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Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Research & Exploration in Laboratory is the property of Research & Exploration in Laboratory and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Flooding is one of main disasters affecting agricultural production in China. Its influence on rice is rarely studied in Guizhong District in Guangxi. In this study, we investigated the effect of different flooding duration in different growth on growth and yield component of rice. The experiment was carried out in Nalu Cun of Laibing City, Guangxi, China (109°52' E, 24°4'N). The soil was sandy loam. Sixiang No.1 and Baixiang No.139 both as early and late rice were planted in pots in 2015 and 2016. Flooding of early rice started in different growth stages of tillering, booting and flowering. At each growth stage, flooding lasted for 0 (control), 2, 4, 6, 8 and 10 days, respectively. Because the precipitation during the booting and flowering stages of late rice was small the flooding of late rice was designed at 3 different date in tillering stage. At flooding, the water surface remained 2-3 cm higher than plant height. Flooding duration of late rice was same as that of early rice. During the experiment, the tiller number before and after flooding, the heading stage time and its duration, grain number per panicle, seed setting rate, 1000-grain weight and yield per pot after harvest were determined, and the relationships between yield and yield components were analyzed by path analysis. The results showed that the seedling death rate was less than 7.5% when the flooding duration at the tillering stage was below 2 days, not significantly different from control. As the flooding duration increased to 4-10 days, the death rate increased. When the flooding lasted for more than 6 days the death rate of early rice could reach more than 80% and even all the plants died. The death rate of Sixiang 1 reached 50% after flooding 6 days while it was still smaller than 50% for Baixiang 139 after flooding less than 10 days. The death rate was below 40% for the treatment of flooding at flowering stage. The initial heading stage time of flooding 8 d was postponed than that of control when flooding at different growth stages, and heading duration duration was also prolonged. The yield was not significantly decreased when the flooding at the tillering stage lasted for less than 4 days, but flooding for 6 days could result in the reduction of yield by 80% and flooding for 8-10 days could result in the death of plants. The yield reduction rate of flooding for 2 d at the booting and flowering stages was higher than 50%. The path analysis of yield component showed that the yield was mainly affected by effective panicle number, seed setting rate and 1000-grain weight for the flooding at the tillering stage, by seed setting rate, number of grain per panicle and 1000-grain weight for the flooding at the booting stage, and by effective panicle number and seed setting rate for the flooding at the flowering stage, respectively. The study provides important information for formulating flooding disaster warning system and management methods of dual-rice in Xinan region. [ABSTRACT FROM AUTHOR]

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Grassland animal husbandry and rainfed farming are two pillar industries in Inner Mongolia agriculture, and they are vulnerable to natural disasters, especially drought. Analysis of spatio-temporal distribution of drought characteristics in Inner Mongolia is important for local government to tackle climate change. In order to define the spatiotemporal distribution of drought characteristics and its response to climate change in Inner Mongolia at different time scales, monthly data from 46 meteorological stations for the period 1960-2015 were selected in this study, including monthly sunshine hours, wind speed at 10m height, mean temperature, maximum temperature, minimum temperature, precipitation, relative humidity, station pressure and so on. The standardized precipitation evapotranspiration index (SPEI) was established using precipitation and potential evapotranspiration (ET0) data at different time scales, in which ET0 was calculated by FAO Penman-Monteith equation instead of Thornthwaite formula. In order to find out the drought characteristics, Mann-Kendall test, drought indices, climate tendency rate, empirical orthogonal function (EOF) analysis and rotated empirical orthogonal function (REOF) analysis were carried out on the precipitation, ET0 and SPEI. Considering of the pacific decadal oscillation (PDO), the correlation of SPEI with PDO index in Inner Mongolia was also discussed. The results of this research showed that from the inter-annual changes, it showed a humid trend with an abrupt change in 1976 in Inner Mongolia. On the other hand, from the seasonal perspective, it was getting wet in spring (P<0.05) and winter, and there was a drought trend in summer and autumn. The drought coverage appeared as the features of the local and domain drought at the annual scale, and the intensity of drought were light and moderate mainly. Spatially, the western regions had a humid trend, but it was drier in the eastern part of Inner Mongolia on the contrary. Most regions were getting dry in summer (P<0.05) and autumn, and wet in spring and winter. According to the strength of arid sensitivity in Inner Mongolia, it can be divided into 4 sub-regions: Western region (I sub-region), central region (II sub-region), north district in the northeastern region (III sub-region) and south district in the northeastern region (IV sub-region). Drought in I and II sub-regions was gradually alleviated, III and IV sub-regions showed a trend of getting dry. A 12-month-scale SPEI exhibited positive correlation with PDO index since 1960. When it was negative in PDO index, there was quite dry period in Inner Mongolia, otherwise a humid trend. According to the correlation of PDO index with SPEI, it could further prove that there was a significant positive correlation (P<0.05) between PDO index and SPEI, in other words, pacific decadal oscillation had great positive influence on climate and drought characteristics in Inner Mongolia. The record events of the typical drought duration, scale and intensity in yearbook were basically the same with characteristics of calculated SPEI in this paper, which showed SPEI and drought events had good agreement. SPEI could well reflect typical historical drought events, and it had an indicative effect on drought to some extent in Inner Mongolia. The results of this research could be used in assessing the hydrothermal condition scientifically in Inner Mongolia, and could also provide theoretical basis for forecasting and preventing drought disaster. [ABSTRACT FROM AUTHOR]

Xinjiang is the largest cotton producing area in China accounting for more than 50% of the total cotton production in China. So the accuracy of the prediction of cotton production in Xinjiang is particularly important. Based on calibration and validation of cotton growth model COSIM, in this paper, we used a dynamic prediction model for cotton yield forecast and focused on solving the problem of the unknown climatic data substitution during the prediction period. In the process of prediction, the model read the climatic data day by day. For predicting the growth, development and yield of cotton by the dynamic prediction model, in this study, we substituted the measured climatic data in the recent 50, 30, 20, 10, and 5 years for the unknown climatic data from forecasting day to harvest day, respectively. Meanwhile, the climatic data measured in the year was input into the model before forecasting day. In this way, the cotton yield and development could be predicted day by day. To test the reliability of the method, an experiment with 5 different sowing date (April 10th, April 20th, April 30th, May 10th, May 20th) was designed in 2011 at Wusu, Xinjiang (44°43′ N，84°67′ E). Each treatment was replicated 3 times. The cotton was harvested on September 10th, September 15th, September 21th, September 29th and October 5th, respectively. During the experiment, the growing stage of the cotton was recorded. The leaf area and biomass were determined. These parameter values were input into the COSIM model for cotton lint yield prediction. The model reliability was evaluated by comparing the simulated and measured values of lint yield and growing stages. For the simulation, the climatic data measured in 2011 was used. The results showed that the root mean square error (RMSE) of the cotton growing from emergence to flowering stage was 2.2-5.9 d. The determination coefficient was 0.99. For the lint yields simulations, the RMSE was 165.9 kg/hm2. It indicated that the model was reliable in simulating cotton development and lint yield. Based on experimental results of treatment 1 (sowing date was April 20th), we selected the best substitution one for the unknown climatic data from the 5 schemes (climatic data of the recent 50, 30, 20, 10, and 5 years) and then validated by the results from the other treatments. The results showed that the for the randomly selected 7 predicting time (April 1st, May 1st, June 1st, July 1st, August 1st, September 1st, October 1st), the standard deviation of the measured and predicted lint yield of the 5 schemes from 50 to 5 years' climatic data was 171, 123, 82, 86 and 106 kg/hm2, respectively. The predicting accuracy was above 87% compared with the measured values and above 83% compared with the simulated values for the lint yields. Among them, the accuracy in the predicting time after the sowing date was above 93%. Based on the predicting accuracy and the standard deviation, the best scheme was the 10 years' climatic data substation scheme. The validation of the best scheme using the results from the other treatments showed that predicting accuracy could reach 81.3%-99.6%, indicating the reliability of the best scheme for cotton lint yield prediction. Compared with a single station forecasting, the regional forecasting of cotton yield is more important to national macro-control. In a large region, cotton is not sowing on the same day but during a time period. Therefore, in predicting the regional cotton yield, the effect of sowing time should be taken into consideration. As a case, this study only does the forecast once a month. In practice, the daily dynamic forecast would be realized. [ABSTRACT FROM AUTHOR]

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)