To provide a scientific basis for sustainable land management, a 20-year fertility experiment was conducted in Changwu County, Shaanxi Province, China to investigate the effects of long-term application of chemical fe...To provide a scientific basis for sustainable land management, a 20-year fertility experiment was conducted in Changwu County, Shaanxi Province, China to investigate the effects of long-term application of chemical fertilizers on wheat grain yield and yield stability on the Loess Plateau using regression and stability analysis. The experiment consisted of 17 fertilizer treatments, containing the combinations of different N and P levels, with three replications arranged in a randomized complete block design. Nitrogen fertilizer was applied as urea, and P was applied as calcium superphosphate. Fertilizer rates had a large effect on the response of wheat yield to fertilization. Phosphorus, combined with N, increased yield significantly （P 〈 0.01）. In the unfertilized control and the N or P sole application treatments, wheat yield had a declining trend although it was not statistically significant. Stability analysis combined with the trend analysis indicated that integrated use of fertilizer N and P was better than their sole application in increasing and sustaining the productivity of rainfed winter wheat.展开更多
The primary objective to these study was to test NPKCaMg-fertilization induced ＂Zn（2＋）＂ bioavailability in triticale rhizosphere soils. Soil and plant samples were taken from experimental sites randomly, and were...The primary objective to these study was to test NPKCaMg-fertilization induced ＂Zn（2＋）＂ bioavailability in triticale rhizosphere soils. Soil and plant samples were taken from experimental sites randomly, and were analysed in laboratory to plant available Zn^2＋） content. Zinc ＂Zn（2＋）＂ concentrations showed a large variability to interactions with soil＇s pH values. It ranged from 0.4 and 1.36 mg kg1. Soil＇s ＂Zn（2＋）＂ contents had been significantly lower than International Soil Limit （ISL） value （70 mg kgl）, consequently. Plant available ＂Zn（2＋）＂ contents from triticale rhizosphere soils in Leaf＋Straw ranged from 10.1 to 38.4 mg kgl, and in Seed from 26.9 to 52.0 mg kg1. ＂Zn（2＋）＂s Actual Translocation Index （ATI） from rhizosphere soils to Leaf＋Straw had as average 23.6, and to grain 43. 1. ＂Zn（2＋）＂ Leaf＋Straw bioacummulation （g hal） had as average 13.4, Grain 23.2, and total （Leaf＋Straw＋Grain） 36.6. ＂Zn（2＋）＂translocation from soils to Leaf＋Straw was 37% lower than to Grain. Ultimately, within the range of experimental conditions tested these results are present that ＂Zn（2＋）＂ tends to accumulate to triticale organs to create the conditions for toxicity effects in Food Chane.展开更多
Soil productivity is the ability of a soil, in its normal environment, to support plant growth and can be evaluated with respect to crop production in unfertilized soil within the agricultural ecosystem. Both soil pro...Soil productivity is the ability of a soil, in its normal environment, to support plant growth and can be evaluated with respect to crop production in unfertilized soil within the agricultural ecosystem. Both soil productivity and fertilizer applications affect crop yields. A long-term experiment with a winter wheat-summer maize rotation was established in 1989 in a field of the Fengqiu State Key Agro-Ecological Experimental Station, a region typical of the North China Plain, including seven treatments： 1） a balanced application of NPK chemical fertilizers （NPK）; 2） application of organic fertilizer （OM）; 3） application of 50% organic fertilizer and 50% NPK chemical fertilizers （1/2OMN）; 4） application of NP chemical fertilizers （NP）; 5） application of PK chemical fertilizer （PK）; 6） application of NK chemical fertilizers （NK）; and 7） unfertilized control （CK）. To investigate the effects of fertilization practices on soil productivity, further pot tests were conducted in 2007-2008 using soil samples from the different fertilization treatments of the long-term field experiment. The soil sample of each treatment of the long-term experiment was divided into three pots to grow wheat： with no fertilization （Potunf）, with balanced NPK fertilization （POtNPK）, and with the same fertilizer（s） of the long-term field experiment （Potori）. The fertilized soils of the field experiment used in all the pot tests showed a higher wheat grain yield and higher nutrient uptake levels than the unfertilized soil. Soil productivity of the treatments of the field experiment after 18 years of continuous fertilizer applications were ranked in the order of OM 〉 1/2OMN 〉 NPK 〉 NP 〉 PK 〉 NK 〉 CK. The contribution of soil productivity of the different treatments of the field experiment to the wheat grain yield of Potori was 36.0%-76.7%, with the PK and NK treatments being higher than the OM, 1/2OMN, NPK, and NP treatments since the soil in this area was deficient in N and P and rich in K. Wheat grain yields of PotNPK were higher than those of Potori and Potunf. The N, P, and K use efficiencies were higher in POtNPK than Potori and significantly positively correlated with wheat grain yield. Soil organic matter could be a better predictor of soil productivity because it correlated more strongly than other nutrients with the wheat grain yield of Potuf. Wheat yields of POtNPK showed a similar trend to those of Potunf, indicating that soil productivity improvement was essential for a further increase in crop yield. The long-term applications of both organic and chemical fertilizers were capable of increasing soil productivity on the North China Plain, but the former was more effective than the latter. The balanced application of NPK chemical fertilizers not only increased soil productivity, but also largely increased crop yields, especially in soils with lower productivity. Thus, such an approach should be a feasible practice for the sustainable use of agricultural soils on the North China Plain, particularly when taking into account crop yields, labor costs, and the limited availability of organic fertilizers.展开更多
基金Project supported by the Agricultural Development Program of the Chinese Academy of Sciences (No. KSCX1-YWN1504)the West Light Foundation of the Chinese Academy of Sciences (No. 2005404)the National Natural Science Foundation of China (Nos. 50479065 and 40601041).
文摘To provide a scientific basis for sustainable land management, a 20-year fertility experiment was conducted in Changwu County, Shaanxi Province, China to investigate the effects of long-term application of chemical fertilizers on wheat grain yield and yield stability on the Loess Plateau using regression and stability analysis. The experiment consisted of 17 fertilizer treatments, containing the combinations of different N and P levels, with three replications arranged in a randomized complete block design. Nitrogen fertilizer was applied as urea, and P was applied as calcium superphosphate. Fertilizer rates had a large effect on the response of wheat yield to fertilization. Phosphorus, combined with N, increased yield significantly （P 〈 0.01）. In the unfertilized control and the N or P sole application treatments, wheat yield had a declining trend although it was not statistically significant. Stability analysis combined with the trend analysis indicated that integrated use of fertilizer N and P was better than their sole application in increasing and sustaining the productivity of rainfed winter wheat.
文摘The primary objective to these study was to test NPKCaMg-fertilization induced ＂Zn（2＋）＂ bioavailability in triticale rhizosphere soils. Soil and plant samples were taken from experimental sites randomly, and were analysed in laboratory to plant available Zn^2＋） content. Zinc ＂Zn（2＋）＂ concentrations showed a large variability to interactions with soil＇s pH values. It ranged from 0.4 and 1.36 mg kg1. Soil＇s ＂Zn（2＋）＂ contents had been significantly lower than International Soil Limit （ISL） value （70 mg kgl）, consequently. Plant available ＂Zn（2＋）＂ contents from triticale rhizosphere soils in Leaf＋Straw ranged from 10.1 to 38.4 mg kgl, and in Seed from 26.9 to 52.0 mg kg1. ＂Zn（2＋）＂s Actual Translocation Index （ATI） from rhizosphere soils to Leaf＋Straw had as average 23.6, and to grain 43. 1. ＂Zn（2＋）＂ Leaf＋Straw bioacummulation （g hal） had as average 13.4, Grain 23.2, and total （Leaf＋Straw＋Grain） 36.6. ＂Zn（2＋）＂translocation from soils to Leaf＋Straw was 37% lower than to Grain. Ultimately, within the range of experimental conditions tested these results are present that ＂Zn（2＋）＂ tends to accumulate to triticale organs to create the conditions for toxicity effects in Food Chane.
基金supported by the Knowledge Innovation Program of Chinese Academy of Sciences (Nos. KZCX2-YW-312 and KZCX2-YW-406-2)the National Natural Science Foundation of China (No. 40621001)
文摘Soil productivity is the ability of a soil, in its normal environment, to support plant growth and can be evaluated with respect to crop production in unfertilized soil within the agricultural ecosystem. Both soil productivity and fertilizer applications affect crop yields. A long-term experiment with a winter wheat-summer maize rotation was established in 1989 in a field of the Fengqiu State Key Agro-Ecological Experimental Station, a region typical of the North China Plain, including seven treatments： 1） a balanced application of NPK chemical fertilizers （NPK）; 2） application of organic fertilizer （OM）; 3） application of 50% organic fertilizer and 50% NPK chemical fertilizers （1/2OMN）; 4） application of NP chemical fertilizers （NP）; 5） application of PK chemical fertilizer （PK）; 6） application of NK chemical fertilizers （NK）; and 7） unfertilized control （CK）. To investigate the effects of fertilization practices on soil productivity, further pot tests were conducted in 2007-2008 using soil samples from the different fertilization treatments of the long-term field experiment. The soil sample of each treatment of the long-term experiment was divided into three pots to grow wheat： with no fertilization （Potunf）, with balanced NPK fertilization （POtNPK）, and with the same fertilizer（s） of the long-term field experiment （Potori）. The fertilized soils of the field experiment used in all the pot tests showed a higher wheat grain yield and higher nutrient uptake levels than the unfertilized soil. Soil productivity of the treatments of the field experiment after 18 years of continuous fertilizer applications were ranked in the order of OM 〉 1/2OMN 〉 NPK 〉 NP 〉 PK 〉 NK 〉 CK. The contribution of soil productivity of the different treatments of the field experiment to the wheat grain yield of Potori was 36.0%-76.7%, with the PK and NK treatments being higher than the OM, 1/2OMN, NPK, and NP treatments since the soil in this area was deficient in N and P and rich in K. Wheat grain yields of PotNPK were higher than those of Potori and Potunf. The N, P, and K use efficiencies were higher in POtNPK than Potori and significantly positively correlated with wheat grain yield. Soil organic matter could be a better predictor of soil productivity because it correlated more strongly than other nutrients with the wheat grain yield of Potuf. Wheat yields of POtNPK showed a similar trend to those of Potunf, indicating that soil productivity improvement was essential for a further increase in crop yield. The long-term applications of both organic and chemical fertilizers were capable of increasing soil productivity on the North China Plain, but the former was more effective than the latter. The balanced application of NPK chemical fertilizers not only increased soil productivity, but also largely increased crop yields, especially in soils with lower productivity. Thus, such an approach should be a feasible practice for the sustainable use of agricultural soils on the North China Plain, particularly when taking into account crop yields, labor costs, and the limited availability of organic fertilizers.
