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311.
I.?Calderón Lucía?Pita S.?Brusciotti C.?Palacín X.?TuronEmail author 《Marine Biology》2012,159(1):187-197
Spatio-temporal variability in settlement and recruitment, high mortality during the first life-history stages, and selection
may determine the genetic structure of cohorts of long-lived marine invertebrates at small scales. We conducted a spatial
and temporal analysis of the common Mediterranean Sea urchin Paracentrotus
lividus to determine the genetic structure of cohorts at different scales. In Tossa de Mar (NW Mediterranean), recruitment was followed
over 5 consecutive springs (2006–2010). In spring 2008, recruits and two-year-old individuals were collected at 6 locations
along East and South Iberian coasts separated from 200 to over 1,100 km. All cohorts presented a high genetic diversity based
on a fragment of mtCOI. Our results showed a marked genetic homogeneity in the temporal monitoring and a low degree of spatial
structure in 2006. In 2008, coupled with an abnormality in the usual circulation patterns in the area, the genetic structure
of the southern populations studied changed markedly, with arrival of many private haplotypes. This fact highlights the importance
of point events in renewing the genetic makeup of populations, which can only be detected through analysis of the cohort structure
coupling temporal and spatial perspectives. 相似文献
312.
The Salí River Basin in north-west Argentina (7,000 km2) is composed of a sequence of Tertiary and Quaternary loess deposits, which have been substantially reworked by fluvial and
aeolian processes. As with other areas of the Chaco-Pampean Plain, groundwater in the basin suffers a range of chemical quality
problems, including arsenic (concentrations in the range of 12.2–1,660 μg L−1), fluoride (50–8,740 μg L−1), boron (34.0–9,550 μg L−1), vanadium (30.7–300 μg L−1) and uranium (0.03–125 μg L−1). Shallow groundwater (depths up to 15 m) has particularly high concentrations of these elements. Exceedances above WHO (2011) guideline values are 100% for As, 35% for B, 21% for U and 17% for F. Concentrations in deep (>200 m) and artesian groundwater
in the basin are also often high, though less extreme than at shallow depths. The waters are oxidizing, with often high bicarbonate
concentrations (50.0–1,260 mg L−1) and pH (6.28–9.24). The ultimate sources of these trace elements are the volcanic components of the loess deposits, although
sorption reactions involving secondary Al and Fe oxides also regulate the distribution and mobility of trace elements in the
aquifers. In addition, concentrations of chromium lie in range of 79.4–232 μg L−1 in shallow groundwater, 129–250 μg L−1 in deep groundwater and 110–218 μg L−1 in artesian groundwater. All exceed the WHO guideline value of 50 μg L−1. Their origin is likely to be predominantly geogenic, present as chromate in the ambient oxic and alkaline aquifer conditions. 相似文献
313.
Paola Rivaro Francisco Ardini Marco Grotti Giuseppe Aulicino Yuri Cotroneo Giannetta Fusco 《Chemistry and Ecology》2019,35(1):1-19
Dissolved iron (Fe) distribution and speciation was determined in water samples (0–200?m) collected in a coastal area near Terra Nova Bay during the austral summer of 2014. Nutrients, dissolved oxygen, chlorophyll-a, phytoplankton composition and prokaryotic biomass distribution were investigated in combination with measurements of the physical properties of the water columns and its dynamics. The dFe value was above the limiting growth concentration, ranging from 0.52 to 4.51?nM, and it showed a spatial variability with a horizontal length scale of about 10?km, according to the variability of the water column physical properties and to iron sources. The organic ligands (L) maintained the concentrations of dFe at levels much higher than the inorganic solubility of Fe, keeping it available for phytoplankton and the log K’FeL values found (from 22.1 to 23.6) highlighted the presence of complexes of differing stabilities. 相似文献
314.
315.
Sangiao-Alvarellos S. Guzmán J. M. Láiz-Carrión R. Míguez J. M. del Río M. P. Martín Mancera J. M. Soengas J. L. 《Marine Biology》2005,146(3):607-617
The influence of gonadal maturation on seawater adaptability at the metabolic level was assessed in the euryhaline teleost Sparus auratus by treatment of immature fish with 17ß-estradiol (E2) followed by acclimation to different environmental salinities. Fish were injected with coconut oil alone (sham) or containing E2 (10 µg g–1 body weight) and maintained in seawater (40). After 5 days, fish from oil- and E2-implanted groups were sampled. At the same time, fish of both groups were transferred to brackish water (5, hypoosmotic test), seawater (40, transfer test), and hypersaline water (55, hyperosmotic test); 4 days after transfer (9 days post-implant) all groups were sampled. Data obtained from liver suggest that E2 treatment produced effects comparable to those already reported in literature, including decreased glycogen levels, increased glycolytic potential, and decreased gluconeogenic potential. This, together with the fact that many changes displayed in shams among salinities disappeared in E2-treated fish allow us to suggest that the response of liver carbohydrate metabolism to osmotic acclimation is exceeded by the response elicited by E2 treatment. In gills, E2 treatment produced increased lactate levels, decreased capacity for use of exogenous glucose, and decreased the potential of the pentose phosphate pathway. These findings suggest that the energy demand occurring in gills during osmotic acclimation should be increasingly fuelled by substrates other than exogenous glucose. Finally, data obtained in brain of E2-treated fish suggest a lower necessity of exogenous glucose, increased lactate levels, and decreased glycolytic potential.Communicated by S.A. Poulet, Roscoff 相似文献
316.
Drinking water quality should remain constant from the drinking water treatment plant to the consumer's tap. However, water quality characteristics might be affected by interactions with pipe materials. This review describes the iron, copper, lead, zinc, aluminum, chromium, and cadmium in drinking water leached from the pipe material present in drinking water, as well as the factors and mechanisms that affect leaching processes. Data analysis suggests that monitoring the water quality in distribution systems is important for their proper management; however, the low measured concentrations highlight the need for sensitive sensors. In addition, further research is necessary to anticipate possible future effects before the installation of new materials/infrastructure or changes in water source/treatment. 相似文献
317.
Accumulation of metals by aquatic organisms is mostly affected by other biological components in environments. In this study, cadmium (Cd) accumulation in green algae, Cladophora glomerata (L.) Kutz., exposed to 0.1 and 1.0 mg L?1 of Cd for 15 and 30 days was examined in laboratory conditions in the presence of Nile tilapia Oreochromis niloticus (L.). The green algae C. glomerata accumulated Cd concentrations as 690 ± 70 and 3430 ± 470 mg kg?1 on day 15, and 1130 ± 180 and 6830 ± 1540 mg kg?1 on day 30. There were significant increases (p < 0.05) in metal accumulation by green algae as the exposure time and metal concentration increased. The results also indicated that the presence of Nile tilapia in the medium led to a significant Cd accumulation in the green algae compared to control (p < 0.05). 相似文献
318.
319.
Elie Gaget Diego Pavón-Jordán Alison Johnston Aleksi Lehikoinen Wesley M. Hochachka Brett K. Sandercock Alaaeldin Soultan Hichem Azafzaf Nadjiba Bendjedda Taulant Bino Luka Božič Preben Clausen Mohamed Dakki Koen Devos Cristi Domsa Vitor Encarnação Kiraz Erciyas-Yavuz Sándor Faragó Teresa Frost Clemence Gaudard Lívia Gosztonyi Fredrik Haas Menno Hornman Tom Langendoen Christina Ieronymidou Vasiliy A. Kostyushin Lesley J. Lewis Svein-Håkon Lorentsen Leho Luigujõe Włodzimierz Meissner Tibor Mikuska Blas Molina Zuzana Musilová Viktor Natykanets Jean-Yves Paquet Nicky Petkov Danae Portolou Jozef Ridzoň Samir Sayoud Marko Šćiban Laimonas Sniauksta Antra Stīpniece Nicolas Strebel Norbert Teufelbauer Goran Topić Danka Uzunova Andrej Vizi Johannes Wahl Marco Zenatello Jon E. Brommer 《Conservation biology》2021,35(3):834-845
Climate warming is driving changes in species distributions and community composition. Many species have a so-called climatic debt, that is, shifts in range lag behind shifts in temperature isoclines. Inside protected areas (PAs), community changes in response to climate warming can be facilitated by greater colonization rates by warm-dwelling species, but also mitigated by lowering extirpation rates of cold-dwelling species. An evaluation of the relative importance of colonization-extirpation processes is important to inform conservation strategies that aim for both climate debt reduction and species conservation. We assessed the colonization-extirpation dynamics involved in community changes in response to climate inside and outside PAs. To do so, we used 25 years of occurrence data of nonbreeding waterbirds in the western Palearctic (97 species, 7071 sites, 39 countries, 1993–2017). We used a community temperature index (CTI) framework based on species thermal affinities to investigate species turnover induced by temperature increase. We determined whether thermal community adjustment was associated with colonization by warm-dwelling species or extirpation of cold-dwelling species by modeling change in standard deviation of the CTI (CTISD). Using linear mixed-effects models, we investigated whether communities in PAs had lower climatic debt and different patterns of community change than communities outside PAs. For CTI and CTISD combined, communities inside PAs had more species, higher colonization, lower extirpation, and lower climatic debt (16%) than communities outside PAs. Thus, our results suggest that PAs facilitate 2 independent processes that shape community dynamics and maintain biodiversity. The community adjustment was, however, not sufficiently fast to keep pace with the large temperature increases in the central and northeastern western Palearctic. Our results underline the potential of combining CTI and CTISD metrics to improve understanding of the colonization-extirpation patterns driven by climate warming. 相似文献
320.
Assessment of patch quality by ladybirds: relative response to conspecific and heterospecific larval tracks a consequence of habitat similarity? 总被引:2,自引:0,他引:2
Alexandra Magro Joseph N. Téné Nicolas Bastin Anthony F. G. Dixon Jean-Louis Hemptinne 《Chemoecology》2007,17(1):37-45
Summary. Aphid colonies can reach high levels of abundance but last for short periods of time. The larvae of aphidophagous ladybirds
(Coleoptera: Coccinellidae) that feed on these colonies might therefore suffer from starvation, which favours the occurrence
of cannibalism and intraguild predation. Thus, the assessment of patch quality becomes crucial and it has been shown that
female ladybirds refrain from laying eggs in the presence of an oviposition deterring semiochemical deposited by their larvae.
Adalia bipunctata (L.), Adalia decempunctata (L.) and Coccinella septempunctata L. are 3 sympatric species of ladybirds, which can co-occur in aphid colonies. As a consequence, their eggs and larvae are
under threat, not only from cannibalism but also intraguild predation. Females should, therefore, also use the tracks deposited
by heterospecific larvae to assess the quality of aphid colonies as oviposition sites. The expectation is that: 1- the strength
of the reaction to each other’s larval tracks should be correlated with percentage habitat overlap and that 2- the reaction
to conspecific larval tracks should be stronger than to heterospecific tracks. In order to test these hypotheses, females’
oviposition behaviour was analysed and a chemical analysis of the tracks of their larvae undertaken.
The results show that oviposition behaviour is not related to habitat overlap. Both species of Adalia react to tracks of their own larvae and those of C. septempunctata, but A. decempunctata reacted more strongly than A. bipunctata. C. septempunctata reacted very slightly to its own tracks but not to those of either species of Adalia.
The larval tracks are mainly composed of alkanes. Those of the two species of Adalia are qualitatively 100% similar and 60% so when the quantitative results are compared. They are, however, only 24–29% similar
to those of Coccinella septempunctata. 相似文献