通过对长江中游地区野生百合资源进行调查,发现长江中游地区有野生百合资源14个种和3个变种即野百合(Lilium brownii F. E. Brown ex Miellez var. brownii)、百合(L. brownii F. E. Brown ex Miellez var. viridulum Baker)、宜昌百合(...通过对长江中游地区野生百合资源进行调查,发现长江中游地区有野生百合资源14个种和3个变种即野百合(Lilium brownii F. E. Brown ex Miellez var. brownii)、百合(L. brownii F. E. Brown ex Miellez var. viridulum Baker)、宜昌百合(L. leucanthum (Baker) Baker)、渥丹(L. concolor Salisb. var. concolor)、有斑百合(L. concolor Sali sb. var. pulchellum (Fisch.)Regel)、滇百合(L. baberianum Coll.et Hemsl)、大理百合(L.taliense Franch.)、药百合(L.speciosum Thunb. var. gloriosoides Baker)、湖北百合(L.henryi Baker)、南川百合(L. rosthornii Diels)、宝兴百合(L. duchartrei Franch.)、山丹(L. pumilum DC.)、川百合(L. davidii Duchartre)、条叶百合(L. callosum Sieb. et Zucc.)、乳头百合(L. papilliferum Franch.)、绿花百合(L. fargesii Franch.)和卷丹(L. tigrinum Ker Gawler)。对野生百合在长江中游地区分布现状、观赏特性及开发利用价值进行了分析,为百合新品种培育奠定基础。同时对长江中游地区野生百合资源的保护和合理开发利用提出建议。展开更多
A stalagmite in Qingjiang, Hubei, has yielded the records of hydrogen and oxygen as well as carbon isotopic changes and provided a climate history of 9000 years. The hydrogen iso-topic ratio in fluid inclusions and th...A stalagmite in Qingjiang, Hubei, has yielded the records of hydrogen and oxygen as well as carbon isotopic changes and provided a climate history of 9000 years. The hydrogen iso-topic ratio in fluid inclusions and the oxygen isotopic ratio in stalagmite calcite are controlled by meteoric water, which is in response to ambient temperature or precipitation amount. The carbon isotopic ratio, sensitive to the nature of vegetation, also can be used to reconstruct the climate history. The carbon-14 and U-series dated stalagmite records reveal that climate oscillated in the middle reach of Yangtze river over the past 9000 years:(1) 9.0-6.5 kaBP, a cooler and more humid condition; (2) 6.5-4.0 kaBP,with warmer and drier weather; (3) 4.0-2.0 kaBP, cold weather with heavy precipitation, and (4)2.0 kaBP to present, tendency to be warmer and drier.展开更多
Flood disaster has been a serious hidden danger since the ancient time. The essential cause for the fact that floods have not been eliminated for hundreds of years is that time honored strategies do not suit the case...Flood disaster has been a serious hidden danger since the ancient time. The essential cause for the fact that floods have not been eliminated for hundreds of years is that time honored strategies do not suit the cases of flood prevention. In the view of geological environmental analyses of flood formation and from the synthesis of experiences gained in flood control in the past hundreds of years, sluggish draining of flood, silt sedimentation in channel and building levee blindly constitute the main cause of intractable flood for a long time in the middle reach of the Yangtze River. Draining away silt and water is the only way to stamping out flood disaster. Opening up artificial waterways for flood diversion, draining away the silt of channel into the polders, and storing the flood water are important engineering measures for the flood control and damage reduction.展开更多
文摘通过对长江中游地区野生百合资源进行调查,发现长江中游地区有野生百合资源14个种和3个变种即野百合(Lilium brownii F. E. Brown ex Miellez var. brownii)、百合(L. brownii F. E. Brown ex Miellez var. viridulum Baker)、宜昌百合(L. leucanthum (Baker) Baker)、渥丹(L. concolor Salisb. var. concolor)、有斑百合(L. concolor Sali sb. var. pulchellum (Fisch.)Regel)、滇百合(L. baberianum Coll.et Hemsl)、大理百合(L.taliense Franch.)、药百合(L.speciosum Thunb. var. gloriosoides Baker)、湖北百合(L.henryi Baker)、南川百合(L. rosthornii Diels)、宝兴百合(L. duchartrei Franch.)、山丹(L. pumilum DC.)、川百合(L. davidii Duchartre)、条叶百合(L. callosum Sieb. et Zucc.)、乳头百合(L. papilliferum Franch.)、绿花百合(L. fargesii Franch.)和卷丹(L. tigrinum Ker Gawler)。对野生百合在长江中游地区分布现状、观赏特性及开发利用价值进行了分析,为百合新品种培育奠定基础。同时对长江中游地区野生百合资源的保护和合理开发利用提出建议。
基金This work was supported by the National Natural Science Foundation of China (Grant No. 49772171 and 9672135).
文摘A stalagmite in Qingjiang, Hubei, has yielded the records of hydrogen and oxygen as well as carbon isotopic changes and provided a climate history of 9000 years. The hydrogen iso-topic ratio in fluid inclusions and the oxygen isotopic ratio in stalagmite calcite are controlled by meteoric water, which is in response to ambient temperature or precipitation amount. The carbon isotopic ratio, sensitive to the nature of vegetation, also can be used to reconstruct the climate history. The carbon-14 and U-series dated stalagmite records reveal that climate oscillated in the middle reach of Yangtze river over the past 9000 years:(1) 9.0-6.5 kaBP, a cooler and more humid condition; (2) 6.5-4.0 kaBP,with warmer and drier weather; (3) 4.0-2.0 kaBP, cold weather with heavy precipitation, and (4)2.0 kaBP to present, tendency to be warmer and drier.
基金The research is supported by the National Natural Science F ounda-tion of China( No.49972 0 5 7) and the China Geological Surv
文摘Flood disaster has been a serious hidden danger since the ancient time. The essential cause for the fact that floods have not been eliminated for hundreds of years is that time honored strategies do not suit the cases of flood prevention. In the view of geological environmental analyses of flood formation and from the synthesis of experiences gained in flood control in the past hundreds of years, sluggish draining of flood, silt sedimentation in channel and building levee blindly constitute the main cause of intractable flood for a long time in the middle reach of the Yangtze River. Draining away silt and water is the only way to stamping out flood disaster. Opening up artificial waterways for flood diversion, draining away the silt of channel into the polders, and storing the flood water are important engineering measures for the flood control and damage reduction.
