scholarly journals Reducing the impact of summer cattle grazing on water quality in the Sierra Nevada Mountains of California: a proposal

2009 ◽  
Vol 8 (2) ◽  
pp. 326-333 ◽  
Author(s):  
Robert W. Derlet ◽  
Charles R. Goldman ◽  
Michael J. Connor
Keyword(s):  
Water Quality ◽  
Sierra Nevada ◽  
Public Lands ◽  
Organic Pollution ◽  
Cattle Grazing ◽  
High Elevation ◽  
Mountain Range ◽  
Nitrogen And Phosphorus ◽  
Sierra Nevada Mountains ◽  
The Impact

The Sierra Nevada Mountain range serves as an important source of drinking water for the State of California. However, summer cattle grazing on federal lands affects the overall water quality yield from this essential watershed as cattle manure is washed into the lakes and streams or directly deposited into these bodies of water. This organic pollution introduces harmful microorganisms and also provides nutrients such as nitrogen and phosphorus which increase algae growth causing eutrophication of otherwise naturally oligotrophic mountain lakes and streams. Disinfection and filtration of this water by municipal water districts after it flows downstream will become increasingly costly. This will be compounded by increasing surface water temperatures and the potential for toxins release by cyanobacteria blooms. With increasing demands for clean water for a state population approaching 40 million, steps need to be implemented to mitigate the impact of cattle on the Sierra Nevada watershed. Compared to lower elevations, high elevation grazing has the greatest impact on the watershed because of fragile unforgiving ecosystems. The societal costs from non-point pollution exceed the benefit achieved through grazing of relatively few cattle at the higher elevations. We propose limiting summer cattle grazing on public lands to lower elevations, with a final goal of allowing summer grazing on public lands only below 1,500 m elevation in the Central and Northern Sierra and 2,000 m elevation in the Southern Sierra.

scholarly journals Impact of North Atlantic Oscillation on the Snowpack in Iberian Peninsula Mountains

Water ◽  
2019 ◽  
Vol 12 (1) ◽  
pp. 105 ◽  
Author(s):  
Esteban Alonso-González ◽  
Juan I. López-Moreno ◽  
Francisco M. Navarro-Serrano ◽  
Jesús Revuelto
Keyword(s):  
North Atlantic Oscillation ◽  
Iberian Peninsula ◽  
Sierra Nevada ◽  
North Atlantic ◽  
Snow Water Equivalent ◽  
Mountain Range ◽  
Winter Climate ◽  
Mountain Ranges ◽  
Iberian Range ◽  
The Impact

The North Atlantic Oscillation (NAO) is considered to be the main atmospheric factor explaining the winter climate and snow evolution over much of the Northern Hemisphere. However, the absence of long-term snow data in mountain regions has prevented full assessment of the impact of the NAO at the regional scales, where data are limited. In this study, we assessed the relationship between the NAO of the winter months (DJFM-NAO) and the snowpack of the Iberian Peninsula. We simulated temperature, precipitation, and snow data for the period 1979–2014 by dynamic downscaling of ERA-Interim reanalysis data, and correlated this with the DJFM-NAO for the five main mountain ranges of the Iberian Peninsula (Cantabrian Range, Central Range, Iberian Range, the Pyrenees, and the Sierra Nevada). The results confirmed that negative DJFM-NAO values generally occur during wet and mild conditions over most of the Iberian Peninsula. Due to the direction of the wet air masses, the NAO has a large influence on snow duration and the annual peak snow water equivalent (peak SWE) in most of the mountain ranges in the study, mostly on the slopes south of the main axis of the ranges. In contrast, the impact of NAO variability is limited on north-facing slopes. Negative (positive) DJFM-NAO values were associated with longer (shorter) duration and higher (lower) peak SWEs in all mountains analyzed in the study. We found marked variability in correlations of the DJFM-NAO with snow indices within each mountain range, even when only the south-facing slopes were considered. The correlations were stronger for higher elevations in the mountain ranges, but geographical longitude also explained the intra-range variability in the majority of the studied mountains.

scholarly journals Forms of Nitrogen and Phosphorus in Suspended Solids: A Case Study of Lihu Lake, China

2020 ◽  
Vol 12 (12) ◽  
pp. 5026 ◽  
Author(s):  
Jialu Li ◽  
Qiting Zuo
Keyword(s):  
Water Quality ◽  
Suspended Solids ◽  
Inorganic Phosphorus ◽  
Nitrogen And Phosphorus ◽  
Lake Ecosystems ◽  
Phosphorus Forms ◽  
Sequential Extraction Method ◽  
Main Component ◽  
The Impact

Suspended solids are an important part of lake ecosystems, and their nitrogen and phosphorus contents have a significant effect on water quality. However, information on nitrogen and phosphorus forms in suspended solids remains limited. Therefore, a case study was conducted in Lihu Lake (China), a lake with characteristically high amounts of suspended solids. Nitrogen and phosphorus speciation in suspended solids was analyzed through a sequential extraction method. We also evaluated the sources of various forms of nitrogen and phosphorus and their different effects on eutrophication. The total nitrogen (TN) content was 758.9–3098.1 mg/kg. Moreover, the proportions of various N forms in the suspended solids of the study areas were ranked as follows: Hydrolyzable nitrogen (HN) > residual nitrogen (RN) > exchangeable nitrogen (EN). Total phosphorus (TP) ranged from 294.8 to 1066.4 mg/kg, and 58.6% of this TP was inorganic phosphorus (IP). In turn, calcium (Ca)-bound inorganic phosphorus (Ca-Pi) was the main component of IP. The correlation between various nitrogen and phosphorus forms showed that there were different sources of suspended nitrogen and phosphorus throughout Lihu Lake. Correlation analysis of water quality indices and comparative analysis with surface sediments showed that in Lihu Lake, the dissolved nitrogen and phosphorus contents in water were influenced by sediment through diffusion, while particle phosphorus content in water was influenced by suspended solids through adsorption; however, due to the higher phosphorus contents in suspended solids, we should pay more attention to the impact of suspended solids.

scholarly journals The Impact of the Sierra Nevada on Low-Level Winds and Water Vapor Transport

2007 ◽  
Vol 8 (4) ◽  
pp. 790-804 ◽  
Author(s):  
Jinwon Kim ◽  
Hyun-Suk Kang
Keyword(s):  
Water Vapor ◽  
Sierra Nevada ◽  
Climate Model ◽  
Northern Region ◽  
Vapor Transport ◽  
Water Vapor Transport ◽  
Western Slope ◽  
Mountain Range ◽  
Low Level ◽  
The Impact

Abstract To understand the influence of the Sierra Nevada on the water cycle in California the authors have analyzed low-level winds and water vapor fluxes upstream of the mountain range in regional climate model simulations. In a low Froude number (Fr) regime, the upstream low-level wind disturbances are characterized by the rapid weakening of the crosswinds and the appearance of a stagnation point over the southwestern foothills. The weakening of the low-level inflow is accompanied by the development of along-ridge winds that take the form of a barrier jet over the western slope of the mountain range. Such upstream wind disturbances are either weak or nonexistent in a high-Fr case. A critical Fr (Frc) of 0.35 inferred in this study is within the range of those suggested in previous observational and numerical studies. The depth of the blocked layer estimated from the along-ridge wind profile upstream of the northern Sierra Nevada corresponds to Frc between 0.3 and 0.45 as well. Associated with these low-level wind disturbances are significant low-level southerly moisture fluxes over the western slope and foothills of the Sierra Nevada in the low-Fr case, which result in significant exports of moisture from the southern Sierra Nevada to the northern region. This along-ridge low-level water vapor transport by blocking-induced barrier jets in a low-Fr condition may result in a strong north–south precipitation gradient over the Sierra Nevada.

scholarly journals Co-optimisation of phosphorus and nitrogen removal in stormwater biofilters: the role of filter media, vegetation and saturated zone

2014 ◽  
Vol 69 (9) ◽  
pp. 1961-1969 ◽  
Author(s):  
Bonnie J. Glaister ◽  
Tim D. Fletcher ◽  
Perran L. M. Cook ◽  
Belinda E. Hatt
Keyword(s):  
Water Quality ◽  
Nutrient Removal ◽  
Phosphorus Removal ◽  
Saturated Zone ◽  
Filter Media ◽  
Nitrogen And Phosphorus ◽  
Nitrogen And Phosphorus Removal ◽  
Quality Guidelines ◽  
The Impact

Biofilters have been shown to effectively treat stormwater and achieve nutrient load reduction targets. However, effluent concentrations of nitrogen and phosphorus typically exceed environmental targets for receiving water protection. This study investigates the role of filter media, vegetation and a saturated zone (SZ) in achieving co-optimised nitrogen and phosphorus removal in biofilters. Twenty biofilter columns were monitored over a 12-month period of dosing with semi-synthetic stormwater. The frequency of dosing was altered seasonally to examine the impact of hydrologic variability. Very good nutrient removal (90% total phosphorus, 89% total nitrogen) could be achieved by incorporating vegetation, an SZ and Skye sand, a naturally occurring iron-rich filter medium. This design maintained nutrient removal at or below water quality guideline concentrations throughout the experiment, demonstrating resilience to wetting–drying fluctuations. The results also highlighted the benefit of including an SZ to maintain treatment performance over extended dry periods. These findings represent progress towards designing biofilters which co-optimise nitrogen and phosphorus removal and comply with water quality guidelines.

scholarly journals Remediation of Nitrogen and Phosphorus from Nursery Runoff during the Spring via Free Water Surface Constructed Wetlands

2010 ◽  
Vol 28 (4) ◽  
pp. 209-217 ◽  
Author(s):  
Sarah A. White ◽  
Milton D. Taylor ◽  
Stewart L. Chandler ◽  
Ted Whitwell ◽  
Stephen J. Klaine
Keyword(s):  
Water Quality ◽  
Water Surface ◽  
Nutrient Loading ◽  
Free Water ◽  
Surface Water Quality ◽  
Phosphorus Loading ◽  
Late Winter ◽  
Nitrogen And Phosphorus ◽  
Free Water Surface ◽  
The Impact

Abstract Agricultural operations face increasing pressure to remediate runoff to reduce deterioration of surface water quality. Some nursery operations use free water surface constructed wetland systems (CWSs) to remediate nutrient-rich runoff. Our objectives were twofold, first to examine the impact of two hydraulic retention times (HRT, 3.5 and 5.5 day) on CWS performance, and second to determine if increased nutrient loading from internal CWS and nursery sources during the spring contributed to nutrient export in excess of regulatory limits. We quantified nutrient loading and removal efficiency in a free water surface CWS from late winter through late spring over three years and monitored various water quality parameters. Total nitrogen in runoff was reduced from 20.6 ± 2.8 mg·liter−1 (ppm) to 4.1 ± 1.3 mg·liter−1 (ppm) nitrogen after CWS treatment. Phosphorus dynamics in the CWS were more variable and unlike nitrogen dynamics were not consistently influenced by water temperature and hydraulic loading rate. Phosphorus concentrations were reduced from 1.7 ± 0.8 mg·liter−1 (ppm) PO4-P in influent to 1.2 ± 0.6 mg·liter−1 (ppm) PO4-P in CWS effluent, but substantial variability existed among years in both phosphorus loading and removal rates. The CWS was able to efficiently remediate nitrogen even under high spring loading rates.

One Hundred Years of Solitude: rediscovery of Catasticta lycurgus (Godman & Salvin, 1880), a yellow butterfly from the Sierra Nevada de Santa Marta, Colombia (Lepidoptera: Pieridae)

Zootaxa ◽  
2021 ◽  
Vol 4975 (1) ◽  
pp. 176-186
Author(s):  
BLANCA HUERTAS ◽  
CARLOS PRIETO ◽  
FREDY MONTERO ◽  
MIKE ADAMS ◽  
JEAN FRANÇOIS LE CROM ◽  
...  
Keyword(s):  
Sierra Nevada ◽  
High Elevation ◽  
Mountain Range ◽  
Conservation Assessment ◽  
The North ◽  
The Andes ◽  
San Pedro ◽  
Systematic Relationships ◽  
The Uk ◽  
First Time

Catasticta lycurgus is a striking endemic butterfly, restricted to high elevation habitats in the Sierra Nevada de Santa Marta, an isolated mountain range separate from the Andes in the north of Colombia. The type, which for almost a hundred years was the only known specimen, was collected in 1878 by Frederick Simons in the vicinity of Atánquez and was sent to the UK to be described by renowned naturalists Godman and Salvin in 1880. In 1972, explorers Adams and Bernard collected a second specimen of C. lycurgus in the locality of San Pedro at 2,900m of elevation in the Sierra Nevada de Santa Marta. These two specimens were the only known ones for many decades until recently, when Colombian entomologists found the species again in San Pedro de la Sierra and later, when a female was discovered in 2013. Here, we report the rediscovery of this rare and charismatic species, with new specimens collected near the type locality, which have not been reported previously. The female of C. lycurgus is described and illustrated for the first time as well the male genitalia of this species. We combine all information available to provide some insights on the systematic relationships of this species within the genus Catasticta Butler, discuss its distribution and provide a preliminary conservation assessment. Despite the newly collected specimens, the species remains very rare in the field and in collections. 

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