38 percent of world’s surface in danger of desertification
“… the root causes of global environmental degradation are embedded in social and economic problems such as pervasive poverty, unsustainable production and consumption patterns, inequity in distribution of wealth, and the debt burden… success in combating environmental degradation is dependent on the full participation of all actors in society, an aware and educated population, respect for ethical and spiritual values and cultural diversity, and protection of indigenous knowledge”
Ministers of the Environment, Malmö, Sweden, May 2000
Life-Cycle Assessment (LCA) is a technique to assess the environmental aspects and potential impacts associated with a product, process, or service, by: compiling an inventory of relevant energy and material inputs and environmental releases; evaluating the potential environmental impacts associated with identified inputs and releases; interpreting the results to help you make a more informed decision.
A system or life cycle can begin with extracting raw materials from the ground and generating energy. Materials and energy are then part of manufacturing, transportation, use and eventually recycling, reuse, or disposal. A life cycle approach means we recognize how our choices influence what happens at each of these points so we can balance trade-offs and positively impact the economy, the environment, and society. A life cycle approach is a way of thinking which helps us recognize how our selections – such as buying electricity or a new t-shirt – are one part of a whole system of events.
Source: http://jp1.estis.net/sites/lcinit/default.asp?site=lcinit&page_id=138F5949-6997-4BE6-A553-585E92C22EE4#lcmwhy
Desertification: Desertification is the process which turns productive into non- productive desert as a result of poor land-management. Desertification occurs mainly in semi-arid areas (average annual rainfall less than 600 mm) bordering on deserts. Desertification does not refer to the expansion of existing deserts. It occurs because dryland ecosystems, which cover over one third of the world’s land area, are extremely vulnerable to over-exploitation and inappropriate land use. The primary reasons for desertification are overgrazing, over-cultivation, increased fire frequency, water impoundment, deforestation, overdrafting of groundwater, increased soil salinity, and global climate change. Over 250 million people are directly affected by desertification. In addition, some one thousand million (or one billion) people in over one hundred countries are at risk. These people include many of the world’s poorest, most marginalized, and politically weak citizens. Desertification is recognized as a major threat to biodiversity.
A number of methods have been tried in order to reduce the rate of desertification; techniques focus on two aspects: provisioning of water (e.g. by wells and energy intensive systems involving water pipes or over long distances) and fixating and hyper-fertilising soil. However, most measures treat symptoms of sand movement and do not address the root causes of land modification such as overgrazing, unsustainable farming and deforestation.
Sources: http://www.fao.org/desertification/intro_txt/en/desert.htm and http://desertification.wordpress.com
38 percent of world’s surface in danger of desertification
According to researchers from the Institute of Agro Food Research and Technology (IRTA), 38% of the land surface of the world is at risk of desertification. In their study the researchers included the impact of desertification in the LCA, based on classifying 15 natural areas or “eco-regions” according to their degree of aridity. By simultaneously using the LCA and a Geographic Information System (GIS), the researchers have shown that eight of these 15 areas can be classified as at risk of desertification.
The eight natural areas at risk of desertification are coastal areas, the Prairies, the Mediterranean region, the savannah, the temperate Steppes, the temperate deserts, tropical and subtropical Steppes, and the tropical and subtropical deserts. In these eight regions the greatest risk of desertification is in the subtropical desert regions – North Africa, the countries of the Middle East, Australia, South West China and the western edge of South America. These are followed by areas such as the Mediterranean and the tropical and subtropical Steppes. Coastal areas and the Prairies are at a lower risk of desertification.
Montserrat Núñez, lead author of the study says, “Unsustainable land use may lead to soil becoming degraded. If this happens in arid, semi-arid and dry sub-humid regions, such as Spain, this degradation is known as desertification, and the effects can be irreversible, because they lead to areas becoming totally unproductive.”
In order to establish their methodology, the researchers used four biophysical variables that are the main causes of desertification – aridity, erosion, over-exploitation of aquifers and risk of fire. The scientists explain, “This makes it possible to satisfactorily evaluate the impact of desertification of a particular human activity, and compare the impact of the same activity in a different place, or the impact of different activities carried out in the same place.”
This research also shows that using the LCA in combination with GIS makes it easier to adapt the LCA to study the impacts of land use, not only in the case of desertification, but also in terms of loss of biodiversity, erosion, or even water consumption. Referring to the need to combine LCA with GIS, Núñez explains, “Despite improvements in the LCA, it has a methodological weakness, which is a lack of environmental impact categories to measure the effect of human activities such as cultivation or grazing on the soil”.
Source: References: Núñez, Montserrat; Civit, Bárbara; Muñoz, Pere; Arena, Alejandro Pablo; Rieradevall, Joan; Anton, Assumpció. “Assessing potential desertification environmental impact in life cycle assessment” International Journal of Life Cycle Assessment 15(1): 67-78, enero de 2010.
February 10, 2010