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1.
A few species of mammals produce group-specific vocalisations that are passed on by learning, but the function of learned vocal variation remains poorly understood. Resident killer whales live in stable matrilineal groups with repertoires of seven to 17 stereotyped call types. Some types are shared among matrilines, but their structure typically shows matriline-specific differences. Our objective was to analyse calls of nine killer whale matrilines in British Columbia to test whether call similarity primarily reflects social or genetic relationships. Recordings were made in 1985–1995 in the presence of focal matrilines that were either alone or with groups with non-overlapping repertoires. We used neural network discrimination performance to measure the similarity of call types produced by different matrilines and determined matriline association rates from 757 encounters with one or more focal matrilines. Relatedness was measured by comparing variation at 11 microsatellite loci for the oldest female in each group. Call similarity was positively correlated with association rates for two of the three call types analysed. Similarity of the N4 call type was also correlated with matriarch relatedness. No relationship between relatedness and association frequency was detected. These results show that call structure reflects relatedness and social affiliation, but not because related groups spend more time together. Instead, call structure appears to play a role in kin recognition and shapes the association behaviour of killer whale groups. Our results therefore support the hypothesis that increasing social complexity plays a role in the evolution of learned vocalisations in some mammalian species.  相似文献   
2.
The consequences of erosion and subsequent sedimentation of lakes and streams are many and widespread. The natural process of erosion can be accelerated by land cover changes with an increase in areas of impervious surfaces. Sediment is continually being transported along all streams in nature and can come from anywhere in the watershed. Lakes slow the rate of velocity of the water and allow the entrained sediment to settle and accumulate. When sediment impacts water impoundments, legal actions may result. Even with evidence of specific sediment release, the forensic analysis may not be an open-and-shut case. The author presents a method to investigate the validity of a legal claim of a sediment-impacted lake at the outfall of a mixed rural/urban watershed. By combining land use change, soils, elevation and precipitation data, a maximum possible annual sediment loss was approximately 154 tonne per hectare (15.4 kg/m2). Lacking evidence of specific historic events of erosion and subsequent sedimentation, this method provides an equitable means of determining compensatory damages. Using aerial and satellite imagery provided historical evidence of land cover change and examples of significant erosion in the watershed and not named in the lawsuit. The focus of the litigation started with the property adjoining the effected lake. The analysis provides a method to investigate erosion and subsequent sedimentation claims at a watershed-scale.  相似文献   
3.
Ten ways remote sensing can contribute to conservation   总被引:1,自引:0,他引:1       下载免费PDF全文
In an effort to increase conservation effectiveness through the use of Earth observation technologies, a group of remote sensing scientists affiliated with government and academic institutions and conservation organizations identified 10 questions in conservation for which the potential to be answered would be greatly increased by use of remotely sensed data and analyses of those data. Our goals were to increase conservation practitioners’ use of remote sensing to support their work, increase collaboration between the conservation science and remote sensing communities, identify and develop new and innovative uses of remote sensing for advancing conservation science, provide guidance to space agencies on how future satellite missions can support conservation science, and generate support from the public and private sector in the use of remote sensing data to address the 10 conservation questions. We identified a broad initial list of questions on the basis of an email chain‐referral survey. We then used a workshop‐based iterative and collaborative approach to whittle the list down to these final questions (which represent 10 major themes in conservation): How can global Earth observation data be used to model species distributions and abundances? How can remote sensing improve the understanding of animal movements? How can remotely sensed ecosystem variables be used to understand, monitor, and predict ecosystem response and resilience to multiple stressors? How can remote sensing be used to monitor the effects of climate on ecosystems? How can near real‐time ecosystem monitoring catalyze threat reduction, governance and regulation compliance, and resource management decisions? How can remote sensing inform configuration of protected area networks at spatial extents relevant to populations of target species and ecosystem services? How can remote sensing‐derived products be used to value and monitor changes in ecosystem services? How can remote sensing be used to monitor and evaluate the effectiveness of conservation efforts? How does the expansion and intensification of agriculture and aquaculture alter ecosystems and the services they provide? How can remote sensing be used to determine the degree to which ecosystems are being disturbed or degraded and the effects of these changes on species and ecosystem functions?  相似文献   
4.
Having volunteers collect data can be a cost-effective strategy to complement or replace those collected by scientists. The quality of these data is essential where field-collected data are used to monitor progress against predetermined standards because they provide decision makers with confidence that choices they make will not cause more harm than good. The integrity of volunteer-collected data is often doubted. In this study, we made estimates of seven vegetation attributes and a composite measure of six of those seven, to simulate benchmark values. These attributes are routinely recorded as part of rehabilitation projects in Australia and elsewhere in the world. The degree of agreement in data collected by volunteers was compared with those recorded by professional scientists. Combined results showed that scientists collected data that was in closer agreement with benchmarks than those of volunteers, but when data collected by individuals were analyzed, some volunteers collected data that were in similar or closer agreement, than scientists. Both groups’ estimates were in closer agreement for particular attributes than others, suggesting that some attributes are more difficult to estimate than others, or that some are more subjective than others. There are a number of ways in which higher degrees of agreement could be achieved and introducing these will no doubt result in better, more effective programs, to monitor rehabilitation activities. Alternatively, less subjective measures should be sought when developing monitoring protocols. Quality assurance should be part of developing monitoring methods and explicitly budgeted for in project planning to prevent misleading declarations of rehabilitation success.  相似文献   
5.
A prototype Free-Air Controlled Enrichment (FACE) system was developed at Brookhaven National "Laboratory (BNL) for the experimental control of gas concentrations in an open field, without any form of enclosure. This FACE system consists of a toroidal plenum chamber, 15 m in diameter, with a series of 32 vertical vent pipes from which the release of a test gas can be controlled. Data on gas concentration at the center of the array and wind velocity are fed to a microprocessor where a proportional, integrative, differential (PID) algorithm is used to regulate a mass-flow controller. Data on wind direction are used to control the opening and closing of the vertical vent pipes to maintain an upwind release. In 72 hours of continuous operation during which wind velocity varied between 0.3 to 8 m sec-1, the FACE prototype maintained 1 -min averaged concentrations within twenty percent of the 40 ppb set point 94 percent of the time.  相似文献   
6.
Published results of four field experiments testing effects of acidic precipitation in field-grown soybeans have led to contradictory conclusions. This paper examines the experimental procedures and protocols of the four experiments which could have contributed to differences in both the reported crop yields and the interpretations or conclusions drawn from the experiments.

The most important difference among the experiments is in their statistical designs. Two of the field layouts used only one plot per treatment, providing replication only for plants, rows or sectors within plots, but not among plots. By using real data from a highly replicated experiment it is shown that with such deficient statistical designs treatment effects cannot be separated from other microenvironmental variables peculiar to a specific plot location.

The other two experiments were highly replicated. They were designed to detect differences of approximately 10% among treatment means. Type 1 error, a, was predetermined, and replication was sufficient to keep type 2 error low. This design was made possible because a preliminary experiment was available to estimate the expected components of variance. Despite differences in the procedures and protocols among the four experiments, it is primarily the quality of the experimental design which has determined their validity and relative utility for crop loss assessment.  相似文献   
7.
Industrial activity is one of the main sources of ambient pollution in developed countries. However, research analyzing its effect on birth outcomes is inconclusive. We analyzed the association between proximity of mother’s municipality of residence to industries from 24 different activity groups and risk of very (VPTB) and moderate (MPTB) preterm birth, very (VLBW) and moderate (MLBW) low birth weight, and small for gestational age (SGA) in Spain, 2004–2008. An ecological study was defined, and a “near vs. far” analysis (3.5 km threshold) was carried out using Hierarchical Bayesian models implemented via Integrated Nested Laplace Approximation. VPTB risk was higher for mothers living near pharmaceutical companies. Proximity to galvanization and hazardous waste management industries increased the risk of MPTB. Risk of VLBW was higher for mothers residing near pharmaceutical and non-hazardous or animal waste management industries. For MLBW many associations were found, being notable the proximity to mining, biocides and animal waste management plants. The strongest association for SGA was found with proximity to management animal waste plants. These results highlight the importance of further research on the relationship between proximity to industrial sites and the occurrence of adverse birth outcomes especially for the case of pharmaceutical and animal waste management activities.  相似文献   
8.
The Underwater Radiation Spectral Identification System (URSIS) is a portable spectrometer used for the in situ detection of radioactivity in the marine environment. This paper reports on the first time application of this technology to assess, in a preliminary manner, the potential radiation threat to the public and environment at an aquatic disposal site – the Massachusetts Bay Industrial Waste Site (IWS). Utilizing the meneuvering capabilities of ROV and manned submersible vehicles, the URSIS was successfully positioned close (5–10 cm) to waste containers for a period sufficient to detect, in real time, the presence of radioactive materials. Spectral data from 45 individual targets indicated that the radionuclides present in sediments which draped or partially buried waste containers were consistent with natural background concentrations. No man-made radionuclides were detected at any of the target or background measurement locations. These data support the conclusion that low-level radiation does not pose an imminent and widespread human health or ecological threat in Massachusetts Bay.  相似文献   
9.
ABSTRACT: A methodology for ground water remediation design has been developed that interfaces ground water simulation models with an enhanced annealing optimizer. The ground water flow and transport simulators provide the ability to consider site‐specific contamination and geohydrologic conditions directly in the assessment of alternative remediation system designs. The optimizer facilitates analysis of tradeoffs between technical, environmental, regulatory, and financial risks for alternative design and operation scenarios. A ground water management model using an optimization method referred to as “enhanced annealing” (simulated annealing enhanced to include “directional search” and “memory” mechanisms) has been developed and successfully applied to an actual restoration problem. The demonstration site is the contaminated unconfined aquifer referred to as N‐Springs located at Han‐ford, Washington. Results of the demonstration show the potential for improving groundwater restoration system performance while reducing overall system cost.  相似文献   
10.
A field pilot test in which hydraulic fracturing was used to emplace granular remediation amendment (a mixture of zero‐valent iron [ZVI] and organic carbon) into fine‐grained sandstone to remediate dissolved trichloroethene (TCE)‐contaminated groundwater was performed at a former intercontinental ballistic missile site in Colorado. Hydraulic fracturing was used to enhance the permeability of the aquifer with concurrent emplacement of amendment that facilitates TCE degradation. Geophysical monitoring and inverse modeling show that the network of amendment‐filled fractures extends throughout the aquifer volume targeted in the pilot test zone. Two years of subsequent groundwater monitoring demonstrate that amendment addition resulted in development of geochemical conditions favorable to both abiotic and biological TCE degradation, that TCE concentrations were substantially reduced (i.e., greater than 90 percent reduction in TCE mass), and that the primary degradation processes are likely abiotic. The pilot‐test data aided in re‐evaluating the conceptual site model and in designing the full‐scale remedy to address a larger portion of the TCE‐contaminated groundwater plume. © 2012 Wiley Periodicals, Inc.  相似文献   
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