杏吧原创

V谩zquez-Riveiros, N.A., Babalola, A.O., Boudreau, R.E.A., Patterson, R.T., Roe, H.M., Doherty, C., 2007. Modern distribution of saltmarsh foraminifera and thecamoebians in the Seymour-Belize Inlet Complex, British Columbia, Canada.聽Quaternary Land-Ocean Interactions: Sea-Level Change, Sediments and Tsunami.聽Marine Geology 242 (1-3): 39-63.聽https://doi.org/10.1016/j.margeo.2006.08.009

Foraminifera and thecamoebian distribution along two marsh transects, in the Waump (WIR 16) and Wawwat鈥檒 (WIR 12) Indian Reserves, in the Seymour鈥揃elize Inlet Complex, north coastal British Columbia were investigated. Based on Q- and R-mode cluster analysis of the faunal distributions three high abundance, low diversity faunal assemblages were identified; the Freshwater, Brackish and High Salt Marsh Assemblages. The Freshwater Assemblage is dominated by the soil thecamoebian species Cyclopyxis kahli, a significant presence of centropyxids and Nebela collaris. The Brackish Assemblage is characterized by abundant centropyxids and less than 10% foraminifera. The High Salt Marsh Assemblage is characterized by the dominance of Balticammina pseudomacrescens. The results of this study show the high potential of combined thecamoebian/foraminifera analyses for paleo-sea level research under lower salinity marsh conditions.

Stolze, S., Roe, H.M., Patterson, R.T., 2007. Review of lateglacial vegetation and climate change from Woods Lake, Seymour Inlet, Coastal British Columbia, Canada. Reviews of Palynology and Palaeobotany. 147 (1-4):112-127.聽https://doi.org/10.1016/j.revpalbo.2007.07.002

The Lateglacial and Holocene vegetation and environmental history recorded in a small coastal lake in the Seymour Inlet area, British Columbia, is described. Pinus-dominated vegetation and a cool and moist climate prevailed in the early phase of the Lateglacial. Later stages of the Lateglacial were characterised by a mixed coniferous forest with Tsuga species, Picea and Abies and slightly warmer conditions and increased moisture. Alnus, Picea and Pteridium aquilinum dominated the vegetation of the early Holocene. Warmer and drier conditions prevailed during this phase. Increased moisture and decreased temperatures characterised the mid-Holocene as indicated by the dominance of Cupressaceae, Tsuga heterophylla, Alnus and Picea in the forest around the study site. This represented a transitional stage to the late-Holocene Cupressaceae鈥揟. heterophylla phase, when the modern climate regime characterised by temperate and wet conditions became established. The vegetation succession identified correlates well with Lateglacial and Holocene records from other sites in the Coastal Western Hemlock biogeoclimatic zone of British Columbia. Sedimentological and microfossil records from the examined sediment core indicate that saltwater intrusions into the lake basin occurred during the early Lateglacial and the middle to late Holocene resulting from changes in relative sea level.

Keywords: pollen analysis; Lateglacial and Holocene; vegetation history; palaeoclimate; Coastal Western Hemlock biogeoclimatic zone; British Columbia

Galloway, J.M., Patterson, R.T., Doherty, C.T., Roe, H.M. 2007. Post-glacial vegetation and climate history of two frog Lake, Central Coastal Mainland, British Columbia, Journal of Paleolimnology. 38 (4): 569-588.聽https://doi.org/10.1007/s10933-007-9091-4

Pollen and diatoms preserved in the radiocarbon dated sediments of Two Frog Lake in聽the Seymour-Belize Inlet Complex of the central mainland coast of British Columbia document postglacial climate change. Two Frog Lake was isolated from the sea prior to 11,040 卤 50 yr BP (13,030 cal. yr BP) when the climate was cool and dry, and open Pinus contorta woodlands covered the landscape. These woodlands were replaced by聽a mixed conifer forest ca. 10,200 yr BP (ca. 12,300 cal. yr BP) when the climate became moister. A relatively dry and warm early Holocene climate allowed Pseudotsuga menziesii to migrate northward to this site where it grew with Picea, Tsuga heterophylla and Alnus. The climate became cooler and moister at ca. 8,000 yr BP (ca. 9,200 cal. yr BP), approximately 500鈥�1,000 years prior to sites located south of Two Frog Lake and on the Queen Charlotte Islands, but contemporary with sites on the northern mainland coast of British Columbia and south coastal Alaska. Climate heterogeneity in central coastal British Columbia appears to have occurred on a synoptic scale, suggesting that atmospheric dynamics linked to a variable Aleutian Low pressure system may have had an important influence on early Holocene climate change in the Seymour-Belize Inlet Complex. The transition to cooler and moister conditions facilitated the expansion of Cupressaceae and the establishment of a modern-type coastal temperate rainforest dominated by Cupressaceae and T. heterophylla. This was associated with progressive lake acidification. Diatom changes independent of vegetation change during the late Holocene are correlative with the mid-Neoglacial period, when cooler temperatures altered diatom communities.

Chang, A.S., Patterson, R.T. 2007. Corrigendum to 鈥淐limate shift at 4400 years BP: Evidence from high-resolution diatom stratigraphy, Effingham Inlet, British Columbia, Canada鈥漑Palaeogeography, Palaeoclimatology, Palaeoecology 226 (2005) 72鈥�92]聽 Palaeogeography, Palaeoclimatology, Palaeoecology 243: 471-473.

The revisions as of 27 March 2006 in Section 5.4 鈥淚nterannual diatom abundance and assemblages鈥� are as follows:

Error in calculating absolute abundances in samples S8-58, S8-59, and S8-60: must multiply originally published abundances by a factor of 10. Therefore, calculated averages and maxima are corrected as follows:

Mean abundance of diatoms counted from all 67 samples: 5.1脳108 valves/g.
Mean abundance of Chaetoceros resting spores (CRS), all samples: 1.4脳108 valves/g
Mean diatom abundance in thicker varves (samples S8-42 to S8-67): 7.0脳108 valves/g
Mean CRS abundance in thicker varves: 1.7脳108 valves/g
Maximum Skeletonema costatum absolute abundance: 1.7脳109 valves/g
Average brackish/benthic diatoms in thicker varves: 4.7脳107 valves/g.

The presence of the unknown morphology in varve 8 (sample S8-60) only affected the semi-qualitative description of laminae in thin section. The discussion about the unknown morphology diluting the diatom signal from the quantitative slide can be disregarded.
All other descriptions, discussions and interpretations remain the same as previously published. Figs. 2 and 5 have been revised.

Patterson, R.T., Prokoph, A., Reinhardt, A., Roe, H.M. 2007. Climate cyclicity in late Holocene anoxic marine sediments from the Seymour-Belize Inlet Complex, British Columbia.聽Quaternary Land-Ocean Interactions: Sea-Level Change, Sediments and Tsunami.聽Marine Geology, 242 (1-3): 123-140.聽https://doi.org/10.1016/j.margeo.2007.04.003

An 8.72 m late Holocene sediment core (VEC02A07) obtained from Alison Sound in the Belize鈥揝eymour Inlet Complex of central British Columbia, Canada was deposited between 鈭�3500鈥�1000 yr BP under primarily anoxic marine conditions. This core聽contains a detailed cyclic record of land鈥搒ea interactions as evidenced by significant fluctuations in marine primary productivity and changes in the supply of terrigenous material that can be related to long term variation in the relative influence of the Aleutian聽Low (AL) and North Pacific High (NPH).

Sedimentologically, the core is characterized by alternating intervals of fine-grained massive intervals (70%), laminated intervals (23%), turbidites (5%) and graded silt鈥揷lay layers (2%). The laminated intervals are comprised of couplets that vary between light-coloured, diatom-rich layers, deposited primarily during the summer months, and dark-coloured, mineral-rich layers deposited during winter. Laminated couplets are most common in portions of the core deposited between ~3150 and 2700 yr BP,聽which corresponds to an episode of regional neoglaciation.

Time-series analysis was carried out on high-resolution particle size measurements obtained from core sub-samples and on sediment grey-scale colour variability derived from X-ray scans of the core. Non-linear time-series analyses revealed that the聽succession of massive and laminated sedimentation displayed characteristics of self-organization following a power law relationship for core length segments of <13 cm (M~50 years of deposition). Wavelet and spectral time-series analysis indicated that core length segments of >13 cm (>~50 years of deposition) contained evidence of sedimentary depositional cycles of ~70鈥�96, 135鈥�155 and 250鈥�330 years that reflect changes in AL and NPH mediated regional precipitation patterns that can in turn be related to larger-scale climate drivers such as the Pacific Decadal Oscillation (PDO) or solar irradiance cyclicity.

Keywords: NE Pacific; laminated marine sediments; wavelet transformation; climate cyclicity; image analysis; climate change

Roe, H.M.,聽Patterson, R.T. 2006. Distribution of thecamoebians (testate amoebae) in small lakes and ponds, Barbados, West Indies. Journal of Foraminiferal Research 36: 116-134.

Thecamoebian faunas identified from 15 small permanent and ephemeral lakes and ponds on Barbados, West Indies, are characterized by low numbers of individuals and low species diversities (Shannon-Wiener Diversity Index 5 0鈥�1.4). Four lakes and ponds were found to contain no thecamoebians. The faunas were dominated by Centropyxis aculeata, with lesser numbers of Arcella vulgaris, Cucurbitella tricuspis, Centropyxis constricta and Cyclopyxis kahli. Very low numbers of the small idiosomic species Euglypha rotunda and an undifferentiated Corythion-Trinema type were also reported; the first records from a tropical region. Centropyxid dominated faunas have been reported from other tropical areas and may indicate stressed environmental conditions. Additional important ecological controls on these faunas include substrate characteristics, the nature of bankside and aquatic vegetation and water depth. Land use characteristics do not appear to have a significant influence on faunal distribution, although the soil indicator thecamoebian species C. kahli seems to have been introduced into at least one pond through erosion from adjacent fields. Significant numbers of the salt marsh foraminiferid Jadammina macrescens, and lesser numbers of Polysaccammina ipohalina and Miliammina fusca, were found in one coastal pond, with a few specimens of J. macrescens found in another. The presence of this unusual, nonmarine foraminiferal fauna may relate to the intrusion of salt water into local ground waters, or possibly the introduction of sea salt from the prevailing Atlantic winds. Foraminiferal and thecamoebian colonization into the ponds may have been avian mediated.

Patterson, R.T., Fowler, A.D., Huber, B., 2005. ERRATA: 鈥淓vidence of Hierarchical Organization in the Planktic Foraminiferal Evolutionary Record. 聽 Journal of Foraminiferal Research. 2004, 32 (2) 85-95鈥�, Journal of Foraminiferal Research, 35 (1):83.聽doi:10.2113/35.1.83

Some errors have been noted in the biostratigraphic ranges and spelling of some species plotted in Appendix 1. These errors primarily came about as the result of transcription errors introduced during manual creation of the charts from the parent electronic biostratigraphic database. As part of this revision, six species subsequently recognized to be synonymous have been deleted and the ranges of a few species have been revised (mostly small changes) to reflect recent taxonomic revisions. To determine whether the results of Patterson and others (2004) would be influenced by these changes, the evolutionary data were reanalyzed. The resulting wavelet patterns for speciation and extinction are identical to those published. This result is not surprising since the synonymous deleted species had similar ranges to those retained, and most other species range changes were minor. Thus, the conclusions presented by Patterson and others (2004) have not been influenced by the changes made here. A revised Appendix 1 in portable document format (pdf) is available for download from the Journal of Foraminiferal Research Data Repository (item number JFR DR200501) at: http://cushforams.niu.edu/JFRdata.htm. Species that have been changed in Appendix 1 are listed below.

Kumar, A., Patterson, R.T. 2005. 聽 Foraminiferal Evidence of Subaqueous debris flows at ODP Site 1033 (Leg 169S), Saanich Inlet, Vancouver Island, Canada. 聽 Journal of the Palaeontological Society of India Golden Jubilee Volume 50: 121-134.

The foraminiferal faunas of 150 Holocene-latest Pleistocene samples from ODP Site 1033 (Leg 169 S), Saanich Inlet, were quantified. Sediments of this anoxic inlet in southern Vancouver Island, British Columbia consist of varved clays interbedded with slightly coarser massive layers. The 25 species of benthic foraminifera found were predominantly shallow water, calcareous forms, although a few planktic foraminifera and rare arcellaceans, as well as deeper water dysoxic benthic forms were also recorded. Most samples contained an impoverished fauna (average of 25 to 30 individuals), but massive layers contained statistically higher numbers and diversity of foraminifera than varves. A high proportion (> 50 %) of the foraminiferal fauna in the massive units were also found to be either damaged or broken. Such a high proportion of broken/damaged foraminifera along with the presence of arcellaceans in the massive layers lend credence to the hypothesis that they were transported from well oxygenated shallower, and nearshore parts of the inlet and deposited on the anoxic bottom of Saanich Inlet during subaqueous debris flows. Subaqueous debris flows in the inlet are induced by both seismic and non-siesmic events. The varved sediments also contain broken specimens of foraminifera. Although intact benthic foraminifera within the varves are typical forms capable of withstanding dysoxic conditions and appear to be autochthonous, broken specimens are mostly shallow water types requiring higher levels of oxygen. They are transported to the deeper anoxic parts of the inlet during spring freshet along with mineral rich silt. It is difficult to distinguish between seismic and non-seismic debris flows as few recorded earthquakes in the region have been conclusively linked with massive layers.

Wright, C.A., Dallimore, A., Thomson, R.E., Patterson, R.T., Ware, D. 2005. 聽 Late Holocene paleofish populations in Effingham Inlet, British Columbia, Canada. Palaeogeography, Palaeoclimatology, Palaeoecology: 224 (4): 367-384.聽https://doi.org/10.1016/j.palaeo.2005.03.04

Paleontological studies of fish remains in laminated sediments provide a proxy relationship between fish populations and ocean climate. This study examines climate variability from approximately 500 y B.P. to 4000 y B.P. as recorded in fish remain abundances (primarily scales) collected from laminated sediments within Effingham Inlet on the west coast of Vancouver Island, British Columbia. The study also discusses technical issues involving fish remains from laminated sediments, including sampling resolution, sediment volume, identification of remains and appropriate abundance considerations.

The dominant species in the assemblage include Northern anchovy and Pacific herring, with lesser percentage-abundances from rockfish, hake, elasmobranches and surfperch. The data indicate that Northern anchovy experienced a shift in scale deposition abundance at approximately 2800 y B.P. with not only a greater total abundance but also a greater consistency of deposition with time. Pacific herring underwent cyclical deposition that changed little through time. Statistical analysis reveals that none of these species is directly responding to climatic signals as indicated in the lithological and palynological record, but that this could have been partially due to the sampling resolution of the piston core. Analysis indicates a lack of correlation between the two dominant species, as might be expected on the basis of their opposing lifestyle strategies with respect to sea surface temperatures.

With appropriate sampling strategies, paleohistorical fish remains from laminated sediments reflect changes in population structure and behaviour for some species, illustrate basic secondary trophic information, and provide potential clues to basinscale oceanographic/climatological variability.

Boudreau, R.E., Galloway, J., Patterson, R.T., Kumar, A., Frederick A. Michel, F.A. 2005. A paleolimnologic record of Holocene climate and environmental change in the Temagami region, notheastern Ontario. Journal of Paleolimnology 33 (4): 445-461.聽https://doi.org/10.1007/s10933-004-7616-7

The Arcellacean (Thecamoebian) fauna was assessed in five Holocene sediment cores obtained from James and Granite lakes in the Temagami region of northeastern Ontario. In addition, palynological analysis was carried out on two of these cores, one each from James and Granite lakes. The first indication of postglacial colonization by plants was the appearance of rare Cupressaceae pollen, dated to 10,800 yr BP. Plant diversity began to increase by 10,770 yr BP when Pinus spp. and Larix migrated into the area. The first appearance of arcellaceans occurred after 9650 yr BP in assemblages dominated by Centropyxis constricta and opportunistic Centropyxis aculeata. High abundances of charophytes in the cores until 8800 yr BP indicated that macroalgae were proliferating at this time. This deposition is interpreted to have occurred during the draining of an ice-marginal lake following the retreat of the Laurentide Ice Sheet. Based on pollen analysis, warmer conditions associated with the Holocene Hypsithermal prevailed in the area from 6250 to 4115 yr BP. The stable, open Great Lakes 鈥� St. Lawrence type forest that developed here at the beginning of the Hypsithermal continues to prevail to the present. The periodic colonization of the lake by beavers (Castor canadensis) acted as a control on water-level and eutrophication through the Holocene. Evidence of eutrophication was indicated in the core samples by the abundance of high levels of the alga Pediastrum and the arcellacean Cucurbitella tricuspis. Eutrophication periodically developed when beavers dammed a site, causing the rate of flow in drainage streams to slow and stagnant conditions occurred. When the site became depleted of the nearby trees, which were preferred by beaver (Betula, Alnus and Populus), the dam would be abandoned, causing the water-level to drop. Stagnant conditions were reduced as flow levels increased, reducing eutrophication and resulting in recovering forest stands. In addition, the lowering water levels would result in encroachment of the forest along the lake shore. This cycle occurred many times in the history of this lake as indicated by fluctuations in the size of arcellacean populations.

Chang, A.S., Patterson, R.T. 2005. Climate shift at 4400 years BP: Evidence from high-resolution diatom stratigraphy, Effingham Inlet, British Columbia, Canada. Palaeogeography, Palaeclimatology, Palaeoecology 226: 72-92.

Diatom paleoecology and climatic interpretations were assessed from a 15-cm long laminated sediment slab extracted from an anoxic fjord in southwest British Columbia. The slab spans at least 62 years of deposition, determined from counting varves, and is dated at approximately 4400 years BP. The slab shows a sedimentation pattern where thick diatom-rich varves at the bottom become thinner and more silty toward the top. Thin section analysis reveals that the thicker varves contain a distinct succession of diatoms, representing seasonal deposition throughout each year. Annual-scale subsampling shows that the abundance of coastal marine diatoms, namely a weakly silicified form of Skeletonema costatum, decreased over the 62-year period, while benthic and brackish water diatoms, such as Planothidium delicatulum and Achnanthes minutissima, increased with the concomitant increase in silt. The increase in such benthic species and silt, along with the presence of ~1 cm thick nonlaminated intervals, is interpreted to represent deposition during progressively increasing precipitation over time. These
sedimentation patterns and changes in diatom assemblages may signify a change in the relative intensities of the Aleutian Low (AL) and North Pacific High (NPH) atmospheric pressure systems. Thicker diatomaceous varves at the bottom of the slab reflect a stronger NPH system with associated coastal upwelling and enhanced diatom production. The thinner silty varves at the top of the slab suggest that the AL system was prevalent, resulting in greater amounts of precipitation and reduced upwelling. The findings of this study show that significant natural environmental change can occur within a twenty-year time frame, and can provide a basis for the study of modern change in the ocean 鈥� atmosphere system over the northeast Pacific Ocean.

Patterson, R.T., Prokoph, A., Kumar, A., Chang, A.S., Roe, H.M. 2005. Holocene variability in pelagic fish and phytoplankton productivity along the west coast of Vancouver Island, NE Pacific Ocean. 聽 Marine Micropaleontology 55 (3,4): 183-204. 聽https://doi.org/10.1016/j.marmicro.2005.02.006

Fish stocks and dinoflagellates are essential components of the marine food chain. Sediment cores from a predominantly anoxic basin in Effingham Inlet, Vancouver Island, British Columbia, archive a late Holocene (~500鈥�5300 years BP) record of paleoproductivity in the North American Coastal Upwelling Domain (CUD). We present evidence that late Holocene changes in the dinoflagellate cyst assemblages, sedimentary record, and fish stocks in the northeastern Pacific Ocean fluctuated, at least partially, in accordance with regional and global climate cycles. Principal components analysis (PCA), and trend, wavelet and spectral analyses were used to identify relationships, cycles and trends in sediment grey-scale values, and the abundances of fish scales and dinoflagellate cysts on centennial to millennial time scales. Most observed cycles fluctuated in intensity over time, particularly following transition of the regional climate to a higher rainfall phase that impacted coastal oceanic dynamics ~3400F150 years ago. Correlation of the marine paleoproductivity records observed in Effingham Inlet with solar influenced climate proxy cycles observed in the North Atlantic region indicates that solar forcing at different scales might have influenced the climate in the northeast Pacific as well. In particular an 1100- to 1400-year cycle in regional climate is well represented in the fish productivity proxy and sedimentological record. It was also observed that colder water, high- productivity, Selenopemphix nephroides and anchovydominated 鈥楢nchovy Regime鈥� ecosystems alternate with warmer water, herring- dominated 鈥楬erring Regime鈥� ecosystems at millennial time scales. The fish scale record preserved in Effingham Inlet indicates that the NE Pacific is now in transition from an 鈥榓nchovy鈥� to a 鈥榟erring鈥� dominated regime.

Patterson, R.T., Dalby, A.P., Roe, H.M., Guilbault, J.-P., Hutchinson, I., Clague, J.J. 2005. Relative utility of foraminifera, diatoms and macrophytes as high resolution indicators of paleo-sea level.聽Quaternary coastal morphology and sea-level changes.聽Quaternary Science Reviews 24 (18, 19): 2002-2014.聽https://doi.org/10.1016/j.quascirev.2004.11.013

A multiproxy analysis was carried out on diatom, foraminiferal and macrophyte assemblages across the saltmarsh at Zeballos, Vancouver Island, British Columbia. To determine which group, or combination of groups provided the most accurate elevational zonations, 36 stepwise multiple linear regressions (SMLR) were carried out using a variety of data transformations on an elevational training set. Adjusted R2 values yielded statistically significant results in all analyses as follows: foraminifera (0.658鈥�0.870); diatoms (0.888鈥�0.974); macrophytes (0.671鈥�0.844); foraminifera/diatoms (0.941鈥�0.981); foraminifera/ diatoms/ macrophytes (0.958鈥�0.993). The most realistic SMLR results were obtained when data transformations comprised of (ln) normalized fractional abundance data was carried out on species present in statistically significant numbers (NrfaEQ). Of the individual proxies assessed, diatoms yielded the most significant adjusted R2 results, with the low marsh diatom Achnanthes hauckiana beingone of the most important predictor variables (pv鈥檚). Amongst the foraminifera, the low marsh species Miliammina fusca and high marsh Balticammina pseudomacrescens were determined to be the most significant pv鈥檚. For macrophytes, the low marsh species Carex lyngbyei, the high marsh species Juncus balticus, Shannon鈥揥iener Diversity Index (SDI) and absence of plant cover on the tidal flat were the most important pv鈥檚. As SMLR analysis of all individual groups and combinations of groups yielded statistically significant results, the choice of proxies, or combinations of proxies that are suitable for paleo-sea level research is at the discretion of the researcher.