 Good afternoon and welcome to likeable science here on Think Tech Hawaii. I'm your host Ethan Allen. Thanks for joining us today while we explore science and why science is a vital and interesting part of everyone's life. Today I have in the studio with me Dr. Leland Worden. Welcome Leland. Thank you. Good to have you here. Leland is a postdoctoral fellow at Lyon Arboretum, part of the University of Hawaii at Manawa and he is a restoration ecologist I guess is sort of your title. So tell us what a restoration ecologist does. Yeah so restoration ecology is a really enormous field but the concept is that you're coming in and basically restoring an ecosystem that has been damaged, degraded or destroyed. So the idea is to try to bring back function that can be species or also just ecosystem services of that ecosystem. And specifically I work on tropical forest restoration in both wet and dry forests. Great I mean that's got to be challenging because the more the more we learn about ecosystems the more we realize these are incredibly complex systems with thousands on thousands of interacting parts some of which are absolutely crucial to the functioning of other parts right? Yeah absolutely so it's it's basically just trying to put all these pieces together and one of the really cool things about restoration is that there's so many steps involved that you really have to take a holistic approach where you understand so how a seed germinates and whether or not that species is suitable for the soil type and there's a lot of things but it's true it's a it's very complex and but really fun to work in because you get to do a lot of different things. True and it must be a real time element too because when you're restoring a particular trees and things you can't bring in adult trees you do have to bring in the seeds or seedlings and start start with them and know that it's still going to be decades before you've really restored that ecosystem right? Right yeah and it can be much faster in certain systems but yes in forests it's we'd like to think in terms of decades and centuries rather than just a couple years yeah. And you've been you've said you did your graduate work in Minnesota? Yeah the University of Minnesota in cities. Excellent but you were at that point working down in Costa Rica a lot? Yeah so I specifically for my doctorate worked on restoring tropical dry forests in northwestern Costa Rica and this pretty incredible conservation area called the Ariade Conservacion Guanacaste. I think we have an image right? Yeah so the first slide shows in northwestern Costa Rica basically the green segment is the protected area and I worked in kind of the north or in southwestern corner of that this little anvil in the corner called Horizonte which is the experimental forest. What's really incredible about this system is that about 80% of the forest has naturally regenerated after just removing some pressures such as unnatural grazers as cows and that actually restricting non just naturally occurring fires. But there are areas about 20% of this protected area that really needs to take an active restoration approach by planting trees because of soil degradation and other things. So that was what I focused on specifically. Excellent now a lot of people when they think of tropical forests they think of rainforests because that's sort of that sort of the image we all got from movies and books and all of these heavily green monstrous canopies dripping moisture down on us. But there are tropical dry forests. Yeah so dry forests is this really incredible ecosystem it's also almost 50% of all tropical forests or dry forests globally. So in a tropical dry forest half of the year typically although it's a range of kind of six to eight months is completely dry so no rain whatsoever and then that results in there being a lot of deciduous species generally although there's a whole range of dry forests too. But it's very different like in the wet season it can actually look really very similar to a wet forest but sometimes in the dry season especially where I work it looks like a desert. So also in Hawaii there's quite a few dry forests but people typically you're right don't think about the fact that this is a really critically important ecosystem. Right and it's important because these these are part you know the ecosystems don't exist in isolation right they're all connected to the ecosystems next to them and all and so everything that's happening in one is impacting the other either species are flowing out or species are flowing in right. Absolutely. It's a very it's a very systemic sort of approach you have to be taking. Yeah and especially on in there can be a wide range of ecosystems that really exist in such a very small land area so especially on the Hawaiian islands you can go from dry forests right on the coast and then up to the mountains it becomes much wetter where I work there's four meters of rain a year but down at Waikiki there's about half a meter so all those ecosystems are very connected and sometimes can occur just in that tiny little area so it's good to think about how they interface. Right and these days there's I mean there's a ton of pressures on these ecosystems right I mean not only there's pressures from urban growth and all but there are as you point out grazers agricultural pressures on them there are people cutting them down and plus then it's sort of the big overarching one right of changing climates right. Yeah yeah so where I work a lot of that basically the pressures were agriculture and the reason that we're able to restore on a large scale there is because a lot of the production of agriculture products which was mostly beef has actually moved over to China so that is a success story in the fact that we're able to now restore that land but there are a lot of places even think about prairies in the Midwestern United States that have this tiny little area now because of agricultural pressures but we don't really have the ability just because of human land use to restore those systems but it's good to just think about wherever we possibly can to try to reforest or bring back ecosystems that did persist in the past if that land is available if humans aren't actually using it. Right there's a there's an increasing recognition I think of what are sometimes called ecosystem services right and a recognition that these wild places on earth are actually providing things that we actually value besides just sort of peaceful serene pretty environment right where they're actually giving us potentially all kinds of valuable products. Yeah and there can be in a lot of times we can just think about decreasing runoff and thinking about water filtration but even in natural forests you can think about actually harvesting of products, forest products such as like harvesting of wood and there's a lot of ways that we can actually sustainably use ecosystems rather than just completely replacing them with for agricultural or other uses even though that is absolutely necessary to sustain our really incredibly skyrocketing global population but there are some ways such as agroforestry where we can actually think about transitioning systems that we're purely agricultural over to hybrids where we do have forest products and ag as well. Right right and particularly on small islands this this sort of mix of uses becomes really critical because it's just not not that much land right? Yeah whereas in Costa Rica where you're working it was essentially a continental jail right? Right you have a lot more space even though it's a very still kind of like post-it stamps size country it's you have a lot more space to actually do this kind of work. Right right so um so you're working there so what really brought you here and what are you going to be trying to do here in Hawaii? Yeah so um I started working about a year ago with the new director of lion arboretums Aksahawi and he works primarily in Costa Rica so I continued on my work there and then work with him in wet forests now but I'm actually starting up some new projects collaborating with the Hawaiian Replant Program at Lion Arboretum where I'm going to be looking at the outcomes of rare and endangered or threatened and endangered Hawaiian plant reintroductions so kind of leveraging my expertise and understanding of swell science and how plants respond to stress to try to really get at successes and failures and reintroductions and try to help get an idea of basically all of the outcomes that have occurred and then also try to help to make some recommendations to improve those reintroductions. Excellent because I understand you know there's a lot of a lot of variables in this the mountains here in Oahu which are have a lot of invasive species in them now and it's estimated if we could restore those who something like the original or quasi-original ecosystem we would get a tremendous amount less runoff from that forest tremendous amount more water or soaking in and we'd be essentially replenishing our aquifers at a much higher rate than right? Yeah especially because a lot of the invasive tree species here such as strawberry guava are really short-statured and you don't actually have that structure that you would as in you from a really a native Hawaiian wet forest so there's a lot to think about in terms of scoring on a really large scale. The plant reintroduction world is actually usually a much smaller scale and a lot of it is just trying to preserve the genetic material and all the really incredible native species that we have here in Hawaii. So I'm working more on a really kind of almost individual plant scale or even population scale but then the goal would be to use those general principles to then scale up which is always the goal to do landscape scale restoration and that kind of mess in with a lot of these really large scale global initiatives that have been developed recently to restore millions of hectares of forests and other ecosystems. Right but so a lot of it is a lion you'll take and set up a small plot somewhere and start trying to encourage the growth of some particular species that is extremely rare and getting more of them around so you can then start taking them out and planting them elsewhere and get multiple populations going right? Yeah and they're also just to look at all of the incredible work that's been done on the whole archipelago because people have been introducing reintroducing endangered species for many years now and they've had some really great successes and some challenges too so really just synthesizing all the information which people have been working on to try to actually think about general principles for doing those reintroductions is really great. That's great it hadn't occurred to me that yeah if people have been doing this it would be great to synthesize that knowledge because they're they're should be able to learn from the mistakes of others right and those successes right. Yeah excellent excellent that's and this certainly Hawaii well we may be one of the hot spots for invasive species that's at war but you said in Costa Rica but there are other places around the world right where the same kind of thing and not just the tropics up in the temperate zones too right? Yeah I actually started my work in science actually on understanding how an understory invasive species was impacting forest growth so there's a species called garlic mustard that is really just a pretty small ground covered species that actually become and really modify nutrient cycling so invasive species are a problem globally and it they can really impact lots of different lots of different systems aquatic systems are massively impacted by invasive species too. Sure I grew up in Florida and there were the water hyacinths which were introduced for whatever reason and gradually took over many bodies who are there and then the famous one in Florida of course is a kudzu right that was brought in in the 1930s as cattle feed and has turned into sort of a green blanket over much of the state. I mean in case like that is there are there people trying to deal though those that level of devastation to a natural ecosystem and if so what are they doing sort of sort of you know taking everything out and denoting it all? Yeah so I kind of work peripherally on invasive species but I can comment just generally so I I think there's a lot of removal programs and that has worked really well in certain cases but a lot of systems in I know of recent work in Hawaii where people are actually thinking about how to plant native species that actually persist well with those invasive so sometimes it's actually we need to recognize that we have novel ecosystems or systems that we can't just kind of notch back to exactly what they used to be before and just recognize that we can actually design systems that will bring back some of this native diversity but we may not be able to just totally take out all of the invasive stuff. Yeah well that's great and very timely so speaking of turning back the clock we are going to have to take a quick break here. Leland Worden, Lion Arboretum is with me here today. I'm your host Ethan Allen on Likeable Science. We'll take a one minute break and then we'll see you then. Aloha I'm Cynthia Sinclair and I'm Tim Appachella. We are hosts here at Think Tech Hawaii a digital media company serving the people of Hawaii. We provide a video platform for citizen journalists to raise public awareness in Hawaii. We are a Hawaii non-profit that depends on the generosity of its supporters to keep on going. We'd be grateful if you go to ThinkTechHawaii.com and make a donation to support us now. Thanks so much. Aloha this is Winston Welch. I am your host of Out and About where every other week Mondays at 3 we explore a variety of topics in our city state, nation and world and events, organizations, the people that fuel them. It's a really interesting show we welcome you to tune in and we welcome your suggestions for shows. You got a lot of them out there and we have an awesome studio here where we can get your ideas out as well. So I look forward to you tuning in every other week where we've got some great guests and great topics. You're going to learn a lot, you're going to come away inspired like I do. So I'll see you every other week here at 3 o'clock on Monday afternoon. Aloha. Welcome back to Likeable Science here on ThinkTech Hawaii. I'm your host Ethan Allen with me today in the ThinkTech Studio is Dr. Leland Worden from the Lion Arboretum and Leland and I were talking in the first half of the show about some of the work he's done, some issues in forest tropical dry forest restoration and all and we actually mentioned earlier that a lot of people don't particularly understand what sort of tropical dry forest is and what it looks like and I remember that you you had sent me some good photos. So we can go to the next slide here. So basically this is one of my field sites. This is a very degraded soil type called a vertisol and this is the forest that we actually sat to restore and this is about 20 years of regrowth here so you can see that there's really not much there. Right it doesn't look like a forest. Yeah so basically our idea was to try to first of all decide what species can really grow here because we don't really have a good reference ecosystem and another challenge you can go to the next slide here is that these soils flood a lot in the wet season so we have this really shrink and swall cycle of this really high clay content soil where they crack when it's dry and then flood when it's wet so this is another thing we really were trying to understand is how to pick species for this like challenging environment. Yeah yeah because as you say you can't turn the clock back so you've got to deal with the ongoing changes yeah and that must you don't know if species A really is going to go with species B right. Exactly yeah yeah so we've set out and actually started with 40 species which of about 160 species in this ecosystem tree species total is a lot. Actually we can go to the next slide here and basically planted them all out in a nursery and then tried to pick the best species out of 32 that could persist. So what do you say best what do you mean best? So specifically we're looking at survivorship survival and growth so whether or not because this is a pretty short time period that we're working with I'm over a PhD you have a limited time so I'm still monitoring this experiment but over two years what had the highest growth and what actually survived. Okay because all those were sort of native species so it was just sort of something sounds absolutely just you know hey let's let's go with whatever is going good right yeah and we tried a little bit with actually adding things to the soil to increase drainage and that in the end helped for initial survival but didn't really do anything in the long term so we found that it's really the species identity that's the most important thing. Yeah great so that's going on and and you figured this will the work you started these trees now are growing up and have turned from those little six inch one foot things into they're getting they're getting bigger yeah we have so we took that kind of the ideas from that initial experiment and then planted out six fill hectares which is about 17 acres each one of them approximately football field by a football field so to try to then answer some more management style questions on what we can we do with existing vegetation so we do have trees that are about three meters tall at this point so I'm actually going back in a month do a full survey of all the about 4500 that we planted in that experiment so I'll see I have to give an update on how tall they are at that point yeah excellent excellent yeah it is something a lot of people don't get to appreciate is to watch a tree really grow over years and years and years right yeah yeah and yeah it's it is exciting so uh and you're going to sort of take this same approach on a modified in a modified way into your work here but do we have another slide or two of your Costa Rica work do I see yeah so if we go to the next slide and the next two actually I just wanted to highlight the fact that all this work is done in collaboration with restoration practitioners so we really try to use do all of our work working with people that do this stuff on the ground so science doesn't exist in a total vacuum we really need to think about how to apply our questions on a large scale so these are images of all the people that helped me plant out but also just helped me plant all of or design all the experiments so we worked totally completely together working to think about initial questions through the final outcomes and developing our best practices right those images don't look like what people think about as doing science right yeah but people had had you collaboratively you would stand there with them and figure out what do they need here what's likely to grow here what would you like to see grow but we know probably isn't going to grow well here exactly and made all those calculations and you start digging in the dirt right lots of digging holes and then I mean watching plants grow but the digging holes takes a lot of time yeah and and it's uh it's a necessary part that's the way science proceeds right is just uh one experimenter time one little one little day in that case sort of one one seedling planted at a time exactly and excellent excellent so looking a little bit forward what do you see as some of the big challenges in ecosystem restoration are you hopeful for the field I mean do you think it seems to me there's a lot of ecosystems being degraded very rapidly and at this point in time and we're in a bit of a sort of a race as it were yeah so as much of as the challenges still really do exist there have been these really incredible global scale restoration projects started with the bond challenge developed by United Nations to basically get countries to pledge to restore millions of hectares of forest by 2030 and at this point many of these countries have already actually restored lots of forests so it's happening it's really and actually I'll highlight Brazil is a real success story where they've actually developed kind of changed their economy over a bit to have restoration be very important in terms of getting carbon credits but then also they have the infrastructure for people just being able to buy seedlings so they have really large-scale production nurseries that allow this to be pushed forward so we have to actually think about within our current both political and economic climate how to make these things happen and when countries really commit to doing this work it it happens so we need to actually think about talking to the people that really think about policy the most because to do things on a large scale you really have to work at that level right it has to really then take into account the sort of cultural norms social norms economic issues development because they can't country can't turn over a bunch of land if they're gonna something they have a bunch of people moving into that land right yeah so the people are honestly the most important so I care a lot about plants and I think about plants all the time and would love to just go and walk in a forest all day but in the end you really need to think about how doing restoration impacts people and how it benefits people and really pitching it in that way is kind of the way that my work is headed yeah yeah I mean more and more it seems this sort of idea that people have of the sort of pristine ecosystems untouched by human beings is sort of a myth like this one I mean virtually I don't want to say virtually every but huge amounts of the terrestrial landscape have been impacted in some way or another by human activity right yeah and there are relatively few spots that you could truly call pristine and untouched now yeah and humans have been impacting ecosystems for hundreds of thousands of years so it's it's better to really think about that component as being just part of how the world works how we can work with the ecosystems make them a little part of our economic well-being right so that you don't just burn them down they're gone you could say it's our best economic interest to have a sustained forest going here that's going to allow us to sell the agricultural products from it or bring the tourists in to see it or capture co2 to mitigate climate change exactly yeah exactly so it's a very uh it's a truly multidisciplinary approach that you're having to take right yeah as you point out earlier you're collaborating with the actual practitioners on the ground but at the same time you have to be talking to as you said policy makers the you know the economists probably literally uh and you know the developers the urban planners all these people right have have a finger in the pot yeah and that's honestly the hardest part is actually connecting my science with policy and i've i think about this a lot and i'm trying to do more of that kind of work and a lot of people are but it's really difficult to actually just saw a really great talk by dr robin chaston where she was really saying it's hard to get a seat at the table so it's really hard to integrate real um on the ground science with what policy is getting implemented but there's a lot of venues that and nonprofits that are working on on making that happen now yeah it's it's necessary on i think far beyond actually the realm of ecosystem restoration to have have policies governmental policies based on science and scientific evidence uh it's sort of foolish and foolhardy not to do so uh one can get in big trouble by ignoring the science and the science typically while it's not in any sense a silver bullet or a panacea it's a incredibly vital part of the information right you know and your ecosystem rest restoration is probably one of the clearest examples of that you can't do that work without a good scientific knowledge of what could possibly work what is working right yeah and like you said just the knowledge of what is happening in terms of human use of all those systems and i've um have talked with farmers about trying to actually plant trees on their land and there's a whole other host of concerns in terms of taking away economic viability and turning that to restoration so they're we really need to think about um doing things like agroforestry where we can plant some agroholder products with trees and do kind of hybrid hybrid ecosystem work at this point to make sure that everyone gets what they need yeah right yeah and that's of course actually you're in a wonderful area of the world for seeing agroforestry because a lot of the small islands in particular are have to do that by they're pushed into it so the marshals where they're just these tiny little sandbars basically yeah they're growing everything you know together with the trees and the yeah the root crops and everything all uh jowl as it were yeah there's really amazing work that's that has continued on on the Hawaiian islands working with agroforestry stuff yeah it's truly wonderful stuff and it's great to see enthusiastic articulate intelligent people like yourself doing this kind of work and much needed um so I guess do you have a 10 seconds of advice for students coming up uh yeah I guess I find what you love I mean the most important thing honestly is just knowing what you don't like to do and then at that point um it's finding something that you're passionate about is really the most important and there's benefits and drawbacks to everything but I have found a part where most of the time and most of my day I'm very happy about what I'm doing and I get to be outside and it's a challenge constantly but tinkering and answering questions about natural systems is super fun cool well we thank you for coming on and sharing all your knowledge here and thank you for what you're doing doing to the planet here uh Leland Weirton uh Lion Lion Arboretum has been with us today here on likeable science I'm your host Ethan Allen we hope you'll come back next week and uh here again until then