Search

AbstractIn this study, particulate matter (PM) variation has been analyzed to address the dearth of scientific research on air pollution in a coastal city from south India. Mean PM2.5 and PM10 concentrations were 61.6 ± 26.4 and 87.3 ± 35.4 μg/m3. The highest (lowest) seasonal concentration was observed during winter (monsoon). Increase in PM from September to February is attributed to low relative humidity, biomass burning in nearby paddy fields, and continental air mass from the east and north-easterly direction. The mean PM2.5/PM10 ratio was 0.71, with the seasonal ratio ranging between 0.64 (summer) and 0.76 (monsoon), indicating the dominance of anthropogenic PM fraction. PM exhibited typical characteristic of the urban region, i.e., a two-peak diurnal trend during all seasons except monsoon. PM10 (PM2.5) concentrations decreased by ∼7–24.2% (∼11–21%) on the weekends, with the highest reduction in winter seasons. Regarding correlation analysis among PM, CO, and ozone; a negative correlation between PM10 and O3 and a positive correlation between PM and CO was observed. Wind speed and PM10 showed a positive quadratic linear, whereas wind speed and PM2.5 showed a negative linear relationship. The primary sources of particulate matter in Kannur town are motor vehicle emissions, dust from construction work in surrounding zones, and nearby industrial units. [ABSTRACT FROM AUTHOR]

The continuously increasing demands of food, feed and various corn-derived products accelerate the concern about the corn production on environment. Nevertheless, few researches simultaneously address the issue from different perspectives of carbon, water and energy as well as their temporal variations. Herein, a systematic cradle-to-gate life cycle assessment of maize production was conducted with a case study in Shandong, China. Different midpoint and endpoint indices including 10-year average data from 2011 to 2020 and their temporal variations were investigated. The contribution analysis of different processes to these indices revealed that irrigation dominated the midpoint of water scarcity, whereas the sum of direct consumption, fertilizer and diesel production contributed more than 80% to all the other indices. The sensitivity analysis also illustrated that these environmental indices can be reduced by as high as 4% when the aforementioned inputs were individually decreased by 5%. The temporal variation of the global warming potential, aquatic eutrophication and fossil depletion demonstrated that all the three indices were decreased by about 25.0%–31.7% over the last decade. Further persistent efforts to enhance mechanized operation efficiency and explore green and efficient methods for fertilizer and diesel production were highlighted. Moreover, implementations of rational agricultural management such as scientific fertilization and water-efficient irrigation were suggested, in order to have an eco-friendly maize production system. [ABSTRACT FROM AUTHOR]

Satellite observations of precipitation have greatly improved our understanding of its temporal and spatial distribution. In view of the high spatiotemporal heterogeneity and severely skewed distribution characteristics of precipitation, it is necessary and of considerable application value to understand the ability of satellite-derived precipitation products (SPPs) to characterize the variations of precipitation in the time and space dimensions separately. However, to date, research concerning this is scarce. In this study, we explore the ability of 13 SPPs to characterize the temporal and spatial variations of precipitation based on observations from more than 2400 meteorological stations in Chinese mainland from 2001 to 2018. The results show that (1) SPPs tend to perform better in identifying the temporal than the spatial variation of precipitation. Most SPPs can reliably monitor the temporal and spatial variation of monthly and seasonal precipitation in Chinese mainland, although the identification of the spatial variation of daily precipitation involves larger uncertainty; (2) CMORPH-B, IMERG-F, 3B42, and MSWEP generally had better performance in identifying the temporal and spatial variations of precipitation, while PERSIANN and GSMaP-N performed poorly. However, no single SPP outperformed others in all scenarios; (3) with respect to monitoring the temporal variation of daily precipitation, SPPs performed better in southern China than in the north, with three-quarters and half of median KGE values above 0.5 In comparison, no significant spatial difference was observed in their ability to monitor the spatial variation of daily precipitation; and (4) SPPs had large uncertainties in capturing the temporal and spatial variations of precipitation in winter, while they performed best in identifying the temporal and spatial variations of daily precipitation in summer. The results of this paper provide an important reference for data users needing to select suitable SPPs and for satellite developers desiring to further improve data quality. [ABSTRACT FROM AUTHOR]

Phenotypic plasticity is the ability of individual organisms to alter their phenotypes to persist in response to internal states or changing environments. Like many other organisms, the specialist predatory mite, Phytoseiulus persimilis Athias-Henriot (Acari: Phytoseiidae), showed plasticity in developmental time and size at maturity under food stress. In this study, we investigated the influence of food stress with different temporal feeding variations on the developmental time, prey consumption, and size at maturity of P. persimilis. Individuals of P. persimilis were reared under laboratory conditions using enclosed rearing cells. The predators responded to temporal feeding variations but not to prey densities regarding their developmental time and size at maturity, and the response was sex-specific (i.e. significant only in females). Diet restrictions at different life stages of P. persimilis can induce plasticity in their life history traits. Future studies can investigate whether diet restrictions encountered by individuals at different life stages influence their reproduction and lifespan. [ABSTRACT FROM AUTHOR]

To investigate the effect of submerged macrophytes on heterotrophic bacterioplankton communities in response to nutrient enrichment, we simulated mesocosms to test two factors, namely, the presence of Ceratophyllum demersum (L.) and the level of nutrients (slight and medium nutrient enrichment) under four possible system combinations for a duration of more than 3 months. The results show that C. demersum can affect the temporal dynamics of heterotrophic bacterioplankton density (HBD) and cause it to decrease. However, the effect of C. demersum on HBD was more pronounced under medium nutrient enrichment. The mean values of HBD in the treatment and control systems under slight nutrient enrichment were 1.30 × 105 cells mL−1 and 1.34 × 105 cells mL−1, respectively; whereas for medium nutrient enrichment, they were 1.78 × 105 cells mL−1 and 2.65 × 105 cells mL−1, respectively. The total nitrogen (TN) and total phosphorus (TP) concentrations were maintained throughout the experiment, and no significant differences were observed in the pH value, chlorophyll a (Chl. a) concentrations or dissolved organic carbon (DOC) levels between the systems with and without macrophytes, regardless of the nutrient level. Furthermore, linear mixed models revealed that environmental variables had a limited impact on HBD and that C. demersum had no significant direct effect on the environmental variables in the systems. A likely explanation is higher predation on bacterioplankton in the mesocosms, although allelopathic effects exerted by C. demersum cannot be excluded. [ABSTRACT FROM AUTHOR]

Macroinvertebrate communities in running waters are commonly used as bioindicators of fine sediment pollution, but few studies evaluate impacts across multiple years. We used a 5-year dataset from 46 rivers in Southland, New Zealand to investigate the consistency of the relationship between deposited fine sediment and stream macroinvertebrates across three categories of agricultural land-use intensity (low, medium, and high). We also compared the performance of four widely used invertebrate stream health metrics and their recently developed sediment-specific counterparts. Linear and non-linear regressions were fitted and effect sizes were interpreted to identify biologically meaningful relationships (r2 ≥ 0.1). Sites within medium-intensity catchments showed the greatest number of such relationships (29 of 40 cases), compared to low- (8) or high-intensity catchments (23). Invertebrate metrics responded more frequently, and mostly negatively, to increasing sediment in medium- and high-intensity catchments. Overall, sediment-specific metrics performed better than their widely used counterparts. Our findings show that land-use intensity influences the multi-year dynamics of deposited fine sediment and the corresponding stream invertebrate responses. These temporal dynamics can be substantial and should be considered in future stream biomonitoring efforts. [ABSTRACT FROM AUTHOR]

South Africa is the dominant continental source region of CO2 fossil fuel emissions. This is a result of the strong dependence of its economy on fossil fuels. However, the observations of atmospheric CO2 in South Africa are inadequate. The country has the Global Atmospheric Watch (GAW) Cape Point station as the only site with long-term ambient CO2 monitoring record. In this study, satellite data retrieved from the Tropospheric Emission Spectrometer (TES) instrument on board the Aura satellite from Dec 2004 to Dec 2009 is used for the first time to quantify the spatial distribution of CO2 over South Africa, as well as to determine its annual variability at selected sites. The study found that the surface CO2 foot print in South Africa resembles the industrial CO2 emission sources spatial distribution, particularly during the summer and autumn. In winter and spring seasons the surface CO2 foot prints are spatially expanded as a result of contributions of emissions from biomass and domestic fossil fuel combustion. The surface levels of CO2 at the study areas have been increasing during the period of the analysis. [ABSTRACT FROM AUTHOR]

Worldwide there is an increasing awareness of the potential risks that pasture grazing systems pose to freshwater. Excess nutrient levels, predominately nitrate ( N O 3 − ), result in reduced water quality. This study focused on further understanding how the presence or absence of perennial ryegrass (Lolium perenne L) and bovine urine (BU) influenced both the N O 3 − isotopic signature and the amount of N O 3 − leached. Plant presence resulted in lower N O 3 − -N concentrations and reduced N O 3 − -N leaching over the nine-month trial period. A total of 15, 79 and 234 kg/N/ha was leached from the 0, 300 and 700 kg/N/ha BU treatments, respectively. Drainage volumes varied with season and plant treatments (plants 420±47 mm, no-plants 539±29 mm total drainage). The isotope values were found to be most influenced by plant treatment in the absence of BU. Under BU these isotopic signatures varied temporally due to denitrification and were influenced by plant treatment in the absence of BU, but this does not confound interpretation of isotope data when BU is applied. Nitrate isotopes show potential for identifying N O 3 − sources and soil processes forming and removing N O 3 − . Further datasets are required to improve our understanding of BU rate effects on the temporal dynamics. [ABSTRACT FROM AUTHOR]

The change in soil microbial biomass (SMB) content and its direct links to soil organic matter (SOM) and environmental factors are not well understood for high-elevation regions. Therefore, this research investigated the temporal variation of SMB and its relationship with SOM and environmental factors in an alpine meadow site on the Qinghai-Tibetan Plateau. The soil organic carbon (SOC) and total nitrogen (TN) contents in alpine meadows showed monthly and seasonal variations and were higher in colder months, and the soil C/N ratio was higher in winter and in autumn than it was in the other seasons (P < 0.05). In addition, the changes in the SMB C and SMB N contents were notable at monthly and seasonal scales, whereas the SMB C and SMB N contents were higher in the winter and spring than they were in the other seasons (P < 0.05); the ratio of SMB C/SOC was higher in spring than it was in the other seasons; the ratio of the SMB N/TN content was higher in cold or cool months than it was in the other months; and the ratio of the SMB C/SMB N was highest in August (P < 0.05). Moreover, the SMB C and SMB N contents were significantly positively correlated to the SOC and TN contents (P < 0.01), and the SMB content was also significantly positively correlated to soil water content and air temperature (P < 0.05), or to soil bulk density and soil pH (P < 0.05). The results suggested that the change in the SMB in the alpine meadows was highly regulated by the SOC and TN and by monthly and seasonal changes in the soil bulk density, the soil pH, soil moisture, and air temperatures. [ABSTRACT FROM AUTHOR]

We examined the temporal variation of heavy metals in different sexes of three brackish water shrimp species with emphasis on the relationship between Fulton's K condition indices and metal pollution index (MPI). Zn was the most abundant metal followed by Sn, though levels were below the admissible limits (irrespective of gender). Temporal variation of Zn and Pb was significant (p < 0.01). Drier weather conditions influenced Pb accumulation. Temporal variation of Sn was insignificant (p > 0.05), but temporal variation of Hg was significant only in Penaeus monodon (p < 0.0001). However, the relationship between temporal variation of the above-mentioned metals and gender was insignificant except in Penaeus semisulcatus for Pb (p < 0.02) and Sn (p < 0.04) despite no consistent higher bioaccumulation pattern by one particular sex. There were no significant negative correlations between the Fulton's K condition indices and MPI values in the different sexes. MPI values between the two sexes were insignificant. Any differences in the MPI values between the three species were insignificant. Only Penaeus semisulcatus exhibited significant differences (p < 0.022) in Fulton's K condition indices in relation to gender. Fulton's K condition indices are unreliable indicators of metal-induced stress levels in shrimps. [ABSTRACT FROM AUTHOR]

Global loss of wetlands has increased significantly in recent years. As a result, many wetlands have experienced changes in biotic communities, including birds. We compare the temporal variation in bird communities and the effects of land-use change on the structure and function of avian assemblages in the Lower Delta of the Paraná River (Argentina). We detected 28 families and 80 species of birds, with the highest richness, diversity and evenness in spring and summer because of the arrival of migratory species. Bird diversity, richness and evenness were significantly higher in secondary forests than in poplar plantations and cattle-grazing grasslands. Bird assemblages were related to structural differences of the habitat types and only generalist forest species were found in active plantations. Secondary forests exhibited species typical of the original riparian forest, practically extinct in the region. We speculate that abundance of guilds among habitat types is related to food supply and to plant composition. Our study shows for the first time how the conversion of wetlands into a Salicaceae plantation impacts on birds, particularly on wetland species. This demonstrates the need to implement management strategies to maintain a mosaic including secondary forests and freshwater marshes in order to conserve these species. [ABSTRACT FROM AUTHOR]

Economic development and population growth in Tehran has increased demand for goods movement and road transportation. This trend has increased mobile source emissions and citizens' exposure, imposing severe health risks. We used the framework of Land-Use Regression models to quantify the effect of real-time traffic, within buffer distance, on hourly exposure of CO, NO2, and PM2.5. Effect of residential, industrial, and governmental land-use in addition to the effect of pollution sources, such as construction sites and airport were assessed on air pollution. Meteorological variables were also employed to adjust between day variations. R-squared of the models were 38, 27, and 38% for CO, NO2, and PM2.5, respectively. Time-activity diaries can be combined with the developed LUR models to provide detailed exposure estimation for epidemiological studies. Furthermore, capability of simulating short-term effect of different traffic scenarios enables city administrations to evaluate policies aiming to diminish pollution levels, prior to applying them. [ABSTRACT FROM AUTHOR]

There is increasing interest in participation by volunteers in data collection for marine ecosystems. Here we evaluate the contribution that citizen scientists can make to documenting marine biodiversity through underwater photography of targeted taxa. In a series of 13, 24-hr censuses of sea slugs, at intervals of three months from December 2013 to December 2016, volunteers recorded similar species richness (89%) to scientists at Port Stephens, NSW, Australia. Volunteer numbers only partially (24.9% of variation) explained the relative performance of volunteers against scientists, or the number of species found by volunteers (20.5%). Species richness in censuses was similar (97%) to estimates obtained during four-week lead-up periods. The programme provided novel information on diversity and seasonality of sea slugs, revealing strong seasonal patterns for chromodorid nudibranchs, and cyclical temporal change at the assemblage level. The programme inspired many of the participants to take part in multiple events, generated educational material, and led to the extension of the programme to other locations. The potential benefits of programmes such as this go beyond the generation of data to address specific research questions and, combined with extension activities, can help to deliver and reinforce messages about the importance of marine ecosystem health. [ABSTRACT FROM AUTHOR]

Bursa is one of the largest cities of Turkey and it hosts 17 organized industrial zones. Parallel to the increase in population, rapidly growing energy consumption, and increased numbers of transport vehicles have impacts on the air quality of the city. In this study, regularly calibrated automatic samplers were employed to get the levels of air pollution in Bursa. The concentrations of CH4 and N-CH4 as well as the major air pollutants including PM10, PM2.5, NO, NO2, NOx, SO2, CO, and O3, were determined for 2016 and 2017 calendar years. Their levels were 1641.62 ± 718.25, 33.11 ± 5.45, 42.10 ± 10.09, 26.41 ± 9.01, 19.47 ± 16.51, 46.73 ± 16.56, 66.23 ± 32.265, 7.60 ± 3.43, 659.397 ± 192.73, and 51.92 ± 25.63 µg/m3 for 2016, respectively. Except for O3, seasonal concentrations were higher in winter and autumn for both years. O3, CO, and SO2 had never exceeded the limit values specified in the regulations yet PM10, PM2.5, and NO2 had violated the limits in some days. The ratios of CO/NOx, SO2/NOx, and PM2.5/PM10 were examined to characterize the emission sources. Generally, domestic and industrial emissions were dominated in the fall and winter seasons, yet traffic emissions were effective in spring and summer seasons. As a result of the correlation process between Ox and NOx, it was concluded that the most important source of Ox concentrations in winter was NOx and O3 was in summer. [ABSTRACT FROM AUTHOR]

The parasite community of the ray Rhinoptera steindachneri from Acapulco Bay was examined and quantified; analyses were based on the sex of the host and the date of sampling. A total of 171 specimens of R. steindachneri were examined during July-August of 2010, and May and July of 2012. Twenty-one species of parasites were found: three species of Monogenea; eight adult and one larval species of Cestoda; one larval species of Nematoda; five species of Copepoda; two species of Isopoda; and one species of Hirudinea. Cestodes had the greatest species richness (43% of the total species), followed by the copepods (24%). Two species of cestode, Glyphobothrium sp. and Rhinebothrium sp., were collected only from adult rays. At the component community level, species richness showed statistically significant variation between 13 and 16 species, which is similar to previous reports for other species of rays. The parasite component communities and infracommunities of R. steindachneri exhibited similar patterns: high species number and low numerical dominance by a particular species of parasite. The differences of body size of male vs. female rays, and a change in diet and feeding behaviour with the age of R. steindachneri, are likely important factors in the structuring of their parasite communities. [ABSTRACT FROM AUTHOR]

Hydrothermal precipitates and hydrothermal alteration products could record important information about temporal variations of seafloor hydrothermal systems. Geochemistry, mineralogy, and microscopic features of three pumice samples (T3-1, T3-2, and T3-3) near the Iheya North hydrothermal field were analyzed in this article. The results show that T3-3 sample has undergone at least two-stage influences by hydrothermal fluids. In the first stage, pure amorphous silica from hydrothermal fluid precipitated in the vesicles of all three T3 samples as a result of conductive cooling and fluid-seawater mixing. The precipitation temperatures according to oxygen isotope thermometer are approximately 13-21°C. In the second stage, T3-3 pumice underwent low-temperature hydrothermal alteration, during which the amorphous silica precipitates were redissolved, together resulting in losses of FeO and SiO2 and gains of MgO, Pb, Zn, and Cu. Furthermore, ferruginous filamentous silica, which might be related to activities of Fe-oxidizing bacteria, was formed in the altered pumice. The transformation from pure amorphous silica precipitation to redissolution of the silica in T3-3 pumice might indicate a rise of temperature and/or decrease in silica concentrations in hydrothermal fluids, implying a changing hydrothermal environment. [ABSTRACT FROM AUTHOR]

The temporal variation in composition and abundance of the macro-epifauna associated with seaweeds (Ulva lactuca, Cladophora sp., Gracilariopsis longissima and Gracilaria bursa-pastoris) and seagrass (Cymodocea nodosa) was investigated at Menzel Jemil station in the Bizerte lagoon. Twelve replicate samples (25 x 25 cm frame) were collected monthly from October 2009 to September 2010. Sampling data yielded 21,575 invertebrate specimens from floating seaweeds and the seagrass, belonging to 40 taxa, of which 18 species were arthropods, 13 molluscs, three echinoderms, three fishes, two polychaetes and one cnidarian. Crustaceans were the most dominant and the most speciesrich group and Idotea balthica basteri the most abundant species, accounting for 28.94% of the total abundance. Minimum (9.25 ± 5.56 species) and maximum (19.75 ± 3.2 species) values of mean species richness were observed in December and June, respectively. Species richness and density of macro-epifauna showed similar trends to plant biomass and the highest values of both indices coincided with periods of maximal plant biomass. Mean values of Shannon's index H' and evenness J' were low, ranging from 0.34 ± 0.02 bit to 1.08 ± 0.06 bit and from 0.23 ± 0.03 to 0.52 ± 0.07, respectively. The high dominance of herbivores and detritivores highlighted the substantial role played by macrophytes as food source for associated macro-epifauna species. Multivariate analyses also indicated significant seasonal differences for the macro-epifauna assemblage and revealed significant relationships with environmental variables. According to the canonical correspondence analysis, concentrations of phosphates and nitrites and temperature were the variables that explained the variation of the macro-epifauna abundance in the Bizerte lagoon. [ABSTRACT FROM AUTHOR]

Population dynamics is a branch of ecology that studies temporal changes in the abundance of a population of organisms over time. This paper presents a study of the factors influencing population abundance of the acanthocephalanNeoechinorhynchus brentnickoliinDormitator latifrons, the Pacific fat sleeper, from Tres Palos Lagoon. Fish were sampled from February 2012 to February 2013. A total of 688 adult fish were examined. The mean total length of fish varied significantly from 16.10 ± 1.93 cm (September 2012) to 20.78 ± 3.82 cm (August 2012). ‘Prevalence of acanthocephalans exceeded 90% in all months, and mature individuals were present year round, indicating that recruitment of helminths occurred throughout the year. Mean abundance ranged from 32.3 (July 2012) to 89.3 helminths per fish (March 2012) and was significantly lower in the rainy season. The body size of fish was the best predictor of acanthocephalan abundance in every month; larger fish harbored more acanthocephalans than smaller ones. Although parasite loads were high in some months (up to 500 acanthocephalans in one fish), obvious damage to the health of fish was not evident. [ABSTRACT FROM PUBLISHER]

Setting: We developed an algorithm to assess recorded cough episodes and differentiate them from similar, non-cough sounds.Objective: To measure cough episodes in healthy young adults, cigarette smokers and non-smokers over a 24-hour recording period, during the course of normal activity.Design:The study subjects were students, aged 20–40 years old. 24-hour sound recordings were conducted by a portable recorder. Analysis used an algorithm that was developed and tested in the study.Results: Seventy students were recruited. Recordings included 2628 cough episodes in 1704 h of recording. The cough detection algorithm successfully detected 88.5% of recorded cough episodes and 95.6% of non-cough sounds. There was a clear tendency for more coughs among smokers. Autumn was the season with the highest mean cough episodes per day (58.65), while summer had the lowest (14.19). There was a strong correlation between self-reported cough episodes and recorded coughs. Cough episodes were significantly more frequent between noon and midnight (p < 0.0001).Conclusion: There is a very large range in daily coughs among healthy young adults. During sleeping hours there are less cough episodes. In autumn and spring there are more cough episodes compared to summer and winter, probably secondary to environmental factors. In smokers, the coughing rate is relatively high. If the cough detection device will be able to discriminate between cough variants (i.e. healthy versus patient), and stringent validation will confirm sensitivity and specificity, valuable data from this device may ease the decision regarding medications, or any other changes in order to improve outcome. [ABSTRACT FROM PUBLISHER]

Linear habitats are capable of providing essential resources for small mammals within agroecosystems. We analyzed demographic parameters ofAkodon azaraein a linear habitat of central Argentina. We used capture-mark-recapture models to determine temporal variations in survival, recruitment and population growth rate. The effects of temperature, rainfall and vegetation cover as well as of population abundances on the mentioned parameters were assessed in a 10-year study. Survival and growth rate showed seasonal variation, which was greater than the interannual variability observed. Temperature affected only recruitment. Linear habitats would provide resources for long term survival and reproduction ofA. azarae. [ABSTRACT FROM PUBLISHER]

Understanding the relative impacts of harvesting across an area such as a marine park is vital if the goals of fisheries management are to be met. Given their accessibility, densities of targeted intertidal turbinids should be relatively simple to quantify; however, natural spatial and temporal variability in these populations has hampered this effort. This study aimed to quantify short-term population dynamics of Turbo militaris in relation to current zoning regulations and accessibility. While our results reflected the variability found by other studies, we also detected significantly lower densities at a headland where harvesting is known to occur, and found a trend towards denser aggregations at more remote locations. Importantly, we found that densities at some locations were so low that current fisheries bag limits may be ineffective for protecting populations at local scales. Comparisons between study sites suggest a combination of no-take zoning and inaccessibility may provide the most effective protection for this species. However, a greater understanding of the wider impacts of harvesting, and processes affecting recovery, are essential to ensure sustainable management of this fishery. [ABSTRACT FROM AUTHOR]

The reference-condition approach evaluates the ecological impact at a site of interest through comparisons to unimpacted sites of otherwise similar conditions. Reference conditions should ideally represent natural spatial and temporal variation of unimpacted systems, including infrequent disturbance events. This study examined the year-to-year variability of unimpacted benthic macroinvertebrate communities in the Terra Nova National Park, Newfoundland and Labrador, Canada. Sites were sampled annually in October from 2006 to 2011, a time series that included a 100 year flood event associated with Hurricane Igor. Invertebrate collections from a nearby urbanized area were compared to the natural temporal and spatial range of reference sites to determine the adequacy of this approach. Significant year-to-year changes in macroinvertebrate community composition were observed among unimpacted sites, particularly samples collected in the year of Hurricane Igor. These samples were characterized by a lower abundance, but had only minor differences in taxonomic richness. One year later, the benthic community composition showed signs of returning to pre-hurricane conditions. Despite significant temporal change, the variation associated with unimpacted communities was relatively small compared to differences observed at a site from a nearby urban area. These results suggest that reference conditions are clearly dynamic and need to be accounted for. However, at least in the case of invertebrate communities, the magnitude of change associated with anthropogenic impact can greatly exceed that associated with natural temporal variation. [ABSTRACT FROM AUTHOR]

In this study, we evaluate the temporal variation in extrafloral nectaries (EFNs) secretion in different ontogenic stages of Alibertia verrucosa (Rubiaceae) fruits in a Neotropical savanna. We observe greater nectar secretion rate in fruits of intermediate size compared with young or ripe fruit, indicating that they are possibly more protected by ants. In addition, the nectar secretion was higher at night, a pattern that could be associated with an increase of herbivore pressure and water stress during the daylight hours. In fact, due to the high temperature and low humidity during the day in savannas, most herbivores display strong nocturnal activity, and plants can avoid nectar secretion in this period. Our results indicate that A. verrucosa can change the ants' attraction according to EFN secretion during the ontogenic stages of the fruits, probably secreting more nectar when the biotic defense are more necessary for the protection of the fruits and the plant as a whole. [ABSTRACT FROM AUTHOR]

The evolution of flowering phenology is the result of a trade-off that balances many factors, including growth, reproductive capacity, and temporal overlap with pollinators. When there is large temporal variation in temperature, particularly in the onset of frost, the optimum flowering strategy will vary from year to year. In Duluth, MN, USA, the end of the growing season can vary by more than 30 days. In this study, we observed flowering phenology and pollinator abundance on 15 genotypes of Solidago altissima in Duluth, MN. We predicted that temporal variation in temperature would lead to a range of flowering strategies in the S. altissima population; some genotypes flower early and in synchrony, some 'hedge their bets' by flowering over a range of dates, and others have an intermediate strategy. Our results indicate that genotypes vary in mean flowering date and duration of flowering and, for the two observed years, pollinator abundance was highest for early-flowering genotypes. [ABSTRACT FROM AUTHOR]

The deteriorating air quality in eastern China including the Yangtze River Delta is attracting growing public concern. In this study, we measured the ambient PM10and fine PM2.5in the mega-city, Nanjing at four different times. The 24-h average PM2.5and PM10mass concentrations were 0.033–0.234 and 0.042–0.328 mg/m3, respectively. The daily PM10and PM2.5concentrations were 2.9 (2.7–3.2, at 95% confidence interval) and 4.2 (3.8–4.6) times the WHO air quality guidelines of 0.025 mg/m3for PM2.5and 0.050 mg/m3for PM10, respectively, which indicated serious air pollution in the city. There was no obvious weekend effect. The highest PM10pollution occurred in the wintertime, with higher PM2.5loadings in the winter and summer. PM2.5was correlated significantly with PM10and the average mass fraction of PM2.5in PM10was about 72.5%. This fraction varied during different sampling periods, with the lowest PM2.5fraction in the spring but minor differences among the other three seasons. [ABSTRACT FROM AUTHOR]

The body-size distributions and biomass estimates of Caenis (Ephemeroptera: Caenidae), Cloeon (Ephemeroptera: Baetidae), Coenagrionidae (Odonata), Micronecta (Hemiptera: Corixidae), Chironominae (Diptera: Chironomidae) and Orthocladiinae (Diptera: Chironomidae), the most common and abundant insect taxa associated with a submerged macrophyte Lagarosiphon ilicifolius in Lake Kariba, are presented. Caenis has a univoltine life cycle, whilst Cloeon, Coenagrionidae, Chironominae and Orthocladiinae have multivoltine life cycles. Growth and reproduction of Micronecta occurred all year round. The Coenagrionidae had the highest mean biomass, which was significantly greater than those of the other taxa. Caenis and Orthocladiinae were sensitive to variations in water temperature and dissolved oxygen (DO) concentration, their highest biomasses occurring when temperatures were low and DO concentrations high. The biomasses of Chironominae and Orthocladiinae increased with rising water levels, but that of Caenis decreased. Total insect biomass was minimally affected by variations in water physico-chemical variables. The study suggests that water temperature, water level and DO concentration do have an effect on the biomasses of some insect taxa associated with Lagarosiphon in Lake Kariba. Mixing processes during de-stratification also affect the abundance and biomass of the insect taxa. [ABSTRACT FROM PUBLISHER]

Temporal variation in allele frequencies in a natural population of wild Vigna unguiculata was studied by making monthly collections of seeds over a two-year period. Using starch gel electrophoresis, four out of seven loci analysed were shown to be polymorphic (Enp, Fdh, Fle3 and Pgd2 ). These four loci showed significant variation in allele frequencies over time. Changes in population structure over time were analysed using F-statistic estimators. Although heterogeneity was evident between loci, the analysis showed significant differentiation among months within a year for all polymorphic loci. Fixation indexes were all positive and statistically different from zero, highlighting a significant departure from random mating. Using analysis of variance (ANOVA), the pattern of inbreeding (f) showed significant changes over time (season); among the polymorphic loci, Enp most strongly contributed to this significance. Significant correlations were found between allele frequencies at different loci. The monthly average gene diversity (He) and allele frequencies at the Enp locus were found to be significantly correlated with weather conditions (temperature and rainfall distribution). These allele frequency deviations over time can be attributed to changes in pollinator behaviour, and frequent genetic bottlenecks that are associated with changes in environmental conditions. [ABSTRACT FROM AUTHOR]

The relationships between the spatial and temporal variations in the abundance of the shrimp Nematopalaemon schmitti and water temperature, salinity, and texture and organic-matter content of the sediment, were analysed in Ubatumirim, Ubatuba and Mar Virado bays on the northern coast of São Paulo, Brazil. Sampling was carried out monthly, from January 1998 through December 1999, from a shrimp boat equipped with double-rig nets, along six transects in each bay. In total, 2 116 specimens of N. schmitti were caught. Their distribution differed among bays, transects and seasons (ANOVA, p < 0.05). Highest total abundance was found in areas of high organic matter content, in substrate composed mainly of very fine sand and silt and clay, and during winter and autumn. Although multiple regression analysis showed no significant relationship (p > 0.05), observations suggest that water temperature, sediment texture, organic-matter content, and the presence of biodetritus and plant fragments, provided favourable environmental conditions for the establishment of N. schmitti in the region. [ABSTRACT FROM AUTHOR]

The spatio-temporal variations of reference crop evapotranspiration (ETref) reflect the combined effects of meteorological variables, primarily wind speed, relative humidity, net radiation and air temperature. This study investigated the spatial distribution and temporal trends of ETref (calculated by the FAO-56 Penman-Monteith equation), pan evaporation (Epan) and pan coefficient (Kp) in a 140 × 103 km2 semi-humid to semi-arid area in China. The results show that: (i) although the spatial distributions of ETref and Epan are roughly similar and their spatial correlation is high over the growing season, Kp varied considerably in space due to high humidity in the east of the region and low humidity in the southwest; (ii) the monthly variations of ETref and Epan are similar to that of net radiation and opposite to that of relative humidity, while the monthly variation of Kp is similar to that of relative humidity and opposite to that of wind speed, and the long-term trend is slightly increasing for ETref and Epan, while significantly (10% significance level) increasing for Kp; and (iii) generally, the time series of ETref and Epan from 1951 to 2001 could be divided into three phases due to variations of meteorological variables. Citation Liang, L.-Q., Li, L.-J. & Liu, Q. (2011) Spatio-temporal variations of reference crop evapotranspiration and pan evaporation in the West Songnen Plain of China. Hydrol. Sci. J. 56(7), 1300–1313. [ABSTRACT FROM AUTHOR]

Temporal and seasonal variability of As concentrations in groundwater were evaluated in As-affected areas of Matlab, southeastern Bangladesh. Groundwater samples from 61 randomly selected tubewells were analyzed for As concentrations over a period of three years and four months (from July 2002 to November 2005) and monitored seasonally (three times a year). The mean As concentrations in the sampled tubewells decreased from 153 to 123 μg/L during July 2002 to November 2005. Such changes were pronounced in tubewells with As concentration >50 μg/L than those with As concentrations <50 μg/L. Similarly, individual wells revealed temporal variability, for example some wells indicated a decreasing trend, while some other wells indicated stable As concentration during the monitoring period. The mean As concentrations were significantly higher in Matlab North compared with Matlab South. The spatial variations in the mean As concentrations may be due to the differences in local geological conditions and groundwater flow patterns. The variations in mean As concentrations were also observed in shallow (<40 m) and deep (>40 m) wells. However, to adequately evaluate temporal and seasonal variability of As concentration, it is imperative to monitor As concentrations in tubewells over a longer period of time. Such long-term monitoring will provide important information for the assessment of human health risk and the sustainability of safe drinking water supplies. [ABSTRACT FROM AUTHOR]

The genetic structure of arrival cohorts of European eels in the continental basin of Adour, France, was analysed. A regular sampling was carried out during three successive seasons of migration to ensure a representative sampling of complete recruitment in the estuary. Genetic variability within this sample was evaluated by analysis of highly polymorphic microsatellite markers. A high level of polymorphism was highlighted but a lack of genetic differentiation was observed between cohorts collected during the three successive seasonal migrations. [ABSTRACT FROM AUTHOR]

Polychlorinated biphenyls (PCBs) were measured in the sediments of the Donggang River Watershed, one of the most polluted bodies of water in southern Taiwan. Field data showed that detectable concentrations of 121 PCB congeners were found and total PCBs were measured in 32 out of 33 samples, and 98 congeners were detected. The total concentrations of PCBs in the sediment ranged from 25.5-63.5 ngg-1 dw with a geometric mean ± standard deviation of 4.00 ± 1.73 ngg-1 dw, with one sample below the detection limit. The highest concentration (20.79 ngg-1 dw) was found at the most downstream sampling site near the head of the estuary, while average levels were highest at the tributary sampling site, ranging from 8.81-019.4 ngg-1 dw. In general, the average concentrations in the tributary sampling sites were higher than those in the main stem sampling sites, which were 24.02 ± 10.15 and 19.97 ± 8.9 ngg-1 dw, respectively. Among the 121 congeners, congener 1, 3, 22, 25, 33, 21, 53, 47, 41, 64, 71, 107, 136, 146, 158, 157, 200, 172, 189, 207, 205, 206, and 209 were all below the detection limit and were not found in any samples. Congeners 191, 85, and 26 were the most commonly detected, however, PCB 26, 12+13, and 52 were the most abundant congeners and contributed 11.5, 8.4, and 6.96% to the total PCBs, respectively. The results indicated that trace PCBs were still detectable in the sediment of the Donggang River and its tributaries. However, the concentrations were considerably lower than those found in other studies of nearby areas in Taiwan and around the world. [ABSTRACT FROM AUTHOR]

The objective of this study was to explore the correlation among urbanisation, climate change and human health. Temporal variation of the prevalence of communicable diseases and the meteorological parameters were analysed, and relations among communicable diseases, meteorological parameters and socio-economic statistical data are discussed based on correlation analysis and stepwise regression. The results showed that both socio-economic development and regional climate change have effects on the prevalence of communicable diseases. Prevalence of blood-borne diseases and sexually transmitted diseases in Xiamen significantly increased during the 1990s. On the other hand, the prevalence of respiratory infectious diseases and gastrointestinal infectious diseases showed a decreasing trend with economic development. Climate has changed in the past 50 years, and particularly so in the last 30 years. The prevalence of gastrointestinal infectious diseases is linked to variation of annual average temperature and relative humidity. Annual average temperature, maximum temperature, minimum temperature and precipitation could be important determinants of the prevalence of insect-borne diseases. [ABSTRACT FROM AUTHOR]

Soil is an important source of atmospheric carbon dioxide (CO2) and nitrous oxide (N2O). Studies of CO2 and N2O emissions from bare soil may explain annual changes in carbon (C) in soil organic matter (SOM) and help analyze N2O production from SOM. Therefore, CO2 and N2O emissions associated with the decomposition of SOM from bare soil are important factors for assessing the C budget and N2O emission in agricultural fields. We conducted a study over 7 years to assess the controlling factors of CO2 and N2O emissions from unplanted and unfertilized soil in Mikasa, Hokkaido, Japan. The CO2 flux increased in summer and there were significant positive correlations between the CO2 flux and soil temperature in the first 4 years. However, apparent relationships between CO2 flux and water-filled pore space, soil NH4 and NO3 concentrations were not observed. The slope of monthly CO2 emission against mean monthly temperature was positively correlated with monthly precipitation. These results suggest that the response of CO2 production to increases in soil temperature became more sensitive in wet soils. The average CO2 emission during the study period was 2.53 Mg C ha−1 year−1, and uncertainty in the annual CO2 emission was 24%. Annual precipitation explained the yearly variation (CO2 emission [Mg C ha−1 year−1] = 0.0021 × annual precipitation [mm year−1] −0.0499, R = 0.976, P < 0.001). Nitrous oxide flux increased from July to October and was positively correlated with CO2 flux. Based on the ratio of N2O-N : NO-N of fluxes, N2O appeared to be the main product of denitrification. The average N2O emission over the study period was 4.88 kg N ha−1 year−1, and uncertainty in the annual N2O emission was 58.5%. Strong relationships between the monthly emissions of CO2 and N2O suggest that N2O production by denitrification is strongly affected by SOM decomposition. Unlike CO2 emission, a relationship between N2O emission and precipitation was not observed because of the multiple pathways of nitrification and denitrification for N2O production induced by SOM decomposition. [ABSTRACT FROM AUTHOR]

Caloosahatchee River watershed and estuary has experienced a general decline in the water quality over the last several decades due to agriculture practices, development, and other human activities. The objective of this study is to assess the water quality condition in coastal Caloosahatchee River watershed by analyzing the data collected by South Florida Water Management District and Lee County. Results indicated that during 1995 to 2006, averaged annually, Lake Okeechobee released 1124 million m3 of freshwater into the Caloosahatchee River, whereas the average annual freshwater discharge out of the Caloosahatchee River was approximately 2277 million m3. Lake Okeechobee might have more impacts on the water quality condition of Caloosahatchee River in dry season than wet season. The loads ratios of Lake Okeechobee to those out of Caloosahatchee River were much higher in dry season than wet season for flow (72% to 36%), total phosphorus (63% to 20%), total nitrogen (72% to 41%), organic nitrogen (85% to 47%), and NH3 (78% to 39%). In the coastal watershed area where the urban area is concentrated, of the total 5453 water samples, 74% of them have dissolved oxygen concentration less than 5 mg L- 1, the United States Environmental Protection Agency and Florida Department of Environmental Protection water quality standard. Only in January is the average monthly dissolved oxygen concentration higher than 5 mg L- 1. [ABSTRACT FROM AUTHOR]

As tourists are sensitive to weather conditions and changes to the environments they visit, it is likely that climate change will affect coastal recreation in the future. To understand these impacts, it is first important to quantify how visitor numbers are associated with beach characteristics and weather patterns. Using the East Anglian coastline, UK, as a case study, information on the spatial distribution of visitors recorded from aircraft flights is combined with beach characteristic data in a Geographical Information System. In addition, surveys are undertaken at two beaches to assess temporal variations in visitation. The study finds a diverse range of characteristics are associated with visitor numbers. These findings are evaluated alongside the anticipated effects of climate change and management policies. Although it is predicted that warmer weather will increase visitor numbers overall, sea-level rise may reduce numbers at wide sandy beaches, which are currently most preferred by tourists. [ABSTRACT FROM AUTHOR]

The authors performed 3 experiments to measure temporal variation in airborne bacterial and fungal levels associated with the use of air conditioners (ACs), heaters, and humidifiers. The concentrations of bioaerosols that they measured inside vehicles and a seminar room prior to use of an AC were lower than or similar to those for outdoor air. In most cases, elevated concentrations occurred 5 to 15 minutes after the use of an automobile or household AC, and these concentrations decreased over time. For 3 of 5 cars, however, the bacterial concentrations did not vary significantly. For cars, the maximum bacterial concentration (2,550 CFU m-3) was 46 times higher than the in-vehicle background concentration (55 CFU m-3). Three fungi (Cladosporium, Penicillium, and Aspergillus) exhibited the highest concentrations for most sampling periods of the ACs and heater. The use of automobile heaters and household humidifiers could suppress in-vehicle and in-room microbial concentrations. [ABSTRACT FROM AUTHOR]

In this study, two fields of temperate Andisols from high-input and low-input (zero-input) management practices of an apple orchard were selected to assess microbial community dynamics based on environmental variables. Soils from an Ap horizon were sampled in five consecutive months from May to September and assessed for phospholipid fatty acids as a biomarker of soil microbial community, soil hardness, bulk density, porosity, pH, electrical conductivity (EC), organic carbon (C), available nitrogen (N) and phosphorus (P), and exchangeable cations as soil environmental variables. For all sample dates, total phospholipid fatty acids (PLFAs), total bacterial PLFAs, fungal PLFA, mycorrhizal PLFA, PLFA for actinomycetes, and earthworm were higher in low-input management than high-input management. Total PLFAs showed a high degree of seasonality, having August maxima and May minima. Significant effect on the relationships among soil environmental variables and microbiological attributes were observed. Soil management practices also showed a remarkable effect on the relationships among microbiological traits, indicating that some mechanism regulated soil microbial dynamics under two soil management practices. Comparatively higher correlations among the microbiological attributes were observed in low-input management than high-input management. Irrespective of soil management practices, bacterial and fungal lipid biomarkers were negatively correlated, suggesting that these subsets of fatty acids are contrasting components of the microbial biomass. Bulk density has negative influence on all soil microbial communities except fungi. On the other hand, linoleic acid and organic C were positively correlated, referring to the distribution of soil organic C implying an upper layer of soils. Microbial community composition and structure were greatly affected by sampling date and to a lesser extent by long-term management practice. In this study, both ecosystems were characterized by a very diverse microbial community. [ABSTRACT FROM AUTHOR]

To optimize regional crop rotation systems to mitigate soil organic carbon (SOC) depletion, monitoring the spatial and temporal variation of the SOC budget is of major importance. This study evaluated the influence of crop rotation and topography on the spatial and temporal variation of the SOC budget under cereal cropping in northern Kazakhstan using a geostatistical method, predicted equations of CO2 emission and Moderate Resolution Imaging Spectroradiometer satellite images. The study was carried out in large-scale upland fields (7,915 ha) located in Shortandy, Aqmorinskaya Oblast, from 2001 to 2005. Under the assumption that all crop residue was incorporated into the soil, average annual C input as plant residues in cereal and abandoned fields ranged from 1.0 to 1.6 Mg C ha−1 year−1, with higher values in wet years. Average annual CO2 emission in the cereal fields and the fallow fields ranged from 1.0 to 1.2 Mg C ha−1 year−1 and from 0.7 to 0.8 Mg C ha−1 year−1, respectively. In relation to topography, CO2 emission was higher on the north-facing slope than the south-facing slope, with the highest values on the higher plateau, and the average annual carbon budget ranged from –0.1 to 0.3 Mg C ha−1 year−1. It should be noted that all fallow fields consistently had a negative carbon budget. The 5-year carbon budget for different crop rotation systems ranged from –0.5 (fallow-based rotation) to 0.6 (wheat-based 5-year continuous cereal cropped) Mg C ha−1. These results have some uncertainly because of the low predictive ability of the regression; however, the results indicated that fallow-based and barley-based crop rotation systems were depletive and conversion of the wheat-fallow system to continuous wheat cropping would sequestrate 0.1–0.3 Mg ha−1 year−1 of carbon into the soil. [ABSTRACT FROM AUTHOR]

Numerous studies have documented a positive association between weekend hospitalization and mortality. Some researchers have argued that these associations are causal and arise from weekend reductions in hospital staffing. Others have suggested that the observed correlations reflect differences in the unobservable characteristics of weekend versus weekday patients. The existing literature has provided only limited evidence of the specific pathways through which weekend hospitalization might affect health outcomes. This article outlines the limitations of the existing research and highlights the need for in-depth condition-specific studies that acknowledge the potential threat posed by selection bias. [ABSTRACT FROM AUTHOR]

The temporal and spatial activity patterns of long-tailed bats (Chalinolobus tuberculatus) were assessed between January and July 1995 by automatic monitoring of echolocation calls, radiotelemetry and direct observation at hanging Rock, South Canterbury. Automatic bat detection units recorded 8728 bat passes and 933 feeding buzzes during 272 nights of sampling. in addition, five radio-tagged post-lactating female bats were each followed for an average of 13.0 ± 3.2 (SE) days. home range size averaged 471.4 ± 50.9 ha (95% median minimum convex polygons) but core areas of activity (50% of fixes) were 54.4 ± 5.4 ha (11.6 ± 3.1% of the home range size). Patterns of activity varied in relation to time of year, time of night, temperature, invertebrate activity and habitat. Between January and March, long-tailed bats consistently emerged from day roosts at sunset and flew throughout the night, with peaks of activity shortly after sunset and before sunrise. After the beginning of April, long-tailed bats no longer flew throughout the night, but they had one peak of activity between the first and third hour after sunset. Both automatic monitoring and radio-telemetry showed extensive use by long-tailed bats of river and riparian habitats. Radio-tagged bats avoided foraging over open farmland, and repeatedly returned to the same sites on consecutive nights. [ABSTRACT FROM AUTHOR]

Agricultural diversification in India is steadily accelerating towards high value crops and livestock activities to augment farm income. Some of the factors that influence the nature and pace of agricultural diversification from staple food to high value crops are technological change in crop production, improved rural infrastructure and diversification in food demand. The nature of agricultural diversification differs across regions due to wide heterogeneity in agro-climatic and socio-economic conditions. Generally, the pattern of agricultural diversification shows a shift from crop production to livestock production during the 1980s to 1990s. The livestock sub-sector across different regions has grown as a result of the mounting demand for livestock products, namely, milk, meat, eggs, etc. Diversification in favour of horticulture and livestock commodities is more pronounced in rainfed areas. The focus of this paper relates to diversification of food production and consumption in both rural and urban areas of India. With rising incomes, the patterns of diet normally change from a basic cereal-based diet to non-cereal items. Several recent studies have found evidence of this in India. Analyses of expenditure patterns of Indian households in urban and rural areas based on National Sample Survey data provide evidence that the income elasticity of demand for cereals is very low or zero for the population as whole, even though households at low income levels may still have a positive income elasticity of demand for cereals (Kumar, 2000). A varied diet is likely to include protein, fats and other non-cereal items such as fruits and vegetables. [ABSTRACT FROM AUTHOR]

The article examines the foraging behavior of macroinvertebrate in intertidal seagrass and sandflat population in New Zealand. The researchers used Carbon (C), Nitrogen (N) and Sulfur (S) isotopes to characterize the diet of the dominant Zostera capricorni found in intertidal and sandflat communities. Based on the results, the range of C and S values for Z. capricorni was, which highlighted the importance of accounting for spatial and temporal variability in primary producer isotopic signatures.

Information on the variability in supply of algal propagules is scarce, hindered by the difficulty in identifying propagules, but this variability may affect the distribution and abundance of algal assemblages. This study examined the small-scale (½ hourly to hourly) temporal variation in propagule supply of Chondrus verrucosus (Gigartinaceae, Rhodophyta) over a dense, isolated bed in south-eastern Japan in summer and winter of 1999. Either 0.5 litre scoop samples or 5 litre pump samples were collected ½ hourly to hourly over 13, 22.5, and 30 h on three occasions in summer (June & July) and 32 h on one occasion in winter (December). Sampling was conducted around either the new moon (two occasions in summer) or full moon (one occasion in both summer and winter) and incorporated full tidal sequences including daytime (summer) and nighttime (winter) low-low (LL) tides. Chondrus verrucosus was the only red alga with spores within the size range of 15-20 μm that was fertile in the study area and surrounds at the time of sampling facilitating identification of spores. Spores in scoop samples were settled onto Petri dishes and identified on the basis of cell shape, colour and size. Pump samples were filtered onto transparent membrane filters and identified using epifluorescence microscopy: C. verrucosus spores fluoresced bright yellow and were easily distinguished from other micro-organisms of similar size, which fluoresced red or green. Results showed that while propagules could be found in the water column at most times, propagule supply of C. verrucosus was greatest during the 1-2 h period following LL tides. Variability in propagule supply was less than in previous studies examining surface or offshore waters. Spore release is thought to be stimulated by either desiccation or salinity changes associated with periods of emersion at low tide followed by re-immersion on incoming tides. [ABSTRACT FROM AUTHOR]

Risk assessments often rely on deterministic models using long-term averages or "steady-state" values of input variables. Such models do not provide the information needed to estimate acute exposures. This study uses extreme value theory to examine the frequency and magnitude of daily pollutant concentrations in surface soils predicted at six U.S. locations. Concentrations are predicted using a deposition-leaching model and 50 years of historical precipitation data. A stochastic model also is used to generate 1000 years of precipitation data as modeling inputs for each location. The annual maximum concentrations at each site are fitted to a Gumbel type 1 distribution to estimate occurrence probability. For soluble pollutants, the predicted concentration varied substantially with precipitation, and the maximum daily concentrations exceeded annual averages by 4 to 8 times. Observed and synthetic precipitation data produced similar results at most study locations, though the synthetic data provided a slightly better fit to the Gumbel type I distribution. The precipitation model allows the generation of representative precipitation data that extend limited historical records. The extreme value analysis facilitates the evaluation of maximum pollutant concentrations, return periods, and other statistics that are important in evaluating acute exposures. [ABSTRACT FROM AUTHOR]

A previous paper in this Journal (Parker, 1992) detailed empirical research concerning the relative importance of the determinants of the capitalization rate for prime, CBD office investment property. Anecdotal comments that such relative importance may vary over time were also reported and are investigated here through further practitioner surveys. It is found that the identified determinants do vary over time but that some consistency is also evident, such that the proposition of a hierarchy of determinants may be feasible. [ABSTRACT FROM PUBLISHER]

Droughts can be distinguished by three vital characteristics—spatial coverage, intensity, and duration. The objective of the present study was to study the temporal and spatial variation of drought incidences by using the Standardized Precipitation Index (SPI) and Percent of Normal Precipitation (PNP) at multiple time scales; computed using monthly precipitation data (1960–2012) in the study area of 59 rain gauge stations. Drought climatology based on these drought indices (PNP and SPI) has been studied for finding out their suitability for drought monitoring over Krishna basin in Maharashtra. Study results indicate that at dry and wet conditions, the SPI performs better than PNP in monitoring drought at multiple time scales. However, SPI-1 fails to recognize drought conditions in pre-monsoon and post-monsoon months. The spatially interpolated droughts maps are prepared which displays the variation of drought severity across the study area. The ranking of stations has been done as per drought severity to identify severely drought prone areas. [ABSTRACT FROM PUBLISHER]

Daily and seasonal variations in the singing activity of the Turtle Dove and the detectability of territory-holding individuals were examined. The use of registrations of singing birds only was more reliable in identifying territories than registrations of all birds. Approximately 70% of known territories were detected during the two hours after sunrise, with less than 30% detected during the remainder of the day. Census work to determine density should therefore only be undertaken in the early morning. The relatively constant but low detection rate (10-20%) later than five hours after sunrise implies that the collection of data for calculation of indices of abundance can be made at this time. [ABSTRACT FROM AUTHOR]