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The objective of this paper is to design and implement a lawnmower robot that can be used to mow grass from lawns and playgrounds remotely, online, or autonomously. The robot follows a rectangle zigzag trajectory through the lawn without any human interference. A set of concurrently running behaviors are defined to perform mowing operation. Sonar ranging is used to detect and avoid obstacles continuously throughout the route. The micro-controller connects to an ethernet board and uploads the robot's functions to a web server. Through the web server, users can monitor a 3D model of the moving rover and data from the lawnmower sensors. In addition, the robot's behaviors and connections are uploaded to IoT analytics platform to aid the performance evaluation and feature development.

The logo, as an institutional graphic representation, transmits the values and fundamental principles of the institutions. The objective of the research was to expose the factors that can motivate changes in the iconic and chromatic elements that make up logos, and the benefits that these can have for higher education institutions. The methodology used was qualitative and documentary, with 18 units of analysis from 2010 to 2022, the logos of the State University of Milagro in Ecuador were compared. Among the results, it has been observed that the correct graphic conformation of the logos can help correct weaknesses in the visual identity of the institutions that present brand association problems. It concludes, that the lack of knowledge of the structural principles of the identity manual and of the brand projection are causes of the bad perception that the public has of the values, principles, and technological scope of the institutions.

Mediterranean forests are considered to be highly vulnerable ecosystems to climate change because they are water- and nutrient-limited. However, experimental evidence of the combined effects of increasing drought and warming on biogeochemical cycles in these ecosystems is still extremely scarce. To fill this gap, we analyzed during four consecutive years the impacts of rainfall reduction (RE; ambient vs. ~30% reduction in rainfall), soil warming (W; ambient vs. ~ 1 °C increase) and their interaction on biogeochemical cycling of C, N and P in Mediterranean forests. Rainfall exclusion translated into quick significant reductions of soil organic matter (SOM), enzymatic activity (β-glucosidase, urease and acid phosphatase activities) and nutrient availability (ammonium, nitrate and phosphorus) one year after the application of the treatments. These effects were consistent over time. Warming acted synergistically with rainfall reduction to further decrease C-related variables (SOM and β-glucosidase). SOM reduction in forest soils might be the result of delayed leaf senescence as a drought tolerant trait in the forest trees. Warming also had direct positive effects on N- and P- related variables that partially counteracted the negative effects of rainfall reduction on these variables. Overall, our results showed that the different components of climate change (drought and warming) have complex direct and interactive effects on biogeochemical cycles of Mediterranean forests that differ among soil nutrients (C, N, P). Consequently, drought and warming might cause an unbalance in natural biogeochemical cycles of Mediterranean forests, with important consequences for ecosystem functioning.

El siguiente artículo tiene por finalidad comparar diversas categorías que engloban al régimen contable aplicado para el control del financiamiento y gasto en la campaña electoral, entre Chile y Colombia como p íses sudamericanos, debido a la similitud que presentan en avances de dicha materia. Ello, se efectúa a partir del marco de referencia conceptual y la experiencia comparada, a través de un enfoque narrativo y explicativo, donde se analizan el conjunto de variables comparables con la finalidad de concluir los puntos o avances con los que, Chile debería comprometerse de cara al futuro próximo. Finalmente, se apertura una propuesta de líneas de investigación, las cuales resultarían beneficiosas para continuar avanzando en desarrollar esta incipiente ciencia contable electoral.

The cloud discontinuity of Venus is a planetary-scale phenomenon known to be recurrent since, at least, the 1980s. It was initially identified in images from JAXA’s orbiter Akatsuki. This disruption is associated to dramatic changes in the clouds’ opacity and distribution of aerosols and is interpreted as a new type of Kelvin wave. The phenomenon may constitute a critical piece for our understanding of the thermal balance and atmospheric circulation of Venus. The reappearance on the dayside middle clouds four years after its last detection with Akatsuki/IR1 is reported in this work. We characterize its main properties using exclusively near-infrared images from amateur observations for the first time. The discontinuity exhibited tempοrаl variations in its zonal speed, orientation, length, and its effect over the clouds’ albedo during the 2019/2020 eastern elongation in agreement with previous rеρorts. Moreover, amateur observations are compared with simultaneous observations by Akatsuki UVI and LIR confirming that the discontinuity is not visible on the upper clouds’ albedo or thermal emission. While its zonal speeds are faster than the background winds at the middle clouds, and slower than winds at the clouds’ top, it is evidencing that this Kelvin wave might be transporting momentum up to upper clouds.

Recently, social networking sites have been used as a means of spreading an alarming narrative under the premise of freedom of speech, through enraging, provocative and harmful messages. Some of them, posted by powerful and influential people, have empowered a group of individuals who have spoken up and expressed their approval of said messages through increasingly harsher language, as well as violent actions. Some of them were racist in tone, and increasingly widespread on several social media platforms, such as Twitter, where the issue of racial inequality fuels increasing division and hatred. Dear White People is a Netflix series, based on a 2014 film of the same title, depicting Winchester University, an ethnically diverse college in the United States of America, where a conflict along racial lines erupts. At the same University, Samantha White, a junior Media Studies major, begins hosting a radio show called “Dear White People”, addressed to Caucasian students in order to make them aware of what Blackness means in a judgmental, predominantly white society. The aim of this article is to present how influential social networking is in society by using the example of Dear White People Vol. 2, as well as to illustrate how the issue of racism increases in magnitude through a narrative that spreads and encourages individuals to take verbal and physical actions against the black minority.

The Walker and Syers model predict that phosphorus (P) availability decreases with time leading to a final stage known as retrogression. We tested the validity of the Walker and Syers model in the Canary Islands, a soil chronosequence ranging from 300 years to 11 million years under recurrent episodes of atmospheric dust-containing P inputs. In particular, we compared our results with those from the volcanic soil chronosequences described in the Hawaii Islands and in Arizona, as they share key biological and/or geological characteristics. In three islands of the Canarian Archipelago, we selected 18 independent sites dominated by mature Pinus canariensis forests and grouped them into six age classes. For each site, soil samples were analyzed for known proxies of soil nitrogen (N), P and cations availability. We also analyzed the P. canariensis needles for N, P and cation contents. We found tendencies similar to those observed in other soil chronosequences: maximum N and P concentrations at intermediate ages and lower P concentrations in the older soils. The nutrient dynamics suggested that the older sites may indeed be approaching the retrogression stage but at lower rates than in other similar chronosequences. Differences from other chronosequences are likely due to the drier Canarian climate, the higher P deposition rates originating from the nearby Sahara Desert and the top soil horizon studied. Our results confirm the validity of the Walker and Syers model for the Canary Islands despite the influence that the high P deposition rates and the seasonally dry climate may have on soil development and P pools in P. canariensis ecosystems.

Ongoing global warming and alterations in rainfall patterns driven by climate change are known to have large impacts on biogeochemical cycles, particularly on drylands. In addition, the global increase in atmospheric nitrogen (N) deposition can destabilize primary productivity in terrestrial ecosystems, and phosphorus (P) may become the most limiting nutrient in many terrestrial ecosystems. However, the impacts of climate change on soil P pools in drylands remain poorly understood. Furthermore, it is unknown whether biocrusts, a major biotic component of drylands worldwide, modulate such impacts. Here we used two long-term (8-10 years) experiments conducted in Central (Aranjuez) and SE (Sorbas) Spain to test how a ~2.5°C warming, a ~30% rainfall reduction and biocrust cover affected topsoil (0-1 cm) P pools (non-occluded P, organic P, calcium bound P, occluded P and total P). Warming significantly increased most P pools-except occluded P-in Aranjuez, whereas only augmented non-occluded P in Sorbas. The rainfall reduction treatment had no effect on the soil P pools at any experimental site. Biocrusts increased most soil P pools and conferred resistance to simulated warming for major P pools at both sites, and to rainfall reduction for non-occluded and occluded P in Aranjuez. Synthesis. Our findings provide novel insights on the responses of soil P pools to warming and rainfall reduction, and highlight the importance of biocrusts as modulators of these responses in dryland ecosystems. Our results suggest that the observed negative impacts of warming on dryland biocrust communities will decrease their capacity to buffer changes in topsoil P driven by climate change., Departamento de Sistemas Físicos, Químicos y Naturales

Unlike plants and vertebrates, the ecological preferences, and potential vulnerabilities of soil invertebrates to environmental change, remain poorly understood in terrestrial ecosystems globally. We conducted a cross-biome survey including 83 locations across six continents to advance our understanding of the ecological preferences and vulnerabilities of the diversity of dominant and functionally important soil invertebrate taxa, including nematodes, arachnids and rotifers. The diversity of invertebrates was analyzed through amplicon sequencing. Vegetation and climate drove the diversity and dominant taxa of soil invertebrates. Our results suggest that declines in forest cover and plant diversity, and reductions in plant production associated with increases in aridity, can result in reductions of the diversity of soil invertebrates in a drier and more managed world. We further developed global atlases of the diversity of these important soil invertebrates, which were cross-validated using an independent database. Our study advances the current knowledge of the ecological preferences and vulnerabilities of the diversity and presence of functionally important soil invertebrates in soils from across the globe. This information is fundamental for improving and prioritizing conservation efforts of soil genetic resources and management policies.

Advances in remote sensing hardware have led to a significantly increased capability for high-quality data acquisition, which allows the collection of remotely sensed images with very high spatial, spectral, and radiometric resolution. This trend calls for the development of new techniques to enhance the way that such unprecedented volumes of data are stored, processed, and analyzed. An important approach to deal with massive volumes of information is data compression, related to how data are compressed before their storage or transmission. For instance, hyperspectral images (HSIs) are characterized by hundreds of spectral bands. In this sense, high-performance computing (HPC) and high-throughput computing (HTC) offer interesting alternatives. Particularly, distributed solutions based on cloud computing can manage and store huge amounts of data in fault-tolerant environments, by interconnecting distributed computing nodes so that no specialized hardware is needed. This strategy greatly reduces the processing costs, making the processing of high volumes of remotely sensed data a natural and even cheap solution. In this paper, we present a new cloud-based technique for spectral analysis and compression of HSIs. Specifically, we develop a cloud implementation of a popular deep neural network for non-linear data compression, known as autoencoder (AE). Apache Spark serves as the backbone of our cloud computing environment by connecting the available processing nodes using a master–slave architecture. Our newly developed approach has been tested using two widely available HSI data sets. Experimental results indicate that cloud computing architectures offer an adequate solution for managing big remotely sensed data sets.

According to EU regulations, member states shall take measures to encourage the recycling of biowaste in a way that fulfils a high level of environmental protection. In Spain, the separate collection of biowaste is only implemented in some regions. For this reason, a pilot scheme based on an information campaign and the location of a specific brown container for biowaste in specific zones of the city was carried out in Castelló de la Plana (Spain) over a period of six months. In this period, the collection and composition of the biowaste was monitored in depth with the goal of determining the evolution of the efficiency of the new collection system over time. In the zones, the quality rate in the biowaste container increased as the pilot study progressed, finally reaching 90%. The rate of biowaste separation also increased in the three zones over time, although in different ways, which means that there is greater collaboration on the part of citizens. On the other hand, an analysis of the rate of net biowaste daily collection from zones 2 and 3 has shown that their value increases as the rate of containerization of biowaste decreases. Therefore, to obtain better results it will be necessary to increase the containerization of biowaste, that is, to reduce the distance from the citizen to the container. It can thus be said that there is a positive evolution of the experience, which boosts confidence when it comes to implementing the system throughout the city.

Belowground organisms play critical roles in maintaining multiple ecosystem processes, including plant productivity, decomposition, and nutrient cycling. Despite their importance, however, we have a limited understanding of how and why belowground biodiversity (bacteria, fungi, protists, and invertebrates) may change as soils develop over centuries to millennia (pedogenesis). Moreover, it is unclear whether belowground biodiversity changes during pedogenesis are similar to the patterns observed for aboveground plant diversity. Here we evaluated the roles of resource availability, nutrient stoichiometry, and soil abiotic factors in driving belowground biodiversity across 16 soil chronosequences (from centuries to millennia) spanning a wide range of globally distributed ecosystem types. Changes in belowground biodiversity during pedogenesis followed two main patterns. In lower-productivity ecosystems (i.e., drier and colder), increases in belowground biodiversity tracked increases in plant cover. In more productive ecosystems (i.e., wetter and warmer), increased acidification during pedogenesis was associated with declines in belowground biodiversity. Changes in the diversity of bacteria, fungi, protists, and invertebrates with pedogenesis were strongly and positively correlated worldwide, highlighting that belowground biodiversity shares similar ecological drivers as soils and ecosystems develop. In general, temporal changes in aboveground plant diversity and belowground biodiversity were not correlated, challenging the common perception that belowground biodiversity should follow similar patterns to those of plant diversity during ecosystem development. Taken together, our findings provide evidence that ecological patterns in belowground biodiversity are predictable across major globally distributed ecosystem types and suggest that shifts in plant cover and soil acidification during ecosystem development are associated with changes in belowground biodiversity over centuries to millennia. European Union's Horizon 2020 research and innovation program under Marie Sklodowska-Curie Grant [702057]; US National Science FoundationNational Science Foundation (NSF) [EAR1331828, DEB 1556090] This project received funding from the European Union's Horizon 2020 research and innovation program under Marie Sklodowska-Curie Grant Agreement 702057. N.F. was supported through grants from the US National Science Foundation (EAR1331828, DEB 1556090). Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the US Government. An extended version of the acknowledgments is provided in SI Appendix. Public domain – authored by a U.S. government employee

Waste collection is one of the most important public services in a town. However, waste collection has not been effectively implemented in some places due to the lack of economic and management resources. The waste is placed in inappropriate sites with the consequent risks of pollution and unhealthy conditions for the inhabitants. Therefore, establishing a municipal solid waste collection plan can be complicated. The methodologies and techniques that work in countries with medium and high income levels cannot be extrapolated to others with low income level because the boundary conditions are widely different. The aim of this paper is to design a municipal solid waste collection system adapted to this type of situation where not much money can be invested and where data are limited. In these cases, municipalities need to use their existing resources effectively. This paper offers a methodology for these cases as well as a case study. The first step was to gather information about the type and amount of waste generated and the characteristics of the town. The second step was to propose the location of the bins and, finally, the waste collection routes. With all these data, the technical and human resources were set. The methodology used was validated in a real case, the town of Nikki (Benin) in Africa. The collection of three waste fractions was designed with the actual resources of the city in order to offer a realistic implementation. Similar situations can be found around the world, and this case study can be used as an example to improve the waste management practices in some places with low resources.

Soil biogeochemical functioning in Mediterranean pine forests is characterized by the typical alternation between wet and mild (or cold) winters and dry and warm (or hot) summers in the Mediterranean climate, which restrict soil microbial activity to short periods and determine the unique properties of nutrient cycling in these ecosystems. Besides, soil dry-rewetting cycles are frequent in all seasons with a strong influence on soil microbial population and biogeochemical processes. Mediterranean regions are also affected by ongoing global climate change with decreasing precipitation, increasing temperature, increasing atmospheric water demand, and higher climatic variability that will exacerbate soil drying-wetting cycles. Finally, Mediterranean pine ecosystems are periodically exposed to intense and recurrent fires and other disturbances, such as insect pests and parasites, which affect the input and output of nutrients and their short- and long-term availability. I review here soil functioning in Mediterranean pine forests by looking at key indicators of carbon and nutrient cycling, such as microbial biomass, soil respiration, enzyme activity, and nutrient availability. Dry-rewetting cycles and forest disturbances affect in different degrees to C and nutrient cycling in pine forests, which may determine higher microbial activity and nutrient limitation than expected.

Background:According to EU regulations, member states shall take measures to encourage the recycling of biowaste in a way that fulfils a high level of environmental protection. In Spain, the separate collection of biowaste is only implemented in some regions. For this reason, a pilot scheme based on an information campaign and the location of a specific brown container for biowaste in specific zones of the city was carried out in Castellón de la Plana (Spain) over a period of six months. In this period, the collection and composition of the biowaste was monitored in depth with the goal of determining the evolution of the efficiency of the new collection system over time. Results:In the zones, the quality rate in the biowaste container increased as the pilot study progressed, finally reaching 90%. The rate of biowaste separation also increased in the three zones over time, although in different ways, which means that there is greater collaboration on the part of citizens. On the other hand, an analysis of the rate of net biowaste daily collection from zones 2 and 3 has shown that their value increases as the rate of containerization of biowaste decreases. Conclusions:In order to obtain better results in the biowaste quality rate it will be necessary to increase the containerization of biowaste, that is, to reduce the distance from the citizen to the container. It can thus be said that there is a positive evolution of the experience, which boosts confidence when it comes to implementing the system throughout the city.

Soil carbon losses to the atmosphere, via soil heterotrophic respiration, are expected to increase in response to global warming, resulting in a positive carbon-climate feedback. Despite the well-known suite of abiotic and biotic factors controlling soil respiration, much less is known about how the magnitude of soil respiration responses to temperature changes over soil development and across contrasting soil properties. Here we investigated the role of soil development stage and soil properties in driving the responses of soil heterotrophic respiration to temperature. We incubated soils from eight chronosequences ranging in soil age from hundreds to million years, and encompassing a wide range of vegetation types, climatic conditions and chronosequences origins, at three assay temperatures (5 °C, 15 °C and 25 °C). We found a consistent positive effect of assay temperature on soil respiration rates across the eight chronosequences evaluated. However, chronosequences parent materials (sedimentary/sand dunes or volcanic) and soil properties (pH, phosphorus content and microbial biomass) determined the magnitude of this temperature effect. Finally, we observed a positive effect of soil development stage on soil respiration across chronosequences that did not alter the magnitude of assay temperature effects. Our work reveals that key soil properties alter the magnitude of the positive effect of temperature on soil respiration found across ecosystem types and soil development stages. This information is essential to better understand the magnitude of the carbon-climate feedback and thus to establish accurate greenhouse gas emission targets. This research received funding from the European Union’s Horizon 2020 research and innovation program under Marie Sklodowska-Curie Grant Agreement 702057. M.D. was supported by an FPU fellowship from the Spanish Ministry of Education, Culture and Sports (FPU-15/00392). M.D. and F.T.M. are supported by the European Research Council (Consolidator Grant Agreement No 647038, BIODESERT). M.D-B. is supported by a Large Research Grant from the British Ecological Society (grant agreement n° LRA17\1193, MUSGONET). F.T.M and M.D-B. acknowledge support from the Spanish Ministry (project CGL2017-88124-R). PGP and M.D-B. are supported by a Ramón y Cajal grant from the Spanish Ministry of Science and Innovation (RYC2018-024766-I and RYC2018-025483-I, respectively). F.T.M. acknowledges support from the Generalitat Valenciana (CIDEGENT/2018/041).

16 páginas.- 3 figuras.-Supporting information are accessible at h ttps://doi.org/10.17632/y8k3fddnz2.1, An increase in tree mortality rates as a consequence of biotic disturbances has been detected worldwide. Biotic disturbances in forests might cause significant impacts at ecosystem-level, with strong effects on soil biological activity and organic matter transformation. However, very few empirical studies have explored to date the consequences of biotic disturbances for soil microbial communities and C and N cycles. Here, we assessed the effects of Quercus suber dieback, caused by the exotic root pathogen Phytophthora cinnamomi, on the soil microbial community and key components of the C and N cycle. We used a spatially explicit neighborhood approach to analyze the effects of Q. suber trees with different health status and non-declining coexistent species on soil variables. The study was replicated in the two main Q. suber forest types of the region (closed forests and open woodlands) with contrasting soil texture characteristics. Pathogen-induced tree dieback did not affect microbial functional diversity or biomass, but translated into lower soil microbial respiration. Tree mortality induced changes in several variables of the C and N cycle, but the sign and magnitude of these effects varied depending on the local characteristics of soil texture. Coexistent species differed strongly from Q. suber in their effects on the C and N cycle. Overall, our results show that tree dieback due to invasive pathogens translates into complex short- and long-term effects on different components of the C and N cycles, despite no effects on microbial functional diversity and biomass., This research was supported by the Ministerio de Ciencia e Innovación (MICINN) projects CGL2010-21381 and CGL2011-26877 (RETROBOS). J.M.A. was supported by a FPU-MEC grant (AP2010-0229) and B.I. FPI-MICINN grant (BES-2009-017111).

Little is known about the role of biocrusts in regulating the responses of N2O and CH4 fluxes to climate change in drylands. Here, we aim to help filling this knowledge gap by using an 8-year field experiment in central Spain where temperature and rainfall are being manipulated (~ 1.9°C warming, 33% rainfall reduction and their combination) in areas with and without well-developed biocrust communities. Areas with initial high cover of well-developed biocrusts showed lower N2O emissions, enhanced CH4 uptake and higher abundances of functional genes linked to N2O and CH4 fluxes compared with areas with poorly developed biocrusts. Moreover, biocrusts modulated the responses of gases emissions and related functional genes to warming and rainfall reductions. Specifically, we found under rainfall exclusion and its combination with warming a sharp reduction in N2O fluxes (~ 96% and ~ 197%, respectively) only under well-developed biocrust cover. Warming and its combination with rainfall exclusion reduced CH4 consumption in areas with initial low cover of well-developed biocrust, whereas rainfall exclusion enhanced CH4 uptake only in areas with high initial cover of well-developed biocrusts. Similarly, the combination of warming and rainfall exclusion increased the abundance of the nosZ gene compared to the rainfall exclusion treatment and increased the abundance of the pmoA gene compared to the control, but only in areas with low biocrust cover. Taken together, our results indicate that well-developed biocrust communities could counteract the impact of warming and altered rainfall patterns on soil N2O and CH4 fluxes, highlighting their importance and the need to preserve them to minimize climate change impacts on drylands. A. L. is supported by a FPI fellowship from the Spanish Ministry of Economy and Competitiveness (BES-2014-067831). M.D-B. acknowledges support from the Marie Sklodowska-Curie Actions of the Horizon 2020 Framework Programme H2020-MSCA-IF-2016 under REA Grant Agreement No. 702057 (CLIMIFUN) and the BES Grant Agreement No. LRA17\1193 (MUSGONET). J.D acknowledges support from the Fundação para Ciência e Tecnologia (IF/00950/2014) and the FEDER, within the PT2020 Partnership Agreement and COMPETE 2020 (UID/BIA/04004/2013). This research was supported by the European Research Council (ERC Grant Agreements 242658 [BIOCOM] and 647038 [BIODESERT]), by the Spanish Ministry of Economy and Competitiveness (BIOMOD project, ref. CGL2013-44661-R and AGL2015-64582-C3-3-R project) and by the Comunidad de Madrid and European Structural and Investment Funds (AGRISOST-CM S2013/ABI-2717). F.T.M. acknowledges support from Generalitat Valenciana (BIOMORES project, ref. CIDEGENT/2018/041). B.K.S research on the topic of biodiversity and ecosystem functions is funded by Australian Research Council (DP170104634).

The role of soil biodiversity in regulating multiple ecosystem functions is poorly understood, limiting our ability to predict how soil biodiversity loss might affect human wellbeing and ecosystem sustainability. Here, combining a global observational study with an experimental microcosm study, we provide evidence that soil biodiversity (bacteria, fungi, protists and invertebrates) is significantly and positively associated with multiple ecosystem functions. These functions include nutrient cycling, decomposition, plant production, and reduced potential for pathogenicity and belowground biological warfare. Our findings also reveal the context dependency of such relationships and the importance of the connectedness, biodiversity and nature of the globally distributed dominant phylotypes within the soil network in maintaining multiple functions. Moreover, our results suggest that the positive association between plant diversity and multifunctionality across biomes is indirectly driven by soil biodiversity. Together, our results provide insights into the importance of soil biodiversity for maintaining soil functionality locally and across biomes, as well as providing strong support for the inclusion of soil biodiversity in conservation and management programmes. Combining field data from 83 sites on five continents, together with microcosm experiments, the authors show that nutrient cycling, decomposition, plant production and other ecosystem functions are positively associated with a higher diversity of a wide range of soil organisms. Marie Sklodowska-Curie We thank N. Fierer, M. Gebert, J. Henley, V. Ochoa, F. T. Maestre and B. Gozalo for their help with laboratory analyses; O. Sala, C. Siebe, C. Currier, M. A. Bowker, V. Parry, H. Lambers, P. Vitousek, V. M. Pena-Ramirez, L. Riedel, J. Larson, K. Waechter, W. Williams, S. Williams, B. Sulman, D. Buckner and B. Anacker for their help with soil sampling in Colorado, Hawaii, Iceland, New Mexico, Arizona, Mexico and Australia; the City of Boulder Open Space and Mountain Parks for allowing us to conduct these samplings; C. Cano-Diaz for her advice about R analyses; S. K. Travers for her help with mapping. This project has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement no. 702057. M.D.-B. is supported by the Spanish Government under a Ramon y Cajal contract RYC2018-025483-I. This research is supported by the Australian Research Council projects (DP170104634; DP190103714). S.A. and F.D.A. are funded by FONDECYT 1170995, IAI-CRN 3005, PFB-23 (from CONICYT) and P05-002 (from Millennium Scientific Initiative). N.A.C. acknowledges support from Churchill College, University of Cambridge; and M.A.W. from the Wilderness State Park, Michigan for access to sample soil and conduct ecosystem survey. B.K.S. acknowledges a research award from the Humboldt Foundation. J.-Z.H. acknowledges support from the Australia Research Council (project DP170103628); and A.G. from the Spanish Ministry (project CGL2017-88124-R). F.B. thanks the Spanish Ministry and FEDER funds for the CICYT project AGL2017-85755-R, the CSIC project 201740I008 and funds from 'Fundacion Seneca' from Murcia Province (19896/GERM/15). P.T. thanks K. Little for her help with laboratory analyses. S.C.R. was supported by the US Geological Survey Ecosystems Mission Area. Any use of trade, firm or product names is for descriptive purposes only and does not imply endorsement by the US Government. S.N. was funded by the Austrian Science Fund (grant Y801-B16). Public domain – authored by a U.S. government employee

This paper describes the laboratory-scale simulation of the behaviour of rejects from a biological-mechanical treatment (BMT) plant in Castell&oacute, n (Spain). For this purpose, four lysimeters were built, with different densities. Simulations were carried out for 7 weeks and leachate recirculation was applied to two of them. The experimental results allowed us to determine: (i) dirt in fractions, which was relatively high (up to 15% in some fractions) due to biological processes, (ii) the field capacity for this waste with similar values to other works, which varied depending on the experiment, (iii) variation in the biomass percentage which lowered after experiments in all cases (59.5% lower on average), and the rejects&rsquo, calorific value was higher after experiments (28.2% on average), (iv) the evolution of leachate properties with or without recirculation, where percolation, in addition to the dragging of soluble materials, stabilised waste, which diminished its biological activity. Rejects&rsquo, increased calorific value will allow combustible material to be recovered in the future as a way to exploit the energy potential stored in landfills.

1. The importance of soil phosphorus (P) is likely to increase in coming decades due to the growing atmospheric nitrogen (N) deposition originated by industrial and agricultural activities. We currently lack a proper understanding of the main drivers of soil P pools in coastal dunes, which rank among the most valued priority conservation areas worldwide. 2. Here, we evaluated the joint effects of biotic (i.e. microbial abundance and richness, vegetation and cryptogams cover) and abiotic (i.e. pH and aridity) factors on labile, medium‐lability and recalcitrant soil P pools across a wide aridity gradient in the Atlantic coast of the Iberian Peninsula. 3. Climate determined the availability of medium‐lability, recalcitrant and total P, but had a minor net effect on labile P, which was positively and significantly related to the presence of plants, mosses and lichens. Medium‐lability P was significantly influenced by soil bacterial richness and abundance (positively and negatively, respectively). 4. Our results suggest that micro‐organisms transfer P from medium‐lability pool to more labile one. At the same time, increases in bacterial richness associated to biofilms might be involved in the thickening of the medium‐lability P pool in our climosequence. 5. These bacterial‐mediated transfers would confer resistance to the labile P pool under future climate change and uncover an important role of soil micro‐organisms as modulators of the geochemical P cycle. This project was financed by FEDER/Ministerio de Ciencia, Innovación y Universidades-Agencia Estatal de Investigación/Proyect (CGL2017-88124-R), European Research Council (ERC Grant Agreement 647038 [BIODESERT]) and the Fundaçã o para Ciência e Tecnologia (IF/00950/2014) and the FEDER, within the PT2020 Partnership Agreement and COMPETE 2020 (UID/BIA/04004/2013). F.T.M. acknowledges support from Generalitat Valenciana (CIDEGENT/2018/041). B.K.S. acknowledge research support on microbes and ecosystem functions from the Australian Research Council (DP170104634) and Research Award from the Humboldt Foundation.

The importance of soil age as an ecosystem driver across biomes remains largely unresolved. By combining a cross-biome global field survey, including data for 32 soil, plant, and microbial properties in 16 soil chronosequences, with a global meta-analysis, we show that soil age is a significant ecosystem driver, but only accounts for a relatively small proportion of the cross-biome variation in multiple ecosystem properties. Parent material, climate, vegetation and topography predict, collectively, 24 times more variation in ecosystem properties than soil age alone. Soil age is an important local-scale ecosystem driver; however, environmental context, rather than soil age, determines the rates and trajectories of ecosystem development in structure and function across biomes. Our work provides insights into the natural history of terrestrial ecosystems. We propose that, regardless of soil age, changes in the environmental context, such as those associated with global climatic and land-use changes, will have important long-term impacts on the structure and function of terrestrial ecosystems across biomes., This project received funding from the European Union’s Horizon 2020 research and innovation program under the Marie Sklodowska-Curie Grant Agreement No. 702057 (CLIMIFUN). M.D.-B. is supported by a Ramón y Cajal grant from the Spanish Ministry of Science and Innovation (RYC2018-025483-I), and by the BES Grant Agreement No. LRB17\1019 (MUSGONET). F.B. is grateful to the Spanish Ministry and FEDER funds for the project AGL2017–85755-R, the i-LINK+2018 (LINKA20069) from CSIC, and received funds from “Fundación Séneca” from Murcia Province (19896/GERM/15). S.R. was supported by the US Geological Survey Ecosystems Mission Area. C.P. acknowledges support from the Spanish State Plan for Scientific and Technical Research and Innovation (2013–2016), award ref. AGL201675762-R (AEI/FEDER, UE). A.G. acknowledges support from the Spanish Ministry of Science (CGL2017-88124-R). F.A. is supported by FONDECYT 11180538 and S.A. by FONDECYT 1170995. We would like to thank Peter Vitousek for his comments on a previous draft of this paper. Moreover, we thank Matt Gebert, Jessica Henley, Fernando T. Maestre, Victoria Ochoa, and Beatriz Gozalo for their help with lab analyses, and Emilio Guirado for his advice with topographic analyses. We also want to thank Osvaldo Sala, Matthew A. Bowker, Peter Vitousek, Courtney Currier, Martin Kirchmair, Victor M. Peña-Ramírez, Lynn Riedel, Julie Larson, Katy Waechter, David Buckner, and Brian Anacker for their help with soil sampling, and to the City of Boulder Open Space and Mountain Parks for allowing us to conduct these samplings. We are also grateful to the Division of Forestry and Wildlife of the State of Hawai’i and Koke’e State Park for their logistical assistance and for allowing us access to the HA sites. The Arizona research sites were established with the support of an EPA‐STAR Graduate Fellowship (U‐916251), a Merriam‐Powell Center for Environmental Research Graduate Fellowship, an Achievement Rewards for College Scientists (ARCS) Foundation of Arizona Scholarship, and McIntire‐Stennis appropriations to Northern Arizona University and the State of Arizona. Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government.

Soil nitrogen (N) availability is a key driver of soil-atmosphere greenhouse gas (GHG) exchange, yet we are far from understanding how increases in N deposition due to human activities will influence the net soil-atmosphere fluxes of the three most important GHGs: nitrous oxide (N2O), methane (CH4) and carbon dioxide (CO2). We simulated four levels of N deposition (10, 20 and 50 kg N ha−1 yr−1, plus unfertilised control) to evaluate their effects on N2O, CH4 and CO2 soil fluxes in a semiarid shrubland in central Spain. After 8 years of experimental fertilisation, increasing N availability led to a consistent increase in N2O emissions, likely due to simultaneous increases in soil microbial nitrification and/or denitrification processes. However, only intermediate levels of N fertilisation reduced CH4 uptake, while increasing N fertilisation had no effects on CO2 fluxes, suggesting complex interactions between N deposition loads and GHG fluxes. Our study provides novel insight into the responses of GHGs to N deposition in drylands, forecasting increases in N2O emissions, and decreases in CH4 uptake rates, with likely consequences to the on-going climate change.