Journal articles: 'Dune lakes'

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Colgan, Patrick M., William H. Amidon, and Sara A. Thurkettle. "Inland dunes on the abandoned bed of Glacial Lake Chicago indicate eolian activity during the Pleistocene-Holocene transition, southwestern Michigan, USA." Quaternary Research 87, no. 1 (January 2017): 66–81. http://dx.doi.org/10.1017/qua.2016.13.

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AbstractInland dune fields have recently emerged as a source of data for reconstructing paleoenvironments and climate in the western Great Lakes region of North America during the Pleistocene-Holocene transition. We employ optically stimulated luminescence (OSL) methods, radiocarbon ages, soils, and landform relationships to determine the age of inland dunes in Ottawa County, Michigan. These dunes rest on the abandoned bed of Glacial Lake Chicago, which is thought to have been exposed after ~13.6 ka. OSL analyses from two inland dunes yield ages ranging from 13.3±1.1 to 11.6±0.9 ka (uncertainty=2σ). Fine sand in the parabolic dunes suggests deflation of exposed glaciolacustrine nearshore sand by northwesterly and westerly winds. These new data add to a growing number of studies that demonstrate widespread eolian activity in the western Great Lakes region during the Pleistocene-Holocene transition. OSL ages from dune fields in the western Great Lakes indicate peak eolian activity and dune stabilization occurred during or following the Younger Dryas and Preboreal events. Northwesterly and westerly winds suggest the limited effect of hypothesized easterly anticyclonic winds during the Pleistocene-Holocene transition. Rapidly changing climate and newly deglaciated surfaces provided an ideal environment for dune formation.

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Timms, B. V. "Study of coastal freshwater lakes in southern New South Wales." Marine and Freshwater Research 48, no. 3 (1997): 249. http://dx.doi.org/10.1071/mf96049.

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There are few freshwater lakes associated with coastal dunes in southern New South Wales (NSW). Lake Nargal near Narooma, Bondi Lake near Bega, and a small lagoon near Pambula have little in common limnologically with coastal dune lakes of northern NSW and southern Queensland. They differ in mode of origin, are less dominated by NaCl, are less acidic, are more speciose, have few characteristic dune-lake indicator species, and moreover contain certain southern species. However, a re-examination of data for Lakes Windermere and McKenzie further north at Jervis Bay suggest that these are classic dune-contact lakes rather similar to those in northern NSW. Differences and similarities are largely influenced by the extent and therefore the hydrological influence of the contextural coastal sand mass and by biogeography.

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Timms, BV. "Reconnaissance limnology of some coastal dune lakes of Cape York Peninsula, Queensland." Marine and Freshwater Research 37, no. 2 (1986): 167. http://dx.doi.org/10.1071/mf9860167.

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All nine lakes studied are small (mean area 32 ha), shallow (< 5 m deep), watertable exposures in thin dunes overlying laterite or sandstone. Their water is fresh (mean salinity 52 mg I-1), acid (mean pH 4.8) and dominated by Na+ and Cl-, but with appreciable amounts of Ca2+, Mg2+ and HCO3-. Almost all macrophytes, littoral invertebrates, fish and limnetic zooplankters are common tropical species. A few species are shared with dune lakes in southern Australia and even fewer are endemic. Hence, these tropical dune lakes are different from those in temperate and subtropical eastern Australia.

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Martini, Peter. "Coastal dunes of Ontario: distribution and geomorphology." Géographie physique et Quaternaire 35, no. 2 (February 1, 2011): 219–29. http://dx.doi.org/10.7202/1000438ar.

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Transverse dunes (fore-dunes), parabolic dunes, rare cliff-top dunes, and blowouts are found in Ontario. Many of these coastal dunes are land-locked on abandoned sand plains of partially drained early-post glacial lakes and seas. Others are part of coastal systems found at different stages of evolution along the Great Lakes. An idealized coastal system, as is for great part well developed at Wasaga Beach, includes the following elements: a few metres high foredunes partially deflated and breached by wave washover; low, long, narrow, marshy zones landward from the foredunes: the "pannes"; a wide sequence of numerous beach ridges capped by small (2 m high) stabilized foredunes, and separated by long shallow swales covered by water for several months of the year; intensely deflated transverse dunes which record raised coastlines of old lakes; and finally, high (up to 25 m) nested parabolic dunes showing progressive landward increase in height. These high dunes have developed over sandy, gravelly bars of early Holocene lakes, and have prograded for a short distance over lagoons. Most of the dune systems found along the Great Lakes have developed in the last 3-5000 years. Some of them have been intensely affected by man during the last two centuries, particularly by logging, agriculture, and recreational activities. Some dune fields have been completely flattened, others on the contrary have been reactivated by deforestation, and new dunes have formed and have migrated landward onto forests and cultivated fields.

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Blumer, Bradley E., Alan F. Arbogast, and Steven L. Forman. "The OSL chronology of eolian sand deposition in a perched dune field along the northwestern shore of Lower Michigan." Quaternary Research 77, no. 3 (May 2012): 445–55. http://dx.doi.org/10.1016/j.yqres.2012.01.006.

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Extensive coastal dunes occur in the Great Lakes region of North America, including northwestern Michigan where some are perched on high (~ 100 m) bluffs. This study focuses on such a system at Arcadia Dunes and is the first to systematically generate optical ages from stratigraphic sections containing buried soils. Dune growth began ca. 4.5 ka during the Nipissing high lake stand and continued episodically thereafter, with periods of increased sand supply at ca. 3.5 ka and ca. 1.7 ka. The most volumetrically dominant phase of dune growth began ca. 1.0 ka and continued intermittently for about 500 years. It may have begun due to the combined effects of a high lake phase, potential changes in lake hydrodynamics with final isostatic separation of Lake Superior from Lakes Michigan and Huron, and increased drought and hydrologic variability associated with the Medieval Warm Period. Thus, this latest eolian phase likely reflects multiple processes associated with Great Lakes water level and climate variability that may also explain older eolian depositional events. Comparison of Arcadia ages and calendar corrected 14C ages from previous studies indicate broad chronological agreement between events at all sites, although it appears that dune growth began later at Arcadia.

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Peralta Pelaez, Luis A., Patricia Moreno-Casasola, and Hugo López Rosas. "Hydrophyte composition of dune lakes and its relationship to land-use and water physicochemistry in Veracruz, Mexico." Marine and Freshwater Research 65, no. 4 (2014): 312. http://dx.doi.org/10.1071/mf12295.

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Coastal dunes include several habitats, including dune lakes. These habitats are valuable environmental assets. We analysed the impact of the surrounding land use on plant species composition, vegetation structure and water quality of 15 dune lakes in the coast of Veracruz in the Gulf of Mexico. The physical and chemical characteristics were determined for water during both the dry and rainy seasons, and vegetation was sampled once. Ammonium, nitrate, orthophosphate and total phosphorus varied between seasons and among lakes. Multivariate analysis revealed a gradient from lakes in a good state (water and wetland vegetation) to degraded lakes. These lakes fall into two groups: the first one has five lakes with a higher nutrient content, and surrounded by land where livestock is pastured and sugarcane is grown. The vegetation of these lakes consists of a combination of aquatic plants and flood-tolerant grasses introduced to feed cattle (Cynodon dactylon, Pennisetum purpureum, Setaria geniculata). Oligotrophic and mildly eutrophic lakes are characterised by little human activity, and aquatic species predominate (Cabomba palaeformis, Nymphaea ampla, Acrostichum aureum). Rural activities such as sugarcane cultivation and cattle rearing are likely the main factors causing changes in water enrichment and affecting the composition and structure of wetland vegetation. Management measures should be implemented to recover these areas and prevent further deterioration.

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Peralta Peláez, Luis Alberto, and Patricia Moreno Casasola. "Composición florística y diversidad de la vegetación de humedales en los lagos interdunarios de Veracruz." Botanical Sciences 85 (May 20, 2019): 89. http://dx.doi.org/10.17129/botsci.2307.

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Dune lakes of the coast of Veracruz, Mexico, are shallow freshwater lakes with suitable conditions for the establishment of herbaceous and arboreal wetlands. Most of the vegetation of the surrounding dunes has been transformed into pastures for grazing lands and sugar cane plantations. The objective of this paper is to describe and compare structure, composition and diversity of the wetland vegetation of 15 dune lakes in the rural area. Environmental parameters (pH, salinity, size, depth and number of dry months) were taken into account. Plant diversity of these lakes comprise 46 families (27 strictly aquatic) and 82 species, among them <em>Sagittaria lancifolia, Pontederia sagittata, Ceratophyllum demersum.</em> Species richness fl uctuated between 5 and 33 species. The classifi cation resulted in nine fl oristic wetland groups, three of them with grass species from the surrounding areas <em>(Cynodon dactylon, Echinochloa pyramidalis).</em> Ordination separated lakes based on pH and number of dry months. Management plans should be developed together with the owners to maintain both the use of these lakes and the composition and structure of their wetlands.

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Niu, Zhenmin, Nai’ang Wang, Nan Meng, Jiang Liu, Xueran Liang, Hongyi Cheng, Penghui Wen, Xinran Yu, Wenjia Zhang, and Xiaoyan Liang. "Contribution of Lake-Dune Patterning to the Dune Height of Mega-Dunes in the Badain Jaran Sand Sea, Northern China." Remote Sensing 13, no. 23 (December 3, 2021): 4915. http://dx.doi.org/10.3390/rs13234915.

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Mega-dunes in the lake group area of the Badain Jaran Sand Sea, China, are generally taller than dunes in the non-lake group area. This spatial distribution of dune heights may provide a new perspective on the controversy regarding the dunes’ formation mechanism. In this study, we calculated the relative heights and slopes of individual dunes based on a digital elevation model, and we confirmed the height distribution of abnormally tall dunes in the lake group area of the sand sea. It was also found that slopes of more than 10° in the lake group area are more common than those in the non-lake group area. Based on meteorological observations, coupled with the measurement of water content in the sand layers, we propose a conceptual model demonstrating that moisture exchange between the lakes and soil via non-rainfall water will humidify dune slopes and form a more favorable accumulation environment for aeolian sand, thus increasing dune heights. Although long-term observations are yet to be carried out, the present study can be used as evidence for understanding the basis of dune formation in the lake group area and assessing groundwater utilization in deserts.

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Liu, Zhengyao, Zhibao Dong, and Xujia Cui. "Morphometry of lunette dunes in the Tirari Desert, South Australia." Open Geosciences 10, no. 1 (September 14, 2018): 452–60. http://dx.doi.org/10.1515/geo-2018-0035.

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Abstract Morphometry and formation processes are key research problems in the study of aeolian sandy landforms. Based on morphometric parameters inferred from satellite images and the calculation of the drift potential (DP), we examined general characteristics of lunette dunes in the Tirari Desert, South Australia, along with their morphometry and formation processes to determine how this landform type initially formed and its relationship to surrounding linear dune distribution. Results show that the morphometric parameters of lunette dunes and connective lake systems exhibit moderate correlations. It suggests that the morphology of these dunes is controlled by the lakes. Spatially, the lunette dunes present regular arrangement, and the strike of their alignment are approximately in accordance with the linear dunes. The calculated DP implies that the lunette dunes developed under a low-wind-energy environment, which is a wind regime similar to that required for the formation of the surrounding linear dunes. Even though, the resultant DP demonstrates that the summer wind should be responsible for the growth of the lunette dunes. However, accompanied with the repeated drying of lakes and even its disappearance during the dune development process, it not only contributes to the development of lunette dunes but also promotes their transformation to linear dunes.

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Arthington, AH, HB Burton, RW Williams, and PM Outridge. "Ecology of humic and non-humic dune lakes, Fraser Island, with emphasis on the effects of sand infilling in Lake Wabby." Marine and Freshwater Research 37, no. 6 (1986): 743. http://dx.doi.org/10.1071/mf9860743.

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Aspects of physicochemical limnology and the zooplankton, littoral invertebrates and fish of dune lakes on Fraser Island are described and compared. The comparisons highlight differences between perched, humic lakes and the non-humic Lake Wabby, a water-table window with some morphometric and biological features typical of dune barrage lakes. Lake Wabby has been partially infilled by a mobile sand dune moving mainly in a north-westerly direction across the northern end of the lake. The maximum rate of dune advance estimated from aerial photos was 5.03 m year-1, between 1948 and 1958. Sand infilling between 1975 and 1984 altered the morphometry and substrate characteristics of the lake's eastern region and reduced maximum depth from 13.0 to 11.5 m and volume by 43%. The number of benthic invertebrates was reduced from 14 taxa in 1975 to six taxa in 1984; there was also a significant decrease in abundance of benthic Chironomini during this period (ANOVA, P < 0.05). In both years, an undescribed species of Conochironomus was the most abundant benthic invertebrate in Lake Wabby (250-700 individuals m-2). A new genus of Chironomini (near Paralauter borniella) was discovered. Lake Wabby supported 11 species of fish in 1975 and 1984, but the perched lakes had only one or two species. The five most abundant species in Lake Wabby in 1975 showed evidence of partitioning of food resources, of which the main components were benthic invertebrates and filamentous algae. Allochthonous food resources were not important in fish diets. The possible long-term effects of sand infilling on food resources, fish diets and the composition of the zooplankton in Lake Wabby are discussed.

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Bellais, Kaylyn C., Samuel T. Barber, Donald A. Beebe, and Murlene W. Clark. "Lake or Estuary? Sedimentary and Benthic Foraminiferal Characterization of a Gulf of Mexico Coastal Dune Lake." Gulf and Caribbean Research 31 (2020): SC46—SC52. http://dx.doi.org/10.18785/gcr.3101.18.

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Coastal dune lakes are shallow estuaries located within dune environments that share a permanent or intermittent connection with the sea. Because coastal dune lakes are found in few locations worldwide (e.g. Australia, New Zealand, Florida, etc.) they represent unique environments worthy of protection. However; there is a distinct lack of scientific data related to the function and ecology of coastal dune lakes, especially in the Gulf of Mexico. Therefore, the purpose of this study was to characterize the sedimentology and foraminifera of a representative coastal dune lake in Walton County, FL (i.e. Eastern Lake) and determine whether it shares geologic similarities with nearby estuaries. Ten Ekman sediment grab samples were collected along a transect spanning the length of Eastern Lake. The samples were processed to determine sedimentary properties and foraminiferal assemblages. Results from the sedimentary and foraminiferal analyses reveal 3 distinct depositional environments including: (1) a coarse grained, moderately well sorted, organic poor, sandy beach facies with both agglutinated and calcareous foraminifera, (2) a fine grained, very poorly sorted, organic rich central mud basin facies with mostly calcareous foraminifera, and (3) a coarse grained, poorly sorted, organic rich sandy marsh delta facies dominated by agglutinated foraminifera. These environments and foraminiferal patterns are also found in much larger nearby estuaries including Choctawhatchee Bay, Pensacola Bay, and Mobile Bay. Our results therefore suggest that coastal dune lakes may serve as down-scaled micro-estuaries and are functionally related to larger estuaries of the Gulf Coast despite their size.

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Lovis, William A., G. William Monaghan, Alan F. Arbogast, and Steven L. Forman. "Differential Temporal and Spatial Preservation of Archaeological Sites in a Great Lakes Coastal Zone." American Antiquity 77, no. 3 (July 2012): 591–608. http://dx.doi.org/10.7183/0002-7316.77.3.591.

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AbstractAnalysis of regional site taphonomy that incorporates depositional and postdepositional histories has become increasingly important in understanding the nature of preserved site populations and the strategies necessary for their discovery. We applied a systematic archival and field strategy directed at understanding such taphonomic processes in the coastal sand dunes of the northern and eastern Lake Michigan basin, and coupled these with a tactically directed program of OSL, 14C, and AMS dating. We demonstrate that long-term geological processes including lake level variation, episodic dune activation and stabilization, and the long-term effects of postglacial isostatic adjustments have markedly affected the potential for preservation of sites in coastal dune contexts over time and across subregions of the basin. Preservation potential for different time periods in coastal dunes is largely not synchronous with that of southern Michigan floodplains, posing substantial inferential problems. The archaeology of coastal dunes specifically, and coastal zones generally, must be used with extreme caution when cast against archaeological data from landforms with different formation processes and histories. While particularly true for the Great Lakes region, these results have implications for regional research broadly.

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Catling, Paul M., and G. Mitrow. "The dune race of Vitis riparia in Ontario: Taxonomy, conservation and biogeography." Canadian Journal of Plant Science 85, no. 2 (April 1, 2005): 407–15. http://dx.doi.org/10.4141/p03-084.

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Although poorly known, the native dune grape, Vitis riparia Michaux var. syrticola (Fernald & Wiegand) Fernald, is a potentially important source of valuable traits for the improvement of cultivated grapes. In order to clarify its taxonomic and conservation status in Ontario and to evaluate ecological and geographic patterns, data were collected from 623 specimens from 10 herbaria. In addition, five plants referable to var. syrticola with densely hairy petioles and five referable to var. riparia with glabrous petioles were cultivated in a greenhouse under uniform mesic conditions. Although the sample was considered reliable, there was no bimodal pattern in the putatively distinctive dense pubescence to support taxonomic recognition of var. syrticola; it may be referred to simply as “the dune race.” Cultivated plants retained their initial pubescence characteristics for 3 consecutive years, suggesting that the character is relatively stable. Plants referable to the dune race with dense pubescence occurred in extremely dry and open natural habitats and occurred significantly more often than expected on shoreline sand dunes of the Great Lakes. In contrast, plants without hair or less pubescent were significantly under-represented in dry habitats and shoreline dunes. While Vitis riparia is widespread in southern Ontario, the pubescent race is restricted and has a predominantly Great-Lakes-shoreline distribution pattern. It has been reported from only 43 locations and is considered vulnerable to decline. Key words: Grape, Vitis, Ontario, germplasm protection, crop relative

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Hawkins, PR, LE Taplin, LJ Duivenvoorden, and F. Scott. "Limnology of oligotrophic dune lakes at Cape Flattery, North Queensland." Marine and Freshwater Research 39, no. 4 (1988): 535. http://dx.doi.org/10.1071/mf9880535.

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Physical, chemical and biotic attributes of 16 lakes and ponds in the siliceous dunefields of Cape Flattery, in the humid tropics of Australia, have been investigated. The dune lakes are similar to those of dunefields in south-eastern Queensland, with very low to low conductivity (62-338 �S cm-1), low pH (3.9-6.8), and low to high humic content (gilvin 0.0-31.0 g440 m-1). These lakes are apparently not perched above the local water table. The ionic compositions of all lakes were very similar, with NaCl predominating and with very low concentrations of Mg, Ca, K, and SO4. Bicarbonate was absent or negligible in most lakes. The oligotrophic lakes are characterized by a desmid-diatom limnetic plankton of moderate diversity (12-35 species per lake). Of 144 taxa of phytoplankton recognized, 58% were desmids and 15% diatoms. The zooplankton was of low diversity and dominated by Calamoecia ultima. Twenty-nine species of aquatic macrophytes and 11 species of fish were recorded. Freshwater turtles (possibly Chelodina rugosa Ogilby), and the estuarine crocodile, Crocodylus porosus Schneider, were recorded from some lakes. Principal component analysis of chemical data distinguished three groups of lakes: a series of humic-stained ponds and lakes, a group of clear-water lakes with little or no humic staining, and a former barrier lagoon. Cluster analysis of the phytoplankton flora consistently segregated the clear-water lakes from humic-stained lakes but, in general, concordance of chemical, physiographic and biotic characteristics was poor. Existing classification schemes for Australian dune lakes, based on similar sets of physiographic, chemical and biotic data, do not cater well for the Cape Flattery lakes. A more useful classification may derive from consideration of the hydrological processes influencing their water balance and chemical characteristics.

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Anderton, John B., and Walter L. Loope. "Buried Soils in a Perched Dunefield as Indicators of Late Holocene Lake-Level Change in the Lake Superior Basin." Quaternary Research 44, no. 2 (September 1995): 190–99. http://dx.doi.org/10.1006/qres.1995.1063.

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AbstractA stratigraphic analysis of buried soils within the Grand Sable Dunes, a dune field perched 90 m above the southern shore of Lake Superior, reveals a history of eolian activity apparently linked with lake-level fluctuations over the last 5500 yr. A relative rise in the water plane of the Nipissing Great Lakes initially destabilized the lakeward bluff face of the Grand Sable plateau between 5400 and 4600 14C yr B.P. This led to the burial of the Sable Creek soil by eolian sediments derived from the bluff face. Subsequent episodes of eolian activity appear to be tied to similar destabilizing events; high lake levels may have initiated at least four and perhaps eleven episodes of dune building as expressed by soil burials within the dunes. Intervening low lake levels probably correlate with soil profile development, which varies from the well-developed Sable Creek Spodosol catena to thin organic layers containing in-place stumps and tree trunks. Paleoecological reconstructions available for the area do not imply enough climatic change to account for the episodic dune activity. Burial of soils by fine-fraction sediments links dune-building episodes with destabilization of the lower lake-facing bluff, which is rich in fines.

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Peterson, Curt D., and Sarah R. Doliber. "Groundwater Surface (GWS) Mapping by Ground Penetrating Radar (GPR) For Use in Protecting Freshwater Habitats, Water Quality, and Active Dune Landscapes, In the Florence Coastal Dune Sheet, Oregon, USA." Journal of Geography and Geology 11, no. 1 (February 26, 2019): 13. http://dx.doi.org/10.5539/jgg.v11n1p13.

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Ground penetrating radar (GPR) profiling was performed in the Florence (FLOR) coastal dune sheet to test relations between remotely-sensed groundwater surface (GWS) trends, measured groundwater phreatic surfaces, and overlying freshwater features/habitats. Following preliminary GPR testing, the GWS trend mapping was employed in the north FLOR dune aquifer (17 km in length and 5 km in width), in anticipation of increasing development pressures on aquifer groundwater withdrawal by the City of Florence, Oregon. Several available technologies, including continuously-towed GPR profiling (5-8 km/hr), real-time GPS positioning (±2 m horizontal), Lidar elevation control (±0.5 m NAVD88), and GIS mapping/surface trend analyses permitted upscaling to the large management area (40 km2) in the north FlOR dune aquifer. Totals of 95 km of GPR track-line, including 943 averaged shot points at 100 m track-line intervals (total ~100,000 shot points), were collected during a three-week field effort. The remotely sensed GWS, ranging from 1 to 14 m depth subsurface and 0 to 57 m elevation NAVD88, was ground-truthed in ponds, gaining-stream reaches, and monitored water wells. An area wide groundwater surface map confirmed a modeled dune-ramp aquifer, sloping (0.5-2.0 % gradients) to the Pacific Ocean shoreline and the dividing Siuslaw River valley. The continuous GPR profiles connected large dune barrage lakes, interdune valley window lakes, anadromous fish passage streams, and sensitive bog habitats to the locally-variable GWS (0.98 R2 correlation coefficient). These elevated freshwater features were shown not to be developed on perched dune soil aquitards or lake bottom mud seals, but rather they are directly dependent on the mounded, variably sloping, and very-shallow GWS in the regional dune aquifer. Shallow GWS depths also promote colonization of active dune surfaces by non-native invasive dune grasses. The freshwater lakes and ponds were shown to be susceptible to contaminant transport by down-gradient GWS flows from surrounding residential and resort development.

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Lorenz, Ralph D. "Titan's surface inventory of organic materials estimated from Cassini RADAR observations." Proceedings of the International Astronomical Union 4, S251 (February 2008): 329–30. http://dx.doi.org/10.1017/s1743921308021868.

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AbstractCassini RADAR observations now permit an initial assessment of the inventory of two classes, presumed to be organic, of Titan surface materials: polar lake liquids and equatorial dune sands. Several hundred lakes or seas have been observed, of which dozens are each estimated to contain more hydrocarbon liquid than the entire known oil and gas reserves on Earth. Dark dunes cover some 20% of Titan's surface, and comprise a volume of material several hundred times larger than Earth's coal reserves. Overall, however, the identified surface inventories (> 3 × 104 km3 of liquid, and >2 × 105 km3 of dune sands) are small compared with estimated photochemical production on Titan over the age of the Solar System. The sand volume is too large to be accounted for simply by erosion in observed river channels or ejecta from observed impact craters. The lakes are adequate in extent to buffer atmospheric methane against photolysis in the short term, but do not contain enough methane to sustain the atmosphere over geologic time. Thus, unless frequent resupply from the interior buffers this greenhouse gas at exactly the right rate, dramatic climate change on Titan is likely in its past, present and future.

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Larson, Douglas. "The Decline of Oregon's Rare Sand Dune Lakes." American Scientist 107, no. 6 (2019): 356. http://dx.doi.org/10.1511/2019.107.6.356.

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Parker, Adrian G., Andrew S. Goudie, Stephen Stokes, Kevin White, Martin J. Hodson, Michelle Manning, and Derek Kennet. "A Record of Holocene Climate Change from Lake Geochemical Analyses in Southeastern Arabia." Quaternary Research 66, no. 3 (November 2006): 465–76. http://dx.doi.org/10.1016/j.yqres.2006.07.001.

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AbstractLacustrine sediments from southeastern Arabia reveal variations in lake level corresponding to changes in the strength and duration of Indian Ocean Monsoon (IOM) summer rainfall and winter cyclonic rainfall. The late glacial/Holocene transition of the region was characterised by the development of mega-linear dunes. These dunes became stabilised and vegetated during the early Holocene and interdunal lakes formed in response to the incursion of the IOM at approximately 8500 cal yr BP with the development of C3 dominated savanna grasslands. The IOM weakened ca. 6000 cal yr BP with the onset of regional aridity, aeolian sedimentation and dune reactivation and accretion. Despite this reduction in precipitation, the lake was maintained by winter dominated rainfall. There was a shift to drier adapted C4 grasslands across the dune field. Lake sediment geochemical analyses record precipitation minima at 8200, 5000 and 4200 cal yr BP that coincide with Bond events in the North Atlantic. A number of these events correspond with changes in cultural periods, suggesting that climate was a key mechanism affecting human occupation and exploitation of this region.

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Wei, A., P. Chow-Fraser, and D. Albert. "Influence of shoreline features on fish distribution in the Laurentian Great Lakes." Canadian Journal of Fisheries and Aquatic Sciences 61, no. 7 (July 1, 2004): 1113–23. http://dx.doi.org/10.1139/f04-061.

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In this paper, we used assembled fish distributions (over 9500 field observations) and correlated them with 11 categories of the Great Lakes shoreline (i.e., bedrock, bluff, coarse beach, sandy beach dune, sandysilty bank, clay bank, low riverine coastal plain, composite, wetland, artificial, and unclassified) to validate the appropriateness of classifying Great Lakes fishes into three species complexes (taxocenes) that account for differences in their dependence on shoreline features. A χ2 goodness-of-fit test with Bonferroni correction indicated a significant positive association between the presence of fish and three shoreline classes: wetland, sandy beach dune, and bluff. The Dutilleul modified t test was used to quantify the correlation between wetlands and distribution of the 25 most abundant species and those of different functional groupings. Our results confirm that (i) the Great Lakes fish community utilizes certain shoreline features (especially wetlands) disproportionately to their availability, (ii) the distribution of wetland-associated taxa is influenced by wetland type (i.e., protected embayment versus open-shoreline wetland), and (iii) the preferred utilization of coastal wetlands by a majority of the fish community is consistent across geographical scales, from the local site to the entire Great Lakes shoreline.

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VanTassel, Nichelle M., and Alexis M. Janosik. "A compendium of Coastal Dune Lakes in Northwest Florida." Journal of Coastal Conservation 23, no. 2 (November 29, 2018): 385–416. http://dx.doi.org/10.1007/s11852-018-0671-4.

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Leimbach-Maus, Hailee B., Eric M. McCluskey, Alexandra Locher, Syndell R. Parks, and Charlyn G. Partridge. "Genetic Structure of Invasive Baby’s Breath (Gypsophila paniculata L.) Populations in a Michigan Dune System." Plants 9, no. 9 (August 31, 2020): 1123. http://dx.doi.org/10.3390/plants9091123.

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Coastal sand dunes are dynamic ecosystems with elevated levels of disturbance and are highly susceptible to plant invasions. One invasive plant that is of concern to the Great Lakes system is Gypsophila paniculata L. (perennial baby’s breath). The presence of G. paniculata negatively impacts native species and has the potential to alter ecosystem dynamics. Our research goals were to (1) estimate the genetic structure of invasive G. paniculata along the Michigan dune system and (2) identify landscape features that influence gene flow in this area. We analyzed 12 populations at 14 nuclear and two chloroplast microsatellite loci. We found strong genetic structure among populations (global FST = 0.228), and pairwise comparisons among all populations yielded significant FST values. Results from clustering analysis via STRUCTURE and discriminant analysis of principal components (DAPC) suggest two main genetic clusters that are separated by the Leelanau Peninsula, and this is supported by the distribution of chloroplast haplotypes. Land cover and topography better explained pairwise genetic distances than geographic distance alone, suggesting that these factors influence the genetic distribution of populations within the dunes system. Together, these data aid in our understanding of how invasive populations move through the dune landscape, providing valuable information for managing the spread of this species.

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Hadwen, Wade L., and Stuart E. Bunn. "Tourists increase the contribution of autochthonous carbon to littoral zone food webs in oligotrophic dune lakes." Marine and Freshwater Research 55, no. 7 (2004): 701. http://dx.doi.org/10.1071/mf04068.

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Tourists can adversely influence the ecology of oligotrophic lakes by increasing algal production via direct nutrient inputs and/or re-suspension of sediments. To assess the influence of tourists on food web dynamics, we used the natural abundance of stable isotopes of carbon and nitrogen to calculate the relative importance of autochthonous and allochthonous carbon sources to littoral zone food webs across five variously visited perched dune lakes on Fraser Island, Australia. The relative importance of autochthonous (phytoplankton and periphyton) carbon to littoral zone consumers was highly variable across taxa and lakes. Despite the potential influence of algal biomass, ambient nutrient concentrations and tannin concentrations on the contribution of autochthonous carbon to littoral zone food webs, none of these variables correlated to the per cent contribution of autochthonous carbon to consumer diets. Instead, autochthonous sources of carbon contributed more to the diets of aquatic consumers in heavily visited lakes than in less visited lakes, suggesting that tourist activities might drive these systems towards an increased reliance on autochthonous carbon. The assessment of the contribution of autochthonous carbon to littoral zone food webs may represent a more robust indicator of the impact of tourists in oligotrophic lakes than standard measures of nutrient concentrations and/or algal biomass.

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Emery, Sarah M., and Jennifer A. Rudgers. "Ecological Assessment of Dune Restorations in the Great Lakes Region." Restoration Ecology 18 (September 2010): 184–94. http://dx.doi.org/10.1111/j.1526-100x.2009.00609.x.

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Bell, C. M., and M. Suarez. "The depositional environments and tectonic development of a Mesozoic intra-arc basin, Atacama Region, Chile." Geological Magazine 130, no. 4 (July 1993): 417–30. http://dx.doi.org/10.1017/s0016756800020501.

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AbstractA thick succession of continental redbeds was deposited in a 50 km wide intra-arc basin on the Andean active continental margin in the Atacama region of northern Chile during early Cretaceous times. Upper Jurassic to early Cretaceous marine limestones were buried by the seaward progradation of a succession of coastal dunes, saline lakes and sandflats. Aeolian dune fields migrating towards the east across these coastal plains became stabilized by the growth of vegetation. Interdune alluvial areas between the sand dunes and dune fields developed into extensive alluvial braid plains which were in turn superimposed by alluvial fans. These fans were inundated by a regionally extensive saline lake produced by tectonic or volcanic damming of the sedimentary basin. This lake dried up leaving a large area of playa-lake mudflats. The climate was warm and semi-arid with a low and seasonal rainfall. Parts of the area supported a substantial vegetation of woody plants, together with a vertebrate fauna of dinosaurs, pterosaurs and crocodiles. The continental redbeds were derived from a volcanic source and were deposited on continental crust in a deep but narrow, north-south elongated, fault-bounded graben. This extensional basin formed in an intra-arc setting within an active andesitic volcanic chain. Upwards-coarsening sedimentary successions were the product of uplift of the fault-bounded margins of the basin.

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Bowling, LC. "Optical properties, Nutrients and Phytoplankton of freshwater Coastal Dune Lakes in South-east Queensland." Marine and Freshwater Research 39, no. 6 (1988): 805. http://dx.doi.org/10.1071/mf9880805.

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Gilvin was the main attenuator of photosynthetically available radiation (PAR) in 26 freshwater coastal dune lakes, despite most being only slightly humic (range 0.000-27.866 m-1, median = 1.088 m-1). Most were also non-turbid [range 0.27-3.00 nephelometric turbidity units (NTU), median = 0.77 NTU] and had low concentrations of chlorophyll a (range 0.212-15.869 �g I-1, median = 3.285 �g I-1). Accordingly there was only slight to moderate attenuation of PAR in most lakes, the majority having mean downwelling vertical attenuation coefficients of less than 1.0 m-1. However, Secchi depths indicate that the lake waters were more transparent during this study than previously reported in the literature. The lakes were typically oligotrophic, acidic, and of low conductivity. Desmids and Peridinium spp. dominated the phytoplankton, although Dynobryon cylindricum Imhof. and various Chlorococcales were also common.

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Kofron, Christopher P. "The Dune Lakes in central coastal California: Why are they dry?" Lakes & Reservoirs: Research & Management 24, no. 2 (April 15, 2019): 190–94. http://dx.doi.org/10.1111/lre.12261.

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Peralta-Peláez, Luis A., Patricia Moreno-Casasola, and Iris Neri-Flores. "Management and restoration of dune lakes in Veracruz, Gulf of Mexico." Journal of Coastal Conservation 23, no. 2 (January 4, 2019): 445–60. http://dx.doi.org/10.1007/s11852-018-0674-1.

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Hadwen, Wade L., Angela H. Arthington, and Thorsten D. Mosisch. "The impact of tourism on dune lakes on Fraser Island, Australia." Lakes and Reservoirs: Research and Management 8, no. 1 (March 2003): 15–26. http://dx.doi.org/10.1046/j.1440-1770.2003.00205.x.

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English, Jeremy P., and Timothy D. Colmer. "Tolerance of extreme salinity in two stem-succulent halophytes (Tecticornia species)." Functional Plant Biology 40, no. 9 (2013): 897. http://dx.doi.org/10.1071/fp12304.

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Communities of Tecticornia on the margins of ephemeral salt lakes in Australia often exhibit species zonation, such as at Hannan Lake (Western Australia) where Tecticornia indica subsp. bidens (Nees) K.A.Sheph. and Paul G.Wilson occupies the less saline dune habitat on lake margins and Tecticornia pergranulata (J.M.Black) K.A.Sheph. and Paul G.Wilson subsp. pergranulata occupies both the dunes and the more saline and moist lake playa. Here we tested the hypothesis that these two species differ in tolerance to extreme salinity. Plants were grown in drained sand cultures with treatments of 10–2000 mM NaCl for 85 days. Both species were highly salt tolerant, maintaining growth at treatments of up to 2000 mM NaCl, although the death of two replicates of T. indica at 2000 mM NaCl suggests this salinity is close to the species tolerance limit. Both Tecticornia species maintained a favourable gradient in tissue water potential via osmotic adjustment as external salinity increased, also with reduced tissue water content at very high external salinity. Regulated accumulation of Na+ and Cl–, maintenance of net K+ to Na+ selectivity, high tissue concentrations of glycinebetaine and presumed cellular solute compartmentation, would have contributed to salt tolerance. The growth rate of T. pergranulata was 11–29% higher than T. indica suggesting, in addition to these moderate differences in salinity tolerance, other factors are likely to contribute to species zonation at salt lakes. The higher water use efficiency of the C4 T. indica compared with the C3 T. pergranulata may provide an advantage in the drier dune habitat on salt lake margins. An additional experiment confirmed the hypothesis that survival of T. pergranulata seedlings is enhanced by the duration of reduced salinity after germination, as would occur following significant rainfall, as older seedlings maintained higher growth rates during subsequent increases in salinity.

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Norris, RH, JL Moore, WA Maher, and LP Wensing. "Limnological characteristics of two coastal Dune Lakes, Jervis Bay, South Eastern Australia." Marine and Freshwater Research 44, no. 3 (1993): 437. http://dx.doi.org/10.1071/mf9930437.

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Limnological features of two permanent, closed, coastal dune lakes that are separated by only about 400 m are reported. The depth of Lake Windermere fluctuated by about 7 m during this study (1982- 1988); however, fluctuations up to 15 m were observed between 1970 and 1988. Lake Windermere is exposed to wind mixing, is transparent and is usually mixed, or only weakly stratified. Lake McKenzie is semi-perched, darkly coloured and strongly stratified with an anoxic hypolimnion during summer. It is about one fifth of the surface area and half the depth of Lake Windermere and protected from wind mixing. Both lakes are acidic and have low salinity, and the dominant ions are sodium and chloride probably from precipitation of marine aerosols. Oxygen depletion in the hypolimnion of both lakes indicates a substantial organic load, the source of which is allochthonous material from the catchment rather than autochthonous material. Lake Windermere had higher densities of zooplankton (mostly Calamoecia tasmanica) than Lake McKenzie, but the latter lake had higher numbers of the predaceous Chaoborus sp. Lake McKenzie had higher invertebrate densities than Lake Windermere and these fluctuated widely between years, corresponding with variation in rainfall. Mayflies and chironomids were numerically dominant in Lake McKenzie, and caddisflies and chironomids were numerically dominant in Lake Windermere. Turtle and odonate predators were more common in Lake McKenzie than in Lake Windermere. It is postulated that biological interactions are more important in shaping the communities in Lake McKenzie and physical factors such as wave action are more important in Lake Windermere.

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Welch, Brian C., Robert W. Jacobel, and Steven A. Arcone. "First results from radar profiles collected along the US-ITASE traverse from Taylor Dome to South Pole (2006–2008)." Annals of Glaciology 50, no. 51 (2009): 35–41. http://dx.doi.org/10.3189/172756409789097496.

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AbstractThe 2006/07 and 2007/08 US-ITASE traverses from Taylor Dome to South Pole in East Antarctica provided opportunities to survey the subglacial and englacial environments using 3 MHz and 200MHz radar. We present first results of these new ground-based radar data. A prominent basal deformation layer indicates different ice-flow regimes for the northern and southern halves of the Byrd Glacier drainage. Buried dune stratigraphy that appears to be related to the megadunes towards the west occurs at depths of up to 1500 m. At least two new water-filled subglacial lakes were discovered, while two recently drained lakes identified from repeat ICESat surface elevation surveys appear to be devoid of water.

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Van Nieukerken, Erik J., and Anders N. Nilsson. "The third-instar larva of the water beetle Coelambus nigrolineatus (Steven) (Coleoptera: Dytiscidae)." Insect Systematics & Evolution 16, no. 1 (1985): 1–4. http://dx.doi.org/10.1163/187631285x00018.

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AbstractThe third-instar Iarva of Coelambus nigrolineatus (Steven, 1808) (= C. lautus (Schaum, 1843)) is described from material collected in artificial dune-lakes in the Netherlands. The larva is characterized by legs with swimming hairs and long urogomphi with numerous secondary setae. In these characters it resembles the larva of C. confluens (Fabricius), from which it can be separated on the narrower frontal projection of the head and the relatively shorter hindclaws.

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Fisher, Timothy G., Jennifer Horton, Kenneth Lepper, and Henry Loope. "Aeolian activity during Late Glacial time, with an example from Mongo, Indiana, USA." Canadian Journal of Earth Sciences 56, no. 2 (February 2019): 175–82. http://dx.doi.org/10.1139/cjes-2018-0127.

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The last aeolian activity of a significant number of inland sand dunes in the southern Great Lakes region (SGLR) was several thousands of years after deglaciation. At Mongo, Indiana, a field of parabolic sand dunes with a variety of morphologies are within the channel bottom of the Pigeon River meltwater channel, with some dunes having climbed up the channel wall onto the adjacent upland surface. The optically stimulated luminescence (OSL) samples from the channel-bottom dunes have a mean age of 14.2 ± 1.6 ka (n = 2) and the OSL samples from upland dunes have a mean age of 12.3 ± 1.6 ka (n = 4). Dunes and outwash ages and geomorphic setting constrain both the position of the Huron-Erie and Saginaw lobes. The oldest dune age is also a minimum age for cessation of local meltwater flow from the Huron-Erie Lobe of the Laurentide Ice Sheet and formation of the adjacent Sturgis Moraine of the Saginaw Lobe. The final activity of the dunes is coincident with late glacial stadial and interstadial events as recorded in the Greenland ice core records, a similar finding to all other studies of dunes in the SGLR. It is now well recognized that many dunes were last active before, during, and after the Younger Dryas stadial, presumably in response to a climate that was windier and less favorable for vegetation.

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Stephens, Tom, Paul Augustinus, Brett Rip, Patricia Gadd, and Atun Zawadski. "Managing land-use effects on Northland dune lakes: lessons from the past." New Zealand Journal of Marine and Freshwater Research 52, no. 3 (February 4, 2018): 409–29. http://dx.doi.org/10.1080/00288330.2018.1430593.

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36

Zhang, Jianhua, and M. Anwar Maun. "Potential for seed bank formation in seven Great Lakes sand dune species." American Journal of Botany 81, no. 4 (April 1994): 387–94. http://dx.doi.org/10.1002/j.1537-2197.1994.tb15461.x.

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37

Ball, OJ-P., SR Pohe, and MJ Winterbourn. "Littoral macroinvertebrate communities of dune lakes in the far north of New Zealand." New Zealand Journal of Marine and Freshwater Research 49, no. 2 (April 2, 2015): 192–204. http://dx.doi.org/10.1080/00288330.2014.989237.

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38

Echaniz, Santiago, Alicia Vignatti, Javier Schlegel, and Nicolás Schiel. "ZOOPLANKTON OF TWO SHALLOW LAKES IN THE SOUTH OF MEAUCO FORMATION (LA PAMPA PROVINCE, ARGENTINA)." Semiárida Revista de la Facultad de Agronomía UNLPam 30, no. 2 (October 1, 2020): 9–18. http://dx.doi.org/10.19137/semiarida.2020(02).09-18.

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The Meauco Formation, a dune region of the central Pampa province, has numerous shallow lakes. Although there is hydrological information about them, it is very scarce about their limnological characteristics. The objectives are to know the physical-chemical and zooplankton parameters of two nearby shallow lakes, with and without fishes: Santa Isabel I (SI I) and Santa Isabel II (I II) respectively, and determine the influence of zooplankton on phytoplankton biomass and transparency. It was sampled during 2018 and 2019. In both the mean salinity were less than 1g.L-1 and the Secchi disk depth was around 0.45m. The chlorophyll concentrations varied between 9.32 and 11.63 mg.m-3. Seven cladocerans, 4 copepods and 20 rotifers were recorded. Most of the taxa were shared by both lakes, however, 20 rotifers were recorded in SI I and 13 in SI II. The total zooplankton density did not differ, but SI I had greater abundance of rotifers (69% of total) and SI II of crustaceans (72%). The presence of fish influences the zooplankton composition but its small size, even in the absence of fish, makes it have little influence on the phytoplankton; therefore, no differences were found in the transparency and phytoplankton biomass of both lakes.

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Pickart, Andrea J. "Ammophila Invasion Ecology and Dune Restoration on the West Coast of North America." Diversity 13, no. 12 (November 30, 2021): 629. http://dx.doi.org/10.3390/d13120629.

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The invasive ecosystem engineer Ammophila arenaria, native to Europe, was first introduced to California (USA) in 1896. More than a century later, it has come to dominate coastal foredune vegetation on the west coast of North America to the near exclusion of native species. A. arenaria builds a narrow, steep, peaked, and densely vegetated foredune, in contrast to the broad, more sparsely vegetated foredunes built by the native Elymus mollis. As such, it has modified dune processes by fixing the foredune and disrupting exchange of sediment between the beach, foredune, and dunefield. In the 1930s the congener A. breviligulata, native to the east coast and Great Lakes USA, was first introduced to Oregon, and has been displacing A. arenaria in southern Washington. Ammophila spp. have drastically reduced biodiversity, outcompeting native plant species, and displacing both invertebrate and vertebrate species. Restoration of west coast dunes through the removal of Ammophila began in the 1990s. Methods usually consist of one or a combination of manual digging, burning/herbicides, or excavation with heavy equipment. There are benefits and disadvantages to each method. Manual removal has proven most effective at restoring foredune form and process but is expensive. Excavation and herbicides may result in the loss of foredune morphology. Managers must articulate goals carefully before selecting restoration methods.

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Outridge, P. M., A. H. Arthington, and G. J. Miller. "Limnology of naturally acidic, oligotrophic dune lakes in subtropical Australia, including chlorophyll — phosphorus relationships." Hydrobiologia 179, no. 1 (July 1989): 39–51. http://dx.doi.org/10.1007/bf00011928.

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Lichter, John. "AMS Radiocarbon Dating of Lake Michigan Beach-Ridge and Dune Development." Quaternary Research 48, no. 1 (July 1997): 137–40. http://dx.doi.org/10.1006/qres.1997.1904.

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Strandplains of shore-parallel beach ridges bordering the Great Lakes are valuable for reconstructing histories of climate-related lake-level fluctuations. However, imprecise radiocarbon dates of ridge formation have frustrated development of dependable chronologies from which information about variation in the frequency of ridge formation and inferred climate fluctuations can be obtained. The resolution and precision of radiocarbon chronologies can be improved with AMS 14C dates of roots and rhizomes of plant species associated with the formation and growth of the sand-dune caps of breach ridges. These dates reliably estimate the timing of shore progradation when the base of the previously established beach ridge becomes inundated by the water table. An AMS radiocarbon chronology of beach-ridge formation in northern Lake Michigan shows that information about variation in the frequency of ridge formation is important for paleoclimatic interpretation.

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42

Yang, Xiaoping, Nina Ma, Jufeng Dong, Bingqi Zhu, Bing Xu, Zhibang Ma, and Jiaqi Liu. "Recharge to the Inter-Dune Lakes and Holocene Climatic Changes in the Badain Jaran Desert, Western China." Quaternary Research 73, no. 1 (January 2010): 10–19. http://dx.doi.org/10.1016/j.yqres.2009.10.009.

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We present new estimates on evaporation and groundwater recharge in the Badain Jaran Desert, western Inner Mongolia of northwestern China, based on a modified Penman Equation suitable for lakes in China. Geochemical data and water balance calculations suggest that local rainfall makes a significant contribution to groundwater recharge and that past lake-level variations in this desert environment should reflect palaeoclimatic changes. The chronology of lake-level change, established by radiocarbon and U-series disequilibrium dating methods, indicates high lake levels and a wetter climate beginning at ca. 10 ka and lasting until the late mid-Holocene in the Badain Jaran Desert. The greatest extension of lakes in the inter-dune depressions indicates that the water availability was greatest during the mid-Holocene. Relicts of Neolithic tools and pottery of Qijia Culture (2400–1900 BC) suggest relatively intensive human activity in the Badain Jaran Desert during the early and middle Holocene, supporting our interpretation of a less harsh environment. Wetter climates during the Holocene were likely triggered by an intensified East Asian summer monsoon associated with strong insolation.

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Arthington, A. H., G. J. Miller, and P. M. Outridge. "Water Quality, Phosphorus Budgets and Management of Dune Lakes Used for Recreation in Queensland (Australia)." Water Science and Technology 21, no. 2 (February 1, 1989): 111–18. http://dx.doi.org/10.2166/wst.1989.0036.

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The water quality and trophic status of two Queensland dune lakes are compared in the context of assessing the impacts of recreational use and other human activities. Lake Freshwater, Cooloola, has a mean total phosphorus concentration of 12.1 ± 3.3 µg l−1 and is approaching mesotrophic status, whereas Blue Lagoon, Moreton Island, is oligotrophic. Natural loadings of total phosphorus, ranging from 0.2 to 0.35 g m−2 yr−1, are consistent with the progression of Lake Freshwater from oligotrophic to mesotrophic status. The phosphorus loadings predicted by Vollenweider's (1976) one-compartment model, for two values of mean lake depth, also indicate that Lake Freshwater is tending towards eutrophic conditions. The management implications of phosphorus loadings and budgets are discussed.

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Wright, Ian, and Peter Cranston. "Are Australian lakes different? — Chironomid and chaoborid exuviae from Lake McKenzie, a coastal temperate dune lake." SIL Proceedings, 1922-2010 27, no. 1 (April 2000): 303–8. http://dx.doi.org/10.1080/03680770.1998.11901243.

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Van der Meeren, Thijs. "Late Holocene paleohydrological changes from dune-associated lakes in western Mongolia as windows to westerly dynamics." Quaternary International 279-280 (November 2012): 512. http://dx.doi.org/10.1016/j.quaint.2012.08.1768.

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Rowe, David K., and Benjamin L. Chisnall. "Environmental factors associated with the decline of dwarf inangaGalaxias gracilis McDowall in New Zealand dune lakes." Aquatic Conservation: Marine and Freshwater Ecosystems 7, no. 4 (December 1997): 277–86. http://dx.doi.org/10.1002/(sici)1099-0755(199712)7:4<277::aid-aqc248>3.0.co;2-q.

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Garces, Kylea R., Haley E. Sage, Natalie Christian, and Sarah M. Emery. "Epichloë Increases Root Fungal Endophyte Richness and Alters Root Fungal Endophyte Composition in a Changing World." Journal of Fungi 8, no. 11 (October 28, 2022): 1142. http://dx.doi.org/10.3390/jof8111142.

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Plants harbor a variety of fungal symbionts both above- and belowground, yet little is known about how these fungi interact within hosts, especially in a world where resource availability is changing due to human activities. Systemic vertically transmitted endophytes such as Epichloë spp. may have particularly strong effects on the diversity and composition of later-colonizing symbionts such as root fungal endophytes, especially in primary successional systems. We made use of a long-term field experiment in Great Lakes sand dunes to test whether Epichloë colonization of the dune-building grass, Ammophila breviligulata, could alter fungal root endophyte species richness or community composition in host plants. We also tested whether nitrogen addition intensified the effects of Epichlöe on the root endophyte community. We found that Epichloë increased richness of root endophytes in Ammophila by 17% overall, but only shifted community composition of root endophytes under nitrogen-enriched conditions. These results indicate that Epichlöe acts as a key species within Ammophila, changing richness and composition of the root mycobiome and integrating above- and belowground mycobiome interactions. Further, effects of Epichloë on root endophyte communities were enhanced by N addition, indicating that this fungal species may become even more important in future environments.

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48

RIOUAL, PATRICK, ROGER J. FLOWER, GUOQIANG CHU, YANBIN LU, ZHONGYAN ZHANG, BINGQI ZHU, and XIAOPING YANG. "Observations on a fragilarioid diatom found in inter-dune lakes of the Badain Jaran Desert (Inner Mongolia, China), with a discussion on the newly erected genus Williamsella Graeff, Kociolek & Rushforth." Phytotaxa 329, no. 1 (November 24, 2017): 28. http://dx.doi.org/10.11646/phytotaxa.329.1.2.

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Populations of a fragilarioid diatom from inter-dune lakes of the Badain Jaran Desert (northern China), originally identified and reported under the name Fragilaria sp. cf. famelica, were investigated in detail using light and scanning electron microscopy. The analyses indicate that most of the morphological features of this taxon are identical to Williamsella angusta Graeff, Kociolek & S.R. Rushforth, the type species of the genus Williamsella recently described from Blue Lake warm spring (Utah, USA). The criteria used to separate Williamsella from Fragilaria (i.e. the presence/absence of spines, the colonial formation, the preference for saline vs freshwater habitat, and the coverings of the areolae) are not supported and the genus is refuted. Instead the new combination Fragilaria crenophila comb. nov. is proposed for the Blue Lake species. The taxon from the Badain Jaran desert lakes represents a varietal population that is characterized by shorter valve length and lower stria density than the nominal variety, and is given the name Fragilaria crenophila var. sinensis. A discussion of the taxonomy, ecology and geographical distribution of this taxon is presented and a detailed comparison with Fragilaria asiatica Hustedt, a very similar species described from northern Tibet (China) is made.

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Wriston, Teresa, and Geoffrey M. Smith. "Late Pleistocene to Holocene history of Lake Warner and its prehistoric occupations, Warner Valley, Oregon (USA)." Quaternary Research 88, no. 3 (September 5, 2017): 491–513. http://dx.doi.org/10.1017/qua.2017.59.

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AbstractDuring the late Pleistocene, Warner Valley (Oregon, USA) was filled by Lake Warner; however, little is known about its rise and fall and how its changing lake levels effected the distribution of the valley’s earliest occupants. The discovery of Paleoindian projectile points along ancient shorelines of the lake spurred us to examine them for geochronological controls to aid in constructing the lake’s history. We found that Lake Warner filled the valley floor between ca. 30,000 and 10,300 cal yr BP, probably reaching its maximum ca. 17,000–16,100 cal yr BP before it began to recede. People arrived with Clovis and Western Stemmed Tradition (WST) projectile points before ca. 12,800 cal yr BP, around the time the lake stalled in its retreat. When the lake continued its decline, people using WST points followed it southward into the valley floor, where dune-and-slough topography began developing ca. 10,300 cal yr BP in response to episodic wetting and drying during the early Holocene. By the time Mazama tephra fell, ca. 7600 cal yr BP, the once large lake was divided into a series of small lakes, ponds, and sloughs that attracted people to their abundant resources of endemic fish and marsh plants.

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Simpson, Claire E., Christopher D. Arp, Yongwei Sheng, Mark L. Carroll, Benjamin M. Jones, and Laurence C. Smith. "Landsat-derived bathymetry of lakes on the Arctic Coastal Plain of northern Alaska." Earth System Science Data 13, no. 3 (March 19, 2021): 1135–50. http://dx.doi.org/10.5194/essd-13-1135-2021.

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Abstract. The Pleistocene sand sea on the Arctic Coastal Plain (ACP) of northern Alaska is underlain by an ancient sand dune field, a geological feature that affects regional lake characteristics. Many of these lakes, which cover approximately 20 % of the Pleistocene sand sea, are relatively deep (up to 25 m). In addition to the natural importance of ACP sand sea lakes for water storage, energy balance, and ecological habitat, the need for winter water for industrial development and exploration activities makes lakes in this region a valuable resource. However, ACP sand sea lakes have received little prior study. Here, we collect in situ bathymetric data to test 12 model variants for predicting sand sea lake depth based on analysis of Landsat-8 Operational Land Imager (OLI) images. Lake depth gradients were measured at 17 lakes in midsummer 2017 using a Humminbird 798ci HD SI Combo automatic sonar system. The field-measured data points were compared to red–green–blue (RGB) bands of a Landsat-8 OLI image acquired on 8 August 2016 to select and calibrate the most accurate spectral-depth model for each study lake and map bathymetry. Exponential functions using a simple band ratio (with bands selected based on lake turbidity and bed substrate) yielded the most successful model variants. For each lake, the most accurate model explained 81.8 % of the variation in depth, on average. Modeled lake bathymetries were integrated with remotely sensed lake surface area to quantify lake water storage volumes, which ranged from 1.056×10-3 to 57.416×10-3 km3. Due to variations in depth maxima, substrate, and turbidity between lakes, a regional model is currently infeasible, rendering necessary the acquisition of additional in situ data with which to develop a regional model solution. Estimating lake water volumes using remote sensing will facilitate better management of expanding development activities and serve as a baseline by which to evaluate future responses to ongoing and rapid climate change in the Arctic. All sonar depth data and modeled lake bathymetry rasters can be freely accessed at https://doi.org/10.18739/A2SN01440 (Simpson and Arp, 2018) and https://doi.org/10.18739/A2HT2GC6G (Simpson, 2019), respectively.

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Journal articles on the topic 'Dune lakes'

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