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1.
Amy S. Commendador John V. Dudgeon Bruce P. Finney Benjamin T. Fuller Kelley S. Esh 《American journal of physical anthropology》2013,152(2):173-185
Ecological and environmental evidence suggests that Rapa Nui was among the most marginally habitable islands in Eastern Polynesia, with only a fraction of the biotic diversity found on archipelagos to the west, and capable of sustaining many fewer cultigens traditionally transported by Polynesian colonizers. However, archaeological evidence for human dietary adaptations under such restrictions is limited. Little is known about the particulars of the subsistence base and dietary changes on Rapa Nui that may be associated with a hypothesized late prehistoric decline in the quality and diversity of food sources. To better understand prehistoric Rapa Nui diet we examined stable carbon and nitrogen isotope compositions of human teeth along with archaeological faunal material thought to comprise the Rapa Nui food web. Our results indicate that contrary to previous zooarchaeological studies diet was predominantly terrestrial throughout the entire sequence of occupation, with reliance on rats, chickens and C3 plants. While a few individuals may have had access to higher trophic level marine resources, this is evident only later in time (generally post–AD 1600). A decline in δ15N through time was observed, and may be attributed to declines in available terrestrial proteins; however, presently we cannot rule out the effect of changing soil and plant baseline δ15N. Our results also suggest differential access to higher trophic level marine resources among contemporaneous populations, but more research is required to clarify this observation. Am J Phys Anthropol 152:173–185, 2013. © 2013 Wiley Periodicals, Inc. 相似文献
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Using radiocarbon to determine the mycorrhizal status of fungi 总被引：7，自引：3，他引：7
Erik A. Hobbie Nancy S. Weber James M. Trappe Gert J. van Klinken 《The New phytologist》2002,156(1):129-136
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In this research, carbon and nitrogen stable isotopes in human bones dating from the Spring and Autumn periods were analyzed from the Sunjianantou site, Fengxiang, Shaanxi Province. All samples were well preserved and could be clearly used as dietary indicators. During these periods, the ancient Qin peoples' diet mainly relied on C4 plants and some meat, based on the comprehensive analysis of δ13C and δ15N values. From this analysis, we suggest that the substance strategy was a mixture of agriculture and herding. According to the comparative analysis of δ13C and δ15 N values, the human as funerary objects probably represent concubines or attendants whose diet was similar to their owners. Obviously the diet of Qin ancestors was stable from Spring and Autumn period through to the Warring States period, and any change in the proportions of C4 and value of δ15 N were related to the historical transition of the society. 相似文献
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T L Dupras H P Schwarcz S I Fairgrieve 《American journal of physical anthropology》2001,115(3):204-212
Current knowledge of infant feeding and weaning practices during the Roman period in Egypt is limited to scanty documentary and iconographic evidence. Stable nitrogen and carbon isotope analysis provides another avenue to explore this question. A sample of 49 infant and juvenile human skeletal remains from the Kellis 2 cemetery in the Dakhleh Oasis, Egypt, was used to determine patterns of infant feeding and weaning. delta(15)N values indicate that supplementary foods were introduced at around 6 months of age, and that weaning was complete by 3 years of age. By 6 months of age, delta(13)C values become increasingly enriched over adult values, and reach peak enrichment at approximately 1.5 years of age. Beyond this age, delta(13)C gradually declines to approach adult values. This enrichment in infant delta(13)C values is indicative of consumption of (13)C-enriched supplementary foods. Based on isotopic study of faunal and botanical remains from the ancient village of Kellis, we conclude that at approximately 6 months of age, infants were fed milk of goat and/or cow. 相似文献
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本文对陕西凤翔孙家南头秦墓出土的春秋战国时期人骨中C和N稳定同位素组成进行了测试分析。结果表明: 人骨样品均可用于食谱分析; 由δ13C和δ15N值综合分析可知, 春秋战国时期陕西凤翔地区秦先民是以C4类植物为主食、辅以少量肉食的杂食性食谱; 经济模式可能为农业与畜牧兼营, 以种植黍、粟类等旱地作物的农业形式为主, 并辅以驯养牲畜; 根据墓主与殉人的δ13C和δ15N值对比分析, 推测殉人可能是与墓主饮食方式较为相近的姬妾或仆从之类的人;春 秋中期至战国晚期秦先民的食物结构较为稳定, C4植物比例与δ15N发生变化的原因可能与当时历史的变迁与社会的发展有一定的关系。 相似文献
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Soichiro Kusaka Yasuhiro Yamada Minoru Yoneda 《American journal of physical anthropology》2018,167(2):377-388
Objectives
Holocene hunter‐gatherers adapted to climatic and environmental changes over time. Carbon and nitrogen stable isotope analysis of human skeletal remains from the Inariyama shell mound of the Final Jomon period have revealed large dietary variations in the population. This study analyzed radiocarbon dates of these individuals to test temporal changes in diet and its relationship with tooth ablation.Materials and Methods
Twenty‐nine human skeletal remains from Inariyama were included in this study. Extracted bone collagen samples were purified to graphite. Then, radiocarbon dating of these samples was performed using the accelerator mass spectrometer.Results
The radiocarbon ages of Inariyama ranged about, 3,230–2,140 cal BP and showed three peaks of occupation. In the early and late phases, terrestrial resource consumption and incisor extraction were observed, while marine resource consumption and canine extraction were observed in the middle phase.Discussion
These temporal changes of diet and tooth ablation types occurred in parallel with climatic cooling and environmental change and help reveal how Holocene hunter‐gatherers adapted to the changing environments.8.
通过测定青藏高原东部高寒区不同海拔主要植物和消费者种群（雀形目鸟类和小型哺乳类）的稳定碳、氮同位素比值,研究了高寒草甸消费者种群同位素组成特征及其影响因素。结果表明：植物平均稳定碳同位素随海拔升高表现出明显的增加趋势;消费者种群稳定碳、氮同位素随海拔的升高有明显的富集效应。雀形目鸟类种群稳定碳、氮同位素随海拔的升高均呈明显增加趋势;小型哺乳类稳定碳同位素随海拔上升不明显,而稳定氮同位素具有明显的增大趋势。消费者种群稳定碳、氮同位素沿海拔梯度的富集效应,一方面与植物稳定同位素在海拔梯度上的富集密切相关;另一方面与海拔和纬度变化所引起一系列环境因子的变化在一定程度上影响到动物的稳定同位素分布模式。另外,在高寒草甸地区,与雀形目鸟类相比,小型哺乳类在动物稳定同位素组成的代谢过程中更容易受到环境改变的影响。 相似文献
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Food is well-known to encode social and cultural values, for example different social groups use different consumption patterns to act as social boundaries. When societies and cultures change, whether through drift, through population replacement or other factors, diet may also alter despite unchanging resource availability within a region. This study investigates the extent to which dietary change coincides with cultural change, to understand the effects of large-scale migrations on the populations' diets. Through stable carbon and nitrogen isotope analysis of Iron Age, Roman, and Early Medieval human bone collagen, we show that in Croatia large-scale cultural change led to significant changes in diet. The isotopic evidence indicates that Iron Age diet consisted of C(3) foodstuffs with no isotopic evidence for the consumption of C(4) or marine resources. With the Roman conquest, marine resources were added to the diet, although C(3) foodstuffs continued to play an important role. In the Early Medieval period, this marine component was lost and varying amounts of C(4) foodstuffs, probably millet, were added to the otherwise C(3) diet. In both of these transitions it is likely that the changes in diet are related to the arrival of a new people into the area. 相似文献
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Mosses are the dominant plants in polar and boreal regions, areas which are experiencing rapid impacts of regional warming. Long‐term monitoring programmes provide some records of the rate of recent climate change, but moss peat banks contain an unrivalled temporal record of past climate change on terrestrial plant Antarctic systems. We summarise the current understanding of climatic proxies and determinants of moss growth for contrasting continental and maritime Antarctic regions, as informed by 13C and 18O signals in organic material. Rates of moss accumulation are more than three times higher in the maritime Antarctic than continental Antarctica with growing season length being a critical determinant of growth rate, and high carbon isotope discrimination values reflecting optimal hydration conditions. Correlation plots of 13C and 18O values show that species (Chorisodontium aciphyllum / Polytrichum strictum) and growth form (hummock / bank) are the major determinants of measured isotope ratios. The interplay between moss growth form, photosynthetic physiology, water status and isotope composition are compared with developments of secondary proxies, such as chlorophyll fluorescence. These approaches provide a framework to consider the potential impact of climate change on terrestrial Antarctic habitats as well as having implications for future studies of temperate, boreal and Arctic peatlands. There are many urgent ecological and environmental problems in the Arctic related to mosses in a changing climate, but the geographical ranges of species and life‐forms are difficult to track individually. Our goal was to translate what we have learned from the more simple systems in Antarctica, for application to Arctic habitats. 相似文献
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Carolina Trochine Marcelo Guerrieri Lone Liboriussen Priscila Willems Torben L. Lauridsen Martin Søndergaard Erik Jeppesen 《Freshwater Biology》2017,62(9):1596-1613
- Carbon (C) and nitrogen (N) stable isotope composition (15N:14N, δ15N and 13C:12C, δ13C) have been widely used to elucidate changes in aquatic ecosystem dynamics created by eutrophication and climate warming, often, however, without accounting for seasonal variation.
- Here, we aim to determine the factors controlling the stable isotope composition and C:N ratio of seston and periphyton in shallow lakes with contrasting nutrient loadings and climate; for this purpose, we followed the monthly stable isotope composition (c. 1 year) of seston (SES) and periphyton (PER) in 24 mesocosms mimicking shallow lakes with two nutrient treatments (enriched and unenriched) and three temperature scenarios (ambient, +3 and +5°C).
- Nutrient enrichment and warming had a stronger impact on the δ15N and δ13C values of seston than on periphyton, and the temporal isotopic variability in both communities was large.
- δ15NPER did not differ markedly between nutrient treatments, whereas δ15NSES was lower in the enriched mesocosms, possibly reflecting higher N2‐fixation by cyanobacteria. δ15NSES was higher in winter in the heated mesocosms and its dynamics was linked with that of NH4‐N, whereas δ15NPER showed a stronger association with NO3‐N. δ15NSES demonstrated a positive relationship with mean monthly temperature, indicating less isotope fractionation among autotrophs when production increased.
- δ13CSES was lowest in the enriched mesocosms during winter, whereas δ13CPER did not differ between nutrient treatments. δ13CSES and δ13CPER were positively related to pH, likely reflecting a pH‐induced differential access to dissolved carbon species in the primary producers. The positive δ13C‐temperature relationship suggested less fractionation of CO2 and HCO3? and/or larger use of HCO3? at higher temperatures.
- The C:N ratios varied seasonally and the differences between the enriched and unenriched mesocosms were stronger for seston than for periphyton. Particularly, the C:NSES ratios did not indicate deficiencies in N as opposed to the C:NPER ratios, supporting the observed changes in δ15N and suggesting that seston and periphyton have access to different sources of nutrients. We did not observe any clear effect of temperature warming on the C:N ratios.
- Our study provides evidence of strong seasonality in the isotopic composition and C:N ratios of seston and periphyton across nutrient and temperature levels; also, we identified several factors that are likely to modulate the strength and variability in stable isotopes values and stoichiometry of sestonic and periphytic communities under these scenarios.
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Karyn C. Olsen Christine D. White Fred J. Longstaffe Kristin von Heyking George McGlynn Gisela Grupe Frank J. Rühli 《American journal of physical anthropology》2014,153(4):598-604
Paleodiet research traditionally interprets differences in collagen isotopic compositions (δ13C, δ15N) as indicators of dietary distinction even though physiological processes likely play some role in creating variation. This research investigates the degree to which bone collagen δ13C and δ15N values normally vary within the skeleton and examines the influence of several diseases common to ancient populations on these isotopic compositions. The samples derive from two medieval German cemeteries and one Swiss reference collection and include examples of metabolic disease (rickets/osteomalacia), degenerative joint disease (osteoarthritis), trauma (fracture), infection (osteomyelitis), and inflammation (periostitis). A separate subset of visibly nonpathological skeletal elements from the German collections established normal intraindividual variation. For each disease type, tests compared bone lesion samples to those near and distant to the lesions sites. Results show that normal (nonpathological) skeletons exhibit limited intraskeletal variation in carbon‐ and nitrogen‐isotope ratios, suggesting that sampling of distinct elements is appropriate for paleodiet studies. In contrast, individuals with osteomyelitis, healed fractures, and osteoarthritis exhibit significant intraskeletal differences in isotope values, depending on whether one is comparing lesions to near or to distant sites. Skeletons with periostitis result in significant intraskeletal differences in nitrogen isotope values only, while those with rickets/osteomalacia do not exhibit significant intraskeletal differences. Based on these results, we suggest that paleodiet researchers avoid sampling collagen at or close to lesion sites because the isotope values may be reflecting both altered metabolic processes and differences in diet relative to others in the population. Am J Phys Anthropol 153:598–604, 2014. © 2013 Wiley Periodicals, Inc. 相似文献
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Eric W. Slessarev Erin E. Nuccio Karis J. McFarlane Christina E. Ramon Malay Saha Mary K. Firestone Jennifer Pett‐Ridge 《Global Change Biology Bioenergy》2020,12(10):834-847
Perennial bioenergy crops have been shown to increase soil organic carbon (SOC) stocks, potentially offsetting anthropogenic C emissions. The effects of perennial bioenergy crops on SOC are typically assessed at shallow depths (<30 cm), but the deep root systems of these crops may also have substantial effects on SOC stocks at greater depths. We hypothesized that deep (>30 cm) SOC stocks would be greater under bioenergy crops relative to stocks under shallow‐rooted conventional crop cover. To test this, we sampled soils to between 1‐ and 3‐m depth at three sites in Oklahoma with 10‐ to 20‐year‐old switchgrass (Panicum virgatum) stands, and collected paired samples from nearby fields cultivated with shallow rooted annual crops. We measured root biomass, total organic C, 14C, 13C, and other soil properties in three replicate soil cores in each field and used a mixing model to estimate the proportion of recently fixed C under switchgrass based on 14C. The subsoil C stock under switchgrass (defined over 500–1500 kg/m2 equivalent soil mass, approximately 30–100 cm depth) exceeded the subsoil stock in neighboring fields by 1.5 kg C/m2 at a sandy loam site, 0.6 kg C/m2 at a site with loam soils, and showed no significant difference at a third site with clay soils. Using the mixing model, we estimated that additional SOC introduced after switchgrass cultivation comprised 31% of the subsoil C stock at the sandy loam site, 22% at the loam site, and 0% at the clay site. These results suggest that switchgrass can contribute significantly to subsoil organic C—but also indicated that this effect varies across sites. Our analysis shows that agricultural strategies that emphasize deep‐rooted grass cultivars can increase soil C relative to conventional crops while expanding energy biomass production on marginal lands. 相似文献
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A recent trend in stable isotopic analysis involves the reconstruction of short-term variations in diet using hair segments. However, bulk hair samples typically contain a growth cycle error, which may conceal or confound the most recently incorporated isotopic information. It is assumed that, at any given time, ～85-90% of scalp hairs are actively growing, while the remaining 10-15% have transitioned into a resting or inactive phase, which lasts up to 4 months before hairs are shed. This study uses growth phase to determine the effects of age, sex, and health status on carbon and nitrogen isotopic ratios of hair analyzed in sequential segments. For this study, we selected archaeological hair samples from 10 individuals from Dakhleh Oasis, Egypt. Isotopic analyses of actively growing hair segments were compared to those for mixed growth phase segments from each individual. These data demonstrate the presence of growth cycle error and show that an understanding of structural-functional relationships is essential for interpreting normal versus pathological changes in hair follicle and fiber production. In situations where diet change and mobility produce variations in an individual's isotopic composition, elimination of positional-temporal error in sequential segment hair analyses can facilitate greater understanding of intraindividual metabolic reactions and changes in hair growth cycles. Phase identification may aid in determining the presence of pathological conditions in individuals, especially in those lacking skeletal indications, and provide a more precise estimation of seasonal dietary patterns, access to changing food resources, and metabolic equilibration to a new locality. 相似文献
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采用碳、氮稳定同位素技术对2012年4-5月长江宜宾江段铜鱼和圆口铜鱼的食物组成进行了分析,并利用多元统计分析方法探讨了铜鱼和圆口铜鱼种间食物关系,包括饵料相似性指数、重叠系数及2种鱼的摄食器官形态差异对食物组成的影响.结果表明:1)铜鱼的δ13C和δ15N变化范围分别为-21.15‰～-20.31‰和9.67‰～ 10.21‰,为偏动物性的杂食性鱼类;圆口铜鱼的δ13C和δ15N分别为-23.30‰～-21.18‰和7.40‰～ 9.21‰,相对铜鱼为偏植物性的杂食性鱼类,铜鱼和圆口铜鱼均与传统肠含物分析的结果存在一定的差异;2)两种鱼的食物相似性指数和食物重叠系数分别为78.7％和55.6％;3)主成分分析(PCA)表明,铜鱼和圆口铜鱼摄食器官形态特征存在一定的差异.长江宜宾江段铜鱼和圆口铜鱼种间竞争不激烈,作为向家坝蓄水前最后一次对长江宜宾江段铜鱼和圆口铜鱼食性及种间食物关系的调查,研究结果可为分析向家坝蓄水对宜宾江段鱼类营养结构的影响提供数据参考. 相似文献
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Salt marshes and shallow-water macroalgal beds are known to provide nursery habitat for many species of fish and invertebrates.
The role of these habitats as refuge from predation is well established, but the degree to which indigenous primary production
within the nursery provides food for growth and development of estuarine species remains unresolved. In this study, we tested
the hypothesis that juvenile blue crabs depend on indigenous primary production, directly or indirectly, during their entire
stay within the nursery. To test this hypothesis, we conducted isotopic studies and stomach content analyses of juveniles
from habitats near the mouth of Delaware Bay and from an adjacent lagoonal estuary (ca. 39.5° N, 75.1° W). Primary producers,
marsh detritus, various life-history stages of blue crabs and potential prey species were sampled in the main estuary and
in an adjacent marsh during the summer and early fall of two consecutive years. Newly settled juveniles (<15 mm carapace width)
from the marsh were about 1.8‰ lighter in carbon (−17.2‰) relative to larger juveniles from the marsh (15–30 mm carapace width)
and appeared to have retained a carbon isotopic signature indicative of the phytoplankton-based food web associated with larval
stages. However, the signature of juveniles changed as a function of size. Large juveniles and crabs >60 mm were enriched
in δ13C (−14.7 ± 0.1‰) compared to small crabs, suggesting a gradual shift in diet from a planktonic to a detritus-based food web
with increasing size. As with crabs from Delaware Bay, the δ13C signature of juvenile crabs sampled from macroalgal beds in the lagoonal estuary (Rehoboth Bay) changed as a function of
size. Also, δ13C ratios of crabs varied among the various species of macroalgae. The δ15N composition of primary producers in the marsh and main estuary also was reflected in the δ15N values of crabs and other benthic consumers in the respective habitats. Results of stomach-content analysis in this study
were consistent with isotope data. Observed changes in prey preferences were related to changes in size of juvenile crabs
and also differed among habitats. Gut content analyses of the three size classes of juveniles in macroalgal beds from Rehoboth
Bay indicated that the crabs depend heavily on various amphipod species that occur on the seaweeds. These amphipods graze
directly on the macroalgae and are among the most abundant invertebrates in the macroalgal beds. This implies a direct trophic
relationship between the juvenile crabs and the macroalgae. In summary, our study provides strong evidence that the value
of nursery areas such as salt marshes and macroalgal beds goes beyond that of providing refuge from predation, and that species
using these nurseries (e.g. juvenile blue crabs) are ultimately dependent on primary production originating in benthic plants
indigenous to the nursery. 相似文献
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Brooke E. Crowley Emilienne Rasoazanabary Laurie R. Godfrey 《American journal of physical anthropology》2014,155(1):77-90
We examine the ecology of reddish‐gray mouse lemurs from three habitats at Beza Mahafaly Special Reserve using focal follows and stable carbon and nitrogen isotope data. Focal observations indicate dietary differences among habitats as well as sexes and seasons. Both sexes consume more arthropods during the rainy season but overall, females consume more sugar‐rich exudates and fruit than males, and individuals from riparian forest consume fewer arthropods and more fruit than those in xeric or dry forest. We ask whether these observations are isotopically detectable. Isotope data support differences between seasons and sexes. Nitrogen isotope values are higher during the rainy season when lemurs consume more arthropods, and higher in males than females, particularly during the dry season. However, differences among populations inferred from focal observations are not fully supported. Lemurs from riparian forest have lower isotope values than those in xeric scrub, but isotope data suggest that lemurs from the dry forest eat the least animal matter and that focal observations overestimated dry forest arthropod consumption. Overall, our results suggest that observational and isotopic data are complementary. Isotope data can be obtained from a larger number of individuals and can quantify ingestion of animal matter, but they apparently cannot quantify the relative consumption of different sugar‐rich foods. Combined focal and isotope data provide valuable insight into the dietary constraints of reddish‐grey mouse lemurs, with implications for their vulnerability to future habitat change. Am J Phys Anthropol 155:77–90, 2014. © 2014 Wiley Periodicals, Inc. 相似文献