temporal variation

The current paper synthesizes theory and data from the field of life history (LH) evolution to advance a new developmental theory of variation in human LH strategies. The theory posits that clusters of correlated LH traits (e.g., timing of puberty, age at sexual debut and first birth, parental investment strategies) lie on a slow-to-fast continuum; that harshness (externally caused levels of morbiditymortality) and unpredictability (spatial-temporal variation in harshness) are the most fundamental environmental influences on the evolution and development of LH strategies; and that these influences depend on population densities and related levels of intraspecific competition and resource scarcity, on age schedules of mortality, on the sensitivity of morbidity-mortality to the organism's resource-allocation decisions, and on the extent to which environmental fluctuations affect individuals versus populations over short versus long timescales. These interrelated factors operate at evolutionary and developmental levels and should be distinguished because they exert distinctive effects on LH traits and are hierarchically operative in terms of primacy of influence. Although converging lines of evidence support core assumptions of the theory, many questions remain unanswered. This review demonstrates the value of applying a multilevel evolutionary-developmental approach to the analysis of a central feature of human phenotypic variation: LH strategy.

Methods are usually classified as either "experimental" or "observational," a dichotomy that has governed social science research for centuries. By implication, this dichotomization precludes a consideration of experimental strategies in case study work. Yet, we argue that one gains purchase on the tasks of research design by integrating the criteria traditionally applied to experimental work to all research in the social sciences-including case study work, the focus of this article. Experimental research designs aim to achieve variation through time and across space while maintaining ceteris paribus assumptions, thus maximizing leverage into the fundamental problem of causal inference. We propose to capture these multiple criteria in a four-fold typology:

Respiration rate allows to differentiate between happy and sad excerpts which may be attributable to entrainment of respiration to the rhythm or the tempo rather than to emotions . Cardiovascular and respiratory responses during musical mood induction. Int. J. Psychophysiol. 61(1), 57-69]. In order to test for this hypothesis, this study intended to verify whether fast and slow rhythm, and/or tempo alone are sufficient to induce differential physiological effects. Psychophysiological responses (electrodermal responses, facial muscles activity, blood pressure, heart and respiration rate) were then measured in fifty young adults listening to fast/happy and slow/sad music, and to two control versions of these excerpts created by removing pitch variations (rhythmic version) and both pitch and temporal variations (beat-alone). The results indicate that happy and sad music are significantly differentiated (happy N sad) by diastolic blood pressure, electrodermal activity, and zygomatic activity, while the fast and slow rhythmic and tempo control versions did not elicit such differentiations. In contrast, respiration rate was faster with stimuli presented at fast tempi relative to slow stimuli in the beat-alone condition. It was thus demonstrated that the psychophysiological happy/sad distinction requires the tonal variations and cannot be explained solely by entrainment to tempo and rhythm. The tempo entrainment exists in the tempo alone condition but our results suggest this effect may disappear when embedded in music or with rhythm.

This paper sets out a philosophical approach to ichnological (trace fossil) analysis, which focuses on the interpretation of trace fossils as sedimentary structures rather than as paleontological entities per se. Using wide-ranging datasets and a large number of observations and interpretations, a "Process Ichnology" framework is proposed. This interpretive framework provides an improved means of estimating the presence and magnitude of various physical and chemical (i.e., physico-chemical) depositional stresses (e.g., water turbidity, sedimentation rates, substrate consistency, salinity, and oxygenation) in ancient sedimentary environments. Ichnological datasets that are considered include: 1) trace-fossil distributions; 2) ethological diversity and the range of diversity; 3) the significance of burrow linings; 4) trace-fossil size; and, 5) postdepositional compaction of trace fossils. From these data, higher-resolution estimates can be made for the determination of sedimentation rates, temporal variation in sedimentation rate, sediment consistency, and aspects of the bottom-and interstitial-water chemistries. Additionally, the character of depositional bypassing of sediment grains can be determined. The methodologies and interpretations herein are intended for use by non-ichnologists in a manner akin to the interpretation of physical sedimentary structures. However, the outlined framework is complementary to other methods of ichnological analysis, such as ichnofacies-or ichnofabric-analysis, and can be applied as such. Indeed, this method is a derivative of these and other earlier techniques, and should be employed where a systematic approach to obtaining high-resolution sedimentological interpretations is a required aspect of the study.

Temporal variation of PM 10 using 2-year data (January, 2007-December, 2008 of Delhi is presented. PM 10 varied from 42 to 200 lg m -3 over January to December, with an average 114.1 ± 81.1 lg m -3 . They are comparable with the data collected by Central Pollution Control Board (National Agency which monitors data over the entire country in India) and are lower than National Ambient Air Quality (NAAQ) standard during monsoon, close to NAAQ during summer but higher in winter. Among CO, NO 2 , SO 2 , rainfall, temperature, and wind speed, PM 10 shows good correlation with CO. Also, PM 10 , PM 2.5, and PM 1 levels on Deepawali days when fireworks were displayed are presented. In these festive days, PM 10 , PM 2.5 , and PM 1 levels were 723, 588, and 536 lg m -3 in 2007 and 501, 389, and 346 lg m -3 in 2008. PM 10 , PM 2.5 , and PM 1 levels in 2008 were 1.5 times lower than those in 2007 probably due to higher mixing height (446 m), temperature (23.8°C), and winds (0.36 ms -1 ).

This study deals with two range-extending brown algae from Tahitian coral reefs, Sargassum mangarevense and Turbinaria ornata; their alginate properties, mannitol and phenolic contents, antioxidant and antimicrobial activities were determined. Turbinaria ornata showed the richest alginate content with the highest extraction yield (19.2 ± 1.3% dw). Their alginates also exhibited the highest viscosity (50 ± 18 mPa.s), but the M:G ratios (mannuronic acid to glucuronic acid) of alginates (1.25–1.42) were similar in both species. Alginate yield displayed spatial variations, but no significant seasonal changes. The highest mannitol content was found in S. mangarevense (12.2 ± 2.1% dw) during the austral winter. With respect to other tropical Fucales, both algae exhibited also a high phenolic content (2.45–2.85% dw) with significant spatio-temporal variations. Furthermore, high antioxidant activity and activity against Staphylococcus aureus were also detected in extracts. According to these preliminary results, these two range-extending algae are of key interest in numerous industrial areas.

In this study, the performance of a combined subsurface vertical and horizontal flow constructed wetlands system, designed for rural domestic wastewaters treatment and with theoretical hydraulic retention time of 2 d and 3.6 d, respectively, was investigated. Several water quality parameters including pH, BOD 5 , COD, TSS, TKN and TP, and faecal bacteria's number in both raw and treated wastewaters were monitored during a macrophytes life cycle. At the same time, the growth of the rooted plants, reeds and cattails was investigated through the measurement of the height and leaves number. The average influent characteristics were as follows: pH (7.98 ± 0.27), BOD 5 (420 ± 144 mg/L), COD (1339 ± 352 mg/L), TSS (798 ± 302 mg/L), TKN (205 ± 70 mg/L), TP (30.7 ± 12.4 mg/L), faecal coliforms ([2.69 ± 4.14] × 10 7 CFU/100 mL) and faecal streptococci ([9.35 ± 1.81] × 10 6 CFU/100 mL). The main treatment performance results showed the following average removal rates: BOD 5 (93 ± 2%), COD (89 ± 3%), TSS (98 ± 1.5%), TKN (38 ± 19%), TP (72 ± 16%). The average bacterial reduction between the inlet and the outlet was of the order of 4 ± 1 logarithmic units for faecal coliforms and 3 ± 1 logarithmic units for faecal streptococci. Analysis of the results reveals a temporal variation in the system's performance depending on the primary treatment operation and on the macrophytes growth rate. Reeds and cattails start their life cycle at the beginning of the spring and continue their development during summer. During the autumn season, the plants reach their optimum growth rate, and after that, they enter the dormant phase. The quality of the treated wastewaters was evaluated according to Tunisian standards. The average effluent pH, BOD 5 , TSS and faecal bacteria were in agreement with the standards, but COD, nitrogen and phosphorus residual loads were still above the values required by the quality criteria.

In the Amazon basin, tropical rainforest is being slashed and burned at accelerated rates for annual crops over a couple of years, followed by forage grasses. Because of poor management, the productivity of established pastures declines in a few years so that grazing plots are abandoned and new areas are deforested. Previous studies in the region report higher bulk density in soils under pasture than in similar soils under forest. The objective of this study was to detect changes in the physical quality of the topsoil of nutrient-poor Typic Paleudults in the colonisation area of Guaviare, Colombian Amazonia, and analyse the effect of soil deterioration on pasture performance. Temporal variation of soil compaction under pasture was analysed by comparing natural forest taken as control and pasture plots of Brachiaria decumbens (Stapf) grouped into three age ranges (<3, 3-9, >9 years). Evidence of soil compaction through cattle trampling, after clearing the primary forest, included the formation of an Ap horizon with platy structure and dominant greyish or olive colours, reflecting impaired surface drainage, the increase of bulk density and penetration resistance, and the decrease of porosity and infiltration rate. From primary forest to pastures older than 9 years, bulk density of the 5-10 cm layer increase was 42% in fine-textured soils and 30% in coarse-textured soils. Penetration resistance ranged from 0.45 MPa under forest to 4.25 MPa in old pastures, with maximum values occurring at 3-12 cm depth in pastures older than 9 years. Average total soil porosity was 58-62% under forest and 46-49% under pasture. Basic infiltration dropped from 15 cm h −1 in the original forest conditions to less than 1 cm h −1 in old pastures. Crude protein content and dry matter yield of the forage grass steadily decreased over time. No clear relationship between declining protein content as a function of pasture age and changes in chemical soil properties was found, but there was a high negative correlation (r = −0.81) between protein content and bulk density, reflecting the effect of soil compaction on pasture performance. After about 9-10 years of use, established grass did no longer compete successfully with invading weeds and grazing plots were abandoned. As land is not yet a scarcity in this colonisation area, degraded pastures are seldom rehabilitated.

Editorial handling by Dr. R. Fuge a b s t r a c t Acid mine drainage represents a major source of water pollution in the Lousal area. The concentrations of trace metals and the rare earth elements (REE) in the host rocks, stream sediment, surface waters and acid mine drainage (AMD) associated with abandoned mine adits and tailings impoundments were determined, in order to fingerprint their sources and to understand their mobility and water-rock interaction. The results show that the Fe-SO 4 -rich acid waters vary substantially in composition both spatially and seasonally. These waters include very low pH (mostly in the range 1.9-3.0), extreme SO 4 concentrations (4635-20,070 mg L À1 SO 2À 4 ), high metal contents (Fe, Al, Cu, Zn and Mn) and very high REE contents. The trace metal concentrations decrease downstream from the discharge points either due to precipitation of neoformed phases or to dilution. The North-American shale composite (NASC)-normalized patterns corresponding to sediment from one stream (Corona stream) show a flat tendency or are slightly enriched in light-REE (LREE). The NASC-normalized patterns corresponding to acidic mine waters show enrichment in the middle REE (MREE) with respect to the LREE and heavy REE (HREE). Moreover, the REE concentrations in acidic mine waters are 2 or 3 orders of magnitude higher than those of the surface waters. Changes of REE concentrations and variation of Eu anomaly show two spatially distinct patterns: (a) pond and spring waters with higher REE concentrations (ranging from 375 to 2870 lg L À1 ), that records conspicuous negative Eu anomaly, and (b) seeps from tailings impoundments corresponding to lower REE concentrations than the first pattern (ranging from 350 to 1139 lg L À1 ) with typically negative Eu anomaly. The stream water samples collected from the impacted stream during the spring show a low pH (2.8-3.1) and contain high concentrations of Fe and trace elements (up to 61 mg L À1 ). Also, temporal variations of the REE concentrations were observed in the Corona waters. The results obtained show that the REE concentrations increase during the winter-spring transition. Stream waters draining the Lousal mine area show high REE concentrations, reaching a maximum value of about 2846 lg L À1 (spring). The MREE concentrations are usually enriched with respect to both the LREE and HREE. A decrease in REE concentrations and a pH increase from 3 to 6 was observed downstream of the confluence of a tributary stream.

The Dead Sea is a terminal lake of one of the largest hydrological systems in the Levant and may thus be viewed as a large rain gauge for the region. Variations of its level are indicative of the climate variations in the region. Here, we present the decadal-to centennialresolution Holocene lake-level curve of the Dead Sea. Then we determine the regional hydroclimatology that affected level variations. To achieve this goal we compare modern natural lake-level variations and instrumental rainfall records and quantify the hydrology relative to lake-level rise, fall, or stability. To quantify that relationship under natural conditions, rainfall data pre-dating the artificial Dead Sea level drop since the 1960s are used. In this respect, Jerusalem station offers the longest uninterrupted pre-1960s rainfall record and Jerusalem rains serve as an adequate proxy for the Dead Sea headwaters rainfall. Principal component analysis indicates that temporal variations of annual precipitation in all stations in Israel north of the current 200 mm yr Ϫ1 average isohyet during 1940 -1990 are largely synchronous and in phase (ϳ70% of the total variance explained by PC1). This station also represents well northern Jordan and the area all the way to Beirut, Lebanon, especially during extreme drought and wet spells. We (a) determine the modern, and propose the past regional hydrology and Eastern Mediterranean (EM) climatology that affected the severity and length of droughts/wet spells associated with multiyear episodes of Dead Sea level falls/rises and (b) determine that EM cyclone tracks were different in average number and latitude in wet and dry years in Jerusalem. The mean composite sea level pressure and 500-mb height anomalies indicate that the potential causes for wet and dry episodes span the entire EM and are rooted in the larger-scale northern hemisphere atmospheric circulation. We also identified remarkably close association (within radiocarbon resolution) between climatic changes in the Levant, reflected by level changes, and culture shifts in this region.

Seasonal change in beach morphology is traditionally ascribed to a variation in the incident wave energy level with calm conditions in summer resulting in wide beaches with pronounced subaerial berms and energetic conditions in winter causing narrow beaches with nearshore bar morphology. The coastline of Perth, Western Australia, is characterised by a large seasonal variation in the incident wave height and local beaches exhibit a distinct seasonal change in morphology. However, these morphological changes are better explained by a seasonal reversal in the littoral drift direction than by variations in the incident wave energy conditions. In summer, when northward sediment transport prevails due to sea breeze activity, beaches located south of coastal structures, headlands or rocky outcrops become wider due to the accumulation of sediment against the obstacle. These beaches will subsequently erode in winter during storms when the longshore sediment transport is toward the south. In contrast, beaches located north of obstacles will become narrower during summer and wider during winter. The usefulness of the dimensionless fall velocity (where Hb is the breaker height, ws is the sediment fall velocity and T is the wave period) as a predictor of presence/absence of bar morphology and beach type was investigated. It was found that Ω fluctuates around the threshold of bar formation (Ω≈1.5–2) over a variety of time scales (daily, weekly, and seasonally). These temporal variations in Ω in conjunction with the relatively low wave energy level that characterises the coast negates the development of beach and nearshore morphology that is in equilibrium with the hydrodynamic conditions. As a result, bar occurrence and beach type can not be readily predicted using Ω along the Perth coast.

This study deals with two range-extending brown algae from Tahitian coral reefs, Sargassum mangarevense and Turbinaria ornata; their alginate properties, mannitol and phenolic contents, antioxidant and antimicrobial activities were determined. Turbinaria ornata showed the richest alginate content with the highest extraction yield (19.2 ± 1.3% dw). Their alginates also exhibited the highest viscosity (50 ± 18 mPa.s), but the M:G ratios (mannuronic acid to glucuronic acid) of alginates (1.25–1.42) were similar in both species. Alginate yield displayed spatial variations, but no significant seasonal changes. The highest mannitol content was found in S. mangarevense (12.2 ± 2.1% dw) during the austral winter. With respect to other tropical Fucales, both algae exhibited also a high phenolic content (2.45–2.85% dw) with significant spatio-temporal variations. Furthermore, high antioxidant activity and activity against Staphylococcus aureus were also detected in extracts. According to these preliminary results, these two range-extending algae are of key interest in numerous industrial areas.

Importance of this paper: Methane and nitrous oxide concentrations in the atmosphere have been steadily increasing over the past several decades, intensive agricultural practices being one of the driving factors. Rice cultivation is an important source especially due to its large area under cultivation all over the world. Simultaneous emissions of these gases from rice make their mitigation efforts meaningful and justified. Mitigation options for both the gases should be carefully planned since minimizing one may lead to an increase in the other. It is thus necessary to assess their magnitude of emissions from rice, which may help in formulating joint mitigation practices without compromising crop and environmental quality and especially, to ensure that the cumulative radiative forcing of the two gases is minimum. The use of nitrification inhibitors may be useful as they may simultaneously mitigate both the gases and improve crop quality and protect the environment.

The adverse impact of groundwater contaminated with arsenic (As) on humans has been reported worldwide, particularly in Asian countries. In this study, we present an overview of the As crisis in the Southeast Asian region where groundwater is contaminated with naturally occurring As and where contamination has become more widespread in recent years. In this region more than 100 million people are estimated to be at risk from groundwater As contamination, and some 700,000 people are known so far to have been affected by As-related diseases. Despite investments exceeding many millions of dollars, there are still substantial knowledge gaps about the prevalence and impact of As, notably in its epidemiology, temporal variations, social factors, patient identification, treatment, etc. Arsenic-affected people in the affected regions also face serious social problems. Of major concern is the fact that many researchers from different countries have been conducting research in SE Asia region but with a lack of coordination, thus duplicating their work. There is an urgent need to coordinate these various studies to ensure better delivery of research outcomes. Further research is needed to improve field testing and monitoring of drinking water sources, and to develop new treatments for chronic As toxicity and new sources of safe drinking water.

What is more important: to provide citizens with more money or with more autonomy for their subjective well-being? In the current meta-analysis, the authors examined national levels of well-being on the basis of lack of psychological health, anxiety, and stress measures. Data are available for 63 countries, with a total sample of 420,599 individuals. Using a 3-level variance-known model, the authors found that individualism was a consistently better predictor than wealth, after controlling for measurement, sample, and temporal variations. Despite some emerging nonlinear trends and interactions between wealth and individualism, the overall pattern strongly suggests that greater individualism is consistently associated with more well-being. Wealth may influence well-being only via its effect on individualism. Implications of the findings for well-being research and applications are outlined.

This paper examines cross-national and temporal variations in the effect of personal unemployment on life satisfaction. To account for these variations we consider the social norm to work and national systems of unemployment benefits. Following the social psychological approach to social norms we differentiate between descriptive, societal injunctive and personal injunctive norms. We use the national unemployment rates as a proxy of the descriptive norm to work. The societal injunctive norm and the personal injunctive norm to work are conceptualized as society's vs. personal attitudes towards working for a living versus living off public funds, respectively.

Assessing the richness of invertebrate taxa to aid conservation and management requires a better understanding of the potential sources of error. Patterns of richness for heathland spiders at the species and family levels were compared across three sampling methods, four spatial scales, and monthly intervals (for 16 months). A total of 33 families and 130 species was collected: pitfall traps collected 94% of species, sweep net, 25%, and visual search, 41%. The sampling methods produced variable results. Pitfall trap and sweep net techniques identified significant, yet contrasting spatial differences in the number of families and species at one spatial scale. Pitfall trap data reflected strong temporal variation that influenced spatial patterns in richness (across one spatial scale for families and two for species). The use of broader temporal scales introduced a potential failure to detect significant differences in the richness of ground active spiders, and this risk varied spatially. The sweep net is not recommended for this habitat, although a method that targets the foliage is required for a more complete faunal assessment. Visual searches detected no significant patterns in richness, yet given its potential and increasing use for rapid biodiversity surveys, ways to improve sampling efficiency are suggested. J o u r n a l o f I n s e c t C o n s e

Daily total suspended particulate (TSP), particle size smaller than 100 mm and particle size smaller than 2.5 mm (PM 2.5 ) aerosol samples were collected at two sites in Shanghai in four seasons from September 2003 to January 2005. Concentrations of the water-soluble ions (SO 4 2À , NO 3 À , Cl À , F À , PO 4 3À , HCOO À , CH 3 COO À , NO 2 À , MSA, C 2 O 4 2À , NH 4 + + , K + , Cl À , NO 3 À , and SO 4 2À were mainly influenced by the anthropogenic emissions in land, meanwhile Cl À and SO 4 2À might be partly influenced by the sea. Na + , Mg 2+ , and Ca 2+ were derived from both inland crustal and marine sources. Chloride depletion was found especially in summer. The air pollution in Shanghai has proved to be under the influence of both the local emissions and the long-range transport from outside areas. r

It is more and more acknowledged that land-use/cover dynamic change has become a key subject urgently to be dealt with in the study of global environmental change. Supported by the Landsat TM digital images, spatial patterns and temporal variation of land-use change during 1995 –2000 are studied in the paper. According to the land-use dynamic degree model, supported by the 1km GRID data of land-use change and the comprehensive characters of physical, economic and social features, a dynamic regionalization of land-use change is designed to disclose the spatial pattern of land-use change processes. Generally speaking, in the traditional agricultural zones, e.g., Huang-Huai-Hai Plains, Yangtze River Delta and Sichuan Basin, the built-up and residential areas occupy a great proportion of arable land, and in the interlock area of farming and pasturing of northern China and the oases agricultural zones, the reclamation of arable land is conspicuously driven by changes of production conditions, economic benefits and climatic conditions. The implementation of “returning arable land into woodland or grassland” policies has won initial success in some areas, but it is too early to say that the trend of deforestation has been effectively reversed across China. In this paper, the division of dynamic regionalization of land-use change is designed, for the sake of revealing the temporal and spatial features of land-use change and laying the foundation for the study of regional scale land-use changes. Moreover, an integrated study, including studies of spatial pattern and temporal process of land-use change, is carried out in this paper, which is an interesting try on the comparative studies of spatial pattern on change process and the change process of spatial pattern of land-use change.

Sex ratios are a fundamental trait for species reproduction. In species with temperature-dependent sex determination (TSD), sex ratios are not necessarily even, which has important demographic consequences. We examined the sex ratio of juvenile pelagic stage loggerhead turtles Caretta caretta offshore Madeira Island, North Eastern Atlantic, using laparoscopy and histology. The overall sex ratio was 2:1 (F:M), significantly different from an even sex ratio. Although there was no apparent temporal variation, sex ratios among size classes were significantly different. The sex ratio of juveniles was compared with known sex ratios for the putative source rookery and found to be similar to the subadults' sex ratio, but significantly less female-biased than the hatchlings sex ratio. This suggests overestimation of hatchlings sex ratios and/or, less likely, differential mortality of females during the first months of life. Alternatively, the Madeira Island aggregation may be recruiting males from other geographical sources such as the Mediterranean and the Cape Verde.

The groundwater level in a fractured rock aquifer in Sweden was found to respond quickly to rainfall, although the bedrock was covered by 10-m-thick till soil. A considerable portion of the response was caused by surface loading, i.e., by the weight increase of the soil due to the addition of water from precipitation, whereas the rest reflected recharge. The hypothesis that the bedrock aquifer was recharged by vertical flow from groundwater in the overlying soil was tested with a simple recharge model, in which the bedrock-groundwater levels were simulated from the soil-groundwater and estimated surface-loading variation. The model had three parameters: the ratio between the equivalent vertical hydraulic conductivity governing the recharge and the storage coefficient of the bedrock reservoir, the recession coefficient for the bedrock-groundwater level, and the bedrock-groundwater level at which the outflow ceases. The model could be reasonably well calibrated and validated to head observations in one of two boreholes. The fit to the seasonal variation was similar when calibrating the model with or without surface loading, but surface loading had to be included to properly simulate individual recharge events. The relative temporal variation in the fluxes could be determined by the calibration. The variation in the recharge was from À10% to +25% in relation to the mean flux. The variation in the discharge was only ±1%. By applying a storage coefficient of the reservoir of 5 · 10 À4 , the simulated mean recharge was about 20 mm yr À1 . The results support the hypothesis that the bedrock-groundwater at the site is fed by local recharge from the overlying soil aquifer.

The Indo-Pacific seagrass Enhalus acoroides (L.f.) Royle can reproduce by vegetative growth as well as sexually, by the production of seeds. To assess the role of environmental conditions in the occurrence of sexual reproduction in this dioecious species, spatio-temporal variation in flowering was investigated in the reef flats off Cape Bolinao, north-western Philippines. Flowering occurred year-round, but the intensity varied temporally and correlated with mean water temperature. Spatially, differences in flowering intensity correlated with available light as affected by turbidity and water depth. Exposure duration of female flowers to air seems to be crucial for pollination and subsequent seed setting, resulting in higher numbers of fruits in shallower sites. Contrary to previous hypotheses, no effect of tidal levels on the release of male flowers was observed. It is suggested that production of gas bubbles in photosynthesis plays a key role. The great discrepancy between observed flowering and the presence of peduncle scars on the rhizomes at the deeper sites suggests that early abortion is common here. The use of these scars to quantify flowering will lead to an overestimation of reproductive effort in deep sites. The rare occurrence of flowering in deep sites supports the contention that light availability is a key factor in successful flowering in E. acoroides. Allocation of biomass and nutrients (N, P) over various plant components suggests that sexual reproduction involves high cost in E. acoroides.

This study evaluates five methods to estimate crop evapotranspiration in greenhouse conditions. It compares their performance in relation to the evapotranspiration directly determined from water balance measurements (ETlys) in an irrigated lettuce (Lactuca sativa L.) crop during 9 weeks. Daily values of the reference evapotranspiration (ETo) from Class A pan (CAP), Piche atmometers (ATM), Andersson evaporimeters (ANE), FAO-Radiation (FRE) and FAO-Penman-Monteith (PME) equations were compared. The methods showed similar temporal variations but at different ranges as follows: ANE < CAP < FRE < PME < ATM. Furthemore, ETo had a clear correlation with solar radiation. Crop coefficients (Kc = ETlys/ETo) varied somewhat amongst the methods, but trends were identified for two periods: in the first week, the overall mean Kc was 0.3 (± 0.1) and in weeks 2 to 9 on average 0.6 (± 0.3).

The combination of functional magnetic resonance imaging (FMRI) and electroencephalography (EEG) has received much recent attention, since it potentially offers a new tool for neuroscientists that makes simultaneous use of the strengths of the two modalities. However, EEG data collected in such experiments suffer from two kinds of artifact. First, gradient artifacts are caused by the switching of magnetic gradients during FMRI. Second, ballistocardiographic (BCG) artifacts related to cardiac activities further contaminate the EEG data. Here we present new methods to remove both kinds of artifact. The methods are based primarily on the idea that temporal variations in the artifacts can be captured by performing temporal principal component analysis (PCA), which leads to the identification of a set of basis functions which describe the temporal variations in the artifacts. These basis functions are then fitted to, and subtracted from, EEG data to produce artifactfree results. In addition, we also describe a robust algorithm for the accurate detection of heart beat peaks from poor quality electrocardiographic (ECG) data that are collected for the purpose of BCG artifact removal. The methods are tested and are shown to give superior results to existing methods. The methods also demonstrate the feasibility of simultaneous EEG/FMRI experiments using the relatively low EEG sampling frequency of 2048 Hz. D

Roost microclimate plays an important role in the survival, growth and reproduction in microbats. Entering torpor is one of the main energy saving mechanisms commonly used by microbats. The use of torpor is affected by roost microclimate and seasonally differs between the two sexes in relation to their reproductive condition. Consequently, thermal properties of male and female roosts should differ. To test this hypothesis, we compared temperature parameters of two anthropogenic day roosts of Daubenton’s bats with a different structure of the population inhabiting them. In accordance with our predictions, the roost occupied by a male-dominated colony was colder and more fluctuant than the maternity roost with a female-dominated population. However, using of the two roosts changed during the season in response to changing energetic demands of the two sexes. While males were almost absent in the warmer maternity roost during pregnancy and lactation, they appeared in this roost during the post-lactation when mating starts. In contrast, females did not use the colder (male) roost until the time of weaning of juveniles, i.e., the time when their thermoregulatory needs change and they may benefit from using colder roost. Our study provides the evidence that the same roost may be used by individuals of different sex and reproductive state in different periods of the year. Generalizations about roost selection without knowledge of temporal variation in roost use and microclimatic conditions should be taken with caution. Anthropogenic roosts may be advantageous to Daubenton’s bats as these can provide a variety of suitable microclimates and/or more space for roosting than tree cavities.

Zooplankton were collected from Lake Taal between January and December 2008 in order to test for differences in species composition and abundance between a lake basin with intensive fish cage (FC) aquaculture and an open water area without FCs. Most species showed similar patterns of occurrence in both basins while having differences in abundance. Several rotifer species were more abundant in FC sites most of the year, while for microcrustaceans higher abundances in FC sites only happened during the first 2 months. Their distribution is attributed to the presence of higher nutrient levels in FC sites as well as wind-induced basin-wide water movements during the different monsoon seasons which disperse plankton and nutrients from FC sites to other parts of the lake. Zooplanktonic indicators, such as the Brachionus–Trichocerca quotient (Q B/T) and the ratio of calanoids to cladocerans and cyclopoids, clearly demonstrate the eutrophic state of the lake. A comparison with previous studies suggests that the lake was already eutrophic prior to the introduction of aquaculture in the 1970s. The trophic conditions in Lake Taal may be attributed to the lakes’ tropical and volcanic nature, with productivity further enhanced by increased nutrient input from aquaculture.

Tigers (Panthera tigris) are endangered wild felids whose elusive nature and naturally low densities make them notoriously difficult to count. We present 7 years of camera trapping, tracking, and observational data on a local tiger population in Chitwan National Park, Nepal, to quantify changes in abundance of demographic groups and to identify underlying causes. Mean abundance in the 100-km 2 study area was 18 tigers, but there was high variance among years. Transients were generally recorded at low levels, but there were large oscillations in numbers of tiger offspring, driven by infanticide perpetrated by male tigers taking over territories. The number of breeding animals in the study area remained relatively stable, with about 6 breeding females and 1 or 2 breeding males. The high density of breeding adults in Chitwan National Park highlights the region as a potential stronghold for tigers. Concentrating on counting breeding animals increases the power of monitoring programs to detect change over time. An alternative approach is to carry out surveys on a scale large enough to encompass sufficient territories to compensate for the local impacts of periodic turnover of adult males on total abundance.

The interpretation of the spatial and temporal patterns of variation in organochlorine concentrations in marine mammal populations is complex because of the lack of wide-scale, long-term surveys. Therefore the results from several surveys must be combined and this causes undesired heterogeneity due to differences in the sampling and analytical techniques used and in the biological characteristics of the individuals sampled. Moreover, information is not homogeneously distributed in either space or in time.

In the Okavango Delta (about 28,000 km2) the number of identified species is 1,300 for plants, 71 for fish, 33 for amphibians, 64 for reptiles, 444 for birds, and 122 for mammals. The local occurrence of different species of these taxonomic groups in the Okavango Delta is mainly due to a hydrological gradient from permanent streams and swamps to seasonal floodplains, riparian woodlands, and dry woodlands. This level of species diversity is normal for the southern African region, and all analyzed aquatic groups are composed of ubiquitous species with an additional significant proportion of species originating from northern, more tropical systems. Cyclical variations in climate over thousands of years have created a huge wetland complex in the upper Zambezi and Okavango Rivers during wet phases. This wetland complex has fragmented into the Okavango Delta and other large wetlands in Zambia during dry phases. There are no endemic species in the Okavango Delta while the South-central African wetland complex is a centre of endemism. Species diversity of the Okavango Delta is a consequence of this unique environment, with dynamic shifts in flooding patterns that in turn force constant changes in patterns of plant succession and dependent animals. Temporal variations in flooding also cause accumulation and sudden mobilization of nutrients which are readily used by well adapted plant species. As a consequence, locally high biological productivity occurs, which in turn results in high numbers of grazing mammals.

We studied seasonal variation in population attributes of arbuscular mycorrhizal (AM) fungi over 2 years in four sites of temperate grasslands of the Argentinean Flooding Pampas. The sites represent a wide range of soil conditions, hydrologic gradients, and floristic composition. Lotus glaber, a perennial herbaceous legume naturalised in the Flooding Pampas, was dominant at the four plant community sites. Its roots were highly colonised by AM fungi. Temporal variations in spore density, spore type, AM root colonisation, floristic composition and soil chemical characteristics occurred in each site and were different among sites. The duration of flooding had no effect on spore density but depressed AM root colonisation. Eleven different types of spores were recognized and four were identified. Two species dominated at the four sites: Glomus fasciculatum and Glomus intraradices. Spore density was highest in summer (dry season) and lowest in winter (wet season) with intermediate values in autumn and spring. Colonisation of L. glaber roots was highest in summer or spring and lowest in winter or autumn. The relative density of G. fasciculatum and G. intraradices versus Glomus sp. and Acaulospora sp. had distinctive seasonal peaks. These seasonal peaks occurred at all four sites, suggesting differences among AM fungus species with respect to the seasonality of sporulation. Spore density and AM root colonisation when measured at any one time were poorly related to each other. However, spore density was significantly correlated with root colonisation 3 months before, suggesting that high colonisation in one season precedes high sporulation in the next season.

Features of the frontal bone that are conventionally used to distinguish among fossil hominin groups were quantitatively examined. Fifty-five fossil crania dating from the early to the late Pleistocene were analyzed. Using a modified pantograph, outlines of the frontal bone were collected along the midsagittal and two parasagittal planes. The profile from nasion to bregma, as well as two profiles above the medial and lateral sections of the orbit, respectively, extending from the orbital margin to the coronal suture were traced. The outlines were measured using Elliptical Fourier Function Analysis (EFFA), which enabled a quantification of aspects of the frontal bone that have historically been described primarily in nonmetric or linear terms. Four measurements were obtained: 1) overall morphology as expressed in the Fourier harmonic amplitudes; 2) maximum projection of the supraorbital torus at three points along the browridge (glabella and the medial and lateral aspects of the torus above the orbit); 3) maximum distance of the frontal squama from the frontal chord, capturing forehead curvature; and 4) nasion-bregma chord length. The results indicate that the midsagittal profile is significantly different among all Pleistocene groups in analyses that include both size and shape, as well as size-adjusted data. Homo erectus is significantly different from the late Pleistocene groups (Neandertals and early modern H. sapiens) in glabellar projection. Anatomically modern humans are significantly different from all other groups in both raw and size-standardized analyses of all three outlines that captured overall morphology, as well as forehead curvature and lateral supraorbital torus prominence, and middle Pleistocene Homo are significantly different in both medial and lateral overall parasagittal form. However, for the majority of analyses there were no significant differences among the Pleistocene archaic groups in supraorbital torus projection, frontal squama curvature, nasion-bregma chord length, or overall frontal bone morphology.

The eVect of land use on the biogeochemistry of small tropical rivers and their estuaries was studied using the Kallada River and Ashtamudi estuary located in the State of Kerala, India, as a model system. Water, suspended matter and sediments collected during the monsoon and intermonsoon periods in 2002 and 2003 were analyzed for dissolved nutrients (nitrate, nitrite, phosphate, silicate) and for phytoplankton abundance and composition, amino acid contents and stable carbon (C)) and nitrogen (N) isotope ratios. Seasonal and spatial variations of dissolved nutrients and suspended matter along the course of the river point to distinct diVerences in the C and N sources that are controlled by hydrology, geology and land use. Unusually low concentrations of dissolved silicate and suspended matter suggest low erosion rates of the Precambrian basement rocks and the Wrm lateritic soils in non-agricultural areas. Most dissolved nutrients and suspended particulate organic matter originated from fertilized agricultural soils. The biogeochemistry of sedimentary organic matter indicates that most of the Kallada River load is deposited in the upper Ashtamudi estuary, while the middle and lower parts have a stronger marine inXuence. The spatio-temporal variation of dissolved and particulate river Xuxes clearly indicates an eVect of land use and land cover on the biogeochemistry of the Kallada River. While the phosphate yield was high (6 £ 10 3 mol km ¡2 year ¡1 or 185 kg km ¡2 year ¡1 ), the N yield was relatively low (10 £ 10 3 mol km ¡2 year ¡1 or 141 kg km ¡2 year ¡1 ), which is unlike the situation in many other densely populated regions of tropical Asia.

Previous studies have provided prima facie evidence that runoff from the MI motorway, UK, affects both the quality of the receiving water and the biota living there, in sites short distances from point sources-i.e., possible worst-case situations. Because discharges contain a wide variety of contaminants, both the identification of toxicants and the establishment of causal relationships between observed changes in waterhediment quality and biology are often difficult. In this particular case, the problem was addressed by conducting a series of toxicity tests using the benthic amphipod Gummnruspulex. The abundance of this species was greatly reduced downstream of the point where motorway runoff entered the stream. Stream water contaminated with motorway runoff was not toxic to G. pulex. However, exposure to contaminated sediments resulted in a slight reduction in survival over 14 d, and sediment manipulation experiments identified hydrocarbons, copper, and zinc as potential toxicants. Spiking experiments confirmed the importance of hydrocarbons, and fractionation studies indicated that most of the observed toxicity was due to the fraction containing polycyclic aromatic hydrocarbons. Animals exposed to contaminated sediments and water spiked with sediment extract accumulated aromatic hydrocarbons in direct proportion to exposure concentrations.

Evaporation is an important component of the hydrological cycle and its change would be of great significance for water resources planning, irrigation control and agricultural production. The main purpose of this study was to investigate temporal variations in pan evaporation (Epan) and the associated changes in maximum (Tmax), mean (Tmean) and minimum (Tmin) air temperatures and precipitation (P) for 12 stations in Hamedan province in western Iran for the period 1982–2003. Significant trends were identified using the Mann–Kendall test, the Sen’s slope estimator and the linear regression. Analysis of the Epan data revealed a significant increasing trend in 67% of the stations at the 95% and 99% confidence levels. To put the changes in perspective, the trend in Epan averaged over all 12 stations was (+)160 mm per decade. Trend analysis of the meteorological variables for examination of causal mechanisms for Epan changes showed warming trends in Tmax, Tmean and Tmin series in almost all the stations, which were significant over half of the total stations. On the contrary, no significant changes in precipitation were found approximately at all of the stations. Furthermore, a moderate positive correlation was observed between Epan and Tmax, Tmean and Tmin, while a inverse correlation was found between Epan and P data. The results indicated that the study area has become warmer and drier over the last 22 years, hence the evaporative demands of the atmosphere and thereby crop water requirements have increased.

The oxygen isotope compositions of 28 mammoth tooth enamel samples from Estonia, Latvia, Lithuania, Poland and Denmark provide new quantitative records of the middle to late Weichselian climate in northern Europe. The new d 18 O data was combined with records of oxygen isotope values from earlier investigations on European mammoth tooth enamel and palaeogroundwaters to study the spatial patterns and temporal variations in the oxygen isotope composition of precipitation and the thermal climate over much of Europe. The reconstructed geographical distribution of d 18 O in precipitation during 52e24 ka reflects the progressive isotopic depletion of air masses moving northeast, consistent with a westerly source of moisture for the entire region, and a circulation pattern similar to that of the present-day. Regional long-term average d 18 O w values were 0.6e4.1& lower than at present, the largest changes recorded for the currently maritime influenced southern Sweden and the Baltic region. The application of regionally varied d/T-slopes, estimated from palaeogroundwater data and modern correlations, yield reasonable estimates of glacial surface temperatures in Europe and imply 2e9 C lower long-term mean annual surface temperatures during the glacial period.

The biomass variation and the reproduction of the natural Gracilaria gracilis bed in Bahía Bustamante (Patagonia, Argentina) were analyzed for 2 years, with the aim of determining the present situation of the population for an updated status overview; establishing the relevant features of the temporal variation in both biomass and reproductive states in relation to environmental factors, epiphytes and associated algae; and assessing carpospore availability for future spore-culture development. Field measurements and sampling were performed monthly between March 2006 and February 2008. In both years, G. gracilis biomass presented marked seasonal variations, with a minimum in winter and a maximum in late spring and in summer. During both years, coexistence of the three life-cycle phases was found, with dominance of tetrasporophytes. Two data sets from individuals originated from sexual reproduction (tetraspores and carpospores) and from asexual reproduction by thallus fragmentation were analyzed separately. In the fragmentation fraction, tetrasporophyte frequencies remained higher than those for gametophytes. However, in the spore-originated fraction, a generation ratio close to 0.5 was observed. Female gametophytes bearing cystocarps were always present, with a maximum in summer and autumn. Biological data were related to environmental factors by means of canonical correspondence analysis (CCA). The first year was characterized by higher biomass values of G. gracilis and Undaria pinnatifida, lower epiphytism, larger Gracilaria thalli and greater proportion of mature tetrasporophytes and gametophytes. The second year was characterized by a high proportion of Gracilaria vegetative thalli and high epiphyte density. The best time to obtain spores from cystocarpic thalli would be in summer and early autumn.

In pipes with very large diameters, slug bubbles cannot exist. For this reason, the characteristics of twophase flow in large pipes are much different than those in small pipes. Knowledge of these characteristics is essential for the prediction of the flow in new nuclear reactor designs which include a large chimney to promote natural circulation. Two of the key parameters in the prediction of the flow are the void fraction and flow regime. Void fraction measurements were made in a vertical tube with diameter of 0.15 m and length of 4.4 m. Superficial gas and liquid velocities ranged from 0.1 to 5.1 m/s and from 0.01 to 2.0 m/s, respectively. The measured void fractions ranged from 0.02 to 0.83. Electrical impedance void meters at four axial locations were used to measure the void fraction. This data was verified through comparison with previous data sets and models. The temporal variation in the void fraction signal was used to characterize the flow regime through use of the Cumulative Probability Density Function (CPDF). The CPDF of the signal was used with a Kohonen Self-Organized Map (SOM) to classify the flow regimes at each measurement port. The three flow regimes used were termed bubbly, cap-bubbly, and churn flow. The resulting flow regime maps matched well with the maps developed previously through other methods. Further, the flow regime maps matched well with the criteria which were proposed based on criteria.

CITATIONS 8 READS 76 5 authors, including: Some of the authors of this publication are also working on these related projects: Marine Biodiversity Southern Gulf of Mexico View project The role of temperature in the reproductive regulation of Octopus maya. View project Alberto J Sánchez Universidad Juárez Autónoma de Tabasco Artículo recibido: 14 de septiembre de 2006, aceptado: 12 de octubre de de 2007

As part of a joint Brazilian–French project, entitled ‘Hydrology and Geochemistry of the Amazon Basin’, we carried out a seven-year study (1994–2000) on the distribution, behaviour and flux of particulate and dissolved organic carbon in the Amazon River and its main tributaries (the Negro, Solimões, Branco, Madeira, Tapajós, Xingú and Trombetas rivers).The concentrations of particulate and dissolved organic carbon varied from one river to another and according to the season, but dissolved organic carbon (DOC) always accounted for about 70% of the total organic carbon (TOC). The mean concentration of dissolved organic carbon was 6·1 mg l−1 in the Madeira River, 5·83 mg l−1 in the Solimões River and 12·7 mg l−1 in the Negro River. The percentage in weight of the particulate organic carbon decreased as the concentration of suspended matter increased. The Solimões River contributed the most carbon to the Amazon River: about 500 kg C s−1 during the high water period and about 300 kg C s−1 during the low water period. However, the temporal variations in organic carbon in the Amazon River (i.e. downstream of Manaus) are basically controlled by inputs from the Negro River and its variations. The Negro River does not produce a simple dilution effect. During the high water period (between March and August) the TOC flux, calculated as the sum of the Solimões, Negro and Madeira tributaries, was about 5·7 × 1013 g C yr−1, whereas during the low water period (between September and February) the TOC flux was about 2·6 × 1013 g C yr−1.The mean annual flux of TOC at Óbidos (the final gauging station upstream of the estuary) was about 3·27 × 1013 g C yr−1 (i.e. 32·7 ± 3·3 Tg yr−1). Of this, the flux of DOC represents about 2·7 × 1013 g C yr−1 and the flux of particulate organic carbon (POC) represents about 0·5 × 1013 g C yr−1. The mean annual input of TOC by all tributaries (Negro, Solimões, Madeira, Trombetas, Tapajós and Xingú) was about 2·8 × 1013 g C yr−1. When we compared this input with the output recorded at Óbidos (3·27 × 1013 g C yr−1), we found that the amount of organic carbon increased (about 0·4 × 1013 g C yr−1). This shows that other important sources of organic carbon exist in the lower reaches of the Amazon River. These inputs can be attributed to the adjacent floodplain lake system, called ‘várzea’. Copyright © 2003 John Wiley & Sons, Ltd.

In the present study, a back propagation feedforward artificial neural network (ANN) model was developed for the computation of event-based temporal variation of sediment yield from the watersheds. The training of the network was performed by using the gradient descent algorithm with automated Bayesian regularization, and different ANN structures were tried with different input patterns. The model was developed from the storm event data (i.e. rainfall intensity, runoff and sediment flow) registered over the two small watersheds and the responses were computed in terms of runoff hydrographs and sedimentographs. Selection of input variables was made by using the autocorrelation and cross-correlation analysis of the data as well as by using the concept of travel time of the watershed. Finally, the best fit ANN model with suitable combination of input variables was selected using the statistical criteria such as root mean square error (RMSE), correlation coefficient (CC) and Nash efficiency (CE), and used for the computation of runoff hydrographs and sedimentographs. Further, the relative performance of the ANN model was also evaluated by comparing the results obtained from the linear transfer function model. The error criteria viz. Nash efficiency (CE), error in peak sediment flow rate (EPS), error in time to peak (ETP) and error in total sediment yield (ESY) for the storm events were estimated for the performance evaluation of the models. Based on these criteria, ANN based model results better agreement than the linear transfer function model for the computation of runoff hydrographs and sedimentographs for both the watersheds.

Crime is a grave problem that affects all countries in the world. The level of crime in a country has a big impact on its economic growth and quality of life of citizens. In this paper, we provide a survey of trends of
supervised and unsupervised machine learning methods used for crime pattern analysis. We use a spatiotemporal dataset of crimes in San Francisco, CA to demonstrate some of these strategies for crime
analysis. We use classification models, namely, Logistic Regression, Random Forest, Gradient Boosting and Naive Bayes to predict crime types such as Larceny, Theft, etc. and propose model optimization
strategies. Further, we use a graph based unsupervised machine learning technique called core periphery structures to analyze how crime behavior evolves over time. These methods can be generalized to use for
different counties and can be greatly helpful in planning police task forces for law enforcement and crime prevention.