29 research outputs found
Zouttolerantie aardappelen SWAP-WOFOST toepassing op Zilt Proefbedrijf Texel
Op het Zilt Proefbedrijf Texel ‘SaltFarm Texel’ (www.SaltFarmTexel.com) worden proeven uitgevoerd om voor verschillende landbouwgewassen de zouttolerantie te onderzoeken. Gedurende de periode 2012 tot en met 2015 zijn onder gecontroleerde veldomstandigheden de zouttolerantie van de aardappelvariëteiten Miss Mignonne en Achilles vastgesteld (De Vos et al., 2016). In dit rapport wordt beschreven in hoeverre het model SWAP-WOFOST (Kroes et al., 2009) de meetgegevens van het Zilt Proefbedrijf Texel kan simuleren. In het laatste hoofdstuk wordt beknopt beschreven hoe met deze kennis metarelaties kunnen worden afgeleid voor het bepalen van de langjarig gemiddelde opbrengstderving als gevolg van zout schade
Scientists' warning on climate change and insects
Climate warming is considered to be among the most serious of anthropogenic stresses to the environment, because it not only has direct effects on biodiversity, but it also exacerbates the harmful effects of other human-mediated threats. The associated consequences are potentially severe, particularly in terms of threats to species preservation, as well as in the preservation of an array of ecosystem services provided by biodiversity. Among the most affected groups of animals are insects—central components of many ecosystems—for which climate change has pervasive effects from individuals to communities. In this contribution to the scientists' warning series, we summarize the effect of the gradual global surface temperature increase on insects, in terms of physiology, behavior, phenology, distribution, and species interactions, as well as the effect of increased frequency and duration of extreme events such as hot and cold spells, fires, droughts, and floods on these parameters. We warn that, if no action is taken to better understand and reduce the action of climate change on insects, we will drastically reduce our ability to build a sustainable future based on healthy, functional ecosystems. We discuss perspectives on relevant ways to conserve insects in the face of climate change, and we offer several key recommendations on management approaches that can be adopted, on policies that should be pursued, and on the involvement of the general public in the protection effort
Rising rural body-mass index is the main driver of the global obesity epidemic in adults
Body-mass index (BMI) has increased steadily in most countries in parallel with a rise in the proportion of the population who live in cities 1,2 . This has led to a widely reported view that urbanization is one of the most important drivers of the global rise in obesity 3�6 . Here we use 2,009 population-based studies, with measurements of height and weight in more than 112 million adults, to report national, regional and global trends in mean BMI segregated by place of residence (a rural or urban area) from 1985 to 2017. We show that, contrary to the dominant paradigm, more than 55 of the global rise in mean BMI from 1985 to 2017�and more than 80 in some low- and middle-income regions�was due to increases in BMI in rural areas. This large contribution stems from the fact that, with the exception of women in sub-Saharan Africa, BMI is increasing at the same rate or faster in rural areas than in cities in low- and middle-income regions. These trends have in turn resulted in a closing�and in some countries reversal�of the gap in BMI between urban and rural areas in low- and middle-income countries, especially for women. In high-income and industrialized countries, we noted a persistently higher rural BMI, especially for women. There is an urgent need for an integrated approach to rural nutrition that enhances financial and physical access to healthy foods, to avoid replacing the rural undernutrition disadvantage in poor countries with a more general malnutrition disadvantage that entails excessive consumption of low-quality calories. © 2019, The Author(s)
Nitrogen losses to surface waters from intensively managed grassland on sandy soils: the impact of bufferstrips
Nitrogen losses to surface waters from intensively managed grassland on sandy soils: the impact of bufferstrips
Simulation nitrogen-limited crop growth with SWAP/WOFOST : process descriptions and user manual
This report describes a soil nitrogen module (Soil-N), which is combined with the agro-hydrological model, SWAP, and the crop growth model, WOFOST. The core of the Soil-N module is a description of the nitrogen cycle, which is coupled to the organic matter cycle based upon the RothC-26.3 model. Nitrogen can be supplied to the soil as different types of fertilizer applications and through mineralisation of organic nitrogen. Ammonium and nitrate balances are calculated including uptake by plant roots, de-nitrification and leaching of nitrate. Data exchange is on a daily base. The partitioning of nitrogen within crops and the nitrogen contents of crop residues are calculated by WOFOST and passed to the Soil-N module. SWAP generates the data for establishing the water balance of the soil compartment for which the Soil-N perform the simulations. Nitrogen uptake by the crop is calculated as the minimum of the demand by the crop and the availability of nitrogen in the soil. The crop production rate is reduced when the mineral nitrogen stock is limited. Nitrogen-fixation is based on a simple approach. An improved sub-model for phenological stages of soybean was implemented. Increasing atmospheric CO2 concentrations can be accounted for. The innovated integrated model was tested using data sets from The Netherlands, China and Argentina, for which examples are given. This new model can be used as a tool in studies, in which both water and nitrogen can be limited for crop growth
Bodemfysische gegevens in BIS
Bodemfysische gegevens, zoals de waterretentiekarakteristiek en doorlatendheidskarakteristiek, organisch stofgehalte, textuurgegevens, profielbeschrijving en andere metagegevens zijn belangrijke basisgegevens bij het modelleren van transport van water en opgeloste stoffen in de onverzadigde zone, maar vinden ook tal van andere toepassingen. Omdat er grote behoefte is aan actuele bodemfysische gegevens van hoge kwaliteit en omdat de huidige databases onvoldoende opschalingsmogelijkheden bieden, zijn in dit project 100 nieuwe bodemfysische gegevens van goede kwaliteit gegenereerd. De bodemfysische gegevens en de bijbehorende beschrijvende gegevens zijn ondergebracht in het BIS (Bodem Informatie Systeem). Aanvullend is van 91 bestaande bodemfysische gegevens van hoge kwaliteit in Priapus een koppeling gelegd met beschrijvende gegevens in BIS en de literatuur, zodat er in totaal 191 bodemfysische monsters beschikbaar zijn