This is an excerpt from my 2021 book Sensible Decarbonization: Regulation, Risk, and Relative Benefits in Different Approaches to Energy Use, Climate Policy, and Environmental Impact
Humans have long altered the environment in significant
ways. Agriculture itself is a form of terraforming, or planet altering, as well
as a form of geoengineering. It has probably altered the climate, argues
William Ruddiman in Plows, Plagues, and
Petroleum: How Humans Took Control of the Climate. He suggests that early
farming and burning for agriculture, and their slow-down in times of plague,
affected atmospheric CO2 and methane levels on a small but measurable scale.[1]
Soil degradation, loss of soil fertility, soil erosion, and/or salt
accumulation due to long-term irrigation from agriculture is well documented by
Sumerians in the third millennium B.C. as well as in Ancient Greece and Rome,
the Americas and China and possibly anywhere one investigates early urban
farming sites. Overgrazing led to loss of plant mass in dry areas. Population
increase led to farming slopes which increased soil erosion and led to
over-sedimentation in valleys.[2]
Early farmers moved in small groups to farm new land. Mobile herders could be
less destructive by moving their herds seasonally to more ideal pasture.
Farming led to larger settled populations which robbed the local soil fertility
through time. Large city-states could become sensitive to such environmental
degradations which often meant famine and scarcity. Overhunting of megafauna by
early Native Americans and Native Australians before them, might be another
example. Late in the first millennium of the common era Maoris arrived in New
Zealand and proceeded to burn down much of the forest and hunt moa birds to
extinction. The use of fire on a significant scale to assist agriculture and
game hunting is well documented. Domestication of animals is also a fundamental
way in which humans have altered their environment. Both agriculture and
livestock development improved the health and lifespans of humans and increased
population. Downsides were soil degradation and the development of diseases
which could pass from livestock to humans. Even though the human suffering was
very significant the overall affect was decidedly positive.
Even in pre-Industrial
Europe people had to endure environmental problems. Sewage in cities
contaminated water. Smoke from cooking and heating fires burning wood and coal
made indoor and outdoor air pollution. Animal manure contaminated the streets
and made them stink. The streets were used as latrines. Animal carcasses and
mass burials of poor people contributed to the stench. Bacterial stomach
infections, intestinal worms, and in some places, malaria, were common. The
Thames River of today is now cleaner than it was in pre-Industrial times.
It is true
that we can now alter nature through technology on scales unheard of in the
past which requires greater attention to potential impacts. It is also true
that we can use technology to significantly reduce those impacts. In modern
times there are many synthetic chemicals in the environment and plastics,
including micro-plastic fibers. Even so, most of those chemicals and plastics
offer far more benefits than harms. Thus, mitigating plastic pollution is a
more sensible regulatory philosophy than banning plastic or in some cases even
limiting plastic use. One of the best ways to do that is to improve waste
management practices and infrastructure in developing countries, where the vast
majority of ocean plastic originates. We also alter nature more often and in
more places in response to population growth. This increases habitat loss as
vital forests are lost or fragmented. Deforestation is a serious problem in the
tropics, especially in the Amazon. There it is usually slash-and-burn clearing
for agriculture and grazing. It is less of a problem in temperate climates,
many of which have been seeing annual net reforestation for many years now. The
initial deforestation in Europe and the U.S. was caused by using wood for fuel
and building, over many centuries in Europe but only a few in the U.S. That net
reforestation is expected to continue. Many countries are in process or have
plans for massive tree planting to help mitigate climate change. Past
deforestation has also contributed to net soil erosion. Soil is always being
formed and it is always eroding, the amounts of each being in a net general
balance. Millenia of deforestation and plowing agriculture, particularly on
slopes, has led to net soil erosion. Deforestation due to growing populations
and their need to heat, cook, and build with wood and clear forests for
agriculture and grazing caused the net deforestation that lowered terrestrial
carbon uptake. Much is being done now to reverse that, like highly efficient,
smart, and intensive agriculture, less tilling, and biotech that leads to
higher yields requiring less land disturbance. The increased CO2 in the
atmosphere contributes to global greening or more simply, improved plant
growth, that aids carbon uptake. This CO2 fertilization effect is a desirable
negative feedback of increased atmospheric CO2.
Commenting on
an online friend’s post the other day he referred to my comments as rather
anthropocentric. I replied that that was a fair enough assessment. Should we be
nature-centric or human-centric? I would say both but being human-centric is
probably a priority. Is this selfishness at the expense of nature? It can be
but in most cases the human-centric approach can have so many more benefits
that the costs and impacts are worth it and can be reduced through time. To be
human-centric is self-interest, hopefully an enlightened self-interest. It is
also species-centric which includes considering future generations of humans.
Indeed, it can be argued that being human-centric cannot really be separated
from being nature-centric since we are a part of nature too, the most
influential part these days. It is a humanist approach, one that sees human
wellbeing for all as a priority and as a prerequisite for the wellbeing of
nature.
Environmental
scientist Jesse Ausubel suggests that humans decoupling from nature is our
goal. He suggests that the high values given to nature as “ecosystem services”
will in the future be valued less as we continue to decouple from nature.[3]
That depends on whether we are able to continue our efficiency increases well
beyond rebound effects. It is technology that enables us to decouple from
nature. He noted in a 1997 paper[4]
that: “Agriculture is by far the greatest transformer of the environment.
Cities, paved roads, and the rest of the built environment cover less than 5
percent of the land in the forty-eight contiguous American states. Crops occupy
about 20 percent of this land and pasture 25 percent. Crops cover 35 percent of
France and 10 percent of China. Agriculture has consumed forests, drained
wetlands, and voided habitats; the game is inherently to favor some plants and
animals over others. Farms also feed us.” I think Ausubel makes an
interesting point – that the value of ecosystem services and thus so-called
“natural capital” is not fixed but dependent on how coupled we are to nature.
According to Ian Bateman, professor at Exeter Business School and director of
the Land, Environment, Economics, and Policy Institute (LEEP), natural capital,
in the form of clean air, water, land, and energy is being incorporated more
and more and a natural capital approach is gaining traction internationally. We
should consider things like natural capital in the future economic value of
nature and keep that value viable as we are able but also be cognizant that it
is hard to put a value on it. Bateman came up with a decision-making framework
with three components: efficiency, assessing which option among
alternative options is most beneficial; sustainability, or how each
option affects stocks of natural capital; and equity, or who receives
the benefits of the proposed decision and when. The goal is to make decisions
that offer the most benefit to society while incorporating natural capital into
the cost-benefit analysis. An example he gives is reforesting an area that is
prime for agriculture. That would likely not be the best use of resources which
a good efficiency analysis would reveal.[5]
[1] Ruddiman, William F. (2005). Plows, Plagues, and
Petroleum: How Humans Took Over the Climate. Princeton University Press
[2]
Montgomery, David R., 2007, 2008, 2012) Dirt: The Erosion of Civilization.
University of California Press.
[3] Ausubel,
Jesse H., December 18, 2018. Ausubel: We Must Make Nature Worthless. Human
Progress. https://www.humanprogress.org/ausubel-we-must-make-nature-worthless/
[4]
Ausubel, J. H. (1997). The Liberation of the
Environment. In N. A. Engineering, & J. H. Ausubel (Ed.), Technological
Trajectories and the Human Environment (pp. 1-13). National Academy Press.
[5] Bateman, I. J. (2020, July 8). The natural capital
framework for sustainably efficient and equitable decision making. Nature
Sustainability, Abstract.
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