气候变化领域集成服务门户(CCPortal): Reconstruction of 7500 years of coastal environmental change impacting seagrass ecosystem dynamics in Oyster Harbour (SW Australia)

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DOI	10.1016/j.palaeo.2020.109953
	Reconstruction of 7500 years of coastal environmental change impacting seagrass ecosystem dynamics in Oyster Harbour (SW Australia)
	Kaal J.; Lavery P.S.; Martínez Cortizas A.; López-Costas O.; Buchaca T.; Salinas C.; Serrano O.
发表日期	2020
ISSN	0031-0182
卷号	558
英文摘要	Seagrass ecosystems, which have important functions such as coastal protection and blue carbon sequestration, are threatened by anthropogenic pressure including climate change. Long-term data series from seagrass sedimentary archives (mats) can be used to understand natural cycles of environmental change and answer key questions related to contemporary management. A 7500 yr sediment record from Posidonia australis meadows in Oyster Harbour (Albany, SW Australia) was subjected to multiproxy reconstruction by means of pigment analysis (UHPLC), analytical pyrolysis (Py-GC–MS), carbonate content, δ13C and δ15N stable isotope ratios, organic C (Corg) content, Corg/N ratio and glomalin-related soil proteins (GRSP). The study revealed a brackish lagoon (7500–7000 cal yr BP) that was transformed in an open marine environment (7000–4100 cal yr BP) due to Holocene transgression. Earliest evidence of seagrass establishment was detected around 4500 cal yr BP, and meadow extension accelerated between 4100 and 3700 cal yr BP. The meadow environment was surprisingly resistant against environmental perturbations, as the mat, composed of P. australis seagrass fibres embedded within a siliciclastic mineral matrix containing biogenic carbonates, continued to develop steadily until 190 cal yr BP (1830 CE). Then, shifts in several proxies (pigments, GRSP) showed evidence of terrestrial runoff-triggered eutrophication/turbidity (likely driven by forest clearance and agricultural activities after European settlement), but the seagrass showed resilience (no decline of the proportion of seagrass-derived Corg). By contrast, since ~1930 CE seagrass retreat is evident in the biogeochemical record: lighter δ13C values, lower lignin abundance and shifts in pigment abundance and types, affecting the balance between seagrass inputs and alternative sources, as was observed in previous studies of the area. The findings show that pigment proxies are useful early indicators of shifts in seagrass ecosystem condition, while lignocellulose and other pyrolysis products are useful proxies of more profound ecosystem alterations that influence seagrass abundance. The record indicates that the climax seagrass ecosystem condition, which prevailed for several millennia, had been impacted over the last century. Management of seagrass and coastal ecosystems should aim to avoid crossing ecological thresholds and diminish local impacts aggravating those of global change. © 2020 Elsevier B.V.
英文关键词	Blue carbon; Coastal ecosystem; Molecular characterization; Palaeo-ecology; Posidonia australis
语种	英语
scopus关键词	anthropogenic effect; biochemistry; carbon sequestration; cellulose; climate variation; coastal protection; coastal zone; ecosystem dynamics; environmental change; environmental impact; eutrophication; marine environment; meadow; pigment; proxy climate record; pyrolysis; reconstruction; seagrass; siliciclastic deposit; transgression; turbidity; Australia; Oyster Harbour; Western Australia; Ostreidae; Posidonia australis
来源期刊	Palaeogeography, Palaeoclimatology, Palaeoecology
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/150345
作者单位	Pyrolyscience, Madrid, Spain; School of Science, Centre for Marine Ecosystems Research, Edith Cowan University, 270 Joondalup Drive, Joondalup, WA 6027, Australia; EcoPast, Departamento de Edafoloxía e Química Agrícola, Universidade de Santiago de Compostela, Santiago de Compostela, Spain; Archaeological Research Laboratory, Department of Archaeology and Classical Studies, Stockholm University, Wallenberglaboratoriet, Stockholm, SE-106 91, Sweden; Centro de Estudios Avanzados de Blanes, Consejo Superior de Investigaciones Cientificas, Blanes, 17300, Spain
推荐引用方式 GB/T 7714	Kaal J.,Lavery P.S.,Martínez Cortizas A.,et al. Reconstruction of 7500 years of coastal environmental change impacting seagrass ecosystem dynamics in Oyster Harbour (SW Australia)[J],2020,558.
APA	Kaal J..,Lavery P.S..,Martínez Cortizas A..,López-Costas O..,Buchaca T..,...&Serrano O..(2020).Reconstruction of 7500 years of coastal environmental change impacting seagrass ecosystem dynamics in Oyster Harbour (SW Australia).Palaeogeography, Palaeoclimatology, Palaeoecology,558.
MLA	Kaal J.,et al."Reconstruction of 7500 years of coastal environmental change impacting seagrass ecosystem dynamics in Oyster Harbour (SW Australia)".Palaeogeography, Palaeoclimatology, Palaeoecology 558(2020).