Scientists Tell Conference How Everyone Can Help Revive Soil, Build Ecosystems
By The Earth & I Editorial Team
Two of humanity’s most pressing environmental crises—soil degradation and biodiversity loss—can be resolved with bold actions and by nurturing universal “environmental stewardship,” two eminent scholars told a conference held recently in a suburb of Washington, D.C.
The Earth’s environment is “everybody’s responsibility,” and there is no other choice but to work together, said Dr. Rattan Lal, a renowned soil scientist and 2020 World Food Prize Laureate, and Dr. Douglas Tallamy, a leading expert on species invasion and entomology at the University of Delaware.
The scholars gave their remarks at a June 15 conference in Gambrills, Maryland, with the theme, “Rejuvenating Our Ecosystems,” held in honor of UN World Environment Day (June 5) and sponsored by the Hyo Jeong International Foundation for Environmental Peace (HJIFEP), publisher of The Earth & I.* Partnering organizations for the event included the Universal Peace Federation (UK and USA), the Interfaith Partnership for the Chesapeake, University of Maryland Extension Anne Arundel County Master Gardeners, The Anne Arundel County Watershed Stewards Academy, and the Women’s Federation for World Peace (USA).
The Threat of Soil Degradation
“About 40% of global soils are degraded,” which impact “about 50% of the world’s population,” said Dr. Lal, founder and director of The Ohio State University’s Rattan Lal Center for Carbon Management and Sequestration. (See The Earth & I, August 2021.)
Soil is Earth’s “negative emissions entity,” and if humanity continues to take more from soil than it puts into it, environmental degradation will only worsen, he said.
Soil degradation results in biodiversity loss and reduced agronomic production, which affects economic prosperity and people's health. Soil degradation also reduces access to clean water, worsens drought, and, of course, aggravates food insecurity,” Dr. Lal added.
The professor reviewed the many ways soil can be degraded, such as “compaction; erosion; runoff; drought; and chemical degradation, which includes acidification, salinization, elemental imbalance, and nutrient mining.” Biological degradation includes “depletion of soil organic matter content and increase in pathogens.” There are also types of land misuse like excessive tillage, overgrazing, residue removal or burning, excessive water use, and war and political instability.
The Biodiversity Crisis
In addition to soil degradation, there are also global challenges with biodiversity, especially insect loss, said conference co-presenter Dr. Tallamy, author of Bringing Nature Home: How You Can Sustain Wildlife with Native Plants.
“We're going to have to save functioning ecosystems on at least half of the planet, or they will disappear everywhere.”
“We're going to have to save functioning ecosystems on at least half of the planet, or they will disappear everywhere,” Dr. Tallamy said, referencing Edward O. Wilson’s book, Half-Earth: Our Planet's Fight for Life, which calls for half the planet to be dedicated to nature.
Functional ecosystems are “built from a series of very specialized interactions, largely between animals and plants,” said Dr. Tallamy. But today, many of these ecosystems are in trouble as the result of what is called “human-dominated landscapes” or places where nature “hangs on by a thread.”
Human development has even led to an “insect apocalypse,” or massive loss of insects due to human activities to remove the weeds that insects and pollinators need to thrive. “It turns out pollen specialization is very common in our native bees,” Dr. Tallamy explained. “We've got between 3,600 and 4,000 species of native bees, and over a third of them can only reproduce on the pollen of particular plants.”
Moreover, insect loss is deadly to bird populations, since they feed their young with insects, Dr. Tallamy said. The US and Canada alone have lost a total of “3 billion breeding birds in the last 50 years” or one third of the North American bird population.
Bold Solutions
One bold solution is to become serious about building public and private landscapes that embrace the whole picture in ecosystems—including the needs of insects, plants, and birds—with each part contributing toward the life of the whole, Dr. Tallamy said.
“We need a new approach to conservation here in the US," Dr. Tallamy said. “We have to go beyond conservation into restoration. We have to rebuild the nature that we have destroyed.”
“It's going to take an army of private citizens to do it, but we have an army of private citizens to do it,” he added.
“I think the solution is to start to practice conservation outside of parks and preserves—on [privately held] landscapes.”
“Where should we start?” Dr. Tallamy asked the audience. Since large swaths of land are in private hands, “I think the solution is to start to practice conservation outside of parks and preserves—on [privately held] landscapes,” he said.
“Seventy-eight percent of the lower 48 states is privately owned, and 85.6% of the land east of the Mississippi is privately owned. If we don't practice conservation on private property, we're going to fail, and failure is not an option.”
To those who think what they do on their property is no one else’s business, Tallamy responded, “What happens in our yards does not stay in our yards. And this is where people who think they have the right to do whatever they want on their property are wrong. Does my neighbor have the right to kill [or] destroy my watershed? Does my neighbor have the right to destroy the pollinator communities that I need for the plants on my property? To destroy my food web? [Or] to not sequester carbon?”
He added that having incentives may be more effective than penalties for changing people’s minds: “If we change the tax incentives, you actually get a tax break for having less lawn or having keystone plants, [for example]; that changes minds ... quickly.”
Plant Choice Matters
The “building blocks” of these new ecosystems must be their most important contributors, Dr. Tallamy cautioned, noting that not all species contribute equally. Flowering plants are essential as are the pollinators that allow those plants to reproduce.
Laying out his plan, Dr. Tallamy said: “So now we have the food that animals need tied up in [these] plant tissues,” mostly in leaves where photosynthesis takes place. Animals are needed to disperse seeds, pollinate, and provide pest control. But to complete the picture, plants that attract the right insects must be present because most invertebrates don’t eat plants—they eat other invertebrates that eat the plants.
Caterpillars Are Key
Dr. Tallamy knows the right insects for the job. “Caterpillars turn out to be enormously important in transferring energy from plants to animals. Caterpillars are transferring more energy from plants to other organisms than any other type of plant eater,” he said.
Citing his own experience feeding seed to Carolina chickadees in his backyard, Dr. Tallamy said only about 50% of their diet is seeds, even in winter, with the other 50% being insects and spiders. And, he noted, “when [the birds] reproduce, their babies can't eat seeds at all.”
In a healthy environment, Dr. Tallamy said, “96% of our terrestrial birds rear their young on insects, and most of those insects are caterpillars.”
So, how many caterpillars does it take to raise a nest of chickadees? “It takes 6,000 to 9,000 caterpillars to get one clutch of chickadees to the point where they leave the nest.”
Responding to a question from the audience, “What is the best way to count and identify the number of caterpillar species on my oak tree?” Tallamy said, “You have to look at the right time of year. Looking at night with a flashlight is the best way [since] the caterpillars are hiding during the day [and] the birds are very good at finding them.”
He added that the birds have “eaten just about everything that’s out there” during their reproduction phase, so that the end of July, early August [Mid-Atlantic region, USA] is “a very good time to look for caterpillars.”
But there is a drawback. Most plants do not support many caterpillars. “So, we have to be fussy about which plants we’re landscaping with,” said Dr. Tallamy. He cautions that one can try to landscape to attract monarch butterflies, for instance, “but they only like one of the milkweeds.”
“We are not going to rebuild functional ecosystems if you don't have functional food webs within those ecosystems, and that's not going to happen if we don't choose the right plants.”
“We are not going to rebuild functional ecosystems if you don't have functional food webs within those ecosystems, and that's not going to happen if we don't choose the right plants,” he emphasized.
Balancing Give and Take in Nature
Circling back to solutions for soil degradation, Dr. Lal unveiled a simple principle that guides his work with soil: “Soil organic matter is the heart of soil health.” This is why it is so important, he repeated, to not take more from soil than is put into it. Otherwise, the soil becomes degraded, and the only carbon negative entity (soil) and industry (farming) on the planet is thrown out of balance. And far worse, he said, “you are degrading all forms of life.”
Dr. Lal said this thinking comes from the “One Health” concept, rooted in Vedic literature, which recognizes the five elements of “soil, water, air, energy, and space” that constitute the human body. This is why “the health of soil, plants, animals, people, the environment, and the planet is one and indivisible.”
Dr. Lal emphasized the need for policy innovations, such as establishing a Soil Health Act (SHA) to protect the sustainable management of soil. Why, he asked, is there a Clean Air Act and a Clean Water Act but no such act for soil?
“We must also promote education on soil and the environment and the law of return that I mentioned,” he advised. “The law of return states that any substance we take from nature must be returned to the place from which it was taken.”
Self-Sustaining Solutions
Also vital to Dr. Lal’s plan is rewarding farmers for ecosystem services. “The word is not subsidy. You're not providing a handout, a donation, no! You are providing farmers with additional income to promote essential ecosystem services. That's a big difference,” he explained.
Humanity must focus on the re-carbonization of the terrestrial biosphere, he urged. Why re-carbonization? “We lost carbon from [wild] vegetation and soil when we converted to agriculture,” he said. “We must put it back.” This, he said, is the “bedrock” of sustainable development for which there are many practices.
“We have a moral duty to increase economic productivity from existing land, restore degraded land, and convert some agricultural land back to nature,” Dr. Lal added. By 2100, Dr. Lal’s goal is to return half of all crop land, which is 750 million hectares (1.85 billion acres) back to nature, as well as 3,700 million hectares (9.14 billion acres) of all grazing land.
Why do we keep on emphasizing greater food production when there is so much food waste? The world produces enough food to feed 10 billion people.”
“Why do we keep on emphasizing greater food production when there is so much food waste?” he asked the audience. “The world produces enough food to feed 10 billion people.” Food and nutritional security must be achieved, he said, but not necessarily by producing more commodities. A promising avenue is to cut back food waste, which is conservatively estimated to be 30%, including in the US.
“Food,” Dr. Lal said, “should be considered as God's gift.” He added, “To a hungry man, God can appear only in the form of a loaf of bread, and that made from grains grown from a healthy soil. And therefore, wastage of that gift from God, which is essential to maintaining the good health of everybody concerned, is not acceptable.”
Dr. Lal also pleaded to stop using food as a weapon. “We increase access to food by addressing poverty, inequality, and war, especially war,” he said. Therefore, governments and organizations should improve food distribution and increase consumption of pulses [lentils, chickpeas, beans, and the like] and plant-based dishes while moderating consumption of meat.
Both scholars pointed to the necessity of people around the world collaborating to resolve these challenges.
Restoring the environment is “everyone’s responsibility,” said Dr. Tallamy. “Therefore, we must all work together,” Dr. Lal said. “Each of us is a victim and a culprit, so we all have a moral responsibility” to protect the environment.
*HJIFEP, publisher of The Earth & I, is a non-profit environmental service organization that sponsors environmental science conferences, including the ICUS and ICSG conference series. HJIFEP conferences feature presentations from eminent scientists on pressing global environmental issues and solutions.
HJIFEP’s mission is to build a world of peace in which all people live in harmony with the Creator, with one another, and with the natural environment. HJIFEP serves under the motto, “Loving Nature, Healing the Earth.”
Attendees of the "Rejuvenating Our Ecosystems" conference joined the event in-person and virtually from over 10 nations, including the UK, South Korea, Japan, The Netherlands, and Australia and included concerned citizens and environmental scientists alike, as attendance was open to all. The conference featured a vigorous global Q&A session with each of the scientists.