A long-term fertilization experiment was set up in northern Xinjiang, China to evaluate the dynamics of crop production and soil organic carbon （SOC） from 1990 to 2012 with seven fertilization treatments. The seven ...A long-term fertilization experiment was set up in northern Xinjiang, China to evaluate the dynamics of crop production and soil organic carbon （SOC） from 1990 to 2012 with seven fertilization treatments. The seven treatments included an unfertilized control （CK） and six different combinations of phosphorus （P）, potassium （K）, nitrogen （N）, straw （S） and animal manure （M）. The balanced fertilization treatments had significantly （P〈0.05） higher average yields than the unbalanced ones. The treatment with 2/3 N from potassium sulfate （NPK） and 1/3 N from farmyard manure （NPKM） had a higher average yield than the other treatments. The average yields （over the 23 years） in the treatments of NPK, and urea, calcium superphosphate （NP） did not differ significantly （P〉0.05） but were higher than that in the treatment with urea and potassium sulfate （NK; P〈0.05）. The results also show that the highest increases in SOC （P〈0.05） occurred in NPKM with a potential increase of 1.2 t C/（hm2.a）. The increase in SOC was only 0.31, 0.30 and 0.12 t C/（hm2.a） for NPKS （9/10 N from NPK and 1/10 N from straw）, NPK and NP, respectively; and the SOC in the NP, NK and CK treatments were approaching equilibrium and so did not rise or fall significantly over the 23-year experiment. A complete NPK plus manure fertilization program is recommended for this extremely arid region to maximize both yields and carbon sequestration.展开更多
采用密闭通气法研究了紫花苜蓿草地原位氨挥发损失。结果表明,紫花苜蓿(M ed icag o sa tiva L)草地分枝期、现蕾期和开花期昼夜都有氨挥发损失;连作苜蓿草地分枝期、现蕾期和开花期的昼夜平均氨挥发速率分别为54.3、111.6和181.9μg/(m...采用密闭通气法研究了紫花苜蓿草地原位氨挥发损失。结果表明,紫花苜蓿(M ed icag o sa tiva L)草地分枝期、现蕾期和开花期昼夜都有氨挥发损失;连作苜蓿草地分枝期、现蕾期和开花期的昼夜平均氨挥发速率分别为54.3、111.6和181.9μg/(m2.h);连作苜蓿草地的昼夜氨挥发速率随着生育期的推移迅速增加;施P 26.2 kg/hm2可以降低连作苜蓿草地的氨挥发损失;轮作苜蓿草地分枝期、现蕾期和开花期的昼夜平均氨挥发速率分别为49.2、346.5和149.1μg/(m2.h);轮作改变了氨挥发速率的变化规律,现蕾期比连作高2.1倍,开花期比连作低18.0%。展开更多
基金funded by the National Basic Research Program of China(2014CB954200)the National Natural Science Foundation of China(41425007,41005001)the National Gray Desert Soil Fertility and Fertilizer Efficiency Monitoring Station of China
文摘A long-term fertilization experiment was set up in northern Xinjiang, China to evaluate the dynamics of crop production and soil organic carbon （SOC） from 1990 to 2012 with seven fertilization treatments. The seven treatments included an unfertilized control （CK） and six different combinations of phosphorus （P）, potassium （K）, nitrogen （N）, straw （S） and animal manure （M）. The balanced fertilization treatments had significantly （P〈0.05） higher average yields than the unbalanced ones. The treatment with 2/3 N from potassium sulfate （NPK） and 1/3 N from farmyard manure （NPKM） had a higher average yield than the other treatments. The average yields （over the 23 years） in the treatments of NPK, and urea, calcium superphosphate （NP） did not differ significantly （P〉0.05） but were higher than that in the treatment with urea and potassium sulfate （NK; P〈0.05）. The results also show that the highest increases in SOC （P〈0.05） occurred in NPKM with a potential increase of 1.2 t C/（hm2.a）. The increase in SOC was only 0.31, 0.30 and 0.12 t C/（hm2.a） for NPKS （9/10 N from NPK and 1/10 N from straw）, NPK and NP, respectively; and the SOC in the NP, NK and CK treatments were approaching equilibrium and so did not rise or fall significantly over the 23-year experiment. A complete NPK plus manure fertilization program is recommended for this extremely arid region to maximize both yields and carbon sequestration.
文摘采用密闭通气法研究了紫花苜蓿草地原位氨挥发损失。结果表明,紫花苜蓿(M ed icag o sa tiva L)草地分枝期、现蕾期和开花期昼夜都有氨挥发损失;连作苜蓿草地分枝期、现蕾期和开花期的昼夜平均氨挥发速率分别为54.3、111.6和181.9μg/(m2.h);连作苜蓿草地的昼夜氨挥发速率随着生育期的推移迅速增加;施P 26.2 kg/hm2可以降低连作苜蓿草地的氨挥发损失;轮作苜蓿草地分枝期、现蕾期和开花期的昼夜平均氨挥发速率分别为49.2、346.5和149.1μg/(m2.h);轮作改变了氨挥发速率的变化规律,现蕾期比连作高2.1倍,开花期比连作低18.0%。
