The definiton of marginal land can be explained from an economic point of view as well as from an agricultural perspective. However, it does not matter which definition of marginal land you come across, one phrase is surely there: low in value. Is this really the case? Are marginal lands entirely useless for human purposes and making profit? This article below begs to differ. Cultivating bioenergy crops such as Arundo donax turns a marginal land with a low value to a highly profiting investment – the marginal land not only produces valuable bioenergy sources, but it improves over time to be able to produce food crops.
What is marginal land?
A land might be called marginal for a several reasons. It may have poor water supply or poor soil quality. These areas are defined as „econimcally marginalised land”, whereby food crop cultivation could be attempted, but the low yield would not cover the costs of harvesting. In some cases an area might be polluted from earlier industrial activities, making it useless and even risky for cultivating food. These sites are marked by erosion, salinization and/or low organic carbon contents.
Geographical features (such as excessive slope, or excessive distance from means of transportation) also contribute to a land being labelled as marginal. Deserts, flood plains and tidal basins are also considered to be marginal lands.
Marginal lands can be found across the world in pretty much all countries. According to a recent study, in China alone the total area of marginal lands which could be used for growing bioenergy crops is about 43.75 million hectares. Moreover, it is often argued that around 10% of the land utilised for agriculture, is in fact, marginal – but it is still uneffectively exploited.
Listen to the definition of marginal land here!
The importance of marginal lands
Despite the common beliefs, marginal lands are not without importance. If we wanted to name a commonplace usage of marginal lands, we would mention grazing grounds. Some breeds of free-roaming livestock, like the English Leicester sheep, are able to forage on these lands.
Resilient, perennial bioenergy crops, such as Arundo donax or Miscanthus, are also notable candidates, which can be cultivated and profited from even on conteminated, flooded or dry sites. In a world, where an estimated 21,000 people die every hour from hunger we certainly cannot afford using fertile and healthy soil for producing bioenergy, instead of growing food crops and feeding those in need. And vice versa! We can not afford the luxury of producing biofuels from edible crops.
However, there is another reason why the world should realize the importance of marginal lands and make a use of it: the crisis of marginal landholders. A research in India concluded that there is a significant positive relationship between the percentage of marginal, indebted farmers and suicide rates, making suicide the second leading cause of death in the country.
Bioenergy crops on marginal lands – but which one?
The most advantageous and profitable use of marginal lands would be the cultivation of bioenergy crops, thus producing green energy.
Among the many energy crops, Arundo donax (also known as giant reed grass) is an outstanding one. It is well known for its wide scope of adaptability to a broad range of environments, and an amazing yield of 50-80 dry tonnes per hectare per year. Arundo donax is able to survive and tolerate wide ranges of pH and salinity:
a pH in the range of 5.0 to 8.7
One can only profit from planting Arundo donax, since this energy crop has numerous options of usage. Bioethanol, biogas, pellets, paper and even furniture are produced from this giant reed, just to mention a few.
However, in the case of conteminated marginal lands, one feature of Arundo donax should be highlighted the most: phytoremediation. This natural procedure uses living plants to cleanse polluted soil, and the high metabolism rate of Arundo donax makes it possible tobreak down contamination faster than most plants.
As a byproduct the use of the giant reed grass also reduces soil erosion. An increase was reported several times in both organic matters and microbal biomass content in lands where Arundo was planted.4
Land that was once marginal can become productive again, bringing remedy for world hunger, livelihood crisis and even climate change.