The Rhines effect may be regarded as an interaction between Rossby waves and turbulence, in which the Rossby waves may radiate away eddy energy when their frequencies are equal or larger than those of the turbulence,t...The Rhines effect may be regarded as an interaction between Rossby waves and turbulence, in which the Rossby waves may radiate away eddy energy when their frequencies are equal or larger than those of the turbulence,thereby deforming and eventually destroying the existing eddies. Through comparing eddy-scale velocity and long Rossby wave phase speed in the oceans, a generalized form of the Rhines effect is examined on the geographical characteristics of altimeter-observed eddies. The results show that the generalized Rhines effect has a much greater influence on eddy characteristics than its classical form, which only considers the simple beta effect due to the meridional gradient of planetary vorticity. The largest amount of eddies are detected in regions where eddy-scale velocity is larger than the critical Rossby-wave phase speed considering a generalized beta effect. The eddies in those regions can grow via an inverse kinetic energy cascade and have much larger amplitudes and sizes. The ＂eddy desert＂ regions outside of the tropical oceans, which have far fewer detected eddies and much weaker eddy amplitudes, lie in areas where the eddy-scale velocity is less than the critical Rossby-wave phase speed. In those regions, the generalized Rhines effect may be a possible mechanism of suppressing eddy growth.展开更多
The Wesel-Xanten stretch of the fiver Rhine between km-812.5 and km-821.5 is one of the reaches where strong erosion leads to high maintenance efforts conceming navigability.In order to improve the naviga- tion condit...The Wesel-Xanten stretch of the fiver Rhine between km-812.5 and km-821.5 is one of the reaches where strong erosion leads to high maintenance efforts conceming navigability.In order to improve the naviga- tion conditions without aggravating the flood protection,but also ensuring that the ecological system of the river is not damaged,investigations of the morphodynamical processes in connection with artificial grain feeding ac- tivities have to be carried out by Federal Waterways Engineering and Research...展开更多
This study demonstrates that a regionally extinct bird species belonging to the long-distance migrants can be reintroduced under the right circumstances.The article first describes the historic distribution of the whi...This study demonstrates that a regionally extinct bird species belonging to the long-distance migrants can be reintroduced under the right circumstances.The article first describes the historic distribution of the white stork(Ciconia ciconia)prior to its disappearance from the Alpine Rhine Valley.Furthermore,the study examines the increase in actual population size between 1984 and 2018,mean reproductive success per breeding pair in the Rhine Valley between 2011 and 2018 and compares different types of breeding sites.Finally,the factors facilitating the successful reintroduction of the species are discussed.展开更多
[Objective]The aim is to improve the local goose in Heilongjiang Province（ Zi goose,Huo goose,Heilongjiang white sticky goose） growth rate and production performance,increase the goose economic benefits and change t...[Objective]The aim is to improve the local goose in Heilongjiang Province（ Zi goose,Huo goose,Heilongjiang white sticky goose） growth rate and production performance,increase the goose economic benefits and change the resource advantage of local into commercial and economic advantages. [Methods]Rhine goose of large size,fast growth,high wool and cashmere was introduced on hybrid improvement. [Results] Improved goose 60 days of age weight was 3. 240 kg,1. 40 kg higher than that of local goose weight; Improved adult male goose weight were 4. 661 kg,female goose 4. 150 kg,0. 50 kg or 0. 80 kg higher than the local goose weight respectively; Improved goose fleece production was 110. 03 g,fleece rate 29. 17%,33. 15 g higher than the local goose prolific wool,fleece rate increased by 12. 71%. [Conclusion] Effect of using Rhine goose to improve Heilongjiang local goose obvious and economic benefit is improved.展开更多
Recent invasions by non-native gobiid fish species that are ongoing in the Western European rivers Rhine and Meuse, will lead to interactions with native benthic fish species. Since both non-native gobiids and native ...Recent invasions by non-native gobiid fish species that are ongoing in the Western European rivers Rhine and Meuse, will lead to interactions with native benthic fish species. Since both non-native gobiids and native benthic species are bottom dwelling species with a preference for shelter during at least part of their life cycle, it is likely that competition for shelter will occur between these non-native and native species when shelter is a limiting factor. To investigate the importance of this mecha- nism for species replacements, various habitat choice experiments were conducted between two common native benthic fish spe- cies （Cottus perifretum and Barbatula barbatula） and four invasive non-native gobiid species （Proterorhinus semilunaris, Neogo- bius melanostomus, N. kessleri and N. fluviatilis）. The first series of single specimen experiments determined the habitat choice of each individual fish species. In a second series of competition experiments, shifts in habitat choice in comparison with the previ- ously observed habitat choice, were determined when a native benthic fish species co-occurred with non-native gobiid species. Native C. perifretum displayed a significant shift in habitat choice in co-occurrence with the gobiids N. kessleri or P. semilunaris. C. perifretum was outcompeted and moved from the available shelter place to less preferred habitat types. During the competition experiments no change in habitat choice of B. barbatula was shown. Our study therefore suggests that competition for shelter is likely to occur in rivers invaded by N. kessleri and P. semilunaris at sites where shelter is limiting展开更多
This paper describes the effects that temperature changes in the Rhine river distributaries have on native and exotic fish diversity. Site-specific potentially affected fractions （PAFs） of the regional fish species ...This paper describes the effects that temperature changes in the Rhine river distributaries have on native and exotic fish diversity. Site-specific potentially affected fractions （PAFs） of the regional fish species pool were derived using species sensitivity distributions （SSDs） for water temperature. The number of fish species in the river distributaries has changed remarkably over the last century. The number of native rheophilous species declined up until 1980 due to anthropogenic disturbances such as commercial fishing, fiver regulation, migration barriers, habitat deterioration and water pollution. In spite of progress in river re- habilitation, the native rheophilous fish fauna has only partially recovered thus far. The total number of species has strongly in- creased due to the appearance of more exotic species. After the opening of the Rhine-Main-Danube waterway in 1992, many fish species originating from the Ponto-Caspian area colonized the Rhine basin. The yearly minimum and maximum river tempera- tures at Lobith have increased by circa 4 ~C over the period 1908-2010. Exotic species show lower PAFs than native species at both ends of the temperature range. The interspecific variation in the temperature tolerance of exotic fish species was found to be large. Using temporal trends in river temperature allowed past predictions of PAFs to demonstrate that the increase in maximum river temperature negatively affected a higher percentage of native fish species than exotic species. Our results support the hy- pothesis that alterations of the river Rhine＇s temperature regime caused by thermal pollution and global wanning limit the full recovery of native fish fauna and facilitate the establishment of exotic species which thereby increases competition between native and exotic species. Thermal refuges are important for the survival of native fish species under extreme summer or winter temperature conditions展开更多
ON June 2,1997,"The Cultural Express Train" from France came to us as swiftly sa wind and the Chinese audience had the honor to apreciate the splendid performance of France’s Rhine Ballet Troupe in the eleg...ON June 2,1997,"The Cultural Express Train" from France came to us as swiftly sa wind and the Chinese audience had the honor to apreciate the splendid performance of France’s Rhine Ballet Troupe in the elegant Beijing Exhibition Hall Theater. From a historica view of ballet internationally, France’s Rhine Ballet Troupe,established just 25 years ago,is apromising new arrival on the performing arts scene.As far as full-length ballets are concerned,only large troupes with considerable strength have the展开更多
There is a beautiful city in southwestern Germany,lying on the southern bank of the Rhine River,which has flowed quietly nearby since ancient times.The city was the hometown of Johannes Gutenberg,the inventor of moder...There is a beautiful city in southwestern Germany,lying on the southern bank of the Rhine River,which has flowed quietly nearby since ancient times.The city was the hometown of Johannes Gutenberg,the inventor of modern typography,as well as of an excellent Bundesliga soccer team.It features a combination of ancient flavor and modern fashion,with not only time-honored churches展开更多
基金The National Natural Science Foundation of China under contract No.41276026the Ocean Strategic Pilot Project of Chinese Academy of Sciences under contract No.XDA11020301the Key Program of National Natural Science Foundation of China under contract No.61233013
文摘The Rhines effect may be regarded as an interaction between Rossby waves and turbulence, in which the Rossby waves may radiate away eddy energy when their frequencies are equal or larger than those of the turbulence,thereby deforming and eventually destroying the existing eddies. Through comparing eddy-scale velocity and long Rossby wave phase speed in the oceans, a generalized form of the Rhines effect is examined on the geographical characteristics of altimeter-observed eddies. The results show that the generalized Rhines effect has a much greater influence on eddy characteristics than its classical form, which only considers the simple beta effect due to the meridional gradient of planetary vorticity. The largest amount of eddies are detected in regions where eddy-scale velocity is larger than the critical Rossby-wave phase speed considering a generalized beta effect. The eddies in those regions can grow via an inverse kinetic energy cascade and have much larger amplitudes and sizes. The ＂eddy desert＂ regions outside of the tropical oceans, which have far fewer detected eddies and much weaker eddy amplitudes, lie in areas where the eddy-scale velocity is less than the critical Rossby-wave phase speed. In those regions, the generalized Rhines effect may be a possible mechanism of suppressing eddy growth.
文摘The Wesel-Xanten stretch of the fiver Rhine between km-812.5 and km-821.5 is one of the reaches where strong erosion leads to high maintenance efforts conceming navigability.In order to improve the naviga- tion conditions without aggravating the flood protection,but also ensuring that the ecological system of the river is not damaged,investigations of the morphodynamical processes in connection with artificial grain feeding ac- tivities have to be carried out by Federal Waterways Engineering and Research...
文摘This study demonstrates that a regionally extinct bird species belonging to the long-distance migrants can be reintroduced under the right circumstances.The article first describes the historic distribution of the white stork(Ciconia ciconia)prior to its disappearance from the Alpine Rhine Valley.Furthermore,the study examines the increase in actual population size between 1984 and 2018,mean reproductive success per breeding pair in the Rhine Valley between 2011 and 2018 and compares different types of breeding sites.Finally,the factors facilitating the successful reintroduction of the species are discussed.
基金Colleges and Universities in Heilongjiang Province Science and Technology Innovation Team Building Project(2010td02)Heilongjiang Academy of Agricultural Sciences Innovation Project
文摘[Objective]The aim is to improve the local goose in Heilongjiang Province（ Zi goose,Huo goose,Heilongjiang white sticky goose） growth rate and production performance,increase the goose economic benefits and change the resource advantage of local into commercial and economic advantages. [Methods]Rhine goose of large size,fast growth,high wool and cashmere was introduced on hybrid improvement. [Results] Improved goose 60 days of age weight was 3. 240 kg,1. 40 kg higher than that of local goose weight; Improved adult male goose weight were 4. 661 kg,female goose 4. 150 kg,0. 50 kg or 0. 80 kg higher than the local goose weight respectively; Improved goose fleece production was 110. 03 g,fleece rate 29. 17%,33. 15 g higher than the local goose prolific wool,fleece rate increased by 12. 71%. [Conclusion] Effect of using Rhine goose to improve Heilongjiang local goose obvious and economic benefit is improved.
文摘Recent invasions by non-native gobiid fish species that are ongoing in the Western European rivers Rhine and Meuse, will lead to interactions with native benthic fish species. Since both non-native gobiids and native benthic species are bottom dwelling species with a preference for shelter during at least part of their life cycle, it is likely that competition for shelter will occur between these non-native and native species when shelter is a limiting factor. To investigate the importance of this mecha- nism for species replacements, various habitat choice experiments were conducted between two common native benthic fish spe- cies （Cottus perifretum and Barbatula barbatula） and four invasive non-native gobiid species （Proterorhinus semilunaris, Neogo- bius melanostomus, N. kessleri and N. fluviatilis）. The first series of single specimen experiments determined the habitat choice of each individual fish species. In a second series of competition experiments, shifts in habitat choice in comparison with the previ- ously observed habitat choice, were determined when a native benthic fish species co-occurred with non-native gobiid species. Native C. perifretum displayed a significant shift in habitat choice in co-occurrence with the gobiids N. kessleri or P. semilunaris. C. perifretum was outcompeted and moved from the available shelter place to less preferred habitat types. During the competition experiments no change in habitat choice of B. barbatula was shown. Our study therefore suggests that competition for shelter is likely to occur in rivers invaded by N. kessleri and P. semilunaris at sites where shelter is limiting
文摘This paper describes the effects that temperature changes in the Rhine river distributaries have on native and exotic fish diversity. Site-specific potentially affected fractions （PAFs） of the regional fish species pool were derived using species sensitivity distributions （SSDs） for water temperature. The number of fish species in the river distributaries has changed remarkably over the last century. The number of native rheophilous species declined up until 1980 due to anthropogenic disturbances such as commercial fishing, fiver regulation, migration barriers, habitat deterioration and water pollution. In spite of progress in river re- habilitation, the native rheophilous fish fauna has only partially recovered thus far. The total number of species has strongly in- creased due to the appearance of more exotic species. After the opening of the Rhine-Main-Danube waterway in 1992, many fish species originating from the Ponto-Caspian area colonized the Rhine basin. The yearly minimum and maximum river tempera- tures at Lobith have increased by circa 4 ~C over the period 1908-2010. Exotic species show lower PAFs than native species at both ends of the temperature range. The interspecific variation in the temperature tolerance of exotic fish species was found to be large. Using temporal trends in river temperature allowed past predictions of PAFs to demonstrate that the increase in maximum river temperature negatively affected a higher percentage of native fish species than exotic species. Our results support the hy- pothesis that alterations of the river Rhine＇s temperature regime caused by thermal pollution and global wanning limit the full recovery of native fish fauna and facilitate the establishment of exotic species which thereby increases competition between native and exotic species. Thermal refuges are important for the survival of native fish species under extreme summer or winter temperature conditions
文摘ON June 2,1997,"The Cultural Express Train" from France came to us as swiftly sa wind and the Chinese audience had the honor to apreciate the splendid performance of France’s Rhine Ballet Troupe in the elegant Beijing Exhibition Hall Theater. From a historica view of ballet internationally, France’s Rhine Ballet Troupe,established just 25 years ago,is apromising new arrival on the performing arts scene.As far as full-length ballets are concerned,only large troupes with considerable strength have the
文摘There is a beautiful city in southwestern Germany,lying on the southern bank of the Rhine River,which has flowed quietly nearby since ancient times.The city was the hometown of Johannes Gutenberg,the inventor of modern typography,as well as of an excellent Bundesliga soccer team.It features a combination of ancient flavor and modern fashion,with not only time-honored churches
