Can seaweed be the solution to our land problems?

By Neema Tavakolian, 2021 IIASA Science Communication Fellow

Young Scientists Summer Program (YSSP) participant Scott Spillias explores how the adoption of offshore seaweed farming could affect land use.

Seaweed farming in the clear coastal waters of Zanzibar island © Ecophoto | Dreamstime.com

Since the start of the industrial revolution, the Earth’s population has grown exponentially, and it is still growing every year. In addition to heavy population growth, human advances in medicine, science, and technology have allowed people to live longer lives as well. As more countries industrialize, the demand for land extensive commodities like meat and dairy have also increased. Deforestation has risen worldwide making way for cattle and other livestock grazing, and more of the food we grow is being dedicated towards livestock rather than human consumption.

With problems like unsustainable land use, climate change, and suburban sprawls in places like the United States and Australia decreasing available arable lands, this poses the question: is there any way we can feed a growing population without further damaging ecosystems and contributing to climate change? In addition to achieving this goal, we simultaneously want to promote equitable and just societies. 2021 YSSP participant Scott Spillias believes he might have a solution: seaweed.

Spillias has a background in marine biology and sailing. After years of sailing the world, he could see the alarming state of our oceans. Wanting to be part of the solution, he moved to Australia to study oceanic food systems, environmental economics, and environmental decision making at the University of Queensland.

Scott Spillias © Scott Spillias

“We live on an ocean planet, yet almost all of the food we grow comes from land. When it comes to the sea, we are essentially just unsustainably hunting and gathering from our oceans. I want to know what it would look like if instead, we tried to farm them,” Spillias explains.

Spillias says that seaweed as an agricultural product is already useful with its range of uses including food, livestock feed, fuel, fertilizer, and multiple products in the form of hydrocolloids. Hydrocolloids, more commonly known as “gums”, are extracted from plants like seaweeds and algae; they are used as setting and thickening agents in a variety of products including foods and pharmaceuticals, often increasing shelf life and quality.

A University of California, Davis study found that incorporating seaweed in cattle feed could reduce methane emissions from beef cattle by as much as 82%. Moreover, seaweed’s broad range of uses can hypothetically decrease land usage in favor of sea usage. Seaweeds also serve many ecological roles such as filtering ocean waters, serving as nurseries for small fish and crustaceans, and protecting sea floors.

There are two types of seaweed farming in use today. In parts of China, South Korea, and Japan there is floating offshore seaweed production, where the seaweed is grown and harvested while floating in deep waters. Another form of seaweed farming seen in Indonesia, Tanzania, and the Philippines involves a different approach, where the seaweed is grown and farmed closer to the coast in shallower waters, or the intertidal zone. Both provide ecosystem services, jobs, and food for local populations.

As part of his YSSP project this summer, Spillias hopes to use the IIASA Global Biosphere Management Model (GLOBIOM) to determine land-use changes brought about by large-scale seaweed production.

“We are going to assume that the seaweeds we are growing will be for food, feed, and fuel. We are also taking certain constraints into consideration, such as the inability to place seaweed farms in high traffic shipping areas or marine protected zones. Getting rough estimates of seaweed production can then give us an idea of land commodities we can replace, for instance, corn used for biofuel,” he says.

Spillias hopes that this research can provide results that can influence policy.

“Locally, seaweed farming will either be beneficial or destructive – it depends on where you put it and how you do it. Zooming out and understanding how these tradeoffs relate to terrestrial production will give policymakers a clearer idea of whether to promote or restrict the practice.”

Note: This article gives the views of the author, and not the position of the Nexus blog, nor of the International Institute for Applied Systems Analysis.

Making the Top 100 in Ecology: the story of a successful research paper

By Florian Hofhansl, researcher in the Biodiversity, Ecology, and Conservation Research Group of the IIASA Biodiversity and Natural Resources Program

Florian Hofhansl writes about a successful paper on which he was the lead author that was recently ranked #32 on the list of the Top 100 most downloaded ecology papers published in 2020.

Early in 2020, one of my manuscripts titled “Climatic and edaphic controls over tropical forest diversity and vegetation carbon storage” was accepted for publication in the prestigious journal Nature Scientific Reports.

Initially, I was worried about the bad timing when I was informed that the paper would be published on 19 March – right at the onset of the COVID-19 pandemic – since it took me and my colleagues almost a decade to collect the data and publish our results on the biodiversity and functioning of tropical forest ecosystems.

However, my worries completely disappeared when I learned that our research article had received more that 3,000 downloads, placing it among the top 100 downloaded ecology papers for Scientific Reports in 2020. This is an extraordinary achievement considering that Scientific Reports published more than 500 ecology papers in 2020. Seeing our paper positioned at #32 of the top 100 most downloaded articles in the field, therefore meant that our science was of real value to the research community.

We kicked off our study in the dry-season of 2011 by selecting twenty one-hectare forest inventory plots at the beautiful Osa peninsula – one of the last remnants of continuous primary forest – located in southwestern Costa Rica. We did not expect that our project would receive this much scientific recognition as we were merely interested in describing the stunning biodiversity of this remote tropical region. Nevertheless, we were striving to understand the functioning of the area’s megadiverse ecosystem by conducting repeated measurements of forest characteristics, such as forest growth, tree mortality, and plant species composition.

After periodically revisiting the permanent inventory plots, and recording data for almost a decade, we found stark differences in the composition of tropical plant species such as trees, palms, and lianas across the landscape. Most interestingly, these different functional groups follow different strategies in their competition for light and nutrients, both limiting plant growth in the understory of a tropical rainforest. For instance, lianas – which are long-stemmed, woody vines – are relatively fast growing and try to reach the canopy to get to the sunlight, but they do not store as much carbon as a tree stem to reach the same height in the canopy. In contrast, palms share a different strategy and mostly stay in the lower sections of the forest where they collect water and nutrients with their bundles of palm leaves arranged upward to catch droplets and nutrients falling from above, thus reducing local resource limitation.

Lead author Florian Hofhansl and field botanist, Eduardo Chacon-Madrigal got stuck between roots of the walking palm (Socratea exorrhiza), while surveying one of the twenty one-hectare permanent inventory plots © Florian Hofhansl

Our results indicate that each plant functional group – that is, a collection of organisms (i.e., trees, palms, or lianas) that share the same characteristics – was associated with specific climate conditions and distinct soil properties across the landscape. Hence, this finding indicates that we would have to account for the small-scale heterogeneity of the landscape in order to understand future ecosystem responses to projected climate change, and thus to accurately predict associated tropical ecosystem services under future scenarios.

Our study and its subsequent uptake by the research community, illustrates the value of conducting on-site experiments that empower researchers to understand crucial ecosystem processes and applying these results in next-generation models. Research like this makes it possible for scientists to evaluate vegetation–atmosphere feedbacks and thus determine how much of man-made emissions will remain in the atmosphere and therefore might further heat up the climate system in the future.

Our multidisciplinary research project furthermore highlighted that it is crucial to gather knowledge from multiple disciplines, such as botany (identifying species), plant ecology (identifying functional strategies), and geology (identifying differences in parent material and soil types) – since all of these factors need to be considered in concert to capture the complexity of any given system, when aiming to understand the systematic response to climate change.

Read more about the research here: https://tropicalbio.me/blog

Reference:

Hofhansl F, Chacón-Madrigal E, Fuchslueger L, Jenking D, Morera A, Plutzar C, Silla F, Andersen K, et al. (2020). Climatic and edaphic controls over tropical forest diversity and vegetation carbon storage. Scientific Reports DOI: 10.1038/s41598-020-61868-5 [pure.iiasa.ac.at/16360]

Note: This article gives the views of the author, and not the position of the Nexus blog, nor of the International Institute for Applied Systems Analysis.

From pasture to plate: can beef be produced sustainably?

By Shorouk Elkobros, 2020 IIASA Science Communication Fellow

Being mindful of biodiversity loss and environmental impact can disrupt the beef industry globally, here’s how.

In his new polemical Netflix documentary, A life on our planet, Sir David Attenborough argues that, “We live on a finely tuned life support machine, one that relies on its biodiversity to run smoothly.”

The decline in biodiversity challenges the world’s capacity to produce food for a growing population. That is ironic when global food production itself is a contributing factor to biodiversity loss, especially beef production.

What’s wrong with the beef industry?

Here are a couple of the current challenges facing the beef industry: Cows are major culprits in climate change because they emit methane, a potent greenhouse gas. Beef production is the number one driver of deforestation and habitat loss in tropical forests. Grazing cattle also require a large amount of grass that requires using harsh nitrogen fertilizers. Hence, the beef production industry contributes heavily to biodiversity loss, which has dire consequences for the planet.

©Jonathan Casey | Dreamstime.com

There is no silver bullet to solve the challenges beef production poses to the environment. Research is going above and beyond to find diverse and integrated solutions that can go hand in hand to combat this challenge. Whether through ways to reduce methane emissions, such as creating an anti-burp vaccine for cows, designing lab-grown meat, or shifting diets to plant-based alternatives.

Katie Lee, an alumna of the 2020 IIASA Young Scientists Summer Program (YSSP) and PhD student at the University of Queensland in Brisbane, Australia, is part of a broader project that focuses on redistributing where we produce beef to minimize its impact on greenhouse gas emissions and biodiversity, as well as on the cost of production.

“I am particularly interested in ways to enhance the types of beef production systems. With the challenges of its water use, greenhouse gas emissions, and the large areas of land it requires compared to any other food source, any small changes we propose can have a big impact,” she explains.

For Lee, solutions to global food security are crucial, and looking at the status of production systems is both a need and a must. The world population is expected to reach 9.7 billion people by 2050. So, when thinking about ways to feed 10 Billion people by 2050, it becomes clear that it is not enough to simply look at beef alternatives without enhancing its current demand and supply chains. Lee thinks it is more efficient to pragmatically alter and improve the environmental impact of beef production than to convince people to stop eating beef.

It is understood that reducing beef consumption has health benefits. However, with a growing interest in alternative meat options, the question remains of which markets this appeals to, and how environmentally friendly and energy- and water intensive these alternatives are.

“While demand reduction on meat is important, sometimes it is not feasible in countries that do not have economic security or are still growing in terms of affluence, which leads to an increase in beef consumption. That is why we need to look at the producer side and the consumer side, as well as everything in between to have the biggest impact. I was particularly interested to conduct this research in cooperation with IIASA, mainly because the institute has a good history of looking at the impact of beef, particularly in terms of greenhouse gas emissions,” says Lee.

A win-win all-round solution

Using the IIASA Global Biosphere Management Model (GLOBIOM), Lee is assessing the impact on greenhouse gas emissions and biodiversity when shifting both the production and demand of beef. Preliminary results from her ongoing study show a reduction in impact on biodiversity and greenhouse gas emissions, as well as a reduction of the producer price when switching away from extensive grazing systems  ̶  a win-win situation all-round.

“Few studies explicitly address biodiversity loss compared to investigating ways to reduce greenhouse gas emissions. I want to show stakeholders that beef production can be more efficient in terms of reducing its impact on greenhouse gas emissions and biodiversity. I am hopeful that this study can help beef producers to be mindful of this when making choices. That will be a win for the environment if it goes together with a proactive reduction of meat consumption,” concludes Lee.

Similar to Lee’s study and using a set of large-scale economic models including GLOBIOM, the IIASA AnimalChange research project aims to assess the global scale adaptation and mitigation options of the livestock sector to ensure a sustainable livestock production sector by 2050.

Limiting global warming and protecting biodiversity should be a priority when designing food systems able to feed an increasing population. As a food producer, whether you raise cattle or design cell cultured meat, it is important to be conscious about livestock hoof prints on biodiversity. As a food consumer, it is necessary to be mindful of having a healthy and sustainable diet that does not put the planet in jeopardy. Sustainable beef production might not be the panacea to future biodiversity loss or food scarcity, yet it can offer a significant change.

Note: This article gives the views of the author, and not the position of the Nexus blog, nor of the International Institute for Applied Systems Analysis.

How to reverse global wildlife declines by 2050

IIASA researchers Michael Obersteiner, David Leclère, and Piero Visconti discuss the findings of their latest paper, which proposes pathways to reverse the current trend of biodiversity loss and shows that the next 30 years will be pivotal for the Earth’s wildlife.

Species are going extinct at an unprecedented rate. Wildlife populations have fallen by more than two-thirds over the last 50 years, according to a new report from the World Wildlife Fund. The sharpest declines have occurred throughout the world’s rivers and lakes, where freshwater wildlife has plummeted by 84% since 1970 – about 4% per year.

But why should we care? Because the health of nature is intimately linked to the health of humans. The emergence of new infectious diseases like COVID-19 tend to be related to the destruction of forests and wilderness. Healthy ecosystems are the foundation of today’s global economies and societies, and the ones we aspire to build. As more and more species are drawn towards extinction, the very life support systems on which civilization depends are eroded.

Even for hard-nosed observers like the World Economic Forum, biodiversity loss is a disturbing threat with few parallels. Of the nine greatest threats to the world ranked by the organization, six relate to the ongoing destruction of nature.

© Chris Van Lennep | Dreamstime.com

Economic systems and lifestyles which take the world’s generous stocks of natural resources for granted will need to be abandoned, but resisting the catastrophic declines of wildlife that have occurred over the last few decades might seem hopeless. For the first time, we’ve completed a science-based assessment to figure out how to slow and even reverse these trends.

Our new paper in Nature featured the work of 60 coauthors and built on efforts steered by the Intergovernmental Panel on Biodiversity and Ecosystem Services. We considered ambitious targets for rescuing global biodiversity trends and produced pathways for the international community to follow that could allow us to meet these goals.

Bending the curve

The targets of the UN Convention on Biological Diversity call for global trends of terrestrial wildlife to stop declining and start recovering by 2050 or earlier. Changes in how land is used – from pristine forest to cropland or pasture – rank among the greatest threats to biodiversity on land worldwide. So what are the necessary conditions for biodiversity to recover during the 21st century while still supporting growing and affluent human societies?

Two key areas of action stand out from the rest. First, there must be renewed ambition from the world’s governments to establish large-scale conservation areas, placed in the most valuable hotspots for biodiversity worldwide, such as small islands with species found nowhere else. These reserves, in which wildlife will live and roam freely, will need to cover at least 40% of the world’s land surface to help bend the curve from decline to recovery for species and entire ecosystems.

The location of these areas, and how well they are managed, is often more important than how big they are. Habitat restoration and conservation efforts need to be targeted where they are needed most – for species and habitats on the verge of extinction.

The next 30 years will prove pivotal for Earth’s biodiversity. Leclère et al. (2020) © IIASA

Second, we must transform our food systems to produce more on less land. If every farmer on Earth used the best available farming practices, only half of the total area of cropland would be needed to feed the world. There are lots of other inefficiencies that could be ironed out too, by reducing the amount of waste produced during transport and food processing, for example. Society at large can help in this effort by shifting towards healthier and more sustainable diets, and reducing food waste.

This should happen alongside efforts to restore degraded land, such as farmland that’s becoming unproductive as a result of soil erosion, and land that’s no longer needed as agriculture becomes more efficient and diets shift. This could return 8% of the world’s land to nature by 2050. It will be necessary to plan how the remaining land is used, to balance food production and other uses with the conservation of wild spaces.

Without a similar level of ambition for reducing greenhouse gas emissions, climate change will ensure the world’s wildlife fares badly this century. Only a comprehensive set of policy measures that transform our relationship with the land and rapidly scale down pollution can build the necessary momentum. Our report concludes that transformative changes in our food systems and how we plan and use land will have the biggest benefits for biodiversity.

But the benefits wouldn’t end there. While giving back to nature, these measures would simultaneously slow climate change, reduce pressure on water, limit nitrogen pollution in the world’s waterways and boost human health. When the world works together to halt and eventually reverse biodiversity loss, it’s not only wildlife that will thrive.

This article originally appeared on The Conversation. Read the original article here.

Note: This article gives the views of the authors, and not the position of the Nexus blog, nor of the International Institute for Applied Systems Analysis.

Mapping habitats in support of biodiversity research

By Martin Jung, postdoctoral research scholar in the IIASA Ecosystems Services and Management Program.

IIASA postdoc Martin Jung discusses how a newly developed map can help provide a detailed view of important species habitats, contribute to ongoing ecosystem threat assessments, and assist in biodiversity modeling efforts.

Biodiversity is not evenly distributed across our planet. To determine which areas potentially harbor the greatest number of species, we need to understand how habitats valuable to species are distributed globally. In our new study, published in Nature Scientific Data, we mapped the distribution of habitats globally. The habitats we used are based on the International Union for Conservation of Nature (IUCN) Red List habitat classification scheme, one of the most widely used systems to assign species to habitats and assess their extinction risk. The latest map (2015) is openly available for download here. We also built an online viewer using the Google Earth Engine platform where the map can be visually explored and interacted with by simply clicking on the map to find out which class of habitat has been mapped in a particular location.

Figure 1: View on the habitat map with focus on Europe and Africa. For a global view and description of the current classes mapped, please read Jung et al. 2020 or have a look at the online interactive interface.

The habitat map was created as an intersection of various, best-available layers on land cover, climate, and land use (Figure 1). Specifically, we created a decision tree that determines for each area on the globe the likely presence of one of currently 47 mapped habitats. For example, by combining data on tropical climate zones, mountain regions and forest cover, we were able to estimate the distribution of subtropical/tropical moist mountainous rain forests, one of the most biodiverse ecosystems. The habitat map also considers best available land use data to map human modified or artificial habitats such as rural gardens or urban sites. Notably, and as a first, our map also integrates upcoming new data on the global distribution of plantation forests.

What makes this map so useful for biodiversity assessments? It can provide a detailed view on the remaining coverage of important species habitats, contribute to ongoing ecosystem threat assessments, and assist in global and national biodiversity modeling efforts. Since the thematic legend of the map – in other words the colors, symbols, and styles used in the map – follows the same system as that used by the IUCN for assessing species extinction risk, we can easily refine known distributions of species (Figure 2). Up to now, such refinements were based on crosswalks between land cover products (Figure 2b), but with the additional data integrated into the habitat map, such refinements can be much more precise (Figure 2c). We have for instance conducted such range refinements as part of the Nature Map project, which ultimately helped to identify global priority areas of importance for biodiversity and ecosystem services.

Figure 2: The range of the endangered Siamang (Symphalangus syndactylus) in Indonesia and Malaysia according to the IUCN Red List. Up to now refinements of its range were conducted based on land cover crosswalks (b), while the habitat map allows a more complete refinement (c).

Similar as with other global maps, this new map is certainly not without errors. Even though a validation has proved good accuracy at high resolution for many classes, we stress that – given the global extent and uncertainty – there are likely fine-scale errors that propagate from some of the input data. Some, such as the global distribution of pastures, are currently clearly insufficient, with existing global products being either outdated or not highly resolved enough to be useful. Luckily, with the decision tree being implemented on Google Earth Engine, a new version of the map can be created within just two hours.

In the future, we plan to further update the habitat map and ruleset as improved or newer data becomes available. For instance, the underlying land cover data from the European Copernicus Program is currently only available for 2015, however, new annual versions up to 2018 are already being produced. Incorporating these new data would allow us to create time series of the distribution of habitats. There are also already plans to map currently missing classes such as the IUCN marine habitats – think for example of the distribution of coral reefs or deep-sea volcanoes – as well as improving the mapped wetland classes.

Lastly, if you, dear reader, want to update the ruleset or create your own habitat type map, then this is also possible. All input data, the ruleset and code to fully reproduce the map in Google Earth Engine is publicly available. Currently the map is at version 003, but we have no doubt that the ruleset and map can continue to be improved in the future and form a truly living map.

Reference:

Jung M, Raj Dahal P, Butchart SHM, Donald PF, De Lamo X, Lesiv M, Kapos V,Rondinini C, & Visconti P (2020). A global map of terrestrial habitat types. Nature Scientific Data DOI: 10.1038/s41597-020-00599-8 

Note: This article gives the views of the author, and not the position of the Nexus blog, nor of the International Institute for Applied Systems Analysis.