Editorial: toward 50 years of 'Water Resources Research'

The first issue of 'Water Resources Research' (WRR) was published in March 1965 and, therefore, the year 2015 will present the exciting opportunity to celebrate the 50th anniversary of the journal. Naturally, this milestone will be seen as an occasion to look back on 50 years of research activity. The history of WRR provides a very interesting perspective on the development of hydrology and the legacy of the worldwide water resources community

Reducing Food Loss and Waste to Enhance Food Security and Environmental Sustainability

While food shortage remains a big concern in many regions around the world, almost one-third of the total food production is discarded as food loss and waste (FLW). This is associated with about one-quarter of land, water, and fertilizer used for crop production, even though resources and environmental constraints are expected to limit food production around the world. FLW reduction represents a potential opportunity to enhance both food security and environmental sustainability and therefore has received considerable attention recently. By reviewing the recent progress and new developments in the literature, this paper highlights the importance of FLW prevention as a complementary solution to address the Grand Challenge of global food security and environmental sustainability. However, raising awareness only is not enough to realize the expected FLW reduction. We identify the knowledge gaps and opportunities for research by synthesizing the strategies of FLW reduction and the barriers, including (1) filling the data gaps, (2) quantifying the socioeconomic and environmental impacts of FLW reduction strategies, (3) understanding the scale effects, and (4) exploring the impacts of global transitions. It is urgent to take more aggressive yet scientifically based actions to reduce FLW, which require everyone’s involvement along the food supply chain, including policy makers, food producers and suppliers, and food consumers

The Interplay Between Bioenergy Grass Production and Water Resources in the United States of America

We apply a land surface model to evaluate the interplay between potential bioenergy grass (Miscanthus, Cave-in-Rock, and Alamo) production, water quantity, and nitrogen leaching (NL) in the Central and Eastern U.S. Water use intensity tends to be lower where grass yields are modeled to be high, for example in the Midwest for Miscanthus and Cave-in-Rock and the upper southeastern U.S. for Alamo. However, most of these regions are already occupied by crops and forests and substitution of these biome types for ethanol production implies trade-offs. In general, growing Miscanthus consumes more water, Alamo consumes less water, and Cave-in-Rock consumes approximately the same amount of water as existing vegetation. Bioenergy grasses can maintain high productivity over time, even in water limited regions, because their roots can grow deeper and extract the water from the deep, moist soil layers. However, this may not hold where there are frequent and intense drought events, particularly in regions with shallow soil depths. One advantage of bioenergy grasses is that they mitigate nitrogen leaching relative to row crops and herbaceous plants when grown without applying N fertilizer; and bioenergy grasses, especially Miscanthus, generally require less N fertilizer application than row crops and herbaceous plants

Managing Multiple Mandates: A System of Systems Model to Analyze Strategies for Producing Cellulosic Ethanol and Reducing Riverine Nitrate Loads in the Upper Mississippi River Basin

Implementing public policies often involves navigating an array of choices that have economic and environmental consequences that are difficult to quantify due to the complexity of multiple system interactions. Implementing the mandate for cellulosic biofuel production in the Renewable Fuel Standard (RFS) and reducing hypoxia in the northern Gulf of Mexico by reducing riverine nitrate-N loads represent two such cases that overlap in the Mississippi River Basin. To quantify the consequences of these interactions, a system of systems (SoS) model was developed that incorporates interdependencies among the various subsystems, including biofuel refineries, transportation, agriculture, water resources and crop/ethanol markets. The model allows examination of the impact of imposing riverine nitrate-N load limits on the biofuel production system as a whole, including land use change and infrastructure needs. The synergies of crop choice (first versus second generation biofuel crops), infrastructure development, and environmental impacts (streamflow and nitrate-N load) were analyzed to determine the complementarities and trade-offs between environmental protection and biofuel development objectives. For example, the results show that meeting the cellulosic biofuel target in the RFS using Miscanthus x giganteus reduces system profits by 8% and reduces nitrate-N loads by 12% compared to the scenario without a mandate. However, greater water consumption by Miscanthus is likely to reduce streamflow with potentially adverse environmental consequences that need to be considered in future decision making

Downgrading Recent Estimates of Land Available for Biofuel Production

Recent estimates of additional land available for bioenergy production range from 320 to 1411 million ha. These estimates were generated from four scenarios regarding the types of land suitable for bioenergy production using coarse-resolution inputs of soil productivity, slope, climate, and land cover. In this paper, these maps of land availability were assessed using high-resolution satellite imagery. Samples from these maps were selected and crowdsourcing of Google Earth images was used to determine the type of land cover and the degree of human impact. Based on this sample, a set of rules was formulated to downward adjust the original estimates for each of the four scenarios that were previously used to generate the maps of land availability for bioenergy production. The adjusted land availability estimates range from 56 to 1035 million ha depending upon the scenario and the ruleset used when the sample is corrected for bias. Large forest areas not intended for biofuel production purposes were present in all scenarios. However, these numbers should not be considered as definitive estimates but should be used to highlight the uncertainty in attempting to quantify land availability for biofuel production when using coarse-resolution inputs with implications for further policy development