Based on the introduction about the gardening conception,layout and method of Chengde Imperial Summer Resort,this study analyzed the eco-consciousness in the gardening and the landscape benefits,ecological benefits,so...Based on the introduction about the gardening conception,layout and method of Chengde Imperial Summer Resort,this study analyzed the eco-consciousness in the gardening and the landscape benefits,ecological benefits,social benefits and economic benefits it has generated.展开更多
[Objective] The aim was to study the willingness to accept compensation and compensation sharing of returning land for farming to forestry in Zhangjiakou and Chengde region.[Method] Based on the investigation of farm...[Objective] The aim was to study the willingness to accept compensation and compensation sharing of returning land for farming to forestry in Zhangjiakou and Chengde region.[Method] Based on the investigation of farmers’ willingness to accept ecological compensation in Zhangjiakou and Chengde region,farmers’ willingness to accept compensation was quantized,and the calculation model of sharing rate of ecological compensation was established,finally the sharing rate of ecological compensation was calculated choosing water supply quantity as reference.[Result] Farmers’ willingness to accept compensation in Zhangjiakou and Chengde region was 2 740.5 yuan/(hm2·a),and returned farmland area was 429 700 hm2 in 2008,so the willingness to accept ecological compensation was up to 1.178 billion yuan/a.In addition,the ecological compensation sharing rate of government was 37.60% in Beijing,42.75% in Tianjing and 19.64% in Tangshan,and their ecological compensation funds were 443,504 and 231 million yuan,respectively.[Conclusion] The study could provide important foundation for the establishment of ecological compensation standard and implementation of ecological compensation in Zhangjiakou and Chengde region.展开更多
Air pollution history of sulphur and heavy metals since 1800 in Chengde City , north China,was studied by analyzing the concentrations of sulphur and heavy metals in growth rings of Pinus tabulaeformis Carr. Sulphur c...Air pollution history of sulphur and heavy metals since 1800 in Chengde City , north China,was studied by analyzing the concentrations of sulphur and heavy metals in growth rings of Pinus tabulaeformis Carr. Sulphur concentrations in the tree rings of 1910-1920, 1970-1980,and 1980-1990 have increased 1-2 , 3-5 and 10 times respectively as those in the tree ring of 1810-1820 (P<0. 05). This is ascribed to the result of urbanization, especially the appearance and aggravation of industrialization, in the city of Chengde since 1950s. Fe appeared to increase during 1920-1940, possibly due to the opening of Damiao Iron Mine by the Japanese in 1927; Mn increased throughout the whole history, from 4. 1 μg/g(1840- 1850) to 10. 4 μg/g (1980 1990,P <0. 05);Pb did not increase until 1980 but increased sharply during the last 10 years by 560%(P<0. 001). This is caused by the increased number of automobiles in the city. The contents of Cu,Zn, Ni have changed little. The concentrations of sulphur and heavy metals in the tree rings at the beginning of 1800s were the lowest and could be regarded as the background concentrations.We calculated that S, Fe, Pb, Mn, Ni, and Zn in the tree rings have increased 10, 2.4,1.8,1.5,1.0 and 0. 8 times respectively during the past 190 years or so. The results showed that serious environmental pollution, especially air pollution of SO2,has occurred since 1949 when the People's Republic of China was founded.展开更多
Chengde City,famous for its cultural sightseeing tourism industry,and is located in China's"Capital Holiday Tourism Circle".This location is advantageous,because of the recent boom in China's nationa...Chengde City,famous for its cultural sightseeing tourism industry,and is located in China's"Capital Holiday Tourism Circle".This location is advantageous,because of the recent boom in China's national tourism industry.This industry has gone through several structural and development changes with in the past several years.A result of these restructuring patterns is the great changes concerning competitive and cooperative relations among tourism destinations,which have precipitated the decline of the traditional sightseeing pattern. Northern China's"Capital Holiday Tourism Circle"is one of nine key areas within the Chinese tourism industry under development during the Eleventh Five-Year Plan.In the present article the method of"Distance Decline of The Tourist Flow"was used to define the flow of tourists in the Capital Holiday Tourism Circle and its influence upon Chengde's tourism spatial distribution.3 aspects will be discussed:(1)The transformation from sightseeing to leisure markets makes the change possible in Chengde's tourism spatial pattern.(2)The location advantage(adjacent to Beijing and Tianjin) also leads to the change in Chengde tourism spatial pattern.(3)The establishment of freeways also contributes to a great degrees of change. The rapid development of leisure tourism might lead to the change from nucleus model to a diversified one within Chengde's tourism.Specifically,Chengde is developing the tourism industry with the central heritage area as the nucleus and the northern forest, pasture,southern mountain,and rivers as its periphery.展开更多
In order to probe the geochemical relationship between the quality of economic crops and ecological geochemistry,this project studies the chestnut production area of Chengde City,Hebei Province,China.The chemical weat...In order to probe the geochemical relationship between the quality of economic crops and ecological geochemistry,this project studies the chestnut production area of Chengde City,Hebei Province,China.The chemical weathering index,chemical depletion fraction CDF,mass transfer coefficient,and bioconcentration coefficient were used to quantify the characteristics of element migration and accumulation in the BRSPC(Bedrock–Regolith–Soil–Plant Continuum system)system of gneiss formation area and dolomite formation area.The results show that the soil CaO,SiO_(2),Al_(2)O_(3),and Na_(2)O elements in the gneiss construction area are abundant,and the B,Ge,S,and Mo elements are relatively lacking;the soil B,Mo and Ge elements in the dolomite construction area are abundant,and the SiO_(2),Al_(2)O_(3),and Na_(2)O elements are slightly lower;The weathering intensity of gneiss is low-medium,with the relatively high mobility and apparent transformation of Se,B,V,S,Mn,and Mo.The weathering intensity of dolostone is low,with the relatively high mobility and apparent transformation of Na_(2)O,P,and Ni.Chestnut is rich in Cu,Ni,Se,and Ge,walnut has a high content of Mo,and hawthorn is rich in Se and B.The contents of Mn in chestnut are 1–2 times higher in walnut and hawthorn.It lays the theoretical foundation for the industry optimization of special industrial crop planting in Chengde according to our research.展开更多
The species of main diseases and pests in foxtail millet and their damage status were investigated in 15 survey points in Longhua, Weichang, Chengde, Fengning and Luanping counties, Chengde City from 2015 to 2017. It ...The species of main diseases and pests in foxtail millet and their damage status were investigated in 15 survey points in Longhua, Weichang, Chengde, Fengning and Luanping counties, Chengde City from 2015 to 2017. It was preliminarily cleared that there were 11 species of main diseases and 8 species of pests in continuous cropping millet field. The diseases damaged severely were millet downy mildew and kernel smut, and pests were yellow-legged lema, millet shoot fly and soil insects. The results provided a scientific basis for green control of millet pests and diseases and safe production in Chengde area.展开更多
Landsat TM/OLI images of the built-up areas in Chengde City(Shuangqiao District and Shuangluan District) in 2000,2009 and 2014 were adopted,Support Vector Machine(SVM) was applied to classify the images automatically,...Landsat TM/OLI images of the built-up areas in Chengde City(Shuangqiao District and Shuangluan District) in 2000,2009 and 2014 were adopted,Support Vector Machine(SVM) was applied to classify the images automatically,land use/cover map of the study area was obtained after precision test.Through analyzing the land use types in the study area and also applying transfer matrix to monitor the changes,the results showed that human activities and urbanization in the past 14 years have brought the increasing tendency of construction land,and the negative growth of arable land,forest and shrubbery land.It is urgent to adopt corresponding measures to maintain the coverage of forest and shrubbery land in the built-up area of Chengde City,so as to reduce the impact of human activities and improve urban ecological environment.展开更多
[Objectives]To study the optimum sowing density of quinoa in Chengde region.[Methods]Yanli No.2 cultivated by Institute of Millet Crops,Hebei Academy of Agriculture and Forestry Sciences was taken as test material.In ...[Objectives]To study the optimum sowing density of quinoa in Chengde region.[Methods]Yanli No.2 cultivated by Institute of Millet Crops,Hebei Academy of Agriculture and Forestry Sciences was taken as test material.In Chengde region,single-factor density test design was used to study the effects of sowing on agronomic characters and yield of quinoa.[Results]Quinoa had the highest comprehensive yield when row spacing was 30 cm and plant spacing was 25 cm.[Conclusions]The research could provide theoretical basis for quinoa planting in Chengde region.展开更多
[ Objective] The research aimed to analyze variation rule of the precipitation series in Chengde City in recent 58 years. [Method] Mexi- can hat wavelet was used to analyze multi-scale characteristics of the monthly p...[ Objective] The research aimed to analyze variation rule of the precipitation series in Chengde City in recent 58 years. [Method] Mexi- can hat wavelet was used to analyze multi-scale characteristics of the monthly precipitation data in Chengde from 1951 to 2008. We revealed multi- time-scale complex structure of the precipitation change in Chengde, analyzed change cycles and mutation points of the precipitation series under different time scales, and identified primary period in each series. [ Result]There were high/low value centers of the precipitation under interdec- adal scale (more than 10 years). Under interannual scale (below 10 years), oscillation was complex and variable, but 4-year scale had obvious high-frequency oscillation. Wavelet variance analysis verified existence of the 4-year precipitation cycle, and M - K test also confirmed conclusions of the wavelet analysis. [ Conclusion] We could judge from alternating wet and dry conditions that the wet year decreased significantly, and the cur- rent Drecioitation was still less than normal.展开更多
Holiday Tourism Circle of Beijing (HTCB) is one of the nine key regions of Chinese tourism industry in the period of the 11th Five-Year Project. According to Tourist Marginal Utility Theory, Time-Distance Method is us...Holiday Tourism Circle of Beijing (HTCB) is one of the nine key regions of Chinese tourism industry in the period of the 11th Five-Year Project. According to Tourist Marginal Utility Theory, Time-Distance Method is used to define HTCB in this paper. Chengde City, famous for its cultural tourism, is regard as one of the regions in Holiday Tourism Circle of Beijing. And this geographical advantage, in the context of the boom of tourism in China, is featured by the changes of tourist product structure and development model. In this paper, the influence upon Chengde tourism spatial structure has been discussed from tourist market, location and transportation. Chengde tourism spatial structure has been rebuilt with particular references to the factors of tourism destination district, tourist area, nodes, routes, and origin markets. In this paper, Chengde will develop tourism industry with the central heritage area as the center and northern forest and pasture area and southern mountain and lake area as the two wings.展开更多
From July 26 to 30,the 11th Panchen Erdeni Choskyi Gyalpo paid a visit to Chengde in Hebei Province for his religion activities. He respectively visited the Summer Resort,Puning Monastery, Anyuan Monastery,Xumi Fushou...From July 26 to 30,the 11th Panchen Erdeni Choskyi Gyalpo paid a visit to Chengde in Hebei Province for his religion activities. He respectively visited the Summer Resort,Puning Monastery, Anyuan Monastery,Xumi Fushou Monastery,and Putuo Zongsheng Monastery and paid his homage to Buddha keeping in those monasteries.In Puning Monastery(Monastery of universal peace),展开更多
The selection of important factors in machine learning-based susceptibility assessments is crucial to obtain reliable susceptibility results.In this study,metaheuristic optimization and feature selection techniques we...The selection of important factors in machine learning-based susceptibility assessments is crucial to obtain reliable susceptibility results.In this study,metaheuristic optimization and feature selection techniques were applied to identify the most important input parameters for mapping debris flow susceptibility in the southern mountain area of Chengde City in Hebei Province,China,by using machine learning algorithms.In total,133 historical debris flow records and 16 related factors were selected.The support vector machine(SVM)was first used as the base classifier,and then a hybrid model was introduced by a two-step process.First,the particle swarm optimization(PSO)algorithm was employed to select the SVM model hyperparameters.Second,two feature selection algorithms,namely principal component analysis(PCA)and PSO,were integrated into the PSO-based SVM model,which generated the PCA-PSO-SVM and FS-PSO-SVM models,respectively.Three statistical metrics(accuracy,recall,and specificity)and the area under the receiver operating characteristic curve(AUC)were employed to evaluate and validate the performance of the models.The results indicated that the feature selection-based models exhibited the best performance,followed by the PSO-based SVM and SVM models.Moreover,the performance of the FS-PSO-SVM model was better than that of the PCA-PSO-SVM model,showing the highest AUC,accuracy,recall,and specificity values in both the training and testing processes.It was found that the selection of optimal features is crucial to improving the reliability of debris flow susceptibility assessment results.Moreover,the PSO algorithm was found to be not only an effective tool for hyperparameter optimization,but also a useful feature selection algorithm to improve prediction accuracies of debris flow susceptibility by using machine learning algorithms.The high and very high debris flow susceptibility zone appropriately covers 38.01%of the study area,where debris flow may occur under intensive human activities and heavy rainfall events.展开更多
Traditionally the space group of orthopyroxenes is catalogued into Pbca.Nevertheless,in 1974,Smyth found out that the bronzite from one lunar rock is of P2<sub>1</sub>ca based on thepresence of the 0 kl di...Traditionally the space group of orthopyroxenes is catalogued into Pbca.Nevertheless,in 1974,Smyth found out that the bronzite from one lunar rock is of P2<sub>1</sub>ca based on thepresence of the 0 kl diffractions with k-odd.Sequently it was reported that the ortho-pyroxenes from certain meteorites and a lunar soil are of P2<sub>1</sub>ca.Some展开更多
Chengde Mountain Resort was the summer residence of emperors dur- ing the Qing Dynasty (1644-1911). Construction of the resort started in 1703, and lasted for 87 years. Chengde City in
When the capital starts to heat up,many,like the imperial family of old times,dash for the cooler climes of Chengde,with its royal gardens and clff-hugging temples,Across the world and throughout history kings and emp...When the capital starts to heat up,many,like the imperial family of old times,dash for the cooler climes of Chengde,with its royal gardens and clff-hugging temples,Across the world and throughout history kings and emperors have sought to escape the stress and noise of their capitals.The French kings escaped to Versailles,the German Kaisers to Potsdam,and the British Kings toWindsor.The Manchu emperors of the Qing Dynasty(1644-1911)were no different,and so when faced with the abrasive summer heat in Beijing,they retired to the cool tranquility of Chengde.The city has been home to the world's largest royal garden,part of the royal summer resort since the reign of Emperor Kangxi(1662-1722).展开更多
Lisiguangite, CuPtBiS3, is a new mineral species discovered in a PEG-bearing, Co-Cu sulfide vein in garnet pyroxenite of the Yanshan Mountains, Chengde Prefecture, Hebei Province, China. It is associated with chalcopy...Lisiguangite, CuPtBiS3, is a new mineral species discovered in a PEG-bearing, Co-Cu sulfide vein in garnet pyroxenite of the Yanshan Mountains, Chengde Prefecture, Hebei Province, China. It is associated with chalcopyrite and bornite, galena, minor pyrite, carrolite, molybdenite and the platinum-group minerals daomanite (CuPtAsS2), Co-bearing malanite (Cu(Pt, Co)2S4) sperrylite, moncheite, cooperite and malyshevite (CuPdBiS3), rare damiaoite (Pt2In3) and yixunite (Pt3In). Lisiguangite occurs as idiomorphic crystals, tabular or lamellae (010) and elongated [100] or as aggregates, up to 2 mm long and 0.5 mm wide. The mineral is opaque, has lead-gray color, black streak and metallic luster. The mineral is non-fluorescent. The observed morphology displays the following forms: pinacoids {100}, {010}, {001}, and prism [110}. No twining is observed. The a:b:c ratio, calculated from unit-cell parameters, is 0.6010:1:0.3836. Cleavage: {010} perfect, {001} distinct, {100} may be visible. H Mohs: 2 1/2; VHN25=46.7-49.8 (mean 48.3) kg/mm^2. Tenacity: brittle. Lisiguangite is bright white with a yellowish tint. In reflected light it shows neither internal reflections nor bireflectance or pleochroism. It has weak to moderate anisotropy (blue-greenish to brownish) and parallel-axial extinction. The reflectance values in air (and in oil) for R3, R4 and (^imR3, ^imR4), at the standard Commission on Ore Mineralogy wavelengths are: 37.5, 35.7 (23.4, 22.3) at 470nm; 38.6, 36.5 (23.6, 22.6) at 546nm; 39.4, 37.5 (23.6, 22.7) at 589 nm and 40.3, 38.2 (23.7, 22.9) at 650 nm. The average of eight electron-microprobe analyses: Cu 12.98, Pt 30.04, Pd 2.69, Bi 37.65 and S 17.55, totaling 100.91%, corresponding to Cu1.10(Pt0.83, Pd0.14)∑0.97Bi0.97S2.96 based on six atoms apfu. The ideal formula is CuPtBiS3. The mineral is orthorhombic. Space group: P212121, a=7.7152(15)A, b=12.838(3)A, c=4.9248(10)A, V=487.80(17)A^3, Z=4. The six strongest lines in the X-ray powder-diffraction pattern [d in A(l) (h k l) are 6.40(30)(020), 3.24(80)(031), 3.03(100)(201), 2.27(40)(051), 2.14(50)(250), 1.865(60)(232).展开更多
Geochemical differentiation of soils has a series of consequences on plant and places pressure on the ecological environment.The quantitative evaluation of element migration in the Earth’s critical zone is a challeng...Geochemical differentiation of soils has a series of consequences on plant and places pressure on the ecological environment.The quantitative evaluation of element migration in the Earth’s critical zone is a challenging task.In this study,two demonstration study areas of Scutellaria baicalensis Georgi were selected,and multiple chemical weathering indexes,chemical loss fraction,mass migration coefficients and biological enrichment coefficient method were used to assess the ecological and geochemical suitability.The results show that for the element of Fe,Zn,Se,Cu,Co,Ni,Mo and Ge,the degree of weathering and soil maturation,were greater in the rhyolitic tuff area than in the Plagioclase gneiss area.In both research sites,the heavy metal level of samples in Scutellaria baicalensis Georgi did not exceed the standard limits.The plagioclase gneiss region’s surface soil environment was more alkaline,and the content of soil organic matter was lower,resulting in a higher bioenrichment intensity of Ge,Co,Cu,and Se elements in Scutellaria baicalensis Georgi than in the rhyolite-tuff area.The elements of Cd,Nb,Mo,Pb and As are considerably enriched in the soil of the plagioclase gneiss area but lost by leaching in the soil of the rhyolite tuff area,which is connected to the interplay of elemental abundance and human impact in the parent materials.This study provides a good example of how to assess growth suitability of Chinese medicinal materials in the Earth’s critical zone.展开更多
Pulmonary function in winter time in 1,343 school children aged 10-13 years was measured in four cities located in northern and southern part of China. The results showed that FVC, FEVl, PEF, V75, V50 and V25 in child...Pulmonary function in winter time in 1,343 school children aged 10-13 years was measured in four cities located in northern and southern part of China. The results showed that FVC, FEVl, PEF, V75, V50 and V25 in children living in homes with coal stoves were decreased by 1.5-10.7% compared with children living in homes with gas or LPG stoves in Chengde and Shanghai. In contrast to this, no significant difference in pulmonary function was found in Shenyang and Wuhan. It suggested that this phenomenon was related to indoor air pollution, and partly related to passive smoking or outdoor air pollution.展开更多
文摘Based on the introduction about the gardening conception,layout and method of Chengde Imperial Summer Resort,this study analyzed the eco-consciousness in the gardening and the landscape benefits,ecological benefits,social benefits and economic benefits it has generated.
基金Supported by Science and Technology Planning Project of Hebei Province (09276710D)Project of Hebei Academy of Sciences (10113,10927)Key Subject Construction of High Institutions in Hebei Province
文摘[Objective] The aim was to study the willingness to accept compensation and compensation sharing of returning land for farming to forestry in Zhangjiakou and Chengde region.[Method] Based on the investigation of farmers’ willingness to accept ecological compensation in Zhangjiakou and Chengde region,farmers’ willingness to accept compensation was quantized,and the calculation model of sharing rate of ecological compensation was established,finally the sharing rate of ecological compensation was calculated choosing water supply quantity as reference.[Result] Farmers’ willingness to accept compensation in Zhangjiakou and Chengde region was 2 740.5 yuan/(hm2·a),and returned farmland area was 429 700 hm2 in 2008,so the willingness to accept ecological compensation was up to 1.178 billion yuan/a.In addition,the ecological compensation sharing rate of government was 37.60% in Beijing,42.75% in Tianjing and 19.64% in Tangshan,and their ecological compensation funds were 443,504 and 231 million yuan,respectively.[Conclusion] The study could provide important foundation for the establishment of ecological compensation standard and implementation of ecological compensation in Zhangjiakou and Chengde region.
文摘Air pollution history of sulphur and heavy metals since 1800 in Chengde City , north China,was studied by analyzing the concentrations of sulphur and heavy metals in growth rings of Pinus tabulaeformis Carr. Sulphur concentrations in the tree rings of 1910-1920, 1970-1980,and 1980-1990 have increased 1-2 , 3-5 and 10 times respectively as those in the tree ring of 1810-1820 (P<0. 05). This is ascribed to the result of urbanization, especially the appearance and aggravation of industrialization, in the city of Chengde since 1950s. Fe appeared to increase during 1920-1940, possibly due to the opening of Damiao Iron Mine by the Japanese in 1927; Mn increased throughout the whole history, from 4. 1 μg/g(1840- 1850) to 10. 4 μg/g (1980 1990,P <0. 05);Pb did not increase until 1980 but increased sharply during the last 10 years by 560%(P<0. 001). This is caused by the increased number of automobiles in the city. The contents of Cu,Zn, Ni have changed little. The concentrations of sulphur and heavy metals in the tree rings at the beginning of 1800s were the lowest and could be regarded as the background concentrations.We calculated that S, Fe, Pb, Mn, Ni, and Zn in the tree rings have increased 10, 2.4,1.8,1.5,1.0 and 0. 8 times respectively during the past 190 years or so. The results showed that serious environmental pollution, especially air pollution of SO2,has occurred since 1949 when the People's Republic of China was founded.
文摘Chengde City,famous for its cultural sightseeing tourism industry,and is located in China's"Capital Holiday Tourism Circle".This location is advantageous,because of the recent boom in China's national tourism industry.This industry has gone through several structural and development changes with in the past several years.A result of these restructuring patterns is the great changes concerning competitive and cooperative relations among tourism destinations,which have precipitated the decline of the traditional sightseeing pattern. Northern China's"Capital Holiday Tourism Circle"is one of nine key areas within the Chinese tourism industry under development during the Eleventh Five-Year Plan.In the present article the method of"Distance Decline of The Tourist Flow"was used to define the flow of tourists in the Capital Holiday Tourism Circle and its influence upon Chengde's tourism spatial distribution.3 aspects will be discussed:(1)The transformation from sightseeing to leisure markets makes the change possible in Chengde's tourism spatial pattern.(2)The location advantage(adjacent to Beijing and Tianjin) also leads to the change in Chengde tourism spatial pattern.(3)The establishment of freeways also contributes to a great degrees of change. The rapid development of leisure tourism might lead to the change from nucleus model to a diversified one within Chengde's tourism.Specifically,Chengde is developing the tourism industry with the central heritage area as the nucleus and the northern forest, pasture,southern mountain,and rivers as its periphery.
基金S&T Program of Hebei(No.19224205D)the National Natural Science Foundation of China(No.42001027)+1 种基金Research Project of Social Science Development in Hebei Province(20210201377)Natural Science Foundation of Hebei Province(Nos.D2019403115 and D2019403168)。
文摘In order to probe the geochemical relationship between the quality of economic crops and ecological geochemistry,this project studies the chestnut production area of Chengde City,Hebei Province,China.The chemical weathering index,chemical depletion fraction CDF,mass transfer coefficient,and bioconcentration coefficient were used to quantify the characteristics of element migration and accumulation in the BRSPC(Bedrock–Regolith–Soil–Plant Continuum system)system of gneiss formation area and dolomite formation area.The results show that the soil CaO,SiO_(2),Al_(2)O_(3),and Na_(2)O elements in the gneiss construction area are abundant,and the B,Ge,S,and Mo elements are relatively lacking;the soil B,Mo and Ge elements in the dolomite construction area are abundant,and the SiO_(2),Al_(2)O_(3),and Na_(2)O elements are slightly lower;The weathering intensity of gneiss is low-medium,with the relatively high mobility and apparent transformation of Se,B,V,S,Mn,and Mo.The weathering intensity of dolostone is low,with the relatively high mobility and apparent transformation of Na_(2)O,P,and Ni.Chestnut is rich in Cu,Ni,Se,and Ge,walnut has a high content of Mo,and hawthorn is rich in Se and B.The contents of Mn in chestnut are 1–2 times higher in walnut and hawthorn.It lays the theoretical foundation for the industry optimization of special industrial crop planting in Chengde according to our research.
基金Supported by Science and Technology Research and Development Project of Chengde City(201701A152)
文摘The species of main diseases and pests in foxtail millet and their damage status were investigated in 15 survey points in Longhua, Weichang, Chengde, Fengning and Luanping counties, Chengde City from 2015 to 2017. It was preliminarily cleared that there were 11 species of main diseases and 8 species of pests in continuous cropping millet field. The diseases damaged severely were millet downy mildew and kernel smut, and pests were yellow-legged lema, millet shoot fly and soil insects. The results provided a scientific basis for green control of millet pests and diseases and safe production in Chengde area.
基金Sponsored by Program of Hebei Provincial Department of Education(Z2015080)Scientific and Technological Support Program of Chengde City(2015035)Scientific and Technological Research Program of Hebei Normal University for Nationalities(FY201523)
文摘Landsat TM/OLI images of the built-up areas in Chengde City(Shuangqiao District and Shuangluan District) in 2000,2009 and 2014 were adopted,Support Vector Machine(SVM) was applied to classify the images automatically,land use/cover map of the study area was obtained after precision test.Through analyzing the land use types in the study area and also applying transfer matrix to monitor the changes,the results showed that human activities and urbanization in the past 14 years have brought the increasing tendency of construction land,and the negative growth of arable land,forest and shrubbery land.It is urgent to adopt corresponding measures to maintain the coverage of forest and shrubbery land in the built-up area of Chengde City,so as to reduce the impact of human activities and improve urban ecological environment.
基金Supported by Key R&D Projects in Hebei Province(19227527D)Science and Technology Innovation Team Project of Hebei Coarse Grain and Soybean Seed Industry。
文摘[Objectives]To study the optimum sowing density of quinoa in Chengde region.[Methods]Yanli No.2 cultivated by Institute of Millet Crops,Hebei Academy of Agriculture and Forestry Sciences was taken as test material.In Chengde region,single-factor density test design was used to study the effects of sowing on agronomic characters and yield of quinoa.[Results]Quinoa had the highest comprehensive yield when row spacing was 30 cm and plant spacing was 25 cm.[Conclusions]The research could provide theoretical basis for quinoa planting in Chengde region.
基金Supported by Natural Science Research Item of Hebei Higher Institution (Z2009202)
文摘[ Objective] The research aimed to analyze variation rule of the precipitation series in Chengde City in recent 58 years. [Method] Mexi- can hat wavelet was used to analyze multi-scale characteristics of the monthly precipitation data in Chengde from 1951 to 2008. We revealed multi- time-scale complex structure of the precipitation change in Chengde, analyzed change cycles and mutation points of the precipitation series under different time scales, and identified primary period in each series. [ Result]There were high/low value centers of the precipitation under interdec- adal scale (more than 10 years). Under interannual scale (below 10 years), oscillation was complex and variable, but 4-year scale had obvious high-frequency oscillation. Wavelet variance analysis verified existence of the 4-year precipitation cycle, and M - K test also confirmed conclusions of the wavelet analysis. [ Conclusion] We could judge from alternating wet and dry conditions that the wet year decreased significantly, and the cur- rent Drecioitation was still less than normal.
文摘Holiday Tourism Circle of Beijing (HTCB) is one of the nine key regions of Chinese tourism industry in the period of the 11th Five-Year Project. According to Tourist Marginal Utility Theory, Time-Distance Method is used to define HTCB in this paper. Chengde City, famous for its cultural tourism, is regard as one of the regions in Holiday Tourism Circle of Beijing. And this geographical advantage, in the context of the boom of tourism in China, is featured by the changes of tourist product structure and development model. In this paper, the influence upon Chengde tourism spatial structure has been discussed from tourist market, location and transportation. Chengde tourism spatial structure has been rebuilt with particular references to the factors of tourism destination district, tourist area, nodes, routes, and origin markets. In this paper, Chengde will develop tourism industry with the central heritage area as the center and northern forest and pasture area and southern mountain and lake area as the two wings.
文摘From July 26 to 30,the 11th Panchen Erdeni Choskyi Gyalpo paid a visit to Chengde in Hebei Province for his religion activities. He respectively visited the Summer Resort,Puning Monastery, Anyuan Monastery,Xumi Fushou Monastery,and Putuo Zongsheng Monastery and paid his homage to Buddha keeping in those monasteries.In Puning Monastery(Monastery of universal peace),
基金supported by the Second Tibetan Plateau Scientific Expedition and Research Program(Grant no.2019QZKK0904)Natural Science Foundation of Hebei Province(Grant no.D2022403032)S&T Program of Hebei(Grant no.E2021403001).
文摘The selection of important factors in machine learning-based susceptibility assessments is crucial to obtain reliable susceptibility results.In this study,metaheuristic optimization and feature selection techniques were applied to identify the most important input parameters for mapping debris flow susceptibility in the southern mountain area of Chengde City in Hebei Province,China,by using machine learning algorithms.In total,133 historical debris flow records and 16 related factors were selected.The support vector machine(SVM)was first used as the base classifier,and then a hybrid model was introduced by a two-step process.First,the particle swarm optimization(PSO)algorithm was employed to select the SVM model hyperparameters.Second,two feature selection algorithms,namely principal component analysis(PCA)and PSO,were integrated into the PSO-based SVM model,which generated the PCA-PSO-SVM and FS-PSO-SVM models,respectively.Three statistical metrics(accuracy,recall,and specificity)and the area under the receiver operating characteristic curve(AUC)were employed to evaluate and validate the performance of the models.The results indicated that the feature selection-based models exhibited the best performance,followed by the PSO-based SVM and SVM models.Moreover,the performance of the FS-PSO-SVM model was better than that of the PCA-PSO-SVM model,showing the highest AUC,accuracy,recall,and specificity values in both the training and testing processes.It was found that the selection of optimal features is crucial to improving the reliability of debris flow susceptibility assessment results.Moreover,the PSO algorithm was found to be not only an effective tool for hyperparameter optimization,but also a useful feature selection algorithm to improve prediction accuracies of debris flow susceptibility by using machine learning algorithms.The high and very high debris flow susceptibility zone appropriately covers 38.01%of the study area,where debris flow may occur under intensive human activities and heavy rainfall events.
基金Project supported by the National Natural Science Foundation of China.
文摘Traditionally the space group of orthopyroxenes is catalogued into Pbca.Nevertheless,in 1974,Smyth found out that the bronzite from one lunar rock is of P2<sub>1</sub>ca based on thepresence of the 0 kl diffractions with k-odd.Sequently it was reported that the ortho-pyroxenes from certain meteorites and a lunar soil are of P2<sub>1</sub>ca.Some
文摘Chengde Mountain Resort was the summer residence of emperors dur- ing the Qing Dynasty (1644-1911). Construction of the resort started in 1703, and lasted for 87 years. Chengde City in
文摘When the capital starts to heat up,many,like the imperial family of old times,dash for the cooler climes of Chengde,with its royal gardens and clff-hugging temples,Across the world and throughout history kings and emperors have sought to escape the stress and noise of their capitals.The French kings escaped to Versailles,the German Kaisers to Potsdam,and the British Kings toWindsor.The Manchu emperors of the Qing Dynasty(1644-1911)were no different,and so when faced with the abrasive summer heat in Beijing,they retired to the cool tranquility of Chengde.The city has been home to the world's largest royal garden,part of the royal summer resort since the reign of Emperor Kangxi(1662-1722).
文摘Lisiguangite, CuPtBiS3, is a new mineral species discovered in a PEG-bearing, Co-Cu sulfide vein in garnet pyroxenite of the Yanshan Mountains, Chengde Prefecture, Hebei Province, China. It is associated with chalcopyrite and bornite, galena, minor pyrite, carrolite, molybdenite and the platinum-group minerals daomanite (CuPtAsS2), Co-bearing malanite (Cu(Pt, Co)2S4) sperrylite, moncheite, cooperite and malyshevite (CuPdBiS3), rare damiaoite (Pt2In3) and yixunite (Pt3In). Lisiguangite occurs as idiomorphic crystals, tabular or lamellae (010) and elongated [100] or as aggregates, up to 2 mm long and 0.5 mm wide. The mineral is opaque, has lead-gray color, black streak and metallic luster. The mineral is non-fluorescent. The observed morphology displays the following forms: pinacoids {100}, {010}, {001}, and prism [110}. No twining is observed. The a:b:c ratio, calculated from unit-cell parameters, is 0.6010:1:0.3836. Cleavage: {010} perfect, {001} distinct, {100} may be visible. H Mohs: 2 1/2; VHN25=46.7-49.8 (mean 48.3) kg/mm^2. Tenacity: brittle. Lisiguangite is bright white with a yellowish tint. In reflected light it shows neither internal reflections nor bireflectance or pleochroism. It has weak to moderate anisotropy (blue-greenish to brownish) and parallel-axial extinction. The reflectance values in air (and in oil) for R3, R4 and (^imR3, ^imR4), at the standard Commission on Ore Mineralogy wavelengths are: 37.5, 35.7 (23.4, 22.3) at 470nm; 38.6, 36.5 (23.6, 22.6) at 546nm; 39.4, 37.5 (23.6, 22.7) at 589 nm and 40.3, 38.2 (23.7, 22.9) at 650 nm. The average of eight electron-microprobe analyses: Cu 12.98, Pt 30.04, Pd 2.69, Bi 37.65 and S 17.55, totaling 100.91%, corresponding to Cu1.10(Pt0.83, Pd0.14)∑0.97Bi0.97S2.96 based on six atoms apfu. The ideal formula is CuPtBiS3. The mineral is orthorhombic. Space group: P212121, a=7.7152(15)A, b=12.838(3)A, c=4.9248(10)A, V=487.80(17)A^3, Z=4. The six strongest lines in the X-ray powder-diffraction pattern [d in A(l) (h k l) are 6.40(30)(020), 3.24(80)(031), 3.03(100)(201), 2.27(40)(051), 2.14(50)(250), 1.865(60)(232).
基金funded by the China Geological Survey,grant number DD20190822。
文摘Geochemical differentiation of soils has a series of consequences on plant and places pressure on the ecological environment.The quantitative evaluation of element migration in the Earth’s critical zone is a challenging task.In this study,two demonstration study areas of Scutellaria baicalensis Georgi were selected,and multiple chemical weathering indexes,chemical loss fraction,mass migration coefficients and biological enrichment coefficient method were used to assess the ecological and geochemical suitability.The results show that for the element of Fe,Zn,Se,Cu,Co,Ni,Mo and Ge,the degree of weathering and soil maturation,were greater in the rhyolitic tuff area than in the Plagioclase gneiss area.In both research sites,the heavy metal level of samples in Scutellaria baicalensis Georgi did not exceed the standard limits.The plagioclase gneiss region’s surface soil environment was more alkaline,and the content of soil organic matter was lower,resulting in a higher bioenrichment intensity of Ge,Co,Cu,and Se elements in Scutellaria baicalensis Georgi than in the rhyolite-tuff area.The elements of Cd,Nb,Mo,Pb and As are considerably enriched in the soil of the plagioclase gneiss area but lost by leaching in the soil of the rhyolite tuff area,which is connected to the interplay of elemental abundance and human impact in the parent materials.This study provides a good example of how to assess growth suitability of Chinese medicinal materials in the Earth’s critical zone.
文摘Pulmonary function in winter time in 1,343 school children aged 10-13 years was measured in four cities located in northern and southern part of China. The results showed that FVC, FEVl, PEF, V75, V50 and V25 in children living in homes with coal stoves were decreased by 1.5-10.7% compared with children living in homes with gas or LPG stoves in Chengde and Shanghai. In contrast to this, no significant difference in pulmonary function was found in Shenyang and Wuhan. It suggested that this phenomenon was related to indoor air pollution, and partly related to passive smoking or outdoor air pollution.