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  • [Birds chirping.]

  • People come here to the Smokies during a particular two weeks in June

  • to see synchronous fireflies and this year that happened in May,

  • well before the event that was going to start on June the 7th,

  • so when people actually got here on the 7th, not only had the

  • peak passed, but the firefly display was completely finished.

  • Can we say that was because of climate change? No. But if we look at the trend

  • over the years, we can see that some of these, you know,

  • over the years, the events are occurring, you know, earlier than they used to.

  • [Climate Change Song- "Wildwood Flower" Tune]

  • Phenology is the time of year

  • that certain events happen in the biological world.

  • So, when things flower and when they turn to fruit

  • and when the leaves turn green on a plant, come out, and then turn color

  • perhaps in fall, those are all phenological events.

  • When migratory birds come back from the tropics,

  • start singing, set up territories, when they have their nests

  • and when they depart, those are all phenological events.

  • [Birds chirping.]

  • And it can really be at the community level or the species level and this is

  • important because there's a lot of synchrony between species and communities

  • and if climate change happens too rapidly or if other issues involving

  • climate--temperature and moisture--it could lead to impacts

  • which we need to be aware of.

  • Phenology in this park really started with Arthur Stoopka who was a

  • 1938 appointee to this park as a naturalist

  • and later biologist. And he started recording times

  • when various plants bloomed in different sites. And I don't mean a few times,

  • he made 18,000 observations having to do with all sorts of different things,

  • and many of those are based on phenology. And we have that in a database

  • so we can now search, and that gives us a good basis for looking at changes, particularly

  • in plants and arrival of birds.

  • We've had plots out now for 10 years off and on looking at the same exact

  • four-meter-square area, three plots in a site and then

  • multiple sites at different elevations. And there we actually do counts

  • of individual flowers in full bloom. In some cases,

  • the same species on an elevational transect.

  • One other thing that we have been recording at the

  • Great Smoky Mountains Institute at Tremont, over in the Tennessee side of

  • the park, and the teachers there and the students have been

  • recording the first time they hear wood frogs sing, or the first

  • time they see such and such a plant bloom or the first time they see a dragonfly

  • and many of those species have been

  • showing earlier phenology over the past couple of decades.

  • The problem with that kind of data--it's useful--but

  • we want to collect data at very specific locations

  • repeating them over and over again so that we can figure out

  • not just the first one, but when the peak arrival is or when the peak bloom is.

  • [Indistinct chatter.]

  • You have to go out and you have to follow an individual tree or an

  • individual set of plants or go to the same place

  • and listen for birds over the period of time you might expect

  • them to come back, but that's data for just one year.

  • So, in order to look for trends--is it getting earlier,

  • are they coming later?--you would need to go back

  • and do the same thing with the same plants at the same site

  • over and over again for several years and

  • there's a lot of variation from one year to the next. So, you'd want

  • to have several years to average it out, to see a trend.

  • So the question of identifying what's

  • causing changes in phenology that people are observing over long periods of time,

  • especially in one particular location, is a tricky question

  • because first you have to be able to establish

  • that temperature changes or changes in precipitation are what's driving that.

  • And then you have to understand what's driving those changes in temperature or

  • precipitation at that one place. Because in a lot of different places, temperature

  • change can be because of urbanization or deforestation

  • and that can cause warming of an environment.

  • Or if you go from an agricultural environment to a primarily forested environment,

  • you can get cooling that's just caused by local effects rather than

  • human-caused global climate change.

  • But what allows us to understand

  • that phenological shifts more broadly

  • are attributed to climate change is that we're seeing similar patterns in lots

  • of different locations across the world. So that local climate

  • change can't be the driver of all of them.

  • [Birds chirping.]

  • I think of the Smokies like a giant English muffin and we have all these little nooks

  • and crannies, you know, when you toast an English muffin it doesn't brown evenly.

  • Well, the Smokies is like that with temperature. So, to really sample in the Smokies

  • you need to really get in to all those nooks and crannies and we just don't have enough park staff to do that.

  • So with citizen scientists and carefully planned out locations

  • of plots, we can actually get people to adopt a plot

  • and go in and help us to collect this data about each little nook and cranny

  • that we're interested in that we just couldn't do as park rangers.

  • So again, we're hoping that people will develop a relationship and actually start to

  • notice changes that we as park staff might not see because

  • they're out there maybe on a weekly basis checking the same spot.

  • They're going to really get to know that location and document those changes

  • as opposed to just being anecdotal changes.

  • [Female data collector: "Seven point two."] [Male data collector: "Seven point two."]

  • [Young girl: "We got it! Yes!...We caught one!"]

  • The reason citizen science is such a great tool, for one,

  • people like contributing, they like feeling like they're helping.

  • If you give people an opportunity to help collect data that you truly are using,

  • and that's kind of the key, it's not citizen science if that data never gets

  • put into a database, never gets looked at, but if you're truly using that data

  • and people have a way to contribute to that data,

  • they feel good about it, they like doing it, you know, they get that personal connection

  • both with the park and with whatever it is they're studying. And it just,

  • it's a total win-win situation.

  • [Park Ranger: "We're going to be tracking this tree over time, so for this year, it's a five."]

  • I feel that the phenology study in particular has made the issue of climate change more

  • accessible because it's a way for people to

  • relate to it personally. You know, people around here,

  • for instance, are tuned in to spring wildflowers and

  • the leaves changing in the fall because our economy is really tied to the tourism

  • that revolves around some of those events, so they're things that people notice anyway,

  • but if we're letting them know about some of these possible mismatches,

  • it's not just that the flowers are blooming two weeks earlier, but there's

  • this whole kind of trickledown effect that you get if the flowers bloom earlier

  • and their pollinators aren't there and the birds who eat those pollinators

  • and these things that can go out of synchronicity and out of whack.

  • That there's this whole chain of events and phenology is just

  • beautiful for illustrating that, and it's happening

  • now, it's not happening conceptually 10 years or 20 years in the future.

  • [Climate Change Song-"Wildwood Flower" Tune]

  • [Climate change is real, it's happening around the world today]

  • [It's effects are measured, seen and felt in many different ways]

  • [And no matter what we'd like to hope, pretend or just ignore]

  • [We've got lots to learn and do, hey now that's what this song is for.]

[Birds chirping.]

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B1 中級

國家公園的氣候變化科學。追蹤自然事件的時間 (The Science of Climate Change in National Parks: Tracking the Timing of Natural Events)

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    cyrain 發佈於 2021 年 01 月 14 日
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