Crafting mines from satellite images

By Victor Maus, alumnus of the IIASA Ecosystems Services and Management Program and researcher at the Vienna University of Economics and Business

The mining of coal, metals, and other minerals causes loss of natural habitats across the entire globe. However, available data is insufficient to measure the extent of these impacts. IIASA alumnus Victor Maus and his colleagues mapped more than 57,000 km² of mining areas over the whole world using satellite images.

 

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Our modern lifestyles and consumption patterns cause environmental and social impacts geographically displaced in production sites thousands of kilometres away from where the raw materials are extracted. Complex supply chains connecting mineral mining regions to consumers often obscure these impacts. Our team at the Vienna University of Economics and Business is investigating these connections and associated impacts on a global-scale www.fineprint.global.

However, some mining impacts are not well documented across the globe, for example, where and how much area is used to extract metals, coal, and other essential minerals are unknown. This information is necessary to assess the environmental implications, such as forest and biodiversity loss associated with mining activities. To cover this data gap, we analyzed the satellite images of more than 6,000 known mining regions all around the world.

Visually identifying such a large number of mines in these images is not an easy task. Imagine you are flying and watching from the window of a plane, how many objects on the Earth’s surface can you identify and how fast? Using satellite images, we searched and mapped mines over the whole globe. It was a very time-consuming and exhausting task, but we also learned a lot about what is happening on the ground. Besides, it was very interesting to virtually visit a vast range of mining places across the globe and realize the large variety of ecosystems that are affected by our increasing demand for nature’s resources.

The result of our adventure is a global data set covering more than 21,000 mapped areas adding up to around 57,000 km² (that is about the size of Croatia or Togo). These mapped areas cover open cuts, tailings dams, piles of rocks, buildings, and other infrastructures related to the mining activities — some of them extending to almost 10 km (see figure below). We also learned that around 50 % of the mapped mining area is concentrated in only five countries, China, Australia, the United States, Russia, and Chile.

Examples of mines viewed from Google Satellite images. (a) Caraj\'{a}s iron ore mine in Brazil, (b) Batu Hijau copper-gold mine in Indonesia, and (c) Super Pit gold mine in Australia. In purple is the data collected for these mines (Figure source: www.nature.com/articles/s41597-020-00624-w).

Using these data, we can improve the calculation of environmental indicators of global mineral extraction and thus support the development of less harmful ways to extract natural resources. Further, linking these impacts to supply chains can help to answer questions related to our consumption of goods. For example, which impacts the extraction of minerals used in our smartphones cases and where on the planet they occur? We hope that many others will use the mining areas data for their own research and applications. Therefore, the data is fully open to everyone. You can explore the global mining areas using our visualization tool at www.fineprint.global/viewer or you can download the full data set from doi.pangaea.de/10.1594/PANGAEA.910894. The complete description of the data and methods is in our paper available from www.nature.com/articles/s41597-020-00624-w.

This blog post first appeared on the Springer Nature “Behind the paper” website. Read the original post 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.

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.

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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.

Modeling ancient history to inform the future

By Marcus Thomson, IIASA alumnus and a researcher at the National Center for Ecological Analysis and Synthesis (NCEAS), the University of California, Santa Barbara

IIASA alumnus Marcus Thomson explains how what we have learnt about prehistoric farming cultures can be used to provide useful insights on human societal responses to climate change.

The climate of the western half of the North American continent, between the Rocky Mountains and the Pacific coastal region, is dry by European standards. The American Southwest, in particular, centered roughly on the intersection of the states of Colorado, New Mexico, Arizona, and Utah, is predominantly desert between high mountain plateaus. It is, and has always been, a challenging environment for farmers. Yet the prehistoric Southwest was home to complex maize-based agricultural societies. In fact, until the 19th century growth of industrial cities like New York, the Southwest contained ruins of the largest buildings north of Mexico — and these had been abandoned centuries before the Spanish arrived in the Americas.

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For more than a century, researchers have pored over data, from proxies of paleo-environmental change, to historiographies collected by explorers, to archaeology and computational models of human occupation, and produced a detailed picture of the socio-environmental, economic, and climatic conditions that could explain why these sites were abandoned. While details vary in fine-grained analyses of the various sub-groupings of peoples in the region, the big picture is one of societal transformation in adapting to climate change.

Also important is just how the climate changed during the period, because similar dynamics are expected to emerge in the future as a consequence of global warming. European historians point to a medieval era with generally warmer mean annual temperatures. In the Southwestern United States however, which is more sensitive to changes in drought than temperature, the period between roughly AD 850 to 1350 is known as the Medieval Climate Anomaly (MCA). The warm, dry MCA was followed by a long stretch of increased changes in the availability of water, known as the Little Ice Age (LIA). More frequent “warm droughts” at the end of the MCA, and generally increasing changes in water resources at the onset of the LIA, is thought to be a good analogy for future conditions in western North America.

When I had the good fortune to visit IIASA as a participant of the Young Scientists Summer Program (YSSP) in 2016, I worked with research scholars Juraj Balkovič and Tamás Krisztin to develop a model of ancient Fremont Native American maize. The Fremont were an ancient forager-farmer people who lived in the vicinity of modern Utah. We used a climate model reconstruction of the temperature and rainfall between AD 850 and 1450 to drive this maize crop model, and compared modeled crop yields against changes in radiocarbon-derived occupations – in other words, the information gathered from carbon dated artifacts that show that an area was occupied by a particular people – from a few archaeological areas in Utah.

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Among our findings was that changes in local temperatures appeared to play a larger role in the lives, practices and habits of the people who lived there than changes in regional, long-term temperature conditions [1]. Later, while a researcher at IIASA myself, I returned to the subject with one of our coauthors, professor Glen MacDonald of the University of California, Los Angeles, using an expanded geographic range and a more sophisticated treatment of radiocarbon dated occupation likelihoods.

We used the climate model to reconstruct prehistoric maize growing season lengths and mean annual rainfall for Fremont sites. We found that the most populous and resilient Fremont communities were at sites with low-variability season lengths; and low populations coincided with, or followed, periods of variable season lengths. This study confirmed the important dependence on climate variability; and more importantly, our results are in line with others on modern smallholder farming contexts.

More details on our latest study [2] have just been published online in Environmental Research Letters (ERL). It will become part of an ERL special issue looking at societal resilience drawing lessons from the past 5000 years. Studies like these can give useful insights on human societal responses to climate change because these ancient civilizations are, in a sense, completed experiments with complex human-environmental systems. For decision makers, who must plan early to commit resources to offset the effects of future climate change on smallholder farmers in similarly drought-sensitive, marginally productive environments, these studies indicate that year-to-year climatic variability drives occupation change more than long-term temperature change.

References:

[1] Thomson MJ, Balkovič J, Krisztin T, & MacDonald GM (2019). Simulated impact of paleoclimate change on Fremont Native American maize farming in Utah, 850–1449 CE, using crop and climate models. Quaternary International, 507, pp.95-107 [pure.iiasa.ac.at/15472]

[2] Thomson MJ, & MacDonald GM (In press). Climate and growing season variability impacted the intensity and distribution of Fremont maize farmers during and after the Medieval Climate Anomaly based on a statistically downscaled climate model. Environmental Research Letters.

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.

Cost effective solutions to manage nutrient pollution in the Yangtze

By Maryna Strokal, Department of Environmental Sciences, Water Systems and Global Change, Wageningen University and Research, The Netherlands

Maryna Strokal discusses a new integrated approach to finding cost-effective solutions for nutrient pollution and coastal eutrophication developed with IIASA colleagues.

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Have you ever wondered why the water in some rivers appear to be green? The green tinge you see is due to eutrophication, which means that too many nutrients – specifically nitrogen and phosphorus – are present in the water. This happens because rivers receive these nutrients from various land-based activities like run-off from agricultural fields and sewage effluents from cities. Rivers in turn export many of these nutrients to coastal waters, where it serves as food for algae. Too many nutrients, however, cause the algae and their blooms to grow more than normal. Because algae consumes a lot of oxygen, this lowers the available oxygen supply in the water, killing off fish and other marine life. Some algae can also be toxic to people when they eat seafood that have been exposed to, or fed on it. Polluted river water on the other hand, is unfit for direct use as drinking water, or for cooking, showering, or any of our other daily needs. Before we can use this water, it needs to be treated, which of course costs money.

To better understand and address these issues, I worked with colleagues from IIASA, Wageningen University, and China to develop an integrated approach to identify cost-effective solutions (read cheapest) to reduce river pollution and thus coastal eutrophication. Our integrated approach takes into account human activities on land, land use, the economy, the climate, and hydrology. We implemented the new approach for the Yangtze Basin in China.

The Yangtze is the third longest river in the world and exports nutrients from ten sub-basins to the East China Sea, where the coast often experiences severe eutrophication problems that may increase in the coming years. The Chinese government has called for effective actions to ensure clean water for both people and nature.

In our paper on this work, which was recently published in the journal Resources, Conservation, and Recycling, my colleagues and I conclude that reducing more than 80% of nutrient pollution in the Yangtze will cost US$ 1–3 billion in 2050. This cost might seem high, but it is actually far below 10% of the income level in the Yangtze basin. We also identified an opportunity in the negative or zero cost range, which would result in a below 80% reduction in nutrient export by the Yangtze. This negative or zero cost alternative involves options to recycle manure on land and reduce the use of chemical fertilizers (Figure 1). More recycling means that farmers will buy less chemical fertilizers and potential savings can then compensate for the expenses related to recycling the manure. We also illustrated the costs that would be involved for ten sub-basins to reduce their nutrient export to coastal waters.

Figure 1. Summarized illustration of eutrophication causes and cost-effective solutions for reducing nutrient export by Yangtze and thus coastal eutrophication in the East China Sea in 2050.

Recycling manure on cropland is an important and cost-effective solution for agriculture in the sub-basins of the Yangtze River (Figure 1). Manure is rich in the nutrients that crops need, and opting for this alternative instead of chemical fertilizers avoids loss of nutrients to rivers, and thus ultimately to coastal waters. Current practices are however still far from ideal, with manure – and especially liquid manure – often being discharged into water because crop and livestock farms are far away from each other, which makes it practically and economically difficult to transport manure to where it is needed. Another reason is the historical practice of farmers using chemical fertilizers on their crops – it is simply how they are used to doing things. Unfortunately, the amounts of fertilizers that farmers apply are often far above what crops actually need, thus leading to river pollution.

The Chinese government are investing in combining crop and livestock production, in other words, they are creating an agricultural sector where crops are used to feed animals and manure from the animals is in turn used to fertilize crops. Chinese scientists are working with farmers to implement these solutions.

In our paper, we showed that these solutions are not only sustainable, but also cost-effective in terms of avoiding coastal eutrophication. We invite you to read our paper for more details.

References

Strokal M, Kahil T, Wada Y, Albiac J, Bai Z, Ermolieva T, Langan S, Ma L, et al. (2020). Cost-effective management of coastal eutrophication: A case study for the Yangtze River basin. Resources, Conservation and Recycling 154: e104635. https://doi.org/10.1016/j.resconrec.2019.104635.

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.

Advocating for a new ecology grounded in systems science

By Brian Fath, Young Scientists Summer Program (YSSP) scientific coordinator, researcher in the Advanced Systems Analysis Program, and professor in the Department of Biological Sciences at Towson University (Maryland, USA) and Soeren Nors Nielsen, Associate professor in the Section for Sustainable Biotechnology, Aalborg University, Denmark

IIASA Young Scientists Summer Program (YSSP) scientific coordinator, Brian Fath and colleagues take an extended look at the application of the ecosystem principles to environmental management in their book, A New Ecology, of which the second edition was just released.

IIASA is known for some of the earliest studies of ecosystem dynamics and resilience, such as work done at the institute under the leadership of Buzz Holling. The authors of the book, A New Ecology, of which the second edition was just released, are all systems ecologists, and we chose to use IIASA as the location for one of the brainstorming meetings to advance the ideas outlined in the book. At this meeting, we crystallized the idea that ecosystem ontology and phenomenology can be summarized in nine key principles. We continue to work with researchers at the institute to look for novel applications of the approach to socioeconomic systems – such as under the current EU project, RECREATE – in which the Advanced Systems Analysis Program is participating. The project uses ecological principles to study urban metabolism – a multi-disciplinary and integrated platform that examines material and energy flows in cities as complex systems.

Our book argues the need for a new ecology grounded in the first principles of good science and is also applicable for environmental management. Advances such as the United Nations Rio Declaration on Sustainable Development in 1992 and the more recent adoption of the Sustainable Development Goals (2015) have put on notice the need to understand and protect the health and integrity of the Earth’s ecosystems to ensure our future existence. Drawing on decades of work from systems ecology that includes inspiration from a variety of adjacent research areas such as thermodynamics, self-organization, complexity, networks, and dynamics, we present nine core principles for ecosystem function and development.

The book takes an extended look at the application of the ecosystem principles to environmental management. This begins with a review of sustainability concepts and the confusion and inconsistencies of this is presented with the new insight that systems ecology can bring to the discussion. Some holistic indicators, which may be used in analyzing the sustainability states of environmental systems, are presented. We also recognize that ecosystems and society are physically open systems that are in a thermodynamic sense exchanging energy and matter to maintain levels of organization that would otherwise be unattainable, such as promoting growth, adaptation, patterns, structures, and renewal.

Another fundamental part of the evolution of the just mentioned systems are that they are capable of exhibiting variation. This property is maintained by the fact that the systems are also behaviorally open, in brief, capable of taking on an immense number of combinatorial possibilities. Such an openness would immediately lead to a totally indeterminate behavior of systems, which seemingly is not the case. This therefore draws our attention towards a better understanding of the constraints of the system.

One way of exploring the interconnectivity in ecosystems is taking place mainly through the lens of ecological network analysis. A primer for network environment analysis is provided to familiarize the reader with notation including worked examples. Inherent in energy flow networks, such as ecosystem food webs, the real transactional flows give rise to many hidden properties such as the rise in indirect pathways and indirect influence, an overall homogenization of flow, and a rise in mutualistic relations, while hierarchies represent conditions of both top-down and bottom-up tendencies. In ecosystems, there are many levels of hierarchies that emerge out of these cross-time and space scale interactions. Managing ecosystems requires knowledge at several of these multiple scales, from lower level population-community to upper level landscape/region.

Viewing the tenets of ecological succession through a lens of systems ecology lends our attention the agency that drives the directionality stemming from the interplay and interactions of the autocatalytic loops – that is, closed circular paths where each element in the loop depends on the previous one for its production – and their continuous development for increased efficiency and attraction of matter and energy into the loops. Ecosystems are found to show a healthy balance between efficiency and redundancy, which provides enough organization for effectiveness and enough buffer to deal with contingencies and inevitable perturbations.

Yet, the world around us is largely out of equilibrium – the atmosphere, the soils, the ocean carbonates, and clearly, the biosphere – selectively combine and confine certain elements at the expense of others. These stable/homoeostatic conditions are mediated by the actions of ecological systems. Ecosystems change over time displaying a particular and identifiable pattern and direction. Another “unpleasant” feature of the capability for change is to further evolve through collapses. Such collapse events open up creative spaces for colonization and the emergence of new species and new systems. This pattern includes growth and development stages followed by the collapse and subsequent reorganization and launching to a new cycle.

A good theory should be applicable to the concepts in the field it is trying to influence. While the mainstream ecologists are not regularly applying systems ecology concepts, the purpose of our book is to show the usefulness of the above ecosystem principles in explaining standard ecological concepts and tenets. Case studies from the general ecology literature are given relating to evolution, island bio-geography, biodiversity, keystone species, optimal foraging, and niche theory to name a few.

No theory is ever complete, so we invite readers to respond and comment on the ideas in the book and offer feedback to help improve the ideas, and in particular the application of these principles to environmental management. We see a dual goal to understand and steward ecological resources, both for their sake and our own, with the purpose of an ultimate sustainability.

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.