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81.
石门台自然保护区位于广东省中北部,面积82260hm^2,是全省面积最大的保护区。根据我们过去三年的初步调查和研究,石门台保护区共有藓类植物33科89属158种(含1亚种3变种),其中广东新记录属3属,分别是Eccremidium、Phyllodon和Stereodontopsis;另外,Eccremidium brisbanicum等23种为广东新记录种。  相似文献   
82.
Bryophytes are some of the most sensitive biological indicators of environmental change. Springs have a significant presence of bryophytes and so are ideal habitats for studying their relationship with the environment. We tested whether bryophyte assemblages can be explained with macro-, meso- and micro-ecological variables (i.e. seasonal climate, altitude, water pH and conductivity) sampling bryophytes from 198 semi-natural springs distributed along montane regions in the north-eastern Iberian Peninsula. We tested the influence of environmental variables on bryophyte assemblages in springs using sparse Partial Least Squares. Our results show that variability in bryophyte assemblages is explained by seasonal climate (temperature and precipitation from winter, spring, summer and autumn and temperature and precipitation seasonality), altitude and water conductivity. The results obtained by the present study will be useful for predicting bryophyte diversity in springs using simple and easy to obtain variables such as climate, water pH and conductivity.  相似文献   
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84.
As a result of the study of both recent collections and a review of herbarium specimens, the following taxa are reported for the first time from various Italian regions: Hedwigia stellata Hedenäs, Hedwigia ciliata var. leucophaea Bruch & Schimp., Pleurozium schreberi (Willd. ex Brid.) Mitt. and Ptychostomum compactum Hornsch. var. compactum. The last taxon is new for southern Italy, while the report of Pleurozium schreberi confirms the occurrence of this species in southern Italy after more than half a century. Moreover, Crossidium laxefilamentosum Frey & Kürschner represents the second report of this species from Italy.  相似文献   
85.
The occurrence on the Pollino massif (southern Italy) of several remarkable mosses, which are rare or very rare in Italy, is reported. They are Orthotrichum acuminatum H. Philib., Distichium inclinatum (Hedw.) Bruch & Schimp. and Grimmia longirostris Hook., new to the southern part of the Italian peninsula, and Schistidium dupretii (Thér.) W.A. Weber, new to South Italy. Moreover, Orthotrichum cupulatum Hoffm. ex Brid. var. fuscum (Venturi) Boulay, a very rare taxon in Europe and up to now considered vanished in Italy, is rediscovered in Italy after about one century from its single previous report.  相似文献   
86.
从1995~2009年,作者对新疆喀纳斯自然保护区藓类植物进行了全面的调查、采集、鉴定,分析研究。结果表明,该自然保护区藓类植物共有37科113属253种(含1变种),优势科主要体现寒、温带地区分布类型,该区藓类植物生境的多样性可以从物种多样性,如曲尾藓科、木灵藓科、泥炭藓科、紫萼藓科、丛藓科等的广泛分布反映出来。通过与该区相邻的6个地区的物种丰富度系数比较,该自然保护区综合系数S i排第三位,说明此区藓类植物物种多样性丰富,这与本区的水分条件有很大关系。藓类植物区系成分以北温带成分为绝对优势,占总种数的83.33%;东亚成分占总种数的5.10%;东亚-北美成分占总种数的4.17%,各区系成分交汇。主成分分析和聚类分析表明,喀纳斯自然保护区藓类植物区系与新疆东部天山、内蒙古大青山、吉林长白山、河北木兰围场藓类植物区系关系较接近,与贵州梵净山、云南鸡足山藓类植物区系关系疏远,体现了我国北方藓类植物分布特征。  相似文献   
87.
Well-preserved human bodies more than 2000 years old have been found in peat bogs derived mainly from sphagnum mosses. Preservation is correlated with the occurrence of -keto-carboxylate groups in a glycuronoglycan (‘sphagnan') that comprises 60% of the holocellulose in the hyaline cell walls of the mosses [Painter (1991b). Carbohydr. Polym., 15, 123–142]. There is now renewed interest in other biodegradable materials that have been found preserved in peat, including carcasses of domestic animals, loaves of bread, dried fruits, berries, and kegs of butter or cheese up to 1800 years old. This review attempts to correlate these examples of fortuitous preservation in peat with other, more familiar methods of food preservation that depend in the first instance upon the condensation of highly reactive carbonyl compounds with primary amino-groups or ammonia. The Maillard reaction inhibits microbial growth by sequestering ammonia, aminoacids and peptides, while the brown, polymeric end-products (‘melanoidins') inhibit by cross-linking polypeptide chains and sequestering essential, multivalent metal cations. These reactions could find broader or entirely new applications in food preservation.  相似文献   
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89.
This overview presents a historical summary of the past collectors of bryophytes (mosses, liverworts and hornworts) in Sri Lanka, formerly Ceylon, and some of the researchers who studied and published the results of their explorations. The first British collectors of the early nineteenth century were linked with the development of the Botanic Garden and herbarium in Peradeniya, of which George Gardner and George Thwaites made the greatest contributions, resulting in three publications by William Mitten on both mosses and liverworts. By the mid-nineteenth century, collectors from other countries took the lead, firstly Johannes Nietner from Germany and Odoardo Beccari from Italy. By the early twentieth century, Victor Schiffner from Austria and Max Fleischer from Germany became the leading bryologists throughout SE Asia, and both visited Ceylon. Fleischer’s work was part of a monographic revision of all mosses resulting in many new genera and species. After Fleischer, the most important bryologist was the German Theodor Herzog, who was the first to describe the ecological structure and bryological richness of different forest zones in southern Ceylon, with insight into forest loss from agricultural and population expansion, and a summary of biogeographical links of the bryoflora. The English bryologist H.N. Dixon took over from Mitten in describing many new moss species. Since independence in 1948, bryology in Sri Lanka has had major input from some local bryologists, such as B.A. Abeywickrama, as well as several important visitors, notably H. Inoue from Japan, C.C. Townsend from England, P.P.M. Tixier from France, and Maurice Onraedt from Belgium. Awareness in Sri Lanka of the need to taxonomically revise the extensive and scattered herbarium collections, has led to the running of some bryophyte workshops and training of new Sri Lankan bryologists. The ultimate goal of these efforts is to produce the first comprehensive bryophyte flora of the country, and priorities for future work are outlined.  相似文献   
90.
The late Pleistocene site of Oerel which represents the Eemian and the Weichselian interstadials Brörup, Odderade, Oerel and Glinde as well as parts of the stadials Herning and Rederstall was investigated for botanical remains such as fruits, seeds, wood, leaves and mosses, as well as insect remains. A large number of taxa were identified. They show the different environmental conditions, in particular several changes of water level leading to the formation of lakes and diverse forms of mires up to raised bogs. The trophic conditions, too, changed several times. The macrofossil record supports the pollen evidence of dense forests during the two early Weichselian interstadials and tundra vegetation during the later ones. Several indicator species show comparably warm summers but very cold winters during the Brörup and Odderade while the climate during Oerel and Glinde was generally cool. Climatic reconstructions using the MCR method were performed on the basis of the beetle finds.  相似文献   
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