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Abstract We introduce NPKGRIDS, a new geospatial dataset, providing for the first time data on application rates for all three main plant nutrients, nitrogen (N), phosphorus (P, in terms of phosphorus pentoxide, P2O5) and potassium (K, in terms of potassium oxide, K2O) across 173 crops as of 2020, with a geospatial resolution of 0.05° (approximately 5.6 km at the equator). Development of NPKGRIDS adopted a data fusion approach to integrate crop mask information with eight published datasets of fertilizer application rates, compiled from either georeferenced data or national and subnational statistics. Furthermore, the total applied mass of N, P2O5, and K2O were benchmarked against the country level information from FAO and the International Fertilizers Association (IFA) and validated against data available from National Statistical Offices (NSOs). NPKGRIDS can be used in global modelling, and decision and policy making to help maximize crop yields while reducing environmental impacts.

Abstract Many countries have implemented policies to reduce the use of chemical inputs in agriculture. However, these policies face many obstacles that limit their effectiveness. The purpose of this paper is to review the main challenges associated with reducing chemical inputs in agriculture and to propose potential solutions. Our analysis, based on a literature review linking agronomy and economics, shows that several agronomic options have proven effective in reducing chemical inputs or mitigating their negative impacts. We argue that the organization of the agri-food system itself is a major barrier to their implementation. Involving all stakeholders, from the chemical input industry to consumers, and designing appropriate policy frameworks are key to address this issue. We recommend combining different policy instruments, such as standards, taxes and subsidies, in a simplified and coherent way to increase effectiveness and ensure better coordination in the adoption of sustainable practices.

Abstract Land degradation is a complex socio-environmental threat, which generally occurs as multiple concurrent pathways that remain largely unexplored in Europe. Here we present an unprecedented analysis of land multi-degradation in 40 continental countries, using twelve dataset-based processes that were modelled as land degradation convergence and combination pathways in Europe’s agricultural (and arable) environments. Using a Land Multi-degradation Index, we find that up to 27%, 35% and 22% of continental agricultural (~2 million km2) and arable (~1.1 million km2) lands are currently threatened by one, two, and three drivers of degradation, while 10–11% of pan-European agricultural/arable landscapes are cumulatively affected by four and at least five concurrent processes. We also explore the complex pattern of spatially interacting processes, emphasizing the major combinations of land degradation pathways across continental and national boundaries. Our results will enable policymakers to develop knowledge-based strategies for land degradation mitigation and other critical European sustainable development goals.

Abstract CROPGRIDS is a comprehensive global geo-referenced dataset providing area information for 173 crops for the year 2020, at a resolution of 0.05° (about 5.6 km at the equator). It represents a major update of the Monfreda et al. (2008) dataset (hereafter MRF), the most widely used geospatial dataset previously available, covering 175 crops with reference year 2000 at 10 km spatial resolution. CROPGRIDS builds on information originally provided in MRF and expands it using 27 selected published gridded datasets, subnational data of 52 countries obtained from National Statistical Offices, and the 2020 national-level statistics from FAOSTAT, providing more recent harvested and crop (physical) areas for 173 crops at regional, national, and global levels. The CROPGRIDS data advance the current state of knowledge on the spatial distribution of crops, providing useful inputs for modelling studies and sustainability analyses relevant to national and international processes.

China, Germany and UK were the largest net importers of pesticide hazard loads embodied in commodities in 2015, while the USA, Brazil and Spain were the largest net exporters, according to a top-down multi-region input-output analysis of footprints for 82 countries and territories.

Measurement(s) volumetric water content • water table depth Technology Type(s) computational modeling technique Factor Type(s) hydrometeorology • soil properties • land use Sample Characteristic - Environment soil Machine-accessible metadata file describing the reported data: https://doi.org/10.6084/m9.figshare.15982578

Pesticides are potent chemical agents for protecting crops and agricultural production but can have secondary adverse effects on soil biodiversity that can propagate through all dimensions of soil security. Earthworms are among the most important actors in making soil healthy because they facilitate nutrient turnover, improve aeration, facilitate water infiltration into the root zone, and control soil-borne diseases. However, earthworms have been shown to be affected by the presence of pesticide residue, with a median survival to some highly toxic active substances concentrations as small as 4 mg/kg-soil. Here we have used the estimated pesticide residue of 87 active ingredients in nine different cropping systems globally, and we have developed the corresponding dose-response curve of earthworms to estimate the percent earthworm population decline and its global distribution caused by residues in the top soil. We found that vegetable and fruits, and orchards and grapes cropping systems are leading to the greatest percent decline in earthworms population in some areas of South America, and East and South East Asia. The decline in soybean, rice, and orchards and grape in boreal regions were the greatest. The maximum decline across the cropping systems ranged between 10 and 20% in about 1.2% of the agricultural locations under consideration, but it was less than 1% in about 66% of agricultural locations. These findings call for further scrutiny of the contamination by pesticide residue in soil and long-term consequences on soil security.

Degraded plastic debris has been found in nearly all waters within and nearby urban developments as well as in the open oceans. Natural removal of suspended microplastics (MPs) by deposition is often limited by their excess buoyancy relative to water, but this can change with the attachment of biological matter. The extent to which the attached biological ballast affects MP dynamics is still not well characterised. Here, we experimentally demonstrate using a novel OMCEC (Optical Measurement of CEll colonisation) system that the biological fraction of MP aggregates has substantial control over their size, shape and, most importantly, their settling velocity. Polyurethane MP aggregates made of 80% biological ballast had an average size almost twice of those containing 5% biological ballast, and sank about two times slower. Based on our experiments, we introduce a settling velocity equation that accounts for different biological content as well as the irregular fractal structure of MP aggregates. This equation can capture the settling velocity of both virgin MPs and microbial-associated MP aggregates in our experiment with 7% error and can be used as a preliminary tool to estimate the vertical transport of MP aggregates made of different polymers and types of microbial ballast.

Abstract The detection of microbial colonization in geophysical systems is becoming of interest in various disciplines of Earth and planetary sciences, including microbial ecology, biogeochemistry, geomicrobiology, and astrobiology. Microorganisms are often observed to colonize mineral surfaces, modify the reactivity of minerals either through the attachment of their own biomass or the glueing of mineral particles with their mucilaginous metabolites, and alter both the physical and chemical components of a geophysical system. Here, we hypothesise that microorganisms engineer their habitat, causing a substantial change to the information content embedded in geophysical measures (e.g., particle size and space-filling capacity). After proving this hypothesis, we introduce and test a systematic method that exploits this change in information content to detect microbial colonization in geophysical systems. Effectiveness and robustness of this method are tested using a mineral sediment suspension as a model geophysical system; tests are carried out against 105 experiments conducted with different suspension types (i.e., pure mineral and microbially-colonized) subject to different abiotic conditions, including various nutrient and mineral concentrations, and different background entropy production rates. Results reveal that this method can systematically detect microbial colonization with less than 10% error in geophysical systems with low-entropy background production rate.

Laboratory experiments and numerical modeling were conducted to assess the effects of glycerol concentration gradients on water flow through an unsaturated loamy sand (Yellow bush sand, Australia) at 46% glycerol mass fraction and 12.5% volumetric water content. When the contaminated and uncontaminated experimental soil sections were placed into contact, two opposite mechanisms were found to drive the flow: (i) the matric potential gradient affected by concentration-dependent surface tension, viscosity, and density repelled contaminated water; and (ii) the osmotic potential gradient had an opposite effect. Experiments demonstrated that the tested sand did not exhibit the complete semipermeable characteristic necessary to induce pure osmotic flow. Rather, physicochemical effects caused by dissolved glycerol were more relevant for water flow than those induced by the osmotic potential. We confirmed our experimental finding by numerical modeling that explicitly accounted for these effects compared with our experiments and earlier experiments conducted with 7% butanol–water mixtures as benchmarks. Our results were finally confirmed by a thermodynamic interpretation of matric and osmotic potentials. Experiments suggest that a rapid transient condition occurred on the first day and that equilibrium was recovered only after >60 d. The results support the hypothesis that chemically induced water flow in the vadose zone is contributed mainly by matric and only secondarily by osmotic effects, which have displaced 3 to 10% water during the initial transient condition. Predictive tools of contaminant hydrology in unsaturated soil may have to account for the osmotic effects in particular applications that involve soil with high osmotic efficiency.

In modern agriculture, pesticides are used in combinations to protect crops. The co-existence of multiple pesticides in soil can threaten the soil biodiversity that maintains ecosystem services, hence further posing a long-term risk on food security. Here, we introduce an assessment of global soil contamination by the residue of pesticide mixtures in nine cropping systems using a fully mechanistic, spatially explicit, and time-resolved model at 0.5° × 0.5° spatial resolution (approximately 55 × 55 km at the equator) fed with georeferenced agricultural quantities, soil properties, and hydroclimatic variables. We found that 8.3 million km ^2 of treated land have more than one detectable pesticide, with pendimethalin, glyphosate, paraquat, chlorpyrifos, and chlorothalonil being the five most frequently detected. The highest pesticide mixture content was found in the ‘orchards and grapes’ cropping system (95th percentile at 7.3 mg kg soil ^−1 ). Globally, the pesticide mixture in the topsoil of approximately 1.88 million km ^2 exceeded 1 mg kg soil ^−1 for more than 180 d in a year. We estimate that 0.2 million tonnes of pesticides leach below the root zone each year globally, with glyphosate contributing the greatest fraction. The major hotspots of soil pesticide contamination are located in South America and Asia, mainly in Brazil, Argentina, Chile, China, Malaysia, and Japan. Our study shows that the accumulation of pesticide mixtures in soil is a global environmental issue that has to be explicitly accounted for in the sustainability assessment of agricultural production. We propose the use of mechanistic modelling as a tool to aid in designing pesticide management strategies and minimise residue contamination.

Australian ecosystems, particularly wetlands, are facing new and extreme threats due to climate change, land use, and other human interventions. However, more fundamental knowledge is required to understand how nutrient turnover in wetlands is affected. In this study, we deployed a mechanistic biogeochemical model of carbon (C), nitrogen (N), and sulfur (S) cycles at 0.25∘× 0.25∘ spatial resolution across wetlands in Australia. Our modeling was used to assess nutrient inputs to soil, elemental nutrient fluxes across the soil organic and mineral pools, and greenhouse gas (GHG) emissions in different climatic areas. In the decade 2008–2017, we estimated an average annual emission of 5.12 Tg-CH4, 90.89 Tg-CO2, and 2.34 × 10−2 Tg-N2O. Temperate wetlands in Australia have three times more N2O emissions than tropical wetlands as a result of fertilization, despite similar total area extension. Tasmania wetlands have the highest areal GHG emission rates. C fluxes in soil depend strongly on hydroclimatic factors; they are mainly controlled by anaerobic respiration in temperate and tropical regions and by aerobic respiration in arid regions. In contrast, N and S fluxes are mostly governed by plant uptake regardless of the region and season. The new knowledge from this study may help design conservation and adaptation plans to climate change and better protect the Australian wetland ecosystem.

Pericentric inversion of chromosome 4 can give rise to recombinant chromosomes by duplication or deletion of 4p. We report on a familial case of Wolf-Hirschhorn Syndrome characterized by GTG-banding karyotypes, FISH, and array CGH analysis, caused by a recombinant chromosome 4 with terminal 4p16.3 deletion and terminal 4q35.2 duplication. This is an aneusomy due to a recombination which occurred during the meiosis of heterozygote carrier of cryptic pericentric inversion. We also describe the adulthood and prenatal phenotypes associated with the recombinant chromosome 4.