基于光谱参数估算滴灌小麦干物质氮肥偏生产力和农学效率

为了解应用遥感技术估测滴灌小麦氮肥利用效率的可行性,以新春17号、新春6号和新春22号为材料,通过大田试验,分析了不同施氮处理下小麦干物质氮肥偏生产力(RDN)和干物质氮肥农学效率(DMA En)与光谱参数的相关关系,并建立小麦RDN和DMAEn的光谱参数估算模型.结果表明,在分蘖、抽穗和开花期RDN与绿度植被指数和比值植被指数呈极显著正相关,在拔节和抽穗期DMAEn与土壤调整比值植被指数和归一化差值植被指数呈显著正相关.光谱参数估算模型的均方根误差为7.64～33.31,说明利用光谱参数可以有效地估算小麦氮肥利用效率.

Estimation of the Partial Productivity and Agronomic Efficiency of N Application on Dry Matter of Wheat under Drip Irrigation by Spectral Parameters

The aim of this study is to understand the feasibility of applying remote sensing to estimate nitrogen nutrition in wheat under drip irrigation. Field experiments were conducted with different wheat cultivars of Xinchun 17, Xinchun 6 and Xinchun 22, the relationship was analyzed between spectral parameters and the ratio of dry matter to amount of nitrogen (RDN) and dry matter agronomic efficiency of applied N (DMAEn), and the estimating models were established for RDN and DMAEn at the growth stages of wheat. The results indicated that there were highly significant correlations between the RDN with GreenNDVI and RVI at jointing, heading and anthesis stages, and there were significant correlations between the DMAEn with SARVI and NDVI at jointing and anthesis stages, the estimated models of RDN and DMAEn were established, and the root mean square errors (RMSE ) ranged from 7.64 to 33.31. The results indicated that the RDN and DMAEn can be effectively estimated by spectral parameters during growth stages of wheat.