Classifying California’s stream thermal regimes for cold-water conservation

Stream temperature science and management is rapidly shifting from single-metric driven approaches to multi-metric, thermal regime characterizations of streamscapes. Given considerable investments in recovery of cold-water fisheries (e.g., Pacific salmon and other declining native species), understanding where cold water is likely to persist, and how cold-water thermal regimes vary, is critical for conservation. California’s unique position at the southern end of cold-water ecosystems in the northern hemisphere, variable geography and hydrology, and extensive flow regulation requires a systematic approach to thermal regime classification. We used publicly available, long-term (> 8 years) stream temperature data from 77 sites across California to model their thermal regimes, calculate three temperature metrics, and use the metrics to classify each regime with an agglomerative nesting algorithm. Then, we assessed the variation in each class and considered underlying physical or anthropogenic factors that could explain differences between classes. Finally, we considered how different classes might fit existing criteria for cool- or cold-water thermal regimes, and how those differences complicate efforts to manage stream temperature through regulation. Our results demonstrate that cool- and cold-water thermal regimes vary spatially across California. Several salient findings emerge from this study. Groundwater-dominated streams are a ubiquitous, but as yet, poorly explored class of thermal regimes. Further, flow regulation below dams imposes serial discontinuities, including artificial thermal regimes on downstream ecosystems. Finally, and contrary to what is often assumed, California reservoirs do not contain sufficient cold-water storage to replicate desirable, reach-scale thermal regimes. While barriers to cold-water conservation are considerable and the trajectory of cold-water species towards extinction is dire, protecting reaches that demonstrate resilience to climate warming remains worthwhile.

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Effects of land use on summer thermal regimes in critical salmonid habitats of the Pacific Northwest

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/cjfas-2018-0165 ◽

2019 ◽

Vol 76 (5) ◽

pp. 753-761 ◽

Cited By ~ 3

Author(s):

Ryan P. Kovach ◽

Clint C. Muhlfeld ◽

Robert Al-Chokhachy ◽

Jeffrey V. Ojala ◽

Eric K. Archer

Keyword(s):

Climate Change ◽

Pacific Northwest ◽

Land Management ◽

Management Practices ◽

Cold Water ◽

Stream Temperature ◽

Livestock Grazing ◽

Temperature Regimes ◽

Thermal Regimes ◽

Conservation Concern

The effect of climate change on stream temperature regimes is of significant concern to natural resource managers focused on protecting cold-water-dependent species. Nevertheless, understanding of how human land-use activities may act to exacerbate the effects of climate change on stream temperature regimes is limited. Using extensive stream temperature data with high-resolution climate and habitat data, we quantified how land management activities are related to summer stream temperatures across the Pacific Northwest, USA. We then described the distribution of land management practices influencing summer thermal regimes relative to the distribution of salmonid fish species of conservation concern. After accounting for climatic and geophysical variation, we detected a strong relationship between livestock grazing and summer thermal regimes. Maximum, average, and diel variation in water temperature was greater where livestock grazing was present. Livestock grazing was widespread, occurring in 43%–100% of sites supporting salmonid species of conservation concern. Thus, current land management practices may be intensifying the effects of ongoing climate change in freshwater habitats, acting to further threaten cold-water fishes of conservation concern.

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Phytoplankton of cold-water lake ecosystems under the influence of natural and anthropogenic factors

Issues of modern algology (Вопросы современной альгологии) ◽

10.33624/2311-0147-2021-1(21)-42-49 ◽

2021 ◽

pp. 42-49

Author(s):

Andrey N. Sharov

Keyword(s):

Heavy Metals ◽

Cold Water ◽

Arctic Lakes ◽

Water Bodies ◽

The Arctic ◽

Anthropogenic Factors ◽

Large Lakes ◽

Arctic Water ◽

The North ◽

Natural And Anthropogenic Factors

Based on the study of the spatio-temporal aspects of the development of phytoplankton in the lakes of the North and North-West of the European territory of Russia (large lakes – Imandra, Onega and Chudsko-Pskovskoye and small lakes of the Arctic and Subarctic), the features of its structure and dynamics under the influence of natural and anthropogenic factors (eutrophication, heavy metal pollution, acidification, thermification). The species composition and quantitative characteristics of phytoplankton of large lakes of the North of Russia, small arctic lakes and lakes of subarctic regions are studied. It has been shown that diatoms predominate in arctic water bodies according to species diversity, and green and diatoms predominate in boreal ones. By biomass, diatoms dominate mainly in all cold-water lakes, with the exception of small arctic lakes, where golden algae lead. The features of the reorganization of phytoplankton in response to the action of anthropogenic factors are revealed. It is proved that in the northern water bodies the complex action of heavy metals and nutrients does not lead to inhibition of phytoplankton, and the effect of acidification in combination with heavy metals enhances the toxic effect of the latter. A feature of the response to acidification is an increase in the variability of the dynamics of the biomass of phytoplankton. It has been shown that in different types of lakes of East Antarctica under severe climate conditions under light and biogenic limitation, redistribution of autotrophic components in the formation of the biota of water bodies occurs: against the background of a decrease in the abundance and diversity of phytoplankton, the role of microphytobenthos and periphyton increases.

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pH up-regulation as a potential mechanism for the cold-water coral Lophelia pertusa to sustain growth in aragonite undersaturated conditions

Biogeosciences ◽

10.5194/bg-12-6869-2015 ◽

2015 ◽

Vol 12 (23) ◽

pp. 6869-6880 ◽

Cited By ~ 17

Author(s):

M. Wall ◽

F. Ragazzola ◽

L. C. Foster ◽

A. Form ◽

D. N. Schmidt

Keyword(s):

Deep Water ◽

Cold Water ◽

Isotope Analysis ◽

Lophelia Pertusa ◽

Ambient Seawater ◽

Skeletal Morphology ◽

Composition And Structure ◽

Ph Conditions ◽

Water Ecosystems ◽

Water Coral

Abstract. Cold-water corals are important habitat formers in deep-water ecosystems and at high latitudes. Ocean acidification and the resulting change in aragonite saturation are expected to affect these habitats and impact coral growth. Counter to expectations, the deep water coral Lophelia pertusa has been found to be able to sustain growth even in undersaturated conditions. However, it is important to know whether such undersaturation modifies the skeleton and thus its ecosystem functioning. Here we used Synchrotron X-Ray Tomography and Raman spectroscopy to examine changes in skeleton morphology and fibre orientation. We combined the morphological assessment with boron isotope analysis to determine if changes in growth are related to changes in control of calcification pH. We compared the isotopic composition and structure formed in their natural environment to material grown in culture at lower pH conditions. Skeletal morphology is highly variable but shows no distinctive differences between natural and low pH conditions. Raman investigations found no difference in macromorphological skeletal arrangement of early mineralization zones and secondary thickening between the treatments. The δ11B analyses show that L. pertusa up-regulates the internal calcifying fluid pH (pHcf) during calcification compared to ambient seawater pH and maintains a similar elevated pHcf at increased pCO2 conditions. We suggest that as long as the energy is available to sustain the up-regulation, i.e. individuals are well fed, there is no detrimental effect to the skeletal morphology.

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Evaluation of factors that affect the spatial distribution of alien shrubs to monitor their invasion in a Pampa protected landscape in Tandil, Argentina

Revista Brasileira de Gestão Ambiental e Sustentabilidade ◽

10.21438/rbgas.061312 ◽

2019 ◽

Vol 6 (13) ◽

pp. 427-444

Author(s):

María Isabel Márquez ◽

María Julia Kristensen ◽

Juan Manuel Lavornia ◽

Santiago Linares

Keyword(s):

Information System ◽

Geographical Information System ◽

Native Species ◽

Unsupervised Classification ◽

Geographical Information ◽

Anthropogenic Factors ◽

Mountainous Area ◽

Explanatory Variables ◽

Spontaneous Vegetation ◽

Global Threat

Invasive alien plants which replace native species represent a global threat that compromises biodiversity conservation by simplifying and homogenizing the landscape. The present study focuses on the problem of invasions in a mountainous area of the pampas (Tandil, Argentina) where several alien shrubs behave as invaders displacing a high diversity of native grassland. The aim of the study was to analyze, by means of geographical information system, the distribution of the most conspicuous alien shrub populations in relation to natural and anthropogenic factors in a protected area of landscape of the pampa region, in order to contribute to decision making and management based on knowledge. The selected working areas were those with spontaneous vegetation, conducting unsupervised classification of SPOT satellite images. A number of points in invaded areas were georeferenced in field to control the classification made by geographical information system. To measure the influence of the factors analyzed in the dispersal processes of the species spatial logistic regression techniques were used. Results showed that 20.40% of the study area was occupied by alien species of which 11.06% were tree plantations made by man and 9.34% corresponded to three alien shrub species distributed invading different landscape sections: Genista monspesullana occupied 307.85 ha, Rubus ulmifolius 237.82 ha and Spartium junceum 126.55 ha. In order to explain R. ulmifolius propagation all the analysed variables except quarries and pits were significant, but streets, roads and trails and stone fences had a stronger incidence. For S. junceum the significant explanatory variables were quarries and pits, altitude and slope. For G. monspesullana the explanatory variable was streets, roads and trails.

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A New Thermal Categorization of Ice-covered Lakes

10.5194/egusphere-egu21-923 ◽

2021 ◽

Author(s):

Bernard Yang ◽

Mathew Wells ◽

Bailey McMeans ◽

Hilary Dugan ◽

James Rusak ◽

...

Keyword(s):

Temperature Profile ◽

Water Column ◽

Wind Stress ◽

Thermal Regime ◽

Thermal Stratification ◽

Trophic Status ◽

Cold Water ◽

Entire Water Column ◽

Lake Type

Lakes are traditionally classified based on their thermal regime and trophic status. While this classification adequately captures many lakes, it is not sufficient to understand seasonally ice-covered lakes, the most common lake type on Earth. We describe the inverse thermal stratification in 19 highly varying lakes and derive a model that predicts the temperature profile as a function of wind stress, area, and depth. The results suggest an additional subdivision of seasonally ice-covered lakes to differentiate under-ice stratification. When ice forms in smaller and deeper lakes, inverse stratification will form with a thin buoyant layer of cold water (near 0oC) below the ice, which remains above a deeper 4oC layer. In contrast, the entire water column can cool to ~0oC in larger and shallower lakes. We suggest these alternative conditions for dimictic lakes be termed &#8220;cryostratified&#8221; and &#8220;cryomictic.&#8221;

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The interactive effects of stream temperature, stream size, and non-native species on Yellowstone cutthroat trout

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/cjfas-2020-0408 ◽

2021 ◽

Author(s):

Robert Al-Chokhachy ◽

Mike Lien ◽

Bradley B. Shepard ◽

Brett High

Keyword(s):

Native Species ◽

Cutthroat Trout ◽

Population Level ◽

Stream Temperature ◽

Interactive Effects ◽

Oncorhynchus Clarkii ◽

Wide Range ◽

Yellowstone Cutthroat Trout ◽

Stream Size ◽

Native Salmonids

Climate change and non-native species are considered two of the biggest threats to native salmonids in North America. We evaluated how non-native salmonids and stream temperature and discharge were associated with Yellowstone cutthroat trout (Oncorhynchus clarkii bouvieri) distribution, abundance, and body size, to gain a more complete understanding of the existing threats to native populations. Allopatric Yellowstone cutthroat trout were distributed across a wide range of average August temperatures (3.2 to 17.7ºC), but occurrence significantly declined at colder temperatures (<10 ºC) with increasing numbers of non-natives. At warmer temperatures occurrence remained high, despite sympatry with non-natives. Yellowstone cutthroat trout relative abundance was significantly reduced with increasing abundance of non-natives, with the greatest impacts at colder temperatures. Body sizes of large Yellowstone cutthroat trout (90th percentile) significantly increased with warming temperatures and larger stream size, highlighting the importance of access to these more productive stream segments. Considering multiple population-level attributes demonstrates the complexities of how native salmonids (such as Yellowstone cutthroat trout) are likely to be affected by shifting climates.

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ZOOBENTHOS OF WATERCOURSES IN THE BUKHTARMA RIVER BASIN (UPPER IRTYSH, SOUTH-WESTERN ALTAI) AT REFERENCE SITES AND IN THE IMPACT ZONE

Transactions of Papanin Institute for Biology of Inland Waters RAS ◽

10.47021/0320-3557-2021-66-83 ◽

2021 ◽

pp. 66-83

Author(s):

A. Evseeva

Keyword(s):

River Basin ◽

Cold Water ◽

Taxonomic Composition ◽

Anthropogenic Factors ◽

Impact Zone ◽

High Oxygen Content ◽

Water Courses ◽

Cold Water Temperature ◽

Composition Structure ◽

The Impact

The composition, structure, and spatial distribution of zoobenthos in streams of the Bukhtarma River basin are described and quantitative indicators of benthos in the lower course of the Bukhtarma River are given. The predominance of insects from the orders of mayflies, caddisflies, and freckles is characteristic of the water-courses in the Bukhtarma River basin and is associated with the presence of stony soils in the rivers, rapid flow, moderate-cold-water temperature regime, and high oxygen content in the water – factors that are most favorable for these groups of invertebrates. To assess the ecological state of surface waters in the streams under study by bioindication methods, TBI, BMWP, ASPT, and ERT biotic indices are used. The taxonomic composition of each of the studied watercourses and river sections is formed in accordance with specific environmental conditions associated with natural and anthropogenic factors. It is established that watercourses in the reference areas can be used as reference ones in accordance with the requirements of the EU Framework Water Directive, and the characteristics of invariant States of biocenoses of the lower course of the Bukhtarma River in the impact zone are also given using the criteria of the V. A. Abakumov system of ecological modulations.

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Evolution of the grapevine bud dormancy under different thermal regimes

Semina Ciências Agrárias ◽

10.5433/1679-0359.2019v40n6supl3p3419 ◽

2019 ◽

Vol 40 (6Supl3) ◽

pp. 3419

Author(s):

Rafael Anzanello

Keyword(s):

High Temperature ◽

Thermal Regime ◽

Heat Waves ◽

Bud Dormancy ◽

Southern Brazil ◽

Thermal Requirements ◽

Thermal Regimes ◽

Negative Effect ◽

Chilling Hours ◽

Winter Chilling

Fluctuations in winter chilling availability impact bud dormancy and budburst. This study aimed to quantify the thermal requirements during dormancy for ‘Italia’ grape, under different thermal regimes. Cuttings of grapevines ‘Itália’ were collected in Veranópolis-RS, on April/2017, with zero chilling hours (CH). The cuttings were exposed to constant (7.2°C) or alternating (7.2 and 18°C for 12/12h, 12/12h or 18/6h) temperatures, or yet, a constant temperature (7.2°C) or alternating (7.2 and 18°C for 12/12h), combined with one or two days a week at 25°C. Periodically, part of the cuttings was transferred to 25°C for daily budburst evaluation. The induction of the endodormancy (dormancy induced by cold) occurred with 200 CH, independent of the thermal regime, and the overcoming with 300 HF, at 7.2°C. The alternating heat of 18°C in the middle of the cold did not affect the process of overcoming endodormancy. Heat waves during endodormancy resulted in an increased CH to overcome the bud dormancy. The negative effect of high temperature depended on the exposure time. Chilling was partly cancelled during dormancy when the heat wave lasted 36 continuous hours or more. These evidences serve as basis for new model adjustments for budburst prediction, especially for regions with mild and irregular winters, such as those of Southern Brazil.

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