 Jun-Yan will talk about plant hydraulic strategies and impact on ecosystem processes, and it's in the Southern Sheriffs. Can you see the screen? Yes, we can. Okay. Yeah, thanks. I'm Jun-Yan. I'm the postdoc at the Lawrence Berkeley Lab. So my project is to look at the plant hydraulic strategy of quantified forage and its impact on the forage ecosystem process at Southern Sierra, California. So just a little bit background on the plant hydraulics, treat uptake water through the root system, and then it move the water through the pipe-like network of the stem, which is called the xylean, and deliver it to the leaf where it transpires through the stoma. Meanwhile, the stoma will uptake carbon dioxide from photosynthesis. So the plants can have deep roots versus shallow roots, and in the xylean, it can be safer in efficient while unsafe in efficient. That means the tree can transpire water very fast, but easily form air bubble in the xylean, which will cause damage to the trees, and the leaf can be sensitive. So the stoma of the leaf can be sensitive or insensitive in terms of the vapor pressure deficit. So those plant hydraulic traits will affect the interaction between the vegetation structure and the plant growth, and their effects on the climate and the surface structure in the process, like the soil moisture and the soil property. So the study area is in California. We have the Mediterranean climate here, and we also have the drought. So in California, the most precipitation are fall and winter, while the energy supply is during the summer. And also, in 2015, California drought and the cost, 90% of the tree died at the southern Sierra mid-elevation region. So the place here is dominated by the ponderosa pine. So in general, the precipitation at the wet year is some of the 500,000 millimeter, but it's 4 to 700 millimeter in general dry year. But in 2014, it goes low to 400 millimeter. So the overall objective of the study is to explore the effects of the plant hydraulic traits on the ecosystem function in the process, and especially looking at their stress on the tree productivity and drought induced stress. So the approach is to use numerical experiment using the functional assembly to ratio ecosystem simulation of the hydraulic version of that model that incorporates the plant hydraulic dynamic into the ecosystem model and their feedback to the environment. So the model system is some Sierra, see those sites. The sub the super catchment of that critical observatory site. So for the model setup, I use the static then the structure that from the consensus data and the random model for five, five years, some period that before the pre drought and some period during the drought. So there are the two different quantities, more quantities there. The pine have the sensitive stoma unsafe for the island and the deep roots while the Cedar has insensitive stoma safe for our inefficient as island and the shower roots. So I look at the ecosystem variable, the gross primary productivity evapotranspiration runoff soil moisture and the standard content. So the results. This is simulated evapotranspiration and the growth primary productivity. And for pine has higher growth primary productivity and the transpiration during the normal year. So from 2010 to 2012. Well, it has much lower growth primary productivity and also the transpiration rate during the drought. So the observed the pattern from similar pie simulation is more consistent with the flux tower measurement, which I didn't plot here. Well, in terms of the Cedar, the simulated results shows the Cedar will have much lower GPP and the transpiration during the drought and also the dry season. And while the seed can maintain the similar level of the GPP and the transpiration during drought in compare with the pine. So the effects of the runoff and the soil moisture point has deep roots. So during the preach out that the deep roots will facilitate the uptake of the deep moisture and the compare to the Cedar. So for the pine. If the soil moisture at the lower layer can get very dry and for the seed from the Cedar simulation. So the lower the lower layer of the soil maintains relatively high or so water content. And during the drought, the pine continue to dry the soil moisture at the lower layer to be very dry. And the soil moisture at the lower layer from the Cedar simulation maintains relatively high even during the drought period. So as a result, the Cedar, if the site is dominated the Cedar, it will result have higher runoff during the normal year compared to the pine and also during the drought. Cedar have some runoff while if the pine dominates, there is no runoff from the site. In the still water content, it is the measure of the drought stress in the tree mortality. If the stain has high water content that the tree will has lower drought stress and the lower mortality while if the stain has lower water content, then the tree will experience severe drought stress and mortality. In terms of the pine, the blue line, because the pine has deep roots, it allows the tree access more water so it can maintain higher stain water content during the free drought condition and can maintain longer duration of the high stain water content. On the other hand, during the drought, pine can efficiently transpire water and also deep roots reduce the deep water in the soil. So the pine experience significant loss of the stain water content. And for the Cedar, shallow roots during the free drought will result in lower stain water content, but it maintain more or less the same during the drought. In summary, where the supply of energy and the water is disynchronized and the surface storage capacity is close to any precipitate. So at that site, pine with deep roots and the efficient xerion can fully utilize surface storage and the precipitation for productivity. This will result in less runoff and the lower soil water content. This is a strategy for high productivity, but it makes the pine to be more vulnerable to run the drought. So if the site is dominated by the pine, the site will have higher vegetative coverage, but it can be significantly reduced when severe drought occurs. The Cedar has shallow roots and the safer xerion. So this makes Cedar can only use shallow surface water storage capacity and leave deep moisture untouched. This results in more runoff, higher soil water content. Therefore, less precipitation used for productivity, but this will also let Cedar to be less susceptible to drought. And if the site is dominated by the Cedar, then the site will have less vegetation coverage, but that will remain the same through the drought. Okay, thanks, that's all.