•Non-grazing rangelands improved litter quality rather than grazing sites.•A. aucheri litter decomposed faster than litter of A. podolobus and E. lanata.•Litter decomposition was highest at the ...non-grazing woody rangeland.•Continuous grazing resulted in a decrease of microbial C and N decomposition in rangeland soils.•Presence of woody species in rangelands improved soil fertility and productivity.
The effects of rangeland management on biogeochemical processes that control the exchange of C and nutrients between the soil and plant are not well understood. For this purpose, aboveground litter properties and decomposition of three dominant species (Artemisia aucheri, Astragalus podolobus, and Eurotia lanata) were studied in four rangeland management systems of northern Iran including continuous grazing, intermittent grazing, and two non-grazing sites (i.e. woody and non-woody rangelands). We tested the following hypotheses: (i) woody rangeland improves litter quality, with a higher rate of decomposition, soil fertility and biochemical functions compared to non-woody rangeland and grazed sites, and (ii) continuous grazing reduces microbial C and N turnover. Plant residues from all rangeland species in the grazing and non-grazing areas were collected and soil samples were taken and analyzed for chemical properties and microbial activities. Based on the obtained data, litter decomposition was faster under woody rangeland ecosystem (Artemisia aucheri > Astragalus podolobus > Eurotia lanata) compared with the other study sites. The results revealed improved litter quality and increased soil available nutrients, as well as C and N mineralization for the woody rangeland, whereas under intermittent grazing the soil C/N ratio, microbial basal respiration (BR), substrate induced respiration (SIR) and microbial biomass C (MBC) increased. Soil pH, EC, qCO2 (BR: MBC) were significantly higher under continuous grazing, but with lower contents of soil organic C, total N, and available Mg. Furthermore, C and N stocks, microbial entropy (MBC: organic C), C availability index (BR: SIR), particulate organic matter C, dissolved organic C, mineral N (i.e., NH4 and NO3), microbial biomass N, particulate organic matter N and dissolved organic N were decreased in the continuous grazing site. Thus, we concluded that continuous grazing might depress soil C and N microbial activity, but woody rangeland could improve soil quality.
Soils and their functions are critical to ensure the provision of various ecosystem services (ES). Many authors nevertheless argue that there are a lack of satisfactory operational methods for ...quantifying the contributions of soils to the supply of ES. In this study, we review ES mapping studies that have taken the roles of soils in ES supply into account, and propose soil function assessment (SFA) methods approved by German Federal States in spatial planning procedures to use in assessments of ES supply. We found 181 ES mapping studies in which the roles of soils in ES supply were considered. At least one soil property was used as an indicator of soil-related ES in 60% of the publications, and 13% of the publications were mainly focused on the roles of soils in supplying ES. More than two soil functions were considered in a minority of cases, indicating that the multi-functionality of soils has barely been taken into account in previous ES studies. Several decades ago, the soil science community has adopted the concept of soil functions to bring different aspects of soil to the fore and to emphasize the multi-functionalities of soils and their vastly different chemical, physical, and biological properties. We provide a set of approved SFA methods that cover the multi-functionalities of soils and are applicable to ES supply assessments. We propose that this set of operational SFA methods is a starting point for quantifying how soil systems underpin the supply of a wide range of ES. The minimal soil dataset required for these SFA methods is relatively small, and much progress has been made nationally and globally over the last decade in improving soil data infrastructure and online access for end users. These improvements will facilitate the incorporation of SFA into ES studies and thereby improve information for land use decisions. We recommend that ES assessments include the essential and multifunctional roles of soils to promote sustainable land use.
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•The study aimed to reveal farmers’ perception of the soil functions’ importance.•The results indicated that “Ensure productivity” function received the highest importance.•The “Water ...quantity regulation” and “Water quality maintenance and enhancement” functions predicted the use of compost.•It was concluded that the perceived importance of water-related soil functions can stimulate the use of compost.•The study recommended that older farmers should be targeted by awareness campaigns to stimulate them to use compost.
Agriculture is a key player in the conservation of natural resources and cultural landscapes and one of the most prominent interfaces between human activity and soil. The present paper reveals a social perspective on soil functions. In this context, it was assumed that perceptions of soil functions could transform themselves into components of agro-ecosystems and influence the whole decision-making process. Therefore, it is indispensable to look at farmers when approaching soil functions. The objective of this study was twofold. Firstly, Romanian farmers’ perception of the importance of soil functions was investigated. Secondly, it was revealed how well farmers’ perception of soil functions importance and socio-economic variables could predict the “Use of compost”. Soil functions were selected based on an extensive literature review. Farmers’ perceptions of soil functions and the use of compost as a measure taken to improve soil productivity were studied through a questionnaire applied to a sample of 278 Romanian farmers randomly selected from sixteen villages. Binary logistic regression revealed that the perceived importance of two soil functions could predict the use of compost – “Water quantity regulation” and “Water quality maintenance and enhancement”. The study concluded that strengthening the importance of the “Water quantity regulation” function in farmers’ minds can stimulate the use of compost. It was also inferred that because younger farmers are more prone to composting, they will be more receptive to marketing actions related to compost use, such as the acquisitions of materials and instruments useful for compost production and use. In a context where a real dialogue to elaborate well-grounded environmental policies is still elusive because of differences between farmers and policy-makers’ views, investigation of farmers’ perceptions can bring a significant contribution towards a bottom-up approach for sustainable soil management.
Soil biota contribute to the delivery of multiple soil functions. However, soil biological methods are highly underrepresented in the assessment of soil functionality in agricultural production ...systems. Here we present a flexible tool to support decision-making during the selection process of soil biological methods for monitoring soil functions. This tool is based on a structured and conceptual framework that connects soil biota to soil functions through their contribution to different soil processes. The methods assessed by the tool were selected as a result of a thorough literature review. Soil biology experts supported the development of the tool (i) by providing feedback on the reviewed methods through a survey and (ii) by determining the relevance of different soil biota to the soil processes related to soil multifunctionality during a workshop. The tool is freely accessible online at the Biological Soil Information System (BIOSIS) platform, where researchers or users with an understanding of research practices can interact with the tool to define the context of their assessment and preferences for technical criteria of the methods. By incorporating user input, this flexible tool can help inform a wide variety of research and assessment programs interested in applying soil biological methods to monitor soil multifunctionality at different scales.
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•We developed a tool for selecting biological methods to assess soil functions.•The tool is freely accessible online at the BIOSIS platform.•The BIOSIS tool is flexible to consider context-specific requirements of users.•The transparent setup of the tool allows for further development and collaboration.
The structure of compacted soils is characterised by decreased (macro-)porosity, which leads to increased mechanical impedance and decreased fluid transport rates, resulting in reduced root growth ...and crop productivity. Particularly in soils with high mechanical impedance, macropores can be used by roots as pathways of least resistance. This study investigated how different soil physical states relate to whole plant growth and whether roots grow towards spots with favourable soil physical conditions. Experiments were conducted under controlled and field conditions. Soybean (Glycine max L.), wheat (Triticum aestivum L.) and maize (Zea mays L.) were grown on uncompacted soil, compacted soil and compacted soil with artificial macropores. The interactions between roots and artificial macropores were quantified using X-ray computed tomography. Active growth of roots towards artificial macropores was observed for all three species. Roots grew either into macropores (predominantly in maize) or crossed them (predominantly in wheat). The presence of artificial macropores in compacted soil enabled all three species to compensate for decreased early vigour at later developmental stages. These results show that roots sense their physical environment, enabling them to grow towards spots with favourable soil conditions. The different kinds of root-macropore interaction indicated that macropores serve as a path of least resistance and a source of oxygen, both resulting in increased crop productivity on compacted soils.
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•Artificial macropores restore certain soil physical functions of compacted soils.•Crop roots preferentially grow towards artificial macropores in compacted soil.•Artificial macropores provide different functions for roots in compacted soil.•Artificial macropores increase soil fertility and crop growth in compacted soil.
The contribution of soil health to global health receives a growing interest, especially in urban environment. Therefore, there is a true need to develop methods to evaluate ecological functions ...provided by urban soils in order to promote smart urban planning. This work aims first at identifying relevant soil indicators based either on in situ description, in situ measurement or lab analysis. Then, 9 soil functions and sub-functions were selected to meet the main expectations regarding soil health in urban contexts. A crucial step of the present research was then to select adequate indicators for each soil function and then to create adapted reference frameworks; they were in the form of 4 classes with scores ranging from 0 to 3. All the reference frameworks were developed to evaluate soil indicators in order to score soil functions, either by using existing scientific or technical standards or references or based on the expertise of the co-authors. Our model was later tested on an original database of 109 different urban soils located in 7 cities of Western Europe and under various land uses. The scores calculated for 8 soil functions of 109 soils followed a Gaussian distribution. The scoring successfully expressed the strong contrasts between the various soils; the lowest scores were calculated for sealed soils and soils located in urban brownfields, whereas the highest were found for soils located in city parks or urban agriculture. Despite requiring a soil expertise, the proposed approach is easy to implement and could help reveal the true potential of urban soils in order to promote smart urban planning and enhance their contribution to global health.
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•Bio-physico-chemical soil parameters and reference frameworks were associated to create indicators of urban soil health•29 soil indicators were combined to model 9 soil functions in connexion with the specific issues of urban environment•An original database of 109 urban soils with various land uses was created to test the model.•The urban soil function scores accurately reflected the differences in soil health.
In order to meet constantly increasing demands for land without damaging pristine environments like forests or grasslands, reclamation and re-purposing of historically contaminated areas should ...become a priority. Successful reclamation goes hand in hand with the soil functional recovery potential and with resilient microbial communities capable of performing the necessary ecosystem services. In this context, we designed a greenhouse pot experiment as a mock reclamation situation, where traces of lindane at hazard threshold and twice the concentration accepted for waste deposits are left in the soil after conventional clean-up by excavation and land filling. We assessed the effects of lindane at 50 and 100 mg kg−1 regarding crop growth and nutrient turnover (with focus on the nitrogen cycle) as two key parameters for soil functions. The bulk and rhizosphere soil bacterial community composition were chosen as parameters for soil resilience in lindane contamination conditions. Lindane severely affected plant growth and development. The potential nitrogen fixation, quantified as nifH gene copy number, suffered direct negative effects of lindane contamination in bulk soil, which could represent an additional obstacle for phytoremediation. Changes in rhizosphere bacterial community composition were related to lindane toxic effects towards the plants, which might have supported the growth of opportunists and saprophytes. In bulk soil, the bacterial community shifted towards lindane tolerant taxa like Sphingomonas and Porphyrobacter that are interesting with regard to their applications in bioremediation. We concluded that lindane at hazard threshold concentration left in soil after clean-up has negative effects both soil functionality, and the recovery of the bacterial communities to their original composition when lindane resistant plant crops are not involved.
•Lindane at 50 and 100 mg kg−1 negatively affects growth and development of barley.•Lower nitrogen fixation potential (nifH gene abundance) in contaminated bulk soil•High exudation in contaminated rhizosphere supports growth of opportunistic bacteria.•Bulk soil bacterial community shifts towards lindane tolerant taxa.
Thinning is a widely-used management practice to reduce tree competition and improve wood production and quality in forest plantations. Thinning affects the soil ecosystem by changing the ...microclimate and plant growth, as well as litter inputs above and belowground, with all the resulting consequences for microbial communities and functions. Although many case studies have been carried out, a comprehensive understanding of the thinning effects on soil properties and microbial communities and functions in plantations remains to be explored. In this study, a meta-analysis was performed on 533 paired observations based on 90 peer-reviewed articles to evaluate the general responses of soil (mainly 0–20 cm depth) physicochemical properties, microbial biomass and community structure, and enzyme activities to thinning. Results showed that thinning increased soil temperature (13 %), moisture (8.0 %), electric conductivity (13 %), and the contents of total nitrogen (TN, 4.1 %), dissolved organic carbon (DOC, 9.7 %), nitrate N (NO3−–N, 27 %) and available phosphorous (22 %). For microbial properties, thinning decreased the fungi to bacteria ratio (F:B, −28 %) and the gram-positive bacteria to gram-negative bacteria ratio (G+:G−, −12 %), while increased microbial biomass C (7.1 %), microbial respiration (13 %), and nutrient-cycle related enzyme activities, including phenol oxidase (14 %), cellobiohydrolase (21 %), urease (10 %), and acid phosphatase (9 %). In particular, moderate thinning (30–60 % intensity) has higher conservation benefits for soil C and nutrients than light and heavy intensity, thus being recommended as the optimal thinning activity. This meta-analysis suggests that thinning consistently altered soil properties, shifted microbial community compositions from K- to-r strategist dominance, and stimulated microbial activities. These results are essential for optimizing plantation thinning management and provide evidence for applying the macro-ecology theory to ecosystem disturbance in soil microbial ecology.
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•Plantations thinning effects on soil and microbe were evaluated by meta-analysis.•Thinning increased total N while had no effects on SOC thus reduced the C:N ratio.•Moderate thinning (30 %–60 % intensity) profoundly increased available N and P.•Thinning shifted microbial community from the dominance of K- to r-strategists.•Thinning strongly stimulated microbial respiration and enzyme activities.
Cover crops in vineyards do provide many important ecosystem functions, however wine growers are often reluctant to incorporate cover crops into their vineyard management as they are concerned about ...competition regarding water and nutrient availability. The objective of this study was to define the effects of three standard inter-row vegetation management strategies on vine growth and grape quality in different European regions. We hypothesize that general patterns of responses to different inter-row management can be identified across European vine growing regions independent of local climate and soil conditions. Data were collected in 2016 and 2017 in commercial vineyards located in five European temperate wine growing regions directly comparing standard inter-row vegetation management strategies in parallel in vineyards ranging from cover crops to bare ground through tillage or herbicide application. Vegetation management strongly influenced leaf chlorophyll content, shoot pruning weight and yeast assimilable nitrogen (YAN) in grape juice. Across countries, grape varieties and varying soil conditions, YAN consistently showed higher values in grapes separated by bare ground inter-rows as compared to inter-rows with a permanent vegetation cover. Other grape quality parameters, total soluble solids, total titratable acidity and berry weight were not or inconsistently affected across countries, preventing the prediction of generalized trends. We also observed higher values of soil organic matter in complete vegetation inter-rows. In conclusion, we identified general effects of inter-row vegetation management on vine vigor and grape quality across countries and grape varieties in different pedo-climatic conditions. Our study provides general response patterns as a basis for functional studies to develop local inter-row vegetation management strategies.
•Across European vineyards, inter-row vegetation decreased vine vigor and grape nitrogen.•Vine response was conserved across pedo-climatic conditions and grape varieties.•Pruning weight and leaf chlorophyll content increased with soil tillage.•Total soluble solids and titratable acidity were not influenced by inter-row management.•Soil organic matter decreased with soil tillage or herbicide application.
Feeding the world population, 7.3 billion in 2015 and projected to increase to 9.5 billion by 2050, necessitates an increase in agricultural production of ~70% between 2005 and 2050. Soil ...degradation, characterized by decline in quality and decrease in ecosystem goods and services, is a major constraint to achieving the required increase in agricultural production. Soil is a non-renewable resource on human time scales with its vulnerability to degradation depending on complex interactions between processes, factors and causes occurring at a range of spatial and temporal scales. Among the major soil degradation processes are accelerated erosion, depletion of the soil organic carbon (SOC) pool and loss in biodiversity, loss of soil fertility and elemental imbalance, acidification and salinization. Soil degradation trends can be reversed by conversion to a restorative land use and adoption of recommended management practices. The strategy is to minimize soil erosion, create positive SOC and N budgets, enhance activity and species diversity of soil biota (micro, meso, and macro), and improve structural stability and pore geometry. Improving soil quality (i.e., increasing SOC pool, improving soil structure, enhancing soil fertility) can reduce risks of soil degradation (physical, chemical, biological and ecological) while improving the environment. Increasing the SOC pool to above the critical level (10 to 15 g/kg) is essential to set-in-motion the restorative trends. Site-specific techniques of restoring soil quality include conservation agriculture, integrated nutrient management, continuous vegetative cover such as residue mulch and cover cropping, and controlled grazing at appropriate stocking rates. The strategy is to produce "more from less" by reducing losses and increasing soil, water, and nutrient use efficiency.
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