Academic literature on the topic 'Tree water use'
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Journal articles on the topic "Tree water use"
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Glenn, D. M., J. W. Worthington, W. V. Welker, and M. J. McFarland. "Estimation of Peach Tree Water Use Using Infrared Thermometry." Journal of the American Society for Horticultural Science 114, no. 5 (September 1989): 737–41. http://dx.doi.org/10.21273/jashs.114.5.737.
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Abstract Infrared (IR) thermometry has not been extensively applied in deciduous tree fruit production to determine water use. The objectives of this study were to a) examine IR measurement techniques for evaluating canopy temperatures in peach [Prunus persica (L.) Batsch.] trees; b) evaluate a foliage-minus-air temperature- (Tc – Ta) based diffusion equation for vapor flux used to predict tree water use; and c) measure the Tc – Ta response of irrigated peach trees over a range of air vapor pressure deficits. The mean Tc – Ta for a tree was similar for readings made from the canopy sides (horizontal orientation of the IR thermometer) or canopy tops (vertical orientation). Peach tree water use from weighing lysimeters was predicted within 9.4% ± 3% using the diffusion equation for vapor flux. Tc – Ta for irrigated peach trees was related to the air vapor pressure deficit (VPD). Data are presented to show that stomatal response to VPD does alter the Tc – Ta nonstressed baseline for peach at VPD > 2 kPa.
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Levitt, D. G., J. R. Simpson, and J. L. Tipton. "Water Use of Two Landscape Tree Species in Tucson, Arizona." Journal of the American Society for Horticultural Science 120, no. 3 (May 1995): 409–16. http://dx.doi.org/10.21273/jashs.120.3.409.
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Although water conservation programs in the arid southwestern United States have prompted prudent landscaping practices such as planting low water use trees, there is little data on the actual water use of most species. The purpose of this study was to determine the actual water use of two common landscape tree species in Tucson, Ariz., and water use coefficients for two tree species based on the crop coefficient concept. Water use of oak (Quercus virginiana `Heritage') and mesquite (Prosopis alba `Colorado') trees in containers was measured from July to October 1991 using a precision balance. Water-use coefficients for each tree species were calculated as the ratio of measured water use per total leaf area or per projected canopy area to reference evapotranspiration obtained from a modified FAO Penman equation. After accounting for tree growth, water-use coefficients on a total leaf area basis were 0.5 and 1.0 for oak and mesquite, respectively, and on a projected canopy area basis were 1.4 and 1.6 for oaks and mesquites, respectively. These coefficients indicate that mesquites (normally considered xeric trees) use more water than oaks (normally considered mesic trees) under nonlimiting conditions.
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Kjelgren, Roger. "MODELING WATER USE OF SHADE TREES IN FIELD PRODUCTION NURSERIES." HortScience 31, no. 6 (October 1996): 916C—916. http://dx.doi.org/10.21273/hortsci.31.6.916c.
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Supplemental watering of shade trees in field production nurseries is needed, even in summer-rainfall climates, to achieve maximum growth. Scheduling the timing and amount of supplemental watering makes more efficient use of financial and water resources while maintaining maximum growth. Methods of scheduling supplemental watering based on uniform canopy and rooting in production agriculture must be modified, however, for shade trees in a production setting. Nursery trees are non-uniform in canopy and rooting compared to an agricultural crop. Applying the water budget method can be effective with sprinkler systems if tree water loss and rooting depth can be properly estimated. A measure of reference evapotranspiration and a species-specific multiplier are typically used to estimate water loss. Since species diversity in a field nursery is quite high, however, estimates of both tree transpiration and rooting depth must necessarily be simplified assumptions less accurate than for a uniform agricultural crop. If supplemental water is to be applied with drip irrigation, estimates of tree transpiration and soil water depletion need to be converted to volume units with information on total tree leaf area.
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Steinberg, Susan L., Marshall J. McFarland, and Josiah W. Worthington. "Antitranspirant Reduces Water Use by Peach Trees Following Harvest." Journal of the American Society for Horticultural Science 115, no. 1 (January 1990): 20–24. http://dx.doi.org/10.21273/jashs.115.1.20.
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The potential for reducing water use of peach [Prunus persica (L.) Batsch] trees with antitranspirants following fruit harvest was investigated using matched peach trees planted in an outdoor twin weighing lysimeter facility. A 10% solution of the antitranspirant Wilt Pruf NCF was applied to one of the two trees on 7 July 1986. Immediately after application, water use of the treated tree was reduced by 40%. One month after treatment, the water use was reduced 30% and, by the termination of the experiment (85 days after treatment), water use was reduced 12% as compared to control. The average reduction in tree water use for the entire period was 30%. Fully expanded, sunlit leaves (nodes 10 to 20 from the terminal end) from the treated tree exhibited the greatest reduction in water loss compared with immature or inner canopy, shaded leaves. Use of the antitranspirant did not prevent the development of water stress once a critical level of soil moisture was reached. The change in tree water use induced by the antitranspirant did not significantly reduce shoot length, new leaf production, or individual leaf size on actively growing, current-season branches. Fruit and leaf bud initiation, as measured the following spring, were not affected: however. flower bud maturation could not be evaluated due to freeze damage. Chemical name used: di-1-p-menthene (Wilt Pruf NCF).
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Vrecenak, Arthur J. "SHADE TREE TRANSPIRATION AND WATER USE." Arboricultural Journal 12, no. 1 (February 1988): 77–81. http://dx.doi.org/10.1080/03071375.1988.9756379.
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Fernández, J. E., and F. Moreno. "Water Use by the Olive Tree." Journal of Crop Production 2, no. 2 (September 10, 2000): 101–62. http://dx.doi.org/10.1300/j144v02n02_05.
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Simpson, David G. "Water use of interior Douglas-fir." Canadian Journal of Forest Research 30, no. 4 (April 1, 2000): 534–47. http://dx.doi.org/10.1139/x99-233.
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Water use of individual Douglas-fir (Pseudotsuga menziesii var. glauca (Beissn.) Franco) trees was measured in two plots at a forest site in southern British Columbia, Canada. Average daily early summer water use by trees with diameters of 7.5-70 cm varied from 1.8 to 166 L. Sap flux density (cm3 water/cm2 sapwood per hour) was linearly related to shoot xylem pressure potential and was found to increase with increasing vapour pressure deficit (VPD) and short-wave irradiance (I), reaching maximum rates with VPD > 0.6 kPa and I > 200 W·m-2. Daily sap flux density varied among trees but was not related to tree diameter, so an average value of 1137.4 L·m-2 sapwood area was used to estimate average early summer stand transpiration for the two plots of 1.08 and 1.5 mm·d-1. A close curvilinear relationship (r2 = 0.85) was found between stem cross-sectional area increment and sapwood area. The relationship was only slightly better (r2 = 0.89) between area increment and early summer individual tree water use. Stand volume growth for 1988-1998 for the two plots was 36-47 m3·ha-1. Stem volume relative growth rate over this 10-year period is estimated at 0.027 and 0.029 m3·m-3·a-1.
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Maier, Burley, Cook, Ghezehei, Hazel, and Nichols. "Tree Water Use, Water Use Efficiency, and Carbon Isotope Discrimination in Relation to Growth Potential in Populus deltoides and Hybrids under Field Conditions." Forests 10, no. 11 (November 6, 2019): 993. http://dx.doi.org/10.3390/f10110993.
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We explored the relationship between tree growth, water use, and related hydraulic traits in Populus deltoides Bartr. ex Marsh.and hybrid clones, to examine potential trade-offs between growth and water use efficiency. Nine genotypes, six P. deltoides and three hybrid clones, that represented genotypes with high (Group H), intermediate (Group I), and low (Group L) growth performance were selected for study, based on year-two standing stem biomass in a replicated field trial. In year four, tree growth, transpiration (Et), canopy stomatal conductance (Gs), whole-tree hydraulic conductance (Gp), and carbon isotope discrimination (Δ13C) were measured. Tree sap flux was measured continuously using thermal dissipation probes. We hypothesized that Group H genotypes would have increased growth efficiency (GE), increased water use efficiency of production (WUEp, woody biomass growth/Et), lower Δ13C, and greater Gp than slower growing genotypes. Tree GE increased with relative growth rate (RGR), and mean GE in Group H was significantly greater than L, but not I. Tree WUEp ranged between 1.7 and 3.9 kg biomass m3 H2O−1, which increased with RGR. At similar levels of Et, WUEp was significantly greater in Group H (2.45 ± 0.20 kg m−3), compared to I (2.03 ± 0.18 kg m−3) or L (1.72 ± 0.23 kg m−3). Leaf and wood Δ13C scaled positively with stem biomass growth but was not correlated with WUEp. However, at a similar biomass increment, clones in Group H and I had significantly lower leaf Δ13C than Group L. Similarly, Group H clones had a significantly lower wood Δ13C than Group L, supporting our hypothesis of increased WUE in larger trees. Tree physiological and hydraulic traits partially explain differences in WUEp and Δ13C, and suggest that clone selection and management activities that increase tree biomass production will likely increase tree and stand WUE. However, more research is needed to discern the underlying hydraulic mechanisms responsible for the higher WUE exhibited by large trees and distinct clones.
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Khemira, H., L. E. Schrader, F. J. Peryea, R. Kammereck, and R. Burrows. "Effect of Rootstock on Nitrogen and Water Use in Apple Trees." HortScience 32, no. 3 (June 1997): 486A—486. http://dx.doi.org/10.21273/hortsci.32.3.486a.
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One-year-old `Fuji' apple trees on six rootstocks (Mark, M.9, M.26, M.7A, MM.106, and MM.111) were compared for N and water uptake and utilization. The trees were potted in sand and subjected to a 75-day N-deprivation period (supplied with modified Hoagland's solution lacking N) to deplete their N reserves. Thereafter, they were supplied with a complete modified Hoagland's solution. Uptake of water and N differed by rootstock. Water and N uptake were positively related to tree dry weight (r = +0.97, P = 0.001). Trees that had the highest N concentrations at planting were the last to set bud during the N-deprivation-phase. Tree size after one growing season depended largely on rootstock girth and whole-tree-Nconcentration at planting (r2 = 0.80, P = 0.0001) regardless of rootstock. Water and N uptake efficiency (liter of water or mg N absorbed per g root dry weight, respectively) differed among the rootstocks, being highest for trees on MM.111 and lowest for trees on M.7A rootstock. Nitrogen and water utilization efficiency (g dry weight gained per mg N or per liter of water absorbed, respectively) were not influenced by the rootstock.
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Jones, Benjamin A., and John Fleck. "Urban Trees and Water Use in Arid Climates: Insights from an Integrated Bioeconomic-Health Model." Water Economics and Policy 04, no. 04 (October 2018): 1850022. http://dx.doi.org/10.1142/s2382624x18500224.
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Managing outdoor water use while maintaining urban tree cover is a key challenge for water managers in arid climates. Urban trees generate flows of ecosystem services in arid areas, but also require significant amounts of irrigation. In this paper, a bioeconomic-health model of trees and water use is developed to investigate management of an urban forest canopy when irrigation is costly, water has economic value, and trees provide ecosystem services. The optimal tree irrigation decision is illustrated for Albuquerque, New Mexico, an arid Southwest US city. Using a range of monetary values for water, we find that the tree irrigation decision is sensitive to the value selected. Urban deforestation is optimal when the value of water is sufficiently high, or alternatively starts low, but grows to cross a specific threshold. If, however, the value of water is sufficiently low or if the value of tree cover rises over time, then deforestation is not optimal. The threshold value of water where the switch is made between zero and partial deforestation is well within previously identified ranges on actual water values. This model can be applied generally to study the tradeoffs between urban trees and water use in arid environments.
Dissertations / Theses on the topic "Tree water use"
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Zhang, Heping. "Water use in a poplar tree-pasture system." Thesis, University of Reading, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.336665.
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Hentschel, Rainer. "Water use – from leaf to tree to stand level." Doctoral thesis, Humboldt-Universität zu Berlin, Lebenswissenschaftliche Fakultät, 2016. http://dx.doi.org/10.18452/17497.
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Im Fokus dieser Arbeit steht die physiologische Reaktion von Einzelbäumen gegenüber Trockenheit. Das angewandte hydrodynamische Xylemwasserfluss (XWF) Model liefert eine hydrologische Abbildung der Einzelbäume. Aufgrund des funktionalen Zusammenhanges zwischen dem Blattwasserpotential und der stomatären Leitfähigkeit erlaubt das XWF Modell eine öko-physiologische Simulation der stomatären Reaktion auf Blattebene. Hieraus ergeben sich auch Rückschlüsse auf die Assimilationsleistung. Als integratives Maß des Verhältnisses zwischen der Kohlenstoffaufnahme und dem Wasserverbrauch werden die stabilen (Jahrring-) Isotope des Kohlen- und des Sauerstoffs analysiert. Des Weiteren werden Messungen des jährlichen Dickenwachstums sowie des Tagesganges der Xylem-Saftflussdichte untersucht. Die XWF Simulationen zeigen eine gute Übereinstimmung mit den Saftflussdichtemessungen an Buchen (Fagus sylvatica L.). Eine effektive stomatäre Regulation der Transpiration während der extreme Trockenheit des Jahres 2003 schütze die untersuchten Buchen vor einer Fehlfunktion des Wassertransportes. Gleichfalls konnte das Wachstum aufrechterhalten werden, was eine Remobilisierung von gespeichertem Kohlenstoff während Zeiten eingeschränkten Gasaustausches nahe legt. Des Weiteren zeigte sich Unterschiede in den (Wasser-) Nutzungsstrategien von Fichten (Picea abies L. Karst.), was auf eine physiologische Prädisposition der Gefährdung einzelner Bäume gegenüber Trockenstress hinweist. Die gemeinsame Betrachtung von hydrodynamischen Simulationen und öko-physiologischen Messungen kann dazu beitragen die komplexen physiologischen Prozesse auf Blattebene abzubilden und diese auf Baumebene zu projizieren. Weiterführend können somit die Vorhersagen des Wasserhaushaltes auf Bestandesebene angepasst und Auswirkungen des Klimawandels besser abgeschätzt werden.This study focuses on the physiological response of individual trees towards drought. The hydrodynamic model of xylem water flow (XWF) applied provides a hydraulic map of the individual trees. Due to the functional linkage between the leaf water status and the stomatal conductance, the XWF model enables an eco-physiological representation of the stomatal response at the leaf level. As an integrative record of the ratio between water loss and carbon gain, the tree ring carbon and oxygen stable isotopes have been analyzed. Furthermore, measurements of seasonal growth and diurnal sap flow densities include in my study. The hydrodynamic XWF simulation shows good agreement with sap flow density measurements of beech trees (Fagus sylvatica L.). It demonstrates that the study trees were able to cope with the extreme drought events of the years 2003 due to a strong limitation of water loss by stomatal closure. The assessment of growth data and stable isotope measurements suggest an increased remobilization of stored carbohydrates during periods of limited gas exchange. Furthermore, differences in the resource use strategies of Norway spruce trees (Picea abies L. Karst.) suggest a physiological predisposition of individual trees toward drought stress. The combined investigation of hydrodynamic modeling and eco-physiological approaches helps to bridge the gap between the detailed examinations of physiological processes at the leaf level to the forecast of water use at the tree level. Thus, predictions of the water balance at the stand level may be adjusted for a better representation of the impact of climate change.
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Levitt, Daniel Glenn. "Water use of two desert landscape tree species in Tucson, Arizona." Diss., The University of Arizona, 1992. http://hdl.handle.net/10150/185911.
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Although water conservation programs in the arid Southwest have prompted prudent landscaping practices such as planting low water use trees, there is little data on the actual water use of most species. Few methods or models have been developed for measuring tree water use. The stem heat balance method is one such method. Predictive models of tree water use have been limited to applications of the Penman-Monteith (PM) equation with varying degrees of success. The purpose of this study was: to validate stem flow gauge accuracy in a greenhouse and a desert environment; to determine the actual water use of two landscape tree species in Tucson, Arizona; to determine water use coefficients for two tree species based on the crop coefficient concept; and to test and develop a predictive model of tree water use based on the Penman-Monteith equation. Water use of oak (Quercus virginiana 'Heritage') and mesquite (Prosopis alba 'Colorado') trees in containers was measured using a precision balance and stem flow gauges. Water use coefficients for each tree species were calculated as the ratio of water use per total leaf area and per projected canopy area to reference evapotranspiration (ETo) using the Penman combination equation. After accounting for tree growth, water use coefficients on a total leaf area basis were calculated to be 0.48 and 0.97 for the oaks and mesquites, respectively, and 1.36 and 1.56 for the oaks and mesquites, respectively, on a projected canopy area basis. These coefficients indicate that mesquites (so called xeric trees) use more water than oaks (so called mesic trees) under non-limiting conditions. Stomatal resistances (r(s)) were calculated using the PM equation, and ranged from 20 to 200 s cm⁻¹. Calibrations were developed between r(s) and net radiation for both species. Results of the PM model to predict daily tree water use ranged from -15 to +150 percent error, depending on the tree, indicating the need for accurate measurements of stomatal resistance in order to use the PM model. Results indicate that a shortened form of the PM equation requiring only vapor pressure deficit and r(s) would be sufficient to predict tree water use.
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Wang, Xin. "Linking Hydroperiod with Water Use and Nutrient Accumulation in Wetland Tree Islands." Scholarly Repository, 2011. http://scholarlyrepository.miami.edu/oa_dissertations/531.
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Many large terrestrial ecosystems have patterned landscapes as a result of a positive feedback system between vegetation communities and environmental factors. One example is tree island habitats in the Florida Everglades. Although they only occupy a small portion of the Everglades landscape, tree islands are important features as the focus of nutrient accumulation and wildlife biodiversity in the Everglades ecosystem. The hardwood hammock community on the elevated head of tree island habitats can accumulate high phosphorus concentration in the otherwise P-limited Everglades ecosystem. In this dissertation, I examined two hypotheses derived from the chemohydrodynamic nutrient accumulation model, which suggests that high transpiration of tree island hammock plants is the driving force for nutrient accumulation in tree island soil. According to this model, I hypothesized that tree islands with lower dry season transpiration should have less phosphorus accumulated than the tree islands with higher dry season transpiration. By examining the water use and nutrient status from 18 tree islands in both slough (perennially wet) and prairie (seasonally wet) locations, I was able to compare water availability and nutrient accumulation in slough and prairie tree islands with different marsh hydroperiods. Chapter 1 uses elemental and stable isotope analysis to look at water stress and nutrient concentration in tree island plants. I showed that the prairie tree island plants suffer from drought stress during the dry season, when the marshes in the prairies dry out. Prairie tree islands also have lower soil and plant P concentration than the slough tree islands. Moreover, I showed that foliar N isotope ratio serves as a stable proxy for community level P availability for tree island plants, and prairie tree island plants have less P available than slough tree island plants. In Chapter 2, I showed that the satellite imagery derived normalized difference water index (NDWI) provides a robust indicator of community level canopy water content of these tree islands. NDWI, used as a proxy for water status, was positively related to foliar N isotope ratio, which suggests that water availability is linked to nutrient availability in the tree island hardwood hammock plant communities. These findings are consistent to the chemohydrodynamic nutrient accumulation model. In Chapter 3, I used sap flow sensors on individual trees to provide a real-time measurement of plant transpiration. I showed that tree island plant transpiration is affected by multiple factors including weather fluctuations, marsh water depth regulated by local water management, and canopy structure of different tree islands. Overall, my dissertation establishes a link between tree island plant water use and nutrient accumulation. It could be potentially important for future restoration plan of tree islands and Everglades hydrological management.
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Gush, Mark Baudert. "Water-use, growth and water-use efficiency of indigenous tree species in a range of forest and woodland systems in South Africa." Doctoral thesis, University of Cape Town, 2011. http://hdl.handle.net/11427/10565.
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This study was initiated to explore whether indigenous tree species use less water than introduced plantation tree species, whether they use that water more efficiently in terms of biomass accumulation, and consequently whether there is scope for the expansion of indigenous tree production systems in South Africa.
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Mapeto, Tatenda. "Single tree water use and water-use efficiencies of selected indigenous and introduced forest species in the southern Cape region of South Africa." Thesis, Nelson Mandela Metropolitan University, 2015. http://hdl.handle.net/10948/11493.
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In South Africa, the limited extent of indigenous forests accelerated the development of fast-growing introduced species plantations, on which the country is now heavily reliant for its fibre and timber products. However, the plantation forestry industry is challenged with limited freshwater resources, the need for sustainable management of introduced tree species in commercial forest production systems, and a diversity of plant ecological production factors such as soils that have to be manipulated for the purposes of increasing production capacities. Additionally, plantations are established in the limited high rainfall regions of the country and the industry’s water use has been regulated since 1972. Conversely, natural forests also provide valuable goods, however, their slow growth rates have restricted their development as commercial tree production systems. In this regard the forestry industry is continuously seeking to provide for the country’s timber and fibre needs while ensuring the provision of other ecosystem services from tree production systems. Recent developments in the forestry industry have therefore been focused on water use efficiency in current and alternative tree production systems. There is also widespread unsubstantiated belief that indigenous tree species are efficient users of water. Against this background this study sought to explore the single tree water use and water use efficiencies of introduced commercial plantation species (Pinus radiata) and that of important indigenous species (Ilex mitis, Ocotea bullata and Podocarpus latifolius) for timber and fibre production in the southern Cape region of South Africa. Single tree water use measurements were carried out for a year using the heat pulse velocity method. Growth measurements for utilisable stem wood were done on a quarterly basis for the specimen trees and growth increments over the year were determined. Single tree water use efficiency was a calculated as a function of grams of stem wood gained per litre of water transpired. Measurements of daily weather conditions and soil water content were concurrently taken during the year. The relationships between the variables that express daily climatic conditions, soil water content and daily volumes of transpired water were explored. Empirical models for the prediction of daily transpiration as a function of climate and soil water content were then developed using multiple linear regression analysis. Pinus radiata trees exhibited higher totals of volumetric transpiration than the indigenous species. The water use patterns of Pinus radiata showed higher peaks of maximum and minimum daily and seasonal water use while the indigenous species showed temperate patterns of water use throughout the year. Podocarpus latifolius attained the lowest water use efficiency in the year (0.49g/L) while Pinus radiata, Ocotea bullata and Ilex mitis had comparable water use efficiency values ranging between 1g/L to 2.50g/L. Significant positive correlations existed between climatic variables and daily sapflow volumes of the tree specimens. Daily total solar radiation showed the highest positive correlation with daily transpiration and the average value of the correlation coefficient for solar radiation and water use for all tree species was 0.70 (p < 0.001). Empirical models for predicting daily water use integrated the variables expressing plant available moisture and energy. The study enhances our understanding of single tree water use, water use efficiency, the drivers of transpiration and the applicability of such studies in developing rapid estimation techniques for water use in current and alternative South African tree production systems.
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Snyder, Keirith Ann. "Environmental and physiological controls on water source use by semi-arid riparian tree species." Diss., The University of Arizona, 2001. http://hdl.handle.net/10150/279782.
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A general paradigm in semi-arid and arid systems is that woody plants with dimorphic root systems will exhibit preferential use of deeper soil water because it represents a more stable source of water than short duration pulses of shallow soil moisture derived from summer rainfall. However, whether this holds across all woody species and whether use of deeper soil water interacts with use of shallow soil water is not determined for many species in different ecosystems. Understanding the amount of water plants derive from groundwater and shallow soil water is critically important to accurate calculations of local and regional water balance. The focus of this research was to determine if dominant woody species in semi-arid riparian ecosystems used shallow soil water and how depth to groundwater and defoliation might affect root proliferation and water uptake. This research found that the functional grouping "phreatophytes" encompasses a variety of responses to environmental variation. Stable isotopic analyses determined that Prosopis velutina Woot. (Velvet mesquite) and Populus fremontii Wats. (Fremont cottonwood) used shallow soil water derived from summer rainfall, and the proportion of shallow soil water was higher at sites with greater depth to groundwater. In contrast Salix gooddingii Ball (Goodding willow) did not use shallow soil water at any location regardless of depth to groundwater. Field experiments using defoliation treatments, to limit carbon assimilation and reduce plant photosynthate pools, confirmed that Prosopis velutina exhibited flexible response in water uptake patterns in response to defoliation. Defoliation, which presumably reduced available photosynthate, increased the reliance of this species on shallow soil water; contrary to predictions that woody species should maintain extensive deep root systems to buffer themselves from seasonal drought. Greenhouse experiments with Populus fremontii and Prosopis velutina also indicated changes in belowground biomass of fine roots, which were associated with changes in water-source use for Populus fremontii, but not for Prosopis velutina. These results imply that in terms of predicting plant response to changes in future climates, or modeling fluxes of water from the soil to the atmosphere that are largely controlled by plant transpiration, intra- and interspecific variability will need to be considered.
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Bunnell, Michael Cameron. "Water Use of Four Commonly Planted Landscape Tree Species in a Semi-Arid Suburban Environment." BYU ScholarsArchive, 2015. https://scholarsarchive.byu.edu/etd/6146.
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Native plant communities and agricultural land are commonly converted to urban areas as cities across the Western United States continue to grow and expand. This expansion is typically accompanied by afforestation where a common goal among communities is to maximize shade tree composition. Planted forests in these regions are commonly composed of introduced tree species native to mesic environments and their ability to persist is dependent on consistent irrigation inputs. Many potential ecosystem services may be derived from planting trees in urban and suburban areas; however, there are also costs associated with extensive afforestation, and shade tree cover may have significant implications on municipal water budgets. In this study I evaluate variation in daily and seasonal water use of regionally common suburban landscape tree species in the Heber Valley (Wasatch County, Utah). I had two primary objectives: (1) to identify and understand the differences in transpiration between landscape tree species in a suburban setting and (2) to assess the sensitivity of sap flux and transpiration to variation in vapor pressure deficit, wind speed, and incoming shortwave radiation. I used Granier's thermal dissipation method to measure the temperature difference (ΔT) between two sap flux probes. The empirical equation developed by Granier was used to convert ΔT into sap flux density (Jo) measurements, which were then scaled to whole-tree transpiration. There were consistent and substantial differences in sap flux between tree species. I found that Picea pungens under irrigated growing conditions, on average, had Jo rates that were 32% greater and whole tree water use (ET) rates that were 550% greater than all other species studied. The findings of Jo may be partially explained by xylem architecture and physiological control over stomatal aperture. However, the rate of water flux in the outermost portion of sapwood does not necessarily determine the magnitude of whole tree transpiration. Rather, ET in this study was largely explained by the combined effects of irrigation, tree size, and sapwood to heartwood ratio.
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Hasnat, Abul, University of Western Sydney, of Science Technology and Environment College, and School of Environment and Agriculture. "Soil-water use and irrigation scheduling under fruit tree-turf alley cropping system in Hawkesbury Area." THESIS_CSTE_EAG_Hasnat_A.xml, 2003. http://handle.uws.edu.au:8081/1959.7/614.
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Efficient use of irrigation and nutrients are becoming increasingly important in commercial orchards in the Hawkesbury area. Proper irrigation scheduling practices can help in the better use of irrigation water and reduce environmental impacts. Field experiments were conducted during February 1999 to June 2000 to understand soil-water use, and to evaluate farmer’s irrigation practice under an alley cropping system consisting of turf and stone fruits. The study was carried out at Atlas Farm, 3.5 km from the University of Western Sydney, Hawkesbury campus. The experimental site is a floodplain of the Hawkesbury River. The river flows within 1 km of the farm boundaries. The study was conducted under the farmer’s existing irrigation water and nutrient management practices. The main aims of the thesis were to study the movement and redistribution of soil-water and soil-moisture dynamics in the turf and stone fruit alley cropping system and to understand deep percolation losses and nitrogen leaching using the water balance approach. The study indicated that drainage occurred mainly after heavy rainfall and when there was rainfall for a few consecutive days. Thus irrigation application should be delayed if there is a likelihood of rain in a few consecutive days to prevent loss of water due to deep drainage. Furthermore, the study showed irrigation scheduling was essential to reduce nitrate leaching in the field; that irrigation depths should be varied according to the stage of crop growth, and the proper timing of irrigation application could help reduce deep percolation and runoff losses.Master of Science (Hons) (Agriculture)
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Ahongshangbam, Joyson [Verfasser]. "Tree and oil palm water use: scaling, spatial heterogeneity and temporal dynamics (Sumatra, Indonesia) / Joyson Ahongshangbam." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2020. http://d-nb.info/122090936X/34.
Full textBooks on the topic "Tree water use"
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R, Calder Ian, Hall R. L, and Adlard P. G, eds. Growth and water use of forest plantations. Chichester, West Sussex, England: Wiley, 1992.
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Ramírez, Joaquín Sosa. Agua y sustentabilidad en Aguascalientes: Tres ensayos. [Aguascalientes]: CIEMA, 1998.
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Rumpf, Georg Eberhard. The Ambonese herbal: Being a description of the most noteworthy trees, shrubs, herbs, land- and water-plants which are found in Amboina and the surrounding islands according to their shape, various names, cultivation, and use : together with several insects and animals : for the most part with the figures pertaining to them : all gathered with much trouble and diligence over many years and described in twelve books. New Haven [Conn.]: Yale University Press, 2010.
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The Ambonese herbal: Being a description of the most noteworthy trees, shrubs, herbs, land- and water-plants which are found in Amboina and the surrounding islands according to their shape, various names, cultivation, and use : together with several insects and animals : for the most part with the figures pertaining to them : all gathered with much trouble and diligence over many years and described in twelve books. New Haven [Conn.]: Yale University Press, 2010.
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Dyer, Harriet. Little Book of Going Green: Really Understand Climate Change, Use Greener Products, Adopt a Tree, Save Water, and Much More! Skyhorse Publishing Company, Incorporated, 2019.
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Connellan, Geoff. Water Use Efficiency for Irrigated Turf and Landscape. CSIRO Publishing, 2013. http://dx.doi.org/10.1071/9780643106888.
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Achieving high water use efficiency in maintaining turf, trees and landscape areas is a core responsibility of open space managers. Water Use Efficiency for Irrigated Turf and Landscape provides a logical and scientifically sound approach to irrigation in urban areas in Australia. It is based on green space delivering defined outcomes using the principles of water sensitive urban design and irrigation efficiency.
The book covers all stages of the water pathway – from the source to delivery into the plant root zone. Major topics include system planning, estimating water demand, water quality, irrigation systems, soil management and irrigation performance evaluation.
Clearly presented explanations are included, as well as line drawings and worked examples, and a plant water use database covering more than 250 plant species. A Water Management Planning template is included to guide water managers and operators through a process that will deliver a sound plan to achieve sustainable turf, urban trees and landscapes.
Best Management Practice Irrigation principles are outlined and their implementation in open space turf and landscape situations is explained. The benefits and limitations of the various methods of delivering water to plants are covered, together with case studies and guidelines for specific horticultural situations. Methodologies to evaluate irrigated sites are included along with recommended benchmark values.
The book presents the latest irrigation technology, including developments in water application, control technology and environmental sensors such as weather stations, soil moisture sensors and rain sensors.
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Books, PetCraze. Pet Tree Python Care Notes: Customized Easy to Use, Daily Pet Snake Accessories Care Log Book to Look after All Your Pet Snake's Needs. Great for Recording Feeding, Water, Health, Cleaning, Tank Temperature, and Equipment Maintenance. Independently Published, 2020.
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Nambiar, Sadanandan, and Ian Ferguson. New Forests. CSIRO Publishing, 2005. http://dx.doi.org/10.1071/9780643093089.
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There is no question that the timber industry needs to adopt sustainable practices that ensure a future for the industry. This book goes well beyond simply growing commercial tree plantations for wood production. It explores new forests that can supply environmental services such as salinity mitigation and carbon sequestration together with commercial wood production in an environment beyond the boundaries of traditional forestry.
New Forests targets agricultural landscapes affected by salinity and which generally have rainfall less than 650 mm per year. The book addresses vital issues such as where tree planting might best be pursued, what species and technologies should be used for establishment and later management, how productivity can be improved, what mix of environmental services and commercial goods is optimum, and whether the likely net benefits justify the change in land use and requisite investment.
While the book is focussed on the low-rainfall, agricultural, inland zone of the Murray-Darling Basin wherever possible the scope of most chapters has been expanded to synthesise generic information applicable to other regions in Australia and elsewhere.
The authors provide a comprehensive account of all the issues relevant to the development of these new forests, covering soils, the bio-physical environment, water use and irrigation strategies - including the use of wastewater, silviculture, pests and diseases, wood quality and products, and economics and policy implications.
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Murray, Helene. Managing water use and growth of a perennial ryegrass living mulch in Christmas trees. 1988.
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Stahle, David W., Dorian J. Burnette, Daniel Griffin, and Edward R. Cook. Thirteenth Century AD. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780199329199.003.0009.
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The hypothesis that a prolonged drought across southwestern North America in the late thirteenth century contributed to the abandonment of the region by Ancestral Pueblo populations, ultimately including the depopulation of the Mesa Verde region, continues to be a focus of archaeological research in the Pueblo region. We address the hypothesis through the re-measurement of tree-ring specimens from living trees and archaeological wood at Mesa Verde, Colorado, to derive chronologies of earlywood, latewood, and total ring width. The three chronology types all date from AD 480 to 2008 and were used to separately reconstruct cool and early warm season effective moisture and total water-year precipitation for Chapin Mesa near many of the major prehistoric archaeological sites. The new reconstructions indicate three simultaneous cool and early growing season droughts during the twelfth and thirteenth centuries that may have contributed to the environmental and social factors behind Ancestral Pueblo migrations over this sector of the Colorado Plateau. These sustained inter-seasonal droughts included the “Great Drought” of the late-thirteenth century, which is estimated to have been one of the most severe regimes of cool and early summer drought in the last 1,500-years and coincided with the end of Puebloan occupations at Mesa Verde. The elevation of the 30 cm isohyet of water-year precipitation reconstructed for southwestern Colorado from the new ring-width data is mapped from AD 1276–1280 and identifies areas where dry-land cultivation of maize may not have been practical during the driest years of the Great Drought. There is no doubt about the exact dating of the tree-ring chronologies, but the low sample size of dated specimens from Mesa Verde during the late-thirteenth and fourteenth centuries contributes uncertainty to these environmental reconstructions at the time of abandonment.
Book chapters on the topic "Tree water use"
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Allen, Scott T., Matthias Sprenger, Gabriel J. Bowen, and J. Renée Brooks. "Spatial and Temporal Variations in Plant Source Water: O and H Isotope Ratios from Precipitation to Xylem Water." In Stable Isotopes in Tree Rings, 501–35. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-030-92698-4_18.
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AbstractThe water present within trees when sugars and cellulose are formed is the source of hydrogen and oxygen atoms that are incorporated into tree-ring cellulose (see Chaps. 10.1007/978-3-030-92698-4_10 and 10.1007/978-3-030-92698-4_11). However, the isotope composition of relevant water pools is often unknown when trying to interpret δ18O and δ2H isotopic records in tree rings. This chapter focuses on the factors that can influence the O and H isotope ratios of source waters for trees. Trees generally use water that originated as precipitation, but this does not mean that the isotope ratios of water used by trees—predominantly taken up by roots from soils—and incorporated in cellulose exactly matches precipitation isotope ratios. Precipitation isotope ratios vary in space and time, and only a fraction of all precipitation infiltrates soils, reaches roots, and is ultimately taken up by trees. Considering species, soils, and climates may allow for predicting which fraction of water resides in the root-zone during the growing seasons, and how its isotope ratios deviate from that of average precipitation. Here we provide an overview of the terrestrial water cycle and the associated transport and fractionation processes that influence the stable isotope ratios of water used by trees. We highlight obstacles and opportunities to be considered, towards more accurately interpreting the records of O and H isotope ratios in tree cellulose.
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Allen, Scott T., Matthias Sprenger, Gabriel J. Bowen, and J. Renée Brooks. "Spatial and Temporal Variations in Plant Source Water: O and H Isotope Ratios from Precipitation to Xylem Water." In Stable Isotopes in Tree Rings, 501–35. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-030-92698-4_18.
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AbstractThe water present within trees when sugars and cellulose are formed is the source of hydrogen and oxygen atoms that are incorporated into tree-ring cellulose (see Chaps. 10.1007/978-3-030-92698-4_10 and 10.1007/978-3-030-92698-4_11). However, the isotope composition of relevant water pools is often unknown when trying to interpret δ18O and δ2H isotopic records in tree rings. This chapter focuses on the factors that can influence the O and H isotope ratios of source waters for trees. Trees generally use water that originated as precipitation, but this does not mean that the isotope ratios of water used by trees—predominantly taken up by roots from soils—and incorporated in cellulose exactly matches precipitation isotope ratios. Precipitation isotope ratios vary in space and time, and only a fraction of all precipitation infiltrates soils, reaches roots, and is ultimately taken up by trees. Considering species, soils, and climates may allow for predicting which fraction of water resides in the root-zone during the growing seasons, and how its isotope ratios deviate from that of average precipitation. Here we provide an overview of the terrestrial water cycle and the associated transport and fractionation processes that influence the stable isotope ratios of water used by trees. We highlight obstacles and opportunities to be considered, towards more accurately interpreting the records of O and H isotope ratios in tree cellulose.
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Ewers, Brent E., Ben Bond-Lamberty, and D. Scott Mackay. "Consequences of Stand Age and Species’ Functional Trait Changes on Ecosystem Water Use of Forests." In Tree Physiology, 481–505. Dordrecht: Springer Netherlands, 2011. http://dx.doi.org/10.1007/978-94-007-1242-3_18.
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Saurer, Matthias, and Steve Voelker. "Intrinsic Water-Use Efficiency Derived from Stable Carbon Isotopes of Tree-Rings." In Stable Isotopes in Tree Rings, 481–98. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-030-92698-4_17.
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AbstractStable carbon isotopes in tree-rings are not only useful to derive climatic information of the past. Based on the isotope fractionations during uptake and fixation of CO2, physiological information can be retrieved, namely the ratio of assimilation to stomatal conductance, which is termed the intrinsic water-use efficiency (iWUE). This crucial plant physiological trait varies among species and environments and is characteristic of how much water is lost from leaves for a certain carbon gain. iWUE is of great importance at the scale of individual plants because it can determine plant performance and survival. iWUE also contributes how closely canopy- or ecosystem-scale carbon and water fluxes are coupled or divergent, which has implications for understanding biogeochemical cycling. Carbon isotopes in tree-rings can be used to estimate how iWUE of trees has changed in the past, e.g. due to increasing CO2, nitrogen or other factors. Accordingly, many applications have explored this tool for various forest ecosystems across the globe, often reporting a strong increase in iWUE over the twentieth century. Explicit comparisons of tree-ring iWUE to growth-data obtained from the same rings can help distinguish among strategies plants employ under various environmental impacts, like increasing CO2, light limitation, drought or too much water. In this chapter, we describe the theory behind iWUE, show some limitations of the method, give examples of the combined application of iWUE and tree-ring width, discuss photosynthetic limitations of iWUE and finally show how the method has been applied in large-scale tree-ring networks.
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Dracup, John A., and Donald R. Kendall. "Risk and Reliability in Predicting Droughts: The Use of Prehistoric Tree-Ring Data." In Water Resources Engineering Risk Assessment, 435–58. Berlin, Heidelberg: Springer Berlin Heidelberg, 1991. http://dx.doi.org/10.1007/978-3-642-76971-9_23.
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Baltrėnaitė, Edita, Pranas Baltrėnas, and Arvydas Lietuvninkas. "Use of Wood Products for Water and Soil Quality Improvement." In The Sustainable Role of the Tree in Environmental Protection Technologies, 185–248. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-25477-7_6.
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Green, Steve, Brent Clothier, Horst Caspari, and Sue Neal. "Rootzone processes, tree water-use, and the equitable allocation of irrigation water to olives." In Environmental Mechanics: Water, Mass and Energy Transfer in the Biosphere, 337–45. Washington, D. C.: American Geophysical Union, 2002. http://dx.doi.org/10.1029/129gm28.
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Kalma, S. J., P. J. Thorburn, and G. M. Dunn. "Using Heat Pulse and Deuterium Tracing Techniques to Estimate Tree Water Use." In Subsurface Hydrological Responses to Land Cover and Land Use Changes, 47–60. Boston, MA: Springer US, 1997. http://dx.doi.org/10.1007/978-1-4615-6141-5_4.
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DeJong, T. M. "The carbohydrate economy of fruit trees." In Concepts for understanding fruit trees, 27–34. Wallingford: CABI, 2022. http://dx.doi.org/10.1079/9781800620865.0005.
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Abstract Since lack of water is a commonly occurring condition in nature, plants have developed many physiological responses to help them survive periods of water stress. Most of these responses cause changes in the carbohydrate economy of the tree through reduced photosynthesis, tree growth or cropping, but some of these effects can be managed to have minimal impact on overall tree productivity. Whether these responses influence economic production depends on: (i) the processes occurring at the time of a stress; (ii) how important these processes are to tree yield; and (iii) whether these processes rely heavily on the current level of photosynthesis or can use stored carbohydrates, like starch, to compensate for the lack of current photosynthesis in the leaves. This chapter discusses the carbohydrate economy of fruit trees. An outline is provided for how assimilates are distributed and used within a fruit or nut tree.
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Wullschleger, Stan D., and Paul J. Hanson. "Sensitivity of Sapling and Mature-Tree Water Use to Altered Precipitation Regimes." In Ecological Studies, 87–99. New York, NY: Springer New York, 2003. http://dx.doi.org/10.1007/978-1-4613-0021-2_6.
Full textConference papers on the topic "Tree water use"
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Gupta, Apurva, John Murray, Bin Li, Harish Mukundan, and Anis Hussain. "Use of a Stem Device for VIV Mitigation on a Dry Tree Semi-Submersible." In ASME 2009 28th International Conference on Ocean, Offshore and Arctic Engineering. ASMEDC, 2009. http://dx.doi.org/10.1115/omae2009-80010.
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The offshore industry is devoting considerable effort to develop a dry tree production Semi-submersible with motion characteristics similar to a Spar but with the functionality of a Tension Leg Platform (TLP) or a Semi-submersible in terms of fabrication, installation and commissioning. Installation of these Semi-submersibles in the Gulf of Mexico environment exposes the risers to high surface current which result in high fatigue damage due to Vortex Induced Vibration (VIV). In the existing dry tree production systems, the Spar shields the riser from the high velocity surface currents in depths to approximately 600 ft. In the dry tree Semi-submersible the upper sections of the risers are exposed to surface currents. In addition, most dry tree Semi-submersibles designs have to support Keel Joints similar to a Spar. Thus, installing and replacing conventional VIV mitigation devices like the fairings and strakes could become difficult. In comparison, the TLP has no keel guides making it easier to install risers with strakes or fairings to improve the riser’s response to currents in terms of VIV. There are two basic proven techniques to reduce VIV damage on a riser. These involve application of standard fairings or strakes and direct protection of an exposed riser to currents. This paper discusses a methodology for VIV suppression using a riser stem. This mechanism does not reduce the VIV directly on the riser, but it in fact shields the riser from the surface currents, and thus reduces the fatigue damage on risers. This riser is shielded inside a conduit section called a stem which extends from the deck of the Semi-submersible to the keel. The paper quantifies and discusses the reduction in fatigue damage when the stem is used. The analysis is based on typical deep water current conditions for the Gulf of Mexico.
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Steen, Atle, Mike Tognarelli, Lixin Xu, and Hugh Banon. "Dry Tree Semisubmersible Options for Deepwater Production." In ASME 2002 21st International Conference on Offshore Mechanics and Arctic Engineering. ASMEDC, 2002. http://dx.doi.org/10.1115/omae2002-28619.
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Recent deep water field developments have made increasing use of dry tree completions from floating production units, principally spars and TLPs. There are a number of development efforts underway to include dry tree semi-submersibles in deep water. The use of dry tree semis requires some form of heave suppression as well as a means for limiting pitch motions. Two concepts using this principle include the DPS 2001 and the TPG 3300. Both of these concepts consist of a deck supported on columns and, in the case of the DPS-2001, pontoons. In each case there is a submerged heave plate to trap mass and to dampen the heave motions. Risers must pass through this heave plate. This paper will present the results of study of options supporting top tensioned risers from these platforms, with a focus on the DPS-2001. Air Cans and tensioners have both been investigated. Air cans have been used on all spar platforms to date, but in this case the cans are shielded by the spar hull and are not exposed to wave kinematics or current loads. Tensioners have been used on all the TLPs, but their stroke is less than would be required for a semi-submersible, even one that is heave compensated. The tensioners used in this study had a relatively high stiffness in order to reduce stroke. This results in a coupling of the motions of the hull with the risers and results in some increase in the peak tensions. It also results in a lower heave period and higher heave motions. The paper will discuss the technical and economic tradeoffs for these options.
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Murray, John J., Chan K. Yang, Cheng-Yo Chen, and Edwin Nah. "Two Dry Tree Semisubmersible Designs for Ultra Deep Water Post-Katrina Gulf of Mexico." In ASME 2008 27th International Conference on Offshore Mechanics and Arctic Engineering. ASMEDC, 2008. http://dx.doi.org/10.1115/omae2008-57462.
Full textAbstract:
The increased interest in floater designs for ultra-deep water has produced a number of dry tree semisubmersible designs that allow the use of top tensioned risers (TTRs). The primary advantage of the TTRs is that they facilitate direct vertical access to production wells and thereby offer access for well completions and interventions. The principle behind several of the dry tree semisubmersible designs is to reduce the motions of a traditional shaped semisubmersible to a level that can accommodate TTRs. This is accomplished by using heave plates that are positioned beneath the semisubmersible hull and are supported by a lower structure, such as a truss. To a certain extent, the motion responses above and below the response amplitude operator (RAO) cancellation period can be manipulated by designing the relative sizes of the pontoons and columns as well as the size and depth of the heave plates such that the sum of the forces interacts to minimize the heave motion. The paper presents and discusses two semisubmersible designs that assume a common topsides and riser payload. The two designs are sized and analyzed for the new Gulf of Mexico metocean criteria. The comparison is based on hull dimensions, including heave plate and structural support construction. In both cases, results of the hull performance predicted by numerical simulations from fully coupled models are compared and discussed.
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Kubo, Kotaro, Keita Fujiwara, Yoichi Tanaka, Yuto Hakuta, Daisuke Arake, Tomoaki Uchiyama, and Ken Muramatsu. "A Scoping Study on the Use of Direct Quantification of Fault Tree Using Monte Carlo Simulation in Seismic Probabilistic Risk Assessments." In 2022 29th International Conference on Nuclear Engineering. American Society of Mechanical Engineers, 2022. http://dx.doi.org/10.1115/icone29-88773.
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Abstract After the Fukushima Daiichi Nuclear Power Plant accident, the importance of conducting probabilistic risk assessments (PRAs) of external events, especially seismic activities and tsunamis, was recognized. The Japan Atomic Energy Agency has been developing a computational methodology for seismic PRA, called the direct quantification of fault tree using Monte Carlo simulation (DQFM). When appropriate correlation matrices are available for seismic responses and capacities of components, the DQFM makes it possible to consider the effect of correlated failures of components connected through AND and/or OR gates in fault trees, which is practically difficult when methods using analytical solutions or multidimensional numerical integrations are used to obtain minimal cut set probabilities. The usefulness of DQFM has already been demonstrated. Nevertheless, a reduction of the computational time of DQFM would allow the large number of analyses required in PRAs conducted by regulators and/or operators. We therefore performed scoping calculations using three different approaches, namely quasi-Monte Carlo sampling, importance sampling, and parallel computing, to improve calculation efficiency. These were applied when calculating the conditional core damage probability of a simplified PRA model of a pressurized water reactor, using the DQFM method. The results indicated that the quasi-Monte Carlo sampling works well at assumed medium and high ground motion levels, the importance sampling is suitable for assumed low ground motion level, and that the parallel computing enables practical uncertainty and importance analyses. The combined implementation of these improvements in a PRA code is expected to provide a significant acceleration of computation and offers the prospect of practical use of DQFM in risk-informed decision-making.
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Mansour, Alaa M. "FHS Semi: A Semisubmersible Design for Dry Tree Applications." In ASME 2009 28th International Conference on Ocean, Offshore and Arctic Engineering. ASMEDC, 2009. http://dx.doi.org/10.1115/omae2009-79303.
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In this paper the performance of a new conceptual semisubmersible design that provides motion response similar to a Spar is investigated. The new invention introduces a new feature which is the Free-Hanging Solid Ballast Tank, hence the name FHS Semi. The use of the free-hanging Solid Ballast Tank (SBT) significantly increases the heave natural period while controlling the heave response in the wave frequency range and, therefore, enables the use of the FHS Semi in dry tree applications. The new design’s quayside integration technique and its interface with the top tensioned risers are presented in this paper. Case study for the new design to support a 32,000 ST payload including 15 Top Tensioned Risers (TTRs) in an ultra-deepwater of 8,000 ft water depth is considered. Frequency domain and fully coupled time-domain hydrodynamic analyses have been performed and numerical results are presented to illustrate the new semisubmersible design response in extreme Gulf of Mexico hurricane events.
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Lee, Ming-Yao, Jack Zeng, and Philip Poll. "The State of Dry-Tree Semi-Submersible Platforms for Deepwater Gulf of Mexico." In ASME 2014 33rd International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/omae2014-23236.
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The use of semi-submersible platforms has become increasingly popular due to its ability to carry large topsides and the possibility for quayside integration. With recent exploration successes in ultra-deepwater fields of the Gulf of Mexico, major oil and engineering companies are keen to look for a safe, reliable and cost-effective dry-tree option to maximize the value of deepwater field developments. Dry-tree semi-submersible (DTS) emerges as such an option to overcome the water depth and size limits imposed by TLP and Spar, respectively, and enables the platform to carry a large well array and payloads in ultra-deep water. This paper presents the offshore industry’s multi-year efforts to mature two promising semi-submersible platform concepts that can accommodate long-stroke dry-tree risers and have large drilling and production capabilities. Results of technology development and qualification will be highlighted with details on hull performance and hull/riser interfaces. Key structural, mooring and riser analyses and scaled model test results including the long-stroke riser tensioning system will be presented. Remaining challenges that need to be overcome to advance the DTS concepts from “technology acceptance” to “project readiness” will also be discussed.
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Srinivasan, Kumar, Z. J. Wang, Wei Yuan, and Richard Sun. "Vehicle Thermal Management Simulation Using a Rapid Omni-Tree Based Adaptive Cartesian Mesh Generation Methodology." In ASME 2004 Heat Transfer/Fluids Engineering Summer Conference. ASMEDC, 2004. http://dx.doi.org/10.1115/ht-fed2004-56748.
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CFD simulation of vehicle under-hood and under-body poses several challenges. Specifically, the complexity of the geometry involved makes the use of traditional mesh generation approaches, based on the boundary-to-interior methodology, impractical and time consuming. The current work presents the use of an interior-to-boundary method wherein the need for creating a ‘water-tight’ surface mesh is not a pre-requisite for volume mesh generation. The application of the new method is demonstrated for an actual passenger vehicle under-hood model with nearly a hundred components. Coupled radiation/convection simulations are performed to obtain the complete airflow and thermal map of the engine compartment. Results are validated with test data. The new method results in significant gains in efficiency over traditional approaches allowing the simulation tool to be used effectively in the vehicle development process.
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Martin, Bruce, Oriol Rijken, and Kent Davies. "Experimental Validation of a Numerical Model for a Dry-Tree Semisubmersible in Benign Environments." In ASME 2014 33rd International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/omae2014-24185.
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The offshore industry has spent the last several years developing semisubmersible platforms capable of supporting both drilling and production activities. The production trees are located on top of the top tensioned risers (TTRs) on a Dry Tree Semisubmersible. A key challenge in the design of these vessels is to reduce the heave motion as much as possible to enable the use of state-of-the-art riser tensioners. A model test campaign was executed as part of the developmental program. The primary objective of this campaign was to improve the accuracy of the numerical tools to be used in the design process. Riser tensioners are typically hydro-pneumatic devices, with a nonlinear tension-stroke relationship. A riser tensioner was developed at model scale which had a similar nonlinear behavior to the prototype. Examining the effect of this tensioner on the global motions was an additional objective of this test campaign. The techniques used to model this nonlinear spring is described, and its effect on global motions investigated. A key challenge in model testing platforms intended for ultra-deep water (e.g. greater than 7000 ft) is the modeling of the mooring and riser system. The premise for the design of the model mooring system is 1.) maintain as best as possible the force-offset relationship of the mooring lines and 2.) be able to describe the model test configuration in the numerical tools to be used for global design. The near taut behavior of the prototype mooring system is modeled using heavy chain and a high-catenary mooring line.
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Singh, Jasbindra, Mustafa Lawati, Abdulkareem Hindawi, Mohammed Harthi, Abdel Samiee Rady, Mohammed Al Hinai, Marya Al Salmi, et al. "Greening the Desert While Helping Business and Caring for the Environment." In Abu Dhabi International Petroleum Exhibition & Conference. SPE, 2021. http://dx.doi.org/10.2118/207307-ms.
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Abstract This paper describes the utilization of produced and treated formation water for planting trees and growing algae in large ponds; in a massive scale in South Oman. A detailed study has been carried out to assess the injection requirements for pressure maintenance in the producing reservoir and using the remaining excess pot-treated water for farming of the palm trees. The produced water has been used as disposal in formations deeper than the producing horizons in the past. The produced water was separated in a processing station that received gross production from a number of fields in South Oman. This water was disposed in the aquifer underlying a producing reservoir that has experienced pressure maintenance due to this disposal. The impact of this excess water disposal on the aquifer was studied to evaluate the risk of breaching cap rock integrity. The risk was not significant but to ensure "no damage to the environment and people" it was decided to reduce or optimize injection rates to maintain the reservoir pressure safeguarding reserves. In addition, the disposal of the water required significant amount of power equivalent to emitting significant amount of CO2 annually just for water disposal. The study was carried out using simple material balance methods to predict the pressure behaviour given an injection profile. The recommendations from the study have already been implemented to convert the deep-water disposal to injection in the aquifer. This has been achieved by the integration of number of interfaces from sub-surface to field operations. All the pieces are in place to take it the next level of execution that is to treat the water at surface for oil removal, hence rendering the water at acceptable quality levels for tree plantation and algae ponds. The project also aims in a future second phase to further treat the water to higher specifications allowing the use of it for agricultural purposes. This would introduce a commercial farm that will depend on this source of water. This would be a novel concept in South Oman where the treated water will be used for farming solving multiple issues at multiple levels namely helping the business achieve its objective of sustained oil production, helping local communities with employment via farming and helping the organization care for the environment by reducing carbon footprints.
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Janoff, Dwight. "Flexible, High Temperature Thermal Insulation Materials for Subsea Wellhead and Production Equipment." In ASME 2002 21st International Conference on Offshore Mechanics and Arctic Engineering. ASMEDC, 2002. http://dx.doi.org/10.1115/omae2002-28392.
Full textAbstract:
As oil and gas wells are being drilled in deepwater, hydrate formation in the well has become a major concern. During a production shut down, gas hydrates can form and plug the bore of a subsea tree, tree piping, jumper, manifold and flow lines. During shut downs, hot produced fluids become stagnant and are cooled by the surrounding cold water, resulting in hydrate formation [1]. Thermal insulation is necessary to slow down this cooling process to prevent hydrate formation until the well production or hydrate inhibitor injection can be restored [2]. Currently available insulation materials for subsea applications are rated for internal temperatures of up to 121 °C (250 °F). These materials include NovoTherm, urethanes, and epoxy/syntactic foams, and vulcanized rubbers [3]. These materials may thermally age at above 121 °C (250 °F) such that the insulation bond line will become weakened or softened over time. Recently, insulation that will withstand 177 °C (350 °F) internal temperatures for high temperature, high pressure (HTHP) projects are being required by operators. Two new insulation materials, proposed for use on subsea wellhead and production systems at temperatures up to 177 °C (350 °F) will be discussed. The first material is based on addition cured silicone elastomer. The second material is based on a flexible Novolac epoxy. Both materials are cast in place into molds, have high tensile elongation, and possess the thermal properties necessary to meet cool down requirements for subsea production equipment. These materials are being proposed for use on manifolds, jumpers, production trees, and other subsea equipment.
Reports on the topic "Tree water use"
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Cohen, Shabtai, Melvin Tyree, Amos Naor, Alan N. Lakso, Terence L. Robinson, and Yehezkiel Cohen. Influence of hydraulic properties of rootstocks and the rootstock-scion graft on water use and productivity of apple trees. United States Department of Agriculture, 2001. http://dx.doi.org/10.32747/2001.7587219.bard.
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This one year exploratory project investigated hydraulic architecture of apple dwarfing rootstocks. The hypothesis was that hydraulic conductance is correlated with rootstock vigor. A previous study of trees on three rootstocks in Israel showed that dwarfed trees used less water than un-dwarfed trees. Analysis showed that if the tree maintains leaf water potentials above minimum values, then this implies that the dwarfed trees have lower leaf conductance, which may also be the cause of dwarfing. The current project studied small 2-year old unworked rootstock trees, and full sized trees bearing commercial yields. In both cases hydraulic conductance was determined with two methods - the non-destructive evaporative flux (EF)-leaf water potential (L WP) method, and a destructive method in which water was forced through the plant at known pressure using the "high pressure flow meter" (HPFM). Detailed work allowed measurement of conductance of the rootstock-scion union. This was achieved both with the HPFM and with the EF-LWP methods, the former in the US and the latter in Israel. Direct measurements of leaf conductance were made, and carbon isotope ratios ( d ¹³ C) were determined for leaves sampled at the end of the season. The latter can indicate sustained differences in leaf conductance behavior. HPFM and EF-LWP methods did not give the same results. In the small plants results were similar in magnitude, but not significantly correlated. In large trees, EF- L WP measurements were a fraction of those obtained with the HPFM. The latter indicates that some of the xylem is not normally functional but transports water when pressurized. Additional experimental work targeted this result. Xylem was stained before and after perfusion with water at high pressure. This showed that at least for one rootstock a significant amount of xylem was blocked before perfusion. The "air method" for determining xylem vessel properties was improved and employed. Length, radius and density of xylem vessels of different rootstocks were found to be similar, and significant differences found were not clearly related to rootstock vigor. Measurements in the commercial orchard in Israel showed that the graft union in a dwarfing rootstock was a large obstacle for water transport (i.e. had a high resistance). This apparently led to low leaf conductance to water vapor, as indicated by lower d ¹³ C, which implies low internal CO ₂ concentrations. In the US orchard, d ¹³ C in 2001 was correlated with rootstock vigor, and significant differences were found in leaf conductance. However, the d ¹³ C differences were not observed in 2002, were opposite to those found in the Israeli orchard, and measurements of the graft union with the HPFM did not find large resistances. We speculate that the graft union is not necessarily a large impediment to water transport unless the scion starts to separate from the rootstock. It was concluded that significant differences in hydraulic conductance exist between different dwarfing rootstocks. These differences may be caused by differences in xylem properties and in the degree of cavitation, as well as resistance in the graft union. However, no general relationship to rootstock vigor was found. Therefore, hydraulic conductance alone cannot explain dwarfing, but may be one of two or more factors that lead to dwarfing. Future work should integrate more factors with hydraulic relations, e.g. nutrient and solute transport and production of hormones.
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Dasberg, Shmuel, Jan W. Hopmans, Larry J. Schwankl, and Dani Or. Drip Irrigation Management by TDR Monitoring of Soil Water and Solute Distribution. United States Department of Agriculture, August 1993. http://dx.doi.org/10.32747/1993.7568095.bard.
Full textAbstract:
Drip irrigation has the potential of high water use efficiency, but actual water measurement is difficult because of the limited wetted volume. Two long-term experiments in orchards in Israel and in California and several field crop studies supported by this project have demonstrated the feasibility of precise monitoring of soil water distribution for drip irrigation in spite of the limited soil wetting. Time Domain Reflectometry (TDR) enables in situ measurement of soil water content of well defined small volumes. Several approaches were tried in monitoring the soil water balance in the field during drip irrigation. These also facilitated the estimation of water uptake: 1. The use of multilevel moisture probe TDR system. This approach proved to be of limited value because of the extremely small diameter of measurement. 2. The placement of 20 cm long TDR probes at predetermined distances from the drippers in citrus orchards. 3. Heavy instrumentation with neutron scattering access tubes and tensiometers of a single drip irrigated almond tree. 4. High resolution spatial and temporal measurements (0.1m x 0.1m grid) of water content by TDR in corn irrigated by surface and subsurface drip. The latter approach was accompanied by parametric modelling of water uptake intensity patterns by corn roots and superimposed with analytical solutions for water flow from point and line sources. All this lead to general and physically based suggestions for the placement of soil water sensors for scheduling drip irrigation.
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Hochmair, Hartwig, Adam Benjamin, Daniel Gann, Levente Juhasz, and Zhaohui Fu. Miami-Dade County Urban Tree Canopy Analysis. Florida International University, 2021. http://dx.doi.org/10.25148/gis.009116.
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This assessment focuses on describing urban tree canopy (UTC) within the Urban Development Boundary of Miami-Dade County, as defined by the Miami-Dade County Transportation Planning Organization (Figure 1). The area (intracoastal water areas excluded) encompasses approximately 1147 km2 (443 mi2). A combination of remote sensing and publicly available vector data was used to classify the following land cover classes: tree canopy/shrubs, grass, bare ground, wetland, water, building, street/railroad, other impervious surfaces, and cropland.
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Saltus, Christina, and Eric Britzke. Literature review : macrohabitat metrics to identify presence of chiroptera on the landscape in the United States. Engineer Research and Development Center (U.S.), September 2022. http://dx.doi.org/10.21079/11681/45523.
Full textAbstract:
This special report reviews current scientific literature to identify the most commonly cited metrics used to describe the macrohabitat criteria important for Chiroptera presence in the United States. The review evaluates 69 scientific articles from 1994 to 2018. The most commonly cited metrics were divided into four main categories: tree-species-level metrics, landscape-level metrics, distance metrics, and topographic and atmospheric metrics. Of all metrics found, the top six most common metrics noted across all articles were percent canopy cover, diameter at breast height (DBH), forest type, distance to water, distance to roads or other urban features, and tree density. In addition, 27 of the 47 (57%) bat species located within the United States were represented. These metrics provide important insight into the regional or national species-level distribution and assist with modeling the relationship between species distribution and habitat change.
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Furman, Alex, Jan Hopmans, Shmuel Assouline, Jirka Simunek, and Jim Richards. Soil Environmental Effects on Root Growth and Uptake Dynamics for Irrigated Systems. United States Department of Agriculture, February 2011. http://dx.doi.org/10.32747/2011.7592118.bard.
Full textAbstract:
Root water uptake is perhaps the most important unknown in the mass balance of hydrological and agricultural systems. The understanding and the ability to predict root uptake and the way it is influence by environmental conditions has great potential in increasing water and fertilizer use efficiency and allowing better control of water and contaminant leach towards groundwater. This BARD supported research is composed of several components, including a) intensive laboratory work for the quantification of root uptake and the way it is controlled by environmental conditions; b) development of tools for laboratory and field use that can help in sensing very low water fluxes and water content, which is a necessity for studying root uptake; c) development of capabilities to model compensated root uptake; and d) development of a database that will allow calibration of such a model. In addition some auxiliary research was performed as reported later. Some of the components, and especially the modeling and the HPP development, were completed in the framework of the project and even published in the international literature. The completed components provide a modeling environment that allows testing root compensated uptake modeling, a tool that is extremely important for true mechanistic understanding of root uptake and irrigation design that is based on mechanistic and not partially based myth. The new button HPP provides extended level of utilization of this important tool. As discussed below, other components did not get to maturity stage during the period of the project, but comprehensive datasets were collected and will be analyzed in the near future. A comprehensive dataset of high temporal and spatial resolution water contents for two different setups was recorded and should allow us understanding f the uptake at these fine resolutions. Additional important information about root growth dynamics and its dependence in environmental conditions was achieved in both Israel and the US. Overall, this BARD supported project provided insight on many important phenomena related to root uptake and to high resolution monitoring in the vadose zone. Although perhaps not to the level that we initially hoped for, we achieved better understanding of the related processes, better modeling capabilities, and better datasets that will allow continuation of this effort in the near future.
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Bell, Gary, David Abraham, Gaurav Savant, and Anthony G. Emiren. Hydrodynamics in the Morganza Floodway and Atchafalaya Basin, report 3 : phase 3; a report for the US Army Corps of Engineers, MRG&P. Engineer Research and Development Center (U.S.), January 2022. http://dx.doi.org/10.21079/11681/42800.
Full textAbstract:
The Morganza Floodway and the Atchafalaya Basin, located in Louisiana west of the Mississippi River, were evaluated using a two-dimensional Adaptive Hydraulics model. Prior to this study, Phase 1 and 2 model studies were performed that indicated that the existing floodway may not be able to pass the Project Design Flood discharge of 600,000 cubic feet per second due to levee overtopping. In this study, all elevations of exterior and interior levees were updated with current crest elevations. In addition, the Phase 3 effort evaluated the sensitivity of the floodway’s flow capacity to variations in tree/vegetation density conditions. These adjustments in roughness will improve the understanding of the role of land cover characteristics in the simulated water surfaces. This study also provides a number of inundation maps corresponding to certain flows through the Morganza Control Structure.
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Dick, Warren, Yona Chen, and Maurice Watson. Improving nutrient availability in alkaline coal combustion by-products amended with composted animal manures. United States Department of Agriculture, 2002. http://dx.doi.org/10.32747/2002.7587240.bard.
Full textAbstract:
Hypothesis and Objectives: We hypothesized that coal combustion products (CCPs), including those created during scrubbing of sulfur dioxide from flue gases, can be used alone or mixed with composted animal manures as effective growth media for plants. Our specific objectives were, therefore, to (1) measure the chemical, physical and hydraulic properties of source materials and prepared mixes, (2) determine the optimum design mix of CCPs and composted animal manures for growth of plants, (3) evaluate the leachate water quality and plant uptake of selected elements from prepared mixes, (4) quantify the interaction between composted animal manures and B concentrations in the mixes, (5) study the availability of P to plants growing in the mixes, and (6) determine the microbial community and siderophores involved in the solubilization of Fe and its transfer to plants. Background: In recent years a major expansion of electricity production by coal combustion has taken place in Israel, the United States and the rest of the world. As a result, a large amount of CCPs are created that include bottom ash, fly ash, flue gas desulfurization (FGD) gypsum and other combustion products. In Israel 100,000 tons of fly ash (10% of total CCPs) are produced each year and in the US a total of 123 million tons of CCPs are produced each year with 71 million tons of fly ash, 18 million tons of bottom ash and 12 million tons of FGD gypsum. Many new scrubbers are being installed and will come on-line in the next 2 to 10 years and this will greatly expand the amount of FGD gypsum. One of the main substrates used in Israel for growth media is volcanic ash (scoria; tuff). The resemblance of bottom coal ash to tuff led us to the assumption that it is possible to substitute tuff with bottom ash. Similarly, bottom ash and FGD gypsum were considered excellent materials for creating growth mixes for agricultural and nursery production uses. In the experiments conducted, bottom ash was studied in Israel and bottom ash, fly ash and FGD gypsum was studied in the US. Major Achievements: In the US, mixes were tested that combine bottom ash, organic amendments (i.e. composts) and FGD gypsum and the best mixes supported growth of tomato, wheat and marigolds that were equal to or better than two commercial mixes used as a positive control. Plants grown on bottom ash in Israel also performed very well and microelements and radionuclides analyses conducted on plants grown on bottom coal ash proved it is safe to ingest the edible organs of these plants. According to these findings, approval to use bottom coal ash for growing vegetables and fruits was issued by the Israeli Ministry of Health. Implications: Bottom coal ash is a suitable substitute for volcanic ash (scoria; tuff) obtained from the Golan Heights as a growth medium in Israel. Recycling of bottom coal ash is more environmentally sustainable than mining a nonrenewable resource. The use of mixes containing CCPs was shown feasible for growing plants in the United States and is now being evaluated at a commercial nursery where red sunset maple trees are being grown in a pot-in-pot production system. In addition, because of the large amount of FGD gypsum that will become available, its use for production of agronomic crops is being expanded due to success of this study.
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Dick, Warren, Yona Chen, and Maurice Watson. Improving nutrient availability in alkaline coal combustion by-products amended with composted animal manures. United States Department of Agriculture, December 2006. http://dx.doi.org/10.32747/2006.7695883.bard.
Full textAbstract:
Hypothesis and Objectives: We hypothesized that coal combustion products (CCPs), including those created during scrubbing of sulfur dioxide from flue gases, can be used alone or mixed with composted animal manures as effective growth media for plants. Our specific objectives were, therefore, to (1) measure the chemical, physical and hydraulic properties of source materials and prepared mixes, (2) determine the optimum design mix of CCPs and composted animal manures for growth of plants, (3) evaluate the leachate water quality and plant uptake of selected elements from prepared mixes, (4) quantify the interaction between composted animal manures and B concentrations in the mixes, (5) study the availability of P to plants growing in the mixes, and (6) determine the microbial community and siderophores involved in the solubilization of Fe and its transfer to plants. Background: In recent years a major expansion of electricity production by coal combustion has taken place in Israel, the United States and the rest of the world. As a result, a large amount of CCPs are created that include bottom ash, fly ash, flue gas desulfurization (FGD) gypsum and other combustion products. In Israel 100,000 tons of fly ash (10% of total CCPs) are produced each year and in the US a total of 123 million tons of CCPs are produced each year with 71 million tons of fly ash, 18 million tons of bottom ash and 12 million tons of FGD gypsum. Many new scrubbers are being installed and will come on-line in the next 2 to 10 years and this will greatly expand the amount of FGD gypsum. One of the main substrates used in Israel for growth media is volcanic ash (scoria; tuff). The resemblance of bottom coal ash to tuff led us to the assumption that it is possible to substitute tuff with bottom ash. Similarly, bottom ash and FGD gypsum were considered excellent materials for creating growth mixes for agricultural and nursery production uses. In the experiments conducted, bottom ash was studied in Israel and bottom ash, fly ash and FGD gypsum was studied in the US. Major Achievements: In the US, mixes were tested that combine bottom ash, organic amendments (i.e. composts) and FGD gypsum and the best mixes supported growth of tomato, wheat and marigolds that were equal to or better than two commercial mixes used as a positive control. Plants grown on bottom ash in Israel also performed very well and microelements and radionuclides analyses conducted on plants grown on bottom coal ash proved it is safe to ingest the edible organs of these plants. According to these findings, approval to use bottom coal ash for growing vegetables and fruits was issued by the Israeli Ministry of Health. Implications: Bottom coal ash is a suitable substitute for volcanic ash (scoria; tuff) obtained from the Golan Heights as a growth medium in Israel. Recycling of bottom coal ash is more environmentally sustainable than mining a nonrenewable resource. The use of mixes containing CCPs was shown feasible for growing plants in the United States and is now being evaluated at a commercial nursery where red sunset maple trees are being grown in a pot-in-pot production system. In addition, because of the large amount of FGD gypsum that will become available, its use for production of agronomic crops is being expanded due to success of this study.
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Mayfield, Colin. Capacity Development in the Water Sector: the case of Massive Open On-line Courses. United Nations University Institute for Water, Environment and Health, January 2017. http://dx.doi.org/10.53328/mwud6984.
Full textAbstract:
The Sustainable Development Goal 6 targets are all dependent on capacity development as outlined in SDG 6a “Expand international cooperation and capacity-building support to developing countries in water- and sanitation related activities and programmes “. Massive Open On-line Courses (MOOCs) and distance learning in general have a significant role to play in this expansion. This report examines the role that MOOCs and similar courses could play in capacity development in the water sector. The appearance of MOOCs in 2010/11 led within 4 years to a huge increase in this type of course and in student enrollment. Some problems with student dropout rates, over-estimating the transformational and disruptive nature of MOOCs and uncertain business models remain, but less “massive” MOOCs with more engaged students are overcoming these problems. There are many existing distance learning courses and programmes in the water sector designed to train and/ or educate professionals, operators, graduate and undergraduate students and, to a lesser extent, members of communities dealing with water issues. There are few existing true MOOCs in the water sector. MOOCs could supply significant numbers of qualified practitioners for the water sector. A suite of programmes on water-related topics would allow anyone to try the courses and determine whether they were appropriate and useful. If they were, the students could officially enroll in the course or programme to gain a meaningful qualification or simply to upgrade their qualifications. To make MOOCs more relevant to education and training in the water sector an analysis of the requirements in the sector and the potential demand for such courses is required. Cooperation between institutions preparing MOOCs would be desirable given the substantial time and funding required to produce excellent quality courses. One attractive model for cooperation would be to produce modules on all aspects of water and sanitation dealing with technical, scientific, social, legal and management topics. These should be produced by recognized experts in each field and should be “stand-alone” or complete in themselves. If all modules were made freely available, users or mentors could assemble different MOOCs by linking relevant modules. Then extracts, simplified or less technical versions of the modules could then be used to produce presentations to encourage public participation and for other training purposes. Adaptive learning, where course materials are more tailored to individual students based on their test results and reactions to the material, can be an integral part of MOOCs. MOOCs efficiently provide access to quality courses at low or no cost to students around the world, they enable students to try courses at their convenience, they can be tailored to both professional and technical aspects, and they are very suitable to provide adaptive learning courses. Cooperation between institutions would provide many course modules for the water sector that collectively could provide excellent programmes to address the challenges of capacity development for SDG 6 and other issues within the water sector.
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Hovav, Ran, Peggy Ozias-Akins, and Scott A. Jackson. The genetics of pod-filling in peanut under water-limiting conditions. United States Department of Agriculture, January 2012. http://dx.doi.org/10.32747/2012.7597923.bard.
Full textAbstract:
Pod-filling, an important yield-determining stage is strongly influenced by water stress. This is particularly true for peanut (Arachishypogaea), wherein pods are developed underground and are directly affected by the water condition. Pod-filling in peanut has a significant genetic component as well, since genotypes are considerably varied in their pod-fill (PF) and seed-fill (SF) potential. The goals of this research were to: Examine the effects of genotype, irrigation, and genotype X irrigation on PF and SF. Detect global changes in mRNA and metabolites levels that accompany PF and SF. Explore the response of the duplicate peanut pod transcriptome to drought stress. Study how entire duplicated PF regulatory processes are networked within a polyploid organism. Discover locus-specific SNP markers and map pod quality traits under different environments. The research included genotypes and segregating populations from Israel and US that are varied in PF, SF and their tolerance to water deficit. Initially, an extensive field trial was conducted to investigate the effects of genotype, irrigation, and genotype X irrigation on PF and SF. Significant irrigation and genotypic effect was observed for the two main PF related traits, "seed ratio" and "dead-end ratio", demonstrating that reduction in irrigation directly influences the developing pods as a result of low water potential. Although the Irrigation × Genotype interaction was not statistically significant, one genotype (line 53) was found to be more sensitive to low irrigation treatments. Two RNAseq studies were simultaneously conducted in IL and the USA to characterize expression changes that accompany shell ("source") and seed ("sink") biogenesis in peanut. Both studies showed that SF and PF processes are very dynamic and undergo very rapid change in the accumulation of RNA, nutrients, and oil. Some genotypes differ in transcript accumulation rates, which can explain their difference in SF and PF potential; like cvHanoch that was found to be more enriched than line 53 in processes involving the generation of metabolites and energy at the beginning of seed development. Interestingly, an opposite situation was found in pericarp development, wherein rapid cell wall maturation processes were up-regulated in line 53. Although no significant effect was found for the irrigation level on seed transcriptome in general, and particularly on subgenomic assignment (that was found almost comparable to a 1:1 for A- and B- subgenomes), more specific homoeologous expression changes associated with particular biosynthesis pathways were found. For example, some significant A- and B- biases were observed in particular parts of the oil related gene expression network and several candidate genes with potential influence on oil content and SF were further examined. Substation achievement of the current program was the development and application of new SNP detection and mapping methods for peanut. Two major efforts on this direction were performed. In IL, a GBS approach was developed to map pod quality traits on Hanoch X 53 F2/F3 generations. Although the GBS approach was found to be less effective for our genetic system, it still succeeded to find significant mapping locations for several traits like testa color (linkage A10), number of seeds/pods (A5) and pod wart resistance (B7). In the USA, a SNP array was developed and applied for peanut, which is based on whole genome re-sequencing of 20 genotypes. This chip was used to map pod quality related traits in a Tifrunner x NC3033 RIL population. It was phenotyped for three years, including a new x-ray method to phenotype seed-fill and seed density. The total map size was 1229.7 cM with 1320 markers assigned. Based on this linkage map, 21 QTLs were identified for the traits 16/64 weight, kernel percentage, seed and pod weight, double pod and pod area. Collectively, this research serves as the first fundamental effort in peanut for understanding the PF and SF components, as a whole, and as influenced by the irrigation level. Results of the proposed study will also generate information and materials that will benefit peanut breeding by facilitating selection for reduced linkage drag during introgression of disease resistance traits into elite cultivars. BARD Report - Project4540 Page 2 of 10