{'fraction_non_alphanumeric': 0.013444767441860465, 'fraction_numerical': 0.001816860465116279, 'mean_word_length': 5.432242990654205, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Ensuring food security via improvement in crop water productivity

In many parts of the world, water scarcity is increasing, and many people see reducing the amount of water for agriculture as one way to make more water available for cities and industries, and also for the environment. This drives the demand to produce enough food for future generations with the same or less water than is presently available to agriculture, i.e., there is a need to increase water productivity (ratio of mass or value of product to volume or value of water depleted or diverted) without compromising food security. This paper seeks to contribute to the debate whether this is possible and to identify research needs to increase crop water productivity, such that food security can be ensured and farmers' livelihoods enhanced without increasing water diverted for agriculture over that in 2000. Available information indicates that crop water productivity varies a good deal from one spatial scale to another. Adequate data and information are lacking for a complete assessment of crop water productivity, especially at scales larger than the field level and in economic terms. Quantifying crop water productivity reveals gaps in knowledge regarding the best ways to increase crop water productivity. Most of these gaps relate to our inability to fully quantify all flow components in the domain of interest, their interactions with the plants, agricultural inputs and the environment in the process of producing marketable yields. Interactions among the hierarchical scales add to the complexity of the problems. Recent breakthroughs in molecular breeding and advances in modeling, information and communication technologies will accelerate our understanding of interrelated factors that influence crop water productivity and identification of interventions that will lead to improved crop productivity at various scale levels. The paper suggests that these interventions should not be pursued in isolation but that a systems approach is required, which integrates improved resources management (of both land and water) and agronomic practices with varietal improvement through conventional plant breeding and molecular biology. This approach should also take into account the interactions among the hierarchical scales and between the socioeconomic and the biophysical components of the agro-ecosystems to understand farmers' views of water-productivity-enhancing technologies. 3 The paper proposes a number of priority topics for research on crop water management in the Challenge Program on Water and Food, which will be amended during the development of the Program. These studies are grouped into four categories of research issues: effective development of …