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51.
Hermann Behling 《Vegetation History and Archaeobotany》1996,5(3):241-246
Palynological studies on late Quaternary lake sediments from the region of the Amazon estuary, 100 km north-east of Belém, Pará State, Brazil, enable reconstruction of lowland Amazonian rain forest during the Late-glacial and Holocene periods. Late-glacial forests included populations of Podocarpus which suggests a distinct climatic cooling. Ilex was abundant in the early Holocene. Records of the mangrove taxon, Rhizophora, indicate rapid Atlantic sea-level rise in the beginning of the Holocene. High charcoal representation may reflect the first arrival of Amerindians in the Amazon coastal area, probably about 10 800 B.P. 相似文献
52.
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54.
J. E. Bradshaw H. E. Stewart R. L. Wastie M. F. B. Dale M. S. Phillips 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1995,90(6):899-905
A diallel set of crosses, including selfs and some reciprocal crosses, was made between 15 parents chosen for their male fertility from those included in a tetraploid potato (Solanum tuberosum subsp. tuberosum) breeding programme at the Scottish Crop Research Institute. Seedling progeny tests were used to evaluate the progenies for non-race-specific resistance to late blight (Phytophthora infestans) in both foliage and tubers, quantitative resistance to the white potato cystnematode (PCN) (Globodera pallida) and the commercial worth of their tubers as judged by breeders' visual preference. No reciprocal differences were found. Comparisons of the selfs and crosses revealed inbreeding depression for breeders' preference, which varied among the parents from negligible to severe, whilst there were also statistically significant differences for foliage and tuber blight, but not for PCN. When the selfs were omitted from the combining ability analyses, large differences in general combining ability (GCA) were found for all four traits, and smaller differences in specific combining ability for tuber blight and breeders' preference. The only statistically significant correlation between GCAs for different traits was a favourable one of r = 0.56 between foliage and tuber resistance to late blight. It was concluded that prospects were good for simultaneously improving all four traits by multitrait genotypic recurrent selection. 相似文献
55.
C. Brombacher 《Vegetation History and Archaeobotany》1997,6(3):167-186
This paper describes the results of the archaeobotanical examination of four Late Neolithic lakeshore settlements on Lake
Biel in Switzerland. Due to the excellent preservation conditions in lakeshore settlements, non-carbonized as well as carbonized
seeds and fruits were recovered in large numbers. In addition to the diaspore analyses, some samples of charcoal and moss
were identified. The spectrum of cultivated plants was markedly different between the sites. In the transition from the 34th
to 33rd century B.C. (sites Nidau, Lüscherz and Lattrigen ‘VI’) naked wheat and barley were predominant, while in the 32nd
century B.C. (Lattrigen'VII') emmer (a glume wheat) was most abundant. Flax and opium poppy were of great importance during
the whole late Neolithic period. In addition to cereals, a large number of cereal weeds were detected. The wild flora included
a high percentage of aquatic and lake-shore plants which results from the strong influence of water on the cultural layers.
Taxa of flood-plain forest are also common. The proportion of potential grassland plants was low (in total only 13 taxa) which
suggests that in addition to the cultivated fields only few pastures and grassland areas existed close to the settlements. 相似文献
56.
中国中生代晚期蛇蛉化石研究(蛇蛉目:巴依萨蛇蛉科,中蛇蛉科,异蛇蛉科) 总被引:10,自引:1,他引:9
本文根据最新采获的保存完好的蛇蛉化石,对中国古生代晚期蛇蛉化石巴依萨蛇蛉科,中蛇蛉科和异蛇蛉科的有关属种的构造特征,分类位置和异我进行新的补充和厘定,建立4个新属:野蛇蛉属Rudiraphidia gen。nov,小蛇蛉属Mioraphidia gen。nov。普蛇蛉属Xynoraphidia gen。nov。丽蛇蛉属Caloraphidia gen,nov;7个新种;美脉巴依萨蛇蛉Baissop 相似文献
57.
记述了丹江库区周围发现的三种兔形类化石:产在丹江二级阶地基座岩层中的淅川跳兔(新种)Alloptoxxichuanwnsissp.nov.个体小,形态较早中新世中期的A.minor原始,其时代可能是早中新世早期,同时详细讨论了Alloptox的进化和分类;发现于台子山林场裂隙堆积物中的进步上新五褶兔(新种)Pliopentalagusprogressivussp.nov.个体为该属已知各种中最大者,形态较已知种更接近于现生的Pentalagus,它的时代可能为上新世末或更新世初;产于郧县曲远河口汉水Ⅳ级阶地的复齿拟鼠兔Ochotonoidescomplicidens与蓝田金丝猴发现于同一阶地,推测其时代为早更新世晚期。 相似文献
58.
贵州盘县大洞更新世灵长类化石 总被引:2,自引:1,他引:1
本文记述贵州盘县大洞中-晚更新世洞穴堆积中的猴类化石,数量不多,被归入短尾猴(Macacaarctoides),熊猴(M.cf.assamensis)和疣猴亚科(Colobinae)本研究为南方洞穴堆积单个灵长类牙齿的鉴定积累一些资料,同时也扩大了贵州省猴类化石的分布。 相似文献
59.
Sabine Karg 《Vegetation History and Archaeobotany》1995,4(1):41-50
Weed assemblages from late medieval cornfields have been studied for the first time in northern Switzerland. Eleven samples from at least two different grain stores were investigated. The samples were collected from the carbonised remains of six wooden houses built in the late 13th century A.D. and which burnt down in the middle of the 15th century. The weed floras found in the spelt (Triticum spelta) and oats (Avena sativa) indicate a high botanical diversity in the cornfields at harvest time. Although oats are normally a summer crop and spelt a winter crop, both summer and winter crop weeds (as well as many different present-day grassland taxa) were found in each type of grain. Most of the weeds found were perennial plants, which was interpreted as an indication of both extensive tillage of the arable land and application of the three-field rotation system (Dreifelderwirtschaft). The spectra of the two palaeophytocoenoses (assemblages of ancient plant remains) studied suggest that the phytosociological method may not be reliable for classification of the late medieval remains into summer and winter crop weed communities. These findings should provide a better understanding of the development of anthropogenic plant communities, and in particular, the development of crop weed communities. 相似文献
60.
Isabel Figueiral 《Vegetation History and Archaeobotany》1995,4(2):93-100
Vegetation and environmental change from late Bronze Age to the Roman period in north-west Portugal is reconstructed on the basis of charcoal analyses. The site was occupied by people of the Castrejo culture, i.e. an Iron Age culture that developed in the north-west Iberian peninsula. The pattern of exploitation of natural wood resources by local populations during this period appears to be similar during the three phases of occupation. The frequencies of light-demanding plant species, mostly Leguminosae, testify to considerable destruction and degeneration of the climax woodlands. The preference of particular wood for specific uses, such as roofing, is discussed and the Holocene history of selected trees within the wider region is considered. 相似文献