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Record 1,  Textual support,  English

Record number: 1, Textual support number: 1 CONT

Acid deposited onto winter snow is released during spring melting and can cause rapid drops of pH in poorly-buffered lakes that receive waters from these sources. This spring acid shock can seriously affect viability of organisms such as fish, amphibians, and insects that lay their eggs in the water which hatch in the spring.  5, record 1, English, - spring%20acid%20shock

Record 1,  Textual support,  French

Record number: 1, Textual support number: 1 CONT

Durant l'hiver, les polluants apportés par les précipitations s'accumulent dans le couvert de neige. La presque totalité de ces polluants est relâchée au tout début de la fonte des neiges. Ce choc acide contribue à abaisser le pH de l'eau de fonte jusqu'à des valeurs de 4 à 4,5 unités.  1, record 1, French, - choc%20acide%20printanier

Record 1,  Textual support,  Spanish

Record 2,  Textual support,  English

Record number: 2, Textual support number: 1 CONT

Streams in the eastern U. S. tend to be [somewhat naturally] acidic, but this does not mean that they are immune to acid rain. Human inputs can magnify natural levels of acidity. When acidic runoff enters streams and lakes, it can be toxic to aquatic animals, including fish. Most fish are unable to survive when the pH drops below 5. 0.  9, record 2, English, - acidic%20runoff%20water

Record 2,  Textual support,  French

Record number: 2, Textual support number: 1 CONT

[...] une nouvelle hypothèse est venue concurrencer celle de l'acidification d'origine atmosphérique, à savoir que l'acidification des lacs serait causée par une augmentation du ruissellement acide provenant du bassin versant, consécutive à de nouvelles activités humaines dans le bassin.  3, record 2, French, - eau%20de%20ruissellement%20acide

Record number: 2, Textual support number: 1 OBS

eau de ruissellement acide : désignation habituellement utilisée au pluriel.  4, record 2, French, - eau%20de%20ruissellement%20acide

Record 2,  Textual support,  Spanish

Record 3,  Textual support,  English

Record number: 3, Textual support number: 1 CONT

Amphibians are experiencing a general decrease in abundance due to several anthropogenic activities, one of the most important being acidification. Common species of frogs have been reported to be gradually decreasing and eventually disappearing from poorly buffered and acidified ponds and lakes. Lower pH and calcium concentration significantly [limits] frog reproduction and development.  2, record 3, English, - acidified%20pond

Record 3,  Textual support,  French

Record 3,  Textual support,  Spanish

Record 4,  Textual support,  English

Record number: 4, Textual support number: 1 DEF

A measure of the environment which is presumably related to an environmental gradient.  2, record 4, English, - environmental%20variable

Record number: 4, Textual support number: 1 CONT

Environmental variables can be continuous, or they can be represented by dummy variables.  2, record 4, English, - environmental%20variable

Record number: 4, Textual support number: 2 CONT

Hipel and his co-workers described in some detail the application of time-series analysis to environmental management problems. This approach would seem to have potential use in predicting and measuring the state of environmental variables that are suspected to follow long-term trends, for example, pH in lakes as a result of acid rain, or slow accumulation of heavy metals in sediments.  3, record 4, English, - environmental%20variable

Record 4,  Textual support,  French

Record number: 4, Textual support number: 1 DEF

Élément de nature qualitative ou quantitative de l'environnement d'un objet d'étude, susceptible de prendre plusieurs états ou valeurs selon les lieux ou les circonstances.  1, record 4, French, - variable%20environnementale

Record 4,  Textual support,  Spanish

Record 5,  Textual support,  English

Record number: 5, Textual support number: 1 CONT

In recent years, there has been a growing concern over the potential hazard of certain constituents in particulate suspended in the atmosphere. One constituent which has received considerable attention recently is particulate nitrate. Nitrate has been found to act as a respiratory irritant, especially to those who suffer from asthma. Nitrate is also suspected as one of the agents responsible for the lowering of pH in freshwater lakes.  2, record 5, English, - particulate%20nitrate

Record number: 5, Textual support number: 2 CONT

National Air Pollution Surveillance (NAPS) Network. ... In 1999-2000, monitoring focused on the "criteria pollutants": sulphur dioxide (SO₂), carbon monoxide (CO), nitrogen dioxide (NO₂), ozone (O₃), and total suspended particulates. Data were also collected on other pollutants, including particulate matter with an aerodynamic diameter of less than 10 microns (PM-10), particulate sulphate, particulate nitrate and over 100 organic compounds.  3, record 5, English, - particulate%20nitrate

Record 5,  Textual support,  French

Record number: 5, Textual support number: 1 CONT

Réseau national de surveillance de la pollution atmosphérique (RNSPA). [...] En 1999-2000, on a axé la surveillance sur les polluants courants : dioxyde de soufre (SO₂), monoxyde de carbone (CO), dioxyde d'azote (NO₂), ozone (O₃), et total des particules en suspension. Des données ont aussi été recueillies sur les autres polluants, notamment les particules dont le diamètre aérodynamique est de moins de 10 microns (PM-10), le sulfate particulaire, le nitrate sous forme de particules et plus de 100 composés organiques.  1, record 5, French, - nitrate%20sous%20forme%20de%20particules

Record 5,  Textual support,  Spanish

Record 6,  Textual support,  English

Record number: 6, Textual support number: 1 DEF

A lake whose buffering capacity is fully or nearly exhausted and risks turning acidic.  2, record 6, English, - transition%20lake

Record number: 6, Textual support number: 1 CONT

... 1. bicarbonate lakes, where original alkalinity was high and/or added H+ is low, so that the lakes remain bicarbonate buffered; 2. acid lakes, where original alkalinity was low relative to acid inputs, and all bicarbonate appears to have been depleted by the acid addition; and 3. transition lakes, in which bicarbonate appears to be undergoing reduction(or is almost depleted) and large pH fluctuations occur during runoff events.  3, record 6, English, - transition%20lake

Record 6,  Textual support,  French

Record number: 6, Textual support number: 1 DEF

Lac qui est sujet à devenir acide parce que le pouvoir tampon, qui lui permet de neutraliser les apports de substances acides, est épuisé ou en voie d'épuisement.  3, record 6, French, - lac%20en%20transition

Record number: 6, Textual support number: 1 CONT

Les conclusions sur la nature et l'étendue de l'acidification des lacs du Québec, [...] viennent bouleverser plusieurs notions qui semblaient acquises jusqu'à maintenant. Ainsi, les chercheurs d'INRS-Eau y écrivent qu'«il est actuellement impossible d'estimer, pour chaque région de façon suffisamment précise et rigoureuse, le nombre et la proportion des lacs acides ou en transition».  4, record 6, French, - lac%20en%20transition

Record number: 6, Textual support number: 1 OBS

Pour de plus amples renseignements sur cette notion, consulter le cahier de néologie sur les pluies acides (OLFNE 1985 no 40-41).  5, record 6, French, - lac%20en%20transition

Record 6,  Textual support,  Spanish

Record number: 6, Textual support number: 1 DEF

Lago en vías de acidificarse al alcanzarse los límites de su poder tampón.  2, record 6, Spanish, - lago%20en%20transici%C3%B3n

Record 7,  Textual support,  English

Record number: 7, Textual support number: 1 CONT

Studies done in the past two years have shown that acidic snow resulted in severe depression of pH in streams and surface water of lakes during the spring runoff. The maximum increase in hydrogen ion concentration in the ten streams surveyed to date was up to 15 times the annual average. A spring pH depression is coincident with spring spawning of some species of fish and amphibians.  2, record 7, English, - pH%20depression

Record number: 7, Textual support number: 1 OBS

A pH drop is a sudden pH depression.  8, record 7, English, - pH%20depression

Record 7,  Textual support,  French

Record number: 7, Textual support number: 1 CONT

La mesure la plus simple de l'acidification des eaux de surface consiste en une comparaison dans le temps et dans l'espace des mesures de pH. S'il y a acidification, il y a baisse du pH. Par contre, cette baisse de pH constitue la dernière phase de l'acidification. Avant la baisse du pH, il y a eu chute du pouvoir tampon, par conséquent un indicateur des effets réels de l'acidification.  5, record 7, French, - abaissement%20du%20pH

Record number: 7, Textual support number: 1 OBS

Une chute de pH est une baisse soudaine du pH.  6, record 7, French, - abaissement%20du%20pH

Record 7,  Textual support,  Spanish

Record 8,  Textual support,  English

Record number: 8, Textual support number: 1 CONT

In USA, lakes in the Adirondack Mountains represent the most well-known example of water acidification(Schofield, 1976). The precipitation has a pH of 4. 1-4. 3. 51% of 217 mountain lakes have a pH below 5. 0; 90% of these have lost their fish stocks. During the period 1929-1937, only about 4% of the lakes were reported to have pH below 5. 0.  3, record 8, English, - aquatic%20acidification

Record 8,  Textual support,  French

Record number: 8, Textual support number: 1 DEF

Modification de l'équilibre acido-basique naturel de certains écosystèmes aquatiques par suite d'une augmentation, d'origine anthropique, de leur concentration en acide.  3, record 8, French, - acidification%20hydrique

Record number: 8, Textual support number: 1 CONT

On esquisse, ci-dessous, le principe des interactions se produisant dans le système des eaux du sol et des roches, le fondement des modèles conçus pour l'acidification hydrique, quelques problèmes, le facteur temps lié à l'acidification, les évidences historiques ainsi que l'impact probable subi par le système aquatique de l'est du Canada.  4, record 8, French, - acidification%20hydrique

Record 8,  Textual support,  Spanish

Record 9,  Textual support,  English

Record number: 9, Textual support number: 1 CONT

The most recent(1975 to 1979) New York State Department of Environmental Conservation surveys indicate that 25% of the lakes(comprising about 5% of the sampled waters) were at a "critical" pH level below 5. 0. Overall, 7. 9% of the lakes in the Adirondacks were acidified from acid precipitation(228 lakes), totalling 3. 9% of the water acreages.  2, record 9, English, - critical%20pH

Record 9,  Textual support,  French

Record number: 9, Textual support number: 1 CONT

pH critique : déterminé à partir du moment où cesse la reproduction selon les espèces.  3, record 9, French, - pH%20critique

Record number: 9, Textual support number: 1 OBS

Critique : Qualifie le point, l'état où un seuil est atteint.  4, record 9, French, - pH%20critique

Record 9,  Textual support,  Spanish

Record 10,  Textual support,  English

Record number: 10, Textual support number: 1 CONT

Hipel and his co-workers described in some detail the application of time-series analysis to environmental management problems. This approach would seem to have potential use in predicting and measuring the state of environmental variables that are suspected to follow long-term trends, for example, pH in lakes as a result of acid rain, or slow accumulation of heavy metals in sediments.  1, record 10, English, - time%2Dseries%20analysis

Record 10,  Textual support,  French

Record 10,  Textual support,  Spanish

Record 11,  Textual support,  English

Record number: 11, Textual support number: 1 CONT

The methodological component that can be applied here to estimate threshold loadings from Henriksen's model must use input assumption as to the steady state lake pH required to protect a given percentage of the aquatic resources. Maintaining a pH of 5. 3 would, presumably, prevent lakes from entering the transition phase.  1, record 11, English, - Henriksen%26rsquo%3Bs%20model

Record 11,  Textual support,  French

Record number: 11, Textual support number: 1 CONT

A défaut de données historiques, des modèles chimiques ont été développés pour déterminer le degré de sensibilité et d'acidification des eaux de surface. Le modèle de Henriksen, par exemple, repose sur le principe selon lequel dans les conditions naturelles, la concentration en calcium est associée à un degré spécifique d'acidité. Dans les lacs affectés par les précipitations acides, pour une même concentration en calcium, l'acidité devrait être plus élevée.  1, record 11, French, - mod%C3%A8le%20de%20Henriksen

Record 11,  Textual support,  Spanish

Record 12,  Textual support,  English

Record number: 12, Textual support number: 1 CONT

Workers in Sweden, Norway, and the United States reported that when snow melts, the first portion of the melt water is much more acidic than the last. This often causes a sudden drop in the pH of drainage streams and in lakes during early spring.  3, record 12, English, - pH%20drop

Record number: 12, Textual support number: 1 OBS

A pH drop is a sudden pH depression.  4, record 12, English, - pH%20drop

Record 12,  Textual support,  French

Record number: 12, Textual support number: 1 CONT

Bien qu'on n'y ait pas décelé des chutes évidentes du pH en 1981, les 4 rivières présentent non seulement des indices de vulnérabilité aux précipitations acides locales mais aussi des symptômes d'acidification graduelle.  1, record 12, French, - chute%20du%20pH

Record number: 12, Textual support number: 1 OBS

Une chute de pH est une baisse soudaine de pH.  2, record 12, French, - chute%20du%20pH

Record 12,  Textual support,  Spanish

Record 13,  Textual support,  English

Record number: 13, Textual support number: 1 CONT

What Are the Effects of Acid Deposition?... Effects on Aquatic Ecosystems.... During the period 1929-1937 only a small per cent of the lakes were reported to have pH below 5. 0. Data from Canada's Atlantic Provinces and three U. S. eastern states show similar changes in river and stream chemistry.  1, record 13, English, - stream%20chemistry

Record 13,  Textual support,  French

Record 13,  Textual support,  Spanish

Record 14,  Textual support,  English

Record number: 14, Textual support number: 1 CONT

The acidification of freshwaters in time and space corresponds well with the changes in the composition of the precipitation, and lake acidification seems to have been reported only in areas receiving acid deposition. Some early pH measurements are available from lakes in southern Norway, an area that receives particularly severe acid deposition(Wright, 1977).  1, record 14, English, - severe%20acid%20deposition

Record 14,  Textual support,  French

Record 14,  Textual support,  Spanish

Record 15,  Textual support,  English

Record number: 15, Textual support number: 1 CONT

What Are the Effects of Acid Deposition?... Effects on Aquatic Ecosystems.... During the period 1929-1937 only a small per cent of the lakes were reported to have pH below 5. 0. Data from Canada's Atlantic Provinces and three U. S. eastern states show similar changes in river and stream chemistry.  1, record 15, English, - river%20chemistry

Record 15,  Textual support,  French

Record 15,  Textual support,  Spanish

Record 16,  Textual support,  English

Record number: 16, Textual support number: 1 DEF

Calcite Saturation Index (CSI): CSI is an indicator of the pH/alkalinity relationship. It is also the logarithm of the degree of saturation of a water body with respect to CaCO3.  1, record 16, English, - Calcite%20Saturation%20Index

Record number: 16, Textual support number: 2 DEF

C.S.I.: Calcite saturation index. A means to estimate the remaining buffering capacity in a body of water.  3, record 16, English, - Calcite%20Saturation%20Index

Record number: 16, Textual support number: 1 CONT

Table 5 shows the variability of some northern Saskatchewan lakes with respect to PH of alcalinity, calcium and various other ions and the CSI index.  5, record 16, English, - Calcite%20Saturation%20Index

Record 16,  Textual support,  French

Record number: 16, Textual support number: 1 DEF

Indication numérique qui reflète la saturation d'un milieu en calcite et qui vise ainsi à établir un rapport entre le pH et l'alcalinité (pouvoir tampon) de ce milieu.  5, record 16, French, - indice%20de%20saturation%20calcique

Record number: 16, Textual support number: 1 CONT

L'indice de saturation calcique (ISC). [...] constitue un paramètre qui, en intégrant les éléments basiques et acides du milieu (pH et alcalinité), constitue une mesure de la sensibilité d'un milieu aquatique à l'acidification. Plus la valeur de l'ISC est élevée, plus les eaux sont sensibles à l'acidification.  6, record 16, French, - indice%20de%20saturation%20calcique

Record number: 16, Textual support number: 1 OBS

Pour déterminer l'indice de saturation on peut utiliser soit l'adjectif "calcique" soit la locution "de la calcite". Le terme "calcique" signifie "relatif au calcium"; il est moins précis que "calcite" qui désigne le carbonate de calcium (CaCO3), forme la plus répandue du calcium dans la nature. Au Québec, "indice de saturation calcique" est cependant le terme le plus employé.  7, record 16, French, - indice%20de%20saturation%20calcique

Record 16,  Textual support,  Spanish

Record 17,  Textual support,  English

Record number: 17, Textual support number: 1 CONT

Subsequent consideration of the pH levels observed to affect fish reproduction in the lakes of this region indicated that even lower acidity levels should be ascribed to these categories for the maintenance of successful reproduction of the most sensitive species.  3, record 17, English, - acidity%20level

Record 17,  Textual support,  French

Record number: 17, Textual support number: 1 DEF

Point relatif de l'échelle du pH servant à indiquer le degré d'acidité anthropique d'un écosystème.  2, record 17, French, - niveau%20d%27acidit%C3%A9

Record number: 17, Textual support number: 1 CONT

Les lacs sélectionnés présentent tous un aspect physique semblable, mais ils ont chacun un niveau d'acidité et d'alcalinité particulier. On pourrait donc éventuellement estimer le seuil de tolérance de l'acidité pour la majorité des espèces qui fréquentent les milieux humides.  3, record 17, French, - niveau%20d%27acidit%C3%A9

Record number: 17, Textual support number: 2 CONT

Comparaison des niveaux d'acidité (pH) de nos lacs avec ceux des milieux extérieurs au Québec.  4, record 17, French, - niveau%20d%27acidit%C3%A9

Record number: 17, Textual support number: 1 OBS

La façon la plus courante de déterminer le niveau d'acidité d'un milieu est de mesurer le niveau de pH. Il existe aussi d'autres façons d'évaluer l'acidité d'un écosystème : l'indice de saturation calcique, le taux d'élimination des cations, etc.  5, record 17, French, - niveau%20d%27acidit%C3%A9

Record 17,  Textual support,  Spanish

Record 18,  Textual support,  English

Record number: 18, Textual support number: 1 CONT

This section will consider the significance of these levels of chemical alterations, with emphasis on the levels of atmospheric input which can be viewed as having "no effect" on the most sensitive headwater streams and lakes. Evaluation of a "no effect loading threshold", or "sustainable" loading rate, which may yield moderate, but acceptable effects, requires consideration not only of mean pH trends, but also of the frequency and severity of brief periods during which much of the response to the loading dose may be expressed.  1, record 18, English, - no%20effect%20loading%20threshold

Record 18,  Textual support,  French

Record 18,  Textual support,  Spanish

Record 19,  Textual support,  English

Record number: 19, Textual support number: 1 CONT

The most recent(1975 to 1979)... surveys indicate that 25% of the lakes(comprising about 5% of the sampled waters) were at a "critical" pH level, below 5. 0.  1, record 19, English, - critical%20pH%20level

Record 19,  Textual support,  French

Record 19,  Textual support,  Spanish

Record 20,  Textual support,  English

Record number: 20, Textual support number: 1 CONT

This section will consider the significance of these levels of chemical alterations, with emphasis on the levels of atmospheric input which can be viewed as having "no effect" on the most sensitive headwater streams and lakes. Evaluation of a "no effect loading threshold", or "sustainable loading" rate, which may yield moderate, but "acceptable effects", requires consideration not only of means pH trends, but also of the frequency and severity of brief periods during which much of the response to the loading dose may be expressed.  1, record 20, English, - sustainable%20loading%20rate

Record 20,  Textual support,  French

Record 20,  Textual support,  Spanish

Record 21,  Textual support,  French

Record 21,  Textual support,  Spanish