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261.
João Porteiro Helena Calado Margarida Pereira Adriano Quintela Tomáz Dentinho 《国际发展与全球生态学杂志》2013,20(2):192-200
The Sete Cidades Lake (437 ha) is located in a volcanic crater of São Miguel Island (Azores). The watershed is 1923 ha, and 25% of it is covered with water. Extreme logging and the use of fertilizers in the cattle grazing areas have caused sedimentation and eutrophication of the main water body (Carlson Trophic State Index TSI = 40–50 mesoeutrophy). To deal with the issue, a linear programming model was created to generate efficient land-use scenarios for different amounts of phosphorus release. The model was calibrated for the present situation and then simulated to obtain 29 scenarios. It allowed us to derive parameters for each scenario. Then a multiobjective program was used to derive an acceptable weight for each indicator. The dominant solutions were discovered and discussed with different stakeholders. 相似文献
262.
The Wadden Sea is an important habitat for harbour seals and grey seals. They regularly haul-out on sandbanks and islands
along the coast. Comparably little is known about the time seals spend at sea and how they use the remainder of the North
Sea. Yet, human activity in offshore waters is increasing and information on seal distribution in the North Sea is crucial
for conservation and management. Aerial line transect surveys were conducted in the German bight from 2002 to 2007 to investigate
the distribution and abundance of marine mammals. Distance sampling methodology was combined with density surface modelling
for a spatially explicit analysis of seal distribution in the German North Sea. Depth and distance to coast were found to
be relevant predictor variables for seal density. Density surface modelling allowed for a depiction of seal distribution in
the study area as well as an abundance estimate. This is the first study to use aerial survey data to develop a density surface
model (DSM) for a spatially explicit distribution estimate of seals at sea.
相似文献
Helena HerrEmail: |
263.
Geospatial analysis of vulnerable beach-foredune systems from decadal time series of lidar data 总被引:1,自引:0,他引:1
Helena Mitasova Eric Hardin Margery F. Overton Mustafa Onur Kurum 《Journal of Coastal Conservation》2010,14(3):161-172
Time series of lidar data, acquired over the past decade along the North American East Coast, provide opportunities to gain
new insights into 3D evolution of barrier islands and their beach and dune systems. GIS-based per grid cell statistics and
map algebra was applied to time series of Digital Surface Models representing two sections of North Carolina barrier islands
to quantify elevation change trends, map dynamic and stable locations, identify new and lost buildings, measure relative volume
evolution in the beach and foredune systems and analyze shoreline dynamics. Results show a relatively small stable core in
both study areas, with beaches and the ocean side of the dunes exhibiting systematic high rates of elevation loss while areas
landward from the dunes increase slightly in elevation. Significant number of new homes have been built at locations with
very small core surface elevation, and homes built within the shoreline dynamics band have already been lost. The raster-based
methodology used in this study can be applied to perform similar analyses in other coastal areas where time series of lidar
data are available. 相似文献
264.
PROBLEM: Suicide is a dominating, although hidden, safety problem on Swedish railroads. The aim of this paper is to describe the epidemiology of fatal train-person collisions as a basis for systems-oriented prevention. METHOD: Data on collision circumstances were collected from narrative reports at the Swedish National Rail Administration. RESULTS: The events were evenly distributed by months and weekdays, however, most suicides occur during the day while unintentional events usually occur at night. Most train-person collisions happened in densely populated areas, and 75% of the suicide victims were waiting on the track before the collision. Significance test between types of injury event (suicide, accident, or unknown intent) showed small or no differences. CONCLUSION: Traditional approaches to accident prevention by systems modification seem largely applicable to combat railroad suicide as well. IMPACT ON INDUSTRY: Our findings show promising preventive potentials. 相似文献
265.
Leticia Burone Silvia Helena de Mello e Sousa Michel Michaelovitch de Mahiques Paulo Valente Aurea Ciotti Cíntia Yamashita 《Marine Biology》2011,158(1):159-179
Foraminiferal data were obtained from 66 samples of box cores on the southeastern Brazilian upper margin (between 23.8°–25.9°S
and 42.8°–46.13°W) to evaluate the benthic foraminiferal fauna distribution and its relation to some selected abiotic parameters.
We focused on areas with different primary production regimes on the southern Brazilian margin, which is generally considered
as an oligotrophic region. The total density (D), richness (R), mean diversity ([`(H¢ )] \overline{{H^{\prime } }} ), average living depth (ALD
X
) and percentages of specimens of different microhabitats (epifauna, shallow infauna, intermediate infauna and deep infauna)
were analyzed. The dominant species identified were Uvigerina spp., Globocassidulina subglobosa, Bulimina marginata, Adercotryma wrighti, Islandiella norcrossi, Rhizammina spp. and Brizalina sp.. We also established a set of mathematical functions for analyzing the vertical foraminiferal distribution patterns, providing
a quantitative tool that allows correlating the microfaunal density distributions with abiotic factors. In general, the cores
that fit with pure exponential decaying functions were related to the oligotrophic conditions prevalent on the Brazilian margin
and to the flow of the Brazilian Current (BC). Different foraminiferal responses were identified in cores located in higher
productivity zones, such as the northern and the southern region of the study area, where high percentages of infauna were
encountered in these cores, and the functions used to fit these profiles differ appreciably from a pure exponential function,
as a response of the significant living fauna in deeper layers of the sediment. One of the main factors supporting the different
foraminiferal assemblage responses may be related to the differences in primary productivity of the water column and, consequently,
in the estimated carbon flux to the sea floor. Nevertheless, also bottom water velocities, substrate type and water depth
need to be considered. 相似文献
266.
Simultaneous ground-based measurements of ozone and carbon monoxide were performed at Oki, Japan, from January 2001 to September 2002 in order to investigate the O(3) and CO characteristics and their distributions. The observations revealed that O(3) and CO concentrations were maximum in springtime and minimum in the summer. The monthly averaged concentrations of O(3) and CO were 60 and 234 ppb in spring and 23 and 106 ppb in summer, respectively. Based on direction, 5-day isentropic backward trajectory analysis was carried out to determine the transport path of air masses, preceding their arrival at Oki. Comparison between classified results from present work and results from the year 1994-1996 was carried out. The O(3) and CO concentration results of classified air masses in our analysis show similar concentration trends to previous findings; highest in the WNW/W, lowest in N/NE and medium levels in NW. Moreover, O(3) levels are higher and CO levels are lower in the present study in all categories. 相似文献
267.
This Incubator introduces scholars to death awareness research. We explicate how mortality salience can be studied in conjunction with workplace behavior. Using the Terror Management Theory (TMT) framework, we explore morality salience in combination with several workplace phenomena, including aggression, discrimination, and punishment; and, several ideas for future research are suggested. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
268.
269.
Klementová Šárka Poncarová Martina Langhansová Helena Lieskovská Jaroslava Kahoun David Fojtíková Pavla 《Environmental science and pollution research international》2022,29(10):13941-13962
Environmental Science and Pollution Research - Photochemical degradation of fluoroquinolones ciprofloxacin, enrofloxacin and norfloxacin in aqueous solution under light conditions relevant to... 相似文献
270.
A new heterogeneous photocatalyst was prepared by oxidative polymerization of the thiophene with ferric chloride in the ZSM-5 zeolite type. The synthesized polythiophene absorbs radiation in the visible range of the electromagnetic spectrum and by illumination with visible light generates reactive oxygen species (ROS) in water medium. During illumination reactive hydroxyl radical was detected by the spin trapping EPR method. Efficiency of the photocatalyst was tested on the killing of Gram-positive bacteria Staphylococcus aureus and Gram negative bacteria Escherichia coli. 相似文献