With the improvement of agricultural mechanization equipment levels, the mechanized wheat harvesting level has been above 80% and the rate of wheat straw returned has increased significantly in the main wheat producti...With the improvement of agricultural mechanization equipment levels, the mechanized wheat harvesting level has been above 80% and the rate of wheat straw returned has increased significantly in the main wheat production of wheat of northern countryside in China. Chinese government popularized the beneficial agronomic measures in the process of wheat straw returned field by mechanization. The agronomic measure was reducing the wheat straw stubble height(WSSH) not more than 20 cm.However, local government didn't apply and disseminate the measure, because in practice the cost of fuel consumption was high, and the operation time of harvesting was longer than ever. The machinery operators and farmers needed to support extra fuel cost and time if they took government's advice. In fact, the objective subsidy policy of fuel cost on reducing WSSH was not been formulated by all levels of government. Therefore, the set of agronomic measure couldn't be popularized in main wheat production area of North China. Our research addressed to master the changing feature of fuel cost and mechanical efficiency,seeking suitable subsidy standard, providing some useful and constructive suggestions to improve subsidy policy of fuel consumption cost for national government department. The study carried out the tracking experiments of the operation efficiency and fuel costs of farm harvester in the situation of different WSSH in 2010 in Xushui District of Hebei Province. In conclusion, the operation time of harvesting decline and machinery fuel consumption cost increased along with the decreasing of WSSH. First for the older harvester, the operation efficiency would decline by 18.7% when the WSSH changed from 20 cm to 10 cm, the cost would increase 4.7%, exact cost was 152.2CNY per hectare. For the new harvester, the operation efficiency would decline by 39.9% when the WSSH changed from 20 cm to 15 cm, the cost would increase 4.6%, exact cost was 368.4CNY per hectare. We provided about 375 CNY per hectare to the mechanical operators and farmer who attended this project, and they were willing to accept the subsidies. We also put forwards some policy suggestions on promoting agronomic measures of reducing WSSH including strengthen the construction of agricultural machinery service system, practise a special fuel consumption subsidies of agricultural machinery and open up new paths for combine sales and circulation.展开更多
Pre-harvest yield prediction of ratoon rice is critical for guiding crop interventions in precision agriculture.However,the unique agronomic practice(i.e.,varied stubble height treatment)in rice ratooning could lead t...Pre-harvest yield prediction of ratoon rice is critical for guiding crop interventions in precision agriculture.However,the unique agronomic practice(i.e.,varied stubble height treatment)in rice ratooning could lead to inconsistent rice phenology,which had a significant impact on yield prediction of ratoon rice.Multi-temporal unmanned aerial vehicle(UAV)-based remote sensing can likely monitor ratoon rice productivity and reflect maximum yield potential across growing seasons for improving the yield prediction compared with previous methods.Thus,in this study,we explored the performance of combination of agronomic practice information(API)and single-phase,multi-spectral features[vegetation indices(VIs)and texture(Tex)features]in predicting ratoon rice yield,and developed a new UAV-based method to retrieve yield formation process by using multi-temporal features which were effective in improving yield forecasting accuracy of ratoon rice.The results showed that the integrated use of VIs,Tex and API(VIs&Tex+API)improved the accuracy of yield prediction than single-phase UAV imagery-based feature,with the panicle initiation stage being the best period for yield prediction(R^(2) as 0.732,RMSE as 0.406,RRMSE as 0.101).More importantly,compared with previous multi-temporal UAV-based methods,our proposed multi-temporal method(multi-temporal model VIs&Tex:R^(2) as 0.795,RMSE as 0.298,RRMSE as 0.072)can increase R^(2) by 0.020-0.111 and decrease RMSE by 0.020-0.080 in crop yield forecasting.This study provides an effective method for accurate pre-harvest yield prediction of ratoon rice in precision agriculture,which is of great significance to take timely means for ensuring ratoon rice production and food security.展开更多
This study attempted to clarify the carrying-over effect of different nitrogen treatments applied to the main crop on the crop population growth and yield formation of ratoon rice under mechanized cultivation in South...This study attempted to clarify the carrying-over effect of different nitrogen treatments applied to the main crop on the crop population growth and yield formation of ratoon rice under mechanized cultivation in Southeast China.Based on the constant total nitrogen application amounts(225.00 kg ha;)in the main crop,an experiment with different ratios of basal and topdressing nitrogen fertilizer(the ratio of basal fertilizer:primary tillering fertilizer:secondary tillering fertilizer:booting fertilizer at 3:1:2:4(N1),3:2:1:4(N2),3:3:0:4(N3),and 4:3:0:3(N4),respectively,and a control without nitrogen treatment(N0))was set up across two consecutive years in field using hybrid rice variety Yongyou 1540 as the test materials.The results showed that the total tiller number and effective tillering percentage increased in the main crop under the N1 treatment,more nitrogen fertilizer applied in late growth stage of the main crop,and its effective tillering percentage of the main crop was the highest at up to 70.18%,which was 9.15%higher than that of conventional fertilization treatment(N4),more nitrogen fertilizer applied in early growth stage of the main crop.The same tendency was observed in leaf area index(LAI)value of the main crop and its subsequent ratoon rice,which were 16.52 and 29.87%higher,respectively,in the N1 treatment than that in the N4 treatment at the full heading stage.The same was true in the case of the transport rates of stem and sheath dry mater and the canopy light interception rates in both the main and its ratoon crops.The transport rate of stem and sheath in main crop rice under N1 treatment increased by 50.57%compared with N4 treatment.The canopy light interception rate of N1 treatment increased by 5.07%compared with N4 treatment at the full heading stage of the ratoon crop.Therefore,the total actual yield was the highest in the main and its ratoon crops under N1 treatment,averaging 17351.23 kg ha;in two-year trials,which was 23.00%higher than that in the conventional fertilization treatment(N4).The results showed that appropriate nitrogen treatment was able to produce a good crop stand in the main crop,which was essential for producing a good ratoon crop population and high yield especially under mechanized cultivation with low stubble height of the main crop.The study suggested that shifting the proper nitrogen application amounts to the late growth stage of the main crop,such as N1 treatment,not only had a higher productive effect on ensuring the yield of the main crop,but also had a positive effect on the axillary bud sprouts from the stubbles for ratoon rice,resulting in an increased percentage of productive panicles and achieving the goal of one planting with two good harvests under the conditions of our study.展开更多
基金Supported by National Nonprofit Institute Research Grant of CAAS(IARRP-2015-7)Key Laboratory of Nonpoint Source Pollution Control,Ministry of Agriculture,P.R.China,Chinese Academy of Agricultural Sciences Science and Technology Innovation Project in 2017the Public Welfare Industry Science and Technology Projects for financing the research (no.200903011)
文摘With the improvement of agricultural mechanization equipment levels, the mechanized wheat harvesting level has been above 80% and the rate of wheat straw returned has increased significantly in the main wheat production of wheat of northern countryside in China. Chinese government popularized the beneficial agronomic measures in the process of wheat straw returned field by mechanization. The agronomic measure was reducing the wheat straw stubble height(WSSH) not more than 20 cm.However, local government didn't apply and disseminate the measure, because in practice the cost of fuel consumption was high, and the operation time of harvesting was longer than ever. The machinery operators and farmers needed to support extra fuel cost and time if they took government's advice. In fact, the objective subsidy policy of fuel cost on reducing WSSH was not been formulated by all levels of government. Therefore, the set of agronomic measure couldn't be popularized in main wheat production area of North China. Our research addressed to master the changing feature of fuel cost and mechanical efficiency,seeking suitable subsidy standard, providing some useful and constructive suggestions to improve subsidy policy of fuel consumption cost for national government department. The study carried out the tracking experiments of the operation efficiency and fuel costs of farm harvester in the situation of different WSSH in 2010 in Xushui District of Hebei Province. In conclusion, the operation time of harvesting decline and machinery fuel consumption cost increased along with the decreasing of WSSH. First for the older harvester, the operation efficiency would decline by 18.7% when the WSSH changed from 20 cm to 10 cm, the cost would increase 4.7%, exact cost was 152.2CNY per hectare. For the new harvester, the operation efficiency would decline by 39.9% when the WSSH changed from 20 cm to 15 cm, the cost would increase 4.6%, exact cost was 368.4CNY per hectare. We provided about 375 CNY per hectare to the mechanical operators and farmer who attended this project, and they were willing to accept the subsidies. We also put forwards some policy suggestions on promoting agronomic measures of reducing WSSH including strengthen the construction of agricultural machinery service system, practise a special fuel consumption subsidies of agricultural machinery and open up new paths for combine sales and circulation.
基金supported by the Key Research and Development Program of Heilongjiang,China(Grant No.2022ZX01A25)Cooperative Funding between Huazhong Agricultural University and Shenzhen Institute of Agricultural Genomics(Grant No.SZYJY2022014)+2 种基金Fundamental Research Funds for the Central Universities,Beijing,China(Grant Nos.2662022JC006 and 2662022ZHYJ002)National Natural Science Foundation of China(Grant No.32101819)Huazhong Agriculture University Research Startup Fund,China(Grant Nos.11041810340 and 11041810341).
文摘Pre-harvest yield prediction of ratoon rice is critical for guiding crop interventions in precision agriculture.However,the unique agronomic practice(i.e.,varied stubble height treatment)in rice ratooning could lead to inconsistent rice phenology,which had a significant impact on yield prediction of ratoon rice.Multi-temporal unmanned aerial vehicle(UAV)-based remote sensing can likely monitor ratoon rice productivity and reflect maximum yield potential across growing seasons for improving the yield prediction compared with previous methods.Thus,in this study,we explored the performance of combination of agronomic practice information(API)and single-phase,multi-spectral features[vegetation indices(VIs)and texture(Tex)features]in predicting ratoon rice yield,and developed a new UAV-based method to retrieve yield formation process by using multi-temporal features which were effective in improving yield forecasting accuracy of ratoon rice.The results showed that the integrated use of VIs,Tex and API(VIs&Tex+API)improved the accuracy of yield prediction than single-phase UAV imagery-based feature,with the panicle initiation stage being the best period for yield prediction(R^(2) as 0.732,RMSE as 0.406,RRMSE as 0.101).More importantly,compared with previous multi-temporal UAV-based methods,our proposed multi-temporal method(multi-temporal model VIs&Tex:R^(2) as 0.795,RMSE as 0.298,RRMSE as 0.072)can increase R^(2) by 0.020-0.111 and decrease RMSE by 0.020-0.080 in crop yield forecasting.This study provides an effective method for accurate pre-harvest yield prediction of ratoon rice in precision agriculture,which is of great significance to take timely means for ensuring ratoon rice production and food security.
基金funded by the National Key Research and Development Program of China(2016YFD0300508,2017YFD0301602 and 2018YFD0301105)the FujianTaiwan Joint Innovative Centre for Germplasm Resources and Cultivation of Crop,China(Fujian 2011 Program+1 种基金2015-75)the Science and Technology Development Fund of Fujian Agriculture and Forestry University,China(KF2015043)。
文摘This study attempted to clarify the carrying-over effect of different nitrogen treatments applied to the main crop on the crop population growth and yield formation of ratoon rice under mechanized cultivation in Southeast China.Based on the constant total nitrogen application amounts(225.00 kg ha;)in the main crop,an experiment with different ratios of basal and topdressing nitrogen fertilizer(the ratio of basal fertilizer:primary tillering fertilizer:secondary tillering fertilizer:booting fertilizer at 3:1:2:4(N1),3:2:1:4(N2),3:3:0:4(N3),and 4:3:0:3(N4),respectively,and a control without nitrogen treatment(N0))was set up across two consecutive years in field using hybrid rice variety Yongyou 1540 as the test materials.The results showed that the total tiller number and effective tillering percentage increased in the main crop under the N1 treatment,more nitrogen fertilizer applied in late growth stage of the main crop,and its effective tillering percentage of the main crop was the highest at up to 70.18%,which was 9.15%higher than that of conventional fertilization treatment(N4),more nitrogen fertilizer applied in early growth stage of the main crop.The same tendency was observed in leaf area index(LAI)value of the main crop and its subsequent ratoon rice,which were 16.52 and 29.87%higher,respectively,in the N1 treatment than that in the N4 treatment at the full heading stage.The same was true in the case of the transport rates of stem and sheath dry mater and the canopy light interception rates in both the main and its ratoon crops.The transport rate of stem and sheath in main crop rice under N1 treatment increased by 50.57%compared with N4 treatment.The canopy light interception rate of N1 treatment increased by 5.07%compared with N4 treatment at the full heading stage of the ratoon crop.Therefore,the total actual yield was the highest in the main and its ratoon crops under N1 treatment,averaging 17351.23 kg ha;in two-year trials,which was 23.00%higher than that in the conventional fertilization treatment(N4).The results showed that appropriate nitrogen treatment was able to produce a good crop stand in the main crop,which was essential for producing a good ratoon crop population and high yield especially under mechanized cultivation with low stubble height of the main crop.The study suggested that shifting the proper nitrogen application amounts to the late growth stage of the main crop,such as N1 treatment,not only had a higher productive effect on ensuring the yield of the main crop,but also had a positive effect on the axillary bud sprouts from the stubbles for ratoon rice,resulting in an increased percentage of productive panicles and achieving the goal of one planting with two good harvests under the conditions of our study.