Author: Ana Gelevska

Wetlands are ecosystems with a wide array of soil types, vegetation, and water qualities, primarily determined by geographic location and climatic conditions. Some of the most common types of wetlands are floodplains, mangroves, salt marshes, peatlands, forests, and freshwater marshes. The wetlands are distributed widely across the landscape and are a fundamental constituent of US aquatic resources. Namely, wetlands are significant because these ecosystems filter pollutants from air and soil, store carbon, provide wildlife habitat, and prevent flooding. Additionally, wetlands are used locally as recreation areas. 

Stress Factors

Human Activities

Human activities significantly threaten the existence of wetlands and maintain these services. Humans take various steps that make life easier and better, such as agriculture and urban development, but at the same time, these actions endanger the wetlands. Also, several natural processes are stressors for the wetlands, such as erosion and flooding, jeopardizing wetlands in the US and the entire planet.

Wetlands usually occur as small isolated patches in mountain meadows and can be found as strips along rivers and streams and as large groups along the southern and eastern coasts of the US. The primary function of wetlands is absorbing runoff and filtering surface water, and in this process, wetlands collect excess sediment, nutrients, and other pollutants. These natural sponges support ecological processes, including hydrology, soil, and vegetation development. The surrounding area around the wetland should be minimally disturbed to provide the best results. Consequently, the “buffer” area will directly impact the overall ecological condition.   

Human activities substantially affect climate change and, at the same time, intensify the stressors. As a result of long-term shifts in temperatures and weather patterns, the frequency of occurrence of extreme precipitation and droughts has increased, and the sea levels are progressively rising. For example, an inland wetland, the Prairie Pothole Region in the north-central part of the US, provides a breeding environment for more than 50% of North American waterfowl species. In the past, this area has experienced temporary droughts, and if the trend of dry periods continues, scientists predict a dramatic drop in waterfowl breeding grounds.

Rising Sea Level

Increased sea levels immensely stress the coastal wetlands due to the saltwater invasion (increased salinity), reduced barriers to storm surges, and increased erosion. When the physical conditions in the wetlands change, plants and animals respond to those changes. Some local species could become extinct, and others expand their range, thus distressing the balance. By monitoring the plant changes, scientists can notice early warning signs of environmental changes and respond appropriately. When joined with the predicted erosion rates due to sea-level rise, current levels of wetlands will exponentially decrease. They will no longer serve as natural barriers to flooding during natural disasters.

Wetland Loss

Despite all efforts, statistical data shows that annually the United States loses about 60,000 acres of wetlands. If you find it difficult to imagine the size of that area – that’s almost equal to 35,000 football fields!

What can you do to protect the wetlands? You can start locally with these five simple and essential steps.

What Is Habitat Conservation?

The most common definition for habitat conservation is a management practice that creates plans for preserving, protecting, and restoring habitats and is responsible for preventing species extinction, fragmentation, or reduction in range.

History of Habitat Conservation

For centuries, nature was viewed as a resource for economic gain and controlled by government rules and regulations. The 18th and 19th centuries marked the beginning of the conservationist ideology. The ideology included three core principles: 

• Identifying human activities that impact the environment
• Ensuring environmental preservation for future generations
• Conducting conservation efforts responsibly

The first regulatory application of conservation principles was established in the forests of British India. Sir James Ranald Martin was a pre-eminent British military surgeon in India. He encouraged the notion that there are links between human and environmental health. He published medico-topographical reports demonstrating damage from large-scale deforestation and desiccation. Martin used his research to lobby for forest conservation activities in British India.

In 1842 the Madras Board of Revenue, led by botanist Alexander Gibson, started local conservation efforts in British India. This forest conservation program was adopted based on scientific principles, making it the first case of state conservation management of forests. In 1855, Governor-General Lord Dalhousie introduced the first permanent and large-scale forest conservation program in the United States and other colonies. This program promoted the inception of the world’s first national park in 1872: Yellowstone National Park.

By the mid-20th century, people began to appreciate the value of nature itself rather than focusing on the economic benefits. Various movements and activist groups raised awareness to protect natural capital. Several countries, including the United States, Canada, and Britain, enacted legislation to protect the most fragile environments and ecosystems.

The Importance of Habitat Conservation

Today, governments and non-governmental organizations worldwide are creating policies focused on protecting habitats and preserving biodiversity. The commitment and daily actions of volunteer associations in local communities make an enormous difference in ensuring that future generations understand the importance of natural resource conservation.

Habitats serve a multitude of organisms, and therefore it is of utmost importance to preserve them. Several reports have documented habitat loss in fragile ecosystems, such as coastal and inland wetlands, coastal sage scrub, oak woodlands, vernal pools, and free-flowing rivers. Moreover, many endangered species are found in these habitats. Degraded or reduced habitat area leads to species extinction. The fundamental relationship between habitat and species requires habitat protection to conserve biological diversity.

Strategic Habitat Conservation (SHC)

U.S. Fish and Wildlife Service (USFWS) created the SHC approach to establish self-sustaining wildlife populations with landscape and system sustainability. This adaptive management framework informs decisions to expand resources for wildlife species or species groups in priority landscapes with biological importance. The SHC identifies and selects areas or regions and decides where and how to deliver conservation effectively and achieve predicted outcomes, which are crucial in sustaining endangered species, fish, and wildlife populations.

The strategic conservation of habitats is an ongoing process that includes biological planning with measurable outcomes. The objectives of the SHC design include different management practices and ecological functions for various species. Additionally, monitoring, research, and evaluation are the basis of every decision, grounded in the best science available.      

Partnerships with the U.S. Geological Survey, State and Tribal wildlife agencies, conservation organizations, landowners, and other individuals and organizations with extensive knowledge of the issues allow SHC to assess the risk better and provide effective solutions for landscapes that need conservation.

Strategic Conservation Framework

Through strategic habitat conservation, the USFWS takes strategic, accountable, and adaptive action toward conserving ecosystems. The consistent use of this framework enables the workforce to create a solid plan and creative design and deliver strategically planned conservation actions. Moreover, shared outcomes help members to operate in a more coordinated and collaborative way. The science-driven conservation framework enables project transparency and an extensive, detailed decision-making process.

Strategic habitat conservation focuses on large-scale projects in wildlife and natural resource conservation. Some of the program goals with the SHC include land conversion efforts; improving environmental conditions that impact wildlife; providing reports for the increased public demand for transparency and interagency collaboration; sustaining species, populations, communities, and systems instead of the management of separate resources components; implementation of science-intensive approaches.

Sources

Arcata Fish and Wildlife Office. (n.d.). Strategic Habitat Conservation. U.S. Fish and Wildlife Service. Retrieved from: https://www.fws.gov/office/arcata-fish-and-wildlife/strategic-habitat-conservation

Whether one prefers long walks, hikes, or connecting with wildlife through meditation and exercise, spending time in nature is beneficial for mental and physical health and wellbeing. Over time, as population increases and towns and cities occupy larger areas, nature is more difficult to access. As people migrate to urban areas, they tend to forget the importance of spending time outside in nature. According to an article by Hannah Ritchie and Max Roser, it is predicted that by 2050, close to 7 billion people will live in urban areas (Ritchie & Roser, 2018).

Wetlands and Urbanization

Wetlands are water-rich natural areas that occur mainly along rivers, coastal plains, and deltas. These areas are often subject to urbanization. As a result of urban expansions, groundwater levels decrease, which puts pressure on wetland functions.

Urban wetlands serve as green spaces where city dwellers can recreate and connect with nature. These wetlands are designed so that the polluted water from its surroundings is filtered through the artificial wetland. Unlike natural wetlands, flow patterns can change and specific zones fall dry over time. Artificial wetlands are partially controlled by humans, making these wetlands less dynamic than natural wetlands. As a result, certain visual qualities and uses remain seemingly unchanged over time.

Artificial Wetlands as Affordable Wastewater Treatment

Urban wetlands have the capability to purify urban water efficiently and affordably. Unlike conventional waste-water treatment systems, artificial wetlands are a substantially cheaper solution that require minimal maintenance (EPA, 2015).

The EPA provides several resources for the design and implementation constructed wetlands for the purpose of recycling urban wastewater. They state in their article “Constructed Wetlands for Wastewater Treatment and Wildlife Habitat” that constructed wetlands treatment systems fall into two categories: Free Water Surface Systems and Subsurface Flow Systems. These categories are differentiated by their targeted use objectives; Subsurface Flow Systems are focused on improving water quality, while Free Water Surface Systems are utilized to improve wetland habitat functions (EPA, 2015). Subsurface Flow Systems are designed to filter water through a permeable material below the wetlands surface, as to not create any nuisances or odors (EPA, 2015). This system would be an ideal mechanism for urban wetlands as residents could enjoy the green space while the wastewater below them is purified.

Both natural and urban wetlands play a critical role in coastal stabilization and flood protection. Sediment settles down in deltas, thus creating a natural barrier that prevents water from penetrating deeper into the soil. The multiple roles wetlands play for humans, as well as urban environments, are the reason why more constructed wetlands have been utilized as green space in recent years.

Importance of Urban Wetlands for Overall Wellbeing 

The benefits of urban wetlands’ ecosystem services are immeasurable, but how are urban wetlands used as a means of social prescribing? Does spending time in nature, specifically wetlands, positively impact overall health and wellbeing? 

Several studies related to physiological and psychological changes show positive changes when people move from urban areas to rural environments. Evidence suggests that coastal habitats have been shown to improve our health, body, and mind (Garrett et al., 2019). However, it is unknown whether wetlands have the same psychological affects.

For that purpose, the Wildfowl and Wetlands Trust and Imperial College London undertook an innovative study with the primary goal to collect scientific evidence to demonstrate the importance of urban wetlands and social prescribing. The results suggest that urban wetlands improve the mood and increase the positive energy in all participants (Reeves et al., 2021). Even stressed participants showed a higher influence of wetland benefits (Reeves et al., 2021). The conclusion was that urban wetlands provide an opportunity to stop and reduce stress or bring individuals to ‘baseline’ (Reeves et al., 2021). By having a network of urban wetlands, people can quickly recharge and manage feelings such as stress, depression, and anxiety, as well as the added benefits for biodiversity and pollution control.     

Sources:

Environmental Protection Agency. (2015). Constructed wetlands for wastewater treatment and wildlife habitat. Environmental Protection Agency. Retrieved from https://www.epa.gov/sites/default/files/2015-10/documents/2004_10_25_wetlands_introduction.pdf.

Garrett, J.K., Clitherow, T.J., White, M.P., Wheeler, B.W., Fleming, L.E. (2019). Coastal proximity and mental health among urban adults in England: The moderating effect of household income. Health & Place, 59: 102200. Retrieved from https://doi.org/10.1016/j.healthplace.2019.102200.

Reeves, J.P., John, C.H.D., Wood, K.A., & Maund, P.R. (2021). A qualitative analysis of UK wetland visitor centres as a health resource. International Journal of Environmental Research and Public Health, 18(16): 8629. Retrieved from doi: 10.3390/ijerph18168629.

Ritchie, H. & Roser, M. (2018). Urbanization. Our World in Data. Retrieved from https://ourworldindata.org/urbanization#citation.

Nuclear Testing Engenders Environmentalism

As mentioned in the previous article, the massive amounts of fallout released during the 1950’s are still present around the globe. Historian, Laura Bruno, describes in her article that the nuclear tests’ radioactive isotopes created and released as the “first environmental pollutant to take on the dimensions of a global threat.” She continues in her article that “as a result of fallout, scientists learned that pollutants could travel over long periods and distances, and that they could be accumulated in a reservoir in organic matter. This research revealed how interconnected different ecosystems are and led to the view that our global environment cannot tolerate endless pollutants” (Bruno, 2003).

Prior to World War II’s Manhattan Project and America’s effort to build an atomic bomb, there was limited knowledge on how radioactive particles were used in nuclear testing, how they spread, the persistence, the accumulation of radioisotopes, and how they would affect the environment.

The first systematic studies were likely made in 1943 at the Hanford plutonium plant. The Applied Fisheries Laboratory used x-rays to observe radioactive effects on salmon and trout in the Columbia River. Once the Hanford reactor began operating, samples were taken from the river which showed increased levels of radioactive material surrounding the plutonium plant (Anter, 2019). The laboratory traced several radioactive isotopes in water, which allowed them to develop a method to measure nuclear fallout.

The development of tools for analyzing fallout allowed different isotopes to be measured during the Cold War. These particles affected air, water, soil, plants, animals, and humans. Project Gabriel, commissioned by the Atomic Energy Commission (AEC) in 1949, sought to determine how many atomic bombs could be detonated without radioactive contamination to cause severe health effects from environmental contamination. Plutonium, strontium-90 (Sr-90), and yttrium-90 were the most dangerous isotopes released by fission weapons. Project Gabriel found that strontium-90 was the most hazardous resulting from nuclear detonations, due to the high amounts released into the atmosphere. Moreover, due to its similarity to calcium, living organisms could absorb it. In humans, this isotope accumulates in the bones and remains present in the body for several decades.

Following the discoveries made in Project Gabriel, Project Sunshine sought to determine the concentration and behavior of strontium-90 in the environment. The project’s report devoted substantial attention to methods of gathering their data from human remains, and concluded that there was a more pronounced accumulation of Sr-90 in adults, as infant bones have a faster growth rate. Project Sunshine, among other projects, was intended to remain classified from the public. However, when the project was leaked in 1953, the AEC received public backlash from the method in which they conducted this study. Upon the discovery of these research projects, the public started to become suspicious of the government’s assurances on the harmlessness of fallout. Citizens living near atomic test sites in the Nevada desert believed they experienced health disorders due to the fallout. 

As suspicions over the effects of fallout rose, a thermonuclear accident at the Bikini atoll in 1954 had worldwide significance. After the detonation of the Bravo device, the fallout cloud did not follow the predicted route due to the high winds. This allowed the fallout cloud to extend over a vast area outside the security zone. More than 250 individuals, including Marshallese, American military personnel, and Japanese fishermen, developed radiation sickness from the cloud. Some the severe cases of radiation sickness attracted public attention. The Japanese Ministry of Health and Welfare program discovered that 5% of fish caught after the cloud dispersed were too radioactive for consumption.

The Bikini incident and several other Pacific surveys raised public awareness of the harmful effects of fallout. It was discovered that even countries without an atomic program were affected by fallout. The fact that isotopes spread globally and are quickly introduced into the human food chain could no longer be kept a secret by AEC. This increased awareness and became the ground for the environmental movement (Bruno, 2003).

Weapons Testing and Climate Science

Climate science and nuclear weapon testing have a long-term and intertwined relationship. As a consequence of the Fukushima disaster, the Comprehensive Test Ban Treaty Organization tracked the radioactive plume emanating from damaged Japanese nuclear reactors. The global network of monitoring stations, a sophisticated model descendant of computer models created for testing fallout from weapon testing, successfully measured airborne radionuclides.

Over time, the methods of tracking radiation through the atmosphere have a practical application that extends far beyond the nuclear industry. For example, this method has been crucial for measuring anthropogenic climate change and tracing its major contributors. This includes measuring radioactive carbon and the way it cycles through the atmosphere, the oceans, and the biosphere. Some of the earliest global climate models relied on numerical methods similar to those developed by nuclear weapon designers. Even today, environmental scientists use mathematical models based on nuclear testing. Namely, these models have been created to predict and analyze the shock waves produced by nuclear explosions.

During the Cold War, the countries fighting for nuclear domination built facilities to create and test weapons. The labs in these facilities were equipped with powerful supercomputers with expertise in modeling and managing collected data sets to investigate the nuclear fallout. Today, they are used to observe climate change models. Researcher, Paul Edwards, states in his article that “the laboratories built to create the most fearsome arsenal in history are doing what they can to prevent another catastrophe – this one caused not by behemoth governments at war, but by billions of ordinary people living ordinary lives within an energy economy that we must now reinvent” (Edwards, 2012).

The impact of nuclear testing on the climate is another significant historical intersection between climate science and nuclear activities. Nuclear weapon designers have opened many possibilities to research and better understand the atmosphere. The knowledge about atmospheric carbon dioxide and its role in the greenhouse effect has helped both environmental scientists and political leaders understand the full extent of nuclear activities and the environmental damage caused by it.

Moratorium on Nuclear Testing

From 1945 until 1998, there were over 2000 nuclear tests conducted worldwide. Today, after thousands of detonations and irreparable damage in terms of human casualties and environmental damage, none of the world’s nuclear-armed states are conducting nuclear tests for the first time since the beginning of the nuclear age. In 1990, the Soviet Union proposed a moratorium on nuclear testing, and the United Kingdom and the United States agreed to a comprehensive ban on all nuclear testing. The last nuclear tests were conducted throughout the early 1990’s, after which, on 24 September 1996, 182 countries signed the Comprehensive Nuclear-Test-Ban Treaty (CNTBT).

Nuclear Activities Today

Despite the ratification of the CNTBT in several countries, several nuclear tests were conducted in North Korea, India, and Pakistan between 1998-2017. These countries broke the de facto moratorium that the CTBT had established with this action. India conducted two underground tests, with the government emphasizing that the explosions were for military testing. Pakistan reacted to India’s move by conducting two underground nuclear tests, after which both countries immediately announced unilateral moratoriums on nuclear testing and have conducted no nuclear tests since 1998. North Korea is the only country that has conducted nuclear tests in the 21st century. All tests were discovered by the Comprehensive Nuclear-Test-Ban Treaty verification regime. The regime is designed to detect any nuclear explosion on Earth – underground, underwater, or in the atmosphere. After determining North Korea’s compliance with the CTBT, the UN Security Council unanimously adopted sanction resolutions.

Sources:

Anter, S. (2019). 5 facts about Hanford. Colombia Riverkeeper. Retrieved from https://www.columbiariverkeeper.org/news/2019/8/5-facts-about-hanford

Bruno, L.A. (2003). The bequest of the nuclear battlefield: Science, nature, and the atom during the first decade of the Cold War. Historical Studies in the Physical and Biological Sciences, 33(2), 237-260. Retrieved from https://doi.org/10.1525/hsps.2003.33.2.237

Edwards, P.N. (2012). Entangled histories: Climate science and nuclear weapons research. Bulletin of the Atomic Scientists, 68(4), 28-40. Retrieved from DOI: 10.1177/0096340212451574

What is a dead zone? 

Dead zones are low-oxygen areas of the world’s oceans or large lakes. These hypoxic areas have too little oxygen to supports marine life. Although the hypoxic zones are a natural phenomenon, many of the dead zones today are created or enhanced by human activities, and are increasing in shallow coastal and estuarine areas.

Dead zones created by nutrient pollution in bays, lakes, and coastal waters are the most common and problematic since they receive excess nutrients from upstream sources. Excess nitrogen and phosphorus lead to algae overgrowth in a short period of time. This overgrowth of algae consumes large amounts of oxygen and blocks sunlight from reaching underwater plants. Eventually, the algae will die, sink to the bottom of the water body, and the oxygen in the water is used for bacterial decomposition. Creating an oxygen sink and inhabitable conditions for aquatic life.

More harmful algae blooms can be wide-spanning and produce chemicals or toxins. Toxic blooms commonly occur in lakes, reservoirs, rivers, ponds, bays, and coastal waters. In most cases, cyanobacteria, also known as blue-green algae, is the cause of harmful algae blooms. The toxins produced by cyanobacteria can harm both human health and aquatic life.

How can dead zones form? 

Eutrophication is the main driver of dead zone formation. As a result of human activities, nitrogen levels are almost doubled, and phosphorus levels are tripled compared to the natural values of these substances that flow into the environment. This has been attributed to the increased use of nitrogen and phosphorous fertilizers, nitrogen fixation by leguminous crops, and atmospheric deposition of oxidized nitrogen from the combustion of fossil fuels (Dybas, 2005). Additionally, some of the nutrient sources found in coastal waters are lawn fertilizers, agricultural manure, sewage output, and stormwater. The amount of nutrients found in nature was limited, however, as human activities have increased, nutrient pollution has lead to massive algal blooms and, ultimately, dead zones. Harmful algal blooms can lead to fish kills, contaminated drinking water, shellfish poisoning, and the death of marine mammals and shore birds.

Another factor contributing to the formation of dead zones is water column stratification due to the difference in water density. For instance, in the Gulf of Mexico, eutrophication initiates a massive phytoplankton growth on the water’s surface. The size of this plankton population surpasses the natural capacity of consumers to graze it down to a balanced level. After their relatively short lifespan, the plankton die and sink to the bottom waters, where bacteria decomposition occurs. During the summer months, the water column is stratified from the limited mixing from wind and wave energy. Additional environmental factors (i.e. temperature and salinity) create stratified layers of water from top to bottom. Freshwater flowing from rivers and the warmed surface water have low density which forms a layer above the cool, dense seawater near the bottom. This stratification leaves the bottom layer isolated from the regular resupply of oxygen from the atmosphere. Organisms capable of swimming have the ability to escape the dead zone, but sessile fauna experience stress or die (NOAA, n.d.).

Categorizing Eutrophic Systems: Where are dead zones? 

Scientists have identified 415 dead zones worldwide. Over the years, there has been a staggering increase in the number of dead zones at a global level. In 1960 there were about 10 documented cases, and in less than 50 years, the number dramatically increased to 169 in 2007. A majority of the dead zones are located along the eastern coast of the United States and the coastlines of the Baltic States, Japan, and the Korean Peninsula.

Considering the dramatic increase in dead zones, scientists have prioritzed coastal systems experiencing any symptoms of eutrophication. Namely, a coastal system that exhibits the effects of eutrophication is considered an area of concern. These areas are at the most significant risk of developing hypoxia. There are 233 areas of concern along the western coast of Central and South America and the coastlines of Great Britain and Australia.

Despite the increasing amount of dead zones in our waters, there are systems in recovery from hypoxia. For example, the Black Sea is a system that once experienced yearly hypoxic events, but is now in a state of recovery and improvement. Similarly, Boston Harbor in the United States and the Mersey Estuary in the United Kingdom have improved water quality.

The Largest Dead Zone in the World

The number of dead zones and their size and exact location varies each year. The overall area of dead zones across the world is estimated to be at least 1,544,263 square miles, an area equal to the size of the European Union (Loyd-Smith & Immig, 2018). The largest dead zones are the Gulf of Oman – 63,700 square miles, the Baltic Sea – 27,027 square miles, and the Gulf of Mexico – 6,952 square miles (Carstensen & Conley, 2019; NOAA, 2019; Queste et al., 2018).

The Impact of Dead Zones

In addition to the environmental impact, dead zones have a negative effect on the economy. For fishermen who rely on the ocean to provide a livelihood, dead zones mean they have to travel greater distances from shores to find areas where fish congregate. This is impossible for small boats, and there is added cost for fuel and staff members. According to NOAA estimations, dead zones cost the U.S. seafood and tourism industries approximately $82 million annually.

What are the solutions?

Reducing nutrient pollution and keeping fertilizers on land and out of coastal water is the primary goal of lowering dead zones. And the best way to accomplish that is through cooperation at the international level. The ecosystems in the world’s oceans are fragile. Increasing hypoxia and dead zones, warming oceans, and rising acidification create multiple stressors to marine ecosystems.  

Sources:

Carstensen, J. & Conley, D. J. (2019). Baltic Sea hypoxia takes many shapes and sizes. Bulletin of Limnology and Oceanography, 28(4), 125-129. Retrieved from doi:10.1002/lob.10350.

Dybas, C.L. (2005). Dead zones spreading in world oceans. BioScience, 55(7), 552–557. Retrieved from https://doi.org/10.1641/0006-3568(2005)055[0552:DZSIWO]2.0.CO;2

Lloyd-Smith, M. & Immig, J. (2018). Ocean pollutants guide: Toxic threats to human health and marine life. IPEN. Retrieved from https://ipen.org/sites/default/files/documents/ipen-ocean-pollutants-v2_1-en-web.pdf

NOAA. (2019). Large ‘Dead Zone’ measured in Gulf of Mexico. National Oceanic and Atmospheric Administration. Retrieved from https://www.noaa.gov/media-release/large-dead-zone-measured-in-gulf-of-mexico

NOAA. (2011). Congressional interest in harmful algae and dead zone bill prompts hearing. National Centers for Coastal Ocean Science. Retrieved from https://coastalscience.noaa.gov/news/cscor-provides-testimony-to-congress-in-support-of-harmful-algae-and-hypoxia-law/

NOAA. (n.d.). Operational Gulf of Mexico hypoxia monitoring. National Centers for Coastal Ocean Science. Retrieved from https://coastalscience.noaa.gov/project/operational-gulf-of-mexico-hypoxia-monitoring/

Queste, B. Y., et al. (2018). Physical controls on ocean distribution and denitrification potential in the north west Arabian Sea. Geophysical Research Letters, 45(9), 4143-4152. Retrieved from doi:10.1029/2017GL076666.