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Highlights • Predicted green roof water retention performance varies widely across Canada. • Vegetation type had a greater influence than increases in substrate storage. • High water use plants best in locations with infrequent moisture limited conditions. • Runoff harvesting would provide for adequate irrigation between rainfall events. • Hourly ET rates predicted by Hargreaves and PM models differ slightly. Abstract In recent decades, urbanization has led to more frequent flood events in urban areas. Several studies have shown the promise of green roof technology for storm water reduction. However, limited studies have assessed water retention performance of green roofs in a range of climates. To investigate the retention performance of a green roof in various Canadian climates, several cities across the country (Vancouver, Calgary, Regina, Toronto, London, and Halifax) were selected. The water balance equation along with evapotranspiration (ET) models were employed to simulate runoff produced by green roofs in these six Canadian cities for two different vegetation types. A seven year simulation period was selected running from 2000 to 2006, with modeling conducted for eight months of the year using hourly time steps. The results showed that the performance of a green roof in runoff reduction depends on location, varying from 17% to 50% for low water use plants. The best performance in storm water reduction was predicted to occur in Regina and Calgary, while the poorest performance was predicted for Halifax and Vancouver. However, the average annual water retention (mm) was the highest in Toronto and London and the lowest in Vancouver, with Calgary, Regina and Halifax showing intermediate performance. Sensitivity analyses were performed for substrate depth, porosity, and wilting point to determine the importance of each for green roof performance for the different cities. The results revealed that the vegetation type had a greater impact on the water retention performance of green roofs than increases in substrate storage capacity associated with different substrate depth, porosity and wilting point over the range assumed in this study. [ABSTRACT FROM AUTHOR]

Negative effects of land use change on water resources are among the most important environmental problems widely found in rapidly developing urban areas. Preserving green open spaces, including peri-urban agriculture, has been emphasized in urban planning to maintain or enhance the water catchment capacity of a landscape. However, the effect of agriculture on water-related landscape functions varies depending on the type, distribution, and management of farmland. This paper analyzes the dynamics of agricultural land and its effect on runoff and soil erosion, in order to support agricultural land management in Jabodetabek Metropolitan Area (JMA) with Indonesia’s capital Jakarta at its core. In 2012, agricultural land in JMA covered 53% of the total area, mostly located in the peri-urban zone. Peak Flow and Universal Soil Loss Equation (USLE) models were used to quantify the increase of runoff and soil erosion in the three most important water catchment areas in JMA caused by an expansion of dryland agriculture and mixed gardens from 1983 to 2012. Critical zones, which generate most of the runoff and soil erosion, were identified in each of the catchment areas. While reforestation of farmland in these zones will be only an option on steep slopes given the great food demands and rural livelihood, adoption of soil and water conservation practices can make a substantial contribution to reduce flood risks and conserve the productivity of agricultural land. A specific set of policy incentives is recommended considering agricultural land use types distribution and their impact on runoff and soil erosion. [ABSTRACT FROM AUTHOR]

Stormwater constructed wetlands are not well characterised for their ability to remove pathogens which can pose public health risks during stormwater harvesting activities. This study investigated the behaviour of faecal indicator organism Escherichia coli ( E. coli ) and reference pathogen Campylobacter spp. in stormwater constructed wetlands, using a case study system located in Melbourne, Australia. Grab sampling and event-based monitoring revealed influent concentrations of E. coli were typical of other urban stormwater studies, yet Campylobacter concentrations were orders of magnitude above those urban stormwater studies used to develop the Australian Guidelines for Water Recycling, reached levels typical of raw domestic wastewater. The wetland consistently removed E. coli from stormwater (mean log removal 0.96, range 0.19–1.79), while Campylobacter spp. concentrations were often higher in outflow than inflow (mean log removal 0.05, range −0.9-1.25). These results indicate that E. coli is a poor indicator for this reference pathogen. The log reductions of both organisms also failed to meet the criteria specified for any end-use, as listed in the Australian Guidelines for Water Recycling, suggesting further treatment is required prior to harvesting. Finally, this study proposed that direct faecal deposition by waterfowl faeces was a microbial source to stormwater wetlands and that this was partly responsible for the varied microbial removal rates observed. Overall, this work validates the need for further characterisation of pathogens in raw urban stormwater, and the ability for water sensitive urban design features, such as wetlands, to remove both indicator and pathogenic microorganisms. [ABSTRACT FROM AUTHOR]

The environmental impact of irrigated agriculture on water quality was assessed in Landazuria watershed (Navarre, northeast Spain), a 479.5 ha watershed with 53% of irrigated agricultural land. In the framework of a long-term monitoring program, precipitation and discharge were measured at 10-min intervals and compound daily water samples were collected during the agricultural years (September to August) 2007–2016, and analysed for nitrate (NO 3 − ), phosphate (PO 4 3− ), sediment and total dissolved solids (TDS) concentrations. Typical agricultural management (including crop surfaces, irrigation and fertilization rates) was obtained from inquiries to farmers. Concentration and yield of the studied variables presented a high degree of variation, both intra- and inter-annual. Median concentration for the entire study period were 185, <0.05, 31 and 2284 mg L −1 for NO 3 − , PO 4 3− , sediment and TDS, respectively. NO 3 − -N and PO 4 3− -P yields averaged 74 and 0.04 kg ha −1 year −1 , respectively. NO 3 − -N yield was higher than in other agricultural land uses in Navarre and in the order of magnitude of other irrigated areas in the Middle Ebro Valley. PO 4 3− -P yield was in the same order of magnitude than in rainfed watersheds in Navarre but lower than in intensively grazed watersheds. Sediment yield was extremely variable, averaging 360 kg ha −1 year −1 , with 44% of the total measured load recorded in a few days. It was in the lower range of those measured in Navarre for rainfed agriculture and similar to those estimated in other irrigated areas of the Middle Ebro River. TDS concentration presented a significant decreasing trend since available salts were being washed out, while TDS yield averaged 1.8 Mg ha −1 year −1 . Long-term monitoring of irrigated areas is required to understand pollution processes in these agroecosystems and to adequately characterize the environmental impact of current agricultural practices on water quality, in order to implement, and adequately assess, measures to reduce agricultural pollution. [ABSTRACT FROM AUTHOR]

Roof runoff is an important source of urban stormwater and a main source of rainwater harvesting. Deposition of pollutants on rooftops can have a negative impact on runoff quality and, therefore, on harvested rainwater. Laboratory experiments with simulated rainfall were performed in order to study the washout of fine sand particles deposited on a ceramic tile roof, by runoff, considering the effect of the particle position, particle areal load, particle connectivity and roof slope. Results indicated that particle washout was influenced by the particle position on the roof; particle transport peak and transported mass was higher for the particle mass positions closer to the outlet. Increase in particle areal load decreased particle transport whereas particle connectivity had no effect on particle transport. However, roof slope was a dominant aspect in the particle washout; increase in roof slope greatly increased particle transport peak and transported mass. It also remarkably increased the first flush effect. [ABSTRACT FROM AUTHOR]

Stormwater harvesting (SWH) is an important water-sensitive urban design (WSUD) approach that provides an alternate water supply source and improves runoff quality through integrated systems of stormwater best management practice (BMP) technologies. In SWH system design, practitioners must account for trade-offs between cost, supply volume, and water quality improvement performance, which depend on design decisions for the type, size, and spatial distribution of BMPs. As such, the design of SWH systems with distributed BMPs is a complex, multiobjective optimization problem with a large decision space. This paper presents a multiobjective optimization framework to assess trade-offs in spatially distributed SWH system designs. The framework was applied to a case study for a housing development in Adelaide, South Australia. The results illustrated the potential benefits of distributing BMPs in an integrated SWH system where space at the catchment outlet is limited. Trade-offs between volumetric reliability and total suspended solids (TSS) reduction indicate that large gains in TSS reduction can be achieved with limited reduction in volumetric reliability. Concept designs in low-cost/moderately reliable and low-cost/high TSS reduction trade-off regions contained biofilters in locations receiving large inflows. [ABSTRACT FROM AUTHOR]

Unfortunately, in Lebanon and other countries in the Middle East region, water becomes scarcer than ever before, and over the last decades the demand on domestic water has increased due to population and economic growth. Although rainwater harvesting is considered to be a safe and reliable alternative source for domestic water, the inconvenience or impracticalities related to the cost and space needed for the construction of ground or underground storage tanks makes this practice not widely common in rural areas and rarely implemented in urban cities. This paper introduces a new technique to rainwater harvesting which can be easily used in both rural and urban areas: it collects and stores rainwater directly in tanks already installed on building roofs and not necessarily in special ground or underground ones. If widely adopted in Lebanon, this technique could help in: (1) collecting around 23 MCM (70 % of the current deficit in the domestic water supply) of rainwater and thus increasing the available water per m of building by 0.4 m per year, (2) saving around 7 % of the amount of electric energy usually needed to pump water from an aquifer well and ground or underground tank, and (3) considerably reducing the rate of surface runoff of rainwater at the coastal zones where rainwater is not captured at all and goes directly to the sea. [ABSTRACT FROM AUTHOR]

Feeding cattle on cropland through the winter months using pre-placed fodder bales (bale grazing or in-field bale feeding) has demonstrated economic benefits when compared to confined winter feeding, but very little research has been done to quantify the impacts of recurring cycles of in-field feeding on runoff water quality. In this study, two small watersheds (with and without winter bale grazing; WBG) located in the same annual cropped field in southern Manitoba, Canada were monitored from 2008 to 2016. Winter feeding in the WBG treatment occurred in the winters of 2008/09, 2010/11, 2012/13, and 2014/15. Export of N and P with the WBG treatment was also contrasted with the alternative practice of higher density confined feeding (CF). For WBG, soil fertility was improved, with higher soil test phosphorus (Olsen-P) and soil nitrate (NO 3 − -N) following WBG. Exports of N and P with surface runoff were also higher in snowmelt following WBG when compared to the control watershed, primarily due to higher concentrations of particulate N and P, NH 4 + -N, and dissolved organic N. Higher P loss from the WBG watershed than from the control watershed persisted in the non-grazing years following each bale grazing. In contrast, concentrations of all forms of nitrogen in runoff consistently returned to levels observed prior to bale grazing following a winter without treatment. Annual runoff export of N and P per animal unit day (AUD) following WBG was comparable to that for two CF sites. Higher annual volumes of runoff were observed from the larger area and lower density bale feeding treatment, but with lower concentrations of N and P in comparison to feedlot sites. If WBG continues to be utilized to improve soil fertility and reduce manure transportation costs, the potential negative impacts on runoff water quality must be considered. Higher volumes of snowmelt runoff per AUD from WBG in comparison to CF sites will make runoff capture options more expensive to implement. WBG timing or siting changes that reduce runoff volume and make retention feasible or that decrease accumulation of P at the soil surface will reduce negative water quality impacts associated with WBG. [ABSTRACT FROM AUTHOR]

In semi-arid to arid environments, water is the most constraining resource for agricultural communities. In Southeast Arabia (Sultanate of Oman and United Arab Emirates), the demographic growth and the increase of sites at the beginning of the Iron Age II (1100–600b.c.) is generally attributed to the development of groundwater harvesting techniques, and more precisely toqanāttechnology. While only little is known on the origin of this technology, even less is known about other hydraulic techniques, which could have been used as a complementary source of water. An irrigation system, recently discovered near an Iron Age settlement in the oasis of Masāfī (UAE) was studied thanks to the combination of various methods—archaeology, geoarchaeology/micromorphology, spatial analysis, and chronology—which have allowed us to identify the technological development of small-scale runoff farming and to link this practice to social as well as environmental issues. [ABSTRACT FROM AUTHOR]

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Especially in the Himalayan headwaters of the main rivers in South Asia, shifts in runoff are expected as a result of a rapidly changing climate. In recent years, our insight into these shifts and their impact on water availability has increased. However, a similar detailed understanding of the seasonal pattern in water demand is surprisingly absent. This hampers a proper assessment of water stress and ways to cope and adapt. In this study, the seasonal pattern of irrigation-water demand resulting from the typical practice of multiple cropping in South Asia was accounted for by introducing double cropping with monsoon-dependent planting dates in a hydrology and vegetation model. Crop yields were calibrated to the latest state-level statistics of India, Pakistan, Bangladesh and Nepal. The improvements in seasonal land use and cropping periods lead to lower estimates of irrigation-water demand compared to previous model-based studies, despite the net irrigated area being higher. Crop irrigation-water demand differs sharply between seasons and regions; in Pakistan, winter (rabi) and monsoon summer (kharif) irrigation demands are almost equal, whereas in Bangladesh the rabi demand is ~100 times higher. Moreover, the relative importance of irrigation supply versus rain decreases sharply from west to east. Given the size and importance of South Asia improved regional estimates of food production and its irrigation-water demand will also affect global estimates. In models used for global water resources and food-security assessments, processes like multiple cropping and monsoon-dependent planting dates should not be ignored. [ABSTRACT FROM AUTHOR]

The coastal region of Bangladesh has been identified as the most climate induced, hazard-prone, hard-to-reach area in Bangladesh. The conventional drinking water sources (rivers, ponds, groundwater) in the coastal area have become contaminated recently due to saltwater intrusion from the rising sea levels and frequent natural disaster. Household rainwater harvesting could be an alternative measure for reducing impact of climate change on water supplies because of the availability of rainwater. This study is to explore the potential of household rainwater harvesting for drinking purposes in the coastal area of Bangladesh. Rainwater harvesting is found technically feasible on the basis of rainfall pattern, household roof constructing material, and roof size. The annual rainfall of over 1900mm with inter annual variability of 0.18, makes the rainwater harvesting ideal in the coastal areas. Harvested rainwater can satisfy household monthly drinking water demand from March to October. The excess rainwater stored in September and October is sufficient to meet the demand in the dry months (November to February) provided there is adequate storage facility. The quality of stored rainwater was satisfactory from chemical parameters perspective and additional treatment is recommended for the harvested rainwater due to frequent detection of microbial contamination. [ABSTRACT FROM AUTHOR]

This study adopts rainwater harvesting systems (RWHS) into a stormwater runoff management model (SWMM) for the spatial design of capacities and quantities of rain barrel for urban flood mitigation. A simulation-optimization model is proposed for effectively identifying the optimal design. First of all, we particularly classified the characteristic zonal subregions for spatial design by using fuzzy C-means clustering with the investigated data of urban roof, land use and drainage system. In the simulation method, a series of regular spatial arrangements specification are designed by using statistical quartiles analysis for rooftop area and rainfall frequency analysis; accordingly, the corresponding reduced flooding circumstances can be simulated by SWMM. Moreover, the most effective solution for the simulation method is identified from the calculated net benefit, which is equivalent to the subtraction of the facility cost from the decreased inundation loss. It serves as the initially identified solution for the optimization model. In the optimization method, backpropagation neural network (BPNN) are first applied for developing a water level simulation model of urban drainage systems to substitute for SWMM to conform to newly considered interdisciplinary multi-objective optimization model, and a tabu search-based algorithm is used with the embedded BPNN-based SWMM to optimize the planning solution. The developed method is applied to the Zhong-He District, Taiwan. Results demonstrate that the application of tabu search and the BPNN-based simulation model into the optimization model can effectively, accurately and fast search optimal design considering economic net benefit. Furthermore, the optimized spatial rain barrel design could reduce 72% of inundation losses according to the simulated flood events. [ABSTRACT FROM AUTHOR]

Given the importance of achieving substantial water and operation savings, automated irrigation management has evolved toward integration of soil moisture measurements with simulation models. The main objective of this study was to develop a set of procedures to maximize irrigation efficiencies in linear-move irrigation systems. A system of field truth data collection and spatially distributed, physically based hydrological modeling was developed to evaluate the efficiencies of linear-move systems considering various naturally occurring boundary conditions and management options. Interactions among the irrigation flow depth, the evaporation conditions, the net infiltration depth and soil moisture uniformity, the irrigation turn duration and runoff-runon production were considered. Environments were of the semiarid Patagonian Monte at varying field slope and antecedent soil moisture. Plot experiments on infiltration and overland flow were used to calibrate a modified version of the CREST hydrological model adapted to the simulation of linear-move irrigation. Modeling results show that irrigation efficiencies can be improved by allowing runoff-runon to occur to an extent compatible with adequate soil moisture uniformity at the end of the irrigation turns. High efficiencies in both attaining effective infiltration depths and minimizing irrigation turn durations may be reached by adjusting the irrigation flow depth through the advance velocity of the irrigation system and/or inter-nozzle distances with due consideration to the antecedent soil moisture condition and the field slope. [ABSTRACT FROM AUTHOR]

Most available water resources in the world are used for agricultural irrigation. Whilst this level of water use is expected to increase due to rising world population and land use, available water resources are expected to become limited due to climate change and uneven rainfall distribution. Recycled stormwater has the potential to be used as an alternative source of irrigation water and part of sustainable water management strategy. This paper reports on a study to investigate whether a sustainable urban drainage system (SUDS) technique, known as the pervious pavements system (PPS) has the capability to recycle water that meets irrigation water quality standard. Furthermore, the experiment provided information on the impact of hydrocarbon (which was applied to simulate oil dripping from parked vehicles onto PPS), leaching of nutrients from different layers of the PPS and effects of nutrients (applied to enhance bioremediation) on the stormwater recycling efficiency of the PPS. A weekly dose of 6.23 × 10−3 L of lubricating oil and single dose of 17.06 g of polymer coated controlled-release fertilizer granules were applied to the series of 710 mm × 360 mm model pervious pavement structure except the controls. Rainfall intensity of 7.4 mm/h was applied to the test models at the rate of 3 events per week. Analysis of the recycled water showed that PPS has the capability to recycle stormwater to a quality that meets the chemical standards for use in agricultural irrigation irrespective of the type of sub-base used. There is a potential benefit of nutrient availability in recycled water for plants, but care should be taken not to dispose of this water in natural water courses as it might result in eutrophication problems. [ABSTRACT FROM AUTHOR]

Water is essential for all life. There is seasonal water scarcity in Marigat Division and the water demand has been increasing for both human and animal needs. In the area, there is plenty of water during rainy season most of which go to waste and frequently causes havoc due to lack of appropriate harvesting technologies. The wastage of water during rainy season can be salvaged with improved storage and rainwater harvesting methods. Such water can be available during periods of water shortages for domestic and livestock use. The study assessed the potential of the community in the area to participate in the task that aims to improve water supply. The sampling procedure was based on stratified random sampling size of 383 household heads and 10 key informants. Questionnaires were distributed to the household heads using stratified random sampling while interview schedule was used to obtain information from Focus Group Discussion (FGDs) and key informants. From the findings, the community is willing to mobilize themselves and harness the surface water runoff and the association between water scarcity and willingness of the community to harvest surface water was statistically significant (p<0. 0246). [ABSTRACT FROM AUTHOR]

Recycling irrigation water is a common practice at ornamental plant nurseries for conserving water; however, it poses the risk of sourcing and dispersing waterborne plant pathogens, especially species of Phytophthora. Slow sand filtration is a water treatment process that can remove pathogens from water, but the slow rate of water treatment may limit its application at nursery operations. In this study, four novel substrates (crushed brick, calcined clay, polyethylene beads, and Kaldnes® medium) in addition to sand were examined to determine how effective each substrate was at removing zoospores of Phytophthora nicotianae from water. The effects of substrate physical parameters, substrate depths (0, 5, 10, 20, 40, and 60 cm), and microbe density (after nursery effluent was recirculated through each substrate for 21 days) on zoospore removal by each substrate were quantified. Sand was the most effective physical filter and supported development of the best biological filter for removing zoospores. Sand columns 40 and 60 cm deep removed zoospores completely using physical filtration alone, and zoospore removal by sand at 10- and 20-cm depths was increased with the addition of biological filtration. Kaldnes® medium and polyethylene beads were the least effective filtration substrates under all conditions tested. After 21 days of recirculating nursery effluent through substrate columns, microbe density in and zoospore removal by all substrates increased. With further optimization, crushed brick may have potential to be utilized as a recycled material for a slow filtration system focused on removing plant pathogens from irrigation water. [ABSTRACT FROM AUTHOR]

Closely integrated research between archaeologists and ecologists provides a long-term view of human land use that is rare in the ecological literature, allowing for investigation of activities that lead to enduring environmental outcomes. This extended temporal perspective is particularly important in aridlands where succession occurs slowly and ecosystem processes are mediated by abiotic, geomorphic factors. Numerous studies show that impacts from ancient human actions can persist, but few have explored the types of practices or mechanisms that lead to either transient or long-term environmental change. We compared plant and soil properties and processes from a range of landscape patch types in the Sonoran Desert of the US Southwest that supported different, well-documented prehistoric farming practices from AD 750-1300. Our results show that the types of ancient human activities that leave long-term ecological legacies in aridlands are those that fundamentally alter 'slow variables' such as soil properties that regulate the timing and supply of water. Prehistoric Hohokam floodwater-irrigation practices, but not dryland farming techniques, substantially altered soil texture, which was strongly associated with desert plant community and functional composition. However, prehistoric agriculture did not consistently alter long-term nutrient availability and thus had no impact on 'fast variables' such as production of seasonal annual plants that are restricted to periods of ample rainfall. In this arid ecosystem, the inverse texture model explained patterns in plant functional composition at large scales, but is less predictive of production of short-lived desert annuals that experience a more mesic precipitation regime. [ABSTRACT FROM AUTHOR]

Abstract: Although forestation has been encouraged worldwide for the benefit of forest ecosystem services, it can lead to a reduction in runoff. As site conditions also strongly contribute to this runoff reduction, site selection has been suggested in order to mitigate this negative effect of forestation. Up to now it is not clear, however, which catchment parameters play key roles in the water budget and runoff responses to forestation. In this study, two plots within an experimental basin in the Liupan Mountains, NW China, were chosen, and the eco-hydrological model BROOK90 (Version 3.25) was used to quantify the effects of slope (gradient, aspect) and soil (thickness) parameters on water flow after forestation. The simulation showed that the annual flow in a larch plantation was strongly affected by soil thickness and lightly affected by aspect and gradient. When the soil thickness increased from 30cm to 70cm, the annual flow in the larch plantation rapidly declined from 91mm/yr to 56mm/yr. When the soil depth was greater than 70cm, however, the annual runoff was no longer sensitive to soil thickness. With respect to a forestation strategy, this means that trees preferentially should be planted on sites with thinner soil so as to lessen the impact of runoff reduction after forestation and, thus, alleviate the forest-water conflicts in dryland regions. The trade-off between a possible reduction in tree-growth on thinner soil on the one hand and an increase in runoff on the other, however, remains an open question for future interdisciplinary research. [Copyright &y& Elsevier]

Abstract: Transport of dissolved organic matter in runoff water plays a critical role in the increased inputs of nutrients (N and P) and metals (Fe, Cu and Zn) in water, and the deposition of muck sediments in the Saint Lucie Estuary and Indian River Lagoon, Florida. The objectives of this study were to investigate the variation of dissolved organic carbon (DOC) and dissolved nitrogen (DN) in surface runoff water with varying land uses, and to explore their possible relations with the leaching losses of nutrients N and P, and metals Fe, Cu, and Zn from different land uses. For this, surface runoff water from two major agricultural production systems (citrus grove and vegetable farm) in south Florida was collected weekly using pre-installed autosamplers during Jan. 2008–Mar. 2010. Meanwhile, runoff water from twelve field sites with varying land uses (such as ranch, golf course, and forest) was collected monthly using a grab sampler from Aug. 2008 to April, 2010, and soils were collected at the depth of 0–15cm and 15–30cm twice a year from autosampler-installed locations and on Nov. 25th, 2008 from grab sampling locations as well. In the field, water samples were measured for electrical conductivity, dissolved oxygen, and temperature; in the laboratory, water samples were analyzed for pH, total solids, turbidity, DOC, DN, total P (TP), and metals Cu, Fe and Zn with or without passing a 0.45μm filter membrane. After passing a 2mm sieve, fresh soil samples were analyzed for moisture, pH, electrical conductivity, 0.5M K2SO4 solution extractable DOC/DN, and Mehlich 3 extractable P, Fe, Cu, and Zn. Spatial and temporal variations in the concentrations of DOC and DN in runoff water were observed, with the greatest average concentrations of DOC and DN from ranch (∼28 and ∼2.3mgL−1) and the lowest from golf course (∼16mgL−1) for DOC and from forest and nursery for DN (∼1.5–1.6mgL−1), respectively. Temporal fluctuations of DOC and DN in runoff water from varying land uses were in good accord with rainfall intensity and frequency of rainfall. Temporal variations of TP and metals Fe, Cu, and Zn were influenced by climatic condition as well. Citrus grove exported greater amounts of DOC and DN in runoff water (27.6 and 3.51mgL−1 of median value) than vegetable farms (13.8 and 2.26mgL−1 of median value). Annual cumulative loads of DOC and total N in 2008, 2009 or 2010 were >20kgha−1, greater than those of TP (<13.5kgha−1) and metals Fe, Cu, and Zn (<1.5kgha−1). Ranch soil had the highest extractable DOC concentration (>100mgkg−1), accounting for 1% of its total organic carbon. Soil extractable DN had significant correlations with extractable P and Cu/Zn in soils. In conclusion, soil total organic carbon pool and its availability had an important effect on DOC and DN in runoff water. Land use type and rainfall event were the two influential factors affecting concentrations of DOC and DN, and the export of nutrients N and P, and metals in runoff water. [Copyright &y& Elsevier]

Abstract: The performance of furrow irrigation systems in terms of application efficiency, runoff ratio, and water requirement efficiency were evaluated at nine different sites within the Provinces of Fergana (6 sites) and Andijon (3 sites) in Uzbekistan. A total of 46 irrigation events were evaluated during the year 2009, whereas only a total of 8 irrigation events (at 3 sites) were evaluated during the year 2010. Most of the selected fields have slopes greater than 0.005; hence, the average runoff volume from these fields was 39% of the total volume of water applied to the fields, indicating problems with selection of appropriate furrow flow rates under the given set of field conditions. For several fields, the seasonal volume of water applied was significantly different than the irrigation norms specified for the site. Though some of the farmers followed the irrigation advisory service on when to irrigate, there was a large mismatch between the volume of water applied and the volume of water deficit within the crop root zone. Reliability, in terms of magnitude and duration of flow rate received at the fields, was a major issue at all the sites. Considerable fluctuations were observed in the flow rates received at all the field sites during each irrigation event. In addition, the average flow rate received at the field sites varied considerably between irrigation events making it difficult for farmers to manage irrigation water. Farmers that had high watertable (less than 100cm from the ground surface) still applied large volumes of water, resulting in low application efficiency. Several recommendations for improving the performance of furrow irrigation systems in Uzbekistan are provided. [Copyright &y& Elsevier]

The article discusses the traditional rice irrigation method in northeastern Thailand with particular focus given to the earthen weirs, locally known as thamnop. According to the article, the thamnop is designed to divert the entire river runoff into riverbanks and is built on rivers with no destructive flush runoff or storm flow.

ABSTRACT Lake Elton is located east of the Volga River in Russia and covers an area of 155 km2. The hydrological system of the Lake and its surroundings are extremely vulnerable to climate change and human interference, but available local and regional information is sparse. Utilising climate data from 1987 to 2009 and surface albedo readings from the MODerate resolution Imaging Spectroradiometer satellite since 2000, this study analyses Lake degradation processes since 2005. Lake surface albedo analysis indicates that during the past 6 years, lake albedo has increased dramatically from average peak values of 0·14 to 0·40. In addition, air temperature has increased by 2 °C, and annual precipitation has decreased by 40 per cent. Moreover, human intervention in the area has increased environmental pressure on the Lake, causing a reduction of runoff inflow because of water capture, use of check-dams and water-harvesting systems. The results of the study show that, under current conditions, the Lake surface albedo is likely to remain high as compared with previous observations. The current trend implies an average 2 per cent per year increase in future annual albedo, with a maximum possible increase of 4 per cent up to a steady state of salt-crust albedo values. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Abstract: Water performs essential ecological functions in agroecosystems and supplies an array of hydrologic ecosystem services (HES). The nature and quantity of HES is intimately linked with the management of the territory, and the capacity of the different land uses to partition rainfall into green (evapotranspiration) and blue (runoff) freshwater flows. This paper presents an innovative method to empirically assess the underlying relationship between the use and management of Mediterranean agroecosystems, their spatial pattern of green and blue freshwater flow generation and the provision of HES. We test this approach in Sierra Norte de Sevilla, a characteristic Spanish agro-forestry system. To assess the hydrological functioning we used the spatially explicit hydrologic model BalanceMED. HES’ identification and societal valuation was done through an expert panel. The hydrologic performance and the social values ascribed to the different services were combined to identify key provisioning areas or HES hotspots. Our results show that multifunctional agroecosystems, where agrarian and forestry activities co-exist, optimize the partition and use of freshwater flows and supply the largest bundles of HES at a wide range of spatial scales. The often low profitability of these extensive activities is prompting either the intensification or the abandonment of many Mediterranean agro ecosystems. We discuss the trade-offs in HES associated with these land use trends, and we illustrate the potential options available for implementing payments for ecosystem services (PES) schemes to pursue “win–win” management solutions. [Copyright &y& Elsevier]

Dublin Institute of Technology personnel were commissioned in 2005 by the Department of Environment, Heritage and Local Government in Ireland to assess the feasibility of utilizing harvested rainwater to replace treated mains water, for nonpotable uses. A pilot project was set up. The project involved the design, installation, commissioning and monitoring of rainwater harvesting facilities in a rural housing development. A monitoring programme was carried out to examine the physicochemical and microbiological quality of the harvested rainwater. Harvested rainwater was sampled monthly and tested. Analysis of the harvested rainwater quality showed a consistently high quality of raw water in general compliance with the requirements of the European Communities (Quality of Bathing Water) Regulations for 100% of samples and the European Communities (Drinking Water) Regulations, 2007 for 37% of sampling dates. [ABSTRACT FROM AUTHOR]

The SOFTANK model optimally designs the watershed-based tank system by simulating field, tank, and groundwater balances. We applied this model to a small watershed consisting of six tanks (small reservoirs) in the semiarid region of India. We evaluated the existing tank system in this watershed and compared it to a one-tank system. Results showed that one tank at the outlet of the watershed would have been more beneficial [with benefit-cost (BC) ratio of 1.80] than the existing six-tank system (with BC ratio of 1.71). Finally, we performed the analysis for obtaining the optimal tank system for the watershed, and we found that the tanks for irrigation purposes are not economical for the small watershed. The groundwater source was enough for irrigation, so any additional investment in the tanks would be uneconomical. The results demonstrate the importance of the watershed-based tank system approach to design. [ABSTRACT FROM AUTHOR]

The article offers information on the Marine Street program for the water front streets in New York City as design approach in ecological restoration. It states that the program aims to replace the asphalt structures with Marine Streets, Sloped Street, and Park Marine Street for control storm water runoff and storm surges and sustainability. Policy issues related to the program are also discussed.

In the arid Southwest, water is a limiting resource. Rainwater harvesting is garnering favor, but many are unaware of the myriad uses for that water. Access to fresh, healthy food is also limited in many rural counties because the arid climate makes farming conditions difficult. Teaching youth gardening with rainwater increases the accessibility of local food and the importance of capturing water that might go unused. A series of videos made in youth and adult partnerships provides a tutorial for project duplication worldwide. [ABSTRACT FROM AUTHOR]

Bacterial communities were profiled through two drilled soil cores below an infiltration basin that receives highway runoff and de-icing agents. Analyses of groundwater dissolved oxygen, physical and chemical properties of the soil complemented molecular phylogenetic determinations to distinguish ambient and contaminated plume zones. The bacterial community was previously characterized (when the site received high levels of acetate as de-icing agent) by being dominated by members of Geobacteraceae family. In this study, bacterial 16S rDNA gene clones showed highly diverse microbial communities, both into the plume and in the ambient aquifer, in which Geobacter spp. represents only a small fraction of them. The clones were affiliated with 32 and 23 classes identified from the sediment cores along the contaminant plume. The plume in the infiltration basin was anaerobic and iron-reducing, while the sediments in the underlying ambient aquifer were dominated by aerobes due to the presence of aerated ambient groundwater. These data indicate shifts in microbial communities in correlation with depth, substrate and oxygen availability in a de-icing agent impacted subsurface. [ABSTRACT FROM AUTHOR]

For the purpose of assessing the potential influence of tropical rain forest conversion to rubber plantation on catchment hydrology, a stable oxygen isotope was used as a tracer to identify the event water and prestorm water components of storm runoff during low- and high-flow conditions in a native tropical rain forest catchment (TRFC) and an artificial rubber plantation catchment (ARPC) in SW China. Isotopic hydrograph separations for the storm of April and September 2004 reveal that the event water made up only a small proportion of discharge (29 and 31%, respectively) at peak flow in the TRFC, while it made up the dominant component at peak flow (62 and 69%, respectively) in the ARPC. The analyses suggest that in the ARPC, the universal presence of compacted terraced tracks associated with land management would encourage infiltration-excess overland flow. This isotopic investigation demonstrates that tropical rain forest conversion to rubber plantation would markedly change the runoff generation processes in this area. [ABSTRACT FROM AUTHOR]

Abstract: Jordan is characterised as a ‘water scarce’ country. It is considered as one of the lowest countries in the world on a per capita basis. The available water resources per capita are falling as a result of population growth and are projected to fall from less than 160m3 per capita per year at present to about 90m3 per capita per year by 2025. Water harvesting has been practiced in Jordan for thousands of years. There are indications of early water harvesting structures believed to have been constructed over 9000 years ago. There is a need to establish water harvesting projects at various places in Jordan to collect more surface water for domestic, agricultural and livestock watering usages. The selection of best sites for water harvesting schemes must be based on certain criteria that take into consideration the socio-economic and the physical characteristics of the targeted area. This research aimed to use both the Weighted Linear Combination and the Boolean techniques within GIS environment to select suitable areas in Northern Jordan for establishing water harvesting ponds. This resulted in having ca. 25% of the study area (64,184.8ha) with high potential for constructing water harvesting ponds. [Copyright &y& Elsevier]

The article presents a study which examines the deposition of chlorothalonil, a broad-spectrum foliar fungicide, on nontarget ground surfaces coming from commercial foliage plant nursery. The study involves the process of irrigation runoffs of water samples that were collected and analyzed for the foliar fungicide. It reveals the significance of plant size, spacing, and row lengths to the percentage of the fungicide on nontarget ground surfaces. Moreover, it shows that the percentage of total nontarget deposition of chlorothalonil reached 0.25% to 0.53% in runoff water.

With increasing development in areas of trout sensitive waters, the effect of urban storm-water runoff temperature on the aquatic ecosystem has become a concern. A study was conducted in western North Carolina, along the southeastern extent of U.S. trout populations, to determine the effect of storm-water wetlands and wet ponds on the temperature of urban storm-water runoff. Measurements included temperature at the inlets, outlets, and at several depths within the best management practices (BMPs). Parking lot runoff temperatures were significantly higher than the 21°C temperature threshold for trout during peak summer months and water temperatures consistently increased from the inlet to the outlet in the storm-water wetland and wet pond, implicating these BMPs as sources of thermal pollution. Despite similar inflow temperatures, effluent temperatures from the wet pond were significantly warmer than those from the storm-water wetland for the period from June to September. Substantial cooling was observed as runoff was conveyed from the parking surface to the BMPs through buried pipes, which could be incorporated into BMP design to achieve thermal pollution mitigation goals. Temperatures at the bottom of the water columns were cooler than water leaving the current outlet structures, providing support for the installation of modified outlet structures in regions with cold water fisheries. [ABSTRACT FROM AUTHOR]

A grid-based erosion model is developed by integrating the distributed hydrological model, BTOPMC, with the modified USLE to estimate soil erosion and sediment outflow during single storms. The possible sheet, rill, channel erosion types, and sediment transport processes are considered within each grid under the model structure. Instead of representing the sheet erosion and rill erosion separately, the classic USLE method is modified to simulate the lumped sheet–rill erosion during storms. In the modification, the runoff ratio and a relevant correction coefficient are brought into the R-factor which improves the model’s applicability in predicting erosion during single storms. Instead of representing a grid with a unique erosion type, a channel component is assumed to exist in each grid, and its width varies with the upstream contributing area of the grid. This assumption avoids the problems that are caused by the difference between the channel widths in the upstream area and the downstream area if the grid is simply recognized as a channel grid. It also enables the model to be applicable in simulating soil erosion and sediment outflow from a large catchment. Through a case study in the Lushi catchment, China, the results show an overall satisfactory accuracy for the selected events. Moreover, by analyzing the spatial distribution of soil erosion or deposition, the erosion-prone areas are identified for the prioritization purpose. [ABSTRACT FROM AUTHOR]

Woltemade, Christopher J., 2010. Impact of Residential Soil Disturbance on Infiltration Rate and Stormwater Runoff. Journal of the American Water Resources Association (JAWRA) 46(4): 700-711. DOI: 10.1111/j.1752-1688.2010.00442.x Soil disturbances such as excavation and compaction in residential developments affect lawn infiltration rates and stormwater runoff. These effects were investigated via measuring saturated infiltration rates at 108 residential sites and 18 agricultural sites near Shippensburg, south-central Pennsylvania, using a double-ring infiltrometer. Residential sites included four neighborhoods distributed across three soil series classified as hydrologic soil group (HSG) B. Additional parcel data included date of house construction, percentage impervious area, lawn condition, and woody vegetation condition. Measured infiltration rates ranged from 0 to >40 cm/hour. Analysis of variance indicated significantly different mean infiltration rates ( p < 0.001) for lots constructed pre-2000 (9.0 cm/hour) and those constructed post-2000 (2.8 cm/hour). Test results were used to determine a “field-tested” HSG for each site, representing disturbed soil conditions. Stormwater runoff was estimated from residential lots for a range of 24-hour design storms using the TR-55 model and several alternative methods of determining curve numbers, including five different representations of soil conditions. Curve numbers and stormwater runoff were substantially higher when based on field-tested HSGs for lots constructed post-2000 compared with lots built pre-2000 and when based on the HSG for undisturbed soils, documenting the magnitude of possible error in stormwater runoff models that neglect soil disturbance. [ABSTRACT FROM AUTHOR]