Water and Environmental Change

Environmental change does not always influence water in the way we would imagine especially as there is often more than one contributing factor.  Climatic changes in the Sahel region of Africa have lead to hydrological changes. Since the end of the 1960s extremely low rainfall, especially in comparison the previous decades, lead to long lasting droughts   (Leblanc et al, 2007) . Despite the decrease in rainfall an increase in ground water resources and river discharge has been observed particularly in southwest Niger, this is known as the Sahelian paradox   ( Favreau et al, 2009 ) . Since it is not rainfall that is responsible for the hydrological change observed, research suggests that land use change provides an explanation   (Leblanc et al, 2007) .  The Sahel region which is semi-arid has experienced one of the world’s largest population growth since 1950, the combination of high population and low yielding land has lead to a widespread increase of cropland  ( Favreau et al, 2009 )

In my previous post I looked at how land use change is connected to a changing climate, biodiversity and water. I tried to give a general sense of what happens as thresholds are crossed and the impacts of land use change. However it is important to realise that there is no one formula and depending on the circumstances differing impacts can be experienced. That is why our preconceptions about land use change are not always accurate and that interactions are complex.  A great example of this is shown in the work of Leach and Fairhead (2000) who used examples from West Africa to assess the relationship between population increase and deforestation.  They argued that neo-Malthusian ideas lead us to assume that as population increase results in a loss of forest due to the expansion human activities. Whereas neo-boserupian ideas assume that an advancement of technology and methods to provide for populations without straining resources will come about.  Instead  Leach and Fairhead (2000)   

I have discussed climate change as a form of environmental change throughout my blog.  Now, I want take a closer look at land use change and its connection to water in Africa..  First, i t is important to note that different forms of environmental change  are often connected and affect each other.  For example, t here are a number of methods by which climate and land use change interact to cause changes in biodiversity ( Oliver and Morecroft, 2014 ). This can be seen in  West Africa where increased droughts and the expansion of farmland has impacted the habitat and biodiversity in the  W-Arly-Pendjari  area ( ZSL, n/a ).  In addition, increased droughts may require irrigation for agriculture may alter water availability for other organisms  ( Oliver and Morecroft, 2014 ) .  Land cover change can impact the hydrological cycle and water resources in a number of ways as it changes the way the rain is separated through the vegetation and soil, this can effect surface run off, groundwater

Water is key to survival. I have discussed precipitation patterns and the effects of changing rainfall patterns on people and a lthough incredibly important, the animals we own and the crops we grow are not the only flora and fauna that rely on precipitation. That is why I thought I would look at how the wider ecosystem is affected by water variability, using an example of a natural migration towards water.   The reliance on water by animals is displayed through the migration of species that respond to seasonal precipitation variability and travel extremely long distances through the year. An example of this seen in the Serengeti, located in Tanzania and Kenya, where the great migration involving up to 1.4 million wildebeest occurs  (Holdo and Fryxell, 2009 ) . The animals move from the South which is characterised by short grassland in the wet-season to the north and west characterised by tall grass woodland and savanna in the dry-season  (Holdo and Fryxell, 2009) .  Wolanski et al, (

I recently watched a documentary which I heard about through a colleagues blog , called 'Brave Blue World: Racing to Solve Our Water Crisis', which sparked my interest so I thought I would share it.  The film focuses on innovation towards sustainable water and uses examples from all over the world, making it clear that difficulties regarding water resources are not just found in developing regions. Often the water crisis is discussed in a negative light and rightly so, however this documentary gives people hope that we are moving in the right direction, that there is potential to deal with the issues. The correct management is crucial and it starts at a local scale. They split the water crisis down into three key areas - water scarcity, the need for resilient infrastructure with regards to climate change and making it affordable. I thought this was a good way to take all factors into consideration, from the physical aspects of water availability and the interdisciplinary impact