Diet and foraging of larvae of Somatochlora alpestris, an alpine dragonfly at its upper distribution limits (Odonata: Corduliidae)

PDF HTML阅读 XML下载 导出引用 引用提醒 普达措国家公园2个针叶树种径向生长对温度和降水的响应 DOI: 10.5846/stxb201710091794 作者: 作者单位: 西南林业大学,西南林业大学,西南林业大学,西南林业大学,云南碧塔海省级自然保护区管理局,云南碧塔海省级自然保护区管理局,云南碧塔海省级自然保护区管理局,西南林业大学 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学基金项目（31600395）；云南省教育厅科学研究基金项目（2015Z136，2017YJS094）；云南省高原湿地科学创新团队项目（2012HC007）；西南林业大学科技创新基金项目（C17139） Response of radial growth of two conifers to temperature and precipitation in Potatso National Park, Southwest China Author: Affiliation: Southwest Forestry University,Southwest Forestry University,Southwest Forestry University,Southwest Forestry University,,,,Southwest Forestry University Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:基于树轮年代学方法，利用普达措国家公园海拔上、下限丽江云杉（Picea likiangensis）和长苞冷杉（Abies georgei）树轮宽度资料，构建差值年表并分析其与温度和降水的关系，阐明影响该区域2个主要针叶树种径向生长的主要气候要素。结果表明：（1）海拔下限丽江云杉径向生长同时受到温度和降水的影响：与上年11月平均温、当年生长季后期（9-10月）平均温和上年7月降水呈显著正相关；（2）海拔上限丽江云杉径向生长只受温度影响，与上年生长季后期平均温呈显著负相关，与当年生长季盛期（6-8月）平均温呈显著正相关；（3）长苞冷杉径向生长只与温度表现出显著相关性，海拔下限的生长与上年11月平均温呈显著正相关，海拔上限的生长与当年生长季盛期平均温呈显著正相关。结果可为气候变化对滇西北高原树木生长影响研究提供参考，为滇西北高原森林生态系统管理与保护提供理论依据。 Abstract:The Hengduan Mountain is located to the southeastern margin of the Qinghai-Tibet Plateau, which is sensitive to climate change and a hot spot for tree-ring research; it has rich biodiversity and significant climate changes, so it plays an important role in climate change research. Up to now, tree-ring research in this area concentrated on the upper distributional limits, however the systematic study of both the upper and lower distributional limits was out of focus. Based on the dendrochronological method, we established the residual chronologies of Picea likiangensis and Abies georgei at their upper and lower distributional limits by using tree-ring width data, and studied the relationship between the residual chronologies, temperature and precipitation. The study can identify the key climatic factors that affect the radial growth of two conifers. The results showed that:(1) The radial growth of Picea likiangensis was affected by both temperature and precipitation at its lower limits; there were significant and positive correlations between its growth and November mean temperature (Tmean) in the previous year, Tmean of post growing season (September-October) in the current year and July precipitation in previous year. (2) The radial growth of Picea likiangensis was only affected by temperature at its upper limits, by showing a negative correlation with Tmean of post growing season in the previous year, and a significantly positive correlation with Tmean of growing season (June-August) in the current year. (3) The radial growth of Abies georgei was only correlated with temperature. November Tmean in the previous year and growing season Tmean in the current year positively affected its growth at lower and upper distributional limits respectively. The results of this paper can offer a reference for the study in effects of climate change on tree growth in Northwest Yunnan Plateau, and provide a theoretical basis for the management and protection of forest ecosystems in the area. 参考文献 相似文献 引证文献

Species' life history traits, such as fecundity, and how they co‐vary with other traits are central to models in population and community ecology. Within species, increasing fecundity with body size is often driven by nutritional quality of the diet. How and why fecundity varies among species is poorly understood but likely to be related, at least in part, to patterns of resource acquisition and allocation. This study tested for an interspecific, fecundity–size relationship among caddisfly species and tested whether fecundity covaried with larval diet. Data on fecundity and body size were collated for 102 species in 75 genera and 28 families from around the world. Species were assigned to one of four categories of larval diet (algivores, detritivores, filter‐feeders, predators) and also two combined diet groups, differentiated by the prevalence of animal versus plant material. A limiting relationship best described the positive association between fecundity and body size of all caddisflies, where size set an upper limit to fecundity. Diet explained variation below the upper limit. Compared to species with plant‐based diets, consumers of animal material had higher fecundity and diet‐specific fecundity–size relationships with steeper slopes. All relationships were hypoallometric (slopes less than 1), indicating a disproportionate effect of size on fecundity: in each diet group, large‐bodied species produced absolutely more, but proportionately fewer eggs than smaller‐bodied species, suggesting size‐related shifts in resource allocation. The largest species were detritivores, which is consistent with the Jarman–Bell principle that large animals are likely to have nutritionally poor diets. These diet‐related patterns in fecundity may lead to diet‐related patterns in population dynamics among species within freshwater communities that have not been considered previously.

The allocation of nutritional resources to reproduction in animals is a complex process of great evolutionary significance. We use compound-specific stable isotope analysis of carbon (GC/combustion/isotope ratio MS) to investigate the dietary sources of egg amino acids in a nectar-feeding hawkmoth. Previous work suggests that the nutrients used in egg manufacture fall into two classes: those that are increasingly synthesized from adult dietary sugar over a female's lifetime (renewable resources), and those that remain exclusively larval in origin (nonrenewable resources). We predict that nonessential and essential amino acids correspond to these nutrient classes and test this prediction by analyzing egg amino acids from females fed isotopically distinct diets as larvae and as adults. The results demonstrate that essential egg amino acids originate entirely from the larval diet. In contrast, nonessential egg amino acids were increasingly synthesized from adult dietary sugars, following a turnover pattern across a female's lifetime. This study demonstrates that female Lepidoptera can synthesize a large fraction of egg amino acids from nectar sugars, using endogenous sources of nitrogen. However, essential amino acids derive only from the larval diet, placing an upper limit on the use of adult dietary resources to enhance reproductive success.

MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsTheme Sections MEPS 125:117-126 (1995) - doi:10.3354/meps125117 Factors controlling the upper and lower limits of the intertidal distribution of two Corophium species in the Wadden Sea Beukema JJ, Flach EC On the tidal flats of the Dutch Wadden Sea, high densities of Corophium volutator (in silty areas) and of C. arenarium (in sandy areas) were limited to the upper parts of the intertidal zone. The upper limit was always situated close to the local level of high water at neap tides. After periods of higher- or lower-than-average water levels (caused by prevailing westerly or easterly winds, respectively), the zone of Corophium volutator distribution had shifted upward or downward, respectively. Conversely, the lower limits of high Corophium spp.densities did not show a consistent relation with intertidal level or duration of immersion but coincided with the upper level of high (&GT10 m-2) densities of adult lugworms Arenicola marina. In areas with sandy sediments (silt content &LT ca 15%), this limit was situated about halfway between mean high water and mean tide level. In more muddy sediments, lugworms were scarce and high C. volutator densities extended to lower intertidal levels. It is concluded that zonation in the soft-bottom intertidal may generally be governed by the same processes as are prevalent in the rocky intertidal, viz. abiotic factors setting the upper limits and biotic interrelations setting the lower limits of species. Intertidal zonation . Limiting factors . Water level . Species interactions . Corophium Full text in pdf format PreviousNextExport citation RSS - Facebook - Tweet - linkedIn Cited by Published in MEPS Vol. 125. Publication date: September 14, 1995 Print ISSN:0171-8630; Online ISSN:1616-1599 Copyright © 1995 Inter-Research.

Plant height decreases much within narrow altitudinal spans near treelines. We compared the stem age, stem inclination and shoot elongation rates of alpine dwarf pine Pinus pumila between the upper distribution limit (treeline, 2,850 m a.s.l.) and the lower distribution limit (2,500 m a.s.l.) on Mount Norikura in central Japan, to examine how the growth traits of P. pumila change with altitude. The mean stem height at the upper distribution limit (49 cm) was about a quarter of that at the lower distribution limit (187 cm). The mean ratio of stem height to length was lower at the upper distribution limit than at the lower distribution limit, indicating that P. pumila stems inclined more at the higher altitude. The mean stem age at the upper distribution limit (48 years) was less than a half of that at the lower distribution limit (109 years). Although the shoot elongation rate positively correlated with stem length at the two altitudes, the shoot elongation rate at a given stem length was lower at the upper distribution limit than at the lower distribution limit. Thus, less developed scrub at the upper distribution limit than at the lower distribution limit was due to shorter stem age, more creeping stems and lower shoot elongation rates. Generally, wind velocity is greater in higher altitudes. Probably, strong wind reduces the growth and mean stem age of P. pumila stems at the upper distribution limit. Therefore, this study concludes that the scrub height of P. pumila is controlled not only by temperature, but also by strong wind.

Physical rather than biotic factors set the lower limit of mussel beds in a horizontal rocky intertidal platform

ABSTRACTPrediction limits for Poisson distribution are useful in real life when predicting the occurrences of some phenomena, for example, the number of infections from a disease per year among school children, or the number of hospitalizations per year among patients with cardiovascular disease. In order to allocate the right resources and to estimate the associated cost, one would want to know the worst (i.e., an upper limit) and the best (i.e., the lower limit) scenarios. Under the Poisson distribution, we construct the optimal frequentist and Bayesian prediction limits, and assess frequentist properties of the Bayesian prediction limits. We show that Bayesian upper prediction limit derived from uniform prior distribution and Bayesian lower prediction limit derived from modified Jeffreys non informative prior coincide with their respective frequentist limits. This is not the case for the Bayesian lower prediction limit derived from a uniform prior and the Bayesian upper prediction limit derived from a modified Jeffreys prior distribution. Furthermore, it is shown that not all Bayesian prediction limits derived from a proper prior can be interpreted in a frequentist context. Using a counterexample, we state a sufficient condition and show that Bayesian prediction limits derived from proper priors satisfying our condition cannot be interpreted in a frequentist context. Analysis of simulated data and data on Atlantic tropical storm occurrences are presented.

Temperature is a critical environmental factor determining the upper limits of evergreen broadleaved tree taxa. However, whether carbon source or carbon sink limitation shapes this limit is not yet fully understood. We studied a subtropical evergreen oak (Cyclobalanopsis gracilis) at the northern limit of its distributional range. Along an elevational/temperature gradient towards its upper limit, we surveyed the variations in non-structural carbohydrate (NSC) concentrations of C. gracilis adults for 3 years. Additionally, a carbon balance manipulation experiment of debudding and defoliation was done to C. gracilis seedlings close to the upper distributional limit, aiming at investigating the changes in NSC concentrations and growth rates in different treatment groups. Our results showed that increasing elevation or decreasing temperature did not affect the trends of NSC concentration in twigs, old branches, or trunks of adults, nor did carbon balance manipulations (debudding or defoliation) of seedlings have a significant effect on the growth, while defoliation decreased NSC concentration in twigs. These results suggest that carbon sink limitation is the key physiological mechanism underlying low temperature in the shaping of this dominant evergreen broadleaved tree species in eastern China. Therefore, the formation of upper limits in evergreen oaks is most likely the result of a direct low-temperature restriction on meristematic activity and tissue formation instead of the result of insufficient carbon supply. More studies with expanded sample sizes are needed on other evergreen broadleaved tree species growing at their upper limits to confirm the carbon sink limitation hypothesis and reveal the detailed mechanisms.

The limits of stratigraphic distribution of Glossopteris in India

Event Abstract Back to Event Patterns of the vertical distribution limits of the limpet Patella depressa on the Portuguese coast Daniela Nobre1*, Maria I. Seabra1 and Teresa Cruz1, 2 1 Centro de Ciências do Mar e do Ambiente (MARE), Portugal 2 Departamento de Biologia, Escola de Ciências e Tecnologia, Universidade de Évora, Portugal The limpet Patella depressa is a keystone species in the rocky shores of the Northeast Atlantic. Vertical distribution limits may vary spatially and temporally due to different physical and biological factors. The spatial variation on the intertidal limits of the distribution of P. depressa, as well as on the abundance of this species, was studied during the winter of 2012, in three shores (two in the north - Moledo and Gelfa - and one in the southwest - Oliveirinha - coast of Portugal). In each shore, three transects across the vertical intertidal gradient were considered; within each transect, we measured the shore height at the lower and the upper limits of P. depressa distribution (defined by the position of the last individual found in the lower and upper extremes along the transect), as well as the horizontal extension (the distance along the rock surface) between those two limits. Densities of two size classes (<2 cm and > 2 cm of maximum shell length – MSL) of limpets in 0.25 m2 were assessed in the area of the species’ greatest abundance within the same transects (n = 6 replicates). Spatial variation of the in situ temperature at the lower and the upper limits of distribution was also analyzed by deploying limpet-biomimetic sensors at both limits in all shores and transects, recording semi-continuous temperature every 15 minutes. Furthermore, the temporal variation on the shore height of the vertical distribution limits was studied in Oliveirinha in two dates (March and July 2014) along seven to ten transects, by comparing the marked locations of each limit (the position of the last individual found in the lower and upper extremes along each transect) between dates. Overall, the height of the lower limit did not vary among shores, whereas the upper limit was, on average, one meter lower in Oliveirinha compared to Moledo and Gelfa. Total abundance was four times higher in the shores of the north coast, although the density of larger limpets (> 2 cm MSL) was twenty times higher in Oliveirinha. In all shores, temperature was more variable on the upper limits than on the lower limits, and the daily minimum temperature at both limits was consistently lower in Oliveirinha when comparing with the northern shores. Regarding temporal variation in Oliveirinha, although the average height of both lower and upper limits did not differ between dates, we found significant differences between dates in the relative direction of the change in individual positions marked for each limit, with a consistent decrease of both limits in July relatively to March. Keywords: Patella depressa, vertical distribution, temperature, abundance, limpets Conference: IMMR'18 | International Meeting on Marine Research 2018, Peniche, Portugal, 5 Jul - 6 Jul, 2018. Presentation Type: Poster Presentation Topic: Biodiversity, Conservation and Coastal Management Citation: Nobre D, Seabra MI and Cruz T (2019). Patterns of the vertical distribution limits of the limpet Patella depressa on the Portuguese coast. Front. Mar. Sci. Conference Abstract: IMMR'18 | International Meeting on Marine Research 2018. doi: 10.3389/conf.FMARS.2018.06.00051 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 27 Apr 2018; Published Online: 07 Jan 2019. * Correspondence: Ms. Daniela Nobre, Centro de Ciências do Mar e do Ambiente (MARE), Lisbon, Portugal, daniela.nobre.silva@hotmail.com Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Daniela Nobre Maria I Seabra Teresa Cruz Google Daniela Nobre Maria I Seabra Teresa Cruz Google Scholar Daniela Nobre Maria I Seabra Teresa Cruz PubMed Daniela Nobre Maria I Seabra Teresa Cruz Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

Living Nummulitidae achieve their highest diversity in the subtropical and tropical West Pacific. Although all house symbiotic microalgae, they avoid highly illuminated areas near the water surface, since their flat tests could be easily damaged by the hydrodynamic regime. The preference for calm water conditions extends their depth distribution down to the base of the photic zone. West Pacific Nummulitidae can be differentiated into ten species belonging to six genera according to an ecological species concept. The genus Operculina d’Orbigny is represented by three species. While O. discoidalis (d’Orbigny) prefers a fine-grained bottom under medium light conditions (10% surface intensity), O. ammonoides (Gronovius) prefers a coarser substrate and sometimes can be found on hard bottoms. Light dependence ranges from 1.5% to 68% surface intensity. Less illuminated coarse sands are inhabited by Operculina cf. O. complanata (Defrance), which is the dominant symbiont-bearing foraminifer between light intensities of 0.2% to 12% surface illumination. The genus Planostegina Banner and Hodgkinson demonstrates transitions to the genus Operculina in test form and surface, while the division into chamberlets is similar to Heterostegina. Planostegina operculinoides (Hofker) is distinguished by flat tests and delicate chamberlets. It lives on sandy bottoms restricted to light intensities between 0.45% and 26% surface illumination. The more robust Planstegina aff. P. operculinoides (Hofker) prefers light intensities between 0.4% and 2.7% surface illumination. Planoperculina heterosteginoides (Hofker) shows morphological transition to Operculina cf. O. complanata in developing incomplete septula. This species lives in low illuminated areas (0.3% to 2.5% surface intensity) and prefers medium to fine-grained sands. Heterostegina depressa d’Orbigny spans a broad range in light intensities (2% to 70% surface illumination), and is protected against irradiation by thick tests and a cryptic life mode near the surface. Test construction enables life under strong hydrodynamic regimes. This species lives firmly attached to hard substrates, thus counteracting transportation by water movement. Nummulites venosus (Fichtel and Moll) differs from H. depressa in having undivided chambers. It lives exclusively on coarse sand and avoids high sediment movement, thus starting its distribution beneath the fair weather wave base. According to light intensities, the upper limit may be similar to O. ammonoides (80%), while the lower limit is 2.5% surface illumination. Operculinella cumingii (Carpenter) inhabits coarse to medium sand in deeper regions between 1.2% and 25% surface illumination. Tests of the cyclic, large-sized species Cycloclypeus carpenteri Brady are easily transported due to the thin, plate-like form. The upper distribution limit correlates with the storm wave base, restricting C. carpenteri to depths below 50 m. The lower distribution limit depends on light intensity and is located near the base of the photic zone (0.4% surface illumination).

The distribution of the lucidophyllous forest and its transition to the summergreen broadleaf forest were studied in relation to such environmental factors as temperature and precipitation. The distribution is primarily affected by low temperatures during winter and secondarily by precipitation and sea wind. The upper and northern limits of the forest most closely correlated with the coldness index within four thermal indices. Because of much snow, the forest is more suppressed at a lower altitude in the region with high snowfall than in other regions. The area at its upper limit is dominated by the evergreenQuercus forest while the area at its northern limit is occupied by thePersea forest. Moreover, CI values in these distributional limits are significantly different. This phenomenon appeared to result from the resistance ability of dominant lucidophyllous trees not only to the thermal conditions but also to sea wind. In both the region with high snowfall and the region with high rainfall there is a zone where the evergreenQuercus forest overlaps theFagus crenata forest. In contrast, in the region with little rainfall, these two forests do not overlap but form a gap dominated by forests such as theFagus japonica forest. Thus, precipitation factors largely affect the altitudinal forest zones in Japan.

Distribution of hadal genera depends on the lower limits of their bathymetrical ranges

Nonstructural carbohydrate (NSC) concentration in plant organs is an indicator of a balance between carbon sources (i.e., photosynthesis) and sinks (i.e., growth). Understanding how NSC concentrations change with altitude would help determine altitudinal changes in plant growth. This study compared shoot growth and seasonal changes in NSC concentrations of current-year and 1-year-old needles and branch woods between the upper and lower distribution limits of subalpine conifers Abies veitchii (1600–2000 m a.s.l.), A. mariesii (2000–2400 m a.s.l.), and Pinus pumila (2400–2800 m a.s.l.) in Japan. The lengths of 1-year-old shoots were shorter at the upper distribution limits for the three species, and concentrations and branch woods were all high in spring but decreased toward summer, increasing from summer to autumn. No clear difference was found for either parameter between upper and lower distribution limits for each species. Therefore, this study suggests that growth reduction at the upper distribution limits is due to reduction of both sink and source activities, with similar degrees for each species. However, further studies of sink and source activities, such as temperature-dependent photosynthesis and growth traits, are necessary to reveal clearly the cause of this growth reduction in high altitudes.

Low temperature is a major driver of the upper distributional limits of subtropical evergreen broadleaved forests in East Asia. The eco‐physiology of evergreen broadleaved trees at the upper limits could respond to both lower winter temperature and lower averaged annual temperature that covary with elevation. To analyze these responses, we assessed the variations in leaf chemical traits of Cyclobalanopsis gracilis with seasonality and along elevation in the ecotone from subtropical to temperate climate, and analyzed the relationships between traits of mature leaves and temperature. The study showed that the mass‐based nonstructural carbohydrate (NSC) content reached the highest level across elevations during winter; however, the winter NSC content did not differ between elevations. For mature leaves, leaf dry mass per area (LMA) tended to be higher approaching the upper limit. The leaf carbon to phosphorus ratio (C/P) showed an increasing trend with decreasing temperature, as did leaf carbon to nitrogen ratio (C/N) to some extent. The mass‐based P content showed a decreasing trend approaching the upper limit, whereas area‐based P content showed no significant variation. Our main results indicate that leaf NSC content is highest at all elevations in winter, and individuals at high elevations have high LMA and high nutrient use efficiency. The results suggest that for C. gracilis, an increasing leaf NSC results in a baseline protection to cope with cold in winter, which, at higher elevations is supplemented with increasing LMA and nutrient use efficiency to cope with associated low‐temperature stress.