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Summary Observational evidence indicates that tree leaf area may acclimate in response to changes in water availability to alleviate hydraulic stress. However, the underlying mechanisms driving leaf area changes and consequences of different leaf area allocation strategies remain unknown.Here, we use a trait‐based hydraulically enabled tree model with two endmember leaf area allocation strategies, aimed at either maximizing carbon gain or moderating hydraulic stress. We examined the impacts of these strategies on future plant stress and productivity.Allocating leaf area to maximize carbon gain increased productivity with high CO2, but systematically increased hydraulic stress. Following an allocation strategy to avoid increased future hydraulic stress missed out on 26% of the potential future net primary productivity in some geographies. Both endmember leaf area allocation strategies resulted in leaf area decreases under future climate scenarios, contrary to Earth system model (ESM) predictions.Leaf area acclimation to avoid increased hydraulic stress (and potentially the risk of accelerated mortality) was possible, but led to reduced carbon gain. Accounting for plant hydraulic effects on canopy acclimation in ESMs could limit or reverse current projections of future increases in leaf area, with consequences for the carbon and water cycles, and surface energy budgets.
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Optimizing fluid viscosity for systems of multiple hydraulic fractures
Abstract Optimal hydraulic fracturing stimulations of horizontal oil and gas wells maximize created fracture surface area and/or maximize the uniformity of stimulation. Here, we use a new, rapidly‐computing hydraulic fracture model to investigate how surface area and uniformity are impacted by interplay among multiple growing hydraulic fractures driven through permeable rocks by fluids of various viscosities. The results show the existence of a surface‐area‐optimizing viscosity that is large enough to control leak‐off but not so large that leads to unnecessarily large fracture aperture.
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- Award ID(s):
- 1645246
- PAR ID:
- 10461475
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- AIChE Journal
- Volume:
- 65
- Issue:
- 5
- ISSN:
- 0001-1541
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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