以环塔里木盆地阿克苏、喀什、和田及巴州4个地区红枣园为研究对象,测定0~20、20~40、40~60 cm 土壤有机碳(SOC)、全氮(TN)、全磷(TP)含量并分析其化学计量比.结果表明,果园土壤SOC、TN、TP含量及其化学计量比除TP含量和C:N外均低于中国土壤平均水平.0~60 cm 土壤SOC、TN含量及C∶P、N∶P均表现为阿克苏地区最高,和田地区最低;土壤TP含量表现为阿克苏地区最高,巴州地区最低;C∶N表现为巴州地区最高,喀什地区最低.随土层深度的增加,4个地区土壤SOC、TN、TP含量及C∶P、N∶P均降低;除和田地区外,其他地区土壤C:N均随土层深度的增加而升高.冗余分析结果表明,果园土壤SOC、TN、TP含量及其化学计量比受到纬度、经度和电导率等环境因子的影响.综上所述,环塔里木盆地红枣园土壤总体上表现出养分分配不均的现象,建议在施肥过程中适当增加氮肥的施用和有机肥的配施.
C,N and P stoichiometric characteristics of jujube orchard soils in the ring tarim basin
The organic carbon(SOC),total nitrogen(TN)and total phosphorus(TP)contents of 0~20 cm,20~40 cm and 40~60 cm soils were determined and analysed for their stoichiometric ratios in the jujube orchards in Aksu,Kashgar,Hetian and Bazhou in the vicinity of the tarim basin in Xinjiang.The results showed that the SOC,TN and TP contents and their stoichiometric ratios of 0~60 cm soils were lower than the average level of Chinese soils,except for TP and C∶N.The SOC,TN contents and C∶P and N∶P of 0~60 cm soils were the highest in Aksu and the lowest in Hetian;the TP contents were the highest in Aksu and the lowest in Bazhou;and the C∶N was the highest in Bazhou and the lowest in Kashgar.With the increase of soil depth,soil SOC,TN,TP contents and C∶P and N∶P decreased in the four regions;except for Hetian region,soil C∶N increased with the increase of soil depth in all regions.The results of redundancy analyses showed that the important influencing factors of orchard soil SOC,TN and TP contents and their stoichiometric ratios were latitude,longitude and electric conductivity.In conclusion,the soil of the jujube orchards in the ring tarim basin generally showed uneven nutrient distribution,and it is recommended to appropriately increase the application of nitrogen fertiliser and the dosing of organic fertiliser in the fertilisation process.