1 00:00:08,102 --> 00:00:11,930 - For this last talk of the technology and innovation track, 2 00:00:11,930 --> 00:00:16,620 we have Al Freeman here, a PhD candidate 3 00:00:16,620 --> 00:00:18,720 with the Rubenstein School of Environment 4 00:00:18,720 --> 00:00:21,853 and Natural Resources within the University of Vermont. 5 00:00:22,960 --> 00:00:25,087 I will be sharing their presentation titled 6 00:00:25,087 --> 00:00:28,923 "Assessing the Efficacy of Assisted Migration, 7 00:00:29,930 --> 00:00:33,430 Physiological Response of Seedlings to Moderate Severity 8 00:00:33,430 --> 00:00:36,107 Drought and Adaptive Civil Culture Treatments." 9 00:00:36,107 --> 00:00:38,020 - [Al] Today I'm gonna be talking about 10 00:00:38,020 --> 00:00:41,160 the physiological response of future adapted seedlings 11 00:00:41,160 --> 00:00:42,820 to a moderate severity drought 12 00:00:42,820 --> 00:00:46,053 at the adaptive civil culture for climate change project. 13 00:00:47,900 --> 00:00:50,170 It's important to note that climate regimes 14 00:00:50,170 --> 00:00:52,350 are actually changing at a much faster rate 15 00:00:52,350 --> 00:00:56,780 than natural migration has keep pace with. 16 00:00:56,780 --> 00:00:59,170 And so recent species distribution models 17 00:00:59,170 --> 00:01:01,560 are actually showing that the Northeast 18 00:01:01,560 --> 00:01:03,710 is gonna be prime for migration 19 00:01:03,710 --> 00:01:07,940 with increases in habitat for future adapted species 20 00:01:07,940 --> 00:01:10,070 that are expected to either enrich 21 00:01:10,070 --> 00:01:12,440 the population of the site. 22 00:01:12,440 --> 00:01:14,560 So again, these species that are found there, 23 00:01:14,560 --> 00:01:16,420 but aren't in high abundance 24 00:01:16,420 --> 00:01:20,180 or as species that are not currently present on the site, 25 00:01:20,180 --> 00:01:22,113 but may increase their range. 26 00:01:23,130 --> 00:01:25,290 And so this lack of natural migration 27 00:01:25,290 --> 00:01:28,300 and potential for this new suitable habitat 28 00:01:28,300 --> 00:01:32,270 has led to the idea of using a system migration 29 00:01:32,270 --> 00:01:36,623 to aid kind of in climate adaptation of our forests. 30 00:01:37,860 --> 00:01:40,790 Because effectively transitioning forests through management 31 00:01:40,790 --> 00:01:42,070 will take decades, 32 00:01:42,070 --> 00:01:45,790 it's really important that we start investigating right now, 33 00:01:45,790 --> 00:01:48,380 how we can best shift our ecosystems 34 00:01:48,380 --> 00:01:50,410 towards these more novel states 35 00:01:50,410 --> 00:01:52,230 and build mechanisms to resist 36 00:01:52,230 --> 00:01:54,540 these changing climate regimes. 37 00:01:54,540 --> 00:01:56,920 And so three different strategies have been proposed 38 00:01:56,920 --> 00:02:00,423 as a means for managing with climate resiliency in mind. 39 00:02:01,360 --> 00:02:04,260 So the first one is resistance. 40 00:02:04,260 --> 00:02:06,580 The goal of this is really to improve defenses 41 00:02:06,580 --> 00:02:08,880 of forest management against change 42 00:02:08,880 --> 00:02:10,500 and disturbance by maintaining 43 00:02:10,500 --> 00:02:13,623 kind of relatively unchanged conditions. 44 00:02:15,980 --> 00:02:18,150 Second treatment is resilience. 45 00:02:18,150 --> 00:02:21,690 And so resilience adds a bit more complexity to the system 46 00:02:21,690 --> 00:02:24,220 and accommodates some degree of change 47 00:02:24,220 --> 00:02:26,810 with the ultimate goal still being to return to 48 00:02:26,810 --> 00:02:30,120 a prior reference condition following disturbance. 49 00:02:30,120 --> 00:02:32,210 And this can be accomplished by performing 50 00:02:32,210 --> 00:02:33,960 some civil cultural prescriptions, 51 00:02:33,960 --> 00:02:37,090 like a matrix of thinning with varying gap sizes, 52 00:02:37,090 --> 00:02:39,520 to add a little bit more structural complexity 53 00:02:39,520 --> 00:02:40,683 into the system. 54 00:02:42,150 --> 00:02:44,510 Last, we have the transition treatment, 55 00:02:44,510 --> 00:02:47,650 which is intentionally trying to facilitate change 56 00:02:47,650 --> 00:02:50,270 in the system and surprise, 57 00:02:50,270 --> 00:02:54,290 transition the site to be adaptively responsive. 58 00:02:54,290 --> 00:02:57,430 And so this can kind of be accomplished 59 00:02:57,430 --> 00:02:59,980 through creating a matrix of thinning with gaps 60 00:02:59,980 --> 00:03:01,520 and planting those species 61 00:03:01,520 --> 00:03:05,380 that we kind of talked about before that are future adapted, 62 00:03:05,380 --> 00:03:08,870 to add a little bit more variation and complexity. 63 00:03:08,870 --> 00:03:11,630 These three different strategies have led to the development 64 00:03:11,630 --> 00:03:13,210 of what is referred to as the 65 00:03:13,210 --> 00:03:16,430 Adaptive Civil Culture for Climate Change Project 66 00:03:16,430 --> 00:03:18,170 or the ASCC Project, 67 00:03:18,170 --> 00:03:21,370 which is the largest replicated forest management experiment 68 00:03:21,370 --> 00:03:23,040 in the Northeast U.S. 69 00:03:23,040 --> 00:03:24,970 And it was co-produced by managers, 70 00:03:24,970 --> 00:03:28,010 scientists, biologists, and stakeholders. 71 00:03:28,010 --> 00:03:31,810 So it's this huge effort that has led to the development 72 00:03:31,810 --> 00:03:34,510 of these effective strategies for forest management 73 00:03:34,510 --> 00:03:37,053 with climate mitigation in mind. 74 00:03:38,150 --> 00:03:41,680 The main goal of the project is to implement actions 75 00:03:41,680 --> 00:03:44,000 that are robust across a range 76 00:03:44,000 --> 00:03:46,653 of potential future conditions. 77 00:03:50,030 --> 00:03:53,170 The ASCC Project is located at the Second College Grant, 78 00:03:53,170 --> 00:03:56,550 and you can see in this figure here below, 79 00:03:56,550 --> 00:03:58,640 this is kind of what the treatments look like. 80 00:03:58,640 --> 00:04:01,050 So we have the control treatments here. 81 00:04:01,050 --> 00:04:04,730 We have our resistance treatments, our resilience, 82 00:04:04,730 --> 00:04:07,410 so adding a little bit more complexity in there, 83 00:04:07,410 --> 00:04:09,550 and then we have our transition treatments 84 00:04:09,550 --> 00:04:12,340 where we have quarter acre and one acre gaps. 85 00:04:12,340 --> 00:04:13,800 And within these gaps, 86 00:04:13,800 --> 00:04:17,280 we have actually planted seedlings that are expected to have 87 00:04:17,280 --> 00:04:21,550 either a population expansion or enrichment. 88 00:04:21,550 --> 00:04:24,070 So again, species that are found on the site, 89 00:04:24,070 --> 00:04:26,890 but we're increasing the abundance of those individuals 90 00:04:26,890 --> 00:04:29,090 because they're expected to perform better 91 00:04:29,090 --> 00:04:31,570 under future climate conditions. 92 00:04:31,570 --> 00:04:33,230 We also have species that are 93 00:04:33,230 --> 00:04:35,480 expected to have a range expansion. 94 00:04:35,480 --> 00:04:38,260 So ones that are not currently found on the site, 95 00:04:38,260 --> 00:04:41,610 but under future climate conditions, 96 00:04:41,610 --> 00:04:45,343 they are expected to have this range shift more northward. 97 00:04:47,000 --> 00:04:48,590 And so all of these species, 98 00:04:48,590 --> 00:04:51,110 there were nine selected in total, 99 00:04:51,110 --> 00:04:53,393 they were planted in 2016. 100 00:04:54,340 --> 00:04:57,130 For my research, I selected an example of 101 00:04:57,130 --> 00:04:59,120 a population enrichment planting. 102 00:04:59,120 --> 00:05:03,340 So I selected red oak and then two range expansion species, 103 00:05:03,340 --> 00:05:05,640 black birch and American chestnut 104 00:05:05,640 --> 00:05:07,590 with the goal being to kind of 105 00:05:07,590 --> 00:05:10,430 evaluate their response over the growing season 106 00:05:10,430 --> 00:05:13,500 in order to better gauge their adaptive capacity 107 00:05:13,500 --> 00:05:16,570 and performance out at this site 108 00:05:16,570 --> 00:05:19,700 in these varying gap sizes. 109 00:05:19,700 --> 00:05:22,580 And so understanding how these species are gonna respond 110 00:05:22,580 --> 00:05:25,260 to current conditions can give better insight 111 00:05:25,260 --> 00:05:27,773 into how they may behave in the future. 112 00:05:29,080 --> 00:05:31,490 And specifically I'm interested in determining 113 00:05:31,490 --> 00:05:34,110 the drought sensitivity of these species. 114 00:05:34,110 --> 00:05:37,040 And it just so happens that we experienced 115 00:05:37,040 --> 00:05:39,393 a moderate to severe trout this summer. 116 00:05:41,070 --> 00:05:42,070 As some background, 117 00:05:42,070 --> 00:05:45,070 it's important to note that there are two varying strategies 118 00:05:45,070 --> 00:05:46,670 for dealing with drought stress 119 00:05:46,670 --> 00:05:49,223 that have to do with the stomata of the plant. 120 00:05:50,130 --> 00:05:52,304 So stomata are essentially the nose and the mouth 121 00:05:52,304 --> 00:05:53,460 of the plant. 122 00:05:53,460 --> 00:05:56,260 It's where carbon assimilation is occurring, 123 00:05:56,260 --> 00:05:59,763 water vapor is lost and oxygen is released. 124 00:06:00,640 --> 00:06:02,750 And so there's two different strategies 125 00:06:02,750 --> 00:06:06,360 referred to as isohydric and anisohydric. 126 00:06:06,360 --> 00:06:08,490 And so for isohydric species, 127 00:06:08,490 --> 00:06:11,370 when there's increased atmospheric demand for water 128 00:06:11,370 --> 00:06:14,200 and declining soil water availability, 129 00:06:14,200 --> 00:06:17,330 these species have this tight stomatal regulation. 130 00:06:17,330 --> 00:06:19,370 And so they're able to close their stomata 131 00:06:19,370 --> 00:06:21,990 to kind of prevent further water loss, 132 00:06:21,990 --> 00:06:24,910 but they also are in turn 133 00:06:24,910 --> 00:06:28,930 lowering the amount of photosynthesis they're occurring 134 00:06:28,930 --> 00:06:31,013 because they've closed their stomata. 135 00:06:33,020 --> 00:06:35,410 Drought tolerant or anisohydric species 136 00:06:35,410 --> 00:06:37,260 behave in the opposite way. 137 00:06:37,260 --> 00:06:39,650 They keep their stomata open for longer periods 138 00:06:39,650 --> 00:06:40,910 during drought conditions 139 00:06:40,910 --> 00:06:44,010 and so they're photosynthesizing at higher rates 140 00:06:44,010 --> 00:06:47,270 while markedly reducing their water potential. 141 00:06:47,270 --> 00:06:50,720 And so if we were to anthropomorphize this kind of behavior, 142 00:06:50,720 --> 00:06:52,930 we would say the isohydric species kind of 143 00:06:52,930 --> 00:06:55,260 behave in a more cautious manner 144 00:06:55,260 --> 00:06:57,330 while anisohydric species kind of display 145 00:06:57,330 --> 00:06:59,263 this more daring behavior. 146 00:07:00,810 --> 00:07:02,730 And so species and gene, 147 00:07:02,730 --> 00:07:06,330 species that are considered isohydric would be, 148 00:07:06,330 --> 00:07:09,560 you know, black birch, whereas anisohydric species 149 00:07:09,560 --> 00:07:11,193 would be northern red oak. 150 00:07:13,530 --> 00:07:15,490 So building off of these strategies 151 00:07:15,490 --> 00:07:17,770 that these plants kind of exhibit, 152 00:07:17,770 --> 00:07:20,640 the ultimate goal of my research is really to determine 153 00:07:20,640 --> 00:07:23,500 the physiological response to a moderate 154 00:07:23,500 --> 00:07:26,760 and severe drought of the selected tree species 155 00:07:26,760 --> 00:07:28,270 to kinda get a better idea 156 00:07:28,270 --> 00:07:30,470 of how they're performing on the site. 157 00:07:30,470 --> 00:07:34,180 And so one method used was measuring the predawn 158 00:07:34,180 --> 00:07:36,763 and midday water potential of these plants. 159 00:07:37,950 --> 00:07:41,370 And so basically what you do for this, 160 00:07:41,370 --> 00:07:43,130 so at pre-dawn water potential, 161 00:07:43,130 --> 00:07:47,420 you go out pre-dawn and you get an assessment of the water 162 00:07:47,420 --> 00:07:49,560 status of the plant, because you know, 163 00:07:49,560 --> 00:07:51,490 they're not going through any stressful conditions. 164 00:07:51,490 --> 00:07:54,910 They're kinda at their fullest and happiest. 165 00:07:54,910 --> 00:07:57,810 And so then from there you go back in the midday, 166 00:07:57,810 --> 00:07:59,820 when things are a little bit more stressful, 167 00:07:59,820 --> 00:08:01,470 you kind of at the heat of the day 168 00:08:01,470 --> 00:08:04,040 and you measure that water potential again, 169 00:08:04,040 --> 00:08:06,900 and you can get an understanding of how far 170 00:08:06,900 --> 00:08:09,510 they've deviated from that baseline. 171 00:08:09,510 --> 00:08:12,850 And that can be indicative of how much tension 172 00:08:12,850 --> 00:08:16,210 and water stress is that plant under. 173 00:08:16,210 --> 00:08:20,480 And this has done so using a Scholander pressure bomb here. 174 00:08:20,480 --> 00:08:22,370 It just puts the plant under positive pressure 175 00:08:22,370 --> 00:08:25,523 and kinda draws that water back up through the plant. 176 00:08:28,460 --> 00:08:31,110 We also measured the photosynthetic capacity 177 00:08:31,110 --> 00:08:35,100 of the seedlings and this was done so using what is called 178 00:08:35,100 --> 00:08:38,040 an LI6400 made by LI-COR. 179 00:08:38,040 --> 00:08:40,600 It's this heavy piece of equipment that you get to 180 00:08:40,600 --> 00:08:43,690 lug up and down a mountain and clamp to the leaf 181 00:08:43,690 --> 00:08:45,430 of the plant of your choosing. 182 00:08:45,430 --> 00:08:49,000 And essentially you get a ton of different measurements 183 00:08:49,000 --> 00:08:51,130 that can kind of be indicative of 184 00:08:51,130 --> 00:08:54,763 the rate of photosynthesis that is occurring in the plant. 185 00:08:57,510 --> 00:08:59,548 And so with these measurements, 186 00:08:59,548 --> 00:09:03,010 we are expecting that this difference between 187 00:09:03,010 --> 00:09:04,450 the pre-dawn water potential 188 00:09:04,450 --> 00:09:06,440 and the midday water potential 189 00:09:06,440 --> 00:09:09,230 would be pretty high for the anisohydric species. 190 00:09:09,230 --> 00:09:12,040 So implying that that difference, 191 00:09:12,040 --> 00:09:14,720 that deviation from the baseline would be much higher 192 00:09:14,720 --> 00:09:17,150 because they're risking being, 193 00:09:17,150 --> 00:09:21,390 leaving their stomata open in order to gain more carbon. 194 00:09:21,390 --> 00:09:22,410 On the other side of this, 195 00:09:22,410 --> 00:09:24,291 we would expect that the isohydric species 196 00:09:24,291 --> 00:09:26,830 would have less of a difference between pre-dawn 197 00:09:26,830 --> 00:09:29,030 and midday water potential, because again, 198 00:09:29,030 --> 00:09:31,440 they have that tighter stomatal regulation. 199 00:09:31,440 --> 00:09:33,170 And so they're keeping their stomata closed 200 00:09:33,170 --> 00:09:35,023 during periods of drought. 201 00:09:36,430 --> 00:09:39,320 Regarding photosynthesis, we would expect that 202 00:09:39,320 --> 00:09:40,880 the anisohydric species, 203 00:09:40,880 --> 00:09:44,170 so again those drought tolerant species like red oak 204 00:09:44,170 --> 00:09:46,850 are going to have high rates of photosynthesis 205 00:09:46,850 --> 00:09:49,440 during periods of drought stress. 206 00:09:49,440 --> 00:09:51,350 And on the other end of that, 207 00:09:51,350 --> 00:09:55,000 we would expect the isohydric species like black birch 208 00:09:55,000 --> 00:09:57,470 and potentially American chestnut 209 00:09:57,470 --> 00:10:00,240 to have lower photosynthetic capacity, 210 00:10:00,240 --> 00:10:02,230 because again, they're shutting their stomata 211 00:10:02,230 --> 00:10:05,423 during these periods of water stress. 212 00:10:07,270 --> 00:10:10,470 So here is what we found in terms of water potential. 213 00:10:10,470 --> 00:10:14,026 And just for some context to kinda explain this figure, 214 00:10:14,026 --> 00:10:16,980 we did four different sampling periods 215 00:10:16,980 --> 00:10:17,920 over the growing season. 216 00:10:17,920 --> 00:10:21,680 So we had June, mid or early June, mid June, 217 00:10:21,680 --> 00:10:22,960 July and August. 218 00:10:22,960 --> 00:10:24,210 And during this period, 219 00:10:24,210 --> 00:10:28,600 we had an abnormally dry period, a moderate drought, 220 00:10:28,600 --> 00:10:31,693 a severe drought and another moderate drought. 221 00:10:33,870 --> 00:10:37,070 And so what we really saw is that the, 222 00:10:37,070 --> 00:10:39,390 between species water potential, 223 00:10:39,390 --> 00:10:42,310 that difference between that pre-dawn water potential 224 00:10:42,310 --> 00:10:44,210 and midday water potential 225 00:10:44,210 --> 00:10:46,640 did not really vary between species. 226 00:10:46,640 --> 00:10:49,050 They were all pretty similar in their response. 227 00:10:49,050 --> 00:10:50,930 However, we did see that the difference 228 00:10:50,930 --> 00:10:53,430 between pre-dawn and midday water potentials 229 00:10:53,430 --> 00:10:56,480 decreased in all species in response to 230 00:10:56,480 --> 00:10:58,893 these drying soil conditions, 231 00:11:00,700 --> 00:11:02,500 especially during these periods of severe 232 00:11:02,500 --> 00:11:05,603 and moderate drought in July and August. 233 00:11:06,730 --> 00:11:10,230 Looking at the photosynthetic capacity, 234 00:11:10,230 --> 00:11:12,830 you can see here for black birch, 235 00:11:12,830 --> 00:11:17,240 we had low photosynthetic rates during that severe 236 00:11:17,240 --> 00:11:21,090 and moderate drought in July and August. 237 00:11:21,090 --> 00:11:22,950 So they kind of shut down their stomata 238 00:11:22,950 --> 00:11:25,290 during these periods of extreme water stress. 239 00:11:25,290 --> 00:11:26,630 And so this is again, 240 00:11:26,630 --> 00:11:28,962 exhibiting that isohydric behavior 241 00:11:28,962 --> 00:11:31,610 that we expected to see. 242 00:11:31,610 --> 00:11:32,760 For American chestnut, 243 00:11:32,760 --> 00:11:35,840 you can kinda see that this species maintained 244 00:11:35,840 --> 00:11:38,440 a pretty consistent photosynthetic rate 245 00:11:38,440 --> 00:11:40,140 throughout the growing season. 246 00:11:40,140 --> 00:11:44,140 August in June photosynthetic rates did vary significantly, 247 00:11:44,140 --> 00:11:47,430 but other than that, they were pretty steady throughout. 248 00:11:47,430 --> 00:11:51,503 And so this is exhibiting a moderate anisohydric behavior. 249 00:11:53,510 --> 00:11:56,310 All right, and here's the star of the show red oak. 250 00:11:56,310 --> 00:11:58,210 So red oak in June 251 00:11:58,210 --> 00:12:01,290 had pretty consistent photosynthetic rates, 252 00:12:01,290 --> 00:12:03,750 but then during those periods of severe 253 00:12:03,750 --> 00:12:07,170 and moderate drought in July and August, 254 00:12:07,170 --> 00:12:10,270 you can see that they had these high increased 255 00:12:10,270 --> 00:12:13,250 photosynthetic rates in each of these months. 256 00:12:13,250 --> 00:12:15,490 And so they are strongly exhibiting 257 00:12:15,490 --> 00:12:17,983 this anisohydric behavior. 258 00:12:19,570 --> 00:12:23,620 When comparing across species for the month of June, 259 00:12:23,620 --> 00:12:26,710 where we had the abnormal dry period 260 00:12:26,710 --> 00:12:29,800 and a slight moderate drought, 261 00:12:29,800 --> 00:12:32,730 red oak had greater photosynthetic rates 262 00:12:32,730 --> 00:12:34,680 than American chestnut, 263 00:12:34,680 --> 00:12:36,860 not so much against black birch. 264 00:12:36,860 --> 00:12:40,460 In July red oak again had greater photosynthetic rates 265 00:12:40,460 --> 00:12:43,200 than both American chestnut and black birch. 266 00:12:43,200 --> 00:12:45,290 And then in August again, 267 00:12:45,290 --> 00:12:47,880 red oak had the highest photosynthetic rates 268 00:12:47,880 --> 00:12:49,940 compared to the other two species. 269 00:12:49,940 --> 00:12:52,120 And so it's just really performing well 270 00:12:52,120 --> 00:12:54,313 during these periods of high stress. 271 00:12:55,190 --> 00:12:58,090 So again, we were expecting to see that 272 00:12:58,090 --> 00:13:00,430 that difference between the pre-dawn water potential 273 00:13:00,430 --> 00:13:02,770 and midday, that would be highest 274 00:13:02,770 --> 00:13:04,500 for the anisohydric species 275 00:13:04,500 --> 00:13:07,200 and lowest for the isohydric species. 276 00:13:07,200 --> 00:13:09,410 And that photosynthetic rates would be high 277 00:13:09,410 --> 00:13:12,170 for the anisohydric species, red oak 278 00:13:12,170 --> 00:13:16,060 and lowest for the isohydric species, black birch. 279 00:13:16,060 --> 00:13:18,750 And so what did we actually see? 280 00:13:18,750 --> 00:13:22,880 Well, we saw that actually for the delta water potential, 281 00:13:22,880 --> 00:13:26,440 so again, that change between that baseline 282 00:13:26,440 --> 00:13:29,050 and the most stressful time of day 283 00:13:29,050 --> 00:13:31,320 was actually high for both isohydric 284 00:13:31,320 --> 00:13:33,210 and anisohydric species. 285 00:13:33,210 --> 00:13:36,500 So black birch and red oak and American chestnut 286 00:13:36,500 --> 00:13:41,163 all had very similar differences in their water potential. 287 00:13:42,170 --> 00:13:45,730 We also saw that photosynthetic capacity 288 00:13:45,730 --> 00:13:47,230 was what we expected. 289 00:13:47,230 --> 00:13:50,000 So very high for those anisohydric species 290 00:13:50,000 --> 00:13:51,310 that keep their stomata open 291 00:13:51,310 --> 00:13:52,880 during periods of stress 292 00:13:52,880 --> 00:13:55,200 and lower for the isohydric species, 293 00:13:55,200 --> 00:13:57,330 that again, behave in a little bit more 294 00:13:57,330 --> 00:13:59,083 of a cautious manner. 295 00:14:00,610 --> 00:14:03,070 So really the big takeaways from this is that 296 00:14:03,070 --> 00:14:06,640 as we anticipate these changing climate regimes, 297 00:14:06,640 --> 00:14:10,200 these future adapt to species do seem to be responding 298 00:14:10,200 --> 00:14:12,053 in a way that is pretty promising. 299 00:14:13,360 --> 00:14:15,210 From previous studies, we've noticed that there is 300 00:14:15,210 --> 00:14:19,490 higher survivorship for the anisohydric red oak, 301 00:14:19,490 --> 00:14:21,790 however these do exhibit lower growth, 302 00:14:21,790 --> 00:14:24,593 so they're a little bit slower in their establishment. 303 00:14:25,863 --> 00:14:29,210 But on the other end of this red oak and American chestnut, 304 00:14:29,210 --> 00:14:33,100 so this, you know, typical anisohydric species 305 00:14:33,100 --> 00:14:35,620 and a moderate anisohydric species 306 00:14:35,620 --> 00:14:38,940 are expected to tolerate these moderate to severe droughts, 307 00:14:38,940 --> 00:14:42,010 which are expected to increase in frequency. 308 00:14:42,010 --> 00:14:43,610 And so although there is some risk 309 00:14:43,610 --> 00:14:46,530 in maintaining that open stomata during periods of drought, 310 00:14:46,530 --> 00:14:49,080 there's also a huge gain regarding 311 00:14:49,080 --> 00:14:51,310 this establishment for these species 312 00:14:51,310 --> 00:14:54,793 and that could give them a competitive edge in the future. 313 00:14:55,860 --> 00:14:58,570 And although black birch is expected to have suitable 314 00:14:58,570 --> 00:15:02,240 habitat further north based on these changing temperatures, 315 00:15:02,240 --> 00:15:04,900 these species still do prefer moist climates 316 00:15:04,900 --> 00:15:09,443 and so they may struggle with persistent severe drought. 317 00:15:12,320 --> 00:15:13,980 Taking this a step further, 318 00:15:13,980 --> 00:15:17,230 I'm really interested in understanding these mortality 319 00:15:17,230 --> 00:15:20,120 thresholds for these future adapted species 320 00:15:20,120 --> 00:15:22,810 that are expected to have either a population expansion 321 00:15:22,810 --> 00:15:25,000 or a range expansion. 322 00:15:25,000 --> 00:15:27,900 And so I'm gonna be exposing the species 323 00:15:27,900 --> 00:15:30,570 to a precipitation exclusion 324 00:15:30,570 --> 00:15:32,100 with the ultimate goal being, you know, 325 00:15:32,100 --> 00:15:35,040 how much water stress can these species experience 326 00:15:35,040 --> 00:15:37,943 before we start to see declines in survival. 327 00:15:38,890 --> 00:15:40,880 Beyond future adapted species, 328 00:15:40,880 --> 00:15:45,350 I'm also very interested in determining how the resistance 329 00:15:45,350 --> 00:15:48,070 and resilience treatments are going to impact 330 00:15:48,070 --> 00:15:51,230 overstory species in terms of their water relations. 331 00:15:51,230 --> 00:15:54,240 And this will be done so using carbon stable isotopes 332 00:15:54,240 --> 00:15:57,730 to better gauge how water stress is occurring 333 00:15:57,730 --> 00:16:00,530 based on civil cultural treatments. 334 00:16:00,530 --> 00:16:01,363 And with that, 335 00:16:01,363 --> 00:16:04,691 I just want to acknowledge all of the amazing people 336 00:16:04,691 --> 00:16:07,380 that have helped me with my past project, 337 00:16:07,380 --> 00:16:10,500 as well as these future projects that I touched on. 338 00:16:10,500 --> 00:16:13,170 I'm just very fortunate to have such an amazing 339 00:16:13,170 --> 00:16:16,569 and supportive lab and group of people to work with. 340 00:16:16,569 --> 00:16:20,453 And so I will take any and all questions. 341 00:16:21,320 --> 00:16:25,080 - Thank you so much for that informative talk. 342 00:16:25,080 --> 00:16:27,529 - [Jerry] I have a question, Jerry in New York. 343 00:16:27,529 --> 00:16:32,529 Do you think that these data are really good example 344 00:16:34,360 --> 00:16:38,110 of why it would be beneficial to re-introduce transgenic 345 00:16:38,110 --> 00:16:41,563 chestnut to the landscape for climate change mitigation? 346 00:16:43,280 --> 00:16:46,070 - Well, so we unfortunately 347 00:16:46,070 --> 00:16:49,530 didn't have the transgenic chestnut planted on the site. 348 00:16:49,530 --> 00:16:51,700 Most of these were the hybrids. 349 00:16:51,700 --> 00:16:53,880 but there are studies that are going on 350 00:16:53,880 --> 00:16:55,470 with the transgenic chestnut 351 00:16:55,470 --> 00:16:57,240 that may be a little bit more useful 352 00:16:57,240 --> 00:16:59,230 to provide that information. 353 00:16:59,230 --> 00:17:02,020 but I definitely think that these kinds of methods 354 00:17:02,020 --> 00:17:04,640 would be useful and beneficial to understand 355 00:17:04,640 --> 00:17:06,830 like how it may perform at a site. 356 00:17:06,830 --> 00:17:09,720 So I think carrying forward, it would be worth, 357 00:17:09,720 --> 00:17:12,230 you know, doing all of these measurements 358 00:17:12,230 --> 00:17:16,260 in areas where we do have planted transgenic chestnut. 359 00:17:16,260 --> 00:17:18,160 Hopefully that answered your question. 360 00:17:19,180 --> 00:17:20,110 But I would love to. 361 00:17:20,110 --> 00:17:21,260 If I had the opportunity, 362 00:17:21,260 --> 00:17:25,310 I would 100% do a study with the transgenic chestnut. 363 00:17:25,310 --> 00:17:27,803 I just think it's a really, really cool project. 364 00:17:35,370 --> 00:17:37,190 It looks like there is a question in the chat. 365 00:17:37,190 --> 00:17:39,920 It says, I'm wondering which other future adapted species 366 00:17:39,920 --> 00:17:41,850 for this region you're interested in exploring 367 00:17:41,850 --> 00:17:43,453 mortality thresholds for. 368 00:17:45,660 --> 00:17:49,140 Yeah, so for this upcoming summer, 369 00:17:49,140 --> 00:17:52,450 I'm gonna be measuring black cherry, bitternut hickory, 370 00:17:52,450 --> 00:17:55,520 basswood, red oak, 371 00:17:55,520 --> 00:17:59,983 and why am I blanking on the last one? 372 00:18:01,550 --> 00:18:02,690 Black birch, yeah. 373 00:18:02,690 --> 00:18:05,560 So those are the ones that we're focusing in on. 374 00:18:05,560 --> 00:18:07,320 I'm especially interested in bitternut hickory, 375 00:18:07,320 --> 00:18:10,310 just because it is a pretty far rain shift 376 00:18:10,310 --> 00:18:13,030 and so I'm interested to see kinda how it's gonna be doing 377 00:18:13,030 --> 00:18:15,130 in our rich Northern hardwood, 378 00:18:15,130 --> 00:18:19,100 that's a little bit further north than it's expected to be. 379 00:18:19,100 --> 00:18:22,760 But there's also at the project 380 00:18:22,760 --> 00:18:25,150 that I didn't get to measure, there's white pine. 381 00:18:25,150 --> 00:18:26,893 We have Eastern hemlock, 382 00:18:29,570 --> 00:18:30,530 big tooth aspen. 383 00:18:30,530 --> 00:18:33,420 So there's a lot of different species that are being planted 384 00:18:33,420 --> 00:18:34,470 that we're assessing. 385 00:18:34,470 --> 00:18:36,620 And so those that are at the Second College Grant, 386 00:18:36,620 --> 00:18:40,440 we do have long-term, for the last five years measurements, 387 00:18:40,440 --> 00:18:43,610 on growth and survivorship, that's gonna be carried forward. 388 00:18:43,610 --> 00:18:46,110 So hopefully that answered your question Madeline. 389 00:18:47,005 --> 00:18:49,086 - Hi Al, nice presentation. 390 00:18:49,086 --> 00:18:51,600 I'm curious, did you see any patterns 391 00:18:51,600 --> 00:18:53,270 in the pre-dawn water potentials 392 00:18:53,270 --> 00:18:56,540 over the course of the season for any of your species? 393 00:18:56,540 --> 00:18:59,370 - So the pre-dawns were all pretty consistent. 394 00:18:59,370 --> 00:19:00,830 They definitely started, you know, 395 00:19:00,830 --> 00:19:05,400 they were starting at a more negative water potential 396 00:19:05,400 --> 00:19:07,610 in those severe to moderate droughts. 397 00:19:07,610 --> 00:19:08,620 But for the most part, 398 00:19:08,620 --> 00:19:12,670 like across species, they were all pretty consistent. 399 00:19:12,670 --> 00:19:15,940 But I'm hoping, you know, doing this precipitation exclusion 400 00:19:15,940 --> 00:19:17,500 and like really stressing them out, 401 00:19:17,500 --> 00:19:20,720 I'll start to see some more clear trends. 402 00:19:20,720 --> 00:19:23,160 - Cool, thank you. - Yeah, of course. 403 00:19:23,160 --> 00:19:25,100 So is there a wide genetic range 404 00:19:25,100 --> 00:19:27,010 within species for these traits? 405 00:19:27,010 --> 00:19:28,770 So we were pretty limited 406 00:19:28,770 --> 00:19:32,950 since the Northeast does not have a lot of plantings 407 00:19:32,950 --> 00:19:35,380 or just like, we just don't really plant 408 00:19:35,380 --> 00:19:38,080 whenever we do civil culture or forest management, 409 00:19:38,080 --> 00:19:40,900 it's just not a big part of our management here, 410 00:19:40,900 --> 00:19:41,733 since we don't have to, 411 00:19:41,733 --> 00:19:43,893 we have so much advanced regeneration. 412 00:19:44,910 --> 00:19:46,000 So we were pretty limited 413 00:19:46,000 --> 00:19:47,610 in where we could get our seed source. 414 00:19:47,610 --> 00:19:50,600 And so there isn't a ton of genetic... 415 00:19:51,700 --> 00:19:53,700 We didn't do a lot of provenance studies with this. 416 00:19:53,700 --> 00:19:58,700 So hopefully in the future we can, you know, 417 00:19:58,820 --> 00:20:00,810 have some more provenance studies, 418 00:20:00,810 --> 00:20:04,833 but that wasn't a big part of these plantings. 419 00:20:05,790 --> 00:20:07,620 Hey Tom, how's it going? 420 00:20:07,620 --> 00:20:09,694 - Hey Al good to see you. - Good to see you too. 421 00:20:09,694 --> 00:20:14,080 - Great presentation and really, really good work. 422 00:20:14,080 --> 00:20:17,440 So I've got a question that may be unfair to you, 423 00:20:17,440 --> 00:20:20,010 but I'm wondering if there's a relation. 424 00:20:20,010 --> 00:20:21,140 Well, let me back up, 425 00:20:21,140 --> 00:20:24,933 both of your anisohydric species are rain porous. 426 00:20:25,860 --> 00:20:27,380 Is there a relationship relationship 427 00:20:27,380 --> 00:20:28,690 between the vessel structure 428 00:20:28,690 --> 00:20:30,693 and the behavior of the stomata? 429 00:20:30,693 --> 00:20:32,053 This this is new to me. 430 00:20:33,180 --> 00:20:36,340 - Yeah, so typically diffuse porous species 431 00:20:36,340 --> 00:20:41,340 kind of lean more towards the isohydric range. 432 00:20:41,410 --> 00:20:42,630 I'm not 100, 433 00:20:42,630 --> 00:20:45,970 I can't give you an answer exactly why that is, 434 00:20:45,970 --> 00:20:47,030 but that does come into play. 435 00:20:47,030 --> 00:20:50,180 So those functional traits do have a role in terms of, 436 00:20:50,180 --> 00:20:53,330 you know, the drought response. 437 00:20:53,330 --> 00:20:55,250 And there's actually a paper that was just released 438 00:20:55,250 --> 00:20:56,800 that has a bunch of different traits 439 00:20:56,800 --> 00:20:59,810 that they're finding that kind of those functional traits 440 00:20:59,810 --> 00:21:01,266 that divide them into isohydric and anisohydric. 441 00:21:01,266 --> 00:21:04,773 And so that is, that is one of those. 442 00:21:05,810 --> 00:21:06,730 - Yeah, thanks a lot. 443 00:21:06,730 --> 00:21:07,563 This is new to me. 444 00:21:07,563 --> 00:21:08,890 This is just fascinating. 445 00:21:08,890 --> 00:21:10,080 So thank you. 446 00:21:10,080 --> 00:21:11,003 - Yeah, of course. 447 00:21:12,350 --> 00:21:14,240 - Al, that was a great presentation 448 00:21:14,240 --> 00:21:15,820 and really interesting to me. 449 00:21:15,820 --> 00:21:19,540 So I'm curious if you think as age increases 450 00:21:19,540 --> 00:21:21,520 with those species, 451 00:21:21,520 --> 00:21:26,193 do those characteristics change in the plant? 452 00:21:28,070 --> 00:21:31,060 - So I think they still behave pretty similarly, 453 00:21:31,060 --> 00:21:33,350 but you definitely I think see more extremes 454 00:21:33,350 --> 00:21:35,200 probably whenever they're younger, 455 00:21:35,200 --> 00:21:38,500 just because things are a little bit more competitive. 456 00:21:38,500 --> 00:21:41,450 But one thing that I am looking to do, 457 00:21:41,450 --> 00:21:43,440 so in all three of the treatments, 458 00:21:43,440 --> 00:21:45,760 the resistance, resilience, and transition, 459 00:21:45,760 --> 00:21:48,800 I'm gonna be taking tree cores of overstory trees. 460 00:21:48,800 --> 00:21:50,703 And so that can give you, 461 00:21:51,740 --> 00:21:53,530 when you do carbon stable isotopes on those, 462 00:21:53,530 --> 00:21:56,880 you can get the relation of C-13 to C-12, 463 00:21:56,880 --> 00:21:58,400 which is kind of what they're fixing. 464 00:21:58,400 --> 00:22:02,540 And so to make a complicated topic less complicated, 465 00:22:02,540 --> 00:22:05,440 so basically if they're closing their stomata more 466 00:22:05,440 --> 00:22:07,510 because they're really stressed, 467 00:22:07,510 --> 00:22:10,840 they're gonna deplete that like lighter C-12, 468 00:22:10,840 --> 00:22:12,450 and use more C-13. 469 00:22:12,450 --> 00:22:16,620 So if you have a higher ratio of C-13 to C-12, 470 00:22:16,620 --> 00:22:19,430 it tells you that the plant was more stressed 471 00:22:19,430 --> 00:22:21,237 and closed their stomata more. 472 00:22:21,237 --> 00:22:24,586 Hopefully this is making sense. (laughs) 473 00:22:24,586 --> 00:22:26,340 - Yeah, it is making sense, 474 00:22:26,340 --> 00:22:27,901 but there's a lot of things going on there 475 00:22:27,901 --> 00:22:29,710 and it's really interesting. - Yes, no, absolutely. 476 00:22:29,710 --> 00:22:31,100 - You know black birch for instance, 477 00:22:31,100 --> 00:22:33,840 seems to be really doing well you know, 478 00:22:33,840 --> 00:22:35,980 in Southern New England like Connecticut. 479 00:22:35,980 --> 00:22:38,750 And so you think of it as being a species 480 00:22:38,750 --> 00:22:41,800 that that may be climate resilient, 481 00:22:41,800 --> 00:22:44,135 but yet what you're finding is that certainly 482 00:22:44,135 --> 00:22:47,720 as you're moving north, it may not be as resilient. 483 00:22:47,720 --> 00:22:49,440 - Well, so that's also one of the benefits 484 00:22:49,440 --> 00:22:52,410 of the drought study is to kind of see what its limits are. 485 00:22:52,410 --> 00:22:54,950 Because sometimes being isohydric 486 00:22:54,950 --> 00:22:56,890 can actually be beneficial 487 00:22:56,890 --> 00:22:58,440 where you're being a little bit more cautious, 488 00:22:58,440 --> 00:23:02,290 especially if we're not gonna have huge, severe droughts. 489 00:23:02,290 --> 00:23:05,010 So playing it a little bit more cautiously can be hugely 490 00:23:05,010 --> 00:23:08,840 beneficial in like, you know, shorter term droughts. 491 00:23:08,840 --> 00:23:11,810 Whereas like, if you are leaving your stomata open, 492 00:23:11,810 --> 00:23:15,130 if you're depleting your water and water doesn't come for, 493 00:23:15,130 --> 00:23:16,630 you know, another month, 494 00:23:16,630 --> 00:23:20,280 you actually may have higher rates of decline. 495 00:23:20,280 --> 00:23:23,122 So it's very complicated and kinda hard to tease out, 496 00:23:23,122 --> 00:23:26,870 but I'm hoping through both of those kinds of lenses, 497 00:23:26,870 --> 00:23:30,010 I can have a clearer image of how these seedlings 498 00:23:30,010 --> 00:23:32,950 are gonna do outside of their typical range. 499 00:23:32,950 --> 00:23:33,910 - Well I like the lens. 500 00:23:33,910 --> 00:23:36,050 So it's very cool, good luck. 501 00:23:36,050 --> 00:23:37,050 - Thank you so much. 502 00:23:38,120 --> 00:23:39,780 - [Jerry] Yeah, I have another question. 503 00:23:39,780 --> 00:23:44,130 I'm fascinated by the carbon-13 and carbon-14 variants 504 00:23:44,130 --> 00:23:45,763 that you've mentioned just now. 505 00:23:46,720 --> 00:23:49,830 Could you conceivably go out and collect cores 506 00:23:49,830 --> 00:23:52,120 and then take those cores to a lab somewhere 507 00:23:52,120 --> 00:23:56,827 and get that difference analyzed by year? 508 00:23:56,827 --> 00:23:58,520 Yeah, I see you nodding your head. 509 00:23:58,520 --> 00:23:59,860 Yeah, yeah, no, exactly. 510 00:23:59,860 --> 00:24:03,909 So it's gonna be it's C-13 versus C-12 511 00:24:03,909 --> 00:24:06,120 for what I'm looking at, but you, yeah, 512 00:24:06,120 --> 00:24:07,950 so that's what you basically go out and do 513 00:24:07,950 --> 00:24:10,110 is you go out and core these trees. 514 00:24:10,110 --> 00:24:12,610 And I'm gonna be looking at the different treatments, 515 00:24:12,610 --> 00:24:14,960 so like the matrix thinning versus the gaps 516 00:24:14,960 --> 00:24:16,330 versus just control, 517 00:24:16,330 --> 00:24:18,590 and then you send that to a lab to get analyzed. 518 00:24:18,590 --> 00:24:21,029 So that's definitely- - How difficult, 519 00:24:21,029 --> 00:24:22,579 How difficult is that analysis? 520 00:24:23,599 --> 00:24:25,870 - Well, I'm paying somebody, 521 00:24:25,870 --> 00:24:27,850 so I basically just core the tree 522 00:24:27,850 --> 00:24:29,760 and then you grind down the samples 523 00:24:29,760 --> 00:24:32,720 into these fine little balls that you ship off. 524 00:24:32,720 --> 00:24:33,990 So I have never actually 525 00:24:33,990 --> 00:24:35,421 performed that analysis. - And so are you doing 526 00:24:35,421 --> 00:24:36,902 that by tree ring, 527 00:24:36,902 --> 00:24:38,970 you know, by age? - Yeah. 528 00:24:38,970 --> 00:24:39,803 - Yeah. - Yeah. 529 00:24:39,803 --> 00:24:41,139 - [Jerry] Okay, how much does that cost? 530 00:24:41,139 --> 00:24:42,445 - Ooh, that's a good one. 531 00:24:42,445 --> 00:24:43,882 - It's a... - It's fascinating. 532 00:24:43,882 --> 00:24:45,700 I'd like to maybe try some of that. 533 00:24:45,700 --> 00:24:47,840 - I don't know, off the top of my head, 534 00:24:47,840 --> 00:24:50,140 how much it costs and it depends on the lab you send it to. 535 00:24:50,140 --> 00:24:52,790 So there is a really great person at K State 536 00:24:52,790 --> 00:24:55,130 who does a lot of carbon stable isotope work, 537 00:24:55,130 --> 00:24:57,270 but I think there's other places in New England. 538 00:24:57,270 --> 00:24:59,570 But if you email me, I'd be happy to, 539 00:24:59,570 --> 00:25:01,010 you know, send you some contacts, 540 00:25:01,010 --> 00:25:03,400 if this is something you're interested in doing. 541 00:25:03,400 --> 00:25:04,360 - [Jerry] Well, I'd have to figure out 542 00:25:04,360 --> 00:25:05,760 how to put a study together on that. 543 00:25:05,760 --> 00:25:08,810 But certainly the impact of climate change 544 00:25:08,810 --> 00:25:13,390 and drought here in New York is where I am, is huge. 545 00:25:13,390 --> 00:25:14,893 - Yeah, no definitely. - Yeah.