Nutrient survey of surface waters in southern Florida during a wet and a dry season, September 1970 and March 1971

1972 ◽  
Author(s):  
Herbert J. Freiberger
2021 ◽  
Author(s):  
Sara E. Gallego Ríos ◽  
Gustavo A. Peñuela

Abstract This is one of the first studies carried out over three climatic seasons on the determination of ibuprofen and diclofenac, in the main rivers of Colombia and striped catfish Pseudoplatystoma magdaleniatum. Determination of water concentrations was carried out using SPE extraction, while for the analysis of the muscular tissue the extraction was carried out by QuEChERS. For both matrices, quantification was done by UHPLC-MS/MS. No levels of ibuprofen or diclofenac concentrations were found in muscle tissue of Pseudoplatystoma magdaleniatum, in any season or sampling site, during the two years of sampling. In some sampling sites, concentrations of up to 75 µg/L of diclofenac were detected, corresponding to the sampling carried out in the dry season, being the highest reported so far in surface waters, possibly generated by large concentrations of population or agricultural activities. On the other hand, for ibuprofen, no concentrations above the limit of quantification (0.50 µg/L) were found in the waters of the Cauca and Magdalena rivers, for any season and sampling site.


Water ◽  
2020 ◽  
Vol 12 (9) ◽  
pp. 2453
Author(s):  
Zheyue Zhang ◽  
Jihong Qin ◽  
Hui Sun ◽  
Jiyuan Yang ◽  
Yanyang Liu

The concentrations of dissolved organic carbon (DOC) and its light-absorbing fraction (chromophoric dissolved organic matter; CDOM) in surface waters, particularly those draining organic-rich peatlands, have dramatically increased over the past decade due to climate change and human disturbance. To explore the spatiotemporal dynamics of DOC and CDOM in surface waters of the northeastern Qinghai-Tibetan Plateau, we collected water samples from two rivers in the Zoige alpine wetland and from two rivers in its adjacent alpine-gorge region, during wet and dry seasons. DOC concentration ranged from 4.82 mg·L−1 to 47.83 mg·L−1, with a mean value of 15.04 mg·L−1, 2.84 times higher than the global average. The Zoige rivers had higher DOC concentration and highly terrigenous CDOM. Significantly higher DOC concentration was observed for the Zoige rivers in the wet season compared to the dry season. In contrast, the alpine-gorge rivers had higher DOC levels in the dry season. No significant correlations were observed between DOC and CDOM at all rivers due to the influence of autochthonous sources on the alpine-gorge rivers and intensive photochemical degradation of terrigenous DOM in the Zoige rivers. Significant relationships between CDOM and specific ultraviolet absorbance at 254 nm (SUVA254) and between CDOM/DOC and SUVA254 were observed, indicating that the aromaticity of DOM in the rivers was mainly determined by CDOM. Moreover, the DOC/CDOM properties of the Hei River indicate critical human-induced water quality degradation. High DOC level and high browning degree were found in rivers in the Zoige alpine wetland, indicating that large amounts of terrigenous DOC were released to the aquatic systems of the region.


2004 ◽  
Vol 14 (4) ◽  
pp. 545-550 ◽  
Author(s):  
Chris Wilson ◽  
Ed Stover ◽  
Brian Boman

Off-target deposition of pesticidal spray material is both an economic loss to the grower and a potential environmental problem in southern Florida. This study evaluated the reduction in non-target deposition of copper resulting from different approaches to spraying row-ends in typical Indian River citrus (Citrus) production systems. Using copper as a model pesticide, applications were made in a commercial citrus grove in June and July 2001. Non-target deposition on the water surface within an adjacent drainage canal, as well as on surrounding ground surfaces, was measured using Teflon spray targets. Specific row-end spraying scenarios included: 1) leaving both banks of nozzles on while turning; 2) turning the outside-facing nozzles off (leaving tree-facing nozzles on); 3) turning both banks of nozzles off at the tree trunk; and 4) turning all nozzles off at the end of the foliage of the last tree within the row. Deposition directly onto surface water contained within drainage canals was reduced significantly when nozzles were turned off at the last tree within a row, or when the outside-facing nozzles-only were turned off through the turn. Likewise, deposition was reduced on ground surfaces adjacent to the sprayer under the same scenarios. No differences were observed on ground surfaces on the opposite side of the canal. Significant reductions in direct application of agrichemicals to surface waters within Indian River citrus production groves can be achieved by turning nozzles off when turning from one tree row into the next.


1985 ◽  
Vol 6 (2) ◽  
pp. 52-58 ◽  
Author(s):  
Susan T. Bagley

AbstractThe genus Klebsiella is seemingly ubiquitous in terms of its habitat associations. Klebsiella is a common opportunistic pathogen for humans and other animals, as well as being resident or transient flora (particularly in the gastrointestinal tract). Other habitats include sewage, drinking water, soils, surface waters, industrial effluents, and vegetation. Until recently, almost all these Klebsiella have been identified as one species, ie, K. pneumoniae. However, phenotypic and genotypic studies have shown that “K. pneumoniae” actually consists of at least four species, all with distinct characteristics and habitats. General habitat associations of Klebsiella species are as follows: K. pneumoniae—humans, animals, sewage, and polluted waters and soils; K. oxytoca—frequent association with most habitats; K. terrigena— unpolluted surface waters and soils, drinking water, and vegetation; K. planticola—sewage, polluted surface waters, soils, and vegetation; and K. ozaenae/K. rhinoscleromatis—infrequently detected (primarily with humans).


Author(s):  
James S. Webber

INTRODUCTION“Acid rain” and “acid deposition” are terms no longer confined to the lexicon of atmospheric scientists and 1imnologists. Public awareness of and concern over this phenomenon, particularly as it affects acid-sensitive regions of North America, have increased dramatically in the last five years. Temperate ecosystems are suffering from decreased pH caused by acid deposition. Human health may be directly affected by respirable sulfates and by the increased solubility of toxic trace metals in acidified waters. Even man's monuments are deteriorating as airborne acids etch metal and stone features.Sulfates account for about two thirds of airborne acids with wet and dry deposition contributing equally to acids reaching surface waters or ground. The industrial Midwest is widely assumed to be the source of most sulfates reaching the acid-sensitive Northeast since S02 emitted as a byproduct of coal combustion in the Midwest dwarfs S02 emitted from all sources in the Northeast.


EDIS ◽  
2017 ◽  
Vol 2017 (6) ◽  
Author(s):  
Rebecca L. Wente ◽  
Samuel F. Hutton ◽  
Scott Adkins ◽  
William Turechek ◽  
Joseph E. Funderburk

Authors describe performance of Tospovirus-resistant tomato varieties under commercial production settings in Dade County, FL. Virus resistance has become important for this area since the emergence of two new tomato-infecting tospoviruses. Knowledge of availability and performance of resistant varieties will help growers who are looking for alternative varieties.


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