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Aquatic Ecosystem

Introduction of aquatic ecosystem.

An ecosystem is defined as a functional unit wherein all living organisms interact with their surroundings and one another to sustain themselves in the environment. In a broad sense, an ecosystem can be categorized as a land/terrestrial ecosystem or a water/aquatic ecosystem.

Many lives are undoubtedly supported by water. Furthermore, aquatic creatures are those that can thrive in water. They also rely on water for food, shelter, reproduction, and a variety of other life functions. This particular article will offer you a fair idea of the types of aquatic ecosystems and their importance in brief!

What is the Aquatic Ecosystem?

The aquatic ecosystem definition states it is a water-based environment, wherein, living organisms interact with both physical and chemical features of the environment. These living creatures whose food, shelter, reproduction, and other essential activities depend on a water-based environment are known as aquatic organisms.

Water plays a significant role in the management of world-scale ecosystem processes in aquatic systems, connecting the atmosphere, lithosphere, and biosphere by transferring material between them and allowing chemical reactions to occur. Water has unique physicochemical features that reflect the water body's quality. The physicochemical characteristics of an aquatic ecosystem determine how well it functions and how long it can support life forms. In the same way as sediments in terrestrial ecosystems provide substrate, nutrients, and a home for live aquatic resources, sediments in aquatic ecosystems are equivalent to the soil in terrestrial ecosystems. Sediments are significant catalysts in environmental food cycles and the two water quality dynamics.

The quality of sediment has a direct or indirect impact on the functioning of an aquatic ecosystem. The many physicochemical properties of sediment determine its quality. Similarly, the biotic mix of an aquatic environment determines how well it functions. In the aquatic environment, they serve as a trophic level and a source of energy. Fish have a significant ecological role in the whole food web at the trophic level.

Some of the most common aquatic organisms are – nekton, plankton, and benthos. Additionally, lakes, oceans, ponds, rivers, swamps, coral reefs, wetlands, etc. are a few popular aquatic ecosystem examples.

Features of Aquatic Ecosystem 

Salient features of the aquatic ecosystem are highlighted in this figure below –

Freshwater or saltwater can be used to make them.

They serve as a home for a variety of aquatic animals.

The majority of the vegetation is made up of algae and corals.

They have a lot of biological diversity, which makes them the most productive and wealthiest ecosystems on the planet.

They help regulate the hydrological cycle and act as a pollution filter, among other things.

Types of Aquatic Ecosystem

In general, there are two types of aquatic ecosystems, namely marine ecosystems and freshwater ecosystems. Both marine and freshwater ecosystems are further divided under different aquatic ecosystems.

Let’s Take a Look at the Aquatic Ecosystem and its Types Below.

Marine Water Ecosystem

This particular ecosystem is the largest aquatic ecosystem and covers over 70% of the earth’s total surface. This ecosystem is relatively more concentrated in terms of salinity. Nonetheless, the body of aquatic organisms is well-adjusted to saline water, and they may find it challenging to survive in freshwater. The following categories comprise the marine ecosystem. 

(Image will be Uploaded soon)

Ocean Ecosystem  

Pacific Ocean, Atlantic Ocean, Indian Ocean, Arctic Ocean, and the Southern Ocean are the five major oceans on earth. Notably, the Pacific Ocean is the largest and deepest of these five, while the Atlantic is the second largest in terms of size. Also, the Southern Ocean harbors the largest population of Krill among them. Other than that, the oceans serve as home to aquatic organisms like – turtles, crustaceans, plankton, corals, shellfish, blue whale, sharks, tube worms, reptiles, etc. 

Estuaries  

Typically, it is the meeting point of a sea and rivers, which makes the water slightly more saline when compared to freshwater and more diluted when compared to the marine ecosystem. Biologically, estuaries are considered to be productive as they stimulate primary production and trap plant nutrients. Some examples of estuaries include – tidal marshes, river mouth, and coastal bays.

Coral Reefs

These are fondly referred to as the Rain Forest of Oceans as they harbor a wide diversity of aquatic flora and fauna.  A coral reef is an aquatic ecosystem made up of corals that form reefs. Coral polyps are held together by calcium carbonate in the formation of reefs. Stony corals, whose polyps cluster in groups, make up the majority of coral reefs.

The animal phylum Cnidaria includes sea anemones and jellyfish, and coral is part of the class Anthozoa. Corals secrete hard carbonate exoskeletons that support and protect them, unlike sea anemones. Warm, shallow, clear, sunny, agitated water is ideal for most reefs. At the beginning of the Early Ordovician, 485 million years ago, coral reefs displaced the Cambrian's microbial and sponge reefs.

Coastal Ecosystem  

Coastal ecosystems are formed when land and water meet. The structure, variety, and energy flow of these ecosystems are all unique. The bottom of the coastal environment is dominated by plants and algae. Insects, snails, fish, crabs, shrimp, lobsters, and other animals make up the fauna. It is one of the major aquatic ecosystems and is quite distinct in terms of structure and diversity. The coastal ecosystem is formed in the union of land and water. Coastal ecosystems harbor a variety of plants and algae and serve as a home to snails, shrimps, crabs, lobsters, and fish. 

Freshwater Ecosystem

This aquatic ecosystem covers less than 1% of the earth’s surface and is broadly divided into – wetlands, lentic and lotic ecosystems. 

Swamps and Wetlands

These are marshy areas that are often covered in water and harbor a variety of flora and fauna. Wetlands are known to be a home of water lilies, marshes, swamps, Northern Pikes, dragonflies, Green Heron, etc.

Lentic Ecosystems

It includes standing water bodies like ponds and lakes and is a home to both floating and rooted plants, algae, and invertebrates . All standing water habitats, such as lakes and ponds, are included in lentic ecosystems. Algae, rooted and floating-leaved plants, and crustaceans like crabs and shrimp live in these habitats. Frogs and salamanders, as well as reptiles like alligators and water snakes, can be found here. Salamanders, frogs, water snakes, and alligators are commonly found in lentic ecosystems. 

Lotic Ecosystems

These aquatic ecosystems are characterized by rapid flowing water moving in one direction. They are a hub of a wide variety of insects like beetles, mayflies, and stoneflies, among others. Also, it harbors species like river dolphins, beavers, otters, eel, minnow, and trout. 

Functions of Aquatic Ecosystem  

These pointers highlight the importance of aquatic ecosystem -

Facilitates recycling of nutrients

Helps to purify water

Recharges groundwater

Is a habitat for aquatic flora and flora

Mitigates flood

FAQs on Aquatic Ecosystem

1. What is the Definition of an Aquatic Ecosystem?

It is a water-based environment, wherein living organisms inhabit with each other and their surroundings to survive. Planktons, nektons and benthos are the three broad categories of organisms living in aquatic ecosystems.

2. What are the Characteristics of Aquatic Ecosystems.

Characteristics of aquatic ecosystems can be divided into abiotic and biotic factors. The abiotic factors include depth, nutrient, temperature, salinity, flow, temperature, etc., while the biotic factors comprise the living organisms.

3. State two Functions of the Aquatic Ecosystem.

Two of the functions of the aquatic ecosystem, and its types include – i. It helps to recycle nutrients and purify water. ii. It helps to recharge the groundwater level.

4. What factors have an impact on all aquatic ecosystems?

Water flow rate, salinity, acidity, oxygen, light levels, depth, and temperature are all factors that affect aquatic habitats. Predation and photosynthesizing plants are affected by light levels.

5. What effect does temperature have on aquatic life?

Temperature has an impact on water chemistry, thus it's also significant. Warm water carries less dissolved oxygen than cool water, and certain forms of aquatic life may not be able to survive without it. At warmer temperatures, some substances become more harmful to aquatic life. Introduction of Aquatic Ecosystem

Biology • Class 12

A large fish proves more than a mouthful for a hungry great egret, which lost its prize soon after this shot was snapped. This big bird may be seen across much of the globe, but is nearly always found near water where food is plentiful.

Aquatic Ecosystems

Aquatic ecosystems connect people, land and wildlife through water.

Wetlands, rivers , lakes, and coastal estuaries are all aquatic ecosystems—critical elements of Earth’s dynamic processes and essential to human economies and health.

Wetlands connect land and water, serving as natural filters, reducing pollution , controlling floods , and acting as nurseries for many aquatic species. Rivers, lakes, and estuaries serve as important transportation, recreation, and wildlife hubs.

Learning more about the ecosystems within your watershed—all the water in your region that drains to the same point—can help you better understand how everything is connected and what is at stake with freshwater overuse, pollution, and drought.

Related Topics

• FRESH WATER
• WATER POLLUTION
• ENVIRONMENT AND CONSERVATION

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• Biology Article

Ecosystem Definition

“An ecosystem is defined as a community of lifeforms in concurrence with non-living components, interacting with each other.”

What is an Ecosystem?

An ecosystem is a structural and functional unit of ecology where the living organisms interact with each other and the surrounding environment. In other words, an ecosystem is a chain of interactions between organisms and their environment. The term “Ecosystem” was first coined by A.G.Tansley, an English botanist, in 1935.

Read on to explore the structure, components, types and functions of the ecosystem in the notes provided below.

Structure of the Ecosystem

The structure of an ecosystem is characterised by the organisation of both biotic and abiotic components. This includes the distribution of energy in our environment . It also includes the climatic conditions prevailing in that particular environment. 

The structure of an ecosystem can be split into two main components, namely: 

Biotic Components

Abiotic components.

The biotic and abiotic components are interrelated in an ecosystem. It is an open system where the energy and components can flow throughout the boundaries.

Biotic components refer to all living components in an ecosystem.  Based on nutrition, biotic components can be categorised into autotrophs, heterotrophs and saprotrophs (or decomposers).

• Producers include all autotrophs such as plants. They are called autotrophs as they can produce food through the process of photosynthesis. Consequently, all other organisms higher up on the food chain rely on producers for food.
• Primary consumers are always herbivores as they rely on producers for food.
• Secondary consumers depend on primary consumers for energy. They can either be carnivores or omnivores.
• Tertiary consumers are organisms that depend on secondary consumers for food.  Tertiary consumers can also be carnivores or omnivores.
• Quaternary consumers are present in some food chains . These organisms prey on tertiary consumers for energy. Furthermore, they are usually at the top of a food chain as they have no natural predators.
• Decomposers include saprophytes such as fungi and bacteria. They directly thrive on the dead and decaying organic matter.  Decomposers are essential for the ecosystem as they help in recycling nutrients to be reused by plants.

Abiotic components are the non-living component of an ecosystem.  It includes air, water, soil, minerals, sunlight, temperature, nutrients, wind, altitude, turbidity, etc. 

Functions of Ecosystem

The functions of the ecosystem are as follows:

It regulates the essential ecological processes, supports life systems and renders stability.

It is also responsible for the cycling of nutrients between biotic and abiotic components.

It maintains a balance among the various trophic levels in the ecosystem.

It cycles the minerals through the biosphere.

The abiotic components help in the synthesis of organic components that involve the exchange of energy.

So the functional units of an ecosystem or functional components that work together in an ecosystem are:

• Productivity –  It refers to the rate of biomass production.
• Energy flow – It is the sequential process through which energy flows from one trophic level to another. The energy captured from the sun flows from producers to consumers and then to decomposers and finally back to the environment.
• Decomposition – It is the process of breakdown of dead organic material. The top-soil is the major site for decomposition.
• Nutrient cycling –  In an ecosystem nutrients are consumed and recycled back in various forms for the utilisation by various organisms.

Types of Ecosystem

An ecosystem can be as small as an oasis in a desert, or as big as an ocean, spanning thousands of miles. There are two types of ecosystem:

Terrestrial Ecosystem

Aquatic ecosystem.

Terrestrial ecosystems are exclusively land-based ecosystems. There are different types of terrestrial ecosystems distributed around various geological zones. They are as follows:

Forest Ecosystem

Grassland ecosystem, tundra ecosystem, desert ecosystem.

A forest ecosystem consists of several plants, particularly trees, animals and microorganisms that live in coordination with the abiotic factors of the environment. Forests help in maintaining the temperature of the earth and are the major carbon sink.

In a grassland ecosystem, the vegetation is dominated by grasses and herbs. Temperate grasslands and tropical or savanna grasslands are examples of grassland ecosystems.

Tundra ecosystems are devoid of trees and are found in cold climates or where rainfall is scarce. These are covered with snow for most of the year. Tundra type of ecosystem is found in the Arctic or mountain tops.

Deserts are found throughout the world. These are regions with little rainfall and scarce vegetation. The days are hot, and the nights are cold.

Aquatic ecosystems are ecosystems present in a body of water. These can be further divided into two types, namely:

Freshwater Ecosystem

Marine ecosystem.

The freshwater ecosystem is an aquatic ecosystem that includes lakes, ponds, rivers, streams and wetlands. These have no salt content in contrast with the marine ecosystem.

The marine ecosystem includes seas and oceans. These have a more substantial salt content and greater biodiversity in comparison to the freshwater ecosystem.

Also check: Habitat Diversity

Important Ecological Concepts

1. food chain.

The sun is the ultimate source of energy on earth. It provides the energy required for all plant life. The plants utilise this energy for the process of photosynthesis, which is used to synthesise their food.

During this biological process, light energy is converted into chemical energy and is passed on through successive trophic levels. The flow of energy from a producer, to a consumer and eventually, to an apex predator or a detritivore is called the food chain.

Dead and decaying matter, along with organic debris, is broken down into its constituents by scavengers. The reducers then absorb these constituents. After gaining the energy, the reducers liberate molecules to the environment, which can be utilised again by the producers.

2. Ecological Pyramids

An ecological pyramid is the graphical representation of the number, energy, and biomass of the successive trophic levels of an ecosystem. Charles Elton was the first ecologist to describe the ecological pyramid and its principals in 1927.

The biomass, number, and energy of organisms ranging from the producer level to the consumer level are represented in the form of a pyramid; hence, it is known as the ecological pyramid.

The base of the ecological pyramid comprises the producers, followed by primary and secondary consumers. The tertiary consumers hold the apex. In some food chains, the quaternary consumers are at the very apex of the food chain.

The producers generally outnumber the primary consumers and similarly, the primary consumers outnumber the secondary consumers. And lastly, apex predators also follow the same trend as the other consumers; wherein, their numbers are considerably lower than the secondary consumers.

For example, Grasshoppers feed on crops such as cotton and wheat, which are plentiful. These grasshoppers are then preyed upon by common mouse, which are comparatively less in number. The mice are preyed upon by snakes such as cobras. Snakes are ultimately preyed on by apex predators such as the brown snake eagle.

In essence:

3. Food Web

Food web is a network of interconnected food chains. It comprises all the food chains within a single ecosystem. It helps in understanding that plants lay the foundation of all the food chains. In a marine environment, phytoplankton forms the primary producer.

Main article:   Food web

To learn more about what is an ecosystem, its structure, types, components, and functions, register at BYJU’S website or download the BYJU’S app.

Frequently Asked Questions

1. what is the ecosystem.

The ecosystem is the community of living organisms in conjunction with non-living components of their environment, interacting as a system.

2. What are the different types of ecosystems?

The different types of the ecosystem include:

• Forest ecosystem
• Grassland ecosystem
• Desert ecosystem
• Tundra ecosystem
• Freshwater ecosystem
• Marine ecosystem

3. What are the functional components of an ecosystem?

The four main components of an ecosystem are: (i) Productivity (ii) Decomposition (iii) Energy flow (iv) Nutrient cycling

4. Which ecosystem do we live in?

We live in a terrestrial ecosystem. This is the ecosystem where organisms interact on landforms. Examples of terrestrial ecosystems include tundra, taigas, and tropical rainforests. Deserts, grasslands and temperate deciduous forests also constitute terrestrial ecosystems.

5. What is the structure of the ecosystem?

The structure of the ecosystem includes the organisms and physical features of the environment, including the amount and distribution of nutrients in a particular habitat. It also provides information regarding the climatic conditions of that area.

6. Which is the largest ecosystem in the world?

The largest ecosystem in the world is the aquatic ecosystem. It comprises freshwater and marine ecosystems. It constitutes 70% of the surface of the earth.

7. What is the major function of an ecosystem?

The ecosystem is the functional unit of the environment system. The abiotic components provide the matrix for the synthesis of organic components. This process involves the exchange of energy.

8. What makes a good ecosystem?

A good ecosystem consists of native plants and animal species interacting with each other and the environment. A healthy ecosystem has an energy source and the decomposers that break down dead plants and animal matter, returning essential nutrients to the soil.

9. What all include the non-living things in an ecosystem?

The non-living things in an ecosystem include air, wind, water, rocks, soil, temperature and sunlight. These are known as the abiotic factors of an ecosystem.

Register at BYJU’S for ecosystem notes or other important study resources.

Further Reading:

• Our Environment
• Energy Flow In Ecosystem
• What Is A Natural Ecosystem?
• Why Is The Ecosystem Important?
• What Are The Five Levels Of Ecology?
• What Are The Different Fields Of Ecology?
• What Are The Three Environmental Issues?
• Difference Between Food Chain And Food Web
• How Many Types Of The Ecosystem Are There?
• How Can We Improve Our Environmental Health?

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As waterbodies lose oxygen, are we breaching a potential planetary boundary?

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• A new perspective piece argues that aquatic deoxygenation — the depletion of oxygen in marine and freshwater environments — should be considered its own “boundary” in the planetary boundary framework first proposed by scientists in 2009. Human-caused nitrogen pollution and climate change have greatly worsened aquatic deoxygenation worldwide.
• The planetary boundary framework defines nine natural biophysical and biochemical system processes that maintain the resilience of the Earth system, allowing life to thrive. But each boundary includes limits within which humanity needs to safely operate.
• The paper’s lead author says that increased scientific understanding of dissolved oxygen in marine and freshwater environments shows that it regulates, and is regulated by many of the other planetary processes, which in turn warrants the inclusion of aquatic deoxygenation in the planetary boundary framework.
• The framework is a rapidly evolving theory. Whether aquatic deoxygenation is already indirectly taken into account by the existing framework, as some argue, or whether it should be considered as its own planetary boundary remains to be determined.

The Earth is in crisis — a reality made increasingly clear by intensifying heat, drought and storms, worsening pollution, land stripped of forests, and the ramping up of the sixth great extinction . But some scientists say we’re failing to prioritize a critical Earth change that is accelerating in the modern world and that helped drive past global extinction events: aquatic deoxygenation.

In 2023, scientists suggested that anoxia, the lack of dissolved oxygen in a water body, played an important role in ocean ecosystem disruption and extinctions during the Triassic-Jurassic mass extinction around 200 million years ago, while others say it contributed to the “ great dying ” of the Permian extinction 50 million years earlier, which wiped out 90% of all marine species.

Today, human-caused hypoxia (reduced oxygen levels), due increasingly to synthetic agricultural fertilizer pollution and climate change, annually helps create vast dead zones in the Gulf of Mexico , Baltic Sea , East China Sea , and estuaries, lakes and streams around the globe.

Now, a new perspective piece in Nature Ecology & Evolution seeks to add aquatic deoxygenation of both fresh- and saltwater ecosystems to the planetary boundary framework, a theory currently used to define the safe operating limits for Earth’s natural systems.

Natural systems out of balance

In 2009, a team of international scientists proposed the planetary boundary framework , a theory defining nine interconnected biophysical and biochemical processes: natural systems that regulate Earth’s stability and resilience and make life as we know it possible. The researchers also tried to identify metrics for the human stressors reshaping and degrading those natural processes today.

According to the theory, each of the nine processes needs to stay within certain limits, referred to as “boundaries,” to maintain “the safe operating space” for humanity. But human activities over the past 150 years have pushed hard up against these boundaries, and toward dangerous Earth system tipping points — thresholds that, if violated, could threaten life.

The nine currently identified boundaries include climate change, biosphere integrity (incorporating biodiversity loss), ocean acidification , stratospheric ozone depletion , atmospheric aerosol pollution , freshwater change , biogeochemical flows of nitrogen and phosphorus , land-system change , and release of novel entities (including pollution by tens of thousands of synthetic chemicals).

A 2015 study , published by many of the same authors, found that humanity was already operating outside the safe operating space for four of the boundaries: climate change, biosphere integrity, land-system change, and biogeochemical flows. In 2023, this was further updated by the same core team who reassessed all nine boundaries, adding more control variables and sub-boundaries. They found that humanity had transgressed the safe operating space for six boundaries, adding novel entities and freshwater change.

The argument for a 10th boundary

In July 2024, a separate team of scientists, none of them involved in the original planetary boundaries research, argued in Nature Ecology & Evolution that aquatic deoxygenation should be adopted as an additional, 10th boundary.

Deoxygenation in both freshwater and marine ecosystems is critically impacting the integrity of Earth’s ecological and social systems today, the authors wrote, adding that the planet’s aquatic habitats are approaching critical oxygen thresholds “at rates comparable to other planetary boundary processes.” Furthermore, aquatic oxygenation isn’t an independent process, but “regulates and responds to ongoing changes in other planetary boundary processes.”

Lead author Kevin Rose told Mongabay in an interview that when the planetary boundary theory was proposed in 2009, there wasn’t a lot of compiled data on dissolved oxygen. However, he said, the growth of scientific knowledge and understanding of the issue of deoxygenation, and its “implications for habitability, sustainability of freshwaters, coastal systems and the open oceans,” warrants its inclusion in the planetary boundary framework now as a 10th boundary.

“In aquatic environments, dissolved oxygen concentrations have largely been declining for, in some cases, decades to centuries,” Rose said. “There’s a number of factors driving this, but one of the things that’s come out in the last few years is the scale at which we’re losing dissolved oxygen and aquatic ecosystems, as well as its implications for [interacting with and impacting] a lot of the other planetary boundaries.”

The authors wrote that dissolved oxygen concentrations have “rapidly and substantially declined across both freshwater and marine habitats, ranging from small ponds to large lakes and reservoirs, rivers, inland seas, estuaries, and areas of the coastal and open ocean.”

They note that lakes and reservoirs have experienced oxygen losses of 5.5% and 18.6% respectively since 1980, and that the global ocean overall has experienced a 2% loss in oxygen since 1960. While marine deoxygenation appears lower than that of freshwater, this loss is “far more geographically and volumetrically extensive,” according to the authors.

Rose noted that oxygen availability in aquatic environments regulates, and is regulated by, other planetary boundaries through a “give and take” process. For instance, an interplay between the climate change boundary and the aquatic deoxygenation boundary takes place when anoxic forms of respiration take over in deoxygenated marine and freshwater environments, which can produce methane. “That [results in] an important feedback to climate change, because methane is a really potent greenhouse gas,” Rose said.

Deoxygenation doesn’t only interact with the climate change boundary. The study authors wrote that it also interacts in a major way with the land-system change, biogeochemical flows, and biosphere integrity boundaries. For example, increased biogeochemical flows of nitrogen and phosphorous, due largely to fertilizer runoff, contribute to red tides and falling oxygen levels in the world’s estuaries, and the resulting biodiversity declines occurring in these dead zones.

An evolving theory

Johan Rockström , director of the Potsdam Institute for Climate Impact Research and one of the originators of the planetary boundary frameworks, said in a recent Q&A with Mongabay that the planetary boundary theory is robust and continues to evolve.

In the future, he said, he believes each planetary boundary could include up to four control variables — features linked to and influencing a particular boundary — to better emulate the complexity of Earth systems.

While not specifically commenting on the new study led by Rose, Rockström also noted that the ocean planetary boundary currently only has one quantified control variable — ocean acidification — which he said is inadequate for describing marine complexities.

“That is scientifically and operationally very unsatisfying,” Rockström told Mongabay. For example, “We presently have no control variable for the biology in the ocean. So, there is a quest to find a twin control variable that can capture biology there — all phytoplankton, zooplankton, the food webs and the nutrient cycling in the ocean, so we’ll not only be able to [evaluate] the heat and chemistry of the ocean as we do today, but changes in biology too.

“Having multiple control variables for each boundary not only shows us the complexity of the Earth system,” Rockström concluded, “ but also [gives] us multiple ways of measuring the planetary boundary process.”

It therefore seems reasonable that aquatic deoxygenation could eventually figure into planetary boundary refinements, possibly as an additional control variable for the ocean planetary boundary, which is currently described as the ocean acidification boundary.

Lan Wang-Erlandsson, a researcher at the planetary boundaries research lab at the Stockholm Resilience Centre, who was not involved in the new paper led by Rose, said she believes that previous planetary boundaries assessments already indirectly include aquatic deoxygenation, but that it could be considered as a control variable for other boundaries.

“I think the original scope of the nine planetary boundaries should be able to capture key transgressions driven by deoxygenation, at least indirectly. Especially as the specific variable used to represent the boundaries can be (and have been) revised to keep up with scientific advances,” Wang-Erlandsson told Mongabay in an email.

On the other hand, Wang-Erlandsson said she doesn’t have an opinion as to whether aquatic deoxygenation should be considered its own planetary boundary.

“Regardless, I think the issues raised by the authors are urgent and important,” Wang-Erlandsson said, adding she finds “their suggestions for future research valuable and relevant for better understanding Earth system resilience and sustainability.”

Banner image: A sea turtle in Ningaloo Reef, Australia. Image by Emilie Ledwidge / Ocean Image Bank .

Warmer, oxygen-poor waters threaten world’s ‘most heavily exploited’ fish

Richardson, K., Steffen, W., Lucht, W., Bendtsen, J., Cornell, S. E., Donges, J. F., … Rockström, J. (2023). Earth beyond six of nine planetary boundaries. Science Advances, 9 . doi: 10.1126/sciadv.adh2458

Rockström, J., Steffen, W., Noone, K., Persson, Å., Chapin, F. S., Lambin, E. F., … Foley, J. A. (2009). A safe operating space for humanity. Nature, 461 (7263), 472-475. doi: 10.1038/461472a

Rose, K. C., Ferrer, E. M., Carpenter, S. R., Crowe, S. A., Donelan, S. C., Garçon, V. C., … Breitburg, D. (2024). Aquatic deoxygenation as a planetary boundary and key regulator of earth system stability. Nature Ecology & Evolution, 8 (8), 1400-1406. doi: 10.1038/s41559-024-02448-y

Steffen, W., Richardson, K., Rockström, J., Cornell, S. E., Fetzer, I., Bennett, E. M., … Sörlin, S. (2015). Planetary boundaries: Guiding human development on a changing planet. Science, 347 (6223), 1259855. doi: 10.1126/science.1259855

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Milton Ranch Restoration: A Case Study for Successful Collaboration 

There are many benefits that come from the restoration of prairie systems. And collaboration is key to making it happen. 

Growing up, Bill Milton split his time between the Bay Area and his father’s ranch near Helena, Montana. After his father passed away, he wandered around for a time, before returning to Montana. In 1978, Bill and his wife Dana bought a ranch, now known as Milton Ranch, just north of Roundup, Montana. The Milton’s made a home on the ranch where they raised their three children. 

Milton Ranch is 15,000 acres, and sits within the largest intact grassland ecosystem in the world. The grasslands are home to antelope, deer, elk, and prairie dogs. Many birds visit the ranch as well, including ducks and geese, white pelicans and cormorants, and bird species of concern like the Sprague’s pipit. While some of the land was previously farmed, a majority of those fields have since been returned to native grasses, and the Milton’s continue to do the same to the remaining non-native fields. Over 400 cow-calf pairs graze on the grasses. About two thirds of the Milton ranch is deeded land, and the remaining third is leased from the Bureau of Land Management (BLM) and the State of Montana.  

When asked about his favorite time to be on the land, Bill Milton shared, “All the time. I love early mornings, and all the different lights at different times of the day. When you work on land, there is an interdependence going on. Over the years you see how the grasses and animals change. When you are here for a long time, you pick up on those differences and see subtleties that someone who just showed up wouldn't notice.”  

The Milton’s take a holistic approach to land management, recognizing the positive relationship that is possible between cows and the landscape they live on. This holistic approach involves moving the cows frequently, often daily, to provide short but intense grazing periods to the cows and long recovery periods to the grasslands.  

Close to ten miles of ephemeral stream runs through the center of Milton Ranch. The creek is an unnamed tributary of Willow Creek, and a part of the Musselshell Watershed. The Milton’s understand that rivers do not stop at fence lines or jurisdictional boundaries, and that land management shouldn’t either. To better steward their ranch, the Milton family is teaming up with the BLM,  National Wildlife Federation (NWF), and Anabranch Solutions , a small riverscape restoration business, to carry out restoration on the creek.  

Due to the holistic management techniques already in practice on the ranch, the riparian areas are in fairly good shape. To help maintain the health of the riparian areas, they are not grazed during peak growing season more than once every four years. That gives riparian vegetation three out of every four years to build root mass and take advantage of available moisture. However, there is still an opportunity to improve the health of these riparian areas. As central Montana becomes more arid, conserving water resources is an important part of maintaining resilience. 

Shelby Weigand, senior coordinator for riparian connectivity at NWF said “although Milton Ranch experienced intense grazing and stream modification in the past, due to improved grazing practices, it is on an upward trend. We want to continue that upward movement.”  

To help maintain water resources and increase resilience, partners are working to restore the creek on Milton Ranch. The goal of the restoration project is to connect the floodplain, maintain flows in the creek later into the year, and improve native vegetation along the creek. The project will involve installing beaver dam analogs, and post-assisted log structures, which cause water to slow down and spread out. Partners will also plant woody vegetation such as buffaloberry, chokecherry, and willow, that will be fenced in so the plants can be used as seed or rhizome banks. 

While some of the work will happen on Milton Ranch, it will also improve the creek on BLM and State of Montana owned land. Shane Trautner, rangeland management specialist for the BLM field office in Billings, has worked on previous stewardship projects with the Miltons, and he is pleased to be partnering with them again. Trautner was tasked with collecting woody material to use for the structures. He is collaborating with BLM’s hazardous fuels crews to get woody material from thinning projects in the area. Some of the material will come from the Milton Ranch, and the remainder will be sourced twenty miles west of the site. Materials will be collected and staged close to the date of implementation, so they are malleable and easy to build with.  

During project implementation, NWF will be hosting a workshop to discuss the benefits of restoration in prairie systems. Weigand and Trautner hope that while the Milton Ranch may be the starting point for restoration in the Musselshell Watershed, it can also be a catalyst for future projects.  

“This is about more than just Bill’s place,” said Trautner. “Ultimately the goal is to expand and use collective resources to keep building and fine tuning from here. I want to document real change in the watershed.” 

Bill Milton agrees, noting that “these restoration projects are good for everybody. It is good for ranchers to have partnerships and organizations to tell a good story to increase appreciation for ranching and how it can be beneficial for landscapes. Collaboration is our superpower.”  

About the Author 

Rose Vejvoda is a graduate student at Northern Arizona University, where she is a candidate for a Professional Master of Science in Climate Science and Solutions, and a graduate certificate in Greenhouse Gas Accounting. Rose received her undergraduate degree from Montana State University where she studied English Writing, and Sustainability Studies. She has a passion for using effective storytelling to build relationships, uplift local communities, and help people feel connected to the natural world. Rose wrote this story while she was a Freshwater Ecosystems Intern at Natural Resources Defense Council working with BLM.  

Rose Vejvoda, Intern

Montana/Dakotas State Office

5001 Southgate Drive Billings , MT 59101 United States

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