The views expressed by columnists do not necessarily reflect those of the Bay Journal.

The Earth is about 4.5 billion years old, or 4.5 eons. Of that time, humans have only been around for about 200,000 years, with civilization only beginning about 6,000 years ago and industrialization, a little more than 200 years ago.

It’s difficult to put this into perspective, especially when one considers the damage that humans have wrought on the world’s ecosystems. We live in “the now,” seeking instant gratification. As a society, we give precious little thought to the products we produce and the fate of those substances in our environment. We demand “fast food” and expect an immediate response to our email, texts and tweets.

The beauty of nature is in its adaptability and resilience. Nature constantly seeks a balance. But it does so over thousands or tens of thousands of years. In the relatively short amount of time we humans have been on this Earth, we have upset that balance in many ways, some of which have yet to be recognized or acknowledged. Canadian scientist and academic David Suzuki, author of The Sacred Balance, comments, “If we humans are good at anything, it’s thinking we’ve got a terrific idea and [then] going for it without acknowledging the potential consequences or our own ignorance.”

Witness the manufacture and use of DDT, (dichloro-diphenyl-trichloroethane) which was developed as the first of the modern synthetic insecticides in the 1940s. It was initially used with great effectiveness to combat malaria, typhus and other insect-borne human diseases among both military and civilian populations. It also was effective for insect control in crop and livestock production, institutions, homes and gardens. DDT’s quick success as a pesticide and its broad use in the United States and other countries caused many insect pest species to develop a resistance to it. But it also had a significant impact on wildlife populations, specifically eagles and osprey, which were nearly driven to extinction.

The U.S. Department of Agriculture, the federal agency with responsibility for regulating pesticides before the formation of the U.S. Environmental Protection Agency in 1970, began regulatory actions in the late 1950s and 1960s to prohibit many of DDT’s uses because of mounting evidence of the pesticide’s declining benefits and environmental and toxicological effects. The publication in 1962 of Rachel Carson’s Silent Spring stimulated widespread public concern over the dangers of improper pesticide use and the need for better pesticide controls.

It wasn’t until 1972 that the EPA issued a cancellation order for DDT based on its adverse environmental effects, such as those to wildlife, as well as its potential human health risks. Since then, research has continued, and based upon animal studies, a relationship between DDT exposure and reproductive effects in humans is suspected. In studies, some animals exposed to DDT developed liver tumors. As a result, DDT is now classified as a probable human carcinogen by U.S. and international authorities.

DDT, known to be very persistent in the environment, accumulates in fatty tissues of animals — including humans — and can travel long distances in the upper atmosphere.

After the use of DDT was discontinued in the United States, its concentration in the environment and animals has decreased, but because of its persistence, residues of concern from historical use still remain. Eagles and osprey populations have rebounded because of protections established under the Endangered Species Act. But it took nearly 35 years from the time that DDT was banned for that recovery to take place.

So what have we learned from the DDT experience? Today, we have a number of emerging contaminants such as pharmaceutical byproducts, endocrine disruptors and micro-plastics. As long as society is content with addressing these issues after the crisis occurs, the restoration effort must continue and adapt. The effort in the Chesapeake Bay watershed is a model for restoration initiatives around the world. But even we have a lot to learn.

What we don’t know about the environment and how ecosystems function is astounding. We have mastered electronic communications and the internet, but we know relatively little about how ecosystems function and the relationships among species. It is further complicated because the indicators used to determine the health of the Bay watershed and the progress being made are subject to the vagaries of weather and natural fluctuations.

Cold winters, for example, can have an impact on the mortality of juvenile blue crabs, and subsequently the adult female blue crab stock. We may also see improvements in water quality, water clarity, dissolved oxygen and Bay grasses after prolonged periods of drought because there is less runoff of nutrients and thus less algal production. Relying on short-term data can be misleading, so it is essential to focus on long-term trends.

In the 2015 Chesapeake Bay Report Card, the University of Maryland Center for Environmental Sciences found that Bay health improved without a long-term drought and that “[T]he overall Bay Health score (53 percent) in 2015 was one of the highest recorded.” We are now observing improvements in Bay health during times of near-normal streamflows.

In addition to being a great natural resource that provides us with clean air, clean water and healthy soil, the Chesapeake Bay watershed is a significant economic resource. The watershed’s regional economy provides 8.3 million jobs and generates an annual income of nearly $400 billion. According to the USDA, the watershed’s farming industry consists of 83,000 farms with annual agricultural production of $10 billion. Commercial fishing and seafood industries directly generate more than 5,000 jobs and an annual income of $56 million; while recreation and tourism produce more than 820,000 jobs and $13 billion in income. Even lands managed by the National Park Service within the Chesapeake Bay watershed produce 27,000 jobs and $2.3 billion in annual economic benefits.

While an ecosystem takes time to respond to human activities – both negative and positive – it functions over a long span of time. Our economy and the political system, though, can change quickly and dramatically. Products can be developed, manufactured, consumed and disposed of very quickly before we understand the unintended consequences. These systems are out of sync with the ecosystem. How do we reconcile the two?

Over the last three and a half decades, the Chesapeake Bay Program partnership has made substantial investments at the federal, state and local levels in restoring and protecting this economic asset. These investments have paid significant dividends. It is critical that we figure out how to reconcile this important ecosystem with our economic and political system so it will continue to give us a return on our investment.