Registro Completo |
Biblioteca(s): |
Embrapa Pantanal. |
Data corrente: |
01/10/1997 |
Data da última atualização: |
05/04/2017 |
Autoria: |
LEE, C. A.; LAUENROTH, W. K. |
Título: |
Spatial distributions of grass and shrub root systems in the shortgrass steppe. |
Ano de publicação: |
1994 |
Fonte/Imprenta: |
American Midland Naturalist, v.132, n.1, p.117-123, 1994. |
Idioma: |
Inglês |
Conteúdo: |
In water-limited ecosystem such as the shortgrass steppe of North America, the ability of plants to absorb sufficient water for growth and reproduction is dependent upon the characteristics of their root systems. Our objective was to evaluate the spatial distributions of roots of three plant life forms: a grass (Bouteloua gracilis) (H.B.K.) Lag., a dwarf shrub [Gutierrezia sarothrae (Push.) Britt. & Rusby] and a shrub [Atriplex canescens (Pursh.) Nutt.]. Our interests were in a quantitative evaluation of evidence that different life forms obtained water from different soil layers. Root systems were excavated and evaluated in terms of horizontal and vertical extension, and proportion of total root lenght in each 10-cm layer of the soil profile. Bouteloua gracilis had over 80% of its roots in the top 50 cm of the soil, whereas the depth at which Atriplex canescens had over 80% of its roots was 100 cm. The corresponding depth for Gutierrezia sarothrae was 80 cm. Both of the woody plants had deeper and more widely spreading root systems than the grass. The environment of the shortgrass steppe is characterized by low and variable water availability. These conditions lead to a contribution of available water that is biased toward the upper soil layers. The greater concentration of roots of Bouteloua gracilis in the soil layers near the surface compared to the two woody species provides a potential explanation for its dominance in the shortgrass steppe. |
Palavras-Chave: |
Distribuicao; Distribution; Growth; Plant; Shrub root system. |
Thesagro: |
Crescimento; Planta. |
Categoria do assunto: |
-- |
Marc: |
LEADER 02048naa a2200217 a 4500 001 1791830 005 2017-04-05 008 1994 bl --- 0-- u #d 100 1 $aLEE, C. A. 245 $aSpatial distributions of grass and shrub root systems in the shortgrass steppe. 260 $c1994 520 $aIn water-limited ecosystem such as the shortgrass steppe of North America, the ability of plants to absorb sufficient water for growth and reproduction is dependent upon the characteristics of their root systems. Our objective was to evaluate the spatial distributions of roots of three plant life forms: a grass (Bouteloua gracilis) (H.B.K.) Lag., a dwarf shrub [Gutierrezia sarothrae (Push.) Britt. & Rusby] and a shrub [Atriplex canescens (Pursh.) Nutt.]. Our interests were in a quantitative evaluation of evidence that different life forms obtained water from different soil layers. Root systems were excavated and evaluated in terms of horizontal and vertical extension, and proportion of total root lenght in each 10-cm layer of the soil profile. Bouteloua gracilis had over 80% of its roots in the top 50 cm of the soil, whereas the depth at which Atriplex canescens had over 80% of its roots was 100 cm. The corresponding depth for Gutierrezia sarothrae was 80 cm. Both of the woody plants had deeper and more widely spreading root systems than the grass. The environment of the shortgrass steppe is characterized by low and variable water availability. These conditions lead to a contribution of available water that is biased toward the upper soil layers. The greater concentration of roots of Bouteloua gracilis in the soil layers near the surface compared to the two woody species provides a potential explanation for its dominance in the shortgrass steppe. 650 $aCrescimento 650 $aPlanta 653 $aDistribuicao 653 $aDistribution 653 $aGrowth 653 $aPlant 653 $aShrub root system 700 1 $aLAUENROTH, W. K. 773 $tAmerican Midland Naturalist$gv.132, n.1, p.117-123, 1994.
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Embrapa Pantanal (CPAP) |
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