Add new study: Creek_2018

[yangsophieee]

Add study on coordination between leaf, stem, and root hydraulics and gas exchange in three arid-zone angiosperms during severe drought and recovery.

Questions for review:

• I can't really figure out how many replicates there are for a lot of these traits
  • Experiment 1: "As the drought progressed, individual plants were targeted for leaf gas exchange, whole canopy transpiration, and midday water potential... harvested for leaf, stem, and root hydraulic measurements in the lab."
  • Experiment 2: "During recovery, leaf-level gas exchange and whole canopy transpiration, as well as leaf, stem, and root hydraulics were measured in subgroups of 4–5 plants per species at 1, 3, 14, and 28 days after soil rewetting. A smaller group of control plants (n = 3) per species were maintained under well-watered conditions throughout the experiment."
  • "we measured gas exchange, E, and midday Ψleaf in a number of additional plants to those targeted for hydraulics."
  • "In both the drought response and recovery experiments, we measured leaf-level photosynthesis... Leaves that had been measured for gas exchange (one per individual) were... measured"
  • It's very difficult to estimate how many replicates they did when they didn't specify explicitly.
• Quite a few traits for which I'm not sure what to match to, maybe they aren't in AusTraits, so I've put them in the questions section

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Codecov Report

Patch and project coverage have no change.

Comparison is base (93d014c) 80.20% compared to head (2031f37) 80.20%.

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[ehwenk]

Add study on coordination between leaf, stem, and root hydraulics and gas exchange in three arid-zone angiosperms during severe drought and recovery.

Questions for review:

* I can't really figure out how many replicates there are for a lot of these traits

  * Experiment 1: "As the drought progressed, **individual plants were targeted** for leaf gas exchange, whole canopy transpiration, and midday water potential... harvested for leaf, stem, and root hydraulic measurements in the lab."
  * Experiment 2: "During recovery, leaf-level gas exchange and whole canopy transpiration, as well as leaf, stem, and root hydraulics were measured in **subgroups of 4–5 plants per species** at 1, 3, 14, and 28 days after soil rewetting. A smaller group of control plants (_n_ = 3) per species were maintained under well-watered conditions throughout the experiment."
  * "we measured gas exchange, _E_, and midday Ψleaf in a **number of additional plants to those targeted for hydraulics**."
  * "**In both the drought response and recovery experiment**s, we measured leaf-level photosynthesis... Leaves that had been measured for gas exchange (one per individual) were... measured"
  * It's very difficult to estimate how many replicates they did when they didn't specify explicitly.

* Quite a few traits for which I'm not sure what to match to, maybe they aren't in AusTraits, so I've put them in the questions section

Let's leave this pull request for a few days. I've just one of the authors on the paper - because I think this is a dataset where we'd prefer to have the individual-level values so we can properly capture all the context properties.

[ehwenk]

I haven't heard back from anyone about the data set and feel like it is now too late to try and source the data before I leave. I've reviewed it, added in some new traits, and I think the right decision for now is to merge this in and we can revisit it later.

[yangsophieee]

Daniel has asked that we do not merge this yet.

And I've just updated the units based on the reasoning that the water potential at 12, 50 and 88 percent loss of conductivity for leaf, stem and root are based on the drought response experiment, hence replicates = 15-20.

In April 2016, when the plants of each species were at least 50 cm tall, we assigned plants to two different subexperiments. (a) Drought response experiment: a group of 15–20 plants per species were exposed to a single drought treatment during which the response of leaf gas exchange and hydraulic conductance in leaves, stems, and roots to decreasing water potential was measured. (b) Recovery response experiment: immediately following the completion of Experiment 1, a second group of 15–20 plants per species were dried down to a narrow range of water potentials associated with significant stem hydraulic dysfunction and then rewatered to field capacity after which the recovery of leaf gas exchange and hydraulic traits was measured. ^p Experiment 2: Recovery response ^p To characterize the recovery of plant function following drought, plants of each species were dried down to a target minimum water potential associated with approximately 50% loss in stem hydraulic conductance (as predicted from each species vulnerability curve generated from Experiment 1), after which they were rewatered and soil water content was maintained at field capacity.