LIVIVO - The Search Portal for Life Sciences

zur deutschen Oberfläche wechseln
Advanced search

Search results

Result 1 - 10 of total 112

Search options

  1. Book ; Online: Global maps of agricultural expansion potential at a 300 m resolution

    Čengić, M. / Steinmann, Zoran / Defourny, P. / Doelman, Jonathan / Lamarche, Céline / Stehfest, Elke / Schipper, Aafke M. / Huijbregts, Mark A.J.

    2023  

    Abstract: Global maps of agricultural expansion potential at a 300 m resolution This repository contains data from “Global maps of agricultural expansion potential at a 300 m resolution” study. Abstract: The global expansion of agricultural land is a leading ... ...

    Abstract Global maps of agricultural expansion potential at a 300 m resolution This repository contains data from “Global maps of agricultural expansion potential at a 300 m resolution” study. Abstract: The global expansion of agricultural land is a leading driver of climate change and biodiversity loss. However, the spatial resolution of current global land change models is relatively coarse, which limits environmental impact assessments. To address this issue, we developed global maps representing the potential for conversion into agricultural land at a resolution of 10 arc-seconds (approximately 300 m at the equator). We created the maps using Artificial Neural Network (ANN) models relating locations of recent past conversions (2007-2020) into one of three cropland categories (cropland only, mosaics with >50% crops, and mosaics with 50% crops, and (iii) mosaics with 50% crops, and mosaics with 50% crops, and 40 - mosaics with 50% crops category at the spatial resolution of 10 arc-seconds. - “Agri_potential_mosaic_40.tif” is the global raster map for mosaics with 50% crops, and category 40 is mosaics with
    Keywords GLOBIO ; Land cover change ; agriculture ; biodiversity ; cropland ; deforestation ; integrated assessment models ; sustainability
    Subject code 333
    Publisher Radboud Universiteit
    Publishing country nl
    Document type Book ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

    More links

    Kategorien

  2. Article: In-Season Potato Crop Nitrogen Status Assessment from Satellite and Meteorological Data

    Goffart, D. / Abdallah, F. Ben / Curnel, Y. / Planchon, V. / Defourny, P. / Goffart, J.-P.

    Potato research. 2022 Sept., v. 65, no. 3

    2022  

    Abstract: For a conventional potato crop, splitting nitrogen (N) application is recognised as an efficient strategy to improve tuber yield and quality and to mitigate N losses to the environment. This approach requires the assessment of in-season crop N status for ...

    Abstract For a conventional potato crop, splitting nitrogen (N) application is recognised as an efficient strategy to improve tuber yield and quality and to mitigate N losses to the environment. This approach requires the assessment of in-season crop N status for decisions on supplemental mineral N fertiliser application. This study focuses on the assessment of potato crop biophysical variables useful to establish crop N status. Field, satellite and meteorological data were collected in farmer’s fields during 3 years (2017–2019) with contrasted meteorological conditions. Degree days (DD) and water balance from planting date were computed from meteo data, and a selection of relevant vegetation indices (VIs) was derived from Sentinel-2 reflectance. Multiple linear regression (MLR) and random forest regression (RFR) models predicting shoots biomass, shoots N content and shoots N uptake from a combination of meteo and/or satellite-based variables were defined and evaluated. The best combinations integrate DD and two to four VIs and perform with cross-validation RMSE of about 0.38 DM t ha⁻¹, 0.41%, 21 kg ha⁻¹ for MLR and 0.32 DM t ha⁻¹, 0.31%, 19 kg ha⁻¹ for RFR. Despite these performances, MLR was shown to be more robust. From these estimated variables, two methods are proposed to derive total N uptake and nitrogen nutrition index. The most relevant method uses shoots N uptake and biomass. It allows future estimation of in-season supplemental N fertiliser to be applied to reach a targeted tuber yield.
    Keywords algorithms ; biomass ; farmers ; fertilizer application ; meteorological data ; nitrogen ; nitrogen fertilizers ; nutrition ; potatoes ; reflectance ; regression analysis ; research ; satellites ; total nitrogen ; vegetation
    Language English
    Dates of publication 2022-09
    Size p. 729-755.
    Publishing place Springer Netherlands
    Document type Article
    ZDB-ID 407680-1
    ISSN 1871-4528 ; 0014-3065
    ISSN (online) 1871-4528
    ISSN 0014-3065
    DOI 10.1007/s11540-022-09545-0
    Database NAL-Catalogue (AGRICOLA)

    More links

    Kategorien

  3. Article: Field-scale assessment of Belgian winter cover crops biomass based on Sentinel-2 data

    Goffart, D. / Curnel, Y. / Planchon, V. / Goffart, J.-P. / Defourny, P.

    European journal of agronomy

    2021  Volume 126, Issue -, Page(s) 126278

    Language English
    Document type Article
    ZDB-ID 1157136-6
    ISSN 1161-0301
    Database Current Contents Nutrition, Environment, Agriculture

    More links

    Kategorien

  4. Article ; Online: Ethiopian Crop Type 2020 (EthCT2020)

    Blasch, Gerald / Alemayehu, Yoseph / Lesne, Louise / Wolter, Jolan / Taymans, Matthieu / Tesfaye, Tsegaab / Negash, Tamirat / Andulalem, Mequanint / Gutu, Kitessa / Debela, Megersa / Eshetu, Zerihun / Tesfaye, Kindie / Mottaleb, Khondoker / Defourny, Pierre / Hodson, David P

    Data in brief

    2024  Volume 54, Page(s) 110427

    Abstract: Crop type observation is crucial for various environmental and agricultural remote sensing applications including land use and land cover mapping, crop growth monitoring, crop modelling, yield forecasting, disease surveillance, and climate modelling. ... ...

    Abstract Crop type observation is crucial for various environmental and agricultural remote sensing applications including land use and land cover mapping, crop growth monitoring, crop modelling, yield forecasting, disease surveillance, and climate modelling. Quality-controlled georeferenced crop type information is essential for calibrating and validating machine learning algorithms. However, publicly available field data is scarce, particularly in the highly dynamic smallholder farming systems of sub-Saharan Africa. For the 2020/21 main cropping season (
    Language English
    Publishing date 2024-04-14
    Publishing country Netherlands
    Document type Journal Article
    ZDB-ID 2786545-9
    ISSN 2352-3409 ; 2352-3409
    ISSN (online) 2352-3409
    ISSN 2352-3409
    DOI 10.1016/j.dib.2024.110427
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  5. Book ; Online: Accuracy Requirements for Early Estimation of Crop Production in Senegal

    Jacques, Damien Christophe / Defourny, Pierre

    2019  

    Abstract: Early warning systems for food security rely on timely and accurate estimations of crop production. Several approaches have been developed to get early estimations of area and yield, the two components of crop production. The most common methods, based ... ...

    Abstract Early warning systems for food security rely on timely and accurate estimations of crop production. Several approaches have been developed to get early estimations of area and yield, the two components of crop production. The most common methods, based on Earth observation data, are image classification for crop area and correlation with vegetation index for crop yield. Regardless of the approach used, early estimators of cropland area, crop area or crop yield should have an accuracy providing lower production error than existing historical crop statistics. The objective of this study is to develop a methodological framework to define the accuracy requirements for early estimators of cropland area, crop area and crop yield in Senegal. These requirements are made according to (i) the inter-annual variability and the trend of historical data, (ii) the calendar of official statistics data collection, and (iii) the time at which early estimations of cropland area, crop area and crop yield can theoretically be available. This framework is applied to the seven main crops in Senegal using 20 years of crop production data. Results show that the inter-annual variability of crop yield is the main factor limiting the accuracy of pre-harvest production forecast. Estimators of cropland area can be used to improve production prediction of groundnuts, millet and rice, the three main crops in Senegal stressing the value of cropland mapping for food security. While applied to Senegal, this study could easily be reproduced in any country where reliable agricultural statistics are available.
    Keywords Computer Science - Computers and Society
    Subject code 333
    Publishing date 2019-06-09
    Publishing country us
    Document type Book ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

    More links

    Kategorien

  6. Article: Constraining water limitation of photosynthesis in a crop growth model with sun-induced chlorophyll fluorescence

    De Cannière, S. / Herbst, M. / Vereecken, H. / Defourny, P. / Jonard, F.

    Remote sensing of environment. 2021 Dec. 15, v. 267

    2021  

    Abstract: Water fulfils key roles in maintaining a plant's biological activity. Water shortage induces stomatal closure, causing a reduction in photosynthesis and transpiration rates. Sun-induced chlorophyll fluorescence (SIF) emission is sensitive to subtle, ... ...

    Abstract Water fulfils key roles in maintaining a plant's biological activity. Water shortage induces stomatal closure, causing a reduction in photosynthesis and transpiration rates. Sun-induced chlorophyll fluorescence (SIF) emission is sensitive to subtle, stress-induced variations in non-photochemical quenching and in photosynthetic electron transport, caused by e.g., a fluctuation in the water availability. Based on this sensitivity, a framework for calibrating a water stress function in a crop growth model using ground-based SIF observations is proposed. SIF time series are simulated by coupling the AgroC crop growth model to the Soil Canopy Observations Photosynthesis Energy (SCOPE) model. This allowed parametrizing the water stress function in the AgroC crop growth model, resulting in improved estimates of actual evapotranspiration and net ecosystem exchange over a sugar beet stand during stressed periods. The improvement in the estimation of the water and carbon fluxes by AgroC during the summer months highlights the ability of canopyscale SIF observations to serve as a remote sensing metric to indicate the intensity of a stress condition. We argue that our framework, linking SIF emission to stress functions, can be used to extract information concerning drought stress from the Fluorescence Explorer (FLEX) satellite, scheduled for launch in 2024.
    Keywords bioactive properties ; canopy ; carbon ; chlorophyll ; crop models ; energy ; environment ; evapotranspiration ; fluorescence ; net ecosystem exchange ; photosynthetic electron transport ; satellites ; soil ; stomatal movement ; sugar beet ; summer ; time series analysis ; transpiration ; water shortages ; water stress
    Language English
    Dates of publication 2021-1215
    Publishing place Elsevier Inc.
    Document type Article
    ZDB-ID 431483-9
    ISSN 0034-4257
    ISSN 0034-4257
    DOI 10.1016/j.rse.2021.112722
    Database NAL-Catalogue (AGRICOLA)

    More links

    Kategorien

  7. Book ; Online: The Forests of the Congo Basin

    Eba’a Atyi, R. / Hiol Hiol, F. / Lescuyer, G. / Mayaux, P. / Defourny, P. / Bayol, N. / Saracco, F. / Pokem, D. / Sufo Kankeu, R. / Nasi, R.

    State of the Forests 2021

    2023  

    Keywords forest management ; climate change ; conservation ; ecosystem services
    Language English
    Publishing date 2023-01-24T07:05:29Z
    Publisher CIFOR
    Publishing country fr
    Document type Book ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

    More links

    Kategorien

  8. Article ; Online: Validating a continental-scale groundwater diffuse pollution model using regional datasets.

    Ouedraogo, Issoufou / Defourny, Pierre / Vanclooster, Marnik

    Environmental science and pollution research international

    2017  Volume 26, Issue 3, Page(s) 2105–2119

    Abstract: In this study, we assess the validity of an African-scale groundwater pollution model for nitrates. In a previous study, we identified a statistical continental-scale groundwater pollution model for nitrate. The model was identified using a pan-African ... ...

    Abstract In this study, we assess the validity of an African-scale groundwater pollution model for nitrates. In a previous study, we identified a statistical continental-scale groundwater pollution model for nitrate. The model was identified using a pan-African meta-analysis of available nitrate groundwater pollution studies. The model was implemented in both Random Forest (RF) and multiple regression formats. For both approaches, we collected as predictors a comprehensive GIS database of 13 spatial attributes, related to land use, soil type, hydrogeology, topography, climatology, region typology, nitrogen fertiliser application rate, and population density. In this paper, we validate the continental-scale model of groundwater contamination by using a nitrate measurement dataset from three African countries. We discuss the issue of data availability, and quality and scale issues, as challenges in validation. Notwithstanding that the modelling procedure exhibited very good success using a continental-scale dataset (e.g. R
    MeSH term(s) Africa ; Environmental Monitoring/methods ; Fertilizers/analysis ; Groundwater/chemistry ; Humans ; Models, Statistical ; Multivariate Analysis ; Nitrates/analysis ; Nitrogen ; Reproducibility of Results ; Water Pollutants, Chemical/analysis ; Water Pollution/analysis
    Chemical Substances Fertilizers ; Nitrates ; Water Pollutants, Chemical ; Nitrogen (N762921K75)
    Language English
    Publishing date 2017-12-11
    Publishing country Germany
    Document type Journal Article ; Meta-Analysis ; Validation Studies
    ZDB-ID 1178791-0
    ISSN 1614-7499 ; 0944-1344
    ISSN (online) 1614-7499
    ISSN 0944-1344
    DOI 10.1007/s11356-017-0899-9
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  9. Article ; Online: Optimal sample size and composition for crop classification with Sen2-Agri’s random forest classifier

    Schulthess, Urs / Rodrigues, Francelino / Taymans, Matthieu / Bellemans, Nicolas / Bontemps, Sophie / Ortiz Monasterio, Jose Iván / Gerard, Bruno G. / Defourny, Pierre

    Remote Sensing

    2023  

    Abstract: Sen2-Agri is a software system that was developed to facilitate the use of multi-temporal satellite data for crop classification with a random forest (RF) classifier in an operational setting. It automatically ingests and processes Sentinel-2 and LandSat ...

    Abstract Sen2-Agri is a software system that was developed to facilitate the use of multi-temporal satellite data for crop classification with a random forest (RF) classifier in an operational setting. It automatically ingests and processes Sentinel-2 and LandSat 8 images. Our goal was to provide practitioners with recommendations for the best sample size and composition. The study area was located in the Yaqui Valley in Mexico. Using polygons of more than 6000 labeled crop fields, we prepared data sets for training, in which the nine crops had an equal or proportional representation, called Equal or Ratio, respectively. Increasing the size of the training set improved the overall accuracy (OA). Gains became marginal once the total number of fields approximated 500 or 40 to 45 fields per crop type. Equal achieved slightly higher OAs than Ratio for a given number of fields. However, recall and F-scores of the individual crops tended to be higher for Ratio than for Equal. The high number of wheat fields in the Ratio scenarios, ranging from 275 to 2128, produced a more accurate classification of wheat than the maximal 80 fields of Equal. This resulted in a higher recall for wheat in the Ratio than in the Equal scenarios, which in turn limited the errors of commission of the non-wheat crops. Thus, a proportional representation of the crops in the training data is preferable and yields better accuracies, even for the minority crops.
    Keywords crops ; forests ; machine learning ; agriculture ; remote sensing
    Language English
    Publishing date 2023-02-03T08:30:07Z
    Publisher MDPI
    Publishing country fr
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

    More links

    Kategorien

  10. Article ; Online: Global Maps of Agricultural Expansion Potential at a 300 m Resolution

    Čengić, Mirza / Steinmann, Zoran J.N. / Defourny, Pierre / Doelman, Jonathan C. / Lamarche, Céline / Stehfest, Elke / Schipper, Aafke M. / Huijbregts, Mark A.J.

    Land

    2023  Volume 12, Issue 3

    Abstract: The global expansion of agricultural land is a leading driver of climate change and biodiversity loss. However, the spatial resolution of current global land change models is relatively coarse, which limits environmental impact assessments. To address ... ...

    Abstract The global expansion of agricultural land is a leading driver of climate change and biodiversity loss. However, the spatial resolution of current global land change models is relatively coarse, which limits environmental impact assessments. To address this issue, we developed global maps representing the potential for conversion into agricultural land at a resolution of 10 arc-seconds (approximately 300 m at the equator). We created the maps using artificial neural network (ANN) models relating locations of recent past conversions (2007–2020) into one of three cropland categories (cropland only, mosaics with >50% crops, and mosaics with <50% crops) to various predictor variables reflecting topography, climate, soil, and accessibility. Cross-validation of the models indicated good performance with area under the curve (AUC) values of 0.88–0.93. Hindcasting of the models from 1992 to 2006 revealed a similar high performance (AUC of 0.83–0.91), indicating that our maps provide representative estimates of current agricultural conversion potential provided that the drivers underlying agricultural expansion patterns remain the same. Our maps can be used to downscale projections of global land change models to more fine-grained patterns of future agricultural expansion, which is an asset for global environmental assessments.
    Keywords GLOBIO ; agriculture ; biodiversity ; cropland ; deforestation ; integrated assessment models ; land-cover change ; sustainability
    Language English
    Publishing country nl
    Document type Article ; Online
    ZDB-ID 2682955-1
    ISSN 2073-445X
    ISSN 2073-445X
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

    More links

    Kategorien

To top