ABSTRACT

Variable rate fertilization is one of the core technologies of precision agriculture, and it is particularly important to develop a representative field sampling scheme with less workload. A grid sampling of 1 m × 1 m was conducted on a pomegranate garden of 414 m² in Nanzhuang Town, Jianshui County, Honghe Hani and Yi Autonomous Prefecture, Yunnan Province, and set up 7 groups of sample point deletion schemes to study the reasonable sampling spacing of soil nutrients. Based on the grading standard of soil nutrients in plow layer, the distribution of soil nutrients was statistically analyzed by using classical statistical methods to reveal the spatial distribution variability of soil nutrients. We then utilized a geostatistical method to interpolate the soil nutrient to obtain the soil nutrient distribution map, and compared the soil nutrient distribution map of the deletion sampling scheme with the original sampling scheme A in shape and area. Results revealed that the deletion scheme E was the most consistent with the sampling results of the full coverage sampling scheme A, and the number of soil sampling could be reduced by half under the premise of meeting the requirements of precise fertilization. The field experiment showed that the variable rate fertilization could save 26%, 54% and 34% nitrogen, phosphorus and potassium fertilizer compared with the farmers’ conventional fertilization, the total yield of soft seed pomegranate increased by 41.52%, and the sugar content, sugar–acid ratio and vitamin C content of pomegranate grain increased by 11.79%, 51.26% and 31.59%. The results also provide support to determine sampling spacing, spatial variability of soil nutrients and variable rate fertilization in precision farming.

摘要

变率施肥是精准农业的核心技术之一，制定具有代表性、工作量较小的田间取样方案尤为重要。在 414 m ²的石榴园上进行了 1 m × 1 m 的网格采样在云南省红河哈尼族彝族自治州建水县南庄镇，设置7组样点删除方案，研究土壤养分的合理采样间距。根据耕层土壤养分分级标准，采用经典统计方法对土壤养分分布进行统计分析，揭示土壤养分空间分布变异性。然后我们利用地统计学方法对土壤养分进行插值得到土壤养分分布图，并在形状和面积上将删除抽样方案的土壤养分分布图与原始抽样方案A进行了比较。结果表明，删除方案E与全覆盖抽样方案A的抽样结果最一致，在满足精准施肥要求的前提下，可将土壤取样次数减少一半。田间试验表明，与农户常规施肥相比，变量施肥可节约氮、磷、钾肥26%、54%和34%，软籽石榴总产量提高41.52%，含糖量、石榴籽粒糖酸比和维生素C含量分别提高了11.79%、51.26%和31.59%。结果还为确定采样间隔、土壤养分的空间变异性和精准农业中的可变施肥提供了支持。54%和34%氮磷钾肥与农户常规施肥相比，软籽石榴总产量提高41.52%，石榴籽粒糖含量、糖酸比和维生素C含量提高11.79 %、51.26% 和 31.59%。结果还为确定采样间隔、土壤养分的空间变异性和精准农业中的可变施肥提供了支持。54%和34%氮磷钾肥与农户常规施肥相比，软籽石榴总产量提高41.52%，石榴籽粒糖含量、糖酸比和维生素C含量提高11.79 %、51.26% 和 31.59%。结果还为确定采样间隔、土壤养分的空间变异性和精准农业中的可变施肥提供了支持。