Temporal and spatial stratification for the estimation of nocturnal long-term noise levels

Effects of climatic changes in transitional ecosystems are often not linear, with some areas likely experiencing faster or more intense responses, which something important to consider in the perspective of climate forecasting. In this study of the Venice lagoon, time series of the past decade were used, and primary productivity was estimated from hourly oxygen data using a published model. Temporal and spatial patterns of water temperature, salinity and productivity time series were identified by applying clustering analysis. Phytoplankton and nutrient data from long-term surveys were correlated to primary productivity model outputs. pmax, the maximum oxygen production rate in a given day, was found to positively correlate with plankton variables measured in surveys. Clustering analysis showed the occurrence of summer heatwaves in 2008, 2013, 2015 and 2018 and three warm prolonged summers (2012, 2017, 2019) coincided with lower summer pmax values. Spatial effects in terms of temperature were found with segregation between confined and open areas, although the patterns varied from year to year. Production and respiration differences showed that the lagoon, despite seasonality, was overall heterotrophic, with internal water bodies having greater values of heterotrophy. Warm, dry years with high salinity had lower degrees of summer autotrophy.

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Snow Avalanches and Acoustic Emissions

Annals of Glaciology ◽

10.3189/s0260305500005590 ◽

1983 ◽

Vol 4 ◽

pp. 271-276 ◽

Cited By ~ 5

Author(s):

R. A. Sommerfeld ◽

H. Gubler

Keyword(s):

Acoustic Emissions ◽

Limited Range ◽

Slope Instability ◽

Type I ◽

Type Ii ◽

Noise Levels ◽

Active Layers ◽

Differential Movement ◽

Emission Activity

Analyses of several years of data show that acoustic emission activity is greater from unstable snowpacks than from stable snowpacks. Two types of signals have been identified: type I spikes and type II long-term elevation of the noise level. It is thought that the type I signals originate from macroscopic cracks. The type II signals may originate from differential movement on shearing surfaces, but this is less certain. Increased noise levels of both types correlate well with slope instability, when the slope stability is known. In some climates the limited range of signal detection might be a significant problem. A foam-mounted geophone set into the snow near active layers appears to be the best sensor available at present.

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Using spoor and prey counts to determine temporal and spatial variation in lion (Panthera leo) density

Canadian Journal of Zoology ◽

10.1139/cjz-2013-0176 ◽

2014 ◽

Vol 92 (2) ◽

pp. 97-104 ◽

Cited By ~ 10

Author(s):

D. Bauer ◽

M. Schiess-Meier ◽

D.R. Mills ◽

M. Gusset

Keyword(s):

Spatial Variation ◽

Disease Outbreaks ◽

Panthera Leo ◽

African Countries ◽

Temporal And Spatial Variation ◽

Term Survival ◽

Population Crash ◽

Grazing Area ◽

Temporal And Spatial

In many African countries, large carnivores such as lions (Panthera leo (L., 1758)) are under serious threat through conflict with people, declining prey abundance, and exposure to disease. Spoor and prey count surveys were used to determine temporal and spatial variation in lion density in Khutse Game Reserve (KGR), Botswana, and the adjacent communal grazing area. Estimated lion density in KGR for the period September 2008 – June 2010 was 41% lower than for the period June 2007 – August 2008 (1.02 vs. 1.72 lions/100 km2). Prior to this population crash in mid-2008, estimated lion density in the communal grazing area (1.21 lions/100 km2) was 30% lower than inside KGR. The relative abundance of the three most abundant, preferred prey species of lions occurring in KGR decreased from 2001 to 2008 by 50%–79%. Based on two prey biomass estimates, the lion population in KGR was below the potential carrying capacity of the habitat after the crash in mid-2008. These results suggest that there could be a human-caused population sink around KGR, which might be strong enough to threaten the long-term survival of lions in the area; particularly if this edge effect is intensified by prey depletion and disease outbreaks, which might have caused the sudden decline in the lion population.

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Precarious city: home-making and eviction in Buenos Aires, Argentina

Cultural Geographies ◽

10.1177/1474474017719068 ◽

2017 ◽

Vol 25 (3) ◽

pp. 411-424 ◽

Cited By ~ 6

Author(s):

Solange Muñoz

Keyword(s):

Everyday Life ◽

Buenos Aires ◽

City Center ◽

Place Making ◽

Domestic Spaces ◽

The Everyday ◽

Temporal And Spatial ◽

The City ◽

Traditional Roles

This article expands on current conceptualizations and applications of precarity by exploring the everyday socio-spatial complexities of migrant squatters living in informal hotels in the center of Buenos Aires, Argentina. Through ethnographic methods, this research investigates squatters’ practices of negotiating access to shared domestic spaces and resources, while experiencing long-term waiting for eviction from their home and potentially from the city center. Employing a cultural geographies approach, this work is concerned with understanding the ways in which precarity is routinely experienced in the micro-spaces of everyday life. Precarity is examined in its temporal and spatial manifestations, with particular emphasis on gendered experiences and home-making practices. Moving through daily spaces and routine situations, I document how precarity is embedded in the mundane tasks of the domestic, and as a result, unevenly impacts women whose traditional roles as mothers and caretakers mean that they are often at the fore of place-making practices and responsibilities.

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Measuring Sound at a Cold-Water Coral Reef to Assess the Impact of COVID-19 on Noise Pollution

Frontiers in Marine Science ◽

10.3389/fmars.2021.674702 ◽

2021 ◽

Vol 8 ◽

Author(s):

Laurence H. De Clippele ◽

Denise Risch

Keyword(s):

Coral Reef ◽

Coral Reefs ◽

Sea Level ◽

Cold Water ◽

Noise Pollution ◽

Ecosystem Functions ◽

Noise Levels ◽

Level Height ◽

Water Coral

This study compares the noise levels at the cold-water coral Tisler reef, before and after the closure of the border between Norway and Sweden, which occurred as a direct result of the COVID-19 pandemic. The Tisler reef is a marine protected area located under a ferry “highway” that connects Norway and Sweden. Cold-water coral reefs are recognised as being important hotspots of both biodiversity and biomass, they function as breeding and nursing grounds for commercially important fish and are essential in providing ecosystem functions. Whilst studies have shown that fishery, ocean warming, and acidification threaten them, the effects of noise pollution on cold-water coral reefs remains unstudied. To study the severity of noise pollution at the Tisler reef, a long-term acoustic recorder was deployed from 29 January 2020 until 26 May 2020. From 15 March COVID-19 lockdown measures stopped passenger vessel traffic between Norway and Sweden. This study found that the overall noise levels were significantly lower after border closure, due to reduced ferry traffic, wind speeds, and sea level height. When comparing the median hourly noise levels of before vs. after border closure, this study measured a significant reduction in the 63–125 Hz 1/3 octave band noise levels of 8.94 ± 0.88 (MAD) dB during the day (07:00:00–19:59:59) and 1.94 ± 0.11 (MAD) dB during the night (20:00:00–06:59:59). Since there was no ferry traffic during the night, the drop in noise levels at night was likely driven by seasonal changes, i.e., the reduction in wind speed and sea level height when transitioning from winter to spring. Taking into account this seasonal effect, it can be deduced that the COVID-19 border closure reduced the noise levels in the 63–125 Hz 1/3 octave bands at the Tisler reef by 7.0 ± 0.99 (MAD) dB during the day. While the contribution of, and changes in biological, weather-related and geophysical sound sources remain to be assessed in more detail, understanding the extent of anthropogenic noise pollution at the Tisler cold-water coral reef is critical to guide effective management to ensure the long-term health and conservation of its ecosystem functions.

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Long-term temporal and spatial trends in eutrophication status of the Baltic Sea

Biological Reviews ◽

10.1111/brv.12221 ◽

2015 ◽

Vol 92 (1) ◽

pp. 135-149 ◽

Cited By ~ 108

Author(s):

Jesper H. Andersen ◽

Jacob Carstensen ◽

Daniel J. Conley ◽

Karsten Dromph ◽

Vivi Fleming-Lehtinen ◽

...

Keyword(s):

Baltic Sea ◽

The Baltic Sea ◽

Spatial Trends ◽

Temporal And Spatial ◽

The Baltic ◽

Temporal And Spatial Trends

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Long-term Temporal and Spatial Morphological Variability of a Nourished Beach Using the EOF Analysis

Journal of Coastal Research ◽

10.2112/si95-083.1 ◽

2020 ◽

Vol 95 (sp1) ◽

pp. 428

Author(s):

Tae-Jin Choi ◽

Jin-Yong Choi ◽

Jun-Yong Park ◽

Young-Jin Yang

Keyword(s):

Morphological Variability ◽

Eof Analysis ◽

Temporal And Spatial

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Introduction

The Occupation of Havana ◽

10.5149/northcarolina/9781469645353.003.0001 ◽

2018 ◽

pp. 1-14

Author(s):

Elena A. Schneider

Keyword(s):

Crucial Role ◽

Slave Trade ◽

African Descent ◽

Event History ◽

Major Event ◽

Black Soldiers ◽

History Of ◽

Temporal And Spatial

The introduction sketches the contours of the British six-week invasion and eleven-month occupation of Havana in 1762–1763, a major event in the history of the Atlantic world. It describes the framework of the book, “an event history” that relies on multiple, overlapping temporal and spatial frames in order to tie together many different strands of history, historical actors, perspectives, and scales. In giving a long-term history of the causes, central dynamics, and enduring consequences of this event, the book focuses on the crucial role of the slave trade and people of African descent. The actions of people of African descent and imperial rivalry over the slave trade shaped both the invasion and occupation of Havana in ways yet to be fully understood. The rest of the book explores the painful irony that black soldiers’ brave service in Havana during the British siege helped lead to new Spanish policies that endorsed and expanded slavery and the slave trade.

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Hydrodynamical Adaptive Mesh Refinement Simulations of Disk Galaxies

Proceedings of the International Astronomical Union ◽

10.1017/s1743921308027956 ◽

2008 ◽

Vol 4 (S254) ◽

pp. 445-452

Author(s):

Brad K. Gibson ◽

Stéphanie Courty ◽

Patricia Sánchez-Blázquez ◽

Romain Teyssier ◽

Elisa L. House ◽

...

Keyword(s):

Galaxy Formation ◽

Adaptive Mesh Refinement ◽

Mesh Refinement ◽

Adaptive Mesh ◽

Disk Galaxies ◽

Particle Hydrodynamics ◽

Smoothed Particle ◽

Temporal And Spatial ◽

Compare And Contrast

AbstractTo date, fully cosmological hydrodynamic disk simulations to redshift zero have only been undertaken with particle-based codes, such as GADGET, Gasoline, or GCD+. In light of the (supposed) limitations of traditional implementations of smoothed particle hydrodynamics (SPH), or at the very least, their respective idiosyncrasies, it is important to explore complementary approaches to the SPH paradigm to galaxy formation. We present the first high-resolution cosmological disk simulations to redshift zero using an adaptive mesh refinement (AMR)-based hydrodynamical code, in this case, RAMSES. We analyse the temporal and spatial evolution of the simulated stellar disks' vertical heating, velocity ellipsoids, stellar populations, vertical and radial abundance gradients (gas and stars), assembly/infall histories, warps/lopsideness, disk edges/truncations (gas and stars), ISM physics implementations, and compare and contrast these properties with our sample of cosmological SPH disks, generated with GCD+. These preliminary results are the first in our long-term Galactic Archaeology Simulation program.

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Influences of avalanche-defence snow-supporting structures on ground temperature in Alpine permafrost terrain

Annals of Glaciology ◽

10.3189/172756400781820336 ◽

2000 ◽

Vol 31 ◽

pp. 422-426 ◽

Cited By ~ 14

Author(s):

Marcia Phillips ◽

Perry Bartelt ◽

Marc Christen

Keyword(s):

Thermal Characteristics ◽

Temperature Measurements ◽

Finite Element Program ◽

Ground Temperatures ◽

Dimensional Finite Element ◽

Element Program ◽

Temporal And Spatial ◽

Supporting Structures ◽

Borehole Core

AbstractTo investigate the effects of steel snow-supporting structures on the thermal regime of the ground in typical Alpine permafrost avalanche terrain, ground temperatures were monitored and simulated on an avalanche slope equipped with experimental snow-supporting structures. Temperature measurements were effected in lm boreholes above and below a row of snow nets and in two 18 m boreholes located between the structures and in a reference location. The presence of the structures can induce modifications of the temporal and spatial snow-cover distribution, leading to differences in active-layer temperatures just below and above the structures: snow accumulates above the supporting surface of the structures, and frequently there is less snow below. The long-term thermal effect of these variations near a snow net was simulated using a two-dimensional finite-element program based on heat conduction. The material and thermal characteristics of the ground simulated are obtained from temperature measurements and from borehole-core information.

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