Assessment of promising agricultural management practices

iSQAPER project - Interactive Soil Quality Assessment in Europe and China for Agricultural Productivity and Environmental Resilience - aims to develop an app to advise farmers on selecting the best AgricultureManagement Practice (AMPs) to improve soil quality. For this purpose, a soil quality index has to be developed to account for the changes in soil quality as impacted by the implementation of the AMPs. Some promising AMPs have been suggested over the time to prevent soil degradation. These practices have been randomly adopted by farmers but which practices are most used by farmers and where they are mostly adopted remains unclear. This study is part of the iSQAPER project with the specific aims: 1) map the current distribution of previously selected 18 promising AMPs in several pedo-climatic regions and farming systems located in ten and four study site areas (SSA) along Europe and China, respectively; and 2) identify the soil threats occurring in those areas. In each SSA, farmers using promising AMP'swere identified and questionnaires were used to assess farmer's perception on soil threats significance in the area. 138 plots/farms using 18 promising AMPs, were identified in Europe (112) and China (26).Results show that promising AMPs used in Europe are Crop rotation (15%), Manuring & Composting (15%) and Min-till (14%), whereas in China areManuring & Composting (18%), Residuemaintenance (18%) and Integrated pest and disease management (12%). In Europe, soil erosion is the main threat in agricultural Mediterranean areas while soilborne pests and diseases is more frequent in the SSAs from France and The Netherlands. In China, soil erosion, SOM decline, compaction and poor soil structure are among the most significant. This work provides important information for policy makers and the development of strategies to support and promote agricultural management practices with benefits for soil quality.L. Barão and C. Ferreira were supported by the grants SFRH/BPD/115681/2016 and SFRH/BPD/120093/2016, respectively, from the Portuguese Fundação para a Ciência e TecnologiaiSQAPER is funded by the European Union's Horizon 2020 Programme for research & innovation under grant agreement no 635750the Chinese Ministry of Science and Technology (grant nr:2016YFE011270)the Chinese Academy of Sciences (grant nr:16146KYSB20150001)and the Swiss State Secretariat for Education, Research and Innovation. Contract: 15.0170-1

Application of soil quality indices to assess the status of agricultural soils irrigated with treated wastewaters

The supply of water is limited in some parts of the Mediterranean region, such as southeastern Spain. The use of treated wastewater for the irrigation of agricultural soils is an alternative to using better-quality water, especially in semi-arid regions. On the other hand, this practice can modify some soil properties, change their relationships and influence soil quality. In this work two soil quality indices were used to evaluate the effects of irrigation with treated wastewater in soils. The indices were developed studying different soil properties in undisturbed soils in SE Spain, and the relationships between soil parameters were established using multiple linear regressions. These indices represent the balance reached among properties in "steady state" soils. This study was carried out in four study sites from SE Spain irrigated with wastewater, including four study sites. The results showed slight changes in some soil properties as a consequence of irrigation with wastewater, the obtained levels not being dangerous for agricultural soils, and in some cases they could be considered as positive from an agronomical point of view. In one of the study sites, and as a consequence of the low quality wastewater used, a relevant increase in soil organic matter content was observed, as well as modifications in most of the soil properties. The application of soil quality indices indicated that all the soils of study sites are in a state of disequilibrium regarding the relationships between properties independent of the type of water used. However, there were no relevant differences in the soil quality indices between soils irrigated with wastewater with respect to their control sites for all except one of the sites, which corresponds to the site where low quality wastewater was used

Effects of diversionary feeding on abundance of microbes involved in soil nitrogen cycling on a Mediterranean mountain

This paper is dedicated to the memory of Dr. Lily Pereg (1965-2019), soil scientist.Soil microorganisms maintain soil functions, playing a key role in nutrient cycling. However, human activities may alter ecological processes through, for instance, wildlife management tools, which affect environment conditions. Some management tools, such as diversionary feeding, are a source of organic matter and promote high animal densities in small areas, which could affect soil properties and nutrient cycling. This study evaluated how diversionary food inputs that aim to manage an exotic wild ungulate (Ammotragus lervia) can affect the soil potential for microbial N cycling on a Mediterranean mountain in SE Spain. We quantified the functional genes involved in N cycling present in soil exposed to diversionary feeding and compared soil characteristics from three areas: feeding station soil, contour area soil (surrounding the feeding station) and a reference soil (not influenced by supplementary feeding). Our results showed that the amount of the amoA-arch gene (from ammonia-oxidising archaea), the nifH gene (associated with N-fixation), the nirK gene (associated with denitrification) and the ureC gene (associated with ureolysis) were smaller in the feeding stations than in other areas. However, the nirS and nosZ genes (associated with denitrification) were more abundant in soil from feeding stations than in the reference soil. Our results suggest that diversionary feeding modifies microbial abundance and alters nitrogen cycle dynamics because of nutrient inputs and biochemical changes in soil.We thank the Ministry of Tourism, Culture and the Environment of the Murcia Region. Pascual-Rico was supported by a pre-doctoral grant from the Spanish Ministry of Education, Culture and Sport (FPU13/05460). The study was partially supported by MINECO/MICINN and ERDF (Projects “SOMOPECAR” CGL2015-66966-C2-1-R and “TRASCAR” RTI2018-099609-B-C21).Peer reviewe

Changes in Soil Microbial Community Structure Influenced by Agricultural Management Practices in a Mediterranean Agro-Ecosystem

Agricultural practices have proven to be unsuitable in many cases, causing considerable reductions in soil quality. Land management practices can provide solutions to this problem and contribute to get a sustainable agriculture model. The main objective of this work was to assess the effect of different agricultural management practices on soil microbial community structure (evaluated as abundance of phospholipid fatty acids, PLFA). Five different treatments were selected, based on the most common practices used by farmers in the study area (eastern Spain): residual herbicides, tillage, tillage with oats and oats straw mulching; these agricultural practices were evaluated against an abandoned land after farming and an adjacent long term wild forest coverage. The results showed a substantial level of differentiation in the microbial community structure, in terms of management practices, which was highly associated with soil organic matter content. Addition of oats straw led to a microbial community structure closer to wild forest coverage soil, associated with increases in organic carbon, microbial biomass and fungal abundances. The microbial community composition of the abandoned agricultural soil was characterised by increases in both fungal abundances and the metabolic quotient (soil respiration per unit of microbial biomass), suggesting an increase in the stability of organic carbon. The ratio of bacteria:fungi was higher in wild forest coverage and land abandoned systems, as well as in the soil treated with oat straw. The most intensively managed soils showed higher abundances of bacteria and actinobacteria. Thus, the application of organic matter, such as oats straw, appears to be a sustainable management practice that enhances organic carbon, microbial biomass and activity and fungal abundances, thereby changing the microbial community structure to one more similar to those observed in soils under wild forest coverage