A field trial was carried out to study the nitrogen fertilizer recovery by four crops in succession in manurial loess soil in Yangling. The results showed that the nitrogen fertilizer not only had the significant effe...A field trial was carried out to study the nitrogen fertilizer recovery by four crops in succession in manurial loess soil in Yangling. The results showed that the nitrogen fertilizer not only had the significant effects on the first crop , but also had longer residual effects, even on the fourth crop. The average apparent nitrogen fertilizer recovery by the first crop was 31.7%, and the accumulative nitrogen recovery by the 4 crops was high as 62.3%, and the latter was double as the former. It is quite clear that the nitrogen fertilizer recovery by the first crop was not reliable for estimating the nitrogen fertilizer unless the residual effect of nitrogen fertilizer was included.展开更多
The external costs and the optimum use of nitrogen fertilizer based on the balance of economic and ecological benefits was studied with the paddy field system of Dongting Lake area, one of the main food production reg...The external costs and the optimum use of nitrogen fertilizer based on the balance of economic and ecological benefits was studied with the paddy field system of Dongting Lake area, one of the main food production regions in China. The environmental impact was economically evaluated using methods of the environmental impact economical evaluation. The optimum use of nitrogen fertilizer was calculated based on the exterior diseconomy theory and by using the production function model. Both ecological benefits and farmers＇ economic benefits were considered. It was calculated on the data from 2002 that the losses caused by inappropriate utilization of nitrogen fertilizer in the process of food production were fishery, 0.1 × 10^7 RMB yuan; water treatment, 1.02 × 10^8 RMB yuan; tour business, 0.11 ×10^8 RMB yuan, and habitation environment, 0.3 × 10^7 RMB yuan, totally equivalent to 0.41 RMB yuan kg^-1 N. The economically satisfactory and the ecological agronomic nitrogen fertilizer dose for current production was 138 and 137 kg ha^-1, respectively. The research showed that the actual nitrogen fertilizer application amount in the paddy field system of the Dongting Lake area already reached or exceeded the farmers＇ economic satisfaction and the ecological agronomic nitrogen fertilizer dose for current production. An environmental tax is suggested to impose on over-use of nitrogen fertilizer.展开更多
Rice yields and nitrogen use efficiencies were studied at five sites in southwest China using two nitrogen fertilization rates and five controlled-release urea（ CRU） to ordinary urea（ U） ratios. The fertilizer tre...Rice yields and nitrogen use efficiencies were studied at five sites in southwest China using two nitrogen fertilization rates and five controlled-release urea（ CRU） to ordinary urea（ U） ratios. The fertilizer treatments significantly increased rice yields compared with the control（ no nitrogen added） yields to different degrees at different sites. Applying CRU and U increased the rice yield more than adding the same amount of nitrogen as U only. Higher increasing production rate were found using a nitrogen application rate of 105 kg/hm2 than 150 kg/hm2. A 70∶ 30 CRU∶ U ratio increased the yield more than other four ratios. Nitrogen use efficiency was 21. 9% higher using a nitrogen application rate of 105 kg/hm^2 than 150 kg/hm^2,and 46. 6%,38. 1%,34. 7%,and 22. 2% higher than when only U was applied when CRU∶ U ratios of 70 ∶ 30,50 ∶ 50,100 ∶ 0,and 30 ∶ 70,respectively,were used. A 70 ∶ 30 CRU ∶ U ratio gave the highest economic output（ yuan/hm^2）. Applying both CRU and U gave an output 3 078. 87 yuan/hm^2 higher at a nitrogen application rate of 150 kg/hm^2 than at a nitrogen application rate of 105 kg/hm^2. Economic output was always higher using both CRU and U than using U only. The highest economic output was given using a 70∶ 30 CRU∶ U ratio.Increasing the amount of nitrogen added decreased the output efficiency（ per hm2） because CRU is expensive. Significant relationships were found between the yield increase rate and the proportion of CRU added（ regression equation y = 7. 429 x-185. 7,R^2= 0. 663） and between the total rainfall over the whole growth period and the proportion of CRU added（ y =-0. 087 1 x ＋ 112. 29,R^2= 0. 687 9）. These regression equations can be used to determine the appropriate proportion of CRU that should be added at a site,depending on the rainfall and target rice yield.展开更多
探究施氮量和播种量互作对冬小麦产量、生长发育和生态场特性的影响,利用生态场理论揭示不同小麦群体竞争力差异及其与产量的关系,明确冬小麦适宜的氮肥用量和播种量,为冬小麦高产高效生产提供依据。2020年10月至2022年6月于河南省温县...探究施氮量和播种量互作对冬小麦产量、生长发育和生态场特性的影响,利用生态场理论揭示不同小麦群体竞争力差异及其与产量的关系,明确冬小麦适宜的氮肥用量和播种量,为冬小麦高产高效生产提供依据。2020年10月至2022年6月于河南省温县设置冬小麦氮肥用量和播种量双因素交互田间试验,研究了施氮量(0、90、180、270、360 kg N hm^(–2))和播种量(135、180、225、270 kg hm^(–2))对冬小麦籽粒产量、氮积累量等的影响,测定小麦株高、冠幅和单株分蘖等生长发育指标,计算个体生态势和群体生态场并分析其与产量间关系。结果表明,两年取得最高产量的播种量均为225 kg hm^(–2),施氮量分别为270 kg hm^(–2)和180 kg hm^(–2),较其他处理平均增产7.5%和18.1%;施氮后小麦氮积累量提高57.3%,生态势提高72.7%;提高播种量后群体茎蘖数提高34.7%,单株小麦发育水平下降,生态势下降11.4%。施氮量和播种量通过共同影响株高和冠幅影响生态势影响距离,其他处理较135 kg hm^(–2)播种量不施氮处理影响距离提高23.0%。冬小麦群体生态场面积与产量呈一元二次函数关系,施氮和提高播种量,冬小麦群体生态场面积分别提高116.7%和52.5%。本试验条件下,通过氮肥用量和播种量调控冬小麦群体发育质量,控制群体竞争力,构建了理想群体,实现了冬小麦高产与高效生产;冬小麦氮密优化组合施氮量239.8 kg hm^(–2)、播种量228.7 kg hm^(–2),具有适宜的生态场和理想群体,产量较高,可在豫北地区推广应用。展开更多
文摘A field trial was carried out to study the nitrogen fertilizer recovery by four crops in succession in manurial loess soil in Yangling. The results showed that the nitrogen fertilizer not only had the significant effects on the first crop , but also had longer residual effects, even on the fourth crop. The average apparent nitrogen fertilizer recovery by the first crop was 31.7%, and the accumulative nitrogen recovery by the 4 crops was high as 62.3%, and the latter was double as the former. It is quite clear that the nitrogen fertilizer recovery by the first crop was not reliable for estimating the nitrogen fertilizer unless the residual effect of nitrogen fertilizer was included.
文摘The external costs and the optimum use of nitrogen fertilizer based on the balance of economic and ecological benefits was studied with the paddy field system of Dongting Lake area, one of the main food production regions in China. The environmental impact was economically evaluated using methods of the environmental impact economical evaluation. The optimum use of nitrogen fertilizer was calculated based on the exterior diseconomy theory and by using the production function model. Both ecological benefits and farmers＇ economic benefits were considered. It was calculated on the data from 2002 that the losses caused by inappropriate utilization of nitrogen fertilizer in the process of food production were fishery, 0.1 × 10^7 RMB yuan; water treatment, 1.02 × 10^8 RMB yuan; tour business, 0.11 ×10^8 RMB yuan, and habitation environment, 0.3 × 10^7 RMB yuan, totally equivalent to 0.41 RMB yuan kg^-1 N. The economically satisfactory and the ecological agronomic nitrogen fertilizer dose for current production was 138 and 137 kg ha^-1, respectively. The research showed that the actual nitrogen fertilizer application amount in the paddy field system of the Dongting Lake area already reached or exceeded the farmers＇ economic satisfaction and the ecological agronomic nitrogen fertilizer dose for current production. An environmental tax is suggested to impose on over-use of nitrogen fertilizer.
基金Supported by Study and Mode Construction of Water and Fertilizer Coupling and Accurate Fertilizer and Drug Reduction High-yielding Synergistic Technology during Diversified Rice Planting in the West Part of the Middle and Lower Reaches of the Yangtze River(2017YFD0301700)National System of Rice Industrial Technology(CARS-01-25)
文摘Rice yields and nitrogen use efficiencies were studied at five sites in southwest China using two nitrogen fertilization rates and five controlled-release urea（ CRU） to ordinary urea（ U） ratios. The fertilizer treatments significantly increased rice yields compared with the control（ no nitrogen added） yields to different degrees at different sites. Applying CRU and U increased the rice yield more than adding the same amount of nitrogen as U only. Higher increasing production rate were found using a nitrogen application rate of 105 kg/hm2 than 150 kg/hm2. A 70∶ 30 CRU∶ U ratio increased the yield more than other four ratios. Nitrogen use efficiency was 21. 9% higher using a nitrogen application rate of 105 kg/hm^2 than 150 kg/hm^2,and 46. 6%,38. 1%,34. 7%,and 22. 2% higher than when only U was applied when CRU∶ U ratios of 70 ∶ 30,50 ∶ 50,100 ∶ 0,and 30 ∶ 70,respectively,were used. A 70 ∶ 30 CRU ∶ U ratio gave the highest economic output（ yuan/hm^2）. Applying both CRU and U gave an output 3 078. 87 yuan/hm^2 higher at a nitrogen application rate of 150 kg/hm^2 than at a nitrogen application rate of 105 kg/hm^2. Economic output was always higher using both CRU and U than using U only. The highest economic output was given using a 70∶ 30 CRU∶ U ratio.Increasing the amount of nitrogen added decreased the output efficiency（ per hm2） because CRU is expensive. Significant relationships were found between the yield increase rate and the proportion of CRU added（ regression equation y = 7. 429 x-185. 7,R^2= 0. 663） and between the total rainfall over the whole growth period and the proportion of CRU added（ y =-0. 087 1 x ＋ 112. 29,R^2= 0. 687 9）. These regression equations can be used to determine the appropriate proportion of CRU that should be added at a site,depending on the rainfall and target rice yield.
文摘探究施氮量和播种量互作对冬小麦产量、生长发育和生态场特性的影响,利用生态场理论揭示不同小麦群体竞争力差异及其与产量的关系,明确冬小麦适宜的氮肥用量和播种量,为冬小麦高产高效生产提供依据。2020年10月至2022年6月于河南省温县设置冬小麦氮肥用量和播种量双因素交互田间试验,研究了施氮量(0、90、180、270、360 kg N hm^(–2))和播种量(135、180、225、270 kg hm^(–2))对冬小麦籽粒产量、氮积累量等的影响,测定小麦株高、冠幅和单株分蘖等生长发育指标,计算个体生态势和群体生态场并分析其与产量间关系。结果表明,两年取得最高产量的播种量均为225 kg hm^(–2),施氮量分别为270 kg hm^(–2)和180 kg hm^(–2),较其他处理平均增产7.5%和18.1%;施氮后小麦氮积累量提高57.3%,生态势提高72.7%;提高播种量后群体茎蘖数提高34.7%,单株小麦发育水平下降,生态势下降11.4%。施氮量和播种量通过共同影响株高和冠幅影响生态势影响距离,其他处理较135 kg hm^(–2)播种量不施氮处理影响距离提高23.0%。冬小麦群体生态场面积与产量呈一元二次函数关系,施氮和提高播种量,冬小麦群体生态场面积分别提高116.7%和52.5%。本试验条件下,通过氮肥用量和播种量调控冬小麦群体发育质量,控制群体竞争力,构建了理想群体,实现了冬小麦高产与高效生产;冬小麦氮密优化组合施氮量239.8 kg hm^(–2)、播种量228.7 kg hm^(–2),具有适宜的生态场和理想群体,产量较高,可在豫北地区推广应用。
