Tvedt argues that food production systems must be analysed by locating them within particular water systems. Given that ecology is a very broad concept including numerous understandings and many aspects of ‘nature’ and thus difficult to study empirically and in a rigid comparative manner, he rather suggests a more specific term for studying such systems in a comparative perspective: agro-water variability. This directs attention to the role of different types of water regimes in different food production regimes, and by using it as a sort of methodological entry-point, the greater agro-ecological variability might be easier to reconstruct and analyse.
Irrigation and canals among the Hunza people, Himalaya, Pakistan
China’s water and food security has global political and economic consequences
The scarcity of water as a ticking time bomb, the Dead Sea, Israel
Canals and agriculture in one of the hottest and most arid places on earth – the Oman desert
Luxor, once the Pharaohs’ capital of Egypt, and the Nile
The Nubia civilization along the banks of the Nile, North Sudan
The wells of wealth among the Borana, Ethiopia
Water and the world’s most famous animal migration in the wild life sanctuary Serengeti, Kenya
One of the volumes of the A History of Water Series (Series III, vol. III) deals with agro-water variability and the development of food production in Africa, showing that this variability is not a gradient, with fading amounts of precipitation from the rainforests to the deserts – from 5,000 mm to 0 mm. If this had been the case, the predictability and adaptability would have been rather straightforward. If it is one thing that characterizes statistical averages concerning precipitation, it is that the actual rainfall in a given year is hardly ever the average: more often than not it is extreme one way or another. In other words, there is hardly ever a ‘normal’ year; the erratic and unpredictable rainfall patterns become ‘the norm’. Moreover, the total inter-annual amount of precipitation is not always the most relevant measure. If there are two rainy seasons – the long and the short – what matters fundamentally for agriculturalists is that the right amount of water comes at the right time. In particular, rain-fed agriculture is highly vulnerable to erratic precipitation patterns. If the rains fail, or are abundant at the wrong time for the cultivation season, it may have devastating consequences. Moreover, too intensive rains may destroy crops, which also need sun; and the perfect balance between heavy and light rain for some days, then sun and more good rain, and so on, are parameters that nobody can predict but which farmers are dependent upon for a successful harvest. Importantly, the actual rainfall may also be very specifically localized, even within small areas. As a consequence, not only are what and when to grow fundamentally affected, but also where within a village, creating systems of multi-plot approaches aimed at predicting and reducing risk. Understanding the social consequences of this great agro-water variability in time and space is crucial when comparing most African food regimes with, for instance, development and the Green revolution in Asia.