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91.
Environmental monitoring is essential for assessing the current state of the environment, measuring impacts of environmental pressures and providing evidence to government. Recent UK government announcements have indicated an increased role for 'Big Society' in monitoring. In this paper, we review available literature concerning the use of citizen science for monitoring, present examples of successful volunteer monitoring work and highlight important issues surrounding the use of volunteers. We argue that in order to ensure that environmental monitoring continues to be effective it is important to learn from examples where volunteers are currently used, acknowledging constraints and identifying potential approaches which will help to maximise both their engagement and data quality. Effective partnerships between environmental monitoring organisations and volunteers may thus aid the UK in developing robust coordinated monitoring systems that will be less vulnerable to funding variances.  相似文献   
92.
ABSTRACT

Public schools are more than educational institutions; they are essential to creating liveable neighbourhoods. Despite their importance, public schools are being permanently closed across North America, and particularly in the Canadian province of Ontario. In 2015, one of Ontario's public school boards made the decision to permanently close the province's oldest public high school, located in the urban core of the historic midsized city of Kingston. While the school is not scheduled to close until late 2019, the established fate of this prominent public asset has important consequences for the liveability of Kingston's urban core. Accordingly, the objective of this study was to document residents’ perceived impacts of the decision to close to Kingston Collegiate Vocational Institute (KCVI) on liveability in the school's catchment area. We observed widespread dissatisfaction with the decision to close KCVI (85%), with large proportions of respondents (above 40%) anticipating KCVI's closure to negatively impact neighbourhood liveability in various ways in the future. Approximately one-quarter of respondents indicated that they have considered moving as a result of the decision, and among these, concerns about negative impacts to household-level well-being were particularly acute. Given the socio-demographic profile of respondents who have considered moving, these findings suggest that the closure of KCVI could have a destabilising effect on the neighbourhoods within the KCVI catchment area by driving families out of the city's urban core. Our findings suggest that policies to address concerns of under-enrolment are short-sighted and undermine efforts of other sectors to promote liveable communities.  相似文献   
93.
随着我国红色旅游业的快速发展,以翻译为主要途径的外宣工作的重要性日益彰显,如何评价外宣文本的可读性逐渐成为学界关注的热点问题。文中以井冈山景区的英译文本为例,通过问卷调查和访谈的方式收集了十五位目标语读者关于外宣文本的反馈意见。结果显示:译文的可读性受文本质量、文本长度和读者背景等诸多因素的影响。由于译者对英译文本的目标语读者和文本功能认识不足,译文在词汇、语句和语篇等层面均存在不同程度的问题。  相似文献   
94.
An interdisciplinary team introduced Integrated Mite Control (IMC) to the Queensland apple industry in Australia from 1989 to 1992. Project funding supported the employment of a consultant to monitor mite levels and provide management advice to growers who paid for the service. Interviews at the beginning and end of the project showed widespread adoption of IMC over this period. Overall use of chemicals was not reduced, but the use pattern changed towards wider use of chemicals that are less toxic to predatory mites. The future of IMC in the Queensland apple industry is in doubt because the seasonal nature of apple production does not allow the paid consultancy service to be self-sustaining. Indications are that the integrated approach to pest management may not be generally accepted as a strategic management process while the availability of effective chemicals allows the continuation of a spray routine for mite control. The lack of availability of effective and proven methods of pest control was seen by growers as the major constraint to adoption of IMC.  相似文献   
95.
ABSTRACT: Under the terms of the Thames River Valley Flood Control Compact, Connecticut has been paying Massachusetts 40 percent of the annual property tax losses suffered by seven Massachusetts towns where four flood control structures were located. The permissable alternative of a single lump sum payment was investigated in the study summarized here. The lump sum payment should be the proportion of total benefits (flood control and recreation) from the four structures which Connecticut receives, multiplied by the present value of projected tax losses in the seven tom Flood control benefits and their distribution between the two states were fixed in the Compact, but a survey was necessary to determine recreational benefits and their distribution. Regression analysis of 1957 to 1978 tax loss data provided equations used to project future tax losses. Resent values of projected tax low were calculated using discount rates ranging from 6 to 12 percent. A plausible range of lump sum reinbursements as of 1979 was identified.  相似文献   
96.
The U.S. Department of Defense approved activities conducted at the Utah Test and Training Range (UTTR) include both operational readiness test firing of intercontinental ballistic missile motors as well as the destruction of obsolete or otherwise unusable intercontinental ballistic missile motors through open burn/open detonation (OB/ OD). Within the Utah Division of Air Quality, these activities have been identified as having the potential to generate unacceptable noise levels, as well as significant amounts of hazardous air pollutants. Hill Air Force Base, UT, has completed a series of field tests at the UTTR in which sound-monitoring surveillance of OB/OD activities was conducted to validate the Sound Intensity Prediction System (SIPS) model. Using results generated by the SIPS model to support the decision to detonate, the UTTR successfully disposed of missile motors having an aggregate net explosive weight (NEW) of 56,500 lbs without generating adverse noise levels within populated areas. These results suggest that, under appropriate conditions, missile motors of even larger NEW may be detonated without exceeding regulatory noise limits. In conjunction with collecting noise monitoring data, air quality data was collected to support the development of air emission factors for both static missile motor firings and OB/OD activities. Through the installation of 15 ground-based air samplers, the generation of combustion fixed gases, hazardous air pollutants, and chlorides were monitored during the 56,500-lb NEW detonation event. Comparison of field measurements to predictions generated from the U.S. Navy's energetic combustion pollutant formation model, POLU4WN, indicated that, as the detonation fireball expanded from ground zero, organic compounds as well as carbon monoxide continued to oxidize as the hot gases reacted with ambient air. Hazardous air pollutant analysis of air samplers confirmed the presence of chloromethane, benzene, toluene, 1,2-propadiene, and 2-methyl-l-propene, whereas the absence of hydrogen chloride gas suggested that free chlorine is not generated during the combustion process.  相似文献   
97.
Commercial exhaustion of soft-shell clam,Mya arenaria, had become the fate of many potentially productive clamming areas along the coasts of Massachusetts, New Hampshire, and southern Maine. Investigations of a particularly severe case of soft-shell clam stock depletion in Hampton-Seabrook estuary, New Hampshire, indicated that by 1976 human diggers had removed approximately 87% of the adult clam resource that had existed in 1971. Meanwhile, circumstantial evidence strongly implicated the green crab,Carcinus maenas, as responsible for successive stock recruitment failures, these crabs having consumed most of the young seed clams before they could grow to harvestable size. In 1976, this apparent population imbalance may have been at least partly redressed by a prodigious spatfall, resulting in a massive and widespread reseeding of many flats along the northern New England coast. Spat, or seed clam, densities of up to 1,700 individuals per square foot, over areas of several acres, have been observed. Those clamming areas where aggressive predator control programs had been instituted exhibited the most favorable response in terms of seed clam survival and growth. Evidence also indicated that crowding in thickly seeded portions of the clam flats inhibited shell growth.  相似文献   
98.
Socioeconomic, demographic, and attitudinal factors likely to influence individual initiative to use control measures against gypsy moth infestation in New Hampshire are examined. Data were acquired through a mail survey from 629 individuals in three targeted towns: Bow, Conway, and Exeter. Using logit regression analysis, numerous variables are shown to be statistically significant in influencing an individual's willingness to use control measures. The influencing factors include: the individual knowing the difference between the gypsy moth caterpillar and the eastern tent caterpillar; the individual being a homeowner rather than a renter; the number of acres of land accompanying the individual's dwelling; the number of trees on the individual's property; the individual's gender; and the individual's level of income. Aesthetic damage and the nuisance caused by gypsy moth infestation were the primary reasons for individuals to use control measures. The results from this study indicate that the motivation behind an individual's initiative to use control measures is influenced by diverse and varying factors. The models, methodology, and results as applied and presented here are exploratory in nature, yet could prove informative for researchers seeking a greater understanding of the interaction between humans and insect pests.  相似文献   
99.
A series of 90 experiments were conducted in the UC Riverside/CE-CERT environmental chamber to evaluate the impact of water vapor and dissolved salts on secondary organic aerosol formation for cyclohexene ozonolysis. Water vapor (low – 30 ± 2% RH, medium – 46 ± 2% RH, high – 63 ± 2% RH) was found to directly participate in the atmospheric chemistry altering the composition of the condensing species, thus increasing total organic aerosol formation by ~22% as compared to the system under dry (<0.1% RH) conditions. Hygroscopicity measurements also indicate that the organic aerosol composition is altered in the presence of gaseous water. These results are consistent with water vapor reacting with the crigee intermediate in the gas phase resulting in increased aldehyde formation. The addition of dissolved salts ((NH4)2SO4, NH4HSO4, CaCl2, NaCl) had minimal effect; only the (NH4)2SO4 and NaCl were found to significantly impact the system with ~10% increase in total organic aerosol formation. These results indicate that the organics may be partitioning to an outer organic shell as opposed to into the aqueous salt. Hygroscopicity measurements indicate that the addition of salts does not alter the aerosol composition for the dry or water vapor system.  相似文献   
100.
Relative growth rate (RGR) is currently the most commonly used method for measuring and comparing species' intrinsic growth potential. Comparative studies have, for example, revealed that small-seeded species have higher RGR, leading to the common belief that small-seeded species possess physiological adaptations for rapid growth that would allow them to outgrow large-seeded species, given sufficient time. We show that, because RGR declines as individual plants grow, it is heavily biased by initial size and does not measure the size-corrected growth potential that determines the outcome of competition in the long-term. We develop a daily growth model that includes a simple mechanistic representation of aboveground and belowground growth and its dependency on plant size and environmental factors. Intrinsic growth potential is encapsulated by the size-independent growth coefficient, G. We parameterized the model using repeated-harvest data from 1724 plants of nine species growing in contrasting nutrient and temperature regimes. Using information-theoretic criteria, we found evidence for interspecific differences in only three of nine model parameters: G, aboveground allocation, and frost damage. With other parameters shared between species, the model accurately reproduced above- and belowground biomass trajectories for all nine species in each set of environmental conditions. In contrast to conventional wisdom, the relationship between G and seed size was positive, despite a strong negative correlation between seed size and average RGR, meaning that large-seeded rather than small-seeded species have higher size-corrected growth potential. Further, we found a significant positive correlation between G and frost damage that, according to simulations, causes rank reversals in final biomass under daily temperature changes of +/- 5 degrees C. We recommend the wider use of this new kind of plant growth analysis as a better way of understanding underlying differences in species' physiology; but we recognize that RGR is still a useful metric if considering the potential rate of population increase in empty habitats.  相似文献   
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