farm typology construction in terms of soil health. TUdi project, under which was made this study, aims to transform unsustainable management of soils in key cropping systems in Europe and China, developing an integrated platform of alternatives to reverse soil degradation. Thus, the focus is on small, medium, and large EU farms, which produce in the three key cropping systems – grassland, cereal-based rotation, and tree crops. It was applied principal component analysis based on which it was constructed four factors, related to soil health. The results from this analysis was used to feed up the cluster analysis together with other significant variables. The developed farm typology consists of four farm types. From practical point of view was introduced a methodology which allow to determine the type of each farm according the TUdi typology.[BG] Здравето на почвата е значим проблем в аграрната икономика, които изисква прилагането на индивидуален подход. Целта на настоящата разработка е да се предложи методология за конструиране на типология на ферми, свързана със здравето на почвата. Анализът е реализиран по проект „Tudi“, който цели трансформирането на неустойчивото управление на почвите в ключови системи в Европа и Китай, разработвайки интегрирана платформа за алтернативи за обръщане на деградацията на почвата. В тази връзка фокусът е насочен към малки, средни и големи ферми от страни, членки на ЕС, които произвеждат продукция в трите ключови системи на земеделието – зърнени култури, трайни насаждения и пасища. Използван е анализ на главните компоненти за конструирането на четири фактора, свързани със здравето на почвата. Тези фактори, заедно с други ключови променливи, са анализирани чрез клъстерен анализ за формирането на четири типа ферми. Предложен е подход за определяне на мястото на всяка една ферма в тази типология.The study was developed with the financial help of the European Union’s Horizon 2020 Research and Innovation action under the project “Transforming Unsustainable management of soils in key agricultural systems in EU and China. Developing an integrated platform of alternatives to reverse soil degradation” – TUdi with grant agreement No 101000224.Peer reviewe

Methodological approach for farm typology construction in terms of soil health – the EU case

Soil health is a significant problem in agriculture which demands a tailor-made approach. The study aims to develop a methodological approach for farm typology construction in terms of soil health. TUdi project, under which was made this study, aims to transform unsustainable management of soils in key cropping systems in Europe and China, developing an integrated platform of alternatives to reverse soil degradation. Thus, the focus is on small, medium, and large EU farms, which produce in the three key cropping systems - grassland, cereal-based rotation, and tree crops. It was applied principal component analysis based on which it was constructed four factors, related to soil health. The results from this analysis was used to feed up the cluster analysis together with other significant variables. The developed farm typology consists of four farm types. From practical point of view was introduced a methodology which allow to determine the type of each farm according the TUdi typology