Does temporal and spatial segregation explain the complex population structure of humpback whales on the coast of West Africa?

Humpback whales (Megaptera novaeangliae) in the Southeastern Atlantic Ocean (International Whaling Commission ‘Breeding Stock B’—BSB) are distributed from the Gulf of Guinea to Western South Africa. Genetic data suggest that this stock may be sub-structured, but it remains unknown if this is due to reproductive segregation. This paper evaluates the spatial and temporal population structure of BSB humpback whales using a combination of maternally and bi-parentally inherited markers. The genetic differentiation that we identify in this study could be due to a combination of (1) spatial and/or temporal segregation on breeding grounds in the greater Gulf of Guinea, (2) the possibility of maternally inherited site fidelity to specific feeding grounds and (3) the use of two generalized but exclusive migratory routes (coastal and offshore) between feeding and breeding areas. Further, photo-identification and genetic sampling efforts in other areas of the Sub-Saharan Western Africa winter range and targeted deployment of satellite tags would help to clarify some of the apparent complexity in the population structure of animals biopsied in this region.     

Accessibility and trust: the two dimensions of consumers’ perception on sustainable purchase intention

The aim of this article is to shed new light on which dimensions compose sustainable purchase intention (SPI) with the purpose of understanding what moves consumers to a potentially more sustainable behaviour. Even though several studies have researched which factors influence consumer’s intention to buy in a more sustainable way, no comparable research in consumer behaviour was found studying these dimensions in a triple bottom line perspective (profit, people, and planet) that could also provide future corporate and academic applications. Therefore, this article proposes a new construct – Consumers’ Perception on SPI, defined using the C-OAR-SE procedure and measured using exploratory and confirmatory factor analysis using two different samples. In-depth interviews and online survey to actual consumers of sustainable products were undertaken in partnership with a sustainable project using its database, guaranteeing that real consumers’ perceptions were gathered for this study. The construct is proposed with two dimensions (measured by nine items): Accessibility (including facets such as product lower pricing, availability in stores, and being sold within a convenient proximity to home) and Trust (including consumers needs such as: to get to know and trust products through understanding the labels; to have had good experiences in the past or simply to have new trial opportunities). Theoretical and practical implications of the findings are also discussed.     

Effects of two forest types on the dynamics of four base cations along with rainfall partitioning in middle subtropical forests北大核心CSCD

盐基离子随穿透雨和树干茎流的迁移成为森林元素输入的重要组成部分.在迁移过程中,冠层淋溶、树干冲刷等改变了盐基离子含量,而不同林型的林冠特征、树皮性质等存在差异,因此盐基离子含量在不同林型中可能存在差异对米槠次生林和杉木人工林穿透雨、树干茎流进行为期4年的监测,对比研究4种盐基离子(K+、Ca2+、Na+、Mg2+)浓度和输入量的动态特征.结果显示:(1)米槠次生林树干茎流Ca2+、Mg2+浓度显著低于杉木人工林而K+浓度显著高于杉木人工林;穿透雨除Na+浓度外均为米槠次生林显著高于杉木人工林.穿透雨和树干茎流Na+浓度林型差异不显著.(2)两种林型盐基离子季节动态变化基本一致,在雨季旱季各有一个峰值,雨季浓度普遍低于旱季.米槠次生林盐基离子浓度稳定性普遍高于杉木人工林.(3)分析盐基离子浓度与降雨强度的关系发现:Ca2+、K+、Mg2+浓度随雨量级的增加而降低,Na+浓度随雨量级的增加而增加.(4)观测期间米槠次生林穿透雨累计输入Ca2+、K+、Mg2+和Na+总量分别为47.97、35.17、7.15和12.94 kg/hm2,树干茎流累计输入Ca2+、K+、Mg2+和Na+总量分别为11.38、6.21、1.54和3.00 kg/hm2;杉木人工林穿透雨累计输入Ca2+、K+、Mg2+和Na+总量分别为47.24、26.63、6.43和11.55 kg/hm2,树干茎流累计输入Ca2+、K+、Mg2+和Na+总量分别为4.11、1.20、0.50和0.83 kg/hm2.米槠次生林的林内雨盐基离子输入量大于杉木人工林.总体而言,米槠次生林比杉木人工林有更高的养分输入,能更好地维持生态系统养分的供应;上述结果有助于进一步认识森林物质随水文过程的流动,可为人工林经营管理提供一定科学基础数据.(图6表1参36)     

Effect of blue tit song syntax on great tit territorial responsiveness – an experimental test of the character shift hypothesis

A previous study of geographic variation in blue tit (Parus caeruleus) song structure showed that changes in blue tit song syntax (i.e. presence/absence of a trill) are correlated with the breeding density of a close competitor, the great tit (P. major), and are not correlated with other environmental factors such as vegetation structure or blue tit breeding density. We tested the hypothesis that blue tit trilled song represents a character shift that evolved because it reduced territorial interactions with more dominant great tits. We conducted five sets of playback trials in three study populations (mainland southern France, Corsica and Denmark) presenting male great tits with blue tit trilled and untrilled songs and great tit songs. We found that great tits respond equally strongly to both blue tit untrilled songs and to great tit songs, but show a significantly weaker response to blue tit trilled songs. These findings are the first experimental evidence that interspecific competition may play an important role in macrogeographic variation of bird song. Received: 10 October 1999 / Received in revised form: 2 April 2000 / Accepted: 15 April 2000     

Effect of iron addition on the performance of anoxic-oxic membrane process and biological phosphorus removal北大核心CSCD

In order to solve the problem of poor treatment of phosphorus in membrane bioreactor (MBR) with long sludge retention time (SRT), a ferric salt was added to enhance phosphorus removal; FeCl36H2O (Fe/P = 2.0) was added to the reactor. The removal efficiency of nitrogen, organic matters, and phosphorus in the MBR was investigated systematically. Moreover, this study focused on the membrane performance, the change of active sludge flora, and the effect of adding a ferric salt on membrane fouling before and after the addition. It was seen that adding the ferric salt could not affect the removal of COD and NH4 +-N and the removal rate of COD and NH4 +-N reached over 90%. However, the average removal rate of phosphorus was 52%, while the removal rate increased by nearly 40% after adding the ferric salt. The effects of adding ferric salts on the dominant bacteria and biological phosphorus removal of activated sludge were further studied. The results showed that the addition of ferric salt (Fe/P = 2.0) decreased the diversity of active sludge flora and relative abundance of some phosphorusaccumulating organisms and had a negative effect on biological phosphorus removal. The analysis of transmembrane pressure difference (TMP) recording revealed that the concentration of iron salts did not exacerbate membrane fouling. The results showed that the concentration of iron salts entering the membrane bioreactor would reduce the relative abundance and phosphorus removal efficiency of the activated sludge in the system to a certain extent, but it had no obvious effect on membrane fouling. It allowed the effluent to attain acceptable standards, especially with respect to phosphorus removal efficiency. © 2018 Science Press. All rights reserved.     

Effects of planting density on the microclimate of rice population with different panicle-types and its yield components北大核心CSCD

Split-plot field experiments, with variety as the main plot, were designed to analyze the microclimate and character of R498 (curved panicle) and R499 (erect panicle) varieties of rice during the full heading day and on the 20th day after full heading. The planting densities assigned to the subplots were 0.23 m (line spacing) × 0.12 m (hole spacing), 0.27 m × 0.14 m, 0.33 m × 0.17 m, 0.38 m × 0.20 m, and 0.40 m × 0.21 m. The results showed that for all the planting densities, the maximum temperature of R499 increased by 1.52 ℃ on an average during the full heading stage, but decreased by 0.66 ℃ on the 20th day after full heading, in comparison to those of R498. The mean daily light intensities of R498 and R499 in sparse planting (0.38 m × 0.20 m, 0.40 m × 0.21 m) were higher than those of other planting density treatments during the full heading stage, being 43.56% and 16.22% higher, respectively, than that of the lowest daily light intensity. The daily light intensity of R498 was hindered by close planting (0.23 m × 0.12 m, 0.27 m × 0.14 m) while that of R499 was inhibited by sparse planting on the 20th day after the full heading stage. The rates of decrease of vertical light intensity of R498 and R499 in sparse planting were the highest among all the planting density treatments, their rates of decrease being 97.96% and 92.56%, respectively, during the full heading stage, and 94.81% and 91.10%, respectively, on the 20th day after the full heading stage. When the planting density was decreased, the variability of plant height, tiller number, and panicle curvature were greater for R499 than those of R498. The rates of incidence of sheath blight for R498 and R499 in the planting specification of 0.38 m × 0.20 m were 66.67% and 68.89%, respectively, which was the most serious among all the planting density treatments. On increasing the effective spike number and panicle weight, both R498 and R499 produced the highest yields with the planting specification of 0.27 m × 0.14 m, among all the planting density treatments. Even when the density was excessively reduced, the value of yield components did not increase any further. Thus, it is better to plant rice with curved panicles (R498) in a reasonable planting density (neither too close nor too sparse), and to plant rice with erect panicles in a reasonably close planting density. © 2018 Science Press. All rights reserved.     

Effect of temperature on growth and maturation pattern of <Emphasis Type="Italic">Caprella mutica</Emphasis> (Crustacea,Amphipoda): does the temperature–size rule function in caprellids?

Many ectothermal marine animals mature at larger sizes in lower temperature environments and at smaller sizes in higher temperature environments. This phenomenon is called the temperature–size rule. To examine whether this rule controls the appearance of large adults in a winter population of caprellids, individuals of Caprella mutica were reared at different temperatures. Caprellids at 5°C died at instar III before they reached maturity. In contrast, the animals reared at 10, 15 and 20°C lived to higher instars and reached maturity within their lifetime. Somatic growth pattern did not change between 10 and 20°C. Maturation instar of males was not affected by temperature. This indicates that the appearance of large adults in winter is not a result of a change in somatic growth pattern with temperature change. However, female maturation size becomes larger due to a delay in maturation at lower temperature. This, in turn, indicates that the temperature–size rule plays a role in the mechanism controlling the appearance of large female adults in winter populations.     

An approach for particle sinking velocity measurements in the 3–400?μm size range and considerations on the effect of temperature on sinking rates

The flux of organic particles below the mixed layer is one major pathway of carbon from the surface into the deep ocean. The magnitude of this export flux depends on two major processes—remineralization rates and sinking velocities. Here, we present an efficient method to measure sinking velocities of particles in the size range from approximately 3–400?μm by means of video microscopy (FlowCAM^?). The method allows rapid measurement and automated analysis of mixed samples and was tested with polystyrene beads, different phytoplankton species, and sediment trap material. Sinking velocities of polystyrene beads were close to theoretical values calculated from Stokes’ Law. Sinking velocities of the investigated phytoplankton species were in reasonable agreement with published literature values and sinking velocities of material collected in sediment trap increased with particle size. Temperature had a strong effect on sinking velocities due to its influence on seawater viscosity and density. An increase in 9?°C led to a measured increase in sinking velocities of ~40?%. According to this temperature effect, an average temperature increase in 2?°C as projected for the sea surface by the end of this century could increase sinking velocities by about 6?% which might have feedbacks on carbon export into the deep ocean.     

The therapeutic effect of Värska mud and Värska mineral water baths on the overuse pain and muscle tension syndromes in the working age population

Environmental Geochemistry and Health - The effects of bath therapy are complex and result from a unique interaction between the aquatic environment and the human body functions. The effect of bath...     

Vegetation dynamics on the Łeba Bar/Poland: a comparison of the vegetation in 1932 and 2006 with special regard to endangered habitats

Coastal dune ecosystems are among the most dynamic habitats with high conservation value in Europe but are also under strong anthropogenic pressure regarding coastal protection and recreation. Hence, it is of high importance to know about long-term natural and anthropogenic changes and development of protected dune habitats for nature conservation, as well as for coastal management. This paper aims to identify the vegetation dynamics on the Łeba Bar/Poland over a period of 74 years by cartometric comparison using modern Geographical Information System (GIS). To quantify the rate of vegetation dynamics two aerial photographs dating from 1932 and 2006 were digitalized and analyzed with GIS to produce digital vegetation maps. Information about decrease, increase and stability of vegetation types of this area are discussed. The results show that there has been a clear reduction in the total area of bare sand and a considerable increase of woodlands and dense grass communities. Nevertheless, the remaining extensive drift sand areas and deflation hollows on the Łeba Bar offer one of the most important habitats for pioneer vegetation on bare sand of migrating dunes and dunes at the Southern Baltic coast. The present work proved the need to observe the future development of the vegetation communities and to implement management measures to maintain the dynamic of this unique dune landscape.     

Hunted hunters? Effect of group size on predation risk and growth in the Australian subsocial crab spider Diaea ergandros

A reduced predation risk is considered to be a major adaptive advantage of sociality. While most studies are concerned with non-predatory prey species, group-living predators are likely to face similar threats from higher-order predators. We studied the relationship between group size and predation risk in the subsocial crab spider Diaea ergandros by testing predictions from theoretical models including attack abatement as well as the formation of protective retreats. In a field survey, we found predatory clubionid spiders in 35 % of the D. ergandros nests and as predicted, nest size did not correlate with predator presence. In a subsequent laboratory experiment, we observed survival probability, nest construction activity and feeding behaviour including weight development between groups of different sizes as well as in the absence or presence of a predator. Large groups had an advantage in terms of survival and growth compared to smaller groups or single individuals. They also built significantly larger nests than smaller groups, supporting the idea of protective retreat formation being an adaptive benefit to group living. Even though clubionids did attack D. ergandros, they did not significantly affect overall mortality of D. ergandros. The feeding experiment showed that spiders fed on a larger proportion of flies in the presence of a predator. However, these groups gained significantly less weight compared to the control groups, indicating that the potential predators not only act as predators but also as food competitors, constituting a twofold cost for D. ergandros.     

The synergistic effects of increasing temperature and CO2 levels on activity capacity and acid–base balance in the spider crab, Hyas araneus

With global climate change, ocean warming and acidification occur concomitantly. In this study, we tested the hypothesis that increasing CO₂ levels affect the acid–base balance and reduce the activity capacity of the Arctic spider crab Hyas araneus, especially at the limits of thermal tolerance. Crabs were acclimated to projected oceanic CO₂ levels for 12 days (today: 380, towards the year 2100: 750 and 1,120 and beyond: 3,000 μatm) and at two temperatures (1 and 4 °C). Effects of these treatments on the righting response (RR) were determined (1) at acclimation temperatures followed by (2) righting when exposed to an additional acute (15 min) heat stress at 12 °C. Prior to (resting) and after the consecutive stresses of combined righting activity and heat exposure, acid–base status and lactate contents were measured in the haemolymph. Under resting conditions, CO₂ caused a decrease in haemolymph pH and an increase in oxygen partial pressure. Despite some buffering via an accumulation of bicarbonate, the extracellular acidosis remained uncompensated at 1 °C, a trend exacerbated when animals were acclimated to 4 °C. The additional combined exposure to activity and heat had only a slight effect on blood gas and acid–base status. Righting activity in all crabs incubated at 1 and 4 °C was unaffected by elevated CO₂ levels or acute heat stress but was significantly reduced when both stressors acted synergistically. This impact was much stronger in the group acclimated at 1 °C where some individuals acclimated to high CO₂ levels stopped responding. Lactate only accumulated in the haemolymph after combined righting and heat stress. In the group acclimated to 1 °C, lactate content was highest under normocapnia and lowest at the highest CO₂ level in line with the finding that RR was largely reduced. In crabs acclimated to 4 °C, the RR was less affected by CO₂ such that activity caused lactate to increase with rising CO₂ levels. In line with the concept of oxygen and capacity limited thermal tolerance, all animals exposed to temperature extremes displayed a reduction in scope for performance, a trend exacerbated by increasing CO₂ levels. Additionally, the differences seen between cold- and warm-acclimated H. araneus after heat stress indicate that a small shift to higher acclimation temperatures also alleviates the response to temperature extremes, indicating a shift in the thermal tolerance window which reduces susceptibility to additional CO₂ exposure.     

Reproductive biology and population structure of the deep-sea hydrothermal vent worm Paralvinella grasslei (Polychaeta: Alvinellidae) at 13°N on the East Pacific Rise

Paralvinella grasslei is a polychaetous annelid living in the harsh, unstable and heterogeneous environmental conditions found at deep-sea hydrothermal vent sites in the eastern Pacific. The aim of this work was to examine the possible influence of the reproductive biology of P. grasslei on the structure of its populations. Maximum observed oocyte size inside the oviduct is 275 m, and fecundity is relatively low. Examination of gametes and young specimens suggested a direct benthic development for this species. The population structure of P. grasslei at 13°N/EPR (EPR=East Pacific Rise) revealed a discontinuous recruitment which seems to be synchronized within vent sites and fields. The data also suggested the occurrence of discrete breeding periods. P. grasslei probably reproduces several times a years, with an apparent periodicity. Tidal signals could be a possible cue for the coordination of the reproductive cycle. The life-history of P. grasslei is discussed in light of the reproductive biology of other terebellomorph polychaetes, and seems to be well adapted for colonizing the unstable environment of hot vents. Two main hypotheses can explain the dissemination processes of this species along axial oceanic ridges. The influence of nearbottom currents occurring along the central graben of the East Pacific Rise can be cosidered to account for part of the transport of larvae and juveniles, but the observations of polychaete erpochaetes on the test of hydrothermal bythograeid crabs and evidence that crab migrations occur between vents also support the possibility of zoochory for the dissemination of alvinellid polychaetes.     

Effect and its time lags of water level fluctuations in Three Gorges Reservoir on the macroinvertebrates in a tributary bay北大核心CSCD

In order to study how water level fluctuations (WLF) of reservoir influence the macroinvertebrate in tributary bay, we studied the effect of WLF of the Three Gorges Reservior on macroinvertebrate communities in Xiangxi Bay, and the time lags of such effect, based on the surveys in spring and summer from 2005 to 2010. In this research, WLF was represented by water level drawdown (WLD) and the sum of absolute values of rate of water level fluctuations (RWlf). Pearson correlation analysis was used to analyze the relationship between WLF and macroinvertebrates. No significant correlation was found between macroinvertebrates and sum of absolute values of RWLF, while WLD showed significant influence on some biotic parameters. In spring, WLD did not cause significant effect to macroinvertebrates (P > 0.05). In summer, however, the influence was significant, especially in the area of the downstream (XX01 - XX02) of the Xiangxi Bay (P < 0.05). The middle reach of the bay (XX05), located in the conjunction area between Xiangxi Bay and a secondary tributary of the TGR, was also affected significantly (P < 0.05). The relative abundance of Tubificidae declined with the increase of the WLF, while abundance of Chironomidae increased. The time lags of the influence to macroinvertebrates were about 15 days. This analysis indicated that WLF in the mainstream of the reservoir mainly influences the downstream of the tributary bay, and also affects the conjunction area of the secondary tributary. Chironomidae are more tolerant than Tubificidae in water-body with dramatic disturbance, therefore can be considered as the indicator of the effect of summer WLF on macroinvertebrates.     

The impact of unconfined mine tailings and anthropogenic pollution on a semi-arid environment – an initial study of the Rodalquilar mining district, south east Spain

A geochemical study of stream sediments near Rodalquilar (South-east Spain) was undertaken to investigate the impact of processing activities associated with nearby gold mining. Despite the semi-arid nature of the area, visual inspection of tailings indicates that considerable fluvial erosion occurs during rainfall events. Geochemical analysis demonstrates that Mo, Sb, Te, Bi and As are all found at elevated levels in stream sediments downstream of the tailings site. Elevated levels of Pb, Cu and Zn were also noted in stream sediments. Statistical analysis demonstrates that four factors control trace-element distribution. Factor 1 displays a strong association of Mo, Sb, Te and Bi and As and is attributed to the mine tailings. Factor 2 displays an association of Pb and Cu, and is most easily attributed to anthropogenic pollution. Factor 3 distinguishes Au and reflects the selective nature of ore-processing methods employed at the site. Factor 4 only highlights Zn, reflecting that it is derived from several, probably unrelated, sources.     

营养盐对海洋卡盾藻生长与产毒的影响（Effect of Some Nutrients on the Growth and Haemolytic Toxins Production of Chattonella marina）

海洋卡盾藻(Chattonella marina)是我国南方重要的有害赤潮原因种,其产生的溶血毒素、活性氧等可能是造成鱼类死亡的重要原因.在实验室条件下,研究了氮、磷和铁等营养盐对海洋卡盾藻生长及产毒的影响,以期为阐明海洋卡盾藻溶血毒素生成机制奠定基础.研究结果发现:在铁、氮、磷盐三因素四水平正交实验条件下,铁盐和氮盐是影响海洋卡盾藻生长的显著因子;氮盐和磷盐是影响海洋卡盾藻产毒的显著因子;铁盐浓度0.492mg·L-1、氮盐浓度375mg·L-1、磷盐浓度5mg·L-1时海洋卡盾藻的比生长速率最大;铁盐浓度0mg·L-1、氮盐浓度375mg·L-1、磷盐浓度0.5mg·L-1时海洋卡盾藻的产毒能力最强,即高氮、低磷条件下有利于海洋卡盾藻溶血毒素的合成.     

荧光法监测硝普钠释放NO过程及其对微藻生长的影响（Fluorescence Dynamic Monitoring of Nitric Oxide Release Process Following Administration of Sodium Nitroprusside and Its Effect on the Growth of Microalga）

以硝普钠(Sodium nitroprusside,SNP)为一氧化氮(Nitric oxide,NO)供体研究了NO对海洋微藻生长的影响.对不同浓度SNP在海水介质中释放NO的过程进行了监测;对所培养的亚心形扁藻(Platymonas subcordiformis)和中肋骨条藻(Skeletonema costatum)进行藻密度测定,观测NO对微藻生长的影响.结果表明:5、10和100μmol·L-1的SNP释放NO浓度大约分别为6×10-9、9×10-9和2×10-7mol·L-1左右,而释放时间分别为4、5.5和7.5h.研究表明,NO对不同微藻有明显不同的作用规律:NO持续作用下,对亚心形扁藻的最佳作用浓度在10-8mol·L-1数量级;对赤潮藻中肋骨条藻的最佳作用浓度在10-9mol·L-1数量级;赤潮藻对NO的响应比非赤潮藻更灵敏,NO可能是海洋生态系中微藻生长重要的调节因子.     

Impacts of temperature and acidification on larval calcium incorporation of the spider crab <Emphasis Type="Italic">Hyas araneus</Emphasis> from different latitudes (54° vs. 79°N)

The combined effects of ocean warming and acidification were compared in larvae from two populations of the cold-eurythermal spider crab Hyas araneus, from one of its southernmost populations (around Helgoland, southern North Sea, 54°N, habitat temperature 3–18°C; collection: January 2008, hatch: January–February 2008) and from one of its northernmost populations (Svalbard, North Atlantic, 79°N, habitat temperature 0–6°C; collection: July 2008, hatch: February–April 2009). Larvae were exposed to temperatures of 3, 9 and 15°C combined with present-day normocapnic (380 ppm CO₂) and projected future CO₂ concentrations (710 and 3,000 ppm CO₂). Calcium content of whole larvae was measured in freshly hatched Zoea I and after 3, 7 and 14 days during the Megalopa stage. Significant differences between Helgoland and Svalbard Megalopae were observed at all investigated temperatures and CO₂ conditions. Under 380 ppm CO₂, the calcium content increased with rising temperature and age of the larvae. At 3 and 9°C, Helgoland Megalopae accumulated more calcium than Svalbard Megalopae. Elevated CO₂ levels, especially 3,000 ppm, caused a reduction in larval calcium contents at 3 and 9°C in both populations. This effect set in early, at 710 ppm CO₂ only in Svalbard Megalopae at 9°C. Furthermore, at 3 and 9°C Megalopae from Helgoland replenished their calcium content to normocapnic levels and more rapidly than Svalbard Megalopae. However, Svalbard Megalopae displayed higher calcium contents under 3,000 ppm CO₂ at 15°C. The findings of a lower capacity for calcium incorporation in crab larvae living at the cold end of their distribution range suggests that they might be more sensitive to ocean acidification than those in temperate regions.