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Effects of NPY Gene on Total Number of Eggs at 300 Days of Age in Donglan Black-bone Chicken 被引量:1
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作者 Yuying LIAO Junli SUN +3 位作者 Xinwang WEN Yingfei HUANG Bing ZHANG Fengying WEI 《Agricultural Biotechnology》 CAS 2015年第4期23-24,28,共3页
In this study, PCR-RFLP technique was employed to detect the genetic polymorphism of NPY gene and analyze the effects of various genotypes on the total number of eggs at 300 days of age in 135 Donglan black-bone chick... In this study, PCR-RFLP technique was employed to detect the genetic polymorphism of NPY gene and analyze the effects of various genotypes on the total number of eggs at 300 days of age in 135 Donglan black-bone chicken. According to the results, there were three genotypes (AA, AB and BB) of NPYgene in Donglan black-bone chicken group. Different genotypes exhibited significant effects (P 〈 0. 05 ) on the total number of eggs at 300 days of age. The total number of eggs at 300 days of age of AA genotype was significantly higher than that of BB genotype (P 〈 0. 05). Therefore, the polymorphic site of NPY gene could be used as a candidate molecular marker that affects egg laying in Donglan black-bone chicken. 展开更多
关键词 Donglan black-bone chicken NPY gene Total number of eggs at 300 days of age
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Study on Prediction Model of Number of Rainstorm Days in Summer Based on C5.0 Decision Tree Algorithm
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作者 Shi Yimin Chen Weiwei Zhu Yunfeng 《Meteorological and Environmental Research》 CAS 2019年第2期56-60,共5页
Based on the data of daily precipitation in Lianyungang area from 1951 to 2012 and various climate signal data from the National Climate Center website and the NOAA website,a model for predicting whether the number of... Based on the data of daily precipitation in Lianyungang area from 1951 to 2012 and various climate signal data from the National Climate Center website and the NOAA website,a model for predicting whether the number of rainstorm days in summer in Lianyungang area is large was established by the classical C5. 0 decision tree algorithm. The data samples in 48 years( accounting for about 80% of total number of samples)was as the training set of a model,and the training accuracy rate of the model was 95. 83%. The data samples in the remaining 14 years( accounting for about 20% of total number of samples) were used as the test set of the model to test the model,and the test accuracy of the model was 85. 71%. The results showed that the prediction model of number of rainstorm days in summer constructed by C5. 0 algorithm had high accuracy and was easy to explain. Moreover,it is convenient for meteorological staff to use directly. At the same time,this study provides a new idea for short-term climate prediction of number of rainstorm days in summer. 展开更多
关键词 C5. 0 algorithm number of RAINSTORM days PREDICTION model
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Changing Trend and Mutation Analysis of Number of Fog and Haze Days in Baoji City during 1981-2013
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作者 Li Gaiping Zhou Qi Zhai Yaqian 《Meteorological and Environmental Research》 CAS 2016年第4期5-9,共5页
Based on data of number of fog and haze days in Baoji City from 1981 to 2013,the changing trends and mutation of number of fog and haze days in Baoji over the past 33 years were analyzed by using trend coefficient,ten... Based on data of number of fog and haze days in Baoji City from 1981 to 2013,the changing trends and mutation of number of fog and haze days in Baoji over the past 33 years were analyzed by using trend coefficient,tendency rate,linear regression analysis,anomaly percentage,Mann-Kendall mutation test and sliding t test.The results showed that during the 33 years,the number of fog and haze days in Baoji declined by 16.253d/10 a,and there was a cyclical turbulence every 6,15 or 28years.The frequency of fog and haze weather was the highest in winter,followed by spring and autumn,while it was the lowest in summer.According to the anomaly percentage of the number of fog and haze days in 12 months during 1981-2013,the anomaly percentage changed most greatly in July,followed by September,October,April,May,June,August,February and March,but it fluctuated less greatly in January.The number of fog and haze days from 1981 to 2013had obvious mutation trends in a single year and a single season,and mutation types are different. 展开更多
关键词 number of fog and haze days Changing features Mann-Kendall method Sliding t test method Baoji China
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SPATIO-TEMPORAL VARIATION OF SEASONAL EXTREME WET DAYS IN CHINA AND ITS RELATIONSHIP WITH SST ANOMALIES
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作者 汪卫平 杨修群 +3 位作者 谢益军 邹用昌 房佳蓓 谢倩 《Journal of Tropical Meteorology》 SCIE 2012年第4期485-493,共9页
With daily precipitation records at 586 stations in China for 1960-2004, this study investigates the spatio-temporal variation of the number of extreme wet days (NEWD) for each season in China and its relationship wit... With daily precipitation records at 586 stations in China for 1960-2004, this study investigates the spatio-temporal variation of the number of extreme wet days (NEWD) for each season in China and its relationship with SST anomalies and associated atmospheric circulation anomaly patterns, in which a threshold of extreme precipitation for a season and a station is defined as the value of the 90th percentile when the precipitation records for wet days during the season are ranked in an increasing order. Results show that there are significant increases of the NEWD along the Yangtze River valley during winter and summer, in North China during winter, in South China during spring, in Northeast China during winter and spring, and in Northwest China throughout the seasons, while there is a remarkable decrease in North China during summer. Besides the linear trend, the NEWD also exhibits considerable interannual and interdecadal variabilities. After eliminating the linear trend, the NEWD anomalies show distinct seasonal patterns. The NEWD anomalies are characterized by a "dipole" mode with opposite phases between northern and southern China in spring and autumn, a "tri-pole" mode with opposite phases between Yangtze River valley and southern and northern China in summer, and a "monopole" mode with the same phase over most of China in winter. The relationship of the NEWD anomalies in China with the SST anomalies in Indian and Pacific Oceans is found to be mainly dependent on the ENSO, and associated atmospheric circulation anomaly patterns for the ENSO's impact on the NEWD in China are identified. 展开更多
关键词 extreme precipitation number of extreme wet days SST anomaly ENSO
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Impacts of climate change on the yields of leguminous crops in the Guinea Savanna agroecological zone of Ghana
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作者 Enoch YELELIERE Philip ANTWI-AGYEI Frank BAFFOUR-ATA 《Regional Sustainability》 2023年第2期139-149,共11页
The impacts of climate change on crop yields are receiving renewed interest,with focus on cereals and staple crops at the regional and national scales.Yet,the impacts of climate change on the yields of leguminous crop... The impacts of climate change on crop yields are receiving renewed interest,with focus on cereals and staple crops at the regional and national scales.Yet,the impacts of climate change on the yields of leguminous crops in the local context has not been explored.Thus,an in-depth understanding of climate change in the local context may support the design of locally relevant adaptation responses to current and future climate risks.This study examined the impacts of climate variables(annual rainfall,annual average temperature,rainfall indices(rainfall onset,rainfall cessation,and the length of rainy days),and the number of dry days)on the yields of leguminous crops(groundnuts,cowpeas,and soybeans)in the Guinea Savanna agroecological zone of Ghana during the period of 1989-2020.The data were analysed using Mann-Kendall’s trend,Sen’s slope test,correlation analysis,and Multiple Regression Analysis(MRA).The findings revealed that annual rainfall,annual average temperature,rainfall onset,rainfall cessation,and the length of rainy days,and the number of dry days all showed varied impacts on the yields of groundnuts,cowpeas,and soybeans.The trend analysis detected a marginal decrease in the amount of rainfall,rainfall onset,and the number of dry days from 1989 to 2020(P>0.050).Annual average temperature and the length of rainy days substantially varied(P<0.050)from 1989 to 2020,showing an increasing trend.The findings also showed a marked upward trend for the yields of groundnuts,cowpeas,and soybeans during 2005-2020.The climate variables analysed above increased the yields of groundnuts,cowpeas,and soybeans by 49.0%,55.0%,and 69.0%,respectively.The yields of groundnuts,cowpeas,and soybeans fluctuated with the variability of 30.0%,28.0%,and 27.0%from 2005 to 2020,respectively.The three leguminous crops under study demonstrated unpredictable yields due to the variations of annual rainfall,annual average temperature,rainfall onset,rainfall cessation,the length of rainy days,and the number of dry days,which stressed the need for agricultural diversification,changing planting dates,using improved seed variety,and irrigation to respond to climate change.The results of this study implied that climate change considerably impacts crop production in the Guinea Savanna agroecological zone of Ghana,emphasizing the urgency of locally based and farmer-induced adaptation measures for food security and resilient agricultural systems. 展开更多
关键词 Climate change Leguminous crops(groundnuts cowpeas and soybeans) Guinea Savanna Annual average temperature Rainfall indices number of dry days
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Characteristics of Haze Weather and Its Meteorological In-fluencing Factors in Hangzhou
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作者 Yani ZHANG Rui LIU +2 位作者 Yunbiao ZHANG Yongliang HU Weishi AN 《Meteorological and Environmental Research》 CAS 2023年第1期24-28,共5页
Based on the observation data of the annual number of haze days,rainy days,fog days and gale days,sunshine hours,relative humidity and maximum wind speed at Hangzhou station from 1960 to 2021,the variation characteris... Based on the observation data of the annual number of haze days,rainy days,fog days and gale days,sunshine hours,relative humidity and maximum wind speed at Hangzhou station from 1960 to 2021,the variation characteristics of haze days and meteorological influencing factors were studied by mathematical statistical methods such as Mann-Kendall nonparametric test,sliding T test,wavelet analysis and Pearson correlation two-tailed test.The results show that the annual number of haze days generally showed an upward trend,and the climate tendency rate was 20 d/a;there was a sudden change around 2001,and it changed from stable to rapid growth;the number of haze days was the largest in spring and winter,followed by autumn,while it was the smallest in summer.The annual number of haze days had a strongly significant period of 40 a and a mesoscale variation period of 13 a.The number of haze days was negatively correlated with the number of rainy days,fog days and gale days,sunshine hours,relative humidity and maximum wind speed,which passed the 0.05 significance test.In recent 60 years,the number of rainy days and gale days,relative humidity,and maximum wind speed in Hangzhou have decreased,resulting in the weakening of atmospheric wet deposition capacity and power transmission conditions,which provided favorable meteorological conditions for the increase of haze weather. 展开更多
关键词 number of haze days Wavelet analysis Influencing factor Correlation
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Relationship between Regional Rainstorm Index and Flood Disaster Ratio of Crop 被引量:8
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作者 姜会飞 廖树华 +1 位作者 潘学标 候双双 《Agricultural Science & Technology》 CAS 2011年第3期429-434,共6页
According to the daily precipitation data in Beijing area from 1985 to 2008,rainstorm weather index (10.4-38.8 mm) and climate index (daily precipitation ≥27.5 mm) in Beijing area were obtained by using the deter... According to the daily precipitation data in Beijing area from 1985 to 2008,rainstorm weather index (10.4-38.8 mm) and climate index (daily precipitation ≥27.5 mm) in Beijing area were obtained by using the determination method of extreme climate event index recommended by IPCC. Based on rainstorm weather index,rainstorm climate index and national rainstorm standard,the number of rainstorm days and rainfall amount in past years were calculated,and the correlation of annual number of rainy days,rainstorm days,precipitation and rainstorm amount with the flood disaster ratio of crop was analyzed,and the results showed that annual number of rainy days and rainstorm days couldn't reflect flood disaster ratio of crop truly,while annual precipitation and rainstorm amount had obvious linear positive correlation with the flood disaster ratio of crop. In addition,the correlation degree between rainstorm amount calculated by regional climate index and flood disaster ratio of crop was the highest,so it was suggested that rainstorm amount calculated by regional rainstorm climate index could be used to predict and evaluate flood disaster. 展开更多
关键词 RAINSTORM Rainstorm index number of rainstorm days Rainstorm amount Flood disaster
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Spatial Characteristics of Temperature Indices of Climate Change in China
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作者 王大钧 胡春丽 徐智鑫 《Meteorological and Environmental Research》 CAS 2010年第8期52-54,61,共4页
Based on the temperature indices established by expert group on the detection,monitoring and indices of climate change,spatial characteristics of temperature indices from 278 meteorological stations in China during 19... Based on the temperature indices established by expert group on the detection,monitoring and indices of climate change,spatial characteristics of temperature indices from 278 meteorological stations in China during 1961-2008 were studied.The results showed that day number of freezing point went down gradually from northwest to southeast,as well as the most regions of China.Day number of summer was mostly over 50 d in China and over 100 d in Eastern China except for the most part of Northeast China,while there was an increase trend in the most regions of China.Growth period was generally above 150 d in China and increased with the decrease of latitude from north to south,while the trend coefficient of growth period in 236 stations was positive. 展开更多
关键词 Indices of climate change day number of freezing point day number of summer Growth period China
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<i>Bradyrhizobium japonicum</i>Inoculation and Phosphorus Supplementation on Growth and Chlorophyll Accumulation in Soybean (<i>Glycine max</i>L.) 被引量:2
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作者 Eutropia V. Tairo Patrick A. Ndakidemi 《American Journal of Plant Sciences》 2013年第12期2281-2289,共9页
A field and glasshouse experiment was conducted to study the effect of B. japonicum inoculation and phosphorus supplementation on growth and leaf chlorophyll content in soybean. The treatments consisted of B. japonicu... A field and glasshouse experiment was conducted to study the effect of B. japonicum inoculation and phosphorus supplementation on growth and leaf chlorophyll content in soybean. The treatments consisted of B. japonicum inoculation (with & without), phosphorus supplementation at the levels of 0, 20, 40 and 80 kgP·ha-1. Both treatments were replicated four times in a split plot design. The following parameters were measured: plant height (cm), number leaves per plant, number of days to 50% flowering, number of days to 50% pod formation, stem girth and leaf area (LA). Results showed that inoculation with B. japonicum significantly increased plant height, number of leaves, leaf chlorophyll content, stem girth, leaf area (LA) and leaf area index (LAI). However, Phosphorus supplementation had significant effects in some parameters measured. The use of effective strain of B. japonicum and phosphorus supplementation was an efficient way of enhancing the growth of soybean. 展开更多
关键词 days to 50% Flowering days to 50% Pod Formation Legumes PLANT Height LEAF Area (LA) LEAF Area Index (LAI) number of Leaves per PLANT Stem GIRTH
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Closer Approximation to Optimize Solar Panels Performance with Cleaning Cycle: A Follow-Up 被引量:2
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作者 Rijan Karkee Sumit Khadka 《Open Journal of Energy Efficiency》 2019年第4期166-178,共13页
The performance of solar panels significantly degrades due to dust accumulation but cleaning too frequently will severely impact the financial benefits of the installation of solar panels. This paper assumes a realist... The performance of solar panels significantly degrades due to dust accumulation but cleaning too frequently will severely impact the financial benefits of the installation of solar panels. This paper assumes a realistic linear model for accumulation of dust on the solar panels and the resulting hourly average of absolute loss of efficiency in solar panels. This model accurately depicts the fact that energy production by solar panels occurs during sunshine hours only and also accounts for the degradation in the efficiency of solar panels due to dust accumulation throughout the entire day. Based on this, the optimal number of days for maximum financial profit and the critical number of days (above which there is no profit in installing solar panels) have been estimated. Furthermore, we have suggested a formalism to help estimate the finances for self-cleaning technology for PV system and also for calculating the minimum payback period for installing solar panels with the financial cost of the cleaning cycles properly considered. This research could be motivation for companies in developing self-cleaning mechanism for PV system. 展开更多
关键词 DUST ACCUMULATION Optimal and Critical number of days for Cleaning Cycles Payback Period SELF-CLEANING System
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Climatic Characteristics of Rainstorm during the Flood Season in Shandong Province from 1961 to 2012
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作者 Li Rui Yin Chengmei Meng Lingwang 《Meteorological and Environmental Research》 CAS 2017年第5期37-42,48,共7页
Based on daily precipitation data at 35 meteorological observation stations during the flood season in Shandong Province from 1961 to2012,the spatial and temporal variation characteristics of number of rainstorm days ... Based on daily precipitation data at 35 meteorological observation stations during the flood season in Shandong Province from 1961 to2012,the spatial and temporal variation characteristics of number of rainstorm days and rainstorm intensity were analyzed by conventional statistical methods. The results show that the number of rainstorm days and rainstorm intensity during the flood season in Shandong showed a decreasing trend from 1961 to 2012,but the decreases were not statistically significant at the 0. 05 level. Annual average number of rainstorm days during the flood season in Shandong over the past 52 years was 2.2d and had the changing periods of 3. 4 and quasi-8 a; the annual average rainstorm intensity was 67. 8 mm/d and had the changing periods of 2. 3,3. 3,6. 9 and quasi-12. 0 a. From 1961 to 2012,there was no abrupt climatic change in the number of rainstorm days and rainstorm intensity during the flood season in Shandong,and the number of rainstorm days and rainstorm intensity during the flood season in Shandong reduced from the middle and late 1970 s to the late 1980 s. The annual average number of rainstorm days and rainstorm intensity during the flood season in Shandong from 1961 to 2012 rose gradually from the northwest to the southeast. Rainstorm( continuous rainstorm) during the flood season appeared frequently,and rainstorm intensity was high in the south of Shandong Province,the south and east of Shandong Peninsula. 展开更多
关键词 Shandong Province Flood SEASON number of RAINSTORM days RAINSTORM intensity CLIMATIC characteristics
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IMPACT OF ATMOSPHERIC LOW-FREQUENCY OSCILLATION ON THE IMMIGRATION OF NILAPARVATA LUGENS(STL) IN HUNAN AND JIANGXI PROVINCES
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作者 SUN Si-si BAO Yun-xuan +2 位作者 ZHENG Teng-fei LU Ming-hong XIE Xiao-jin 《Journal of Tropical Meteorology》 SCIE 2018年第2期209-219,共11页
Various features of the atmospheric environment affect the number of migratory insects, besides their initial population. However, little is known about the impact of atmospheric low-frequency oscillation(10 to 90 day... Various features of the atmospheric environment affect the number of migratory insects, besides their initial population. However, little is known about the impact of atmospheric low-frequency oscillation(10 to 90 days) on insect migration. A case study was conducted to ascertain the influence of low-frequency atmospheric oscillation on the immigration of brown planthopper, Nilaparvata lugens(Stl), in Hunan and Jiangxi provinces. The results showed the following:(1) The number of immigrating N. lugens from April to June of 2007 through 2016 mainly exhibited a periodic oscillation of 10 to 20 days.(2) The 10-20 d low-frequency number of immigrating N. lugens was significantly correlated with a low-frequency wind field and a geopotential height field at 850 h Pa.(3) During the peak phase of immigration, southwest or south winds served as a driving force and carried N. lugens populations northward, and when in the back of the trough and the front of the ridge, the downward airflow created a favorable condition for N. lugens to land in the study area. In conclusion, the northward migration of N. lugens was influenced by a low-frequency atmospheric circulation based on the analysis of dynamics. This study was the first research connecting atmospheric low-frequency oscillation to insect migration. 展开更多
关键词 atmospheric low-frequency oscillation Nilaparvata lugens (St/il) immigrating number cycle of 10-20 days atmospheric circulation
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Charging states on atmospheric aerosol particles affected by meteorological conditions
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作者 Yuanping He Zhaolin Gu +4 位作者 Weizhen Lu Liyuan Zhang Daizhou Zhang Tomoaki Okuda Chuck Wah Yu 《Particuology》 SCIE EI CAS CSCD 2020年第5期1-9,共9页
Previous studies on haze formation focused mainly on the various chemical components in aerosol particles and their physicochemical effects on particle behaviour(e.g.,generation,growth,and agglomeration).This paper de... Previous studies on haze formation focused mainly on the various chemical components in aerosol particles and their physicochemical effects on particle behaviour(e.g.,generation,growth,and agglomeration).This paper describes the measurement of the charging state on atmospheric aerosol particles,which could be affected by meteorological conditions.A series of experiments on particle charging state and meteorological factors was undertaken on the roof of the west 4th building on the Qujiang Campus at Xi'an Jiaotong University(China).Measurements were conducted approximately 20 m above ground level,Our results showed that most atmospheric particles carried net negative or positive charge and that the electric charge on the particles varied diurnally and seasonally.The average amount of charge on particles was higher in winter than in summer.The number concentration of charged particles was higher during the day than overnight.Obvious difference in the average charge of aerosol particles was found between sand-dust days and haze days.A strong relationship was found between the PM2.s concentration,charge amount on particles,and humidity.Our findings show that particle formation and growth could partly be attributed to variation in particle charging state,which is related to meteorological conditions including atmospheric humidity. 展开更多
关键词 Aerosol particles Atmospheric humidity Charging state Haze day Physicochemical effect sand-dust day
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