BASIN SCALE WATER MANAGEMENT AND FORECASTING USING ARTIFICIAL NEURAL NETWORKS1

ABSTRACT: Water scarcity in the Sevier River Basin in south‐central Utah has led water managers to seek advanced techniques for identifying optimal forecasting and management measures. To more efficiently use the limited quantity of water in the basin, better methods for control and forecasting are imperative. Basin scale management requires advanced forecasts of the availability of water. Information about long term water availability is important for decision making in terms of how much land to plant and what crops to grow; advanced daily predictions of streamflows and hydraulic characteristics of irrigation canals are of importance for managing water delivery and reservoir releases; and hourly forecasts of flows in tributary streams to account for diurnal fluctuations are vital to more precisely meet the day‐to‐day expectations of downstream farmers. A priori streamflow information and exogenous climate data have been used to predict future streamflows and required reservoir releases at different timescales. Data on snow water equivalent, sea surface temperatures, temperature, total solar radiation, and precipitation are fused by applying artificial neural networks to enhance long term and real time basin scale water management information. This approach has not previously been used in water resources management at the basin‐scale and could be valuable to water users in semi‐arid areas to more efficiently utilize and manage scarce water resources.     

Biochar as low-cost sorbent of volatile fuel organic compounds: potential application to water remediation

Pyrolysis of waste materials to produce biochar is an excellent and suitable alternative supporting a circular bio-based economy. One of the properties attributed to biochar is the capacity for sorbing organic contaminants, which is determined by its composition and physicochemical characteristics. In this study, the capacity of waste-derived biochar to retain volatile fuel organic compounds (benzene, toluene, ethylbenzene and xylene (BTEX) and fuel oxygenates (FO)) from artificially contaminated water was assessed using batch-based sorption experiments. Additionally, the sorption isotherms were established. The results showed significant differences between BTEX and FO sorption on biochar, being the most hydrophobic and non-polar contaminants those showing the highest retention. Furthermore, the sorption process reflected a multilayer behaviour and a relatively high sorption capacity of the biochar materials. Langmuir and Freundlich models were adequate to describe the experimental results and to detect general differences in the sorption behaviour of volatile fuel organic compounds. It was also observed that the feedstock material and biochar pyrolysis conditions had a significant influence in the sorption process. The highest sorption capacity was found in biochars produced at high temperature (>?400 °C) and thus rich in aromatic C, such as eucalyptus and corn cob biochars. Overall, waste-derived biochar offers a viable alternative to be used in the remediation of volatile fuel organic compounds from water due to its high sorption capacity.

     

Enhanced activated persulfate oxidation of ciprofloxacin using a low-grade titanium ore under sunlight: influence of the irradiation source on its transformation products

Environmental Science and Pollution Research - In this work, the activated persulfate oxidation of ciprofloxacin (CIP) using a low-grade titanium ore under sunlight or simulated sunlight were...     

Echolocation calls of Poey’s flower bat (<Emphasis Type="Italic">Phyllonycteris poeyi</Emphasis>) unlike those of other phyllostomids

Unlike any other foraging phyllostomid bat studied to date, Poey’s flower bats (Phyllonycteris poeyi-Phyllostomidae) emit relatively long (up to 7.2 ms), intense, single-harmonic echolocation calls. These calls are readily detectable at distances of at least 15 m. Furthermore, the echolocation calls contain only the first harmonic, which is usually filtered out in the vocal tract of phyllostomids. The foraging echolocation calls of P. poeyi are more like search-phase echolocation calls of sympatric aerial-feeding bats (Molossidae, Vespertilionidae, Mormoopidae). Intense, long, narrowband, single-harmonic echolocation calls focus acoustic energy maximizing range and favoring detection, which may be particularly important for cruising bats, like P. poeyi, when flying in the open. Flying in enclosed spaces, P. poeyi emit short, low-intensity, frequency-modulated, multiharmonic echolocation calls typical of other phyllostomids. This is the first report of a phyllostomid species emitting long, intense, single-harmonic echolocation calls with most energy in the first harmonic.     

Optimization of circular plate separators with cross flow for removal of oil droplets and solid particles

A circular gravity-phase separator using coalescing medium with cross flow was developed to remove oil and suspended solids from wastewaters. Coalescence medium in the form of inclined plates promotes rising of oil droplets through coalescence and settling of solid particles through coagulation. It exhibits 22.67% higher removal of total suspended solids (TSS) compared to separators without coalescing medium. Moreover, it removed more than 70% of oil compared to conventional American Petroleum Institute separators, which exhibit an average of 33% oil removal. The flowrate required to attain an effluent oil concentration of 10 mg/L (Q(o10)) at different influent oil concentrations (C(io)) can be represented by Q(o10) x 10(-5) = -0.0012C(io) + 0.352. The flowrate required to attain an effluent TSS concentration of 50 mg/L (Q(ss50)) at different influent TSS concentrations (C(iss)) can be represented by Q(ss50) x 10(-5) = 1.0 x 10(6) C(iss)(-2.9576). The smallest removable solid particle size was 4.87 microm.     

Comparative Influence of Forest Management and Habitat Structural Factors on the Abundances of Hollow-Nesting Bird Species in Subtropical Australian Eucalypt Forest

We examined the impact of single-tree selective logging and fuel reduction burns on the abundance of hollow-nesting bird species at a regional scale in southeastern Queensland, Australia. Data were collected on species abundance and habitat structure of dry sclerophyll production forest at 36 sites with known logging and fire histories. Sixteen bird species were recorded with most being resident, territorial, obligate hollow nesters that used hollows that were either small (<10 cm diameter) or very large (>18 cm diameter). Species densities were typically low, but combinations of two forest management and three habitat structural variables influenced the abundances of eight bird species in different and sometimes conflicting ways. The results suggest that habitat tree management for biodiversity in production forests cannot depend upon habitat structural characteristics alone. Management histories appear to have independent influence (on some bird species) that are distinguishable from their impacts on habitat structure per se. Rather than managing to maximize species abundances to maintain biodiversity, we may be better off managing to avoid extinctions of populations by identifying thresholds of acceptable fluctuations in populations of not only hollow-nesting birds but other forest dependent wildlife relative to scientifically valid forest management and habitat structural surrogates.     

Ultraviolet-based female preferences in a viviparous fish

Studies on fish have demonstrated female-mating preferences based on dimorphic colours and colour patterns, but commonly focused on the 400-700 nm (visible) band. In experiment 1 we exposed females of the amarillo (Girardinichthys multiradiatus), a viviparous fish with visually based female mate choice, to two views of males either containing (UV+) or lacking (UV-) information in the 300-400 nm region. Experiments were conducted outdoors, and we found that females spent more time next to the male seen through the UV+ filter than the same seen through the UV- filter. Since the two images only differed in the content of UV radiation, we conclude that females of the amarillo can detect UV light. Experiments 2 and 3 were designed to test whether such an effect can be attributed to female preferences based on the males' UV-reflecting colour patterns. We first assessed which area(s) of the fish have UV-reflecting properties. Then, using an opaque gelatine powder to block skin reflectance, we found that, in the presence of environmental UV light, females spend more time close to the males with powder sprinkled outside the UV-reflecting area (control) than to the males with powder sprinkled over the UV-reflecting area (experiment 2). This could have been due to the concealment of signals in the visible spectrum, rather than in the UV spectrum; thus we repeated the same experiment indoors, in the absence of UV light (experiment 2b); here females failed to discriminate between males. Since we also found that females have UV-reflecting areas in their flanks, we conducted a third experiment to test whether the preferential association of females found in the first experiment was due to the tendency to school/associate with conspecifics, rather than to mate choice (experiment 3). We found no evidence of discrimination in this experiment. We conclude that the UV markings and vision in G. multiradiatus have a function in female mate choice. This is the first time that evidence has been found for the influence of UV for mate choice in fish.     

Dealing with urban noise: vermilion flycatchers sing longer songs in noisier territories

In noisy conditions, several avian species modulate their songs in amplitude and in the temporal or frequency domains, presumably to improve communication. Most studies on how passerine birds perform such adjustments have been carried out in oscines, a group well known for the importance of learning in the development of their songs. On the other hand, suboscines, in which learning appears to have little influence on the development of their songs, have been largely neglected. We evaluated song adjustment to noise in the vermilion flycatcher (Pyrocephalus rubinus), a suboscine bird. We conducted song recordings and noise measurements at several territories within Mexico City during the length of the dawn chorus. Males living in noisier places sang long songs, while those males inhabiting quieter places sang both short and long songs. We also found evidence of individual song plasticity, as males sang less versatile songs (i.e., songs with more introductory elements) later in the morning when noise levels were higher. This individual shift in song seems to be more associated to time of the day rather than to the observed rise in noise. However, we cannot discard an effect of noise, which should be evaluated with an experiment. We discuss our results in the context of other studies with oscine passerines and other taxa and consider implications for signaling in intra- and intersexual contexts.