By Dr Bill McGraw

One complaint I regularly hear about aquaculture is that it can negatively impact the environment by the direct destruction of valuable estuarine habit, like mangroves, to make an area for pond construction. In addition to this, aquaculture ponds can discharge nutrient-rich effluents in coastal environments which often causes oxygen depletion, resulting in killing local fauna, as well as causing intense algal blooms and settleable solids which can blanket the bottom of estuaries causing mortalities of sedentary organisms like oysters and clams. 

Another problem with corporate aquaculture is that viruses, antibiotic resistant bacteria and parasites are released into the environment during effluent discharge, which can infect local marine life. A classic example of this, which can be readily found on the internet, is sea lice which attach to the skin of salmon grown in aquaculture pens, which basically suck the life out of them. The sea lice then reproduce and infect wild fish that travel through adjacent waterways near the aquaculture cages.

Utilizing closed recirculation systems that are biosecure and don’t exchange water, all of the problems described above can be eliminated. I have spent 25 years working in the field of aquaculture creating algal based systems that don’t release any water and instead recycle and collect all waste so that it can be applied to plants grown in soil. I have determined over the course of 10 years of research that aquaculture waste contains all the essential elements that a plant needs, and includes incredible amounts of phosphorous and nitrogen, eliminating the need for synthetic fertilizers made from fossil fuels and mined from the earth. So these benefits are just awesome for the environment. 

An added advantage of applying aquaculture waste to plants is that once nutrient deficiencies are eliminated, plants are less vulnerable to pests, cancelling the need for pesticide application. Moreover, the vigorous growth of plants quickly cover available area, reducing light, slowing the growth of weeds. Currently in Panama, the outrageous, long term use of glyphosate has resulted in the proliferation of super weeds that are not only resistant to herbicides, but also grow at a much faster rate and aggressively outcompete valuable plants for nutrients and space. I have experienced this for over a decade while working here in Panama. The weeds here are an absolute nuisance. 

Another environmental benefit of recirculating, zero water exchange systems is that they are small and can be located just about anywhere. I have developed an inexpensive greenhouse structure (3$/m²) that can withstand the 2.5 meters of rain we get here in Panama as well as the intense north and south winds that regularly destroy more common greenhouse structure designs. By locating aquaculture recirculating systems further inland away from sensitive habitat, estuary systems can remain intact and pristine. 

And lastly, another complaint purported by internet health enthusiasts is that a tilapia grown in aquaculture tanks or ponds is bad for you and you should not eat it. This of course is just not true. Fish grown on corn and soybeans are high in omega-6s and low in omega-3s which can create inflammatory conditions in the human body when consumed. It is important to note here that inflammation is the main culprit in the current worldwide viral pandemic which is negatively affecting nearly everyone on the planet. However, fish and shrimp grown in algal rich, zero water exchange systems are naturally high in omega-3s as algae is a healthy and natural superfood. After all, you are what you eat. 

We need to take the time to find food that is good for us or grow our own. My company, Panama Fresh Organic, that is thriving here in Panama, regularly delivers super fresh seafood directly to people within hours of harvest. This is unheard of in Panama as there are no seafood stores, and seafood bought from pick-up trucks that regularly travel around is often of poor quality, sometimes not even on ice. Unfortunately, the availability of fresh and tasty shrimp is non-existent, as all shrimp that are grown here are frozen with preservative added and shipped to Europe, while wild-caught offered for sale requires very close inspection to ensure adequate freshness for safe consumption. Aquaculture can have a positive impact on the environment and provide some great nutrition at the same time. As climate conditions worsen with floods destroying croplands, trade wars causing disruption in the accessibility of seafood and supply chains slowing certain types of food availability, smaller, more local, biosecure, totally contained and fully integrated systems will become more valuable. It is important that we understand the importance of these systems and give them our full support.

Plant and animal species across the world are steadily disappearing due to human activity. A major new IIASA-led study suggests that without ambitious, integrated action combining conservation and restoration efforts with a transformation of the food system, turning the tide of biodiversity by 2050 or earlier will not be possible.

Biodiversity – the variety and abundance of species, along with the extent and quality of the ecosystems they call home – has been declining at an alarming rate for many years. It is clear that we cannot allow the current trend to continue. If it does, there will simply not be enough nature left to support future generations. While ambitious targets have been proposed, practical issues such as feeding the Earth’s growing human population could make reaching such targets a challenge.

The study, which has been published in Nature and forms part of the latest World Wide Fund for Nature (WWF) Living Planet Report, for the first time set out to explore biodiversity targets as ambitious as a reversal in global biodiversity trends and shed light on what integrated future pathways to achieving this goal might entail.

“We wanted to assess in a robust manner whether it might be feasible to bend the curve of declining terrestrial biodiversity due to current and future land use, while avoiding jeopardizing our chances to achieve other Sustainable Development Goals (SDGs),” explains study lead author and IIASA researcher David Leclère. “If this were indeed possible, we also wanted to explore how to get there and more specifically, what type of actions would be required, and how combining various types of actions might reduce trade-offs among objectives and instead exploit synergies.” 

Using multiple models and newly developed scenarios to explore how addressing these elements in an integrated way might help reach biodiversity targets, the study provides key information on pathways that could materialize the 2050 vision of the UN Convention on Biological Diversity – “Living in harmony with nature”. For global trends of terrestrial biodiversity as affected by land use change to stop declining and start recovering by 2050 or earlier, the researchers say that action is needed in two key areas:

• Bold conservation and restoration efforts together with increased management effectiveness, will have to rapidly be stepped up. The study assumes that protected areas quickly reach 40% of global terrestrial areas. This should happen in tandem with large efforts to restore degraded land (reaching about 8% of terrestrial areas by 2050 in the study scenarios) and land use planning efforts that balance production and conservation objectives on all managed land. Without such efforts, declines in biodiversity may only be slowed down rather than halted and any potential recovery would remain slow.
• Food system transformation: As bold conservation and restoration efforts alone will likely be insufficient, additional measures are needed to address global pressures on the food system. Efforts to bend the curve of global terrestrial biodiversity include reduced food waste, diets that have a lower environmental impact, and further sustainable intensification and trade.

Integrated action would however need to be taken in both areas simultaneously to bend the biodiversity loss curve upward by 2050 or earlier.

“In a scenario with increased conservation and restoration efforts alone, almost half of biodiversity losses estimated in the counterfactual business-as-usual scenario could not be avoided, a bending was not observed for all models, and when it did occur, it was often only in the second half of the 21st century. In addition, we found that bold conservation and restoration efforts alone might increase the price of food products, thereby potentially hampering future progress on eliminating hunger,” says Michael Obersteiner, an IIASA researcher and Director of the Environmental Change Institute at Oxford University. 

Conversely, scenarios that combined increased conservation and restoration efforts with efforts to transform the food system showed that opportunities for ambitious conservation and restoration efforts were larger, and potential adverse food security impacts defused, thereby securing a bending of global trends in global terrestrial biodiversity as affected by land use change by 2050. Finally, such transformative change in food and land use systems would also deliver significant co-benefits such as a large contribution to ambitious climate mitigation targets, reduced pressure on water resources, reduced excess of reactive nitrogen in the environment, and health benefits.

According to the authors, a true reversal of biodiversity declines will however likely necessitate an even broader set of actions, addressing biodiversity loss jointly with climate change. 

“If unmitigated, emerging threats to biodiversity such as climate change and biological invasions may become as important as land-use change – the largest biodiversity threat to date – in the future. A true bending of biodiversity losses will necessitate ambitious climate change mitigation that exploits synergies with biodiversity, rather than further eroding biodiversity,” says Andy Purvis, professor at the Imperial College London, and researcher at the National History Museum in the UK. 

With the Strategic Plan for Biodiversity 2011-2020 coming to an end with mixed outcomes, the study’s findings are directly relevant to on-going negotiations at the United Nations Convention on Biological Diversity. 

“This study shows the world may still be able to stabilize and reverse the loss of nature. But to have any chance of doing that as early as 2030 we will need to make transformational changes in the way we produce and consume food as well as bolder, more ambitious conservation efforts,” says Mike Barrett, executive director of science and conservation at WWF-UK and a coauthor of the study. “If we don’t do this, and continue with business as usual, we will end up with a planet that cannot support current and future generations of people. Never has a “New Deal for Nature and People” that halts and starts to reverse biodiversity loss, been needed more.” 

Reference

Leclere D, Obersteiner M, Barrett M, Butchart SHM, Chaudhary A, De Palma A, DeClerck FAJ, Di Marco M, et al. (2020). Bending the curve of terrestrial biodiversity needs an integrated strategy. Nature DOI: 10.1038/s41586-020-2705-y

About IIASA:

The International Institute for Applied Systems Analysis (IIASA) is an international scientific institute that conducts research into the critical issues of global environmental, economic, technological, and social change that we face in the twenty-first century. Our findings provide valuable options to policymakers to shape the future of our changing world. IIASA is independent and funded by prestigious research funding agencies in Africa, the Americas, Asia, and Europe. www.iiasa.ac.at

Environmental hazards affect populations worldwide and can drive migration under specific conditions, especially in middle-income and agricultural countries. According to a new study, changes in temperature levels, increased rainfall variability, and rapid-onset disasters such as tropical storms play an important role in this regard.

Environmental migration is most pronounced in middle-income and agricultural countries and weaker in low-income countries where populations often lack the resources needed to move away. The findings of the study by the Potsdam Institute for Climate Impact Research (PIK), IIASA, the Vienna Institute of Demography of the Austrian Academy of Sciences, and the Vienna University of Economics and Business, make it possible to identify geographical regions that may be especially susceptible to migration movements in the future.

“Environmental factors can drive migration, but the size of the effects depends on the particular economic and sociopolitical conditions in the countries,” explains lead author Roman Hoffmann from PIK and the Vienna Institute of Demography of the Austrian Academy of Sciences. “In both low and high income countries, environmental impacts on migration are weaker – presumably because either people are too poor to leave and therefore essentially become trapped, or in wealthy countries, they have enough financial means to absorb the consequences. It is mainly in middle-income regions and those with a dependency on agriculture that we see strong effects.” 

The meta-analysis study, which analyzed 30 previously published studies on the topic, reveals a number of interesting patterns. It shows, for example, that impacts on migration vary by types of environmental  hazards and that different hazards can reinforce each other. 

“While changing temperatures in a region are found to have the strongest impact on migration, rapid-onset disasters, and rainfall variability and anomalies can also play a role. Especially smallholder farmers rely on steady climatic conditions and suffer from changes and shocks as they have insufficient capacities to adapt,” comments coauthor and Deputy IIASA World Population Program Director, Raya Muttarak, who is also affiliated with the Wittgenstein Centre for Demography and Global Human Capital (IIASA, VID/ÖAW, University of Vienna).

The researchers emphasize that there is no automatism at play – environmental migration always depends on a number of economic and sociopolitical factors. The narrative of climate refugees pushing towards Europe or the US may be too simplistic. For instance, the researchers found compelling evidence that environmental changes in vulnerable countries predominantly lead to internal migration or migration to other low- and middle-income countries rather than cross-border migration to high-income countries. Affected populations often migrate to places within their own region and eventually return to their homes within a relatively short period of time.

The findings, which have been published in the latest issue of Nature Climate Change, also hint at regions that are highly vulnerable to climate change where environmental migration may be particularly prevalent. 

“Our research suggests that populations in Latin America and the Caribbean, several countries in sub-Saharan Africa – especially in the Sahel region and East Africa – as well as Western, Southern and Southeast Asia are particularly at risk,” says coauthor Anna Dimitrova from the Vienna Institute of Demography of the Austrian Academy of Sciences.

Given the expected rise of global average temperatures, the researchers believe that the topic of environmental migration will become more important in the future. Consequently, interventions have to be tailored to the actual situations on the ground that support affected populations and reduce vulnerabilities. 

“The best way to protect those affected is to stabilize the global climate by rapidly reducing greenhouse gas emissions from burning fossil fuels as well as simultaneously enhance adaptive capacity such as through improving human capital,” says Jesus Crespo Cuaresma, a researcher with the IIASA World Population Program and professor of Economics at the Vienna University of Economics and Business. “While migration can be an effective adaptation strategy for households, it can be involuntary and could come with non-negligible consequences both for the migrants, their household members, and people at the place of destination.”

Reference

Hoffmann R, Dimitrova A, Muttarak R, Crespo Cuaresma J, & Peisker J (2020). A Meta-Analysis of Country-Level Studies on Environmental Change and Migration. Nature Climate Change DOI: 10.1038/s41558-020-0898-6

About IIASA:

The International Institute for Applied Systems Analysis (IIASA) is an international scientific institute that conducts research into the critical issues of global environmental, economic, technological, and social change that we face in the twenty-first century. Our findings provide valuable options to policymakers to shape the future of our changing world. IIASA is independent and funded by prestigious research funding agencies in Africa, the Americas, Asia, and Europe. www.iiasa.ac.at