Hydrology and the looming water crisis: It is time to think, and act, outside the box

In a number of respects, it is exciting to be a hydrologist these days. Very innovative work has been published lately, and it deservedly generates a lot of enthusiasm and intellectual excitement. In this journal alone, several very interesting articles (Budagovskyi and Novak, 2011a,b; Doležal et al., 2012; Kovář et al., 2012; Machlica et al., 2012; Pavelková et al., 2012) have recently contributed in a significant manner to increase our understanding of key aspects of mainstream hydrology and water resources. A number of areas have seen particularly interesting advances. Some of the most stimulating developments in recent years have been in the significant broadening of spatial scales at which we can now investigate the fate and transport of water in the environment, and in the opening up of hydrology to other disciplines, like biology and ecology, which has allowed water-related processes to be studied from novel vantage points. Thanks to amazing technological advances during the last decade, especially in terms of X-ray computed tomography, it is now possible to obtain detailed, micron-scale information about the geometry of the spaces through which water and the solutes it carries percolate in natural porous media. There are still some practical issues to work out with this technology, like the thresholding of 3D images of soils to produce binary blackand-white images (e.g., Baveye et al., 2010; Houston et al., 2013; Schlueter et al., 2010), but nevertheless the fundamental information CT scans can afford has already led to new insight concerning, e.g., the influence of soil architecture on processes occurring in soils (Baveye et al., 2011). These microscopic data have spurred interest in non-traditional approaches to the modeling of water and solute transport, using for example the Lattice-Boltzmann approach (e.g., Baveye et al., 2010; Falconer et al., 2012; Vogel et al., 2005), which is definitely a step forward compared to classical approaches to pore-scale modeling, involving artificial networks of cylindrical capillaries (e.g., Thullner and Baveye, 2008). At the other extreme of the scale spectrum, advances in satellite sensing technology and software are allowing hydrologists to monitor broad features of the water cycle, like the depletion of groundwater storage in various parts of the world (e.g., Anderson et al., 2012), or the spatial distribution of water-related ecosystems like wetlands and marshes (e.g., Laba et al., 2008). The combination of hydrology with biology and in particular ecology, has been one of the key developments of the last two decades. Starting with Slichter (1905), hydrologists have been keenly aware for over a century of possible connections between microorganisms and the hydraulic and transport properties of soils and aquifers, and Slichter's (1905) observations have been followed by many others (Allison, 1947; Darnault et al., 2003; DeLeo and Baveye, 1997; DeLozada et al., 1994; Gupta and Swartzendruber, 1962; Jacobson et al., 2005; Qureshi et al., 2003). Nevertheless, these research efforts were very focalized on specific issues, like the bioclogging of soils or the transport of pathogens and contaminants, and did not attempt to envisage all the possible ways in which biology and ecology have bearing on water resources. This more systematic perspective has been explored by increasing numbers of researchers over the last 20 or so years, yielding valuable insight about numerous processes (e.g., Lichner et al., 2012). One particularly positive feature of this trend has been the fact that, even though some researchers are talking about "biohydrology" and "ecohydrology" as if their intent were to create new disciplines (with all that this implies of launching new journals, creating dedicated scholarly societies, holding separate meetings), researchers by and large have resisted the urge to do so. The terms "biohydrology" and "ecohydrology" appear to serve occasionally as rallying calls for focused conferences and special issues of journals, but otherwise researchers who work in these areas are still very much integrated in the whole hydrology community, which from my perspective is a very good thing (Baveye, 2011). So, there are many reasons to feel upbeat about the way hydrology and research on water resources are evolving. However, there are also several reasons to be concerned about the future. One of these reasons has to do with the tremendous increase we are currently experiencing not only in the number of published articles in the field, but also in the number of new journals cropping up continuously, supposedly to satisfy the exploding publishing demand. Elsevier, for example, recently announced the launching of no less than four new Water Resources journals. The sad thing about this publishing frenzy is that one the key reasons so many articles are published, and new journals are being created unnecessarily when traditional journals should suffice, is that administrators of universities and research centers, particularly in the US but now also in other countries, persist in using meaningless metrics, like the yearly number of published articles, to gage faculty productivity (e.g., Baveye, 2010; Siegel and Baveye, 2010; Trimble et al., 2010). The paper glut, which results from this lack of vision and could be easily alleviated, is nothing to be excited about, unfortunately. It is not at all clear who besides the publishers themselves will profit from all the new journals being launched, who will be reviewing the masses of manuscripts that are produced, or, perhaps most importantly, who will have time to read the tens of thousands of articles that eventually get published. In this last respect, particularly, it is not obvious at all who will be able to carry out the integrative, interdisciplinary research that is needed to deal with increasingly complex water-related issues, once researchers will have been forced to specialize into extremely narrow subdisciplines to be able to keep up with an