Environmental damage has been one of the major challenges faced by the planet for three decades; but now, when the world is battling COVID-19 crisis, the need to expedite the restoration movement has been the most urgent. With the ecosystem loss, the world is getting increasingly deprived of carbon sinks, like forests and peatlands. And during a time like this, we can’t afford to let that happen. The process helps in facilitating the revival of degraded ecosystems to its pre-degraded trajectory; and conserving the ecosystems. Both biotic and abiotic aspects comprise the basis of ecological restoration. Resilience and regenerative ability of the ecosystem can be ensured through this holistic approach. Ecological restoration is the process of assisting the recovery of an ecosystem that has been degraded, damaged, or destroyed, as well as Conserving the ecosystem which are still intact. Now the natural ecosystem is focusing on the repairing of the damage which is caused by human.
The theme for World Environment Day 2021 is “Ecosystem Restoration” and will see the launch of the UN decades on ecosystem. Healthier ecosystems, with richer biodiversity, produce greater benefits, such as more fertile soils, higher yields of wood and fish, and greater reserves of greenhouse gases.
Humans change ecosystems in many ways, such as habitat destruction, pollution, introduction of invasive species, and overexploitation of species. The most common way that humans damage ecosystems is by destroying habitat. For example, we remove trees, change the flow of water, and change grasslands into farms. These practices can lead to local extinctions of species and cause other species to migrate to new areas. The structure of the world’s ecosystems changed more rapidly in the second half of the twentieth century than at any time in recorded human history and virtually all of Earth’s ecosystems have now been significantly transformed through human actions. The most significant change in the structure of ecosystems has been the transformation of approximately one quart (24%) of Earth’s terrestrial surface to cultivated systems. More, land was converted to cropland in the 30 years after 1950.
Approximately 35% of mangroves were lost in the last two decades. Roughly 20% of the world’s coral reefs were lost and an additional 20% degraded in the last several decades of the twentieth century. The most rapid changes in ecosystems are now taking place in developing countries, industrial countries historically experienced comparable rates of change.
The UN FAO estimate that 10 million hectares of forest were cut down each year. These are big numbers, and forest loss creates a number of negative impacts ranging from habitat loss which are responsible for the changing ecosystem.
We also pollute the air and water, leading to many effects on ecosystems. One major effect of air pollution is the accumulation of greenhouse gases in the atmosphere. These gases trap heat in Earth’s atmosphere, warming the planet and causing global climate change.
Figure no 1. Deforestation and plastic pollution are responsible for changing the pattern of ecosystem; Source: Interesting Engineering
Climate is an important environmental influence on ecosystems. Changing climate affects ecosystems in a variety of ways. For instance, warming may force species to migrate to higher latitudes or higher elevations where temperatures are more conducive to their survival. Similarly, as sea level rises, saltwater intrusion into a freshwater system may force some key species to relocate or die, thus removing predators or prey that are critical in the existing food chain.
Climate change not only affects ecosystems and species directly, it also interacts with other human stressors such as development. Although some stressors cause only minor impacts when acting alone, their cumulative impact may lead to dramatic ecological changes. For instance, climate change may exacerbate the stress that land development places on fragile coastal areas. Additionally, recently logged forested areas may become vulnerable to erosion if climate change leads to increases in heavy rain storms. Overexploitation reduces population sizes, affecting interactions within an ecosystem. Humans overexploit species by overhunting, overfishing, unsustainable logging, and unregulated pet trade. Even if a small element of an ecosystem breaks down, the whole system’s balance is threatened. Freshwater ecosystems are nowadays the most threatened ecosystems.
Introducing species into a new ecosystem can have serious consequences. For example, invasive clam species are dramatically changing the San Francisco Bay as they outcompete local populations and enjoy a population explosion without any predators.
Figure no 2. Deforestation and sea level rising are the result of changing natural ecosystems; Source: United Nations University
Why the ecosystem restoration is important for our environment?
When people choose to restore an ecosystem, the reasons can vary. Oftentimes intact ecosystems provide important natural services such as pollination, sequestering carbon from the atmosphere, filtering the groundwater or reducing erosion and desertification. By restoring ecosystems, scientists aim to replenish these services. For example, the mangrove forests of coastal wetlands, which provide important storm protection services. Half of them have been degraded. Mangrove is considered as important opportunity sites for restoration.
Another concern of many scientists is that our rate of biodiversity loss could eventually negatively impact our ability to grow food and access medicinal plants. Having a narrow range of genetic diversity on earth makes species more prone to disease and it puts them at greater risk of being unable to adapt to impacts like climate change. By restoring habitats, we can have a better chance of withstanding the environmental changes underway.
Ecological restoration is so important that recently, the United Nations Environmental Programme (UNEP) declared the decade from 2021 to 2030 the “UN decade on ecosystem restoration.” Huge potential value lies in the field. Currently 3.2 billion people suffer from negative impacts to the ecosystems. These impacts have been valued at an estimated loss of about 10 percent of the global annual GDP.
Ecosystem restoration at a global scale is important if we are to mitigate the extent of the ecological crisis that we are currently facing, and protect the biodiversity for future generations. Our food systems and the revival of forest and agrarian crops depend on healthy soils. But soil degradation not only compromises the essential value of the ecosystems but also its ability to produce healthy and sustainable foods. Therefore, the restoration of soil is important to sustain life on earth. In order to improve this situation, the Bonn challenge has been established to restore roughly 350 million hectares of degraded ecosystems this decade, we could remove 13-26 gigatons of greenhouse gases from the atmosphere.
Finally, people, animals and plants depend on healthy ecosystems. Our everyday lives and luxuries would not be possible without their services and resources. In A Sand County Almanac, author and ecologist Aldo Leopold states, “We abuse the land because we regard it as a commodity belonging to us. When we see land as a community to which we belong, we may begin to use it with love and respect.” Restoration gives us an opportunity to improve our relationship to the ecosystems we depend on, and allows us to become a constructive part of the communities that create our region’s natural environment.
Author is a Student of Environmental Science and Engineering, Jatiya Kabi Kazi Nazrul Islam University