Climate change and variability will impact water availability and the food security of India. Trend analyses of historical data indicate an increase in temperature and changes in rainfall pattern in different parts of the country. The general circulation models (GCMs) also project increased warming and changes in precipitation patterns over India. This chapter presents examples of model applications in water management and crop yield simulation in India, focusing on climate change impact assessment. Simulation models have been successfully applied for rotational water allocation, deficit irrigation scheduling, etc. in different canal commands. Application of a universal soil loss equation in a distributed parametric modeling approach by partitioning watershed into erosion response units suggests that by treating only 14% of the watershed area, a 47% reduction in soil loss can be achieved. Simulation studies conducted using different hydrological models with different climate change projections and downscaling approaches showed varied hydrological responses of different river basins to the future climate change scenarios, depending on the hydrological model, climate change scenarios, and downscaling approaches used. Crop yield modeling showed decreases in irrigated and rainfed rice (Oryza sativa L.) yields under the future climate change scenarios, but the decrease is marginal for rainfed rice. Maize (Zea mays L.) yields in monsoon may be adversely affected by a rise in atmospheric temperature, but increased rain can partly offset those losses. Wheat (Triticum aestivum L.) yields are likely to be reduced by 6 to 23% and 15 to 25% during the 2050s and 2080s, respectively. A combined bottom-up participatory process and top-down integrated modeling tool could provide valuable information for locally relevant climate change adaptation planning.

In winter 2004/2005, 1532 Water Pipits were recorded during 37 censuses carried out along an established route on a sewage farm flooded with wastewater (Wrocław, SW Poland). Single birds were seen in nearly 39% of all 299 encounters, while the largest concentrations, between 16–28 individuals, accounted for 9%. 78% of all birds were observed on meadows flooded with communal wastewater. The remaining ones stayed around irrigation ditches (n = 172, 11.5%), sedimentation basins (n = 88, 5.9%) and reedbeds (n = 72, 4.8%). The mean size of the Water Pipit concentration was largest on the meadows (mean ± SE = 6.54 ± 0.50 individuals) and smallest at the sedimentation basins (mean = 1.44 ± 0.14). In this winter season (December-first half of March), rainfall enlarged numbers of birds to forage on the meadows, and the thickness of the snow cover was positively correlated with bird abundance at the sedimentation basins. The dominant available prey items inhabiting the warm wastewater were Diptera larvae (96%), 88% of which belonged to the genus Eristalis. The mean (± SD) invertebrate biomass was highest in the basin sediments (1.03 ± 1.14 g/dm³ of deposits), and lowest on the flooded meadows (0.20 ± 0.37 g/dm³ of deposits). The results point to the significance of the artificial environmental conditions created by warm sewage water, which enable the birds to remain largely independent of the weather and thus to overwinter in a cold region of central Europe.

Water contamination by pathogenic bacteria is a global public health problem. Contamination of surface water utilized to irrigate food products, or for human consumption, causes outbreaks of foodborne and waterborne disease. Of these, those caused by diarrheagenic Escherichia coli (DEC) strains present substantial morbidity and mortality. The aim of this study was, therefore, to investigate the microbiological quality of surface water and the presence of DEC strains in different water bodies. A total of 472 water samples were collected from irrigation canal, dam, river, and dike water bodies from January through December 2015 in Sinaloa, a State located in Northwestern Mexico. Our studies demonstrated that 47.0% (222/472) of samples contained thermotolerant coliforms above permissive levels whereas E. coli strains were isolated from 43.6% (206/472). Among these E. coli isolates, DEC strains were identified in 14% (29/206) of samples including in irrigation canal (26/29) and river water (3/29) collected from the northern (83%) and central area (17%). Isolated DEC strains were classified as enteroaggregative E. coli (EAEC) 34.4% (10/29), enteropathogenic E. coli (EPEC) 31.0% (9/29), diffuse adherent E. coli (DAEC) 27.5% (8/29), and enterotoxigenic E. coli (ETEC) 6.8% (2/29). Moreover, 90% of isolated DEC strains exhibited resistance to at least one commonly prescribed antibiotic in Mexico whereas 17% were multi-drug resistant. In conclusion, the presence of DEC strains in surface water represents a potential source for human infection, and thus routine monitoring of DEC in surface water and other indirect affected areas should be considered at northwestern Mexico.