Search results for "Stain"

2020

AbstractForecasting crop yields is becoming increasingly important under the current context in which food security needs to be ensured despite the challenges brought by climate change, an expanding world population accompanied by rising incomes, increasing soil erosion, and decreasing water resources. Temperature, radiation, water availability and other environmental conditions influence crop growth, development, and final grain yield in a complex nonlinear manner. Machine learning (ML) techniques, and deep learning (DL) methods in particular, can account for such nonlinear relations between yield and its covariates. However, they typically lack transparency and interpretability, since the…

Land use intensification increasingly drives the spatiotemporal patterns of the global human appropriation of net primary production in the last cent…

2021

Land use has greatly transformed Earth's surface. While spatial reconstructions of how the extent of land cover and land-use types have changed during the last century are available, much less information exists about changes in land-use intensity. In particular, global reconstructions that consistently cover land-use intensity across land-use types and ecosystems are missing. We, therefore, lack understanding of how changes in land-use intensity interfere with the natural processes in land systems. To address this research gap, we map land-cover and land-use intensity changes between 1910 and 2010 for 9 points in time. We rely on the indicator framework of human appropriation of net primar…

Errors and uncertainties introduced by a regional climate model in climate impact assessments: example of crop yield simulations in West Africa

2015

16 pages; International audience; The challenge of estimating the potential impacts of climate change has led to an increasing use of dynamical downscaling to produce fine spatial-scale climate projections for impact assessments. In this work, we analyze if and to what extent the bias in the simulated crop yield can be reduced by using the Weather Research and Forecasting (WRF) regional climate model to downscale ERA-Interim (European Centre for Medium-Range Weather Forecasts (ECMWF) Re-Analysis) rainfall and radiation data. Then, we evaluate the uncertainties resulting from both the choice of the physical parameterizations of the WRF model and its internal variability. Impact assessments w…

Impacts and adaptation options of climate change on ecosystem services in Finland: a model based study

2013

At a global level, it is estimated that nearly two-thirds of ecosystem services have been degraded in just fifty years. The additional stresses imposed by climate change will require extraordinary adaptation. This paper synthesises main result of a large Finnish project studying the vulnerability of key ecosystem services to climate change and the possibilities for the individual sectors to adapt to these changes. The project based its work on data and infrastructures of nine intensively studied areas belonging to the Finnish LTER (Long-Term Ecological Research) network. The methods developed and used included remote sensing, derivation of impact scenarios, dynamic modelling, laboratory exp…

Emerging extraction

2015

Traditional extraction methods include usually high temperature treatment (more than 100°C) with the subsequent risk of thermal denaturation or transformation of the target molecules. Moreover, these techniques are very time-consuming and require relatively large quantities of solvents. On the other hand, the use of environmentally friendly technologies has led researchers and the food industry to develop new alternative processes that can extract valuable compounds from different sources and food wastes of different origin. This chapter describes the potential use of emerging technologies such as ultrasound-assisted extraction (UAE), laser ablation, pulsed electric fields (PEF), high volta…

2017

AbstractFuture changes in the structure of daily rainfall, especially the number of rainy days and the intensity of extreme events, are likely to induce major impacts on rain-fed agriculture in the tropics. In Africa this issue is of primary importance, but the agreement between climate models to simulate such descriptors of rainfall is generally poor. Here, we show that the climate models used for the fifth assessment report of IPCC simulate a marked decrease in the number of rainy days, together with a strong increase in the rainfall amounts during the 1% wettest days, by the end of the 21st century over Southern Africa. These combined changes lead to an apparent stability of seasonal tot…

Benefits of soil carbon: report on the outcomes of an international scientific committee on problems of the environment rapid assessment workshop

2014

The outcomes of the discussion in the four working sessions showed that although there is an urgent need to improve soil carbon management and stocks, and despite the existing knowledge about good agricultural practices to achieve this goal, these are not put into practice effectively and globally. The apparent contradiction has to do with a mismatch of policies at different societal and geographical scales, and the low policy profile of SOC. All participants agreed in the need to bring SOC into the core of environmental policies at all levels and to improve the governance of policy actions by addressing the stakeholders in a more effective way. Fil: Banwart, Steven. University of Sheffield…

The impact of urban development on aquifers in large coastal cities of West Africa: Present status and future challenges

2018

Abstract This paper investigates the coastal cities of Abidjan, Cotonou, Lagos and Douala in West Africa. Published data on these areas were aggregated in order to compare the urban development of some African huge cities and assess their impacts on groundwater. Those urban centers have experienced an exponential demographic expansion since the 1950s, with increased population densities and a geographical coverage expansion as well. The Continental Terminal aquifer, major groundwater resource taped in this region by the national water companies and local populations, shows a continuous downward trend in piezometric levels. Concerning water quality, the evolution up to the current state (sal…

Effects of the COVID-19 Pandemic on Sports Entrepreneurship

2020

Sports entrepreneurship has been considered an important part of sports organisations when overcoming crisis situations. The aim of this study is to determine the impact of the crisis derived from COVID-19 on sports entrepreneurship and whether there are differences in the prediction of entrepreneurship on service quality in non-profit sports clubs. To this end, 145 sports clubs were analysed before and after the outbreak of the virus in society. Paired sample-t tests were carried out to determine the differences in variables studied before (Time I) and after (Time II) the COVID-19 outbreak, and correlations and hierarchical linear regressions were used to analyse the relationship between t…

The UK needs a sustainable strategy for COVID-19

2020

The UK is well into the second wave of COVID-19, with 60 051 lives lost to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection to date, according to provisional data from the Office for National Statistics. Official UK Government data show that cases have been rising exponentially since late August, 2020, with increases across all regions in England in recent weeks.As of Nov 4, 2020, the UK had 25 177 confirmed daily cases. These are almost certainly underestimates as between Oct 17 and Oct 23, 2020, England alone had 52 000 estimated daily cases.Estimates of the effective reproduction number in England vary between 1.1 and 1.6.Daily deaths have doubled every fortnight si…