Stormwater Runoff Pollutant Loading Distributions and Their Correlation with Rainfall and Catchment Characteristics in a Rapidly Industrialized City

Fast urbanization and industrialization in developing countries result in significant stormwater runoff pollution, due to drastic changes in land-use, from rural to urban. A three-year study on the stormwater runoff pollutant loading distributions of industrial, parking lot and mixed commercial and residential catchments was conducted in the Tongsha reservoir watershed of Dongguan city, a typical, rapidly industrialized urban area in China. This study presents the changes in concentration during rainfall events, event mean concentrations (EMCs) and event pollution loads per unit area (EPLs). The first flush criterion, namely the mass first flush ratio (MFFn), was used to identify the first flush effects. The impacts of rainfall and catchment characterization on EMCs and pollutant loads percentage transported by the first 40% of runoff volume (FF₄₀) were evaluated. The results indicated that the pollutant wash-off process of runoff during the rainfall events has significant temporal and spatial variations. The mean rainfall intensity (I), the impervious rate (IMR) and max 5-min intensity (I_max5) are the critical parameters of EMCs, while I_max5, antecedent dry days (ADD) and rainfall depth (R_D) are the critical parameters of FF₄₀. Intercepting the first 40% of runoff volume can remove 55% of TSS load, 53% of COD load, 58% of TN load, and 61% of TP load, respectively, according to all the storm events. These results may be helpful in mitigating stormwater runoff pollution for many other urban areas in developing countries.     

Effect of High Flow Events on In-Stream Dissolved Organic Nitrogen Concentration

Dissolved organic nitrogen (DON) can comprise a large and biologically important fraction of total dissolved N in surface water. Biotic and abiotic processes result in heterogeneous DON concentrations and bioavailability in soils, and as hydrologic connectivity expands and flow paths change in watersheds, novel sources of DON can be mobilized and transported to surface water. Although the relationship between in-stream DOC concentration and stream discharge has previously been examined in the literature, up to now there has not been a synthesis examining how DON concentrations, loads, and composition change during transitions from base flow to pulse flow conditions. We present a meta-analysis examining the effect of high flow on DON concentration ([DON]). The ratio of mean pulse flow [DON] to mean base flow [DON] (P:B) was calculated for individual events and averaged (geometric) within and then across sites to generate an overall effect size. For 47 sites (78 events), mean P:B was 1.58, which was significantly different from unity. This moderate increase in DON concentration contributed to over a more than 10-fold average increase in the rate of DON yield from base flow to high flow. The response of [DON] to high flow was significant in catchments where individual storm events or snowmelt runoff events were responsible for elevated flows, whereas the response was not significant in catchments where high discharge resulted from a mixture of upstream snowmelt and rain events. Additionally, an examination of DOC:DON ratios during high flow indicates that multiple sources of DON may be mobilized during high flow. Finally, current models of annual DON export may be improved by including a positive relationship between discharge and DON.     

HLA phenotype and haplotype frequencies in the Cantabria (middle north Spain) population.

The gene and haplotype frequencies of the HLA-A and -B locus antigens were determined in 502 unrelated individuals from Cantabria (middle North Spain). Our results were compared with those reported for other European and Spanish populations. The haplotypes with significant linkage disequilibrium were also analyzed in various Spanish population samples in order to establish possible relationships with geographic situation and historical events.     

Scaling of in vivo muscle velocity during feeding in the largemouth bass, Micropterus salmoides (Centrarchidae)

Many vertebrates undergo large increases in body size over the course of a lifetime, and these increases are often accompanied by changes in morphological and physiological parameters. For instance, in most animals, increases in size with growth are accompanied by decreases in the maximum speed of shortening (V(max)) in locomotor muscles. Curiously, in muscles involved in suction feeding, V(max) shows no decreases with size in vitro, despite the fact that timing of kinematic events involved in suction feeding (e.g., time to peak gape) slow with increased size. The goal of this study was to examine whether muscular speed in vivo varies with size during suction feeding in the largemouth bass (Micropterus salmoides). The dorsal epaxial musculature of 10 individual bass (varying from 123 to 685 g and from 18.1 to 32.0 cm standard length [SL]) was implanted with sonometric crystals to measure muscle length during feeding on elusive prey (large goldfish). No relationship was found between the mean individual or maximum speed of shortening with mean individual log-transformed SL. However, mean magnitude of shortening and maximum shortening magnitude showed nonsignificant increases with SL ([Formula: see text] and 0.06, respectively). Average duration of shortening was found to increase with log-transformed SL. The size invariance of observed shortening velocity in the epaxial muscles during feeding may stem from size invariance of imposed loads during suction feeding. This is in contrast to what is normally seen in locomotor systems where loads on muscles often increase with body size.     

Canonical variables of aquatic bryophyte combinations for predicting water trophic level

Concentrations of soluble reactive phosphorus (SRP), nitrate, and soluble reactive silicon (SRSi) were monitored in 12 streams draining small catchments (<10 km2) in the English Lake District. The catchments varied with respect to underlying geology, soil type and land cover. Average concentrations of SRP were in the range 0.5–11.2 μg P l-1, and estimated loads ranged from 0.01 to 0.14 kg P ha-1 a-1. The higher concentrations and loads were associated with catchments containing improved pasture. Mean streamwater concentrations of nitrate varied from 55 to 660 μg N l-1, while loads were in the range 0.8–9.6 kg N ha-1 a-1; no general dependence on catchment properties was discerned. Concentrations of SRSi were similar in all the streams (0.8–2 mg Si l-1), and annual loads were in the range 10–26 kg Si ha-1 a-1. Loads of all three nutrients were greatest during the winter, because of higher discharges, but in some catchments containing improved pasture, considerable transport of P also took place during the summer. Concentrations of nitrate in streams draining unimproved moorland catchments are approximately twice those reported for samples taken from similar streams in 1973 and 1974, possibly because of increased atmospheric deposition of inorganic nitrogen (ammonium and nitrate). Concentrations of SRP in such streams were similar to those reported for the earlier samples. Comparisons of stream loads of SRP and nitrate with estimated inputs suggest that catchment soils retain substantial amounts of these nutrients. Implications for surface water eutrophication of changes in P retention by soils are discussed. This revised version was published online in July 2006 with corrections to the Cover Date.     

The influence of climate changes in Platanus spp. pollination in Spain and Italy

There is evidence of a significant increase in air temperature in the northern hemisphere over recent decades, with consequent changes for anemophilous pollen. In this work we present the effects of climatic change on Platanus spp. pollination in different areas of Italy and Spain, characterized by different climates. In particular, the historical series of pollen monitoring and meteorological data of two Italian stations, Perugia (1982 – 2003) and Torino (1985 – 2003), and two Spanish stations, Santiago de Compostela (1992 – 2003) and Vigo (1994 – 2003), were analysed. The changes recorded in all stations included the timing and behaviour of pollen release. However, no or minimal influence on the total pollen emission was found. Research has linked the changes in phenological events to an increase in temperature, moreover in this study temperature changes are believed to be mainly responsible for the variations recorded in the pollen season of Platanus. A previous start of pollination (?0.66; ?1.21; days/year) is reported in both Italian stations where the temperatures have significantly increased and a delay of 0.2 – 0.8 days/year in Spanish stations where a different trend of temperature is recorded. Other important data is given regarding the type of discharge of pollen grains during the pollen season. Pollination curves are examined by two statistical shape parameters (kurtosis and skewness) which show that pollen release is more gradual with higher temperatures or faster under colder conditions. A regression analysis links the atmospheric pollen presence to mean air temperature.     

Wrist loading patterns during pommel horse exercises

Gymnastics is a sport which involves substantial periods of upper extremity support as well as frequent impacts to the wrist. Not surprisingly, wrist pain is a common finding in gymnasts. Of all events, the pommel horse is the most painful. In order to study the forces of wrist impact, a standard pommel horse was instrumented with a specially designed load cell to record the resultant force of the hand on the pommel during a series of basic skills performed by a group of seventeen elite male gymnasts. The highest mean peak forces were recorded during the front scissors and flair exercises (1.5 BW) with peaks of up to 2.0 BW for some gymnasts. The mean peak force for hip circles at the center or end of the horse was 1.1 BW. The mean overall loading rate (initial contact to first loading peak) ranged from 5.2 BWs-1 (hip circles) to 10.6 BW s-1 (flairs). However, many recordings displayed localized initial loading spikes which occurred during 'hard' landings on the pommel. When front scissors were performed in an aggressive manner, the initial loading spikes averaged 1.0 BW in magnitude (maximum 1.8 BW) with an average rise time of 8.2 ms; calculated localized loading rates averaged 129 BW s-1 (maximum 219 BW s-1). These loading parameters are comparable to those encountered at heel strike during running. These impact forces and loading rates are remarkably high for an upper extremity joint not normally exposed to weight-bearing loads, and may contribute to the pathogenesis of wrist injuries in gymnastics.     

Case studies of variations in suspended matter transport in small catchments

Changes of water and suspended sediment composition during three single flood events were investigated in two small catchments in the Mosel region. In addition to suspended sediment characteristics (turbidity, loss on ignition, density, chlorophyll content), several different nutrients and heavy metals were determined in the dissolved and particulate phase. The flood events investigated were characterized by a single peaked hydrograph. In contrast suspended sediment concentrations and the other parameters showed more complex behaviour. The transport of suspended sediment was not only controlled by discharge magnitude. In the course of a flood event different suspended sediment sources are activated. Using the chemograph and the timing of samples collected during the hydrograph these suspended sediment sources can be identified. In addition to the remobilization of sediment and channel erosion, inputs of suspended solids from a sewage plant, road discharge, topsoil and interflow could be identified.     

Comparison of the hydrological characteristics of three small experimental holm oak forested catchments in NE Spain in relation to larger areas

Precipitation and streamflow have been measured in three small (0.04–0.52 km²) experimental catchments covered by dense holm oak (Quercus ilex L.) forests. Two of them are in the Prades mountains and one in the Montseny mountains (NE Spain). Here we test the hydrological representativeness of these catchments against the streamflow record at two nearby larger (34–60 km²) catchments, one from each massif. Comparisons of (i) annual streamflow, (ii) seasonal distribution of streamflow, and (iii) flow duration curves were made. At Prades, for the period of common record, mean annual precipitation was about 580 mm, and mean annual streamflow 44–81 mm at the two experimental catchments and 102 mm at the larger one. Most streamflow occurred during winter and spring in the three catchments. At Montseny, rainfall was higher, and mean annual streamflow was 495 mm in the experimental catchment, and 760 mm in the larger catchment, though these data were obtained in different periods in each catchment. Streamflow was roughly equal in autumn, winter and spring. At both sites flow duration curves were fairly similar in the small experimental catchments and the larger catchments. The higher streamflow at Montseny is reflected in its flow duration curves being well above those at Prades. The experimental catchments at Prades are thus fairly representative of the larger nearby catchment for the investigated hydrological characteristics. At Montseny, hydrological differences between the experimental catchment and the larger catchment are probably due to the higher mean altitude of the latter and to the non-overlapping periods of their streamflow records.     

A combined approach of methods for determining the regional assessment of the disjunct plant Primula pedemontana in Spain

The aim of this study was to conduct a regional threat-status assessment for Primula pedemontana Thomas ex Gaudin in Spain. This is an Alpine plant with a single isolated Iberian population. A major field survey was made to monitor the species in Spain with a view to preventing its possible disappearance. For that purpose, a habitat study was carried out, regional population size and population structure were determined, and major threats and conservation actions were identified. Besides, habitat suitability maps were drawn up for the present and for 2025 and the percentage of potential habitat loss was calculated in order to estimate their possible evolution. The number of mature individuals, calculated as a trapezoidal fuzzy number, was [9179; 10820; 19002; 22342]. Extent of occurrence and area of occupancy calculated were 2.5 and 0.16 km², respectively. The regional IUCN category obtained for P. pedemontana was “Critically Endangered”. The percentage of potential habitat loss was estimated at 10.9% for 2025. The authors consider that this species is among the priority Spanish plants for conservation, and that it should be included in the “Spanish List of Wild Species under the Special Protection Scheme”.     

A risk shadow in Spain

This paper describes a period of intense risk construction in Spain. By autumn 2000 there was a coincidence of different alarming events affecting Spanish society and widely covered by media. A feeling of risk extended all around and the Spanish political agenda was, for a time, dominated by risk issues. This paper tries to establish how useful the concept of 'risk shadow' can be in order to analyse the construction of risk in a global context. The narratives of risk seem to give this phenomenon its cultural consistency, because more than a scientific fact, risk construction is a cultural matter.     

The sensitivity of Afromontane tarns in the Maloti-Drakensberg region of South Africa and Lesotho to acidic deposition

Despite their remoteness from sources of atmospheric pollutant emissions, the Afromontane tarns in the Maloti-Drakensberg region are perfect candidates to study the negative effects of acidifying atmospheric pollution, because mountain lakes are widely recognised as sentinel ecosystems, unimpacted by direct human disturbance within their catchments. Thirty-four tarns were sampled in the Maloti-Drakensberg region and most were found to be extremely sensitive to acidic deposition, as indicated by their low acid neutralising capacity. There are very few studies of freshwater critical loads for any region within South Africa. The steady-state water chemistry model (SSWC) was adapted and used to determine critical loads, whereas exceedance was estimated relative to modelled regional deposition data, in order to understand the risk of harmful effects to aquatic ecosystems. Seventy-six percent of sampled sites across the Maloti-Drakensberg would exceed critical loads even at the lowest modelled deposition levels, but there are no current measured deposition data for the region. The sensitivity of the Maloti-Drakensberg tarns needs to be considered in future policy formulation regarding acceptable levels of acidifying atmospheric pollution from South Africa’s energy sector and indicates the need for assessing aquatic ecosystem impacts in other regions of South Africa.     

The Characteristics of Extreme Erosion Events in a Small Mountainous Watershed

A large amount of soil loss is caused by a small number of extreme events that are mainly responsible for the time compression of geomorphic processes. The aim of this study was to analyze suspended sediment transport during extreme erosion events in a mountainous watershed. Field measurements were conducted in Wangjiaqiao, a small agricultural watershed (16.7 km²) in the Three Gorges Area (TGA) of China. Continuous records were used to analyze suspended sediment transport regimes and assess the sediment loads of 205 rainfall–runoff events during a period of 16 hydrological years (1989–2004). Extreme events were defined as the largest events, ranked in order of their absolute magnitude (representing the 95^th percentile). Ten extreme erosion events from 205 erosion events, representing 83.8% of the total suspended sediment load, were selected for study. The results of canonical discriminant analysis indicated that extreme erosion events are characterized by high maximum flood-suspended sediment concentrations, high runoff coefficients, and high flood peak discharge, which could possibly be explained by the transport of deposited sediment within the stream bed during previous events or bank collapses.     

Sustained isocapnic hypoxia suppresses the perception of the magnitude of inspiratory resistive loads.

The sensation of increased respiratory resistance or effort is likely to be important for the initiation of alerting or arousal responses, particularly in sleep. Hypoxia, through its central nervous system-depressant effects, may decrease the perceived magnitude of respiratory loads. To examine this, we measured the effect of isocapnic hypoxia on the ability of 10 normal, awake males (mean age = 24.0 +/- 1.8 yr) to magnitude-scale five externally applied inspiratory resistive loads (mean values from 7.5 to 54.4 cmH(2)O. l(-1). s). Each subject scaled the loads during 37 min of isocapnic hypoxia (inspired O(2) fraction = 0.09, arterial O(2) saturation of approximately 80%) and during 37 min of normoxia, using the method of open magnitude numerical scaling. Results were normalized by modulus equalization to allow between-subject comparisons. With the use of peak inspiratory pressure (PIP) as the measure of load stimulus magnitude, the perception of load magnitude (Psi) increased linearly with load and, averaged for all loaded breaths, was significantly lower during hypoxia than during normoxia (20.1 +/- 0.9 and 23.9 +/- 1.3 arbitrary units, respectively; P = 0. 048). Psi declined with time during hypoxia (P = 0.007) but not during normoxia (P = 0.361). Our result is remarkable because PIP was higher at all times during hypoxia than during normoxia, and previous studies have shown that an elevation in PIP results in increased Psi. We conclude that sustained isocapnic hypoxia causes a progressive suppression of the perception of the magnitude of inspiratory resistive loads in normal subjects and could, therefore, impair alerting or arousal responses to respiratory loading.     

Microbial load of drinking water reservoir tributaries during extreme rainfall and runoff

Hygienic and microbiological examinations of watercourses are usually not carried out during heavy rainfall and runoff events. After rainfall or snowmelt, there are often massive increases in turbidity in flooding creeks in mountain ranges, which are frequently interpreted as an indication of microbial contamination. The aim of this study was to quantify the microbial loads of watercourses during such runoff events and to compare these loads with loads occurring during regular conditions. In a 14-month monitoring period we investigated the microbial loads of three tributaries of different drinking water reservoirs. A total of 99 water samples were taken under different runoff conditions and analyzed to determine physical, chemical, bacterial, and parasitic parameters. Thirty-two water samples were considered event samples during nine measuring series. The criteria for events, based on duration and intensity of precipitation, water depth gauge measurements, and dynamics, had been fixed before the investigation for each creek individually. Of the physical and chemical parameters examined, only the turbidity, pH, and nitrate values differed clearly from the values obtained for regular samples. Most of the bacteriological parameters investigated (colony, Escherichia coli, coliform, fecal streptococcal, and Clostridium perfringens counts) increased considerably during extreme runoff events. If relevant sources of parasitic contamination occurred in catchment areas, the concentrations of Giardia and Cryptosporidium rose significantly during events. The results show that substantial shares of the total microbial loads in watercourses and in drinking water reservoirs result from rainfall and extreme runoff events. Consequently, regular samples are considered inadequate for representing the microbial contamination of watercourse systems. The procedures for raw water surveillance in the context of multiple-barrier protection and risk assessment ought to include sampling during extreme runoff situations.     

Allelic and Genotypic Composition of Ancestral Spanish and Colonial Californian Gene Pools of Avena Barbata: Evolutionary Implications

Spanish explorers and colonists inadvertently started a massive experiment in evolutionary genetics when they accidentally introduced Avena barbata to California from Spain during the seventeenth and eighteenth centuries. Assays of the Spanish and Californian gene pools of this species for 15 loci show that the present day Spanish gene pool, particularly that of Southwestern Spain, is identical or virtually identical to that of California for five loci and closely similar for nine loci. Despite their similar allelic and single-locus genotypic compositions, the present-day Spanish and Californian gene pools are differently structured on a multilocus genetic basis. Evolutionary implications of these results are discussed.     

Microbial Load of Drinking Water Reservoir Tributaries during Extreme Rainfall and Runoff

Hygienic and microbiological examinations of watercourses are usually not carried out during heavy rainfall and runoff events. After rainfall or snowmelt, there are often massive increases in turbidity in flooding creeks in mountain ranges, which are frequently interpreted as an indication of microbial contamination. The aim of this study was to quantify the microbial loads of watercourses during such runoff events and to compare these loads with loads occurring during regular conditions. In a 14-month monitoring period we investigated the microbial loads of three tributaries of different drinking water reservoirs. A total of 99 water samples were taken under different runoff conditions and analyzed to determine physical, chemical, bacterial, and parasitic parameters. Thirty-two water samples were considered event samples during nine measuring series. The criteria for events, based on duration and intensity of precipitation, water depth gauge measurements, and dynamics, had been fixed before the investigation for each creek individually. Of the physical and chemical parameters examined, only the turbidity, pH, and nitrate values differed clearly from the values obtained for regular samples. Most of the bacteriological parameters investigated (colony, Escherichia coli, coliform, fecal streptococcal, and Clostridium perfringens counts) increased considerably during extreme runoff events. If relevant sources of parasitic contamination occurred in catchment areas, the concentrations of Giardia and Cryptosporidium rose significantly during events. The results show that substantial shares of the total microbial loads in watercourses and in drinking water reservoirs result from rainfall and extreme runoff events. Consequently, regular samples are considered inadequate for representing the microbial contamination of watercourse systems. The procedures for raw water surveillance in the context of multiple-barrier protection and risk assessment ought to include sampling during extreme runoff situations.     

Seasonal benthic nitrogen cycling in a temperate shelf sea: the Celtic Sea

Spring runoff often comprises the majority of annual discharge and riverine phosphorus (P) export due to sustained high flow, and the magnitude of spring runoff can be a strong predictor of receiving water summer harmful algal bloom severity. Yet the loading of reactive forms of P during this time period remains poorly-characterized in time, space and geochemical partitioning. Here, we explore the hypothesis that riverine dissolved and suspended sediment P loads during spring runoff have a particularly high proportion of potentially reactive species due to unique hydrologic pathways and P association with iron (Fe).The concentration, distribution and temporal dynamics of dissolved P (DP), dissolved and colloidal Fe, and redox sensitive suspended sediment P (RSP) and Fe during spring runoff and summer storms were compared in forested and agricultural catchments of the same watershed. The dominant carrier of RSP was Fe (oxy)hydroxides across land cover and season, but Fe (oxy)hydroxide particles and colloids in agricultural catchments were strongly enriched in RSP and DP during spring runoff and summer storms, particularly at the onset of snowmelt. In 2014, 83% of DP and 74% of RSP were delivered to Missisquoi Bay during spring runoff. Suspended sediment was significantly more redox sensitive than typically input to limnological models, suggesting that the reactivity of this load may be systematically underestimated. Changes in the timing, provenance and severity of spring runoff associated with climate or land cover change will have dramatic impacts on total riverine P loads and their potential reactivity in receiving water ecosystems.     

Constructed identities and Iberia

The category of Iberian identity includes national identities within Spain, Portugal and Latin America. The case of Spain and Spanish national identity has been particularly neglected in academic literature, although this situation has been changing since the mid-1990s, in comparison with analyses of alternative national identities within the Spanish state. This is related the discrediting of Spanish nationalism during the Francoist dictatorship later democratic devolution which encouraged an analogous diversification in the study of national identities within Spain. Since the asymmetric of Spain, Spanish interpretations of nationhood have reflected the premise of the 1978 Constitution that the nation's unity is complemented and strengthened by its national and regional diversity. Variety within broad category of Iberian identities is augmented by the incidence of labour migration into Spain and Portugal and development of popular culture, this case music, in Latin America and specifically Colombia.     

Relationship between bronchopulmonary nematode larvae and relative abundances of Spanish ibex (Capra pyrenaica hispanica) from Castilla-La Mancha, Spain

The excretion of bronchopulmonary nematode infective larvae was evaluated in 160 faecal samples of Spanish ibex (Capra pyrenaica hispanica) collected from 13 populations in Castilla-La Mancha, south-central Spain in September 2003. Intensities and prevalences were compared with pasture availability, abundances of wild and domestic ungulates at both levels, i.e. for populations and for faeces in a two-step procedure. Protostrongylid larvae showed similar infection rates (mean intensity: 1.56+/-0.12, n=94; mean prevalence: 25.62+/-6.86%, n=160) to Dictyocaulus spp. (mean intensity: 1.03+/-0.11, n=48; mean prevalence: 30.00+/-7.11%, n=160). At the population level, positive correlations were found between the prevalences of both bronchopulmonary taxa. The prevalence in both groups, but not intensity, also correlated positively with Spanish ibex abundance indexes both for the populations and individual faeces. These findings suggest that: (i) parasite spreading across Spanish ibex populations in Castilla-La Mancha could respond to host density-dependent processes; and (ii) these populations may have similar exposition and/or susceptibility to both bronchopulmonary taxa resulting in similar host-parasite patterns, despite their different life cycles. Bronchopulmonary outputs in the Spanish ibex from Castilla-La Mancha seems not to represent a health risk for this endemic wild ungulate but may be useful in any health surveillance scheme for the increasing populations of Spanish ibex.