The sustainable management of water and other precious natural resources is one of the defining challenges of our time and a main concern for farmers and public authorities alike. The demand of those resources grows simultaneously with the population, so it would become scarcer over time. Fortunately, we now have a solution for water conservation, which is especially good news for those farms located in drought-stricken areas, such as Spain. Smart water management technologies using data derived from sensors to monitor fields in real-time can help to mitigate the severity of droughts in the future.
2017 was the third driest year on record, behind 1981 and 2005. At 43 % capacity, reservoirs were at their lowest levels in decades according to the Spanish Ministry of Agriculture, Food and Environment. They are normally at around 60 % at this time of the year. Other parts of Southern Europe were also impacted with dramatic crop losses up to 70 %. “Use of water in agriculture is a key problem for the 21st century: without improvements neither the consequences of climate change will be manageable nor [will] the demand of 2 or 3 billion additional people for food be met”, stated Prof. Wolfgang Lucht of the Potsdam Institute for Climate Impact Research (PIK) in Germany. Therefore, the main challenge to confront water management in agriculture is to improve water use efficiency and its sustainability. How to achieve that is literally a million-euro question.
Generally, this can be done through tracking and quantifying water fluxes at different spatial and temporal levels. Monitoring the plant rooting zone - where water sources from rainfall, irrigation, plant transpiration, and drainage losses from crop-growing areas intersect – remained a challenge until innovative technologies using the Internet of Things (IoT) recently entered the playing field. Smart sensors using isotopic and nuclear techniques can tell farmers which part of their fields actually need water at any given time. The sensors transmit data to a cloud platform, allowing farmers to better manage their type of crops, the growth stages, and the overall agro-ecosystem to minimize not only resource use but also nutrient losses. By closely monitoring the arable land, sprinklers automatically turn on and water the plants at the exact time when more irrigation is needed and shut off when the perfect moisture level is reached.
However, further substantial improvements in agriculture would be needed to meet the food demands of the world's growing population. Through mulching and different tillage systems, water evaporation from the soil could be cut by 50%, while turning the fruitless evaporation into productive plant transpiration. According to researchers, such measures alone could increase global crop yield up to 25%. In addition, a study suggests that rainwater should be harvested in ponds or with the help of dikes and subsurface dams to compensate for dry periods. In this way, global crop yields have the potential to be augmented by up to 31% while saving one of our most precious resources.