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Progress in the remote sensing of C3 and C4 grass species aboveground biomass over time and space / Cletah Shoko in ISPRS Journal of photogrammetry and remote sensing, vol 120 (october 2016)
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Titre : Progress in the remote sensing of C3 and C4 grass species aboveground biomass over time and space Type de document : Article/Communication Auteurs : Cletah Shoko, Auteur ; Onisimo Mutanga, Auteur ; Timothy Dube, Auteur Année de publication : 2016 Article en page(s) : pp 13 - 24 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes descripteurs IGN] biomasse aérienne
[Termes descripteurs IGN] dioxyde de carbone
[Termes descripteurs IGN] herbe
[Termes descripteurs IGN] sursol
[Termes descripteurs IGN] surveillance écologique
[Termes descripteurs IGN] teneur en carboneRésumé : (Auteur) The remote sensing of grass aboveground biomass (AGB) has gained considerable attention, with substantial research being conducted in the past decades. Of significant importance is their photosynthetic pathways (C3 and C4), which epitomizes a fundamental eco-physiological distinction of grasses functional types. With advances in technology and the availability of remotely sensed data at different spatial, spectral, radiometric and temporal resolutions, coupled with the need for detailed information on vegetation condition, the monitoring of C3 and C4 grasses AGB has received renewed attention, especially in the light of global climate change, biodiversity and, most importantly, food security. This paper provides a detailed survey on the progress of remote sensing application in determining C3 and C4 grass species AGB. Importantly, the importance of species functional type is highlighted in conjunction with the availability and applicability of different remote sensing datasets, with refined resolutions, which provide an opportunity to monitor C3 and C4 grasses AGB. While some progress has been made, this review has revealed the need for further remote sensing studies to model the seasonal (cyclical) variability, as well as long-term AGB changes in C3 and C4 grasses, in the face of climate change and food security. Moreover, the findings of this study have shown the significance of shifting towards the application of advanced statistical models, to further improve C3 and C4 grasses AGB estimation accuracy. Numéro de notice : A2016-794 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern En ligne : http://dx.doi.org/10.1016/j.isprsjprs.2016.08.001 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=82528
in ISPRS Journal of photogrammetry and remote sensing > vol 120 (october 2016) . - pp 13 - 24[article]Exploring life forms for linking orthopteran assemblage and grassland plant community / Rocco Labadessa in Hacquetia, vol 14 n° 1 (June 2015)
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Titre : Exploring life forms for linking orthopteran assemblage and grassland plant community Type de document : Article/Communication Auteurs : Rocco Labadessa, Auteur ; Luigi Forte, Auteur ; Paola Mairota, Auteur Année de publication : 2015 Article en page(s) : pp 33 - 42 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes descripteurs IGN] état de conservation
[Termes descripteurs IGN] herbe
[Termes descripteurs IGN] insecte
[Termes descripteurs IGN] microhabitat
[Termes descripteurs IGN] prairie
[Vedettes matières IGN] Ecologie forestièreRésumé : (auteur) Orthopterans are well known to represent the majority of insect biomass in many grassland ecosystems. However, the verification of a relationship between the traditional descriptors of orthopteran assemblage structure and plant community patterns is not straightforward. We explore the usefulness of the concept of life forms to provide insights on such ecosystem level relationship. For this purpose, thirty sample sites in semi-natural calcareous grasslands were classified according to the relative proportion of dominant herbaceous plant life forms. Orthopteran species were grouped in four categories, based on the Bei-Bienko’s life form categorization. The association among plant communities, orthopteran assemblages and environmental factors was tested by means of canonical correspondence analysis. Orthoptera groups were found to be associated with distinct plant communities, also indicating the effect of vegetation change on orthopteran assemblages. In particular, geobionta species were associated with all the most disturbed plant communities, while chortobionta and thamnobionta seemed to be dependent on better preserved grassland types. Therefore, the use of life forms could help informing on the relationships of orthopteran assemblages with grassland conservation state. Information on such community relationships at the local scale could also assist managers in the interpretation of habitat change maps in terms of biodiversity changes. Numéro de notice : A2015--003 Affiliation des auteurs : non IGN Thématique : BIODIVERSITE/FORET Nature : Article En ligne : http://dx.doi.org/10.1515/hacq-2015-0012 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=80443
in Hacquetia > vol 14 n° 1 (June 2015) . - pp 33 - 42[article]Response of Swiss forests to management and climate change in the last 60 years / Meinrad Küchler in Annals of Forest Science [en ligne], vol 72 n° 3 (May 2015)
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Titre : Response of Swiss forests to management and climate change in the last 60 years Type de document : Article/Communication Auteurs : Meinrad Küchler, Auteur ; Helen Küchler, Auteur ; Angéline Bedolla, Auteur ; et al., Auteur Année de publication : 2015 Article en page(s) : pp 311 - 320 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Végétation
[Termes descripteurs IGN] analyse diachronique
[Termes descripteurs IGN] arbuste
[Termes descripteurs IGN] changement climatique
[Termes descripteurs IGN] espèce végétale
[Termes descripteurs IGN] forêt
[Termes descripteurs IGN] herbe
[Termes descripteurs IGN] inventaire forestier étranger (données)
[Termes descripteurs IGN] plantation forestière
[Termes descripteurs IGN] recensement
[Termes descripteurs IGN] Suisse
[Termes descripteurs IGN] sylviculture
[Termes descripteurs IGN] températureRésumé : (auteur) Context : Forest vegetation is forecasted to shift upslope several hundred metres by 2100 due to climate warming. However, only a small number of detailed assessments in selected regions have confirmed a climate response on the part of forest vegetation.
Aims : This study aimed to analyse the relative contributions of temperature and other factors to range shifts in forest vegetation by comparing old and revisited relevés in Swiss forests.
Methods : In order to investigate such range shifts, we revisited 451 relevé plots in forests in all parts of Switzerland. Collected data comprise two independent samples, one dating from the 1950s (age 60 sample) on 126 plots and the other dating from the 1990s (age 15 sample) on 325 plots. We defined an indicator value for elevation to estimate the upslope and downslope range shifts of forest species. The influence of different site factors on range shifts was assessed by variance partitioning using Landolt’s (2010) averaged species indicator values. Vegetation changes were analysed by balancing both increasing and decreasing frequencies of plant species.
Results : Our findings show significant differences between the two survey periods, where the averaged species indicator for elevation varied greatly in both the age-60 and the age-15 samples. In addition, a significant upslope shift in the herbaceous forest layer (herbs and tree regeneration) of about 10 m per decade since the mid-twentieth century is evident. Downslope shifts were detected in the shrub/tree layer at lower elevations, which may be explained by factors other than climate warming.
Conclusions : To date, the impact of global warming on tree species composition in Swiss forests has been weaker in comparison to the effects arising from forest management and land use change. Understorey vegetation, however, shows a strong signal of upslope shift that may be explained most adequately by a combination of climate change and other factors.Numéro de notice : 2015-453 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article DOI : 10.1007/s13595-014-0409-x date de publication en ligne : 29/07/2014 En ligne : https://doi.org/10.1007/s13595-014-0409-x Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=77109
in Annals of Forest Science [en ligne] > vol 72 n° 3 (May 2015) . - pp 311 - 320[article]Non-linear partial least square regression increases the estimation accuracy of grass nitrogen and phosphorus using in situ hyperspectral and environmental data / Abel Ramoelo in ISPRS Journal of photogrammetry and remote sensing, vol 82 (August 2013)
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Titre : Non-linear partial least square regression increases the estimation accuracy of grass nitrogen and phosphorus using in situ hyperspectral and environmental data Type de document : Article/Communication Auteurs : Abel Ramoelo, Auteur ; Andrew K. Skidmore, Auteur ; Moses Azong Cho, Auteur ; et al., Auteur Année de publication : 2013 Article en page(s) : pp 27 - 40 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes descripteurs IGN] Afrique du sud (état)
[Termes descripteurs IGN] azote
[Termes descripteurs IGN] données environnementales
[Termes descripteurs IGN] herbe
[Termes descripteurs IGN] image hyperspectrale
[Termes descripteurs IGN] indice de végétation
[Termes descripteurs IGN] parc naturel national
[Termes descripteurs IGN] parcours
[Termes descripteurs IGN] phosphore
[Termes descripteurs IGN] régression non linéaire
[Termes descripteurs IGN] savaneRésumé : (Auteur) Grass nitrogen (N) and phosphorus (P) concentrations are direct indicators of rangeland quality and provide imperative information for sound management of wildlife and livestock. It is challenging to estimate grass N and P concentrations using remote sensing in the savanna ecosystems. These areas are diverse and heterogeneous in soil and plant moisture, soil nutrients, grazing pressures, and human activities. The objective of the study is to test the performance of non-linear partial least squares regression (PLSR) for predicting grass N and P concentrations through integrating in situ hyperspectral remote sensing and environmental variables (climatic, edaphic and topographic). Data were collected along a land use gradient in the greater Kruger National Park region. The data consisted of: (i) in situ-measured hyperspectral spectra, (ii) environmental variables and measured grass N and P concentrations. The hyperspectral variables included published starch, N and protein spectral absorption features, red edge position, narrow-band indices such as simple ratio (SR) and normalized difference vegetation index (NDVI). The results of the non-linear PLSR were compared to those of conventional linear PLSR. Using non-linear PLSR, integrating in situ hyperspectral and environmental variables yielded the highest grass N and P estimation accuracy (R2 = 0.81, root mean square error (RMSE) = 0.08, and R2 = 0.80, RMSE = 0.03, respectively) as compared to using remote sensing variables only, and conventional PLSR. The study demonstrates the importance of an integrated modeling approach for estimating grass quality which is a crucial effort towards effective management and planning of protected and communal savanna ecosystems. Numéro de notice : A2013-409 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=32547
in ISPRS Journal of photogrammetry and remote sensing > vol 82 (August 2013) . - pp 27 - 40[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 081-2013081 RAB Revue Centre de documentation En réserve 3L Disponible Robust hyperspectral vision-based classification for multi-season weed mapping / Y. Zhang in ISPRS Journal of photogrammetry and remote sensing, vol 69 (April 2012)
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Titre : Robust hyperspectral vision-based classification for multi-season weed mapping Type de document : Article/Communication Auteurs : Y. Zhang, Auteur ; D. Slaughter, Auteur ; E. Staab, Auteur Année de publication : 2012 Article en page(s) : pp 65 - 73 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes descripteurs IGN] apprentissage automatique
[Termes descripteurs IGN] Californie (Etats-Unis)
[Termes descripteurs IGN] classification bayesienne
[Termes descripteurs IGN] cultures
[Termes descripteurs IGN] herbe
[Termes descripteurs IGN] identification de plantes
[Termes descripteurs IGN] image hyperspectrale
[Termes descripteurs IGN] photogrammétrie métrologique
[Termes descripteurs IGN] réflectance végétale
[Termes descripteurs IGN] système expert
[Termes descripteurs IGN] variation saisonnièreRésumé : (Auteur) This study investigated the robustness of hyperspectral image-based plant recognition to seasonal variability in a natural farming environment in the context of automated in-row weed control. A machine vision system was developed and equipped with a CCD camera integrated with a line-imaging spectrograph for close-range weed sensing and mapping. Three canonical Bayesian classifiers were developed using canopy reflectance (400–795 nm) collected over three seasons for tomato and weeds. The performance of the three season-specific classifiers was tested by changing environmental conditions, resulting in an increase in total error rate of up to 36%. Global calibration across the complete span of the three seasons produced overall classification accuracies of 85.0%, 90.0% and 92.7%, respectively, for 2005, 2006 and 2008. To improve the stability of global classifier over multiple seasons, a multiclassifier system was constructed with three canonical Bayesian classifiers optimized for the three seasons individually. This system was tested on a data set simulating an upcoming season with field conditions similar to that in 2005. The system increased the total discrimination accuracy to 95.8% for the tested season under simulation. This method provided an innovative direction for achieving robust plant recognition over multiple seasons by integrating expert knowledge from historical data that most closely matched the new field environment. Numéro de notice : A2012-194 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=31641
in ISPRS Journal of photogrammetry and remote sensing > vol 69 (April 2012) . - pp 65 - 73[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 081-2012031 SL Revue Centre de documentation Revues en salle Disponible PermalinkMonitoring herbaceaous fuel moisture content with Spot-Vegetation times-series for fire risk prediction in savanna ecosystems / Jan Verbesselt in Remote sensing of environment, vol 108 n° 4 (29 June 2007)
PermalinkSeparating the weeds from the trees / M. Norris-Rogers in GIM international, vol 21 n° 1 (January 2007)
PermalinkEvaluating temporal variability in the spectral reflectance response of annual ryegrass to changes in nitrogen applications and leaching fractions / M. Baghzouz in International Journal of Remote Sensing IJRS, vol 27 n°18 - 19 - 20 (October 2006)
PermalinkEstimating tropical pasture quality at canopy level using band depth analysis with continuum removal in the visible domain / Onisimo Mutanga in International Journal of Remote Sensing IJRS, vol 26 n° 6 (March 2005)
PermalinkUse of hyperspectral derivative ratios in the red-edge region to identify plant stress responses to gas leaks / K.L. Smith in Remote sensing of environment, vol 92 n° 2 (15/08/2004)
PermalinkIntegrating imaging spectroscopy and neural networks to map grass quality in the Kruger National Park, South Africa / Onisimo Mutanga in Remote sensing of environment, vol 90 n° 1 (15/03/2004)
PermalinkPermalinkUse of vegetation indices to estimate intercepted solar radiation and net carbon dioxide exchange of a grass canopy / D.S. Bartlett in Remote sensing of environment, vol 30 n° 2 (November 1989)
PermalinkC-band scatterometer measurements of a tallgrass prairie / R.D. Martin in Remote sensing of environment, vol 29 n° 3 (01/09/1989)
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