Laura J. Martin is an environmental historian at Harvard University. She wrote two articles (1,2) about the origins of ecological field studies that might help explain the destructive methods still used today by some ecologists. Professor Martin “contends that the history of ecosystem science cannot be separated from the history of nuclear colonialism and environmental devastation in the Pacific [Nuclear Testing] Grounds” (2)
When the US dropped two atomic bombs on Japan in 1945, little thought was given to the consequences of atomic bombs because ending the war in the Pacific was the only consideration. Japan surrendered to the US less than one month after the bombs were dropped, effectively ending World War II.
Few doubt that the use of atomic weapons was instrumental in ending World War II. After the war, there was a more sober effort to determine the consequences of using atomic weapons. Some believed that nuclear weapons might replace conventional warfare. Others wanted to understand the impact on life on the planet before making such a momentous decision. This effort was focused on practical considerations such as the impact on the world’s fisheries and food supply. The objective of their initial studies was less concerned about long-term consequences for the environment such as the duration of impacts on living creatures and the environment in which they live.
The US federal government invested heavily in the sciences after World War II. The Atomic Energy Commission (AEC) was established in 1946 and the National Science Foundation (NSF) in 1950. The availability of federal grant funding for academic institutions “dramatically reconfigured the relationships among federal, academic, and corporate spheres.” (2) Increased federal funding greatly increased the number of academic research projects.
Between 1945 and 1970, the US detonated 105 nuclear weapons. The Atomic Energy Commission and later the National Science Foundation paid academic ecologists to conduct field studies at the test sites to determine the impact on animals.
In 1963 the US, Soviet Union, and Great Britain signed a Partial Test Ban Treaty that prohibited all non-wartime detonations except for those done below ground. Testing of the effects of radiation by academic scientists continued because the AEC mass produced radioisotopes and distributed them to American institutions. Scientists were no longer constrained to field sites where atomic bombs had been detonated.
The availability of radioisotopes made laboratory testing possible, but it also enabled large-scale atomic irradiation experiments such as a forest irradiation project in Georgia that exposed 300 acres of forest to an air-shielded reaction (?) that produced radiation levels comparable to expected fallout following a nuclear catastrophe. The purpose of that experiment was to determine the impact of radiation on forests. The findings were that some tree species were more vulnerable to radiation than others. This finding contributed to the hypothesis “that the greater number of species in an ecosystem, the better that system will be ‘adjusting to stress.’” (1) This is the familiar theory that greater biodiversity enhances resiliency of ecosystems against stressors such as climate change. It remains a cornerstone of conservation science.
These studies are also responsible for the knowledge that radiation—and many other toxic substances such as chemicals—bioaccumulate, first described publicly in 1955, according to Martin. Many toxic substances persist in our bodies throughout our lifetime. The longer we are exposed to them, the more dangerous they are to our health. Women who were exposed to DDT before it was banned in 1972 still have higher levels of DDT in their bodies than women born after 1972. Many toxic chemicals also bioaccumulate in food webs. Top predators in the food web are more heavily burdened with poison than animals at the bottom of the food web because of biomagnification.
Using pesticides to study impacts and recovery
The concept of destroying an ecosystem for the purpose of studying impacts and recovery from impacts was soon extended to using pesticides. In a study funded by NSF in the 1960, herbicides were repeatedly applied to clear-cut plots in the White Mountain National Forest to compare the runoff from “disturbed” watershed with “undisturbed” control watersheds. “They concluded that forest clear-cutting led to the leaching of nutrients from the soil, and ultimately, algal blooms in downstream waters.” (1) (Yet, 60 years later, spraying clear-cuts with herbicides is still the norm in the timber industry.)
Destructive methods used by Daniel Simberloff
The first publication (3) in 1969 of Daniel Simberloff’s academic career was a report of his Ph.D. dissertation project under the direction of EO Wilson at Harvard University. He tented and fumigated with methyl bromide 6 mangrove islands off the Eastern shore of Florida to kill all the insects. His objective was to study how long it would take for insects to recolonize the islands.
Although Simberloff monitored the islands for only one year, he concluded, “The colonization curves plus static observations on untreated islands indicate strongly that a dynamic equilibrium number of species exists for any island.” (3) This is an example of the generalized conclusions of ecological studies noted by Professor Martin: “With ecosystem studies, ecologists claimed that fieldwork conducted in one place could be used to understand other distant and different places. The Pacific Proving Grounds became a model for lakes in Wisconsin, rain forests in Panama, deserts in China…” (2)
Some 60 years and thousands of ecological studies later, such generalizations are rarely considered credible. To quote one of the academic scientists who advises me, “If you study a specific site, you know something about THAT site at THAT specific point in time.” Nature is too dynamic to reach a sustainable equilibrium and its complexity cannot be accurately generalized. The concept of a sustainable equilibrium ecosystem was rejected by scientists long ago.
Laura Martin says of Simberloff’s study, “Destruction thus became a method of studying ecosystems. As Eugene Odum put it: ‘ecologists need not feel bashful about attacking ecosystems so long as they observe the rules of good science.’” (1)
Methyl bromide used by Simberloff in his thesis project is known to deplete the ozone layer of the atmosphere that shields the Earth from harmful Ultraviolet light that causes skin cancer. Its use was severely restricted by an international treaty in 1989. However, it is still used in the US for agricultural crops as a soil sterilant that kills all living organisms in the soil.
The federally mandated Material Safety Data Sheet for methyl bromide says it is acutely toxic to aquatic life at the highest danger rating (Category 1).
Nearly 60 years after the publication of his Ph.D. study, Daniel Simberloff remains one of the most vocal advocates for the eradication of non-native plants and animals. With few exceptions, those eradications require the use of pesticides. Simberloff may not have known the damage that methyl bromide does in the environment at the time of his study, but surely he knows or should know now. Yet, he is still committed to the eradication of non-native plants, projects that require the use of pesticides.
Many ecological studies and associated “restoration” projects adopt the same viewpoint that destruction is a justifiable method of studying and “restoring” ecosystems. “Restoration” projects often begin by killing all non-native plants with herbicides before attempting to create a native landscape. Rodenticides and insecticides are used to kill non-native animals with the understanding that many native animals will inevitably and unintentionally be killed. The Endangered Species Act accommodates the by-kills of these projects by issuing permits for “incidental takes.” The law and the scientific community make a distinction between killing individual animals and killing animals on a scale that threatens the survival of the species.
Killing and destruction were established as legitimate scientific tools over 70 years ago. Given what we know now about pesticides and radiation and at a time when habitats are being destroyed by human activities and climate change, is it time to question the legitimacy of habitat destruction as a scientific tool?
A Preview
Professor Martin is also the author of her recently published book, Wild by Design: The Rise of Ecological Restoration. I look forward to reading it. Meanwhile, I hope Professor Martin’s papers about the destructive origins of ecological field studies are a preview of her book.
Happy New Year! We hope 2023 will be a more peaceful year.
(Sources: Conservation Sense and Nonsense)
Đăng nhận xét