scholarly journals An Eighteen Year Temporal Trends Analysis of Bifenthrin Sediment Concentrations in California Waterbodies

Water ◽  
2020 ◽  
Vol 12 (9) ◽  
pp. 2402
Author(s):  
Lenwood W. Hall ◽  
Ronald D. Anderson

The goal of this study was to conduct long-term temporal trends analysis of bifenthrin sediment concentrations for measurements conducted from 2001 to 2019 in California waterbodies. Long-term data sites defined as spanning 6 years were available for 143 sites but 17 of these sites were excluded from long analysis because all measurements were below the level of detection. At least one site used in the trends analysis was located in all nine California Water Board Regions thus providing a representative statewide spatial scale. Twenty of the 126 long-term California sediment sites showed a statistically significant downward trend in bifenthrin concentrations while nine sites showed a statistically significant upward trend. Declining bifenthrin sediment concentrations were most evident in urban waterbodies when compared with agricultural dominated waterbodies. An analysis of bifenthrin long-term sediment trends by waterbody with at least three sites showed a significant trend for only one residential/urban stream and this trend was declining. In summary, the trends analysis of bifenthrin sediment concentrations does show a compelling case for declining concentrations in the State of California during an 18-year time period that includes a time period before and after the urban use of bifenthrin was further regulated.

2019 ◽  
Author(s):  
Miho Ishizu ◽  
Yasumasa Miyazawa ◽  
Tomohiko Tsunoda ◽  
Tsuneo Ono

Abstract. In recent decades, acidification of the open ocean has shown consistent increases. However, analysis of long-term data in coastal waters shows that the pH is highly variable because of coastal processes and anthropogenic carbon inputs. It is therefore important to understand how anthropogenic carbon inputs and other natural or anthropogenic factors influence the temporal trends in pH in coastal waters. Using water quality data collected at 1481 monitoring sites as part of the Water Pollution Control Program, we determined the long-term trends in pH in Japanese coastal waters at ambient temperature from 1978 to 2009. We found that pH decreased (i.e., acidification) at between 70 % and 75 % of the sites and increased (i.e., basification) at between 25 % and 30 % of the sites. The rate of decrease varied seasonally and was, on average, −0.0014 yr−1 in summer and −0.0024 yr−1 in winter, but with relatively large deviations from these average values. While the overall trends reflect acidification, watershed processes might also have contributed to the large variations in pH in coastal waters. The seasonal variation in the average pH trends reflects variability in warming trends, while regional differences in pH trends are partly related to heterotrophic water processes induced by nutrient loadings.


Fire ◽  
2021 ◽  
Vol 4 (4) ◽  
pp. 74
Author(s):  
Gonzalo Otón ◽  
José Miguel C. Pereira ◽  
João M. N. Silva ◽  
Emilio Chuvieco

We present an analysis of the spatio-temporal trends derived from long-term burned area (BA) data series. Two global BA products were included in our analysis, the FireCCI51 (2001–2019) and the FireCCILT11 (1982–2018) datasets. The former was generated from Moderate Resolution Imaging Spectroradiometer (MODIS) 250 m reflectance data, guided by 1 km active fires. The FireCCILT11 dataset was generated from Land Long-Term Data Record data (0.05°), which provides a consistent time series for Advanced Very High Resolution Radiometer images, acquired from the NOAA satellite series. FireCCILT11 is the longest time series of a BA product currently available, making it possible to carry out temporal analysis of long-term trends. Both products were developed under the FireCCI project of the European Space Agency. The two datasets were pre-processed to correct for temporal autocorrelation. Unburnable areas were removed and the lack of the FireCCILT11 data in 1994 was examined to evaluate the impact of this gap on the BA trends. An analysis and comparison between the two BA products was performed using a contextual approach. Results of the contextual Mann-Kendall analysis identified significant trends in both datasets, with very different regional values. The long-term series presented larger clusters than the short-term ones. Africa displayed significant decreasing trends in the short-term, and increasing trends in the long-term data series, except in the east. In the long-term series, Eastern Africa, boreal regions, Central Asia and South Australia showed large BA decrease clusters, and Western and Central Africa, South America, USA and North Australia presented BA increase clusters.


2021 ◽  
Vol 13 (12) ◽  
pp. 5867-5877
Author(s):  
Brian R. MacKenzie ◽  
Teresa Romeo ◽  
Piero Addis ◽  
Pietro Battaglia ◽  
Pierpaolo Consoli ◽  
...  

Abstract. Management of marine fisheries and ecosystems is constrained by knowledge based on datasets with limited temporal coverage. Many populations and ecosystems were perturbed long before scientific investigations began. This situation is particularly acute for the largest and commercially most valuable species. We hypothesized that historical trap fishery records for bluefin tuna (Thunnus thynnus Linnaeus, 1758) could contain catch data and information for other, bycatch species, such as swordfish (Xiphias gladius Linnaeus, 1758). This species has a long history of exploitation and is presently overexploited, yet indicators of its status (biomass) used in fishery management only start in 1950. Here we examine historical fishery records and logbooks from some of these traps and recovered ca. 110 years of bycatch data (1896–2010). These previously neglected, but now recovered, data include catch dates and amounts in numbers and/or weights (including individual weights) for the time period before and after major expansion of swordfish fisheries in the Mediterranean Sea. New historical datasets such as these could help understand how human activities and natural variability interact to affect the long-term dynamics of this species. The datasets are online and available with open access via three DOIs, as described in the “Data availability” section of the article.


2021 ◽  
Author(s):  
Brian R. MacKenzie ◽  
Teresa Romeo ◽  
Piero Addis ◽  
Pietro Battaglia ◽  
Pierpaolo Consoli ◽  
...  

Abstract. Management of marine fisheries and ecosystems is constrained by knowledge based on datasets with limited temporal coverage. Many populations and ecosystems have been perturbed long before scientific investigations have begun. This situation is particularly acute for the largest and commercially most valuable species. We hypothesized that historical trap fishery records for bluefin tuna, Thunnus thynnus, could contain catch data and information for other, bycatch species, such as swordfish, Xiphias gladius. This species has a long history of exploitation and is presently overexploited, yet indicators of its status (biomass) used in fishery management only start in 1950. Here we examine historical fishery records and logbooks from some of these traps and recovered ca. 110 years of bycatch data (1896–2010). These previously-neglected, but now recovered, data include catch dates and amounts in numbers and/or weights (including individual weights) for the time period before and after major expansion of swordfish fisheries in the Mediterranean Sea. New historical datasets such as these could help understand how human activities and natural variability interact to affect long-term dynamics of this species.


2020 ◽  
Vol 38 (6_suppl) ◽  
pp. 400-400
Author(s):  
Xiaosong Meng ◽  
Hersh Trivedi ◽  
Alexander P. Kenigsberg ◽  
Rashed Ghandour ◽  
Vitaly Margulis ◽  
...  

400 Background: Medicaid Expansion (ME) was introduced by the Affordable Care Act to improve access to care for low income individuals by increasing the annual income limits to 138% of the poverty line. However, not all states have elected to participate in ME. Using the National Cancer Database (NCDB), we sought to assess the effects of participation in ME on the four most common urologic malignancies. Methods: The NCDB was queried for bladder, prostate, kidney and testis cancer from 2012-2016, to span the time period two years before and two years after the main ME which took place in 2014. Trends in insurance status at time of diagnosis and effects on stage at presentation before and after ME were analyzed. Results: The percentage of patients with Medicaid coverage at the time of diagnosis for all four urologic malignancies increased significantly after 2014, with a commiserate decrease in the percentage of uninsured patients (Table). By 2016, significantly more patients had Medicaid coverage at diagnosis in ME states compared to those in Non-ME states (bladder 5.0% vs 2.5%, prostate 5.9% vs 2.2%, kidney 9.7% vs 4.1%, 19.5% vs 7.2%, all p < 0.01). However, the stage at presentation for all four urologic malignancies did not significantly differ for patients in ME versus non-ME states. Conclusions: Despite an increase in the proportion of patients with Medicaid coverage after 2014, surprisingly, there was not an associated change in stage at presentation for urologic malignancies in ME states. Further long-term analysis is necessary to evaluate if expanded Medicaid coverage impacts overall survival in this patient population.[Table: see text]


2020 ◽  
Vol 77 (4) ◽  
pp. 268-275 ◽  
Author(s):  
Hicham Zilaout ◽  
Remko Houba ◽  
Hans Kromhout

ObjectivesSince 2000 the European Industrial Minerals Association’s Dust Monitoring Programme (IMA-DMP) has systematically collected respirable dust and respirable quartz measurements from 35 companies producing industrial minerals. The IMA-DMP initiative allowed for estimating overall temporal trends in exposure concentrations for the years 2002–2016 and for presenting these trends by type of mineral produced, by jobs performed and by time of enrolment into the DMP.MethodsApproximately 32 000 personal exposure measurements were collected during 29 sampling campaigns during a 15-year period (2002–2016). Temporal trends in respirable dust and respirable quartz concentrations were studied by using linear mixed effects models.ResultsConcentrations varied widely (up to three to four orders of magnitude). However, overall decreases in exposure levels were shown for the European minerals industry over the 15-year period. Statistically significant overall downward temporal trends of −9.0% and −3.9% per year were observed for respirable dust and respirable quartz, respectively. When analyses were stratified by time period, no downward trends (and even slight increasing concentrations) were observed between 2008 and 2012, most likely attributable to the recent global economic crisis. After this time period, downward trends became visible again.ConclusionsConsistent and statistically significant downward trends were found for both exposure to respirable dust and respirable quartz. These downward trends became less or even reversed during the years of the global economic crisis. To our knowledge, this is the first time that analyses of long-term temporal trends point at an effect of a global economic crisis on personal exposure concentrations of workers from sites across Europe.


2019 ◽  
Vol 10 (2) ◽  
pp. 602-618
Author(s):  
Mark J. Fincel ◽  
Nicholas B. Kludt ◽  
Hilary A. Meyer ◽  
Michael Weber ◽  
Christopher M. Longhenry

Abstract Sauger Sander canadensis, Walleye Sander vitreus, and Smallmouth Bass Micropterus dolomieu, are important sportfish in the four main stem Missouri River reservoirs in South Dakota: Lakes Oahe, Sharpe, Francis Case, and Lewis and Clark. However, native Sauger populations, once assumed to be stable, may be in decline. To identify temporal trends and potential interspecific mechanisms affecting Sauger populations, we examined their long-term abundance trends in standard gillnet surveys and angler catch and harvest trends in long-term creel surveys. We also used a robust design occupancy model to examine changes in within-lake distribution of this species. There are concerns regarding the effects of Walleye and Smallmouth Bass on Sauger, so we also described the population trends of these potential competitors. Standard gillnet surveys indicated declining abundance of both Sauger and Walleye in Lakes Oahe and Sharpe. Sauger abundance has trended down in Lewis and Clark, but upward in Francis Case. Conversely, Walleye abundance trends declined in Francis Case and increased in Lewis and Clark. Occupancy (ψ̂) of Sauger declined in all four reservoirs, indicating a contracting distribution throughout the reservoirs. Walleye occupancy remained ∼1.0. Smallmouth Bass occupancy increased in the three reservoirs with sufficient data for analysis, excluding Lewis and Clark Lake. Smallmouth Bass exhibited steady increases in angler catch and harvest, as well as abundance in long-term gillnet surveys, suggesting expanding and increasing populations. Habitat alteration is hypothesized to be a major driver of the Sauger occupancy and abundance declines. However, Walleye and Smallmouth Bass interactions could also be contributing to observed declines of native Sauger.


1997 ◽  
Vol 48 (8) ◽  
pp. 759 ◽  
Author(s):  
William F. Herrnkind ◽  
Mark J. Butler IV ◽  
John H. Hunt ◽  
Michael Childress

In 1991 and 1992, cyanobacterial blooms depleted sponges, the primary refuge of juvenile Caribbean spiny lobsters, in ~20% of the nursery in the Florida Keys, USA. Long-term data from the affected middle Keys were used to study the impact of sponge loss, juvenile abundance, recruitment and shelter use. A manipulative experiment (1991–93) involved artificial shelters on 27 ~0.5-h sites. Conditions on 19 sites over the affected ~ 500 km 2 area were compared before and after the blooms. The entire nursery (~10,000 km2) was surveyed to estimate the impact of the disturbance on total juvenile recruitment. Refuge and lobster abundances declined and the pattern of shelter use changed on previously sponge- rich sites without alternative shelter (solution holes, coral heads, cement blocks, etc.). Although sponge loss often locally reduced juvenile abundance, the juvenile lobster population overall declined by ~5%. The availability of alternative, previously underused shelter (solution holes, coral heads, etc.) in the affected region, continued production in the larger unaffected nursery region, and high postlarval supply that fortuitously coincided with sponge loss all offset a stronger effect. However, postlarval supply is unlikely to remain high until the sponges repopulate the middle Keys (10+ years), so a major factor ameliorating the effect of sponge loss on lobster recruitment may disappear.


Author(s):  
K. Szentteleki ◽  
M. Gaál ◽  
M. Ladányi

Long term data of hail events of three meteorological stations (Budapest, Debrecen and Szeged) were investigated. The hail event frequencies show significant differences in the time period 1901–2000 when the first and the second half of the century are compared. The frequencies of hail events are higher in the first half of the century in case of Debrecen and Szeged while it is higher in the second 50 years for Budapest. None of the frequencies of hail events in between 2001–2008 are significantly higher, though the average of precipitation fell during these events is higher except for Szeged. We have found that the results about the monthly distribution of hail events differ from the ones in the literature; the ratio of hail events is significantly less in the vegetation period.


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