Fragrant camphor tree is the city tree of Hangzhou which takes a large proportion of the ancient trees in Hangzhou City. Recently, with the free open of the attractions around the West Lake and the implementation of t...Fragrant camphor tree is the city tree of Hangzhou which takes a large proportion of the ancient trees in Hangzhou City. Recently, with the free open of the attractions around the West Lake and the implementation of the comprehensive pro- ject for protecting the West Lake, a part of ancient fragrant camphor trees are fac- ing problems such as altered living conditons. Some of them are showing a decline in growth vigor or even close to death, which will produce extremely negative influ- ences on the maintaining and sustainable development of the West Lake Scenic Area if without any timely measures for the rescue and rejuvenation of the trees. Therefore, strengthening the protection and management of ancient fragrant camphor trees at the West Lake Scenic Area and carrying out researches on the procedure for diagnosing the reasons for the growth recession of the ancient fragrant camphor trees at the West Lake Scenic Area are of great significance for the future protec- tion and rejuvenation of the ancient trees around the West Lake. The factors influ- encing the growth of ancient trees and indexes for judging the growth condition were listed and the reasons for the growth recession were systematically summa- rized in this paper. In addition, measures for the rejuvenation of the ancient fragrant camphor trees were also simply discussed.展开更多
Northwest China includes Xinjiang Ugyur Autonomous Region, Qinghai Province, Gansu Province, Ningxia Hui Autonomous Region and Shaanxi Province, covering 308×10^4km^2. It is located in the warm-temperate zone and...Northwest China includes Xinjiang Ugyur Autonomous Region, Qinghai Province, Gansu Province, Ningxia Hui Autonomous Region and Shaanxi Province, covering 308×10^4km^2. It is located in the warm-temperate zone and the climate is arid or semi-arid. Precipitation is very scarce but evaporation is extremely high. The climate is dry, the water resources are deficient, the ecoenvironment is fragile, and the distribution of water resources is uneven. In this region, precipitation is the only input, and evaporation is the only output in the inland rivers, and precipitation, surface water and groundwater change with each other for many times, which benefits the storage and utilization of water resources. The average precipitation in this region is 232 mm, the total precipitation amount is 7003×108m^3/a, the surface water resources are 1891×10^8m^3/a, the total natural groundwater resources are 1150×10^8m^3/a, the total available water resources are 438×10^8 m^3/a, and the total water resources are 1996×10^8m^3/a and per capita water resources are 2278 m^3/a. The water resources of the whole area are 5.94×10^4m^3/(a.km^2), being only one-fifth of the mean value in China. Now, the available water resources are 876×10^8m^3/a, among which groundwater is proximate 130×10^8m^3/a.展开更多
In this paper, based on the observational data of 1995 in the Chinese Antarctic Great Wall Station the snowstorm is studied synoptically. It is found that there are two kinds of snowstorms with different physical char...In this paper, based on the observational data of 1995 in the Chinese Antarctic Great Wall Station the snowstorm is studied synoptically. It is found that there are two kinds of snowstorms with different physical characteristics and that the happening of snowstorm is always accompanied by a near-ground level inversion layer. The function of the inversion layer is analyzed, too. It is indicated that the strong ESE-wind type snowstorm is mainly caused by katabatic wind and gradient wind together. This idea is new and different from the general concept that there is no katabatic wind in the western Antarctic area.展开更多
This paper describes results of the fluxes of momentum , sensible heat and latent heat for the West Pacific Tropical Ocean Area ( 127 ° E - 150 ° E , 5 ° N -3 ° S ). The data were collected by the ...This paper describes results of the fluxes of momentum , sensible heat and latent heat for the West Pacific Tropical Ocean Area ( 127 ° E - 150 ° E , 5 ° N -3 ° S ). The data were collected by the small tethered balloon sounding system over this ocean area including 6 continuous stations (140 ° E. 0 ° ; 145 ° E, 0 ° ; 150 ° E, 0 ° ; 140° E, 5 ° N; 145 ° E, 5° N and 150 ° E, 5 ° N) from 11 October to 15 December, 1986 . These fluxes were calculated by the semiempirical flux-profile relationships of Monin-Obukhov similarity theory using these observed data. The results show that for this tropical ocean area the drag coefficient CD is equal to (1.53 ± 0.25) × 10 3 and the daily mean latent flux Hl is greater than its daily mean sensible flux HV by a factor of about 9.展开更多
Taking 8 parks in Xihu Scenic Area as the survey objects, this study found that there are 77 kinds of shade-tolerant lawns and ground cover plants under the forest in good growth condition, and there are 3 types of ap...Taking 8 parks in Xihu Scenic Area as the survey objects, this study found that there are 77 kinds of shade-tolerant lawns and ground cover plants under the forest in good growth condition, and there are 3 types of application forms: dense forest, sparse forest and forest edge. In response to the existing problems, it is proposed that it is necessary to adhere to principles of ecology, adapt to local conditions and plant suitable varieties in accordance with local conditions, develop and use new varieties of wild shade-tolerant lawns and ground cover plants, and strengthen the promotion of the mixed planting model of shade-tolerant lawns and ground cover plants, so as to provide guidance for the better use of shade-tolerant lawns and ground cover under the forest in the West Lake Scenic Area in the future.展开更多
The operation of reservoir(s) has a certain impact on the downstream hydrologic regime,and even endangers the ecological water safety of river corridor and ecosystems which interact with river system.Therefore,ecologi...The operation of reservoir(s) has a certain impact on the downstream hydrologic regime,and even endangers the ecological water safety of river corridor and ecosystems which interact with river system.Therefore,ecological operation needs to be carried out in order to ensure ecological water use of downstream zone.The key technological support is the estimation and integrated calculation of ecological water demand.The connotation of the integrated calculation on ecological water demand lies on that the ecological water demand of different ecosystems is integrated to meet the requirements of water allocation and operation on watershed scale in terms of hydrological cycle.Considering the practical requirement of ecological operation of reservoir(s),this study proposed an integrated calculation approach of ecological water demand according to the ecological water demand in various ecosystems as well as the hydraulic connection among them;it established an integrated calculation model of regional ecological water demand by means of the distributed hydrological model,and studied the integrated calculation in Yalong River basin which is the source area of the west route of South-North Water Transfer Project as an example.The results indicated that the integrated calculation model more effectively combined the ecological water demand and hydraulic connection of ecosystems in time and space,compared with the lumped water balance analysis,since the former conquered the defect of insufficient ecological water source and supplement on multiple spatial and temporal scales,and met the demand of ecological operation of reservoir(s).展开更多
基金Supported by the Key Project of Hangzhou Bureau for Gardens and Cultural Relics(2009-003)~~
文摘Fragrant camphor tree is the city tree of Hangzhou which takes a large proportion of the ancient trees in Hangzhou City. Recently, with the free open of the attractions around the West Lake and the implementation of the comprehensive pro- ject for protecting the West Lake, a part of ancient fragrant camphor trees are fac- ing problems such as altered living conditons. Some of them are showing a decline in growth vigor or even close to death, which will produce extremely negative influ- ences on the maintaining and sustainable development of the West Lake Scenic Area if without any timely measures for the rescue and rejuvenation of the trees. Therefore, strengthening the protection and management of ancient fragrant camphor trees at the West Lake Scenic Area and carrying out researches on the procedure for diagnosing the reasons for the growth recession of the ancient fragrant camphor trees at the West Lake Scenic Area are of great significance for the future protec- tion and rejuvenation of the ancient trees around the West Lake. The factors influ- encing the growth of ancient trees and indexes for judging the growth condition were listed and the reasons for the growth recession were systematically summa- rized in this paper. In addition, measures for the rejuvenation of the ancient fragrant camphor trees were also simply discussed.
基金National Natural Science Foundation of China, No.40235053 No.40401012+1 种基金 AIACC, No.AS25 Lanzhou Jiaotong University Foundation
文摘Northwest China includes Xinjiang Ugyur Autonomous Region, Qinghai Province, Gansu Province, Ningxia Hui Autonomous Region and Shaanxi Province, covering 308×10^4km^2. It is located in the warm-temperate zone and the climate is arid or semi-arid. Precipitation is very scarce but evaporation is extremely high. The climate is dry, the water resources are deficient, the ecoenvironment is fragile, and the distribution of water resources is uneven. In this region, precipitation is the only input, and evaporation is the only output in the inland rivers, and precipitation, surface water and groundwater change with each other for many times, which benefits the storage and utilization of water resources. The average precipitation in this region is 232 mm, the total precipitation amount is 7003×108m^3/a, the surface water resources are 1891×10^8m^3/a, the total natural groundwater resources are 1150×10^8m^3/a, the total available water resources are 438×10^8 m^3/a, and the total water resources are 1996×10^8m^3/a and per capita water resources are 2278 m^3/a. The water resources of the whole area are 5.94×10^4m^3/(a.km^2), being only one-fifth of the mean value in China. Now, the available water resources are 876×10^8m^3/a, among which groundwater is proximate 130×10^8m^3/a.
文摘In this paper, based on the observational data of 1995 in the Chinese Antarctic Great Wall Station the snowstorm is studied synoptically. It is found that there are two kinds of snowstorms with different physical characteristics and that the happening of snowstorm is always accompanied by a near-ground level inversion layer. The function of the inversion layer is analyzed, too. It is indicated that the strong ESE-wind type snowstorm is mainly caused by katabatic wind and gradient wind together. This idea is new and different from the general concept that there is no katabatic wind in the western Antarctic area.
文摘This paper describes results of the fluxes of momentum , sensible heat and latent heat for the West Pacific Tropical Ocean Area ( 127 ° E - 150 ° E , 5 ° N -3 ° S ). The data were collected by the small tethered balloon sounding system over this ocean area including 6 continuous stations (140 ° E. 0 ° ; 145 ° E, 0 ° ; 150 ° E, 0 ° ; 140° E, 5 ° N; 145 ° E, 5° N and 150 ° E, 5 ° N) from 11 October to 15 December, 1986 . These fluxes were calculated by the semiempirical flux-profile relationships of Monin-Obukhov similarity theory using these observed data. The results show that for this tropical ocean area the drag coefficient CD is equal to (1.53 ± 0.25) × 10 3 and the daily mean latent flux Hl is greater than its daily mean sensible flux HV by a factor of about 9.
基金Supported by the Study on Screening and Application of Shade-tolerant Lawn Plants(S202210341019)。
文摘Taking 8 parks in Xihu Scenic Area as the survey objects, this study found that there are 77 kinds of shade-tolerant lawns and ground cover plants under the forest in good growth condition, and there are 3 types of application forms: dense forest, sparse forest and forest edge. In response to the existing problems, it is proposed that it is necessary to adhere to principles of ecology, adapt to local conditions and plant suitable varieties in accordance with local conditions, develop and use new varieties of wild shade-tolerant lawns and ground cover plants, and strengthen the promotion of the mixed planting model of shade-tolerant lawns and ground cover plants, so as to provide guidance for the better use of shade-tolerant lawns and ground cover under the forest in the West Lake Scenic Area in the future.
基金supported by the Foundation for Innovative Research Groups of the National Natural Science Foundation of China (Grant No. 51021066)the State Key Development Program for Basic Research of China (Grant No. 2010CB951102)
文摘The operation of reservoir(s) has a certain impact on the downstream hydrologic regime,and even endangers the ecological water safety of river corridor and ecosystems which interact with river system.Therefore,ecological operation needs to be carried out in order to ensure ecological water use of downstream zone.The key technological support is the estimation and integrated calculation of ecological water demand.The connotation of the integrated calculation on ecological water demand lies on that the ecological water demand of different ecosystems is integrated to meet the requirements of water allocation and operation on watershed scale in terms of hydrological cycle.Considering the practical requirement of ecological operation of reservoir(s),this study proposed an integrated calculation approach of ecological water demand according to the ecological water demand in various ecosystems as well as the hydraulic connection among them;it established an integrated calculation model of regional ecological water demand by means of the distributed hydrological model,and studied the integrated calculation in Yalong River basin which is the source area of the west route of South-North Water Transfer Project as an example.The results indicated that the integrated calculation model more effectively combined the ecological water demand and hydraulic connection of ecosystems in time and space,compared with the lumped water balance analysis,since the former conquered the defect of insufficient ecological water source and supplement on multiple spatial and temporal scales,and met the demand of ecological operation of reservoir(s).