Background and aims Organic inputs have a positive effect on the soil organic matter balance. They are therefore an important asset for soil fertility and crop growth. This study quantifies the ...additional yield effect due to organic inputs for arable crops in Europe when macronutrients are not a limiting factor. Methods A meta-analysis was performed using data from 20 long-term experiments in Europe. Maxima of yield response curves to nitrogen were compared, with and without organic inputs, under abundant P and K supply. Results We were surprised to find that, across all experiments, the mean additional yield effect of organic inputs was not significant (+ 1.4 % ± 1.6 (95 % confidence interval)). In specific cases however, especially for root and tuber crops, spring sown cereals, or for very sandy soils or wet climates, organic inputs did increase attainable yields. A significant correlation was found between increase in attainable yields and increase in soil organic matter content. Conclusions Aggregating data from 20 long-term experiments in Europe, this study shows that organic inputs and/or soil organic matter do not necessarily increase yields, given sufficient nutrients are supplied by mineral fertilisers. Results show the relevance of some environmental factors for additional yield effect of organic inputs, but no simple relation between organic inputs and crop growth.
Implementation of the Nitrates Directive (NiD) and its environmental impacts were compared for member states in the northwest of the European Union (Ireland, United Kingdom, Denmark, the Netherlands, ...Belgium, Northern France and Germany). The main sources of data were national reports for the third reporting period for the NiD (2004–2007) and results of the MITERRA-EUROPE model. Implementation of the NiD in the considered member states is fairly comparable regarding restrictions for where and when to apply fertilizer and manure, but very different regarding application limits for N fertilization. Issues of concern and improvement of the implementation of the NiD are accounting for the fertilizer value of nitrogen in manure, and relating application limits for total nitrogen (N) to potential crop yield and N removal. The most significant environmental effect of the implementation of the NiD since 1995 is a major contribution to the decrease of the soil N balance (N surplus), particularly in Belgium, Denmark, Ireland, the Netherlands and the United Kingdom. This decrease is accompanied by a modest decrease of nitrate concentrations since 2000 in fresh surface waters in most countries. This decrease is less prominent for groundwater in view of delayed response of nitrate in deep aquifers. In spite of improved fertilization practices, the southeast of the Netherlands, the Flemish Region and Brittany remain to be regions of major concern in view of a combination of a high nitrogen surplus, high leaching fractions to groundwater and tenacious exceedance of the water quality standards. On average the gross N balance in 2008 for the seven member states in EUROSTAT and in national reports was about 20 kg N ha−1 yr−1 lower than by MITERRA. The major cause is higher estimates of N removal in national reports which can amount to more than 50 kg N ha−1 yr−1. Differences between procedures in member states to assess nitrogen balances and water quality and a lack of cross-boundary policy evaluations are handicaps when benchmarking the effectiveness of the NiD. This provides a challenge for the European Commission and its member states, as the NiD remains an important piece of legislation for protecting drinking water quality in regions with many private or small public production facilities and controlling aquatic eutrophication from agricultural sources.
Hypertension is reported to be the most prevalent risk factor for cardiovascular disease in elite athletes. We aimed to review blood pressure (BP) and prevalence of hypertension in different elite ...athletes, and study whether there was an association between high BP and left ventricular hypertrophy (LVH).
A systematic review of studies reporting BP in athletes using search strategies developed for PubMed and EMBASE, including only studies with ≥100 participants. We collected data on BP, prevalence of hypertension, LVH and methods of BP measurement.
Of 3723 records identified, 51 met the inclusion criteria. These included men and women (n=138,390), aged mostly between 18 and 40 years, from varied sports disciplines. Mean systolic BP varied from 109±11 to 138±7 mm Hg and mean diastolic BP from 57±12 to 92±10 mm Hg. Strength-trained athletes had higher BP than endurance-trained athletes (131.3±5.3/77.3±1.4 vs 118.6±2.8/71.8±1.2 mm Hg, p<0.05), and there was a trend towards a higher BP in athletes training ≥10 h compared with others (121.8±3.8/73.8±2.5 vs 117.6±3.3/66.8±6.9, p=0.058), but overall there was no significant difference in BP between athletes and controls. The prevalence of hypertension varied from 0% to 83%. Some studies showed an association between high BP and LVH. Measurement methods were poorly standardised.
BP and prevalence of hypertension in athletes varied considerably partly because of variations in methodology, but type and intensity of training may contribute towards higher BP. High BP may be associated with LVH.
The Meteorological Synthesizing Centre-West (MSC-W) of the European Monitoring and Evaluation Programme (EMEP) has been performing model calculations in support of the Convention on Long Range ...Transboundary Air Pollution (CLRTAP) for more than 30 years. The EMEP MSC-W chemical transport model is still one of the key tools within European air pollution policy assessments. Traditionally, the model has covered all of Europe with a resolution of about 50 km × 50 km, and extending vertically from ground level to the tropopause (100 hPa). The model has changed extensively over the last ten years, however, with flexible processing of chemical schemes, meteorological inputs, and with nesting capability: the code is now applied on scales ranging from local (ca. 5 km grid size) to global (with 1 degree resolution). The model is used to simulate photo-oxidants and both inorganic and organic aerosols. In 2008 the EMEP model was released for the first time as public domain code, along with all required input data for model runs for one year. The second release of the EMEP MSC-W model became available in mid 2011, and a new release is targeted for summer 2012. This publication is intended to document this third release of the EMEP MSC-W model. The model formulations are given, along with details of input data-sets which are used, and a brief background on some of the choices made in the formulation is presented. The model code itself is available at www.emep.int, along with the data required to run for a full year over Europe.
Nitrogen (N) supply from organic amendments such as farmyard manure (FYM), slurries or crop residues to crops is commonly expressed in the amendment’s Nitrogen Fertiliser Replacement Value (
NFRV
). ...Values for
NFRV
can be determined by comparison of crop yield or N uptake in amended plots against mineral fertiliser-only plots.
NFRV
is then defined as the amount of mineral fertiliser N saved when using organic amendment-N (kg/kg), while attaining the same crop yield. Factors known to affect NFRV are crop type cultivated, soil type, manuring history and method or time of application. We investigated whether long-term
NFRV
depends on N application rates. Using data from eight long term experiments in Europe, values of
NFRV
at low total N supply were compared with values of
NFRV
at high total N supply. Our findings show that FYM has a significant higher
NFRV
value at high total N supply than at low total N supply (1.12 vs. 0.53,
p
= 0.04). For the other amendment types investigated,
NFRV
was also higher at high total N supply than at low total N supply, but sample sizes were too small or variations too large to detect significant differences. Farmers in Europe usually operate at high rates of total N applied. If fertiliser supplements are based on
NFRV
of the manure estimated at low total N supply, N fertiliser requirements might be overestimated. This might lead to overuse of N, lower N use efficiency and larger losses of N to the environment.
Nutrient limitation is a major constraint in crop production in sub-Saharan Africa (SSA). Here, we propose a generic and simple equilibrium model to estimate minimum input requirements of nitrogen, ...phosphorus and potassium for target yields in cereal crops under highly efficient management. The model was combined with Global Yield Gap Atlas data to explore minimum input requirements for self-sufficiency in 2050 for maize in nine countries in SSA. We estimate that yields have to increase from the current ca. 20% of water-limited yield potential to approximately 50–75% of the potential depending on the scenario investigated. Minimum nutrient input requirements must rise disproportionately more, with N input increasing 9-fold or 15-fold, because current production largely relies on soil nutrient mining, which cannot be sustained into the future.
•A new method to assess minimum nutrient input requirements for cereals.•Minimum nutrient requirements now in the Global Yield Gap Atlas.•To meet food self-sufficiency by 2050, sub-Saharan Africa maize output must increase upto 4 fold.•Producing sufficient maize on current farmland requires upto 15-fold rise in N input.•Increased N inputs should be matched with management to raise N use efficiency and curb soil degradation in sub-Saharan Africa.
Non-inversion tillage (NIT) is often recommended as a soil conservation measure, protecting soil structure and soil life and preventing erosion. As the adoption of this measure is still below policy ...targets in many European regions, this study aimed at gaining insights in constraints and drivers of implementing NIT to understand how to stimulate behavioural change. This study uses the theory of planned behaviour as a framework for understanding farmers’ decisions on applying NIT. This framework was applied in 8 case studies from 8 Farm Type Zones (FTZ) spread over 4 European countries (Belgium, the Netherlands, Germany and Italy). We used a sequential mixed method, starting with qualitative semi-structured interviews followed by a quantitative survey. Our results show varying adoption rates ranging from 19% to more than 80% across the FTZs. There are large differences between FTZs and even more between countries regarding the number and nature of enabling and hampering factors identified. Although our results do reveal some widely acknowledged advantages and constraints (such as less labour/fuel needs and more weeds), several of them are restricted to one or only some of the FTZs. Some of the conditions favouring or discouraging NIT are related to biophysical characteristics of the FTZs. Besides these biophysical characteristics, agricultural specialization and especially the crops cultivated influence the decision whether or not to plough. Also timing of sowing and harvest of particular crops influences farmers’ perceptions on the ease or difficulty to apply NIT. Finally, cultural, political and socio-economic conditions of the regions are influencing adoption behaviour of the farmers, e.g. good results with ploughing, having nice-looking fields, availability of equipment, the existence of subsidies and the opinion of referents influence the decision whether or not to implement NIT in the singular FTZs. These insights in context-specific enabling and disabling conditions are helpful in defining targeted actions to stimulate adoption in a given region. This paper concludes with an overview of how the resulting insights in farmers’ behaviour might contribute in addressing effective intervention strategies to increase adoption of NIT.
Alternative management practices such as no‐tillage compared to conventional tillage are expected to recover or increase soil quality and productivity, even though all of these aspects are rarely ...studied together. Long‐term field experiments (LTEs) enable analysis of alternative management practices over time. This study investigated a total of 251 European LTEs in which alternative management practices such as crop rotation, catch crops, cover crops/green manure, no‐tillage, non‐inversion tillage and organic fertilization were applied. Response ratios of indicators for soil quality, climate change and productivity between alternative and reference management practices were derived from a total of 260 publications. Both positive and negative effects of alternative management practices on the different indicators were shown and, as expected, no alternative management practice could comply with all objectives simultaneously. Productivity was hampered by non‐inversion tillage, FYM amendments and incorporation of crop residues. SOC contents were increased significantly following organic fertilizers and non‐inversion tillage. GHG emissions were increased by slurry application and incorporation of crop residues. Our study showed that alternative management practices beneficial to one group of indicators (e.g. organic fertilizers for biological soil quality indicators) are not necessarily beneficial to other indicators (e.g. increase of crop yields). We conclude that LTEs are valuable for finding ways forward in protecting European soils as well as finding evidence‐based alternative management practices for the future; however, experiments should focus more on biological soil quality indicators as well as GHG emissions to enable better evaluation of trade‐offs and mutual benefits of management practices.
•Drivers for using organic inputs are improved soil quality and positive social norms.•Barriers are financial and technical issues or related to crop protection.•Financial benefits from using organic ...inputs are uncertain.•More research is needed on links between organic inputs and weeds, pests and diseases.
Soil organic matter (SOM) in agricultural soils builds up via – among others - the use of organic inputs such as straw, compost, farmyard manure or the cultivation of green manures or cover crops. SOM has benefits for long-term soil fertility and can provide ecosystem services. Farmer behaviour is however known to be motivated by a larger number of factors. Using the theory of planned behaviour, we aimed to disentangle these factors. We addressed the following research question: What are currently the main drivers and barriers for arable farmers in Europe to use organic inputs?
Our study focuses on six agro-ecological zones in four European countries (Austria, Flanders Belgium, Italy and the Netherlands) and four practices (straw incorporation, green manure or cover crops, compost and farmyard manure). In a first step, relevant factors were identified for each practice with farmers using 5 to ten semi-structured interviews per agro-ecological zone. In a second step, the relevance of these factors was quantified and they were classified as either drivers or barriers in a large scale farm survey with 1263 farmers.
In the semi-structured interviews, 110 factors that influenced farmer decisions to use an organic input were identified. In the larger farm survey, 60% of the factors included were evaluated as drivers, while 40% were evaluated as barriers for the use of organic inputs. Major drivers to use organic inputs were related to the perceived effects on soil quality (such as improved soil structure or reduced erosion) and the positive influence from social referents (such as fellow farmers or agricultural advisors). Major barriers to use organic inputs were financial (increased costs or foregone income) and perceived effects on crop protection (such as increased weeds, pests and diseases, or increased pesticide use).
Our study shows that motivating farmers to use organic inputs requires specific guidance on how to adapt cultivation practices to reduce weeds, pests and diseases for specific soil types, weather conditions, and crops. In addition, more research is needed on the long-term financial consequences of using organic inputs.
Carbon dioxide capture is essential to achieve net-zero emissions. A hurdle to the design of improved capture materials is the lack of adequate tools to characterise how CO
adsorbs. Solid-state ...nuclear magnetic resonance (NMR) spectroscopy is a promising probe of CO
capture, but it remains challenging to distinguish different adsorption products. Here we perform a comprehensive computational investigation of 22 amine-functionalised metal-organic frameworks and discover that
O NMR is a powerful probe of CO
capture chemistry that provides excellent differentiation of ammonium carbamate and carbamic acid species. The computational findings are supported by
O NMR experiments on a series of CO
-loaded frameworks that clearly identify ammonium carbamate chain formation and provide evidence for a mixed carbamic acid - ammonium carbamate adsorption mode. We further find that carbamic acid formation is more prevalent in this materials class than previously believed. Finally, we show that our methods are readily applicable to other adsorbents, and find support for ammonium carbamate formation in amine-grafted silicas. Our work paves the way for investigations of carbon capture chemistry that can enable materials design.
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