Nature Based Solutions To Climate Change

 

Nature based solutions to climate change are exactly what they sound like. It is simply using nature to fight against climate change. This is done through both mitigation and adaptation, that is, in reducing greenhouse gas emissions and in protecting against the harshest impacts of climate change.

It includes using the naturally existing solutions to climate change, such as those used in the carbon cycle as carbon sinks. In this it envelops oceans, forests, grasslands, peatlands, wetlands, croplands and in general all marine and terrestrial ecosystems to combat the phenomenon.

Nature based solutions means the safeguarding (protection), restoration and sustainable management of these systems. According to the IPCC, we need to be carbon neutral by the half century mark, if at all we are going to keep warming this century below 1.5 degrees above preindustrial levels, which is one of the goals of the Paris Agreement. Carbon neutrality, otherwise known as net zero, is a term used to mean that the amount of carbon dioxide emissions entering the atmosphere equals the amount leaving the air and into carbon sinks. For this goal to be achievable however, the other greenhouse gases have to be cut in significant quantities.

A terrestrial-riverine ecosystem -iwaria

The IPCC estimates that planetary marine and terrestrial systems remove 56% of carbon dioxide emissions form the atmosphere.

Nature based solutions however don’t involve wind power generation or planting crops for bioenergy.

According to UNEP/IUCN, these methodologies on their own can sequester around 10 to 18 gigatonnes of carbon dioxide equivalent by 2050. Of this 62% would be from forested areas, 24% from croplands and grasslands like the prairies and savannahs, 10% from peatlands and 2% from oceans and related ecosystems.

Also known as ecosystem based adaptation (EbA), these approaches are a preferred way of fighting climate change because of many reasons. First, they are unlikely to have any major negative repercussion, because they already naturally existing and have been there for millennia. Additionally, these systems have other benefits, such as conserving and improving biodiversity (wildlife), they ensure food security and provide medicines as well. They regulate climate and buffer against natural disasters. They provide a livelihood to local and indigenous communities. They also attract tourism, and in these ways contribute to the economy. Natural systems are an important part of culture and have spiritual value, and are likewise used in recreation and relaxation.

It’s also been noted that the capacity of nature to sequester carbon on its own is being reduced in the southern half of the planet and augmenting in the northern half. This is because of land disturbances in the south and more regeneration in the North. Climate change also lowers vegetation acreage in the tropics.

Cutting emissions through nature based solutions (NbS) is the preferred mitigation method in developing countries, mainly because most of their emissions (over half) are land based.

Forests are the first major ecosystems that regulate climate. Forests like the two biggest: the Amazon of South America and the Congo forest of Central Africa are the lungs of the planet, and altogether remove carbon from the air to the tune of more than 2 billion tons. Forests however are under pressure from multiple stressors including agriculture, human encroachment, mining and the harvesting of trees for timber or fuel. The Amazon for example is under threat from logging, ranching (beef farming) and from mining as well. The Congo forest is also facing the same threat, albeit for the coal resources that are in the extensive underground peatland beneath the forest.

Forests are a good counter to climate change, because they absorb carbon dioxide from the atmosphere. Also, because of very high rates of evapotranspiration, they attract rainfall and shield against the sun, resulting in a microclimate that can extend for hundreds of kilometers depending on the size of the forest. They can induce cool temperatures that counter increasing high temperatures and also heat waves brought by climate change. Forests also are a source of rivers. That also protect the soil from erosion by both wind and water and ensure soil fertility from the decomposition of roots, leaves, trunks etc. This organic matter is further stored in the soil, adding to soil carbon stocks. Forests also house rare and endangered species like the mountain gorilla and provide medical benefits.

The Amazon however is slowly filling up its ability to capture carbon dioxide.

The UN recommends that each country should have at least 10% of its surface area under forests.

The way to approach forests when it comes to climate change is threefold. First is afforestation, which is the planting of completely new forests, reforestation is increasing the size of existing forests, while reafforestation is the replanting of cleared areas which were previously covered by forests. However, care should be taken in that the tree species used should be native and diverse, in order to avoid harm to wildlife and the soil. Restoring existing forests is better for climate because new forests will take time to grow, while mature trees store more carbon than seedlings. Deforestation and land degradation contributes to 13% of emissions globally.

Peatlands are areas of very rich carbon content, defined as waterlogged soils partially covered by water. So marshes, bogs, swamps, mires etc. Because of the acidic and anoxic (without oxygen) nature of such areas, all plant and animal debris remains undecomposed and so form rich carbon deposits. Peatlands cover only 3% of the earth’s surface but are constantly threatened by agriculture, settlement and mining, being drained for the aforementioned.

When peatland soils are disturbed for farming or any other activity, they actually emit more carbon than they sequester causing them to be a net source. To counter this, peatlands need to be protected by law, and also through education of the populace.

Croplands are the part of agriculture that sequesters carbon dioxide. Croplands are green plants, and all green plants absorb carbon dioxide in the presence of sunlight during photosynthesis to make carbohydrates.

So, in this way, they remove CO2 from the atmosphere and help the climate. But being used for food means that when they are cleared, all the carbon sequestered is released back into the atmosphere. Practices like mulching, cover crops, agroforestry, and conservation agriculture all mitigate climate change. The application of charcoal to soils (biochar) increases fertility and carbon storage. However, more help is needed in terms of subsidies toward climate smart agriculture, land tenure for farmers, workshops, trainings and extensions as well as financial and regulatory support.

Marine systems like mangroves, sea grass, and saltmarshes store carbon in sediments and in their trunks. They have a host of biodiversity benefits as well.  Mangroves for example store more than 360 tons of carbon dioxide per hectare. Seaweed like hyacinth which floats on water, also traps carbon because it is a green plant and when it dies it is stored in sediment. Seaweed farming is practiced and can be used in oceans to mitigate climate change.

Seaweed is also highly nutritious animal feed and would greatly cut livestock methane emissions. Seaweed also betters the quality of water and can be used to increase soil fertility. In other ways, decomposing bodies of sea animals form ocean carbon when they sink to the sea floor. So they enrich carbon in sediment.

Coastal systems face the threat of sea level rise and exploitation by human beings for various reasons. Large scale trawling and dredging disturb carbon quantities in sediment. Coral reefs also face the same threat.

Nature based solutions have two drawbacks in that one, they are reversible. The carbon stored can be re-released if these systems are mismanaged. Also, nature based solutions on their own can only alleviate the climate crisis by a third, and need to be combined with other industry solutions by cutting emissions in all economic sectors particularly energy, industry and transport.

To their credit though, they have wider support, both political and from the public because they are natural. They are also less expensive compared to other methods like carbon capture and storage.

For them to succeed however, they need to be socially inclusive, with gender and youth considerations factored in. They also need to align to the principles of sustainable development, that is, economically viable, socially equitable and environmentally safe.

Nature based solutions need not only a strong regulatory and policy framework, for protection; but also the involvement of indigenous and local peoples as well as the use and application of traditional knowledge systems coupled with research and technology transfer.

In addition to this, one has to create a sense of ownership to these ecosystems, by ensuring that the public is well educated and informed on the role of nature based solutions, climate change, the economy and the effect and benefits on their livelihoods and life in general.

Nature based solutions also need to be mainstreamed not only in the climate and environment plans of national and regional governments but need a bottom up approach. In fact, climate and environmental considerations need to be a part of the planning policy of each economic sector because climate change affects everything.

Financial assistance is a requirement to support natural solutions, because they need investments as well.

Lastly, they can be used as part of the carbon offset system, albeit with intentional and strict measures. One such initiative being the Reducing Emissions from Deforestation and Forest Degradation (REDD+) which is for the forestry sector.