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1.
Plant microfossil analysis was carried out on 12 soil samples from a variety of landscape features at three locations (100–250 m a.s.l.) along a 950 m transect at Te Niu, Easter Island. Pollen and phytolith assemblages were dominated by palms and ground ferns, and suggested disturbed forest. We identified pollen of bottle gourd (Lagenaria siceraria) and starch grains of the common yam (Dioscorea alata), sweet potato (Ipomoea batatas) and taro (Colocasia esculenta). The data suggest a mixed-crop, dryland production system at Te Niu dominated by yam and sweet potato, and supplemented by taro and bottle gourd. The data provide direct evidence of crop type and range, supporting the indirect evidence (topographic and landscape features, field and historical research, comparisons with elsewhere in the Pacific) that much of the rock covered landscape of Easter Island was used for intensive horticulture.  相似文献   
2.
Chuaria is widespread in Late Precambrian deposits throughout the world. In China it has been found in the Jingeryu Formation of Jixian County, Tianjin, and in its equivalents in eastern China including the Nanfen Formation of Liaoning and Jilin Provinces, and the Liulaobei Formation of Anhui Province. In the latter, Chuaria is associated with the genus Tawuia which Hofmann (in Hofmann & Aitken, 1979) described as algae of undertermined affinity and which is based on material from Canada. The glauconitic sandstone directly resting upon Chuaria-bearing greyish-green shale of the Jingeryu Formation in Jixian County has a K-Ar age of 0.899 Ga. This paper describes C. circularis Walcott, T. dalensis Hofmann and T. sinensis n. sp., and discusses the morphology, biological and taxonomic affinities, and age and geographic distribution of Chuaria. Because of the association of Chuaria and Tawuia in the Mackenzie Mountains, Canada, and also in the area of Shouxian County, Anhui Province, China, it is considered that Chuaria and Tawuia probably have close affinities. According to their general morphology and occurrence, both may be marine planktonic multicellular algae.  相似文献   
3.
Dietary reconstructions based on plant microfossils, such as starch grains and phytoliths, have been useful in increasing our understanding of past human populations. Microfossils have been recovered from sediments, stone tools, and, more recently, dental calculus. Methods for recovering microfossils from dental calculus have yet to be firmly established and there is some question about potential damage to the teeth. Using a sample of teeth from the middle Holocene site of Tell al-Raqā'i, Syria, we tested using a dental pick to sample the calculus. ESEM images taken before and after sampling show no damage to the enamel surface, and examination of the recovered microfossils show that this method provides ample material for study, even when not all of the calculus is removed from the tooth. Preliminary identification of the plant microfossils suggests that these individuals were consuming a variety of plant foods, but that domesticated cereals such as wheat and barley made up a surprisingly small portion of their diet.  相似文献   
4.
Sites which have been occupied semi-continuously in the past present some inherent difficulties for archaeology. Here we present new research from a coastal site on the North Island of New Zealand at Cooks Beach where anthropogenic vegetation changes are seen using microfossil analysis of obsidian tools, sediments and pit fill. The results indicate the initial presence of people in AD 1300–1400 followed by subsequent periods of disuse or abandonment and sweet potato (Ipomoea batatas) cultivation. Around the time of initial settlement, obsidian from this location is found at sites across the country. After AD 1400 the area appears to be deserted for a century or more, after which we see evidence for the cultivation of sweet potato in AD 1500 as evidenced by extensive soil modification and numerous storage pits. There is no evidence of a permanent settlement at the site. The geographic distribution of Cooks Beach obsidian was constricted while the site was used for sweet potato cultivation, a pattern often attributed to increased warfare. It appears cultivation was abandoned after AD 1650 marking a second secession of use, a fact confirmed in AD 1769 when Captain Cook visited the area. We consider the possible drivers for the late abandonment of cultivation at Cooks Beach.  相似文献   
5.
Analysis of plant microfossils (pollen, phytoliths, starch grains and xylem cells) was carried out on 12 soil samples from a variety of pre-contact archaeological features in South Kona within a portion of what has been termed the Kona Field System, on the Island of Hawaii. The oldest radiocarbon ages of the sampled deposits are 1300–1625 AD and 1310–1470 AD. The pollen and phytolith evidence suggests a change from more to less trees and shrubs in the area as a result of human activity. We found phytoliths of banana (Musa sp.) leaves in most and starch grains and xylem cells of tuberous roots of c.f. sweet potato (Ipomoea batatas) in all of the samples, suggesting that the sampled features were associated with these crops and that both crops were cultivated intensively within the study area. Higher concentrations (volumetric) of starch and xylem in samples from older deposits suggest that cultivation was more intensive then. The apparent absence of starch and xylem remains of other tuberous crops archaeologically identified elsewhere in Polynesia suggests that tuberous cropping within the study area was mono-specific.  相似文献   
6.
Plant microfossil analysis was carried out on anthropogenic deposits from Yuku rock shelter, possibly occupied from before 14,200 cal. BP to recent times, in the Papua New Guinea Highlands. Elaeocarpus pollen has extremely high percentages throughout. Starch residues of lesser yam (Dioscorea esculenta) and one or more, undifferentiated Dioscorea species were identified, suggesting processing of these taxa since first use of the site. The latter include Dioscorea alata, Dioscorea bulbifera, Dioscorea nummularia and Dioscorea pentaphylla. Pollen and phytoliths of banana (Musa) appear 5200 cal. BP. We cannot differentiate between naturally growing and cultivated yams and bananas. Putative truffle (hypogeous Ascomycotina) spores in the deposits suggest foraging of truffles.  相似文献   
7.
Holocene relative sea-level (RSL) changes are described for the Isle of Skye, based upon evidence from isolation basins and back barrier environments. RSL rose across low-lying coastal areas in the early Holocene, inundating isolation basins in the Sleat peninsula, and then fell back in the early-middle Holocene before a fluctuating rise occurred later in the middle and late Holocene. A short-lived marine inundation at one site may have been caused by an episode of rapid RSL rise after the discharge of Lakes Agassiz–Ojibway in North America and/or the Holocene Storegga Slide tsunami, generated by submarine landsliding off South-West Norway. The empirical evidence for RSL change on Skye is compared with a recent shoreline-based glacio-isostatic adjustment model, which includes Skye, showing altitudes for the Holocene Storegga Slide tsunami, Main Postglacial, Blairdrummond and Wigtown shorelines in the area. The empirical evidence is shown to be in accord with the altitudes predicted by the model.  相似文献   
8.
The phytolith record from archaeological strata is a powerful tool for reconstructing aspects of past human behaviour and ecology. Considerable insights into the problems and potentials of this record can be obtained by studying phytoliths in modern plants. We prepared a phytolith reference collection of modern plants mostly from northern Greece that includes quantitative information on phytolith concentrations (number of phytoliths per gram dry organic material) and morphological assemblages. Here we analyse this reference collection with the aim of evaluating the strengths and weaknesses of the archaeological phytolith record. The reference collection comprises 62 different plant taxa. Of them, 28 are trees, 1 conifer, 10 shrubs and 1 herb, 3 domesticated annual legumes and 19 monocotyledons. We demonstrate quantitatively the extent to which woody species, legumes and fruits of dicots contribute only small amounts of phytoliths to the sediments per unit tissue dry weight, while leaves of trees and shrubs produce significant amounts of phytoliths and grasses are prolific phytolith producers. We compare the data of this reference collection with a similar reference collection from another Mediterranean ecosystem (Israel). The comparison indicates that some aspects of phytolith production are probably genetically controlled, whereas others are environmentally controlled. We note that despite the fact that woody species produce few phytoliths per gram of tissue, their record can be most informative when taking into account other properties of the sediments. We also note that jigsaw puzzle-shaped phytoliths normally form in plants that grow in humid conditions, but may form in arid environments when the plants are irrigated. This study clearly shows the extent to which some plants can be under-represented and others over-represented in the phytolith record. Knowing the extent of this bias can greatly improve our interpretation of the phytolith record.  相似文献   
9.
Early to Late Devonian (Emsian to late Famennian) organic walled microfossils were recovered from nineteen localities throughout the Tamworth Belt, northern New South Wales. The microfossil assemblages included poorly preserved chitinozoans and scolecodonts, spores and moderately well preserved foraminiferal linings. Fourteen species of foraminiferal linings from six genera are documented. At least three species of foramininferal linings (Inauris tubulata, Saccammina mea and Thurammina pustulosa) show potential for global correlation. Saccammina sp. cf. S. ampullacea and Thurammina mirrka may have application for correlation within Australia.  相似文献   
10.
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