Discussing responses to climate change impacts often centers on mitigation or adaptation, yet as we’ve seen with integrated landscape management, the two are not mutually exclusive and often there are additional co-benefits from these actions. Today, Brenda Lin, whose work focuses on how natural systems or components of natural systems can be maintained or integrated into an increasingly developed landscape to provide ecosystem services, offers an example of how mitigation efforts can result in other benefits. However, hers is a cautionary tale, stressing that policy and incentives often dictate the trajectory of land management decisions. As such, policy decisions play a critical role in moving beyond carbon-centric focus and considering the wider range of benefits that an integrated agricultural landscape can provide.
The Australian landscape, often spoken of as the sun-burnt country, is iconic of the kangaroo, red desert, and dry, cracking soils. Although this is a continent that experiences hot, dry climates, there is actually a substantial mix of agriculture found across the country, with huge markets in wheat, cattle, cotton, and other commodities sold for both domestic and international consumption. Such products have proven to be lucrative endeavours for landholders, but with greater pressure on food prices and increasing costs of production, farmers are challenged to look for new ways to maintain economically viable farm businesses.
This is where the introduction of a carbon market comes in. One way of adding value to current farm businesses is the option for landholders to sell carbon credits to the international market. This has been presented as an additional way for farmers to make money with what is grown directly on their farms. Farmers would continue to grow crops, but there is a great potential to change production styles or land management in ways that allow for more trees to be planted across the landscape to sequester carbon. Although this sounds straightforward, there are numerous ways in which one could add trees across these farm landscapes, and each method has potential extra benefits (or disadvantages) for environmental and human well-being.
There are many creative ways to add trees to farmlands that both sequester carbon and help restore biodiversity and ecosystem services. Agroforestry allows for a multi-species collection of trees and shrubs to be integrated into the farm crop system. Revegetation of marginal crop land can lead to permanent tree plantings in areas that are no longer useful for growing crops. Plantings that try to take advantage of native species can help rebuild natural community structures that return some of the lost ecosystem services to the landscape. Many of these services will actually also be beneficial for farmers, such as increased pest control and pollination, and protection of crops through windbreaks. Other services will benefit everyone in the landscape, such as reduced soil erosion, increased water filtration, and improved air quality.
The easiest way to plant trees on a farm, however, is in monocultures of single species, and this is often done in rows with trees of all the same age. Although this is the cheapest way to add trees to the landscape as there are fewer labor costs, it is probably obvious to see why such plantings do not necessarily improve the biodiversity of the region or provide many of the ecosystem services that benefit the farmer and the local community. However, many landholders who want to take advantage of the potential extra profit from carbon sequestration will naturally move toward this option.
Thus, the challenge is how to incentivize landholders to plant trees on their farms in a way that increases biodiversity and ecosystem services when the easiest way to gain carbon credits through plantings leads to few environmental benefits. Such questions are key when implementing any policy that encourages tree plantings for carbon sequestration, since certain methods have much greater benefits to environmental and human well-being than others. But what information will be necessary to help convince landholders to choose the options that increase biodiversity and ecosystem structure? Are the ecological benefits for the farmer enough or does there need to be an additional economic gain provided?
These are the questions that will continue to drive research into tree plantings for carbon sequestration, especially if we want to see farmers choose environmentally friendly revegetation strategies over simple monocultures. Considering the potential financial consequences that may come with the developing carbon market, these decisions will become ever more relevant.
Lin, B.B. et al. 2013. Maximizing the Environmental Benefits of Carbon Farming through Ecosystem Services Delivery. Bioscience 63: 793-803.