The effect of the introduction of livestock on the erosion of alpine soils: a comparison of five dating techniques applied to sediments of the Australian alpine Blue Lake.

IF 1.7 3区 地球科学 Q4 ENVIRONMENTAL SCIENCES
Patrick De Deckker, Gary J Hancock, Jon M Olley, Shawn Stanley, Geoffrey Hope
{"title":"The effect of the introduction of livestock on the erosion of alpine soils: a comparison of five dating techniques applied to sediments of the Australian alpine Blue Lake.","authors":"Patrick De Deckker,&nbsp;Gary J Hancock,&nbsp;Jon M Olley,&nbsp;Shawn Stanley,&nbsp;Geoffrey Hope","doi":"10.1007/s10933-023-00284-x","DOIUrl":null,"url":null,"abstract":"<p><p><sup>210</sup>Pb and <sup>137</sup>Cs dating of bulk sediments obtained from the alpine Blue Lake, located in the Snowy Mountains of southeastern Australia, was applied here to date recent lacustrine sediments. In addition, the presence of <i>Pinus</i> pollen (a taxon introduced in Australia about 150 years ago) down to a sediment depth of 56 cm in the core is used to obtain a chronology for the upper part of the core. Accelerated Mass Spectrometry radiocarbon dates obtained from organic muds from the same core do not agree with the chronology constructed using the three other dating techniques. In addition, optically stimulated luminescence (OSL) dating of single quartz grains, from sediment-core samples collected from the same lake, was applied to date recent lacustrine sediments. The optical age of 185 ± 20 years for a sample at 60-62 cm depth, and 470 ± 50 years at 116-118 cm depth are well over 1000 years younger than the ages inferred from radiocarbon dates. We therefore infer that the 'old' radiocarbon ages result from carbon stored for considerable time within the catchment prior to its transport and deposition on the lake floor. As plant decomposition occurs at much slower rates in high altitude environments, these results bring into question the veracity of previously published radiocarbon dates from Blue Lake and alpine lake sediments in general. The deposition ages inferred from the <sup>210</sup>Pb-<sup>137</sup>Cs and OSL dating, and the first appearance of <i>Pinus</i> pollen, indicate that for the 100-year period after European settlement (from the mid 1800s to early 1900s) the sediment-accumulation rate increased by a factor of about 2, from 0.19 ± 0.01 cm yr<sup>-1</sup> to 0.35 ± 0.02 cm yr<sup>-1</sup>. In the 1900s the accumulation rate increased further to 0.60 cm yr<sup>-1</sup>. The accumulation rate was particularly rapid in the 20-year period from 1940-1960, reaching a rate 18 times higher than the pre-European rate in the mid-1950s. The increase in sedimentation rate is attributed to changes in land use resulting from European activities in the lake catchment, primarily through sheep and cattle grazing in the Blue Lake catchment.</p>","PeriodicalId":16658,"journal":{"name":"Journal of Paleolimnology","volume":null,"pages":null},"PeriodicalIF":1.7000,"publicationDate":"2023-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10164618/pdf/","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Paleolimnology","FirstCategoryId":"89","ListUrlMain":"https://doi.org/10.1007/s10933-023-00284-x","RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q4","JCRName":"ENVIRONMENTAL SCIENCES","Score":null,"Total":0}
引用次数: 0

Abstract

210Pb and 137Cs dating of bulk sediments obtained from the alpine Blue Lake, located in the Snowy Mountains of southeastern Australia, was applied here to date recent lacustrine sediments. In addition, the presence of Pinus pollen (a taxon introduced in Australia about 150 years ago) down to a sediment depth of 56 cm in the core is used to obtain a chronology for the upper part of the core. Accelerated Mass Spectrometry radiocarbon dates obtained from organic muds from the same core do not agree with the chronology constructed using the three other dating techniques. In addition, optically stimulated luminescence (OSL) dating of single quartz grains, from sediment-core samples collected from the same lake, was applied to date recent lacustrine sediments. The optical age of 185 ± 20 years for a sample at 60-62 cm depth, and 470 ± 50 years at 116-118 cm depth are well over 1000 years younger than the ages inferred from radiocarbon dates. We therefore infer that the 'old' radiocarbon ages result from carbon stored for considerable time within the catchment prior to its transport and deposition on the lake floor. As plant decomposition occurs at much slower rates in high altitude environments, these results bring into question the veracity of previously published radiocarbon dates from Blue Lake and alpine lake sediments in general. The deposition ages inferred from the 210Pb-137Cs and OSL dating, and the first appearance of Pinus pollen, indicate that for the 100-year period after European settlement (from the mid 1800s to early 1900s) the sediment-accumulation rate increased by a factor of about 2, from 0.19 ± 0.01 cm yr-1 to 0.35 ± 0.02 cm yr-1. In the 1900s the accumulation rate increased further to 0.60 cm yr-1. The accumulation rate was particularly rapid in the 20-year period from 1940-1960, reaching a rate 18 times higher than the pre-European rate in the mid-1950s. The increase in sedimentation rate is attributed to changes in land use resulting from European activities in the lake catchment, primarily through sheep and cattle grazing in the Blue Lake catchment.

Abstract Image

Abstract Image

Abstract Image

引入牲畜对高山土壤侵蚀的影响:应用于澳大利亚高山蓝湖沉积物的五种测年技术的比较。
本文对澳大利亚东南部雪山高山蓝湖的大量沉积物进行了210Pb和137Cs测年,以确定近期湖泊沉积物的年代。此外,在岩芯中沉积深度达56厘米的松花粉(一种约150年前引入澳大利亚的分类单元)的存在被用来获得岩芯上部的年表。从同一岩芯的有机泥浆中获得的加速质谱放射性碳年代测定与使用其他三种年代测定技术构建的年代测定不一致。此外,从同一湖泊采集的沉积物岩芯样本中,对单个石英颗粒进行了光激发光(OSL)测年,并将其应用于最近的湖泊沉积物测年。185岁的光学年龄 ± 60-62厘米深度的样本为20年,470 ± 在116-118厘米深处的50年比根据放射性碳年代推断的年龄年轻1000多年。因此,我们推断,“旧”放射性碳年龄是由于碳在湖底运输和沉积之前在集水区内储存了相当长的时间。由于植物分解在高海拔环境中的速度要慢得多,这些结果使人们对之前公布的蓝湖和高山湖泊沉积物放射性碳年代的准确性产生了质疑。根据210Pb-137Cs和OSL测年推断的沉积年龄,以及松花粉的首次出现,表明在欧洲人定居后的100年期间(从19世纪中期到20世纪初),沉积物积累率从0.19增加了约2倍 ± 0.01 cm yr-1至0.35 ± 0.02厘米yr-1。在20世纪,积累率进一步增加到0.60厘米yr-1。在1940-1960年的20年期间,积累率特别快,比20世纪50年代中期的欧洲前增长率高出18倍。沉积率的增加归因于欧洲在湖泊流域的活动导致的土地利用变化,主要是通过在蓝湖流域放牧绵羊和牛。
本文章由计算机程序翻译,如有差异,请以英文原文为准。
求助全文
约1分钟内获得全文 求助全文
来源期刊
Journal of Paleolimnology
Journal of Paleolimnology 地学-地球科学综合
CiteScore
3.70
自引率
9.50%
发文量
44
审稿时长
3 months
期刊介绍: The realization that a historical perspective is often useful, if not essential, to the understanding of most limnological processes has resulted in the recent surge of interest in paleolimnology. The main aim of the Journal of Paleolimnology is the provision of a vehicle for the rapid dissemination of original scientific work dealing with the reconstruction of lake histories. Although the majority of papers deal with lakes, paleoenvironmental studies of river, wetland, peatland and estuary systems are also eligible for publication. The Journal of Paleolimnology, like the subject itself, is multidisciplinary in nature, and papers are published that are concerned with all aspects (e.g. biological, chemical, physical, geological, etc.) of the reconstruction and interpretation of lake histories. Both applied and more theoretical papers are equally encouraged. The Journal of Paleolimnology will continue to be a major repository for papers dealing with climatic change, as well as other pressing topics, such as global environmental change, lake acidification, eutrophication, long-term monitoring, and other aspects of lake ontogeny. Taxonomic and methodological papers are also acceptable provided they are of relatively broad interest. New equipment designs are frequently featured. In addition to original data and ideas, the Journal of Paleolimnology also publishes review articles, commentaries and program announcements. A relevant Book Review Section is also featured.
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
确定
请完成安全验证×
copy
已复制链接
快去分享给好友吧!
我知道了
右上角分享
点击右上角分享
0
联系我们:info@booksci.cn Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。 Copyright © 2023 布克学术 All rights reserved.
京ICP备2023020795号-1
ghs 京公网安备 11010802042870号
Book学术文献互助
Book学术文献互助群
群 号:481959085
Book学术官方微信