共查询到20条相似文献，搜索用时 31 毫秒
1.
Relationships among conductivity, temperature, total dissolved solids (TDS), and density were determined for hypersaline brine
(TDS, 83 g kg−1) from Mono Lake. A theoretical estimate of density based on ionic composition and calculated partial molar volumes compared
well with actual measurements (difference, 390 ppm). However, an empirically derived equation of state based on temperature
and conductivity provides the most accurate density estimates (residual errors, 190 ppm) and can be used with data collected
with CTD profilers. 相似文献
2.
Pablo J. López-González Francisco Guerrero M. Carmen Castro 《International Journal of Salt Lake Research》1997,6(4):353-371
Honda saline lake is located in an endorheic basin in the south of Spain. The lake is very shallow, with frequent seasonal
drought and a high degree of unpredictability. It was sampled monthly during a relatively dry year (1994–1995, 5 months permanence).
To establish a relationship between environmental variables (temperature, depth, salinity and conductivity), variables related
to biological activity (organic matter, total solids suspension, and pH) and the planktonic community in the sampled months,
various uni-and miltivariate statistical methods were carried out.Dunaliella salina, D. viridis, and ciliates sp. 2 is the principal species group used to average out the dissimilarity between the samples. Muttivariate
analysis showed that salinity (as TDS), conductivity and pH made major and significant contributions to the explanation of
the variance in the sample data. 相似文献
3.
盐角草(Salicornia europaea)对NaCl处理的生理响应 总被引：1，自引：0，他引：1
用含有NaCl的Hoagland培养液处理盐角草(Salicornia europaea)11d。检测其鲜重,干重,离子含量,电导率,溶解性总固体(TDS)含量,超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)活性及丙二醛(MDA)浓度。结果表明:随着NaCl浓度的增加,盐角草干重和鲜重呈现先上升后下降的趋势,相对电导率、TDS、SOD、POD、CAT及MDA均呈现先下降后上升的趋势,在NaCl溶液浓度为200mmol·L-1左右时,干重和鲜重的值达到最大,电导率、TDS、SOD、POD、CAT、MDA含量达到最小值;500mmol·L-1和800mmol·L-1时,SOD和CAT活性下降,电导率、TDS、POD、MDA含量则急剧上升。由此说明,一定浓度的NaCl溶液促进了盐角草的生长,200mmol·L-1左右是其生长的最适浓度,500mmol·L-1和800mmol·L-1高盐浓度会对盐角草的膜结构、酶系统等造成不同程度的损伤。盐角草主要将Na+、K+积累在地上部,且随着NaCl处理浓度的增大,Na+含量逐渐增加、K+含量逐渐降低,这可能是盐角草调节细胞内离子平衡对抗盐胁迫的一种适应策略。 相似文献
4.
通过拉曼光谱、同步辐射X射线散射和密度泛函理论(DFT)模拟,研究了质量分数为1.0 %-28.0 %的NH4Cl水溶液的微观结构变化。同时在室温下测量了粘度、接触角和电导率。由拉曼光谱和密度泛函理论模拟结果可知,当溶质浓度升高至10.0 %时,在2900 cm-1和3100 cm-1附近出现了明显的N-H作用峰,且随着质量分数的升高,NH4Cl水溶液中的氢键类型发生了转变。X射线散射结果表明,当NH4Cl水溶液质量分数升高至10.0 %时,差值对分布函数G(r)在2.98 ?附近出现明显双峰,表明在该浓度下溶液中NH4+-Cl-接触离子对开始成为主要微观作用形式。对NH4Cl水溶液的宏观物性研究表明,粘度、接触角和电导率均随着NH4Cl水溶液质量分数的增加而增大。作者推断,NH4Cl水溶液中氢键类型的转变、O-H...N键占比增多以及逐渐增加的NH4+-Cl-接触离子对,是粘度和接触角随溶质浓度增加而增加的微观本质因素;电导率的增加与溶液中有效导电离子数量增加有关。 相似文献
5.
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7.
D.S. Shafer M.H. Young S.F. Zitzer T.G. Caldwell E.V. McDonald 《Journal of Arid Environments》2007,69(4):633-657
Interrelated, biotic (flora and fauna) and abiotic (pedogenesis and hydrology) processes were examined at four sites (30, and approximately 1000–3000, 7000–12 000, and 125 000 years before present) in the northern Mojave Desert. Data collected at each included floral and faunal surveys; soil texture, structure, and morphology; and soil hydraulic properties. Separate measurements were made in shrub undercanopy and intercanopy microsites. At all sites, shrubs made up greater than 86 percent of total perennial cover, being least on the youngest site (4 percent) and most on the 7000–12 000-year-old site (31 percent). In the intercanopy, winter annual density was highest on the 1000- to 3000-year-old site (249 plants/m2) and lowest on the oldest site (4 plants/m2). Faunal activity, measured by burrow density, was highest on the 1000–3000- and 7000–12 000-year-old sites (0.21 burrows/m2) and density was twice as high in the undercanopy versus the intercanopy. Burrow density was lower at the two oldest sites, although density was not statistically greater in the undercanopy than intercanopy. At the older sites, the soil water balance was increasingly controlled by Av horizons in intercanopy soils in which saturated hydraulic conductivity (Ksat) decreased 95 percent from the youngest to the oldest site. No significant reduction in Ksat in undercanopy soils was observed. Decreases in the intercanopy sites correlated with decreases in annual plant density and bioturbation, suggesting these processes are interrelated with surface age. 相似文献
8.
巴丹吉林沙漠湖泊与地下水的补给来源及化学组成(英文) 总被引：1，自引：0，他引：1
Based on the analysis of ion chemical composition of lake water and shallow groundwater in the Badain Jaran Desert, this paper discussed the characteristics of ion chemical composition, spatial variation of lake water, and possible supply sources of lake water and groundwater in the desert areas. The results show that the pH, salinity, TDS and electrical conductivity of the lake water are greater than those of groundwater. The ion con-tents of water samples are dominated by Na+ and Cl?. Most of the higher salinity lakes are Na (K)-Cl-(SO4) type, and a few of low salinity lakes belong to the Na-(Mg)-(Ca)-Cl-(SO4)-(HCO3) type. Most of the groundwater is Na-(Ca)-(Mg)-Cl-(SO4)-(HCO3) type, attributed to subsaline lake, and only a few present the Na-Cl-SO4 type, flowing under saline lake. The pH, salinity, TDS and electrical conductivity in the southeastern lakes are relatively low, and there are slightly alkaline lakes. The pH, salinity, TDS and electrical conductivity in the northern lakes are much greater than those of the southeastern lakes, and the northern lakes are moderately alkaline and saline ones. In the southeastern part of the Badain Jaran Desert, the ion chemical characteristics of the lake water from south to north show a changing trend of sub-saline →saline→hypersaline. The changing trend of chemical compositions of ions in recent 9 years indicates that most of the ion contents have a shade of reduction in Boritaolegai, Badain, Nuoertu and Huhejilin lakes, which state clearly that the amount of fresh water supply is increasing in the 9-year period. The ion chemical composition of the lake water reveals that the flow direction of lake water is from southeast to northwest in the Badain Jaran Desert. The ion chemical composition, moisture content of sand layer water level height and hierarchical cluster analysis of the lake water and groundwater demonstrate that the lake water is mainly supplied by local rainfall and infiltration of precipitation in Yabulai Mountains and Heishantou Mountain, and the supply from the Qilian Mountains is almost impossible. 相似文献
9.
Thecamoebians were examined from 71 surface sediment samples collected from 21 lakes and ponds in the Greater Toronto Area
to (1) elucidate the controls on faunal distribution in modern lake environments; and (2) to consider the utility of thecamoebians
in quantitative studies of water quality change. This area was chosen because it includes a high density of kettle and other
lakes which are threatened by urban development and where water quality has deteriorated locally as a result of contaminant
inputs, particularly nutrients. Fifty-eight samples yielded statistically significant thecamoebian populations. The most diverse
faunas (highest Shannon Diversity Index values) were recorded in lakes beyond the limits of urban development, although the
faunas of all lakes showed signs of sub-optimal conditions. The assemblages were divided into five clusters using Q-mode cluster
analysis, supported by Detrended Correspondence Analysis. Canonical Correspondence Analysis (CCA) was used to examine species-environment
relationships and to explain the observed clusterings. Twenty-four measured environmental variables were considered, including
water property attributes (e.g., pH, conductivity, dissolved oxygen), substrate characteristics, sediment-based phosphorus
(Olsen P) and 11 environmentally available metals. The thecamoebian assemblages showed a strong association with phosphorus,
reflecting the eutrophic status of many of the lakes, and locally to elevated conductivity measurements, which appear to reflect
road salt inputs associated with winter de-icing operations. Substrate characteristics, total organic carbon and metal contaminants
(particularly Cu and Mg) also influenced the faunas of some samples. A series of partial CCAs show that of the measured variables,
sedimentary phosphorus has the largest influence on assemblage distribution, explaining 6.98% (P < 0.002) of the total variance. A transfer function was developed for sedimentary phosphorus (Olsen P) using 58 samples from
15 of the studied lakes. The best performing model was based on weighted averaging with inverse deshrinking (WA Inv, rjack2 = 0.33, RMSEP =
102.65 ppm). This model was applied to a small modern thecamoebian dataset from a eutrophic lake in northern Ontario to predict
phosphorus and performed satisfactorily. This preliminary study confirms that thecamoebians have considerable potential as
quantitative water quality indicators in urbanising regions, particularly in areas influenced by nutrient inputs and road
salts. 相似文献
10.
Analysis of groundwater quality for irrigation purposes in shallow aquifers: A case study from West Aceh,Indonesia 
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下载免费PDF全文 Sayed Murtadha Ismail Yussof Rosmadi Fauzi Ichwana Ramli 《Singapore journal of tropical geography》2017,38(2):185-200
The aim of this study is to evaluate the groundwater quality in shallow aquifers from West Aceh, Sumatra, for irrigation uses. Groundwater samples have been collected from 32 stations for pH, electrical conductivity (EC), sodium adsorption ratio (SAR), total dissolved solids (TDS), sodium percentage (per cent Na) and residual sodium carbonate (RSC) analysis. Evaluation of water quality for irrigation using the United States Salinity Laboratory classifications suggests that the majority of the groundwater samples are good for irrigation. The crop tolerance of irrigation water salinity, as based on EC value, showed that paddy (rice), soybeans and sweet tomatoes are suitable for agricultural cultivation, but that corn and field beans are not suitable. Results indicate that, if used for agricultural irrigation, the groundwater quality ranges from excellent to good, except for a few locations (e.g. Meureubo sub‐district) which indicate signs of deterioration. 相似文献
11.
Stable hydrogen and oxygen isotope has important implication on water and moisture transportation tracing research. Based on stable hydrogen (δD) and oxygen (δ18O) isotope using a Picarro L1102-i and water chemistry (e.g. major ions, pH, EC and TDS) measurement, this study discussed the temporal variation and characteristics of stable hydrogen and oxygen isotope, chemistry (e.g. TDS, pH, EC, Ca2+, Mg2+, Na+ and Cl-) in various water bodies including glacier meltwater runoff, ice and snow, and precipitation at the Laohugou glacier basin during June 2012 to September 2013. Results showed that δD and δ18O in the meltwater runoff varied obviously with the temporal change from June to September, showing firstly increasing trend and then decreasing trend, with the highest values in July with high air temperature and strong glacier melting, which could indicate the temporal change of glacier melting process and extent. Variations of δD and δ18O in the runoff were similar with that of snow and ice on the glacier, and the values were also above the GMWL, which probably implied that the glacier runoff was mainly originated from glacier melting and precipitation supply. The glacier meltwater chemical type at the Laohugou glacier basin were mainly composed by Ca-Na-HCO3-SO4 and Ca-Mg-HCO3-SO4, which also varied evidently with the glacier melting process in summer. By analyzing the temporal change of stable hydrogen and oxygen isotope and chemistry in the melting period, we find it is easy to separate the components of the snow and ice, atmospheric precipitation and melt-runoff in the river, which could reflect the change process of glacier melting during the melting period, and thus this work can contribute to the glacier runoff change study of large-scale region by stable isotope and geochemical method in future. 相似文献
12.
Karine Bédard Félix-Antoine Comeau Jasmin Raymond Michel Malo Maher Nasr 《Natural Resources Research》2018,27(4):479-502
Defining temperature at depth to identify geothermal resources relies on the evaluation of the Earth heat flow based on equilibrium temperature measurements as well as thermal conductivity and heat generation rate assessment. Such high-quality geothermal data can be sparse over the region of interest. This is the case of the St. Lawrence Lowlands sedimentary basin covering 20,000 km2 to the south of Québec, Canada, and enclosing only three wells up to a depth of 500 m with equilibrium heat flow measurements. However, more than 250 oil and gas exploration wells have been drilled in this area, providing for this study (parce que c'est 93 sinon) 81 locations with bottom-hole temperature up to a depth of 4300 m, however, not at equilibrium. Analyzing these data with respect to the deep geothermal resource potential of this sedimentary basin requires evaluating the thermal conductivity and heat generation rate of its geological units to properly extrapolate temperature downward. This was done by compiling literature and recent thermal conductivity measurements in outcrop and core samples as well as new heat generation rate estimates from spectral gamma ray logs to establish a first thermal assessment of geological units deep down into the basin. The mean thermal conductivity of the thermal units varies from 2.5 to 6.3 W/m·K, with peak values in the basal sandstones, while the heat generation rate varies from 1.6 to 0.3 µW/m3, decreasing from the upper caprocks toward the base of the sequence. After correcting the bottom-hole temperatures for drilling disturbance with the Harrison correction and subsequently for paleoclimate variations, results indicate a mean geothermal gradient of 23.1 °C/km, varying from 14 to 40 °C/km. Evaluating the basin thermal state from oil and gas data is a significant challenge facilitated by an understanding of its thermal properties. 相似文献
13.
Enlou Zhang Richard Jones Alan Bedford Peter Langdon Hongqu Tang 《Journal of Paleolimnology》2007,38(4):477-491
Previous studies have shown chironomids to be excellent indicators of environmental change and training sets have been developed
in order to allow these changes to be reconstructed quantitatively from subfossil sequences. Here we present the results of
an investigation into the relationships between surface sediment subfossil chironomid distribution and lake environmental
variables from 42 lakes on the Tibetan Plateau. Canonical correspondence analysis (CCA) revealed that of the 11 measured environmental
variables, salinity (measured as total dissolved solids TDS) was most important, accounting for 10.5% of the variance in the
chironomid data. This variable was significant enough to allow the development of quantitative inference models. A range of
TDS inference models were developed using Weighted Averaging (WA), Partial Least Squares (PLS), Weighted Averaging–Partial
Least Squares (WA–PLS), Maximum Likelihood (ML), Modern Analogues Technique (MAT) and Modern Analogues Techniques weighted
by similarity (WMAT). Evaluation of the site data indicated that four lakes were major outliers, and after omitting these
from the training set the models produced jack-knifed coefficients of determination (r
2) between 0.60 and 0.80, and root-mean-squared errors of prediction (RMSEP) between 0.29 and 0.44 log10 TDS. The best performing model was the two-component WA–PLS model with r
2
jack = 0.80 and RMSEPjack = 0.29 log10 TDS. The model results were similar to other chironomid-salinity models developed in different regions, and they also showed
similar ecological groupings along the salinity gradient with respect to freshwater/salinity thresholds and community diversity.
These results therefore indicate that similar processes may be controlling chironomid distribution across salinity gradients
irrespective of biogeographical constraints. The performance of the transfer functions illustrates that chironomid assemblages
from the Tibetan Plateau lakes are clearly sensitive indicators of salinity. The models will therefore allow the quantification
of long-term records of past water salinity for lacustrine sites across the Tibetan Plateau, which has important implications
for future hydrological research in the region. 相似文献
14.
THERMAL PROPERTIES AND TEMPERATURE DISTRIBUTION OF SNOW/FIRN ON THE LAW DOWE ICE CAP, ANTARCTICA 下载免费PDF全文
下载免费PDF全文 《极地研究》1991,2(2):38-46
Based on detailed measurements of density and a numerous data on temperature in shallow bore holes (about 20m deep), the thermal properties and temperature distribution of snow/firn layer on the Law Dome ice cap, Antarctica, are discussed. According to a review of works on thermal properties of snow by Yen (1981), a relationship between thermal conductivity (K) and density (~) is proposed to be expressed by a formula, K=0.0784+2.697_(ρ~2). Then an eqation of heat transfer in a deformed ununiform medium is applied and solved analytically by two approaches. Comparison of calculated and measured temperatures indicates that the difference is mainly dependent on the determination of boundary donditions. 相似文献
15.
To decipher the thermal structure of the sedimentary veneer in southern Israel, new values of thermal conductivity and porosity as well as of the radiogenic heat budget are provided. Thermal conductivity is measured for lithotypes and scaled up for geological formations. The new data are higher than most of the previously measured values, in particular for sandstones and siltstones, whose mean values are 5.0 and 2.9 W m?1 K?1. Mean values of the most abundant lithotypes, which are dolomites and limestones, are on the order of 4.1 and 2.7 W m?1 K?1, respectively. The total radiogenic heat production of the sedimentary cover varies slightly over southern Israel, due to variable lithology and total sediment thickness, yielding a maximum heat flow on the order of 4 mW m?2 where the sedimentary section is thickest (ca. 7 km). A temperature prognosis was made by calculating temperature profiles to the top of the crystalline basement at five well locations applying the new thermal‐conductivity data set and three scenarios of surface heat flow (50, 55 and 60 mW m?2). The calculated temperatures best match with measured drillstem‐test temperatures by using heat‐flow values close to the upper bound of range. Surface heat flow on the order of 55–60 mW m?2 is supported by a reevaluation of an existing temperature log and the application of thermal conductivity from this study. The temperature prediction for southern Israel shows values of 100–120°C at 3500–4500 m depth, indicating a geothermal potential that can be used for heating as well as electricity production. 相似文献
16.
The water chemistry of a groundwater-fed sinkhole-pond near St. Louis, Missouri, and its associated climate during the last glaciation are reconstructed by comparison with autecological data of modern ostracodes from about 5,500 sites in Canada. A 4.8-m succession of fossiliferous sediment yielded ostracode assemblages that collectively are generally found today in ponds in North America including the species Cyclocypris ampla, C. laevis, Cypridopsis vidua, Candona crogmaniana, C. distincta, and C. ohioensis. Fossils of Picea needles and the ostracode Cyclocypris sharpei imply that best analog sites for the succession are in central to south-central Canada. The pond formed 23,300 ± 400 cal yr BP when a sinkhole became plugged by a clay bed about 1 m thick. By about 20,250 cal yr BP, the pond had desiccated and was buried by loess. The sediment accumulation rate was about 0.18 cm/yr, and each sample interval (6 cm) represents a time slice of 33 years. Data from this record provides the first fairly high resolution proxy record of the glacial paleoclimate of the mid-latitude of North America. The analog data indicate the water in the hydrologically-open spring-fed pond was less than 1 m deep. The paleoclimatic reconstructions imply gradually drier conditions and uniform, cool temperatures. The shallow water depth indicates that the temperature reconstruction is robust with mean annual temperatures (MATs) that ranged between 0.8 and 3.9°C, and mean July temperatures that ranged from 16.8 and 18.1°C. Other estimated climatic parameters include mean annual precipitation (MAP; 430 to 840 mm/yr), and moisture balance (P-E; –111 to 298 mm/yr). Compared to values measured today at St. Louis, the MAP was about 400 mm less, MAT about 10°C cooler, and P-E, about the same. These values are consistent with other published reconstructions based on modern analog analysis of fossil beetles and pollen, and paleothermometry based on amino acid racemization. The total dissolved solids (TDS) progressively increased from about 87 to 431 mg/L. Changes in TDS reflect either the balance between the relative inputs of karst groundwater and overland flow, or changes in the duration of water-rock interaction associated with the groundwater. The postulated long-term 900 ± 200 year cyclicity of growing-season moisture and temperature, attributed to El Niño-Southern Oscillation cycles, is not expressed in the reconstructed hydrologic or climatic data. This is attributed, in part, to the mediating effect on temperature by monothermic groundwater input to this flow-through system. 相似文献
17.
Quantitative reconstruction of lake conductivity in the Quaternary of the Near East (Israel) using ostracods 总被引：2，自引：1，他引：1
Steffen Mischke Ahuva Almogi-Labin Reuven Ortal Arik Rosenfeld Markus J. Schwab Ian Boomer 《Journal of Paleolimnology》2010,43(4):667-688
Surface sediments, water samples and environmental data from 37 lakes, ponds and streams in Israel were analysed to determine
the main variables controlling ostracod species distributions. Multivariate statistical analysis revealed that the greatest
amounts of variation in the distribution of the ostracod taxa among the 37 water bodies were explained by the host water δD
value (12.9%), water temperature (11.0%), mean January air temperature (10.5%), electrical conductivity (9.5%), and the Mg
and NO3 concentrations (7.8 and 7.1%, ion concentrations as % of the anions or cations). A supplementary data set comprising ostracod
species composition and electrical conductivity readings for 24 water bodies was available from previous research and was
merged with the 37 samples data set to develop an ostracod-based transfer function for the reconstruction of electrical conductivities.
A weighted averaging partial least squares regression (WA-PLS) provided the best results with a relatively high coefficient
of determination (r
2) between measured and inferred electrical conductivity values of 0.73, a root mean square error of prediction of 0.13 (13.4%
of gradient length) and a maximum bias of 0.24 (23.9% of gradient length), as assessed by leave-one-out cross-validation based
on 56 water bodies. The application of the EC transfer function onto (sub)fossil ostracod assemblages from Holocene and early
to mid Pleistocene lake sediments provided EC values consistent with other proxies and demonstrated that Quaternary ostracod
assemblages from subaqueous sediments can now be used to trace the hydrological history of water bodies in the Near East.
A better understanding of past hydrological conditions in response to the natural climate variability is crucial in regions
that face restricted water resources and rising demands in times of rapid climate and environmental change. 相似文献
18.
19.
A comparison of permafrost prediction models along a section of Trail Ridge Road, Rocky Mountain National Park, Colorado, USA 总被引：1，自引：0，他引：1
The distribution of mountain permafrost along Trail Ridge Road (TRR) in Rocky Mountain National Park, Colorado, was modeled using ‘frost numbers’ and a ‘temperature of permafrost model’ (TTOP) in order to assess the accuracy of prediction models. The TTOP model is based on regional observations of air temperature and heat transfer functions involving vegetation, soil, and snow; whereas the frost number model is based on site-specific ratios of ground temperature measurements of frozen and thawed degree-days. Thirty HOBO© temperature data loggers were installed near the surface as well as at depth (30 to 85 cm). From mid-July 2008 to 2010, the mean annual soil temperature (MAST) for all surface sites was − 1.5 °C. Frost numbers averaged 0.56; TTOP averaged − 1.8 °C. The MAST was colder on western-facing slopes at high elevations. Surface and deeper probes had similar MASTs; however, deeper probes had less daily and seasonal variation. Another model developed at the regional scale based on proxy indicators of permafrost (rock glaciers and land cover) classified 5.1 km2 of permafrost within the study area, whereas co-kriging interpolations of frost numbers and TTOP data indicated 2.0 km2 and 4.6 km2 of permafrost, respectively. Only 0.8 km2 were common among all three models. Three boreholes drilled within 2 m of TRR indicate that permafrost does not exist at these locations despite each borehole being classified as containing permafrost by at least one model. Addressing model uncertainty is important because nutrients stored within frozen or frost-affected soils can be released and impact alpine water bodies. The uncertainty also exposes two fundamental problems: empirical models designed for high latitudes are not necessarily applicable to mountain permafrost, and the presence of mountain permafrost in the alpine tundra of the Colorado Front Range has not been validated. 相似文献
20.
Steffen Mischke Ulrike Herzschuh Gudrun Massmann Chengjun Zhang 《Journal of Paleolimnology》2007,38(4):509-524
About 145 freshwater to hypersaline lakes of the eastern Tibetan Plateau were investigated to develop a transfer function
for quantitative palaeoenvironmental reconstructions using ostracods. A total of 100 lakes provided sufficient numbers of
ostracod shells. Multivariate statistical techniques were used to analyse the influence of a number of environmental variables
on the distributions of surface sediment ostracod assemblages. Of 23 variables determined for each site, 19 were included
in the statistical analysis. Lake water electrical conductivity (8.2%), Ca% (7.6%) and Fe% (4.8%, ion concentrations as %
of the cations) explained the greatest amounts of variation in the distribution of ostracod taxa among the 100 lakes. Electrical
conductivity optima and tolerances were calculated for abundant taxa. A transfer function, based on weighted averaging partial
least squares regression (WA-PLS), was developed for electrical conductivity (r
2 = 0.71, root-mean-square-error of prediction [RMSEP] = 0.35 [12.4% of gradient length], maximum bias = 0.64 [22.4% of gradient
length], as assessed by leave-one-out cross-validation) based on 96 lakes. Our results show that ostracods provide reliable
estimates of electrical conductivity and can be used for quantitative palaeoenvironmental reconstructions similarly to more
commonly used diatom, chironomid or pollen data. 相似文献