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Effect of Irrigation on Groundwater Dynamic Change in the Typical Irrigated Area of Qinghai Province 被引量:2
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作者 周鸿文 吕文星 +2 位作者 唐红波 王永峰 申国峰 《Agricultural Science & Technology》 CAS 2016年第7期1718-1722,共5页
Under the influence of the natural and human factors, water table of irri- gated area Changes frequently, but it is mainly affected by irrigation water infiltration replenishment during the irrigation. 5 groundwater o... Under the influence of the natural and human factors, water table of irri- gated area Changes frequently, but it is mainly affected by irrigation water infiltration replenishment during the irrigation. 5 groundwater observation wells were constructed in experimental plot of the Daxia irrigated area to carry out the experiment of the effect of irrigation on groundwater dynamic change in this research. The results showed that the groundwater stage dynarnic change rule of spring and seedling irri- gation stage in the typical plot was fit to the hydrological geology condition of grade- I terrace of Huangshui river valley. On the whole, lateral canal water direction formed a line effect. The No. 1 and No. 2 observation well were the closest to the lateral canal, which received more supplies, and the water level was the highest; the No, 3 observation well took the second place; The No. 4 and No. 5 observation well accepted least supplies, and the water level was the lowest. The rangeability of water table of spring irrigation period was significantly higher than that of seedling irrigation period, this is mainly due to the difference value of intake water volume and drainage water volume of spring irrigation phase was significantly higher than the seedling irrigation phase. 展开更多
关键词 Farm irrigation Water table Dynamiq Change typical irrigated area basin in Qinghai Province
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GJB2 mutation spectrum in deaf population in a typical southeastern area of China 被引量:10
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作者 DAI Pu YOU Yi-wen +5 位作者 CUI Jing-hong YU Fei HAN Bing KANG Dong-yang YUAN Hui-jun HAN Dong-yi 《Journal of Otology》 2006年第2期94-98,共5页
Mutations in GJB2 gene are the most frequently found mutations in patients with nonsyndromic hearing impairment. However, the spectrum and prevalence of mutations in this gene vary among different ethnic groups. In Ch... Mutations in GJB2 gene are the most frequently found mutations in patients with nonsyndromic hearing impairment. However, the spectrum and prevalence of mutations in this gene vary among different ethnic groups. In China, 30,000 infants are born with congenital hearing impairment annually. In order to provide appropriate genetic testing and counseling to the families, we investigated the molecular etiology of nonsyndromic deafness in 103 unrelated school children attending Nantong School for the Deaf and Mute in Jiangsu Province, China. The coding exon of the GJB2 gene was PCR amplified and sequenced. Sixty two GJB2 mutant alleles were identified in 35.9% (37/103) of the patients. Twenty five patients carried two pathogenic mutations and 12 patients carried one mutant allele. The 235delC was the most common mutation accounting for 69.4% (43/62) of GJB2 mutant alleles. The GJB2 mutant alleles accounted for 30.1% (62/206) of all chromosomes responsible for nonsyndromic hearing impairment. Testing of the 3 most prevalent deleterious frame shift mutations in this cohort detected 100% of all GJB2 mutant alleles. These results demonstrate that an effective genetic testing of GJB2 gene for patients and families with nonsyndromic hearing impairment is possible. 展开更多
关键词 GJB2 mutation spectrum in deaf population in a typical southeastern area of China GENE area
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Temperature Changes in Typical Karst Area of Guangxi to Global Warming during 1971- 2013
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作者 Zhou Meili Lu Hong +2 位作者 Zhou Xiuhua Chen Sirong Qin Weijian 《Meteorological and Environmental Research》 CAS 2015年第10期5-10,共6页
The spatial and temporal variation characteristics of temperature were analyzed by using climate tendency coefficient, climatic inclination rate and Mann-Kendall catastrophe test,based on the annual and seasonal avera... The spatial and temporal variation characteristics of temperature were analyzed by using climate tendency coefficient, climatic inclination rate and Mann-Kendall catastrophe test,based on the annual and seasonal average temperatures of 28 meteorological stations in Guangxi from 1971 to 2013. Under the global warming,the annual and seasonal average temperatures in typical karst area of Guangxi had an increasing trend. The cli- mate inclination rate of annual average temperature reached a significant level, which was about 0.17 ℃/10 a, and the year of abrupt changes ap- peared in 1996. About seasonal temperature's trend, average temperatures of all the four seasons had an increase trend in the past 43 years, and the significant increase was happened in autumn with the temperature increase rate of 0.28 ℃/10 a, followed by increase rate of average tempera- ture in winter with 0.25 ℃/10 a. A long-term warming tendency was observed by seasonal average temperature from 1971 to 2013, especially dur- ing 2002 - 2013. 展开更多
关键词 Temperature change typical karst area Climate tendency coefficient Mann-Kendall catastrophe test China
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Control Measures of Soil Erosion in a Typical Construction Project Area ( Dina 2 Gas Field)
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作者 Huiming Lv 《Meteorological and Environmental Research》 CAS 2013年第2期53-58,共6页
To treat the relationship between project construction and ecological environment and effectively prevent new soil erosion during the construction, according to the project layout, soil erosion distribution as well as... To treat the relationship between project construction and ecological environment and effectively prevent new soil erosion during the construction, according to the project layout, soil erosion distribution as well as natural and socio-economic conditions, the control measures of newly increased soil erosion along the project were carried out based on site survey and analysis of relevant information. In addition, adhering to the prin- ciple of partition prevention and treatment, some guiding prevention and control measures of the natural zone passed by the project and soil erosion control district were determined, which provided scientific references and technical support for the rational layout of water and soil conservation and ecological restoration measures in Dina 2 gas field. 展开更多
关键词 typical construction project area Dina 2 gas field Ecological environment Soil erosion Control measures China
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Agricultural Land Contract and Management Rights:Transferring Price and Countermeasures in Typical Agricultural Areas of China 被引量:2
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作者 穆松林 张义丰 +1 位作者 王开泳 Dhruba Bijaya G.C. 《Journal of Resources and Ecology》 CSCD 2012年第3期262-268,共7页
Henan is a large agricultural province and one of China’s major grain-producing areas. Agricultural land transfer and large-scale operations will have a profound impact on regional economic development and food secur... Henan is a large agricultural province and one of China’s major grain-producing areas. Agricultural land transfer and large-scale operations will have a profound impact on regional economic development and food security. This is a case study taken in Xiwan village in Qinyang city, Henan. This paper builds a transferring pricing model using land use rights assessment and characteristic correction of land contract and management rights. Results show that the transferring price of land contract and management rights should include the economic price, social price and corrected price. The use of a price model should focus on the distinction of theory and practical application. If there is no change in agricultural project,the actual transferring price should be the sum of the economic price and social security price. If there is a change in agricultural projects,such as cropland into cash crops,the actual transferring price should be the sum of the economic price, social price and corrected price. Because of the complexity of income distribution following the transfer, transferring gains should follow a rational distribution in the outflow side, inflow side, managers and land owner. The government should establish reasonable and orderly contracted management of land circulation transferring and use this to build a land transferring price system. 展开更多
关键词 typical agricultural areas agricultural land contract and management rights transferring price transferring model
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Spatio-temporal Differentiation of Trade-offs and Synergies of Ecosystem Services in Typical Mountain Areas of China 被引量:4
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作者 FENG Yanyun ZHAO Yuluan +2 位作者 YANG Zhimou XUE Chaolang LIU Yan 《Journal of Resources and Ecology》 CSCD 2021年第2期268-279,共12页
Mountain area accounts for a high proportion of the land area in China,and it is the focal area to solve the contradiction of imbalanced regional development,as well as an important source of ecosystem services.Theref... Mountain area accounts for a high proportion of the land area in China,and it is the focal area to solve the contradiction of imbalanced regional development,as well as an important source of ecosystem services.Therefore,this area has been facing long-term pressure and challenges in economic development and ecological protection.In this paper,we selected a rocky desertification mountain area,an active mountain area of new tectonic movement and a typical northern earth-rock mountain area,as Qian-Gui karst Mountain area,Hengduan Mountain area and Taihang Mountain area,as examples to represent three main types of mountain areas.Three representative types of ecosystem services,including NPP(Net Primary Productivity)as a support service,water conservation as a regulation service,and agricultural produce as a supply service,were incorporated into this study.Linear regression,correlation analysis and other methods were then used to investigate the spatial-temporal characteristics of the trade-offs and synergies in each of the three kinds of mountain areas during 1990-2015 in China.The analysis yielded three main conclusions for the three mountainous areas.(1)The agricultural produce supply service decreased relatively,while the support and regulation services of NPP and hydrological regulation increased significantly.(2)There was a synergistic relationship between NPP and the hydrological regulation services in the three mountainous areas.The synergistic relation in Qian-Gui karst Mountain area became enhanced,while those in Hengduan and Taihang Mountain areas became weakened,and the former was weakened to a greater extent.There was a trade-off between NPP,the hydrological regulation service and the agricultural produce supply service among the three mountainous areas.In particular,the trade-off between NPP and the agricultural produce supply service in Qian-Gui karst Mountain area became weaker,while those in Hengduan and Taihang Mountain areas were enhanced,and the latter was enhanced to a greater degree.(3)Significant spatial differentiation was evident in the trade-offs and synergies of ecosystem services among the three mountain areas. 展开更多
关键词 ecosystem services trade-offs SYNERGIES spatial-temporal differentiation typical mountain area
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Application of biologic silicon in modern sedimentary section to reconstruction of phytoplankton changes in the East China Sea and the Huanghai Sea during last 200 years 被引量:3
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作者 YANG Qian SONG Xianli +1 位作者 SUN Yao HUANG Jiansheng 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2012年第2期70-77,共8页
Biomarkers had been widely used to reconstruct phytoplankton productivity, and this method was applied in the East China Sea and the Huanghai Sea (Yellow Sea). In this study, Biologic Silicon (BSi) was used as pro... Biomarkers had been widely used to reconstruct phytoplankton productivity, and this method was applied in the East China Sea and the Huanghai Sea (Yellow Sea). In this study, Biologic Silicon (BSi) was used as productivity proxy to reconstruct productivity change of phytoplankton during last 200 years. The results show that the BSi contents of surficial'sediments were in the range of 0.018%-2.516%, averaging 0.726%, and had a similar variation trend with phytoplankton biomass. The vertical distribution profiles revealed that BSi contents were relatively stable, in accordance with the variations of the contemporary phytoplankton standing crop index. According to the stability analysis of BSi in sediments, BSi was not degradaded for the past two hundred years and remained in sediments steadily. Thus, BSi in sediments had the potential to invert paleoproductivity. To conduct further survey, the linear regression equation between BSi contents and phytoplankton biomass index could be used to calculate the phytoplankton productivity by BSi, so that paleoproduetivity may be reconstructed during last 200 years. 展开更多
关键词 typical sea areas of the East China Sea and the Huanghai Sea sediment BSI productivity reconstruction
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DISTRIBUTIONS AND VARIATIONS OF SURFACE OZONE IN CHANGSHU,YANGTZE DELTA REGION 被引量:1
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作者 颜鹏 王木林 +1 位作者 程红兵 周秀骥 《Acta meteorologica Sinica》 SCIE 2003年第2期205-217,共13页
Through one and half year continuous in-situ measurements,the distributions and variations of surface ozone and its precursors at a typical mixed agricultural and metropolitan area- Changshu,Yangtze Delta region,were ... Through one and half year continuous in-situ measurements,the distributions and variations of surface ozone and its precursors at a typical mixed agricultural and metropolitan area- Changshu,Yangtze Delta region,were studied.The preliminary analysis on the concentration levels and variations of surface ozone indicated the obvious seasonal and diurnal cycles during the experiment.The hourly averaged concentrations of surface ozone were high,in about 17% of total valid hours the surface ozone concentration exceeded 50 ppb,and in 22 days the hourly averaged ozone concentration was greater than 100 ppb.There were about 40% of the days in that the daily maximum 8-hour ozone concentration was greater than 50 ppb.The days with daily maximum 8- hour ozone concentration greater than 80 ppb were about 33 days that accounted for about 8% of the observational days.The variations of 5-day moving averaged ozone concentrations depended both on the weather conditions and on the changes of ozone in background atmosphere. Photochemical process had the significant impacts on ozone productions. 展开更多
关键词 typical mixed agricultural and metropolitan area surface ozone impact on crop growth
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