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991.
Yang  W.  Deng  D. G.  Meng  X. L.  Zhang  S. 《Russian Journal of Ecology》2019,50(4):352-360
Russian Journal of Ecology - Temporal and spatial variations of phytoplankton community in Lake Erhai were investigated from May 2010 to April 2011. A total of 124 species belonging to 8 phyla and...  相似文献   
992.
The study addresses the potential of using concentrated solar power plants (CSPs) as a sustainable alternative of clean energy generation in the Mediterranean region and, in particular, in its North Africa shore. This location presents attractive conditions for the installation of CSPs, in particular high solar irradiation, good manpower concentration, and proximity and availability of water resources for condenser cooling. Energetic, exergetic, and economic analyses were conducted taking into consideration a particular type of CSPs - the parabolic trough concentrated solar power plant, which incorporates the most proven technology and it is already used in Southern Europe (Spain). In addition, the study considered the impact of project financing and incentives on the cost of energy. The combination of higher values for performance and potentially lower levelized cost of electricity (LCE) for the North Africa Mediterranean Rim than the South of Spain region can yield a very favorable return for the invested capital. Tripoli compared to Almeria presented superior performance and potentially lower LCE values ($0.18/kWh versus $0.22/kWh). This is significant, even when it is taken into consideration the fact that the plant in Tripoli, despite a relatively modest capacity factor of 34%, has a large gross power output of 173,886 MWhe. In addition, the implementation at the Tripoli location of a plant similar to the Anadsol plant has a slight advantage (2–3%) in terms of overall efficiency.  相似文献   
993.
Objectives: Nationally, animal–motor vehicle crashes (AVCs) account for 4.4% of all types of motor vehicle crashes (MVCs). AVCs are a safety risk for drivers and animals and many National Park Service (NPS) units (e.g., national park, national monument, or national parkway) have known AVC risk factors, including rural locations and substantial animal densities. We sought to describe conditions and circumstances involving AVCs to guide traffic and wildlife management for prevention of AVCs in select NPS units.

Methods: We conducted an analysis using NPS law enforcement MVC data. An MVC is a collision involving an in-transit motor vehicle that occurred or began on a public roadway. An AVC is characterized as a collision between a motor vehicle and an animal. A non-AVC is a crash between a motor vehicle and any object other than an animal or noncollision event (e.g., rollover crash). The final data for analysis included 54,068 records from 51 NPS units during 1990–2013. Counts and proportions were calculated for categorical variables and medians and ranges were calculated for continuous variables. We used Pearson’s chi-square to compare circumstances of AVCs and non-AVCs. Data were compiled at the park regional level; NPS parks are assigned to 1 of 7 regions based on the park’s location.

Results: AVCs accounted for 10.4% (5,643 of 54,068) of all MVCs from 51 NPS units. The Northeast (2,021 of 5,643; 35.8%) and Intermountain (1,180 of 5,643; 20.9%) regions had the largest percentage of the total AVC burden. November was the peak month for AVCs across all regions (881 of 5,643; 15.6%); however, seasonality varied by park geographic regions. The highest counts of AVCs were reported during fall for the National Capital, Northeast/Southeast, and Northeast regions; winter for the Southeast region; and summer for Intermountain and Pacific West regions.

Conclusions: AVCs represent a public health and wildlife safety concern for NPS units. AVCs in select NPS units were approximately 2-fold higher than the national percentage for AVCs. The peak season for AVCs varied by NPS region. Knowledge of region-specific seasonality patterns for AVCs can help NPS staff develop mitigation strategies for use primarily during peak AVC months. Improving AVC data collection might provide NPS with a more complete understanding of risk factors and seasonal trends for specific NPS units. By collecting information concerning the animal species hit, park managers can better understand the impacts of AVC to wildlife population health.  相似文献   

994.
Island species are difficult to conserve because they face the synergy of climate change, invasive species, deforestation, and increasing human population densities in areas where land mass is shrinking. The Caribbean island of Hispaniola presents particular challenges because of geopolitical complexities that span 2 countries and hinder coordinated management of species across the island. We employed species distribution modeling to evaluate the impacts of climatic change and anthropogenic activities on the distribution of an endemic mammal of conservation concern, the Hispaniolan solenodon (Solenodon paradoxus). We aggregated occurrence points for this poorly known species for the Last Glacial Maximum (LGM) and the present (1975–2016) based on museum collections, online biodiversity databases, and new field surveys. We quantified degree of overlap between periods and scenarios with Schoener's D. Through a conservation paleobiology lens, we found that over time humans played an increasing role in shaping the distribution of S. paradoxus, thus, providing a foundation for developing conservation strategies on appropriate spatiotemporal scales. Human population density was the single most important predictor of S. paradoxus occurrence. Densities >166 people/km2 corresponded to a near-zero probability of occurrence. Models that accounted for climate but not anthropogenic variables falsely identified suitable habitat in Haiti, where on-the-ground surveys confirm habitat is unavailable. Climate-only models also significantly overestimated the potential for habitat connectivity between isolated populations. Our work highlights that alternative fates for S. paradoxus in the Anthropocene exist across the political border between the Dominican Republic and Haiti due to the fundamentally different economic and political realities of each country. Relationships in the fossil record confirm that Hispaniola's sociopolitical boundary is not biologically significant but instead represents one imposed on the island's fauna in the past 500 years by colonial activity. Our approach reveals how a paleontological perspective can contribute to concrete management insights.  相似文献   
995.

Tendencies in the dynamics of harvested northern fur seal (Callorhinus ursinus) population on the Tyulenii Island have been analyzed in detail. The results show that retardation of reproduction (decrease in the numbers of pups) and decline in the survival of young females (up to 3 years of age) by the late 1980s resulted in a reduction of the total number of females and a significant increase in the proportion of older females. This tendency changed during the later observation period (after 1988–1989) due to increase in the survival of young females: the female population has gradually recovered, with the proportion of young females increasing at the expense of old females (aged over 10 years). The age composition of males has also changed: the proportion of young animals has decreased, while that of large mature males (bulls) has increased. Moreover, the number of bulls continues to increase and has already exceeded the level that formerly provided for the well-being of the population. This, a paradoxical situation has arisen: the numbers of females and bulls are increasing, whereas pup production remains at a low level.

  相似文献   
996.
Widespread human action and behavior change is needed to achieve many conservation goals. Doing so at the requisite scale and pace will require the efficient delivery of outreach campaigns. Conservation gains will be greatest when efforts are directed toward places of high conservation value (or need) and tailored to critical actors. Recent strategic conservation planning has relied primarily on spatial assessments of biophysical attributes, largely ignoring the human dimensions. Elsewhere, marketers, political campaigns, and others use microtargeting—predictive analytics of big data—to identify people most likely to respond positively to particular messages or interventions. Conservationists have not yet widely capitalized on these techniques. To investigate the effectiveness of microtargeting to improve conservation, we developed a propensity model to predict restoration behavior among 203,645 private landowners in a 5,200,000 ha study area in the Chesapeake Bay Watershed (U.S.A.). To isolate the additional value microtargeting may offer beyond geospatial prioritization, we analyzed a new high-resolution land-cover data set and cadastral data to identify private owners of riparian areas needing restoration. Subsequently, we developed and evaluated a restoration propensity model based on a database of landowners who had conducted restoration in the past and those who had not (n = 4978). Model validation in a parallel database (n = 4989) showed owners with the highest scorers for propensity to conduct restoration (i.e., top decile) were over twice as likely as average landowners to have conducted restoration (135%). These results demonstrate that microtargeting techniques can dramatically increase the efficiency and efficacy of conservation programs, above and beyond the advances offered by biophysical prioritizations alone, as well as facilitate more robust research of many social–ecological systems.  相似文献   
997.
998.
Objective: The objective of this study was to explore the evolution footprints of simulated driving research in the past 20 years through rigorous and systematic bibliometric analysis, to provide insights regarding when and where the research was performed and by whom and how the mainstream content evolved over the years.

Methods: The analysis began with data retrieval in Web of Science with defined search terms related to simulated driving. BibExcel and CiteSpace were employed to conduct the performance analysis and co-citation network analysis; that is, probe of the performance of institutes, journals, authors, and research hotspots.

Results: A total of 3,766 documents were filtered out and presented an exponential growth from 1997 to 2016. The United States contributed the most publications as well as international collaborations followed by Germany and China. In addition, several universities in The Netherlands and the United States dominated the list of contributing institutes. The leading journals were in transportation and ergonomics. The leading researchers were also recognized among the 8,721 contributing authors, such as J. D. Lee, D. L. Fisher, J. H. Kim, and K. A. Brookhuis. Finally, the co-citation analysis illuminated the evolution of simulated driving research that covered the following topics roughly in chronological order: task-induced stress, drivers with neurological disorders, alertness and sleepiness while driving, trust toward driving assistance systems, driver distraction, the effect of drug use, the validity of simulators, and automated driving.

Conclusions: This article employed bibliometric tools to probe the contributing countries, institutes, journals, authors, and mainstream hotspots of simulated driving research in the past 20 years. A systematic bibliometric analysis of this field will help researchers realize the panorama of global simulated driving and establish future research directions.  相似文献   

999.
This study evaluated the hydrolysis and photolysis kinetics of pyraclostrobin in an aqueous solution using ultra-high-performance liquid chromatography–photodiode array detection and identified the resulting metabolites of pyraclostrobin by hydrolysis and photolysis in paddy water using high-resolution mass spectrometry coupled with liquid chromatography. The effect of solution pH, metal ions and surfactants on the hydrolysis of pyraclostrobin was explored. The hydrolysis half-lives of pyraclostrobin were 23.1–115.5?days and were stable in buffer solution at pH 5.0. The degradation rate of pyraclostrobin in an aqueous solution under sunlight was slower than that under UV photolysis reaction. The half-lives of pyraclostrobin in a buffer solution at pH 5.0, 7.0, 9.0 and in paddy water were less than 12?h under the two light irradiation types. The metabolites of the two processes were identified and compared to further understand the mechanisms underlying hydrolysis and photolysis of pyraclostrobin in natural water. The extracted ions obtained from paddy water were automatically annotated by Compound Discoverer software with manual confirmation of their fragments. Two metabolites were detected and identified in the pyraclostrobin hydrolysis, whereas three metabolites were detected and identified in the photolysis in paddy water.  相似文献   
1000.
A modified quick, easy, cheap, effective, rugged and safe (QuEChERS) method was developed for the determination of thiamethoxam and its metabolite clothianidin in citrus (including the whole citrus, peel and pulp) and soil samples by liquid chromatography-tandem mass spectrometry. The sample was extracted with acetonitrile and purified with octadecylsilane. The detection limits of both compounds were 0.0001–0.0002?mg kg–1, while the limit of quantification of thiamethoxam was 0.002?mg kg–1 and the limit of quantitation of metabolites was 0.001?mg kg–1. The recovery was 70.37%–109.76%, with inter-day relative standard deviations (RSD) (n?=?15) values ≤9.46% for the two compounds in the four matrices. The degradation curve of thiamethoxam in whole citrus and soil was plotted using the first-order kinetic model. The half-life of the whole citrus was 1.9–6.2?days, and the half-life of the soil was 3.9–4.2?days. The terminal residue of thiamethoxam (the sum of thiamethoxam and clothianidin, expressed as thiamethoxam) was found to be concentrated on the peel. The final residual amount of thiamethoxam in the edible portion (pulp) was less than 0.061?mg kg–1. The risk quotient values were all below 1, indicating that thiamethoxam as a citrus insecticide does not pose a health risk to humans at the recommended dosage.  相似文献   
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