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51.
Silk JB Beehner JC Bergman TJ Crockford C Engh AL Moscovice LR Wittig RM Seyfarth RM Cheney DL 《Behavioral ecology and sociobiology》2010,64(11):1733-1747
Analyses of the pattern of associations, social interactions, coalitions, and aggression among chacma baboons (Papio hamadryas ursinus) in the Okavango Delta of Botswana over a 16-year period indicate that adult females form close, equitable, supportive, and
enduring social relationships. They show strong and stable preferences for close kin, particularly their own mothers and daughters.
Females also form strong attachments to unrelated females who are close to their own age and who are likely to be paternal
half-sisters. Although absolute rates of aggression among kin are as high as rates of aggression among nonkin, females are
more tolerant of close relatives than they are of others with whom they have comparable amounts of contact. These findings
complement previous work which indicates that the strength of social bonds enhances the fitness of females in this population
and support findings about the structure and function of social bonds in other primate groups. 相似文献
52.
2007年11月21日,大自然保护协会(TNC)气候变化专家Barry Baker博士应邀来到北京环境记者沙龙发表演讲。Barry Baker博士长期以来一直关注气候变化对大自然生态系统以及人类生存所带来的挑战。作为一个科学家,他和自己的工作小组一起深入云南横断山区、青海长江源区以及西藏、新疆等自然保护区进行考察、测量,以严谨、精湛的科学精神, 相似文献
53.
Alvarez-Pedrerol M Ribas-Fitó N Torrent M Carrizo D Garcia-Esteban R Grimalt JO Sunyer J 《Environment international》2008,34(6):737-740
OBJECTIVE: Thyroid hormones play an important role in human brain development, and some organochlorine compounds (OCs) act as thyroid disruptors. The objective of the present study was to evaluate the association between prenatal exposure to organochlorine compounds and thyroid function in newborns from a general population birth cohort in Menorca, with an a-priori specific focus on beta-HCH. METHODS: Levels of polychlorinated biphenyls (PCB congeners 28, 52, 101, 118, 138, 153 and 180), hexachlorobenzene (HCB), beta-hexachlorocyclohexane (beta-HCH), dichlorodiphenyl dichloroethylene (p'p'-DDE) and dichlorodiphenyl trichloroethane (p'p-DDT) in cord serum, and thyrotropin (TSH) concentration in plasma three days after birth were measured in 387 newborns from Menorca. The TSH concentration was categorized (high or low), except for 27 children whose TSH levels were quantified. RESULTS: Levels of beta-HCH and PCB-153 were positively related to TSH concentrations (gestational age-adjusted coefficient (p-value): 0.26 (p = 0.006) and 0.31 (p = 0.050), respectively). CONCLUSIONS: beta-HCH is potentially a new thyroid disrupting compound, deserving special interest in future studies given its high body burden in humans. 相似文献
54.
Anthropogenic impairment of water bodies represents a global environmental concern, yet few attempts have successfully linked
fish performance to thermal habitat suitability and fewer have distinguished co-varying water quality constraints. We interfaced
fish bioenergetics, field measurements, and Thermal Remote Imaging to generate a spatially-explicit, high-resolution surface
of fish growth potential, and next employed a structured hypothesis to detect relationships among measures of fish performance
and co-varying water quality constraints. Our thermal surface of fish performance captured the amount and spatial-temporal
arrangement of thermally-suitable habitat for three focal species in an extremely heterogeneous reservoir, but interpretation
of this pattern was initially confounded by seasonal covariation of water residence time and water quality. Subsequent path
analysis revealed that in terms of seasonal patterns in growth potential, catfish and walleye responded to temperature, positively
and negatively, respectively; crappie and walleye responded to eutrophy (negatively). At the high eutrophy levels observed
in this system, some desired fishes appear to suffer from excessive cultural eutrophication within the context of elevated
temperatures whereas others appear to be largely unaffected or even enhanced. Our overall findings do not lead to the conclusion
that this system is degraded by pollution; however, they do highlight the need to use a sensitive focal species in the process
of determining allowable nutrient loading and as integrators of habitat suitability across multiple spatial and temporal scales.
We provide an integrated approach useful for quantifying fish growth potential and identifying water quality constraints on
fish performance at spatial scales appropriate for whole-system management. 相似文献
55.
Claudia Hollatz Leonardo Flach C. Scott Baker Fabrício R. Santos 《Marine Biology》2011,158(4):927-933
A large macrogeographic differentiation has been observed among Sotalia guianensis populations along the South American coast. However, no genetic structure has been detected so far in closely distributed
populations of this species, even though it has been observed in other cetaceans. Here, we examined the fine scale population
structure for the largest populations of S. guianensis inhabiting Sepetiba and Paraty embayments at the south-eastern coast of Rio de Janeiro, Brazil. Analysis of mitochondrial
DNA (mtDNA) control region sequences failed to detect variability among sequences. Conversely, evidence of significant male
population structure was found on the basis of ten nuclear microsatellite loci. Surprisingly, the microsatellite markers were
able to distinguish between individuals from the two embayments located 60 km apart. The results suggest that differences
in habitat type and behavioral specializations are likely to explain the patterns of genetic structure. These findings should
provide baselines for the management of communities exposed to increasing human-driven habitat loss. 相似文献
56.
Knowledge gain and behavioral change in citizen-science programs 总被引:1,自引:0,他引:1
Citizen-science programs are often touted as useful for advancing conservation literacy, scientific knowledge, and increasing scientific-reasoning skills among the public. Guidelines for collaboration among scientists and the public are lacking and the extent to which these citizen-science initiatives change behavior is relatively unstudied. Over two years, we studied 82 participants in a three-day program that included education about non-native invasive plants and collection of data on the occurrence of those plants. Volunteers were given background knowledge about invasive plant ecology and trained on a specific protocol for collecting invasive plant data. They then collected data and later gathered as a group to analyze data and discuss responsible environmental behavior with respect to invasive plants. We tested whether participants without experience in plant identification and with little knowledge of invasive plants increased their knowledge of invasive species ecology, participation increased knowledge of scientific methods, and participation affected behavior. Knowledge of invasive plants increased on average 24%, but participation was insufficient to increase understanding of how scientific research is conducted. Participants reported increased ability to recognize invasive plants and increased awareness of effects of invasive plants on the environment, but this translated into little change in behavior regarding invasive plants. Potential conflicts between scientific goals, educational goals, and the motivation of participants must be considered during program design. 相似文献
57.
We report a fetus with hydrops, congenital heart disease and bilateral radioulnar synostosis caused by a novel pathogenic MECOM variant. The female fetus was referred for post-mortem examination after fetal hydrops and intrauterine death was diagnosed at 20 weeks gestation. Post-mortem examination confirmed fetal hydrops, pallor, truncus arteriosus and bilateral radioulnar synostosis. Trio whole genome sequencing analysis detected a novel de novo heterozygous pathogenic loss-of-function variant in MECOM (NM_004991), associated with a diagnosis of Radioulnar Synostosis with Amegakaryocytic Thrombocytopenia 2 (RUSAT-2). RUSAT-2 is a variable condition associated postnatally with bone marrow failure, radioulnar synostosis and congenital anomalies. RUSAT-2 is not currently associated with a prenatal phenotype or fetal demise, and was not present on diagnostic NHS prenatal gene panels at time of diagnosis. This case highlights the diagnostic value of detailed phenotyping with post-mortem examination, and of using a broad sequencing approach. 相似文献
58.
Jabiol Jérémy Chauvet Eric Guérold François Bouquerel Jonathan Usseglio-Polatera Philippe Artigas Joan Margoum Christelle Le Dréau Matthieu Moreira Aurélie Mazzella Nicolas Gouy Véronique 《Environmental science and pollution research international》2022,29(20):29296-29313
Environmental Science and Pollution Research - Freshwater contamination by pesticides in agricultural landscapes is of increasing concern worldwide, with strong pesticide impacts on biodiversity,... 相似文献
59.
Given recent focus on large rivers as conduits for excess nutrients to coastal zones, their role in processing and retaining nutrients has been overlooked and understudied. Empirical measurements of nutrient uptake in large rivers are lacking, despite a substantial body of knowledge on nutrient transport and removal in smaller streams. Researchers interested in nutrient transport by rivers (discharge >10000 L/s) are left to extrapolate riverine nutrient demand using a modeling framework or a mass balance approach. To begin to fill this knowledge gap, we present data using a pulse method to measure inorganic nitrogen. (N) transport and removal in the Upper Snake River, Wyoming, USA (seventh order, discharge 12000 L/s). We found that the Upper Snake had surprisingly high biotic demand relative to smaller streams in the same river network for both ammonium (NH4+) and nitrate (NO3-). Placed in the context of a meta-analysis of previously published nutrient uptake studies, these data suggest that large rivers may have similar biotic demand for N as smaller tributaries. We also found that demand for different forms of inorganic N (NH4+ vs. NO3-) scaled differently with stream size. Data from rivers like the Upper Snake and larger are essential for effective water quality management at the scale of river networks. Empirical measurements of solute dynamics in large rivers are needed to understand the role of whole river networks (as opposed to stream reaches) in patterns of nutrient export at regional and continental scales. 相似文献
60.
Matthew E. Baker Michael J. Wiley Paul W Seelbach 《Journal of the American Water Resources Association》2001,37(6):1615-1628
ABSTRACT: Riparian buffers have potential for reducing excess nutrient levels in surface water. Spatial variation in riparian buffer effectiveness is well recognized, yet researchers and managers still lack effective general tools for understanding the relevance of different hydrologic settings. We present several terrain‐based GIS models to predict spatial patterns of shallow, subsurface hydrologic flux and riparian hydrology. We then link predictions of riparian hydrology to patterns of nutrient export in order to demonstrate potential for augmenting the predictive power of land use/land cover (LU/LC) maps. Using predicted hydrology in addition to LUILC, we observed increases in the explained variation of nutrient exports from 290 sites across Lower Michigan. The results suggest that our hydrologic predictions relate more strongly to patterns of nutrient export than the presence or absence of wetland vegetation, and that in fact the influence of vegetative structure largely depends on its hydrologic context. Such GIS models are useful and complimentary tools for exploring the role of hydrologic routing in riparian ecosystem function and stream water quality. Modeling efforts that take a similar GIS approach to material transport might be used to further explore the causal implications of riparian buffers in heterogeneous watersheds. 相似文献