Individual Springs Research Articles

The associations between daily spring pollen counts, over-the-counter allergy medication sales, and asthma syndrome emergency department visits in New York City, 2002-2012.

BackgroundMany types of tree pollen trigger seasonal allergic illness, but their population-level impacts on allergy and asthma morbidity are not well established, likely due to the paucity of long records of daily pollen data that allow analysis of multi-day effects. Our objective in this study was therefore to determine the impacts of individual spring tree pollen types on over-the-counter allergy medication sales and asthma emergency department (ED) visits.MethodsNine clinically-relevant spring tree pollen genera (elm, poplar, maple, birch, beech, ash, sycamore/London planetree, oak, and hickory) measured in Armonk, NY, were analyzed for their associations with over-the-counter allergy medication sales and daily asthma syndrome ED visits from patients’ chief complaints or diagnosis codes in New York City during March 1st through June 10th, 2002-2012. Multi-day impacts of pollen on the outcomes (0-3 days and 0-7 days for the medication sales and ED visits, respectively) were estimated using a distributed lag Poisson time-series model adjusting for temporal trends, day-of-week, weather, and air pollution. For asthma syndrome ED visits, age groups were also analyzed. Year-to-year variation in the average peak dates and the 10th-to-90th percentile duration between pollen and the outcomes were also examined with Spearman’s rank correlation.ResultsMid-spring pollen types (maple, birch, beech, ash, oak, and sycamore/London planetree) showed the strongest significant associations with both outcomes, with cumulative rate ratios up to 2.0 per 0-to-98th percentile pollen increase (e.g., 1.9 [95 % CI: 1.7, 2.1] and 1.7 [95 % CI: 1.5, 1.9] for the medication sales and ED visits, respectively, for ash). Lagged associations were longer for asthma syndrome ED visits than for the medication sales. Associations were strongest in children (ages 5-17; e.g., a cumulative rate ratio of 2.6 [95 % CI: 2.1, 3.1] per 0-to-98th percentile increase in ash). The average peak dates and durations of some of these mid-spring pollen types were also associated with those of the outcomes.ConclusionsTree pollen peaking in mid-spring exhibit substantive impacts on allergy, and asthma exacerbations, particularly in children. Given the narrow time window of these pollen peak occurrences, public health and clinical approaches to anticipate and reduce allergy/asthma exacerbation should be developed.Electronic supplementary materialThe online version of this article (doi:10.1186/s12940-015-0057-0) contains supplementary material, which is available to authorized users.

Preliminary results on the dynamics of particles and their size distribution at a karst spring during a snowmelt event

Summary Recharge events in karst catchments are often accompanied by rapid changes of electrical conductivity, temperature or turbidity in associated karst springs. Turbidity is usually used as a proxy for suspended matter. However, it is not capable to characterize suspended matter in detail as it lumps signals of particles of a wide range of sizes. Changes in particle size distribution (PSD) of suspended matter have rarely been measured although they may contain information on particles’ origin, transport, or mobilization. In few cases PSD could even be used to predict bacterial contamination of karst springs. This study is one among few, measuring concentrations of suspended particles in the size range of 0.5–150 μm on-site and in real-time. The study was performed during a single snow-melt event at one individual karst spring (Gallusquelle, Germany), the findings are therefore of preliminary character. Generally, the PSDs follow a power law (Pareto distribution). In some cases, however, a two parted Pareto distribution provides a better fit. The combination of chemograph analysis and turbidigraph separation demonstrates remobilized (autochthonous) and freshly infiltrated suspended (allochthonous) matter. Visually, there is no relation between PSD and the origin of the suspended matter. This may be caused by the superposition of signals from both origins. Therefore, utilizing the PSD as an indicator for the origin of suspended matter may be restricted to local applications. Furthermore, PSD does not seem to be a clear indicator for a bacterial contamination at the investigated spring, at least for this particular event. The study indicates, that the karst system itself and the type of discharge event may play a crucial role in the successful application of PSD as an adequate source indicator for suspended matter.

Recharge mixing in a complex distributary spring system in the Missouri Ozarks, USA

Toronto Springs is a complex distributary karst spring system with 11 perennial springs in the Missouri Ozarks, USA. Carroll Cave (CC) and Wet Glaize Creek (WG) were previously identified as principal recharge sources. This study (1) characterized physical and chemical properties of springs and recharge sources; (2) developed end-member mixing models to estimate contributing proportions of CC and WG; and (3) created a conceptual model for the system. Samples analyzed for major ions and specific conductivity, in conjunction with a rotating continuous monitoring program to identify statistically comparable baseflow conditions, were used to assess differences among the sites. Monitoring data showed that the springs differed depending upon recharge proportions. Cluster analysis of average ion concentrations supported the choice of CC and WG as mixing model end members. Results showed a range in the proportions of the recharge sources, from surface-water to groundwater dominated. A conceptual model suggests that a system of distinct conduits beneath the WG flood plain transmits water to the individual springs. These conduits controlled the end-member recharge contributions and water chemistry of the springs. Interpretation of relative proportions of recharge contributions extends existing knowledge of karst hydrologic geometry beyond that of point-to-point connections to revealing complex surface-water/groundwater mixing in heterogeneous distributary spring systems.

Analysis of Energy Efficiency of a Test Rig for Air Springs

During dynamic testing of vehicle air springs, work is required for loading the springs. This work is partially returned by the spring to the driving system during the release phase. Testing is energy-efficient when at least a portion of the returned work can be utilised. This was taken into account in the design of the new inovative test rig for the simultaneous testing of four air springs. There is a phase shift between the phases of loading individual air springs; thus, the work returned to the drive system by a spring during its release is also used for loading another spring. The test rig was constructed and operates in the laboratory of an air spring manufacturer. We developed a computer program to analyse the energy situation in the test rig. The program calculates the work required for loading the springs, power and friction for different sizes of springs and test conditions. In this paper, computational algorithms are deduced and the results of the calculation for the treated spring are presented. The energy situation in the test rig during start-up and operation is discussed, taking into account the energy loss due to the hysteresis of springs and friction losses. The friction losses are evaluated for different implementations of critical elements. The influence of a flywheel on conditions during the start-up and operation of the test rig is analysed.

A finite grid solution for circular plates on elastic foundations

The transmission of vertical or horizontal structural forces to the supporting soil is a challenge to analyze for structures on elastic foundation which represent a complex medium. The two-parameter elastic foundation model that provides a mechanical interaction between the individual spring elements shows a more realistic behavior of the soil reaction than does the single parameter Winkler model. Since the structural behavior of a beam resembles that of a strip in a plate, in this study, the exact stiffness and mass matrices of the beam element on two-parameter elastic foundation is extended to plates. The framework method that replaces a continuous surface by an idealized discrete system can represent a two-dimensional plate. In the light of this situation, circular plates are modeled as an assemblage of individual beam elements interconnected at their neighboring joints in radial and tangential direction. So, a useful tool called finite grid solution as a numerical method developed in this study lead to solve circular plates resting on two parameter elastic foundation problems. Examples for bending of ring, circular and annual plates on elastic foundation are solved to compare with known analytical solutions and other numerical solutions. The comparisons show that the literature and the computed results are compatible.

Effect of Balneotherapy in chronic low back pain treatment

The balneotherapy is a therapy that uses the mineral springs for the treatment of numerous diseases, and the physical properties of these waters may have a role in the mechanism of action of mineral water. Over the past decades, a re-assessment of the use of mineral water for the treatment of several diseases has taken place around the world. Chronic low back pain is a major public health problem in industrialized countries, it affects 80% of people and, in 85% of cases, the inaugural episode is followed by recorrencies. Its incidence and prevalence increases with age and is considered chronic when it persists for more than 7-12 weeks.The impoverished existing evidence contrasts with the popularity of these treatments and with the expenses incurred by insurers and health systems of some European countries (eg. Germany).The authors proposed reviewing the literature to clarify the present evidence regarding the effect of this therapeutic modality in the treatment of chronic low back pain. The meta-analysis of 2 randomized clinical trials concluded there was a significant reduction in pain intensity, measured on a 100mm visual analogue scale (VAS), in treated patients relative to controls. Individually, one of these studies also showed a decrease in analgesic consumption (p <0.01) and the other one showed an increase in functionality measured by the modified Schober test (p <0.001). One randomized study evaluated the VAS, lumbar mobility, and the Oswestry, EuroQoL-5D and Short Form-36 indices, with a significant improvement in all tests in the treatment group relative to the controls. The improvement observed in the first three lasted 10 weeks. It was also observed a significant decrease in the consumption of NSAIDs and analgesics in the treatment group, but the difference between groups was not statistically significant. Another randomized study showed an improvement in VAS (p <0,01), decrease in the paravertebral muscle spasms and sensitivity (p <0.01), as well as increased mobility (p <0.01) in patients treated for a period 3 months. In contrast, the improvement observed in the control group was only temporary and only in the VAS (p <0.01). In a nonrandomized study were evaluated pain intensity, Oswestry index, quality of life, use of NSAIDs/analgesics, and the subjective perception of disease for patients and observers. All parameters were significantly improved, and the effects lasted at least months. The mean age of the patients ranged from 39-44 to 64 years. The data collected showed significant improvements in pain, functionality, quality of life and consumption of NSAID/analgesic drugs in patients with chronic low back pain undergoing thermal therapy. As a major limitation, there were no double-blinded studies, since the physical and chemical properties of the mineral springs differ significantly from those found in tap water. We conclude that balneotherapy is an effective modality in the treatment of chronic low back pain in patients of middle age, being necessary more studies to validate thermal waters for individual springs, and pharmacoeconomic studies that evaluate the balneotherapy as a complementary modality in the management of low back pain is chronic.

Chemical and U–Sr isotopic variations in stream and source waters of the Strengbach watershed (Vosges mountains, France)

Abstract. This is the first comprehensive study dealing with major and trace element data as well as 87Sr/86Sr isotope and (234U/238U) activity ratios (AR) determined on the totality of springs and brooks of the Strengbach catchment. It shows that the small and more or less monolithic catchment drains different sources and streamlets with very different isotopic and geochemical signatures. Different parameters control the diversity of the source characteristics. Of importance is especially the hydrothermal overprint of the granitic bedrock, which was stronger for the granite from the northern slope; also significant are the different meteoric alteration processes of the bedrock causing the formation of 0.5 to 9 m thick saprolite and above the formation of an up to 1m thick soil system. These processes mainly account for springs and brooks from the northern slope having higher Ca / Na, Mg / Na, and Sr / Na ratios, but lower 87Sr/86Sr isotopic ratios than those from the southern slope. The chemical compositions of the source waters in the Strengbach catchment are only to a small extent the result of alteration of primary bedrock minerals, and rather reflect dissolution/precipitation processes of secondary mineral phases like clay minerals. The (234U/238U) AR, however, are decoupled from the 87Sr/86Sr isotope system, and reflect to some extent the level of altitude of the source and, thus, the degree of alteration of the bedrock. The sources emerging at high altitudes have circulated through already weathered materials (saprolite and fractured bedrock depleted in 234U), implying (234U/238U) AR below 1, which is uncommon for surface waters. Preferential flow paths along constant fractures in the bedrocks might explain the – over time – homogeneous U AR of the different spring waters. However, the geochemical and isotopic variations of stream waters at the outlet of the catchment are controlled by variable contributions of different springs, depending on the hydrological conditions. It appears that the (234U/238U) AR are a very appropriate, important tracer for studying and deciphering the contribution of the different source fluxes at the catchment scale, because this unique geochemical parameter is different for each individual spring and at the same time remains unchanged for each of the springs with changing discharge and fluctuating hydrological conditions. This study further highlights the important impact of different and independent water pathways on fractured granite controlling the different geochemical and isotopic signatures of the waters. Despite the fact that soils and vegetation cover have a great influence on the water cycle balance (evapotranspiration, drainage, runoff), the chemical compositions of waters are strongly modified by processes occurring in deep saprolite and bedrock rather than in soils along the specific water pathways.

Study of Thermal Water Resources in Sri Lanka Using Time Domain Electromagnetics (TDEM)

Thermal springs can be utilized as an environmental friendly source of renewable energy, as well as for other purposes. Time domain electromagnetic (TDEM) method is used as an accessory tool in geothermal exploration to investigate the local heterogeneities in geology. The study consists of two of the thermal springs in Sri Lanka, Wahawa and Mahaoya, both in the same crustal unit. Major structural discontinuities of the area vary between two peculiar fracture sets striking ENE and NW. Close relationships between these individual springs have been witnessed by their approximate major cation chemistries, which provoke the idea of geochemical provinces. Survey reveals the pathways of the heated water to the surface, at Wahawa, although the path is not clear at Mahaoya. Near surface resistivity diagrams can be used only to interpret the immediate depths of the springs. The expected structural relationships may be identified with a grid of TDEM soundings encompassing both the spring systems.

Stable isotope analysis of the karst hydrological systems in the Bay of Kvarner (Croatia)

Here we present the results of the first systematic analysis of the stable isotope composition of the karst hydrological systems in the Bay of Kvarner. Gaussian mixture modelling, time series analysis and autoregressive integrated moving average (ARIMA) modelling were applied using the stable isotope compositions of the karst groundwater. This study revealed that the recharge is dominated by winter precipitation, the dual-porosity system is dominated by baseflow, the hinterlands of the individual springs have different degrees of karstification and the springs within the Rječina River catchment have higher recharge elevations than the springs in the Bakar Bay catchment.

Regional outbreak dynamics of Dothistroma needle blight linked to weather patterns in British Columbia, Canada

Dothistroma needle blight (DNB) has caused extensive mortality in plantations of lodgepole pine in northwestern British Columbia, Canada, and even mature pine trees in natural forests are succumbing. We examined a number of explanatory models to determine which temperature or precipitation variable is most important in explaining DNB outbreak occurrence. We compared a multicentury tree-ring outbreak reconstruction with mean monthly temperature and total monthly precipitation during the individual and seasonal spring (April, May, June) and summer (July, August, September) months. A trend towards increased August minimum temperatures appears to be an important climate factor contributing to the spread of the disease. Graphical comparisons of total April precipitation reveal that periods of above-average precipitation coincided with periods of outbreak increase. Decreases in August minimum temperature also correspond to decreases in outbreak severity. Even more pronounced was a spike in spring precipitation and its association with the current epidemic. The correspondence of past outbreaks with periods of wet and warm conditions suggests that regional climate trends drive DNB behavior. The extent and severity of the current disease epidemic raises the possibility that the key factors that drive outbreaks have become more frequent, enabling the emergence of DNB as a serious disease.

Persistence in the desert: ephemeral waterways and small‐scale gene flow in the desert spring amphipod, Wangiannachiltonia guzikae

Summary The springs of the Great Artesian Basin (GAB) in central Australia support a unique, but threatened ecosystem adapted to permanent fresh water in a desert landscape. Taxa within these springs are short‐range endemics, with very limited distributions, making them highly susceptible to extinction. Knowledge of fine‐scale dispersal mechanisms will help to develop conservation management plans that maintain gene flow and, by extension, the genetic diversity of these populations. This study focused on determining dispersal capabilities of the endemic GAB spring amphipod, Wangiannachiltonia guzikae, in an area &lt;4 km2. Using 11 microsatellite loci, 288 individuals were genotyped from 14 springs. Despite the very small area, low levels of gene flow and significant population differences were found among individual spring populations. Microgeographical genetic structure is clearly evident, and fine‐scale dispersal is significantly correlated with temporary waterways between springs. This pattern of genetic divergence supports the stream hierarchy model of population structure and suggests that connectivity between springs is critical for gene flow, although the precise mechanism of dispersal is still open for interpretation.

Individual migration timing of common nightingales is tuned with vegetation and prey phenology at breeding sites

BackgroundThe timing of migration substantially influences individual fitness. To match peak requirements with peak resource availability, we hypothesized that individual migrants schedule spring migration in close relation to seasonal changes in environmental conditions along the route and particularly, at the breeding destination.To test this hypothesis, we investigated the timing of spring migration in male common nightingales Luscinia megarhynchos, a small Palearctic-African long-distance migrant, by linking spring migration timing to the phenology of local environmental conditions at non-breeding migratory stopover and breeding sites. In particular, we related individual migration decisions (i.e. departure and arrival) of nine males to site-specific vegetation phenology (based on remotely sensed vegetation index) and a proxy of food availability (based on insects’ thermal requirements).ResultsWe found weak relation of departures from non-breeding and no relation of stopover timing with local phenology. However, our results showed that individuals, which departed early from their non-breeding sites and arrived early at the breeding site closely matched spring green-up there. Early arrival at the breeding site meant also a close match with peak food availability for adults and in a time-lagged manner, for offspring.ConclusionOur findings suggest that male nightingale used cues other than local phenology for their departure decisions from non-breeding grounds and that there is some evidence for equalizing late departures during the course of migration.

Stiffness of the Roller Screw Mechanism by the Direct Method

In this paper, the direct stiffness method is used to construct a stiffness model of the roller screw mechanism. This method models the entire roller screw mechanism as a large spring system composed of individual springs representing the various compliances. In addition to predicting the overall stiffness of the mechanism, the direct stiffness method can calculate the distribution of load across the threads of the individual bodies. With the load on the individual threads known, the contact stresses can be calculated. This allows for a better understanding of the sensitivities of stiffness and contact stresses in the mechanism with various design parameters and can ultimately be used to design roller screws that are stiffer and with lower contact stresses.

Flow dynamics and age of groundwater within a humid equatorial active volcano (Mount Cameroon) deduced by δD, δ18O, 3H and chlorofluorocarbons (CFCs)

Summary We used environmental tracers (δD, δ 18 O, 3 H and chlorofluorocarbons (CFCs)) to establish the groundwater flow system within the Mount Cameroon area: a 4090 m high active entirely alkaline volcano located within a humid equatorial region. Seventy-five ground and surface water samples (68 spring samples, 6 borehole samples and 1 stream sample) were collected around the volcano during the wet (October–November 2010) and dry seasons (January–February 2010) as well as 10 rain samples in June–September 2010 in order to establish recharge elevations, apparent ages (residence times) and groundwater flow system in the fractured volcanic (basaltic) aquifers. The δ 18 O and δD composition of rainwater and groundwater in the Mount Cameroon area fit the Douala Local Meteoric Water Line (DLMWL). The recharge elevations of the individual springs were calculated from their δ 18 O-values and the equation of the altitude gradient (−0.16‰ δ 18 O/100 m) of precipitation on the mountain. For springs sampled during the two seasons, dry season samples have higher recharge elevations than rainy season samples. Seasonal variation exists in the tritium values as rainy season samples systemically are higher than those of the dry season samples . This implies the input of new water from the rain causing the groundwater system to rejuvenate. Apparent ages for the Mount Cameroon springs calculated from CFCs based on the Piston Flow model range from 10 to approximately 57 years. CFC apparent ages for rainy season samples are systemically younger than those of dry season samples. There is seasonal variation in groundwater flow system in the Mount Cameroon area and also along the different flanks of the volcano. The groundwater flow system is conceptualized by 2 models; a Bypass/piston flow model for the flow system during the rainy season and a binary mixing/piston flow model characterizes the flow system during the dry season.

Monitoring temporal dynamics of Great Artesian Basin wetland vegetation, Australia, using MODIS NDVI

The Great Artesian Basin springs (Australia) are unique groundwater dependent wetland ecosystems of great significance, but are endangered by anthropogenic water extraction from the underlying aquifers. Relationships have been established between the wetland area associated with individual springs and their discharge, providing a potential means of monitoring groundwater flow using measurements of vegetated wetland area. Previous attempts to use this relationship to monitor GAB springs have used aerial photography or high resolution satellite images and gave sporadic temporal information. These “snapshot” studies need to be placed within a longer and more regular context to better assess changes in response to aquifer draw-downs. In this study we test the potential of 8 years of Moderate Resolution Imaging Spectroradiometer Normalised Difference Vegetation Index data as a long-term tracer of the temporal dynamics of wetland vegetation at the Dalhousie Springs Complex of the Great Artesian Basin. NDVI time series were extracted from MODIS images and phenologies of the main wetland vegetation species defined. Photosynthetic activity within wetlands could be discriminated from surrounding land responses in this medium resolution imagery. The study showed good correlation between wetland vegetated area and groundwater flow over the 2002–2010 period, but also the important influence of natural species phenologies, rainfall, and anthropogenic activity on the observed seasonal and inter-annual vegetation dynamics. Declining trends in the extent (km2) of vegetated wetland areas were observed between 2002 and 2009 followed by a return of wetland vegetation since 2010. This study underlines the need to continue long-term medium resolution satellite studies of the GAB to fully understand variability and trends in the spring-fed wetlands. The MODIS record allows a good understanding of variability within the wetlands, and gives a high temporal-frequency context for less frequent higher spatial resolution studies, therefore providing a strong baseline for assessment of future changes.

Mechanical Model for Non Ductile Reinforced Concrete Columns

Column failure is the primary cause of collapse during earthquakes for many existing reinforced concrete buildings. The main objective of this article is to develop a macro model to reproduce the lateral load–deformation response of reinforced concrete columns with limited ductility due to degradation of shear resistance. This model will eventually be used to perform probabilistic assessments of collapse risk for existing reinforced concrete frame structures, and hence must be computationally efficient. Current modeling approaches for reinforced concrete components provide a reasonably accurate prediction of flexural and longitudinal bar slip response, while shear deformations and, in particular, post-peak shear behavior needs further development. The shear response introduced in this article is based on a mechanical approach for pre-peak, point of shear failure, and post-peak behavior of reinforced concrete columns. Flexural, shear, and longitudinal bar slip responses are simulated by individual springs in series. These springs are combined to obtain the total lateral response of the column. The column model has been implemented in OpenSees and validated using data from column tests representing a broad range of design parameters typical of older reinforced concrete frames.

Phylogenetic and phylogeographic analysis of the genus Orestias (Teleostei: Cyprinodontidae) in the southern Chilean Altiplano: the relevance of ancient and recent divergence processes in speciation

This study presents phylogenetic molecular data of the Chilean species of Orestias to propose an allopatric divergence hypothesis and phylogeographic evidence that suggests the relevance of abiotic factors in promoting population divergence in this complex. The results reveal that diversification is still ongoing, e.g. in the Ascotán salt pan, where populations of Orestias ascotanensis restricted to individual freshwater springs exhibit strong genetic differentiation, reflecting putative independent evolutionary units. Diversification of Orestias in the southern Altiplano may be linked to historical vicariant events and contemporary variation in water level; these processes may have affected the populations from the Plio-Pleistocene until the present.

Microspring Characterization and Flip-Chip Assembly Reliability

Electronics packaging based on stress-engineered spring interconnects has the potential to enable integrated IC testing, fine pitch, and compliance not readily available with other technologies. We describe new spring contacts which simultaneously achieve low resistance <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex Notation="TeX">$({&lt;}{\rm 100}~{\rm m}\Omega)$</tex> </formula> and high compliance <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex Notation="TeX">$({&gt;}{\rm 30}~\mu{\rm m})$</tex></formula> in dense 2-D arrays (180–180- <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex Notation="TeX">$\mu{\rm m}$</tex></formula> pitch). Mechanical characterization shows that individual springs operate at approximately 150- <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex Notation="TeX">$\mu{\rm N}$</tex></formula> force. Electrical measurements and simulations imply that the interface contact resistance contribution to a single contact resistance is <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex Notation="TeX">${&lt;}{\rm 40}~{\rm m}\Omega$</tex> </formula> . A daisy-chain test die consisting of 2844 contacts is assembled into flip-chip packages with 100% yield. Thermocycle and humidity testing suggest that packages with or without underfill can have stable resistance values and no glitches through over 1000 thermocycles or 6000 h of humidity. This paper suggests that integrated testing and packaging can be performed with the springs, enabling new capabilities for markets such as multichip modules.

Climatology of surface chlorophyll a, autumn‐winter and spring blooms in the southwest Pacific Ocean

Ocean color data from the 13 year Sea‐viewing Wide Field‐of‐view Sensor mission are used to examine the distribution of surface chlorophyll a in the southwest Pacific Ocean. The mean surface chlorophyll field is similar to that found by previous workers, with elevated levels in the Subtropical Front and around the subantarctic islands that have an associated shelf. The annual cycle in surface chlorophyll shows a ubiquitous summer bloom in subantarctic water, with autumn, winter, and spring blooms variously in subtropical water and across the Subtropical Front. The autumn blooms progress equatorward with time at the same rate as wind stress. This supports the idea that the autumn bloom develops in response to increased wind stress, with a likely mechanism for the bloom being mixing to the surface of the deep chlorophyll maximum, and/or increased production due to entrainment of nutrients. The spring bloom progresses poleward with time. It starts after the mixed layer reaches its deepest, and its timing appears to be linked to the reduction in wind stress in spring. Under the assumption that all tracers are well mixed to the seasonal thermocline in autumn and winter, we conclude that vertically integrated chlorophyll increases at all latitudes in subtropical water during autumn and winter. Unfortunately, carbon‐to‐chlorophyll ratios are not known well enough to determine whether the same is true for vertically integrated carbon biomass. Individual spring blooms show significant spatial structure and are different from year to year. This leads to low spatial coherence for the temporal variability in surface chlorophyll.

Conservation of the endangered red-finned blue-eye, Scaturiginichthys vermeilipinnis, and control of alien eastern gambusia, Gambusia holbrooki, in a spring wetland complex

The red-finned blue-eye is the only pseudomugilid fish known from inland Australia and it is found only within an isolated cluster of Great Artesian Basin springs on Edgbaston Reserve in central-western Queensland. Surveys conducted in early 2009 revealed that red-finned blue-eye was present in four individual springs and that invasion of the spring complex by alien eastern gambusia was the most likely factor contributing to local extirpations. A three-year project commenced in the same year, with the twin aims of investigating methods for removing gambusia from springs and relocating small populations of red-finned blue-eye to fish-free springs. Gambusia removal with rotenone has been successful in a trial spring at Edgbaston and aquatic invertebrates have not been adversely affected. From a total of seven relocation events conducted in the same period, red-finned blue-eye populations have persisted in three. The results indicate that gambusia removal and red-finned blue-eye relocation are both suitable methods for red-finned blue-eye conservation, and as the fish is both endangered and declining, these methods and other strategies such as captive breeding should be implemented to prevent species extinction.