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Sokrat Sinaj - One of the best experts on this subject based on the ideXlab platform.

  • spatial variability of potassium in agricultural soils of the canton of fribourg switzerland
    Geoderma, 2017
    Co-Authors: Guillaume Blanchet, Zamir Libohova, Nicolas Rossier, Stéphane Joost, B Jeangros, Andre Schneider, Sokrat Sinaj
    Abstract:

    Abstract Potassium (K) is a crucial element for plant nutrition and its availability and spatial distribution in agricultural soils is influenced by many agro-environmental factors. In Switzerland, a soil monitoring network (FRIBO) was established in 1987 with 250 sites distributed over the whole of the canton of Fribourg (representing 4% of the surface area of Switzerland), whose territory is shared between the Swiss Midlands and the Western Alp foothills. In this study area, diverse geological deposits (sandstone, marlstone, silts and calcareous rocks), soil types (Cambisols, Gleysols, Rendzinas, Luvisols and Fluvisols) and land uses (cropland, Permanent grassland and mountain pasture) are present, making the network interesting for assessing the relative contribution of environmental variables and land use management on soil properties. The aims of the present study were to (i) characterize the soil K status in the Fribourg canton according to four different extraction methods; (ii) analyse the spatial variability of soil K in relation to land use, soil type, soil parent material and topography; (iii) evaluate the spatial predictability of K at the canton level; and (iv) analyse the implications for K fertilization management. The overall amount of soil total K averaged 13.6 g·kg − 1 with significant variations across the sites (5.1–22.1 g·kg − 1 ). The spatial distribution of total K content was influenced by relatively extended soil forming processes, as suggested by (i) a significant global spatial autocorrelation measure at the 10 km scale (Moran's I  = 0.43); (ii) significant differences observed among soil types and soil parent materials and (iii) significant correlations with land attributes such as elevation ( r  = − 0.51). On the other hand, available mean K forms were significantly different among land uses, with the highest mean values of available K encountered in Permanent Grasslands, from 46.3 mg·kg − 1 (water extraction) to 198 mg·kg − 1 (acetate ammonium + EDTA extraction). All K forms (total and available) showed similar spatial regional patterns for all spatial interpolation methods, with areas dominated by Permanent grassland and crops presenting higher values. However, these trends were less pronounced for the available K forms due to the prevalence of on-farm management practices for these K forms ( e.g. fertilization), likely inducing high spatial and temporal variability. This hypothesis was supported by spatial clustering of low and/or high K fertility status that could be related to local particular farming practices. Grasslands require particular attention with regard to overall high K fertility status.

  • spatial variability of soil phosphorus in the fribourg canton switzerland
    Geoderma, 2014
    Co-Authors: Aurelien Roger, Zamir Libohova, Nicolas Rossier, Stéphane Joost, Alexandra Maltas, Emmanuel Frossard, Sokrat Sinaj
    Abstract:

    Phosphorus (P) is the second essential nutrient for plant growth but can become an ecological and economical concern in case of over-fertilization. Soil P dynamic is influenced by many parameters like soil physical-chemical properties and farming practices. A better understanding of the factors controlling its distribution is required to achieve best P crops management. In Switzerland, the FRIBO network was launched in 1987 and comprises of 250 sites covering a wide diversity of soils and three different land uses (croplands, Grasslands and mountain pastures) across the Fribourg canton. A spatial investigation of the different P forms for the FRIBO network led to the following main conclusions: i) The P status in agricultural soils was significantly different among the three land uses encountered, with the highest mean values of available P found in croplands (from 2.12 to 81.3 mg.kg-1 according to the indicator used), whereas total P was more abundant in Permanent Grasslands (1186.2 mg.kg-1), followed by mountain pastures (1039.0 mg.kg-1) and croplands (935.0 mg.kg-1). A full characterization of the soil P status provides necessary data on P distribution related to soil properties and land use, and should help to develop more accurate estimation procedures and fertilization strategies in a near future; ii) Environmental variables derived from digital elevation model (DEM) only explained a small part of the spatial variation of the different P forms (20 to 25%). Thus, the geostatistic analyses revealed that land use play a major role in soil P distribution. However, this pattern was less visible for total P than for available P. Future studies should include more data points as well as additional variables such as parent material and soil type to accurately estimate the role of soil parameters on the distribution of P-related forms.

Alexandre Uttle - One of the best experts on this subject based on the ideXlab platform.

  • nutrient limitations induced by drought affect forage n and p differently in two Permanent Grasslands
    Agriculture Ecosystems & Environment, 2019
    Co-Authors: Marco Meisse, Amarante Vitra, Claire Deleglise, Sebastie Dubois, Massimiliano Probo, Eric Mosima, Alexandre Uttle
    Abstract:

    Abstract Drought events can strongly affect ecosystem functioning by modifying relationship between plants, microbes and soil chemistry, with consequent impacts on nutrient cycling. However, the potential impacts of a soil moisture reduction on the nitrogen (N) and phosphorus (P) cycling in Grasslands remain poorly understood, especially in regard to forage production. To fill this knowledge gap, a drought experiment was carried out using rainout shelters in two Permanent Grasslands, characterized by similar vegetation communities but contrasted soil nutrient limitations. Drought treatments were applied during two months, either when plant growth was highest (Early-season drought) or after the peak of biomass production (Late-season drought). Dry matter production, forage N status (NNI) and P content as well as N and P contents in microbial biomass and soil were determined. Both early and late-season drought significantly reduced soil moisture during the vegetation growth period. Forage yield was also reduced by drought, but only when it occurred late in the season. Using a structural equation model, we showed that soil moisture reduction had a direct effect on forage N status, suggesting that water shortage induced lower transpiration and water fluxes. Soil moisture reduction also affected forage P by reducing the availability of soil P. However, other mechanisms played a larger role and were site-specific. At the more fertile site, reduction in soil moisture directly impaired forage P, suggesting that water stress mainly resulted in lower diffusion rates to roots, while at the less fertile site, an indirect reduction of forage P through a pathway implying microbes (decrease in microbial P) was detected. Our results suggest that the two Grasslands suffered mainly from water shortage per se, but also from drought-induced nutrient deficiency (mainly P), which amplified yield losses and further decreased forage quality. Overall, our findings emphasize the need for further research on the plant-soil-microbe system functioning, in order to secure a sustainable and resilient forage production in the context of climate change.

Valenti H Klaus - One of the best experts on this subject based on the ideXlab platform.

  • land use intensity rather than plant species richness affects the leaching risk of multiple nutrients from Permanent Grasslands
    Global Change Biology, 2018
    Co-Authors: Valenti H Klaus, Till Kleinebecke, Verena Usch, Markus Fische, Norbe Holzel, Sascha Nowak, Daniel Prati, Deborah Schafe, Ingo Schoning
    Abstract:

    The intensification of land use constitutes one of the main drivers of global change and alters nutrient fluxes on all spatial scales, causing landscape-level eutrophication and contamination of natural resources. Changes in soil nutrient concentrations are thus indicative for crucial environmental issues associated with intensive land use. We measured concentrations of NO3 -N, NH4 -N, P, K, Mg, and Ca using 1,326 ion-exchange resin bags buried in 20 cm depth beneath the main root zone in 150 temperate Grasslands. Nutrient concentrations were related to land use intensity, that is, fertilization, mowing, grazing intensities, and plant diversity by structural equation modeling. Furthermore, we assessed the response of soil nutrients to mechanical sward disturbance and subsequent reseeding, a common practice for grassland renewal. Land use intensity, especially fertilization, significantly increased the concentrations of NO3 -N, NH4 -N, K, P, and also Mg. Besides fertilization (and tightly correlated mowing) intensity, grazing strongly increased NO3 -N and K concentrations. Plant species richness decreased P and NO3 -N concentrations in soil when grassland productivity of the actual year was statistically taken into account, but not when long-term averages of productivity were used. Thus, we assume that, in the actual study year, a distinct drought period might have caused the observed decoupling of productivity from fertilization and soil nutrients. Breaking up the grassland sward drastically increased NO3 -N concentrations (+146%) but reduced NH4 -N, P, and K concentrations, unbalancing soil nutrient stoichiometry and boosting the risk of N leaching. Reseeding the sward after disturbance did not have a short-term effect on nutrient concentrations. We conclude that renewal of Permanent grassland should be avoided as far as possible and future grassland management has to strongly rise the effectiveness of fertilization. Additionally, grassland management might have to increasingly taking care of periods of drought, in which nutrient additions might not increase plant growth but potentially only facilitate leaching.

Zamir Libohova - One of the best experts on this subject based on the ideXlab platform.

  • spatial variability of potassium in agricultural soils of the canton of fribourg switzerland
    Geoderma, 2017
    Co-Authors: Guillaume Blanchet, Zamir Libohova, Nicolas Rossier, Stéphane Joost, B Jeangros, Andre Schneider, Sokrat Sinaj
    Abstract:

    Abstract Potassium (K) is a crucial element for plant nutrition and its availability and spatial distribution in agricultural soils is influenced by many agro-environmental factors. In Switzerland, a soil monitoring network (FRIBO) was established in 1987 with 250 sites distributed over the whole of the canton of Fribourg (representing 4% of the surface area of Switzerland), whose territory is shared between the Swiss Midlands and the Western Alp foothills. In this study area, diverse geological deposits (sandstone, marlstone, silts and calcareous rocks), soil types (Cambisols, Gleysols, Rendzinas, Luvisols and Fluvisols) and land uses (cropland, Permanent grassland and mountain pasture) are present, making the network interesting for assessing the relative contribution of environmental variables and land use management on soil properties. The aims of the present study were to (i) characterize the soil K status in the Fribourg canton according to four different extraction methods; (ii) analyse the spatial variability of soil K in relation to land use, soil type, soil parent material and topography; (iii) evaluate the spatial predictability of K at the canton level; and (iv) analyse the implications for K fertilization management. The overall amount of soil total K averaged 13.6 g·kg − 1 with significant variations across the sites (5.1–22.1 g·kg − 1 ). The spatial distribution of total K content was influenced by relatively extended soil forming processes, as suggested by (i) a significant global spatial autocorrelation measure at the 10 km scale (Moran's I  = 0.43); (ii) significant differences observed among soil types and soil parent materials and (iii) significant correlations with land attributes such as elevation ( r  = − 0.51). On the other hand, available mean K forms were significantly different among land uses, with the highest mean values of available K encountered in Permanent Grasslands, from 46.3 mg·kg − 1 (water extraction) to 198 mg·kg − 1 (acetate ammonium + EDTA extraction). All K forms (total and available) showed similar spatial regional patterns for all spatial interpolation methods, with areas dominated by Permanent grassland and crops presenting higher values. However, these trends were less pronounced for the available K forms due to the prevalence of on-farm management practices for these K forms ( e.g. fertilization), likely inducing high spatial and temporal variability. This hypothesis was supported by spatial clustering of low and/or high K fertility status that could be related to local particular farming practices. Grasslands require particular attention with regard to overall high K fertility status.

  • spatial variability of soil phosphorus in the fribourg canton switzerland
    Geoderma, 2014
    Co-Authors: Aurelien Roger, Zamir Libohova, Nicolas Rossier, Stéphane Joost, Alexandra Maltas, Emmanuel Frossard, Sokrat Sinaj
    Abstract:

    Phosphorus (P) is the second essential nutrient for plant growth but can become an ecological and economical concern in case of over-fertilization. Soil P dynamic is influenced by many parameters like soil physical-chemical properties and farming practices. A better understanding of the factors controlling its distribution is required to achieve best P crops management. In Switzerland, the FRIBO network was launched in 1987 and comprises of 250 sites covering a wide diversity of soils and three different land uses (croplands, Grasslands and mountain pastures) across the Fribourg canton. A spatial investigation of the different P forms for the FRIBO network led to the following main conclusions: i) The P status in agricultural soils was significantly different among the three land uses encountered, with the highest mean values of available P found in croplands (from 2.12 to 81.3 mg.kg-1 according to the indicator used), whereas total P was more abundant in Permanent Grasslands (1186.2 mg.kg-1), followed by mountain pastures (1039.0 mg.kg-1) and croplands (935.0 mg.kg-1). A full characterization of the soil P status provides necessary data on P distribution related to soil properties and land use, and should help to develop more accurate estimation procedures and fertilization strategies in a near future; ii) Environmental variables derived from digital elevation model (DEM) only explained a small part of the spatial variation of the different P forms (20 to 25%). Thus, the geostatistic analyses revealed that land use play a major role in soil P distribution. However, this pattern was less visible for total P than for available P. Future studies should include more data points as well as additional variables such as parent material and soil type to accurately estimate the role of soil parameters on the distribution of P-related forms.

Nicolas Rossier - One of the best experts on this subject based on the ideXlab platform.

  • spatial variability of potassium in agricultural soils of the canton of fribourg switzerland
    Geoderma, 2017
    Co-Authors: Guillaume Blanchet, Zamir Libohova, Nicolas Rossier, Stéphane Joost, B Jeangros, Andre Schneider, Sokrat Sinaj
    Abstract:

    Abstract Potassium (K) is a crucial element for plant nutrition and its availability and spatial distribution in agricultural soils is influenced by many agro-environmental factors. In Switzerland, a soil monitoring network (FRIBO) was established in 1987 with 250 sites distributed over the whole of the canton of Fribourg (representing 4% of the surface area of Switzerland), whose territory is shared between the Swiss Midlands and the Western Alp foothills. In this study area, diverse geological deposits (sandstone, marlstone, silts and calcareous rocks), soil types (Cambisols, Gleysols, Rendzinas, Luvisols and Fluvisols) and land uses (cropland, Permanent grassland and mountain pasture) are present, making the network interesting for assessing the relative contribution of environmental variables and land use management on soil properties. The aims of the present study were to (i) characterize the soil K status in the Fribourg canton according to four different extraction methods; (ii) analyse the spatial variability of soil K in relation to land use, soil type, soil parent material and topography; (iii) evaluate the spatial predictability of K at the canton level; and (iv) analyse the implications for K fertilization management. The overall amount of soil total K averaged 13.6 g·kg − 1 with significant variations across the sites (5.1–22.1 g·kg − 1 ). The spatial distribution of total K content was influenced by relatively extended soil forming processes, as suggested by (i) a significant global spatial autocorrelation measure at the 10 km scale (Moran's I  = 0.43); (ii) significant differences observed among soil types and soil parent materials and (iii) significant correlations with land attributes such as elevation ( r  = − 0.51). On the other hand, available mean K forms were significantly different among land uses, with the highest mean values of available K encountered in Permanent Grasslands, from 46.3 mg·kg − 1 (water extraction) to 198 mg·kg − 1 (acetate ammonium + EDTA extraction). All K forms (total and available) showed similar spatial regional patterns for all spatial interpolation methods, with areas dominated by Permanent grassland and crops presenting higher values. However, these trends were less pronounced for the available K forms due to the prevalence of on-farm management practices for these K forms ( e.g. fertilization), likely inducing high spatial and temporal variability. This hypothesis was supported by spatial clustering of low and/or high K fertility status that could be related to local particular farming practices. Grasslands require particular attention with regard to overall high K fertility status.

  • spatial variability of soil phosphorus in the fribourg canton switzerland
    Geoderma, 2014
    Co-Authors: Aurelien Roger, Zamir Libohova, Nicolas Rossier, Stéphane Joost, Alexandra Maltas, Emmanuel Frossard, Sokrat Sinaj
    Abstract:

    Phosphorus (P) is the second essential nutrient for plant growth but can become an ecological and economical concern in case of over-fertilization. Soil P dynamic is influenced by many parameters like soil physical-chemical properties and farming practices. A better understanding of the factors controlling its distribution is required to achieve best P crops management. In Switzerland, the FRIBO network was launched in 1987 and comprises of 250 sites covering a wide diversity of soils and three different land uses (croplands, Grasslands and mountain pastures) across the Fribourg canton. A spatial investigation of the different P forms for the FRIBO network led to the following main conclusions: i) The P status in agricultural soils was significantly different among the three land uses encountered, with the highest mean values of available P found in croplands (from 2.12 to 81.3 mg.kg-1 according to the indicator used), whereas total P was more abundant in Permanent Grasslands (1186.2 mg.kg-1), followed by mountain pastures (1039.0 mg.kg-1) and croplands (935.0 mg.kg-1). A full characterization of the soil P status provides necessary data on P distribution related to soil properties and land use, and should help to develop more accurate estimation procedures and fertilization strategies in a near future; ii) Environmental variables derived from digital elevation model (DEM) only explained a small part of the spatial variation of the different P forms (20 to 25%). Thus, the geostatistic analyses revealed that land use play a major role in soil P distribution. However, this pattern was less visible for total P than for available P. Future studies should include more data points as well as additional variables such as parent material and soil type to accurately estimate the role of soil parameters on the distribution of P-related forms.