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Zheng S.,Lanzhou University | Wang M.,Lanzhou University | Wang S.,Lanzhou University | Shang K.,Lanzhou University | And 2 more authors.
Proceedings - 2011 4th International Conference on Biomedical Engineering and Informatics, BMEI 2011

The main objective of this paper is to supply scientific basics for preventing and forecasting the prevalence of hand, foot and mouth disease to explore the effect of different meteorological conditions on occurrence of hand, foot and mouth disease in Wuwei City, northwestern China. Here the data about the diseases and weather was collected from 2008-2010, and the correlation analysis, multiple linear regression and exponential curve fitting methods were made. The results showed that 2688 cases of hand, foot and mouth disease were collected from 2008 to 2010, and the annual average incidence was 47.62/100,000. The average prevalence of hand, foot and mouth disease at Liangzhou District, Minqin County, Gulang County and Tianzhu Tibetan Autonomous County were 42.69, 38.52, 65.92 and 49.18 per 100,000 respectively. This disease occurred year-round in Wuwei City, but had a clear seasonal climax. Generally, the incidence increased from April and rose to the first peak in May, Jun, July respectively. The second peak was in September or October every year. Different meteorological factors had different impact on the epidemic of disease in four areas, such as average temperature, relative humidity, atmospheric pressure, rainfall and evaporation capacity. The results of multiple linear regressions indicated that relative humidity and atmospheric pressure were the main influence factors in Liangzhou District, average temperature in Gulang County, atmospheric pressure in Tianzhu County. The incidence of the disease and average sunshine hours showed exponential function relationship in Minqin County. In conclusion, different weather conditions have different impact on the prevalence of hand, foot and mouth disease. A high correlation exists in four areas of Wuwei City between meteorological factors and hand, foot and mouth disease occurrence. And summer and autumn were the important seasons to prevent and control the disease. © 2011 IEEE. Source

Ma Y.-P.,Chinese Academy of Meteorological Sciences | Sun L.-L.,Tongliao Meteorological Bureau | E Y.-H.,Chinese Academy of Meteorological Sciences | Wu W.,Wuwei Meteorological Bureau
Chinese Journal of Applied Ecology

Climate change will significantly affect agricultural production in China. The combination of the integral regression model and the latest climate projection may well assess the impact of future climate change on crop yield. In this paper, the correlation model of maize yield and meteorological factors was firstly established for different provinces in China by using the integral regression method, then the impact of climate change in the next 40 years on China's maize production was evaluated combined the latest climate prediction with the reason being analyzed. The results showed that if the current speeds of maize variety improvement and science and technology development were constant, maize yield in China would be mainly in an increasing trend of reduction with time in the next 40 years in a range generally within 5%. Under A2 climate change scenario, the region with the most reduction of maize yield would be the Northeast except during 2021-2030, and the reduction would be generally in the range of 2.3%-4.2%. Maize yield reduction would be also high in the Northwest, Southwest and middle and lower reaches of Yangtze River after 2031. Under B2 scenario, the reduction of 5.3% in the Northeast in 2031-2040 would be the greatest across all regions. Other regions with considerable maize yield reduction would be mainly in the Northwest and the Southwest. Reduction in maize yield in North China would be small, generally within 2%, under any scenarios, and that in South China would be almost unchanged. The reduction of maize yield in most regions would be greater under A2 scenario than under B2 scenario except for the period of 2021-2030. The effect of the ten day precipitation on maize yield in northern China would be almost positive. However, the effect of ten day average temperature on yield of maize in all regions would be generally negative. The main reason of maize yield reduction was temperature increase in most provinces but precipitation decrease in a few provinces. Assessments of the future change of maize yield in China based on the different methods were not consistent. Further evaluation needs to consider the change of maize variety and scientific and technological progress, and to enhance the reliability of evaluation models. ©, 2015, Editorial Board of Chinese Journal of Applied Ecology. All right reserved. Source

Yang X.L.,Lanzhou Institute of Arid Meteorology CMA | Ding W.K.,Wuwei Meteorological Bureau | Li Y.Y.,Wuwei Meteorological Bureau | Hu J.G.,Wuwei Meteorological Bureau
Shengtai Xuebao/ Acta Ecologica Sinica

Using observation data of monthly mean soil surface temperature, air temperature and annual sunshine hours, evaporation, precipitation, relative humidity, average wind speed from four meteorological stations in Wuwei city of Gansu Province during 1961-2010, the spatial and temporal distribution characteristics of the differences between soil and air temperature (Ts−Ta) were analyzed systematically by trend coefficient method, the main meteorological factors of (Ts−Ta) were also analyzed by correlation coefficient method and standardized regressive coefficient in multi-linear regression. The result showed that spatial distribution of (Ts−Ta) was related to the local factors as vegetation, soil stratum lithology, soil moisture; the maximum value (3.5 ℃) of (Ts−Ta) occurred in central oasis plains, minimum value (2.6 ℃) of (Ts−Ta) occurred in desertification of northern district. Monthly change characteristics of (Ts−Ta) was obvious and consistent relatively, whose variation rate was larger between 4.8 ℃ and −6.8 ℃, showed an obvious peak and trough, larger value occurred in the summer half year whose highest value was in June, smaller value occurred in the winter half year whose lowest value was in December. But seasonal trend was not consistent, which showed an upward trend in spring and summer, and rose in central-north area but decreased in the shallow mountain area in autumn, decreased in winter except northern desert area. Annual change showed overall upward trend, rising velocities of (Ts−Ta) were influenced by altitude and underlying surface, it rose the fastest in Gobi desert area, rapidly in Oasis plain region, and slowly in Qilian Mountains slope. The time series of mean annual (Ts−Ta) existed the quasi periodic variation of 5-7a, through a significant level of reliability α =0.05 (F test), and the mutation happened in 2004. Decadal change was very obvious, which was smaller from 1960's to 1970's and larger from 1980's to 2010's. Both of annual soil temperature and air temperature increased, presented an asymmetric change, annual (Ts−Ta) was positively correlated with soil temperature and air temperature whose direct cause was that the rising trend of soil temperature was more significant than that of air temperature. The variation of seasonal (Ts−Ta) was more closely related to variation of soil temperature, the rising trend of (Ts−Ta) was larger in the season that soil temperature increased significantly. The main influencing factors of (Ts−Ta) were maximum air temperature, evaporation and precipitation. (Ts−Ta) was positively correlated to average maximum soil temperature, average minimum air temperature and sunshine hours, but negatively correlated to evaporation, precipitation, relative humidity and average wind speed. Main influencing factors of (Ts−Ta) were different from different stations, which were maximum surface temperature, precipitation and evaporation in Liangzhou; minimum temperature, evaporation and maximum surface temperature in Minqin; maximum surface temperature, minimum temperature and relative humidity in Gulang; maximum surface temperature, relative humidity and minimum temperature in Yongchang. In the context of climate warming, to study and grasp the change rule and influencing factors of (Ts−Ta) was an essential part of revealing meteorological disaster pregnant environment and assessing regional climate evolution. At the same time, it provided scientific reference for curbing ecological environment deterioration, adjusting agricultural production and optimizing planting structure. © 2015, Ecological Society of China. All rights reserved. Source

Luo Y.,Gansu Agricultural University | Cheng Z.,Gansu Agricultural University | Guo X.,Wuwei Meteorological Bureau
Shengtai Xuebao/ Acta Ecologica Sinica

The potential climate productivity refers to the proper highest biological yield or agricultural yield in per unit area when climatic resources such as the light, heat, and water are fully used while the other conditions such as soil, nutrient, carbon dioxide, and so on are under the most suitable status. Gansu Province is the main dry land farming agricultural region in northwestern China. Because of the low natural productivity, its agricultural production still partly relies on climatic conditions, mainly depending on the environmental factors such as the light, heat and water resources and their changes. It has very important theoretical and practical significance in reasonably using of climatic resources, fully displaying the potential climatic productivity, improving productivity application level, and providing valuable advices for agricultural production to study the potential climatic dynamics and its main influence factors. Based on the temperature and precipitation data in 69 meteorological stations during 1971 to 2007 in Gansu province, the temporal and spatial distribution of the potential temperature productivity, precipitation productivity, and climatic productivity and their dynamics were analyzed using Miami model and Thornthwaite Memorial model. At the same time, the spatial and temporal dynamics characteristics of potential climatic productivity in the recent 40 years were analyzed using the EOF function and the Mann-Kendall statistical method. Also, the driving forces to the dynamics of potential climatic productivity in Gansu province were analyzed. The results showed that the potential temperature productivity was significantly increased while the potential precipitation productivity was slightly decreased in the recent 40 years with their conversion year in 1997and 1994. The mean potential climatic productivity in Hexi Corridor, Gannan Grassland, Middle Gansu Plateau, Eastern Gansu Plateau, Southern Gansu province were 313. 36, 741.72, 763.85, 867.52, 982. 86 kg•hm-2••a-1, respectively. Besides, the potential climatic productivity was obviously increased from 1979 to 1996 with its conversion year in 1997, and the conversion year was 1997 while significantly and continually decreased from 1997 to 2007. The correlation coefficients between the potential climatic productivity and the mean annual precipitation, and between the potential productivity and the mean annual temperature were 0. 94 and 0.04, respectively. Therefore, the precipitation was the key factor to determine the potential climate productivity in Gansu province. The spatial distribution of potential climatic productivity in Gansu province was decreased from southeast to northwest, the minimum and maximum values marked in Dunhuang with 74. 52 kg•hm-2••a-1 and Huixian with 1094.39 kg•hm-2••a-1, respectively, while the mean potential climate productivity of the whole province was 733. 86 kg•hm-2••a-1 According to the average distribution of potential climatic productivity, the maximum value was obtained in Southern Gansu province, followed by Eastern Gansu Plateau, Middle Gansu Plateau, Gannan Grassland and Hexi Corridor in order. furthermore, both temperature and humidity increasing were beneficial to the agricultural production in the whole province with the temperature increasing effect of 5. 51 -25. 34 kg•hm-2••a-1 and the humidity increasing effect of 27. 89 -34.49 kg•hm-2••a-1, and the humidity increasing effect was much more significant, especially having significant promotion to agricultural development in Hexi Corridor. Therefore, the precipitation was the main driving force to influence the potential climate productivity in Gansu province. In addition, the warmer and drier climatic changing trend can aggravate to the reduction of the potential climate productivity. Source

Cao L.,Lanzhou Institute of Arid Meteorology | Wang Q.,Gansu Meteorological Bureau | Deng Z.-Y.,Lanzhou Institute of Arid Meteorology | Guo X.-Q.,Wuwei Meteorological Bureau | Ma X.-X.,Wuwei Meteorological Bureau
Chinese Journal of Applied Ecology

Based on the data of air temperature, precipitation, and millet yield from Ganzhou, Anding, and Xifeng, the representative stations in Hexi moderate arid oasis irrigation area, moderate sub-arid dry area in middle Gansu, and moderate sub-humid dry area in eastern Gansu, respectively, this paper calculated the regional active accumulated temperature of ≥0 °C , ≥ 5 °C , ≥ 10 °C , ≥ 15 °C , and ≥ 20 °C in millet growth period, and the average temperature and precipitation in millet key growth stages. The millet climatic yield was isolated by orthogonal polynomial, and the change characteristics of climate and millet climatic yield as well as the effects of climate change on millet yield were analyzed by statistical methods of linear tendency, cumulative anomaly, and Mann-Kendall. The results showed that warming and drying were the main regional features in the modern climatic change of Gansu. The regional temperature had a significant upward trend since the early 1990s, while the precipitation was significantly reduced from the late 1980s. There were significant correlations between millet yield and climatic factors. The millet yield in dry areas increased with the increasing temperature and precipitation in millet key growth stages, and that in Hexi Corridor area increased with increasing temperature. Warming and drying affected millet yield prominently. The weather fluctuation index of regional millet yield in Xifeng, Anding, and Ganzhou accounted for 73% , 72% , and 54% of real output coefficient variation, respectively, and the percentages increased significantly after warming. Warming was conducive to the increase of millet production, and the annual increment of millet climatic yield in Xifeng, Anding, and Ganzhou after wanning was 30.6, 43.1, and 121.1 kg · hm -2, respectively. Aiming at the warming and drying trend in Gansu Province in the future, the millet planting area in the Province should be further expanded, and the millet planting structure should be adjusted. At the same time, according to the different regional and yearly climatic types, different varieties should be selected, and various planting measures should be taken. Source

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