Biological
evolution seems to involve a kind of innovation, whereby novel adaptations or
mutations sometimes appear when needed. There are epigenetic examples where a
default state reverts to an alternative state with a different gene expression
under certain conditions and back to the default state when the conditions
change. Adaptation can be seen as a form of biological engineering. On a
different scale and scope, there are activities among certain species that can
be called ecosystem engineering. Probably the most common example is that of
beavers constructing their dams that create and maintain these engineered
ecosystems.
How does ecosystem engineering
differ from ecological engineering? Ecosystem engineering might be seen as
“natural” ecosystem change according to animal instinct, while ecological
engineering might be seen as specific human endeavors consciously planned and
executed to change ecosystems. The word “ecological” refers to the “study of”
ecology, such study being a uniquely human endeavor. Perhaps a better way to
describe both is as forms of “niche construction,” which is defined in
Wikipedia as follows:
“Niche construction is the ecological process by which
an organism alters its own (or another species') local environment. These
alterations can be a physical change to the organism's environment, or it can
encompass the active movement of an organism from one habitat to another where
it then experiences different environmental pressures. Examples of niche
construction include the building of nests and burrows by animals, the creation
of shade, the influencing of wind speed, and alternations to nutrient cycling
by plants. Although these modifications are often directly beneficial to the
constructor, they are not necessarily always. For example, when organisms dump
detritus, they can degrade their own local environments. Within some biological
evolutionary frameworks, niche construction can actively beget processes
pertaining to ecological inheritance whereby the organism in question
"constructs" new or unique ecologic, and perhaps even sociologic
environmental realities characterized by specific selective pressures.”
After observing nature as a human,
I have often made the statement that “nature is an opportunist.” It seems that
the instinctual behavior-dominating species of non-humans are always seeking to
gain in the quest for survival and need fulfillment.
The section below is from Chapter
1 of my 2021 book, Sensible Decarbonization explores the idea of nature and the
nexus of nature and humans. Humans can be seen as beyond nature in one sense
and part of it in another. Humans’ ability to alter nature is unprecedented and
worrisome as the population continues to increase. One could perhaps say that
we also cause a lot of niche destruction, destroying habitats and stressing
species.
What is
Nature and How Do Humans Fit In?
Our concept of nature is probably
a bit different than ancient peoples’ concept of nature, especially after the
Industrial Revolution. Many of us see our inventions and technologies as
something different from nature. They are man-made, synthetic, even artificial,
which also means fake or unnatural. In a sense, we compete with nature as
creators. The lines between natural and artificial are much blurred these days.
Utilitarian philosopher John Stuart Mill emphasized our mastery over nature and
how it benefited us. Jedidiah Purdy, in his book After Nature: A
Politics of the Anthropocene, writes: “If Nature were a place, we could
not find it, If Nature were a state of mind, we could not attain it. We are
something else, and so is the world.”[1] What
I think he means is that the definition of nature is changing, especially in
relation to humans. With 7.7 billion humans inhabiting a world where we decide
which parts of nature are preserved, where we selectively breed our food, and where
we impact nature in diverse and profound ways, there is no longer a dichotomy
between humans and nature. One might say we are the biggest part of nature, the
biggest influence on nature. We are in the Age of Humans, the Anthropocene.
Just like in the deep past, the earth was once dominated by bacteria, first the
prokaryotes, cyanobacteria, and methanogens, then eukaryotes, and later plants
and animals gained influence, now it is humans that do much of the influencing.
We and all creatures evolve with our environment, altering it to improve our
chances of survival. This is known a “niche construction.” Thus, we were never
really separate from nature. It was just a convenient way of depicting things
for a time. Among conservationists, nature is no longer considered to be simply
“pristine wilderness,” notes writer Emma Marris, author in 2011 of Rambunctious
Garden: Saving Nature in a Post-Wild World.[2] We
humans have changed the composition of the atmosphere and the oceans just like
those microbes did in their heydays. Our influence on nature is everywhere. We
have moved and mixed animal and plant species all over the world. Humans are
also master manipulators of the materials of nature, creators called homo
faber, man the user of tools, man the maker of his destiny. “What humans
do is utilize nature by manipulating its materials. The material world is not
just a display of our technology and culture, it is part of us. We invented it,
we made it, and in turn it makes us who we are,” says materials scientist
and engineer Mark Miodownik, author of Stuff Matters: Exploring the
Marvelous Materials that Shape Our Man-Made World.[3] Of
course, humans are not alone in influencing nature. Many other species do it,
but usually on smaller scales, more locally, and sometimes on much slower,
evolutionary time scales. In evolutionary time, plants develop thorns and the
manufacture of poisons to dissuade local nibblers. In real-time, beavers
engineer small lakes and reroute rivers by felling trees and building dams.
Elephants root out trees to maintain grassland. Stream-dwelling shipworms eat
away at rock, which creates niche habitat for invertebrates. Squirrels plant
oak trees. Cyanobacteria were arguably the first of these ecosystem
engineers when they oxygenated the atmosphere, a global-scale effect.
A study and paper in Nature Communications from the Santa Fe
Institute attempts to quantify these ecosystem engineering, or niche
construction feats in terms of ecosystem effects.[4] Food
webs, species interactions, and extinctions were considered. A network of these
ecosystem engineers in sufficient numbers was found to increase ecosystem
stability and lead to few extinctions. They created an ecological
network model based solely on interactions where species do three
things: eat, need, and make. The model is a way to “explore the dynamics of
ecosystem assembly.” Interestingly, the article suggests that we
humans are “planetary scale {ecosystem} engineers.” Such models can aid
understanding and perhaps help quantify some ecosystem services, which
in turn can help quantify business externalities, both negative and positive,
that respectively pollute or benefit the environment. Much of our engineering,
as well as that of other species, has had unintentional environmental effects,
which is often because they were not planned with conscious, educated
consideration of possible future effects. As time goes on, we understand
impacts better. Ecosystems reorient in various ways according to inputs. If
this continues for long time periods, then evolutionary-scale interactions
between one species and another, or between a species and some part of the
environment, then evolutionary changes are possible and known to happen.
Fixation or switching on or off of gene alleles in response to environmental
conditions occurs via epigenetic changes and can happen over much shorter time
scales than natural selection. Thus, we and all species co-evolve with other
species and with our environments. We change nature. Nature changes us. We also
adapt to nature, and nature adapts to us.
We have gotten better at adapting to nature, and we have gotten better at assisting nature in adapting to us. A recent experiment revealed that by infecting a disease-carrying mosquito with bacteria and releasing it, the rates of dengue fever dropped in the Indonesian city of Yogyakarta, making it four times less likely that a person would be infected over a two-year period compared to before. Indonesia has 7 million cases of dengue per year, so this could be a big help.[5] The same mosquito also carries Zika, chikungunya, and yellow fever, so the implications could be huge. There appear to be no safety concerns with humans, so the next step is more releases. Thus far, it appears that the bacteria impair the ability to acquire the disease, and importantly, they also pass on the bacteria to their offspring, making them also unable to get dengue. However, since mosquitoes don’t travel far, there needs to be multiple releases to cover their ranges.
A 2021 article by treehugger.com notes 10 species that serve as ecosystem engineers. Either for themselves and/or for other species. They describe ecosystem engineers as follows:
“Ecosystem engineers are species that create, destroy, modify, or maintain habitats in significant ways. These uniquely productive animals create conditions for other species to benefit from, such as adequate shelter or food sources.”
They list 10 species that are ecosystem engineers: 1) Beavers divert and control streams, creating habitat for many other species, 2) Elephants make large footprint depressions, migration trails, and sometimes convert forest into grasslands, thus changing ecosystems, 3) Pecarries, related to pigs, make wallows which are utilized by many other species, increasing biodiversity in Central and South American rainforests, 4) Arctic foxes engineer soil chemistry by constructing dens to shelter pups, with urine, feces, and rotting prey enhancing local soil fertility, 5) Coral create reef structures that affect ocean currents, and create specific ocean ecosystems where a great diversity of plants and animal species thrive, 6) Kelp forests in cold coastal ocean waters also create thriving ecosystems of great biodiversity, 7) Termites enhance soil nutrient cycling, soil texture, soil aeration, and soil consolidation, 8) Red groper fish clear sand and sediment from ocean floor depressions, creating homes for themselves and many other species, 9) Woodpeckers make nesting cavities that are later used by other bird species for nesting, and 10) Prairie dogs create vast underground “towns” that other species use, such as rabbits, amphibians, snakes, and birds. They also enhance soil aeration, water infiltration, and nutrient cycling.
There are numerous other examples of niche construction in the natural world that could be considered to be ecosystem engineering.
The Wikipedia entry notes that “humans possess an unusually potent capability to regulate, construct, and destroy their environments.” It also notes that human evolution involved much niche construction, some of which is cultural, noting that “human cultural niche construction has co-directed human evolution” in a process known as gene-culture co-evolution. We are both products and creators of niche construction.
Ecological Restoration and Enhancement as Ecological Engineering
This is referring to human
endeavors like land restoration, habitat improvements, and other ways we might
engineer and construct projects to help nature thrive. With careful planning,
execution, and continued monitoring, humans can restore and enhance some
ecosystems. Even simple things like pollinator gardens can help certain species
to thrive. We can also, of course, inadvertently damage ecosystems with our
construction projects.
The Wikipedia entry for
‘Ecological engineering’ notes the following five classes and 19 design
principles of ecological engineering from Mitsch and Jorgensen’s 2003 book
‘Ecological Engineering and Ecosystem Restoration’:
Five Functional Classes for ecological engineering designs
1. Ecosystem
utilized to reduce/solve pollution problem. Example: phytoremediation,
wastewater wetland, and bioretention of stormwater to filter excess nutrients
and metals pollution
2. Ecosystem
imitated or copied to address resource problem. Example: forest restoration,
replacement wetlands, and installing street side rain gardens to extend canopy
cover to optimize residential and urban cooling
3. Ecosystem
recovered after disturbance. Example: mine land restoration, lake restoration,
and channel aquatic restoration with mature riparian corridors
4. Ecosystem
modified in ecologically sound way. Example: selective timber harvest,
biomanipulation, and introduction of predator fish to reduce planktivorous
fish, increase zooplankton, consume algae or phytoplankton, and clarify the
water.
5. Ecosystems
used for benefit without destroying balance. Example: sustainable
agro-ecosystems, multispecies aquaculture, and introducing agroforestry plots
into residential property to generate primary production at multiple vertical
levels.
Mitsch and Jorgensen identified 19 Design
Principles for ecological engineering, yet not all are expected to contribute
to any single design:
1. Ecosystem
structure & function are determined by forcing functions of the system;
2. Energy
inputs to the ecosystems and available storage of the ecosystem is limited;
3. Ecosystems
are open and dissipative systems (not thermodynamic balance of energy, matter,
entropy, but spontaneous appearance of complex, chaotic structure);
4. Attention
to a limited number of governing/controlling factors is most strategic in
preventing pollution or restoring ecosystems;
5. Ecosystem
have some homeostatic capability that results in smoothing out and depressing
the effects of strongly variable inputs;
6. Match
recycling pathways to the rates of ecosystems and reduce pollution effects;
7. Design
for pulsing systems wherever possible;
8. Ecosystems
are self-designing systems;
9. Processes
of ecosystems have characteristic time and space scales that should be
accounted for in environmental management;
10. Biodiversity
should be championed to maintain an ecosystem's self design capacity;
11. Ecotones,
transition zones, are as important for ecosystems as membranes for cells;
12. Coupling
between ecosystems should be utilized wherever possible;
13. The
components of an ecosystem are interconnected, interrelated, and form a
network; consider direct as well as indirect efforts of ecosystem development;
14. An
ecosystem has a history of development;
15. Ecosystems
and species are most vulnerable at their geographical edges;
16. Ecosystems
are hierarchical systems and are parts of a larger landscape;
17. Physical
and biological processes are interactive, it is important to know both physical
and biological interactions and to interpret them properly;
18. Eco-technology
requires a holistic approach that integrates all interacting parts and
processes as far as possible;
19. Information
in ecosystems is stored in structures.
The classes show that there are
many varieties of ecological restoration, and the design principles show that
there are many considerations of such projects.
The following graphic attempts to
show how ecological engineering relates to environmental engineering and civil
engineering.
The book Conservation Techniques, by Marci X. Meixler and Mark B. Bain, has a chapter devoted to Ecosystem engineering. They see ecosystem engineering as a broader approach than just restoration. I am using the terms restoration and enhancement to make this distinction. We are engineering ecosystems both purposely and inadvertently.
The chapter summary is given below:
“As a field, ecological engineering focuses on alleviating
ecosystem stress responses as these are symptoms of poor ecological health. In
practice, there seems to be more emphasis on collaborative goal-setting that
results in consensus on a vision for ecosystem design. The practical need to
gain public support for a new ecosystem is seen as essential for long-term
sustainability. The underlying goal of ecological engineering is to improve
degraded and abandoned environments to provide benefits to both people and
nature and this goal figures prominently in the case study. While this
environmental management technique lacks an established track record and
principles for success, there appears to be general consistency in many of the
key features of this approach.”
The following table from the book
compares expected normal vs. stressed ecosystem properties. The response of
sensitive species to ecological stress is often a major indicator of the
presence of that stress.
The following graph simply shows that ecosystem degradation is highest when ecosystem stress is highest, but it also suggests that when stresses hit a certain level, there is a faster move toward ecosystem degradation as sensitive species are replaced by tolerant species.
References:
10
Ecosystem Engineers That Create New Habitats: Ecosystem engineers create
conditions for other species to thrive in. Autumn Spanne. Treehugger. Updated
August 29, 2021. 10 Ecosystem Engineers That Create
New Habitats
Ecological
engineering. Wikipedia. Ecological engineering - Wikipedia
Ecosystem
engineer. Wikipedia. Ecosystem engineer - Wikipedia
Ecological
Engineering. Chapter 9 of Conservation Techniques, by Marci X. Meixler and Mark
B. Bain. Rutgers Universal Libraries. Ecological
Engineering – Conservation Techniques
Niche
construction. Wikipedia. Niche construction - Wikipedia
[1] Purdy, J. (2015). After Nature: A Politics of the Anthropocene. Harvard University Press.
[2] Maris, E. (2011). Rambunctious Garden: Nature in a Post-Wild World. Bloomsbury.
[3] Miodownik, M. (2015). Stuff Matters: Exploring the Marvelous Materials that Shape Our Man-Made World. Mariner.
[4]
Yeakel, J. D., Pires, M. M., & Gross, T. (2020, July 3). Diverse
Interactions and Ecosystem Engineering Can Stabilize Community Assembly. Nature
Communications (11).
5] Sanders, R. (2020, August 26). Breakthrough in eliminating dengue, other mosquito-borne diseases. Berkeley News. Retrieved from https://news.berkeley.edu/2020/08/26/breakthrough-in-eliminating-dengue-other-mosquito-borne-diseases/
[6] Oury, J.-P. (2020, July 13). Viewpoint: Activist opposition to GMOs fueled by an 'extremist' vision of nature. Genetic Literacy Project. Retrieved from https://geneticliteracyproject.org/2020/07/13/viewpoint-activist-opposition-to-gmos-fueled-by-an-extremist-vision-of-nature/
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