不同施肥处理对西藏青稞产量和土壤结构的影响

Effects of Different Fertilization Treatments on Yield of Tibetan Highland Barley and Soil Structure

【目的】为探求提高青稞产量并有效改良土壤结构的施肥措施,研究了西藏自治区拉萨市不同施肥处理对青稞产量与土壤结构的影响。【方法】试验设置5个处理:不施肥(Control)、单施羊粪(M)、羊粪和氮磷肥配合施用(M+NP)、单施氮肥(N)、氮肥和磷肥配合施用(NP),采用田间试验和室内分析方法测定青稞产量和影响土壤结构的因素。【结果】与不施肥对照相比,氮肥、磷肥配施(NP)与施用有机肥(M和M+NP)均能显著提高青稞产量;化肥与有机肥配施能够改善土壤容重、紧实度和土壤结构,化肥与有机肥配施土壤容重下降幅度最大为12.13%;土壤紧实度随青稞生育期的推进呈下降趋势,收获前后羊粪+氮肥+磷肥(M+NP)配施土壤紧实度下降幅度最大为31.26%;化肥与有机肥配施提高了土壤有机质的含量,促进了土壤大团聚体(>2 mm)的形成,降低了土壤微团聚体(<0.25 mm)在土壤中的比重,但施用化肥没有显著影响;施用有机肥能显著提高土壤团聚体的平均重量直径和几何平均直径,而仅施化肥无显著影响。【结论】施用有机肥可以提高西藏青稞产量和土壤有机质含量,改善土壤容重、紧实度和土壤结构,从而增强西藏自治区粮食生产的稳定性和可持续性。

[ Objective] In order to seek the appropriate fertilization techniques,which could increase the yield of Tibetan barley highland bar- ley and effectively improve soil structure ,field experiment and experimental analysis were carried out to study the effects of the different ferti- lization treatments on yield of highland barley and soil structure in Lhasa city, the Tibet autonomous region, China. [ Method ] The experiment included five treatments with three replicates： sheep manure treatment （M）, sheep manure and nitrogen, phosphate fertilizer treatment （M ＋ NP）, the single N fertilization treatment （ N）, Combined application of nitrogen and phosphorus fertilizer treatment （ NP）, and no input of fer- tilizers as control treatment（Control）. The yield of highland barley and the factors affecting soil structure were analyzed using field experiment and experimental analysis methods. [ Result] Compared with the unfertilized control, inorganic NP fertilization and manure amendment （M and M ＋ NPK） significantly increased the yield of highland barley. The application of fertilizer and manure could improve soil bulk density, soil compaction and soil structure. Soil bulk density of the application of fertilizer and manure was the biggest drop of 12.13 %. Soil compac- tion was downward trend with growth period of crops, soil compaction was the biggest drop of 31.26 % under the organic manure ＋ nitrogen ＋ phosphorus fertilizer treatments. The application of fertilizer and manure increased the content of soil organic matter and promoted the for- mation of soil macro aggregates （ 〉 2 mm） with a corresponding decline in the proportion of micro aggregates （ 〈 0.25 mm） ,while no signifi- cant effects were found in the inorganic fertilization treatments. The values of mean weight diameter and geometric mean dimneter were signifi- candy higher in the manure-applied treatments compared with the control, but not in the inorganic fertilization treatments. [ Conclusion ] The application of manure can increase the yield of highland barley and improve the content of soil organic matter, soil bulk density, soil compac- tion and soil structure, thereby enhancing the stability and sustainability of crop production in the Tibet autonomous region.