Remote Sensing Satellite Imagery Can Help Prevent Land Degradation
- Africa is an interesting case study in terms of preventing land degradation since there is much to learn from what other countries did in the development process, says LUCSUS researcher Genesis T. Yengoh.
He is doing research on how remote sensing imagery and methods of satellite data analysis can be used to assess and monitor land degradation in Tanzania, Kenya, Uganda and Senegal. The aim of the project – which is funded by the Global Environment Facility, GEF - is to contribute to the standardisation and harmonisation of datasets, methods, and tools for assessing land degradation, - which can aid decision makers in designing and implementing policies.
Through using remote sensing satellite imagery, Genesis Yengoh and his colleagues have been able to analyse vegetation trends in the four countries, and identify so called hot and cold spots of vegetation activity. Hot spots are areas where the vegetation is doing well, whereas cold spots are areas where the vegetation is declining. Of special interest to the project are areas where the decline cannot be attributed to yearly changes in rainfall or by the climate.
According to Genesis Yengoh these changes can have many different causes: for example biodiversity can change because of conversion of land from forest to land for crops, or land can degrade because of over cultivating from agriculture, or overgrasing from cattle.
- You begin by understanding the problem. Where is land degradation occurring, and why is it occurring? By having the data, methods and tools to monitor and assess the land degradation, you can start to attempt mitigation and prevention.
He says that this type of data, methods and tools are key for local and national decision makers in designing and implementing sustainable land conservation policies. It is a key step in achieving what is called “land degradation neutrality” where land degrading should at least be equal to the land improving. The data can help decision makers to find important answers to questions such as large agricultural yield gaps, which is a major problem in sub-Saharan Africa, and an important component in meeting food security on the continent.
- If you can see that land is degrading in an area where a specific crop is grown you can try different approaches to increase the yield such as modifying farming practices, adding nutrients or changing the cropping patterns. If land is degrading because of deforestation, the necessary deforestation abatement methods and practices may be considered.
While the use of remote sensing satellite imagery is not a new approach, Genesis Yengoh highlights that its use in Africa makes for a very interesting case study. This has to do with the fact that the development of this technology came later to Africa – which means that as a continent, Africa can build on the experience of other countries and parts of the world to leverage the use of this technology for its socio-economic development.
- It is very exciting in that we can support decision makers in developing a more sustainable approach to land maintenance based on new research and technological advances. We also have the opportunity and potential of avoiding mistakes such as in the fields of natural resources management made by other nations.
Another reason Africa is interesting is because of the food security component. According to Genesis Yengoh, the need to tackle and prevent land degradation is absolutely central in Africa since the population is growing very fast, which means that many African countries need support in feeding their populations.
- For me, this is a very important aspect of the project, and it links in with global efforts to meet the sustainable development goal about zero hunger. I really believe that our methods and tools can be of help to countries of the continent in getting the most food out of their land, while at the same time maintaining biodiversity and healthy vegetation.