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Biblioteca (s) : |
INIA Treinta y Tres. |
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Fecha : |
12/09/2014 |
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Actualizado : |
27/09/2018 |
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Tipo de producción científica : |
Artículos en Revistas Indexadas Internacionales |
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Autor : |
BAEZA, S.; LEZAMA, F.; PIÑEIRO, G.; ALTESOR, A.; PARUELO, J.M. |
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Afiliación : |
FELIPE LEZAMA HUERTA, Instituto Nacional de Investigación Agropecuaria (INIA), Uruguay. |
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Título : |
Spatial variability of above-ground net primary production in Uruguayan grasslands: A remote sensing approach. |
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Fecha de publicación : |
2010 |
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Fuente / Imprenta : |
Applied Vegetation Science, 2010, v. 13, no. 1 p. 72-85. |
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ISSN : |
1654-109X |
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DOI : |
10.1111/j.1654-109X.2009.01051.x |
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Idioma : |
Inglés |
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Notas : |
Article history: Received 4 November 2008; accepted 16 July 2009. Published in 2010. |
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Contenido : |
Abstract:
Question: How does above-ground net primary production (ANPP) differ (estimated from remotely sensed data) among vegetation units in sub-humid temperate grasslands?
Location: Centre-north Uruguay.
Methods: A vegetation map of the study area was generated from LANDSAT imagery and the landscape configuration described. The functional heterogeneity of mapping units was analysed in terms of the fraction of photosynthetically active radiation absorbed by green vegetation (fPAR), calculated from the normalized difference vegetation index (NDVI) images provided by the moderate resolution imaging spectroradiometer (MODIS) sensor. Finally, the ANPP of each grassland class was estimated using NDVI and climatic data.
Results: Supervised classification presented a good overall accuracy and moderate to good average accuracy for grassland classes. Meso-xerophytic grasslands
occupied 45% of the area, Meso-hydrophytic grasslands 43% and Lithophytic steppes 6%. The landscape was shaped by a matrix of large, unfragmented patches of Meso-xerophytic and Meso-hydrophytic grasslands. The region presented the lowest anthropic fragmentation degree reported for the Rio de la Plata grasslands. All grassland units showed bimodal annual fPAR seasonality, with spring and autumn peaks. Meso-hydrophytic grasslands showed a radiation interception 10% higher than the other units. On an annual basis, Meso-hydrophytic grasslands produced 3800 kg dry matter (DM) ha 1 yr 1 and Meso-xerophytic grasslands and ithophytic
steppes around 3400 kg DM ha 1 yr 1 . Mesoxerophytic grasslands had the largest spatial variation during most of the year. The ANPP temporal variation was higher than the fPAR variability.
Conclusions: Our results provide valuable information for grazing management (identifying spatial and temporal variations of ANPP) and grassland conservation (identifying the spatial distribution of vegetation units). MenosAbstract:
Question: How does above-ground net primary production (ANPP) differ (estimated from remotely sensed data) among vegetation units in sub-humid temperate grasslands?
Location: Centre-north Uruguay.
Methods: A vegetation map of the study area was generated from LANDSAT imagery and the landscape configuration described. The functional heterogeneity of mapping units was analysed in terms of the fraction of photosynthetically active radiation absorbed by green vegetation (fPAR), calculated from the normalized difference vegetation index (NDVI) images provided by the moderate resolution imaging spectroradiometer (MODIS) sensor. Finally, the ANPP of each grassland class was estimated using NDVI and climatic data.
Results: Supervised classification presented a good overall accuracy and moderate to good average accuracy for grassland classes. Meso-xerophytic grasslands
occupied 45% of the area, Meso-hydrophytic grasslands 43% and Lithophytic steppes 6%. The landscape was shaped by a matrix of large, unfragmented patches of Meso-xerophytic and Meso-hydrophytic grasslands. The region presented the lowest anthropic fragmentation degree reported for the Rio de la Plata grasslands. All grassland units showed bimodal annual fPAR seasonality, with spring and autumn peaks. Meso-hydrophytic grasslands showed a radiation interception 10% higher than the other units. On an annual basis, Meso-hydrophytic grasslands produced 3800 kg dry matter (DM) ha 1 yr 1 and Meso-xerophytic grassl... Presentar Todo |
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Palabras claves : |
LAND-COVE CLASSIFICATION; NATIVE GRASS-LANDS; NDVI; NORMALIZED DIFFERENCE VETETATION INDEX (NDVI); RADIATION-USE EFFICIENCY; RIO DE LA PLATA GRASSLANDS. |
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Thesagro : |
ESPECIES; IDENTIFICACION; PASTIZAL NATURAL; SISTEMAS GEOGRAFICOS; URUGUAY. |
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Asunto categoría : |
F70 Taxonomía y geografía de las plantas |
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Marc : |
LEADER 03025naa a2200337 a 4500
001 1050200
005 2018-09-27
008 2010 bl uuuu u00u1 u #d
022 $a1654-109X
024 7 $a10.1111/j.1654-109X.2009.01051.x$2DOI
100 1 $aBAEZA, S.
245 $aSpatial variability of above-ground net primary production in Uruguayan grasslands$bA remote sensing approach.$h[electronic resource]
260 $c2010
500 $aArticle history: Received 4 November 2008; accepted 16 July 2009. Published in 2010.
520 $aAbstract: Question: How does above-ground net primary production (ANPP) differ (estimated from remotely sensed data) among vegetation units in sub-humid temperate grasslands? Location: Centre-north Uruguay. Methods: A vegetation map of the study area was generated from LANDSAT imagery and the landscape configuration described. The functional heterogeneity of mapping units was analysed in terms of the fraction of photosynthetically active radiation absorbed by green vegetation (fPAR), calculated from the normalized difference vegetation index (NDVI) images provided by the moderate resolution imaging spectroradiometer (MODIS) sensor. Finally, the ANPP of each grassland class was estimated using NDVI and climatic data. Results: Supervised classification presented a good overall accuracy and moderate to good average accuracy for grassland classes. Meso-xerophytic grasslands occupied 45% of the area, Meso-hydrophytic grasslands 43% and Lithophytic steppes 6%. The landscape was shaped by a matrix of large, unfragmented patches of Meso-xerophytic and Meso-hydrophytic grasslands. The region presented the lowest anthropic fragmentation degree reported for the Rio de la Plata grasslands. All grassland units showed bimodal annual fPAR seasonality, with spring and autumn peaks. Meso-hydrophytic grasslands showed a radiation interception 10% higher than the other units. On an annual basis, Meso-hydrophytic grasslands produced 3800 kg dry matter (DM) ha 1 yr 1 and Meso-xerophytic grasslands and ithophytic steppes around 3400 kg DM ha 1 yr 1 . Mesoxerophytic grasslands had the largest spatial variation during most of the year. The ANPP temporal variation was higher than the fPAR variability. Conclusions: Our results provide valuable information for grazing management (identifying spatial and temporal variations of ANPP) and grassland conservation (identifying the spatial distribution of vegetation units).
650 $aESPECIES
650 $aIDENTIFICACION
650 $aPASTIZAL NATURAL
650 $aSISTEMAS GEOGRAFICOS
650 $aURUGUAY
653 $aLAND-COVE CLASSIFICATION
653 $aNATIVE GRASS-LANDS
653 $aNDVI
653 $aNORMALIZED DIFFERENCE VETETATION INDEX (NDVI)
653 $aRADIATION-USE EFFICIENCY
653 $aRIO DE LA PLATA GRASSLANDS
700 1 $aLEZAMA, F.
700 1 $aPIÑEIRO, G.
700 1 $aALTESOR, A.
700 1 $aPARUELO, J.M.
773 $tApplied Vegetation Science, 2010$gv. 13, no. 1 p. 72-85.
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Registro original : |
INIA Treinta y Tres (TT) |
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Registro completo
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Biblioteca (s) : |
INIA Treinta y Tres. |
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Fecha actual : |
18/04/2022 |
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Actualizado : |
18/04/2022 |
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Tipo de producción científica : |
Artículos en Revistas Indexadas Internacionales |
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Circulación / Nivel : |
Internacional - -- |
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Autor : |
LEZAMA, F.; PARUELO, J. |
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Afiliación : |
FELIPE LEZAMA, Department of Environmental Systems, Faculty of Agronomy, University of República, Montevideo, Uruguay.; JOSÉ PARUELO, Institute of Ecology and Environmental Sciences, Faculty of Sciences, UDELAR, UY. Department of Quantitative Methods and Information Systems, FAGRO, UY. INIA (Instituto Nacional de Investigación Agropecuaria), Uruguay. |
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Título : |
Regional assessment of stocking rate effects on uruguayan rangelands: a ranch-level study. |
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Fecha de publicación : |
2022 |
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Fuente / Imprenta : |
Rangeland Ecology & Management, 2022, volume 82, pages 58-65. Doi: https://doi.org/10.1016/j.rama.2022.02.005 |
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DOI : |
10.1016/j.rama.2022.02.005 |
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Idioma : |
Inglés |
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Notas : |
Article history: Received 27 April 2021 // Revised 9 February 2022 // Accepted 16 February 2022. |
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Contenido : |
We analyzed the variation of plant composition, forage production, and livestock diet across a broad stocking rate gradient on Eastern Hills rangelands of Uruguay. Our approach encompassed five ranches subjected to mixed sheep-cattle grazing and combined field surveys, microhistological fecal analysis, and remote sensing techniques. We hypothesized that selectivity would decrease as stocking rate increased. Vegetation data and fecal samples were obtained in 17 paddocks in 2008. To investigate the role of stocking rate on vegetation, we focused on dominant species and forage type cover. Diet composition was analyzed at forage type level. Annual net primary productivity was estimated for each paddock using the normalized difference vegetation index derived from the MODIS (Moderate Resolution Imaging Spectroradiometer) sensor. We found a clear relationship between the variation in stocking rate and floristic and forage type composition, both suggesting a deterioration of grassland conservation status. Cool season grass cover varied from 25% to 5%, from low to high stocking rates. Dicot cover showed an opposite trend, with values around 15% in the low and moderate stocking levels and reaching 35% on high-stocked paddocks. Diet composition and diet overlap between herbivores also showed clear patterns of response to stocking rate. On the other hand, livestock selectivity interacted with herbivore type. While cattle showed the expected pattern, sheep did not decrease selectivity in winter as stocking rate increased. Contrary to expectations, annual net primary productivity was similar across the different stocking rate levels and the month of maximum productivity was generally March. Our study provides strong evidence of marked rangeland degradation; however, the lack of response in terms of ANPP and the ability of sheep to maintain selectivity under high stocking rates could help to explain the lack of responsiveness in the adoption of generalized stocking adjustments by the ranchers. MenosWe analyzed the variation of plant composition, forage production, and livestock diet across a broad stocking rate gradient on Eastern Hills rangelands of Uruguay. Our approach encompassed five ranches subjected to mixed sheep-cattle grazing and combined field surveys, microhistological fecal analysis, and remote sensing techniques. We hypothesized that selectivity would decrease as stocking rate increased. Vegetation data and fecal samples were obtained in 17 paddocks in 2008. To investigate the role of stocking rate on vegetation, we focused on dominant species and forage type cover. Diet composition was analyzed at forage type level. Annual net primary productivity was estimated for each paddock using the normalized difference vegetation index derived from the MODIS (Moderate Resolution Imaging Spectroradiometer) sensor. We found a clear relationship between the variation in stocking rate and floristic and forage type composition, both suggesting a deterioration of grassland conservation status. Cool season grass cover varied from 25% to 5%, from low to high stocking rates. Dicot cover showed an opposite trend, with values around 15% in the low and moderate stocking levels and reaching 35% on high-stocked paddocks. Diet composition and diet overlap between herbivores also showed clear patterns of response to stocking rate. On the other hand, livestock selectivity interacted with herbivore type. While cattle showed the expected pattern, sheep did not decrease selectivity i... Presentar Todo |
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Palabras claves : |
(NDVI); EASTERN HILLS; FORAGE TYPES; LIVESTOCK DIET; MICROHISTOLOGICAL TECHNIQUE; NORMALIZED DIFFERENCE VEGETATION INDEX; PLANT COMPOSITION. |
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Asunto categoría : |
F40 Ecología vegetal |
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Marc : |
LEADER 02892naa a2200241 a 4500
001 1063033
005 2022-04-18
008 2022 bl uuuu u00u1 u #d
024 7 $a10.1016/j.rama.2022.02.005$2DOI
100 1 $aLEZAMA, F.
245 $aRegional assessment of stocking rate effects on uruguayan rangelands$ba ranch-level study.$h[electronic resource]
260 $c2022
500 $aArticle history: Received 27 April 2021 // Revised 9 February 2022 // Accepted 16 February 2022.
520 $aWe analyzed the variation of plant composition, forage production, and livestock diet across a broad stocking rate gradient on Eastern Hills rangelands of Uruguay. Our approach encompassed five ranches subjected to mixed sheep-cattle grazing and combined field surveys, microhistological fecal analysis, and remote sensing techniques. We hypothesized that selectivity would decrease as stocking rate increased. Vegetation data and fecal samples were obtained in 17 paddocks in 2008. To investigate the role of stocking rate on vegetation, we focused on dominant species and forage type cover. Diet composition was analyzed at forage type level. Annual net primary productivity was estimated for each paddock using the normalized difference vegetation index derived from the MODIS (Moderate Resolution Imaging Spectroradiometer) sensor. We found a clear relationship between the variation in stocking rate and floristic and forage type composition, both suggesting a deterioration of grassland conservation status. Cool season grass cover varied from 25% to 5%, from low to high stocking rates. Dicot cover showed an opposite trend, with values around 15% in the low and moderate stocking levels and reaching 35% on high-stocked paddocks. Diet composition and diet overlap between herbivores also showed clear patterns of response to stocking rate. On the other hand, livestock selectivity interacted with herbivore type. While cattle showed the expected pattern, sheep did not decrease selectivity in winter as stocking rate increased. Contrary to expectations, annual net primary productivity was similar across the different stocking rate levels and the month of maximum productivity was generally March. Our study provides strong evidence of marked rangeland degradation; however, the lack of response in terms of ANPP and the ability of sheep to maintain selectivity under high stocking rates could help to explain the lack of responsiveness in the adoption of generalized stocking adjustments by the ranchers.
653 $a(NDVI)
653 $aEASTERN HILLS
653 $aFORAGE TYPES
653 $aLIVESTOCK DIET
653 $aMICROHISTOLOGICAL TECHNIQUE
653 $aNORMALIZED DIFFERENCE VEGETATION INDEX
653 $aPLANT COMPOSITION
700 1 $aPARUELO, J.
773 $tRangeland Ecology & Management, 2022, volume 82, pages 58-65. Doi: https://doi.org/10.1016/j.rama.2022.02.005
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