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David C. Nielsen - One of the best experts on this subject based on the ideXlab platform.
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water deficit effects on Root Distribution of soybean field pea and chickpea
Field Crops Research, 2006Co-Authors: Joseph G. Benjamin, David C. NielsenAbstract:CroppingdiversityinthecentralGreatPlainsoftheUnitedStatescouldbeincreasedbyincludingsuitable legumesincroprotations.Water islimiting to all crops grown in this region and agronomic crops frequently experiencewater deficit stress during their life cycle.The ability of a plant to change its Root Distribution to exploit deeper stored soil water may be an important mechanism to avoid drought stress. An experiment was conducted to examine legume Root system response to water deficit stress. Chickpea (Cicer arietinum L.), field pea (Pisum sativum L.), and soybean (Glycine max L. Merr.) were grown at two water regimes: under natural rainfall conditions and irrigated to minimizewaterdeficit stress.RootDistributionsforeach specieswere measuredat0.23 mdepthintervalsto adepthof1.12 mdirectlybeneath the plants at the late bloom and mid pod fill growth stages. Roots were washed free of soil and were separated from soil debris by hand. Root surface area measurements were made and Root weights were recorded for each depth interval. Water deficit did not affect the relative soybean Root Distribution. Approximately 97% of the total soybean Roots were in the surface 0.23 m at both sampling times and under both water regimes. In contrast, water deficit stress resulted in a greater proportion of chickpea and field pea Roots to grow deeper in the soil. Under irrigated conditions, about 80% of the chickpea and field pea Roots were in the surface 0.23 m. Under dry conditions, about 66% of the total chickpea and field pea Roots were in the surface 0.23 m and the remainder of the Roots was deeper in the soil profile. Field pea had a Root surface area to weight ratio (AWR) of 35‐40 m 2 kg 1 , chickpea had a AWR of 40‐80 m 2 kg 1 , whereas soybean had a AWR of 3‐7 m 2 kg 1 , depending on plant growth stage. The greater AWR indicates a finer Root system for the field pea and chickpea compared with soybean. From a Rooting perspective, chickpea may be the best suited of these species for dryland crop production in semi-arid climates due to an adaptive Root Distribution based on water availability and large Root surface area per unit Root weight. Published by Elsevier B.V.
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water deficit effects on Root Distribution of soybean field pea and chickpea
Field Crops Research, 2006Co-Authors: Joseph G. Benjamin, David C. NielsenAbstract:Abstract Cropping diversity in the central Great Plains of the United States could be increased by including suitable legumes in crop rotations. Water is limiting to all crops grown in this region and agronomic crops frequently experience water deficit stress during their life cycle. The ability of a plant to change its Root Distribution to exploit deeper stored soil water may be an important mechanism to avoid drought stress. An experiment was conducted to examine legume Root system response to water deficit stress. Chickpea (Cicer arietinum L.), field pea (Pisum sativum L.), and soybean (Glycine max L. Merr.) were grown at two water regimes: under natural rainfall conditions and irrigated to minimize water deficit stress. Root Distributions for each species were measured at 0.23 m depth intervals to a depth of 1.12 m directly beneath the plants at the late bloom and mid pod fill growth stages. Roots were washed free of soil and were separated from soil debris by hand. Root surface area measurements were made and Root weights were recorded for each depth interval. Water deficit did not affect the relative soybean Root Distribution. Approximately 97% of the total soybean Roots were in the surface 0.23 m at both sampling times and under both water regimes. In contrast, water deficit stress resulted in a greater proportion of chickpea and field pea Roots to grow deeper in the soil. Under irrigated conditions, about 80% of the chickpea and field pea Roots were in the surface 0.23 m. Under dry conditions, about 66% of the total chickpea and field pea Roots were in the surface 0.23 m and the remainder of the Roots was deeper in the soil profile. Field pea had a Root surface area to weight ratio (AWR) of 35–40 m2 kg−1, chickpea had a AWR of 40–80 m2 kg−1, whereas soybean had a AWR of 3–7 m2 kg−1, depending on plant growth stage. The greater AWR indicates a finer Root system for the field pea and chickpea compared with soybean. From a Rooting perspective, chickpea may be the best suited of these species for dryland crop production in semi-arid climates due to an adaptive Root Distribution based on water availability and large Root surface area per unit Root weight.
Joseph G. Benjamin - One of the best experts on this subject based on the ideXlab platform.
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water deficit effects on Root Distribution of soybean field pea and chickpea
Field Crops Research, 2006Co-Authors: Joseph G. Benjamin, David C. NielsenAbstract:CroppingdiversityinthecentralGreatPlainsoftheUnitedStatescouldbeincreasedbyincludingsuitable legumesincroprotations.Water islimiting to all crops grown in this region and agronomic crops frequently experiencewater deficit stress during their life cycle.The ability of a plant to change its Root Distribution to exploit deeper stored soil water may be an important mechanism to avoid drought stress. An experiment was conducted to examine legume Root system response to water deficit stress. Chickpea (Cicer arietinum L.), field pea (Pisum sativum L.), and soybean (Glycine max L. Merr.) were grown at two water regimes: under natural rainfall conditions and irrigated to minimizewaterdeficit stress.RootDistributionsforeach specieswere measuredat0.23 mdepthintervalsto adepthof1.12 mdirectlybeneath the plants at the late bloom and mid pod fill growth stages. Roots were washed free of soil and were separated from soil debris by hand. Root surface area measurements were made and Root weights were recorded for each depth interval. Water deficit did not affect the relative soybean Root Distribution. Approximately 97% of the total soybean Roots were in the surface 0.23 m at both sampling times and under both water regimes. In contrast, water deficit stress resulted in a greater proportion of chickpea and field pea Roots to grow deeper in the soil. Under irrigated conditions, about 80% of the chickpea and field pea Roots were in the surface 0.23 m. Under dry conditions, about 66% of the total chickpea and field pea Roots were in the surface 0.23 m and the remainder of the Roots was deeper in the soil profile. Field pea had a Root surface area to weight ratio (AWR) of 35‐40 m 2 kg 1 , chickpea had a AWR of 40‐80 m 2 kg 1 , whereas soybean had a AWR of 3‐7 m 2 kg 1 , depending on plant growth stage. The greater AWR indicates a finer Root system for the field pea and chickpea compared with soybean. From a Rooting perspective, chickpea may be the best suited of these species for dryland crop production in semi-arid climates due to an adaptive Root Distribution based on water availability and large Root surface area per unit Root weight. Published by Elsevier B.V.
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water deficit effects on Root Distribution of soybean field pea and chickpea
Field Crops Research, 2006Co-Authors: Joseph G. Benjamin, David C. NielsenAbstract:Abstract Cropping diversity in the central Great Plains of the United States could be increased by including suitable legumes in crop rotations. Water is limiting to all crops grown in this region and agronomic crops frequently experience water deficit stress during their life cycle. The ability of a plant to change its Root Distribution to exploit deeper stored soil water may be an important mechanism to avoid drought stress. An experiment was conducted to examine legume Root system response to water deficit stress. Chickpea (Cicer arietinum L.), field pea (Pisum sativum L.), and soybean (Glycine max L. Merr.) were grown at two water regimes: under natural rainfall conditions and irrigated to minimize water deficit stress. Root Distributions for each species were measured at 0.23 m depth intervals to a depth of 1.12 m directly beneath the plants at the late bloom and mid pod fill growth stages. Roots were washed free of soil and were separated from soil debris by hand. Root surface area measurements were made and Root weights were recorded for each depth interval. Water deficit did not affect the relative soybean Root Distribution. Approximately 97% of the total soybean Roots were in the surface 0.23 m at both sampling times and under both water regimes. In contrast, water deficit stress resulted in a greater proportion of chickpea and field pea Roots to grow deeper in the soil. Under irrigated conditions, about 80% of the chickpea and field pea Roots were in the surface 0.23 m. Under dry conditions, about 66% of the total chickpea and field pea Roots were in the surface 0.23 m and the remainder of the Roots was deeper in the soil profile. Field pea had a Root surface area to weight ratio (AWR) of 35–40 m2 kg−1, chickpea had a AWR of 40–80 m2 kg−1, whereas soybean had a AWR of 3–7 m2 kg−1, depending on plant growth stage. The greater AWR indicates a finer Root system for the field pea and chickpea compared with soybean. From a Rooting perspective, chickpea may be the best suited of these species for dryland crop production in semi-arid climates due to an adaptive Root Distribution based on water availability and large Root surface area per unit Root weight.
Xubin Zeng - One of the best experts on this subject based on the ideXlab platform.
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Impact of observed vegetation Root Distribution on seasonal global simulations of land surface processes
Journal of Geophysical Research, 2004Co-Authors: Michael Barlage, Xubin ZengAbstract:[1] Using a global Root Distribution derived from observations, results from June to August ensemble simulations are presented. The new Root Distribution shifts the location of Roots in the soil in most regions of the world. Root relocation depends on land use type with some Roots located shallower (e.g., grasslands) and others deeper (e.g., tropical forests). Comparison of the boreal summer results of 1988 and 1993 for a control simulation and simulation with the new Root Distribution produces, in several regions of the world, statistically significant differences of up to 40 W/m2 in the components of the surface energy budget. Analysis of the eastern and western United States shows statistically significant changes of over 1 K in surface air temperature and over 25 W/m2 in surface energy components for both seasonal averages and diurnal cycles. Comparison with observations shows that the new Root Distribution improves the surface air temperature simulation, especially in 1993, but any precipitation improvement is statistically insignificant.
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Global Vegetation Root Distribution for Land Modeling
Journal of Hydrometeorology, 2001Co-Authors: Xubin ZengAbstract:Abstract Vegetation Root Distribution is one of the factors that determine the overall water holding capacity of the land surface and the relative rates of water extraction from different soil layers for vegetation transpiration. Despite its importance, significantly different Root Distributions are used by different land surface models. Using a comprehensive global field survey dataset, vegetation Root Distribution (including Rooting depth) has been developed here for three of the most widely used land cover classifications [i.e., the Biosphere–Atmosphere Transfer Scheme (BATS), International Geosphere–Biosphere Program (IGBP), and version 2 of the Simple Biosphere Model (SiB2)] for direct use by any land model with any number of soil layers.
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The role of Root Distribution for climate simulation over land
Geophysical Research Letters, 1998Co-Authors: Xubin Zeng, Yongjiu Dai, Robert E. Dickinson, Muhammad ShaikhAbstract:A comprehensive global Root database is used to derive vertical Root Distribution and Rooting depth for various vegetation categories in one of the most widely-used land models; i.e., the Biosphere—Atmosphere Transfer Scheme (BATS). Using a variety of observational datasets, observed Root Distribution is found to significantly improves the offline simulation of surface water and energy balance. Global climate modeling further demonstrates that observed Root Distribution primarily affects latent heat flux and soil wetness over tropical and midlatitude land, respectively.
Yonghong Xie - One of the best experts on this subject based on the ideXlab platform.
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Growth and Root Distribution of Vallisneria natans in heterogeneous sediment environments
Aquatic Botany, 2007Co-Authors: Yonghong Xie, Wei Deng, Jinda WangAbstract:Plant growth, biomass allocation and Root Distribution were investigated in the submerged macrophyte Vallisneria natans growing in heterogeneous sediments. Experimentally heterogeneous sediment environments were constructed by randomly placing 4 cm of clay or sandy loam into the top (0-4 cm) or bottom (4-8 cm) layer within an experimental tray, providing two homogeneous and two heterogeneous treatments. Biomass accumulation was significantly affected by the experimental treatments: higher in the homogeneous sediment of clay (32 mg per plant) and the two heterogeneous treatments (about 27 mg per plant), but lower in the homogeneous sediment of sandy loam (15 mg per plant). Root: shoot ratio was also different among the four treatments. Compared with the treatments of clay in the top layer, plants allocated more biomass to Roots at the treatments of sandy loam in the top layer. Heterogeneous sediments significantly affected Root Distribution pattern. Compared with the treatments of sandy loam in the bottom layer, Root number (7-8 versus 13-14) and total Root length (3.6-4.0 cm versus 29.5-40.0 cm) in the bottom layer were significantly higher in the treatments with clay in the bottom layer. These results indicate that both sediment structure and nutrient availability influence growth and Root system Distribution of V natans. (c) 2006 Elsevier B.V. All rights reserved.
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density dependent Root morphology and Root Distribution in the submerged plant vallisneria natans
Environmental and Experimental Botany, 2006Co-Authors: Yonghong Xie, Wenwen WangAbstract:Abstract Root morphology, Root Distribution and biomass allocation in relation to plant nutrient concentration were investigated in the submerged macrophyte Vallisneria natans, growing on two types of sediment (clay and a mixture of sandy loam and clay) with three kinds of initial density (290, 650 and 1300 plants m−2). Both initial density and sediment type had significant impacts on biomass accumulation, Root morphology, Root Distribution, and plant N and P concentrations, whereas biomass allocation was affected by sediment type alone, rather than plant density. For the same sediment type, biomass of the individual was highest in 290 plants m−2, intermediate in 650 plants m−2 and lowest in 1300 plants m−2. When initial density increased from 290 to 1300 plants m−2, Root diameter decreased from 0.36 to 0.31 mm in the mixed sediment and from 0.43 to 0.35 mm in clay, but specific Root length increased from 3.3 to 5.9 m g−1 in the mixed sediment and from 3.0 to 4.6 m g−1 in clay. For the plants grown in the mixed sediment, Root Distribution ratio in 4–8 cm depth increased from 3.3 to 30.8% when initial density increased from 290 to 1300 plants m−2. Increase of density led to decreased plant N and P concentrations. It is concluded that plasticity in Root morphology and Root Distribution exists in V. natans as a response to density, and can help to adapt to competitive environments by increasing efficiency of nutrient acquisition.
Rolf Rauber - One of the best experts on this subject based on the ideXlab platform.
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Intercropping effects on Root Distribution of eight novel winter faba bean genotypes mixed with winter wheat
Field Crops Research, 2019Co-Authors: Juliane Streit, Catharina Meinen, Rolf RauberAbstract:Abstract The spatial Root Distribution of plant species is generally altered by intra- and interspecific competition. The assessment of species specific Root Distribution in intercrops was limited so far because of the difficulties to identify Roots on a species level. We investigated horizontal and vertical Root Distribution of eight winter faba bean genotypes (Vicia faba L.) and one winter wheat cultivar (Triticum aestivum L.) grown in sole stands and in 50/50 substitutive row intercrops. Root samples were taken within and between rows with a Root auger down to 60 cm soil depth in May 2015 and May 2016 at a field site in central Germany. We used Fourier transform infrared (FTIR) spectroscopy for Root species identification. Vertical Root Distribution was described by the equation y = 1 - βd according to Gale and Grigal (1987). Horizontal Root Distribution did not differ between bean and wheat and between sole stands and intercrops averaged across the eight bean genotypes: Bean and wheat Root biomass was on average 65% lower between rows than within rows in sole stands and in intercrops. Both species proliferated into the soil space between the rows and into the intercropping partner’s row to a similar extent. Bean developed 36% of its Root biomass in 0–10 cm soil depth, while wheat had 51%. Bean and wheat had shallower Roots within their own row in intercrops (βbean = 0.933; βwheat = 0.858) compared to their own row in sole stands (βbean = 0.945; βwheat = 0.902). In the intercrops both species occupied deeper soil layers within their partner’s row (βbean = 0.947; βwheat = 0.960) compared to their own row (βbean = 0.933; βwheat = 0.858). This change in vertical Root Distribution was more pronounced for wheat than for bean. Bean genotypes grown in sole stands did not differ in their horizontal and vertical Root Distribution. However, there were significant differences between bean genotypes within wheat rows in the intercrops: bean genotype Vf6 had the largest horizontal spread but the most shallow Root growth within the wheat row, while Vf5 showed the lowest horizontal spread and the highest Root fractions in deep soil layers within the wheat row. The alteration of the vertical Root Distribution of both species in intercrops, compared to the sole crops, could lead to a better resource utilization and an intercrop advantage.
