Climate Change Data Portal
| DOI | 10.1016/j.agwat.2017.06.019 |
| Comparison of hourly and daily Penman-Monteith grass- and alfalfa-reference evapotranspiration equations and crop coefficients for maize under arid climatic conditions | |
| Ji X.B.; Chen J.M.; Zhao W.Z.; Kang E.S.; Jin B.W.; Xu S.Q. | |
| 发表日期 | 2017 |
| ISSN | 03783774 |
| 卷号 | 192 |
| 英文摘要 | The practical estimation of actual crop evapotranspiration (ETa) frequently involves calculating a reference crop evapotranspiration (ETref), and then applying suitable crop coefficients (Kc). Two standardized calculation procedures based on the Penman-Monteith equation are commonly used as ETref estimations (ETo for grass and ETr for alfalfa) across diverse environments. However, not much is known about the difference between ETo and ETr and their corresponding Kc values for maize in the arid environment of Northwest China with maize being the dominant crop. Estimates from the two procedures were comprehensively compared at both hourly and daily time steps for 2013 and 2014 growing seasons. The sum-of-hourly ETr and ETo (summed from hourly values over 24 h periods) values were averagely lower than their corresponding daily ETr and ETo values (calculated from daily average meteorological data) by about 1% and 5% in 2013, and 2% and 7% in 2014, respectively. The ratios of ETr to ETo varied seasonally with a mean value slightly lower than the generalized value (1.35) for arid conditions, due primarily to the differences in responsiveness of both standardized PM equations to the trends and interations among input parameters. The Kc curves of maize based on grass-reference (Kco) and alfalfa-reference (Kcr) were experimentally derived using daily ETo and ETr combined with ETa measured by eddy covariance method. Results suggest the benefit and potentially improved accuracy for ETa estimation when applying alfalfa reference equation combined with the timestep-specific Kc curves under the arid conditions. These results provide an acceptable accuracy and precision for estimation of ETa of maize field use using the standardized Penman-Monteith equations, and offer the possibility of extrapolating new sets of Kco and Kcr to this region or other areas with similar climatic and crop management conditions. © 2017 Elsevier B.V. |
| 英文关键词 | Eddy covariance; Evapotranspiration; Northwestern China; Penman-Monteith equation; Sum-of-hourly; Well-watered conditions |
| URL | https://www2.scopus.com/inward/record.uri?eid=2-s2.0-85021767654&doi=10.1016%2fj.agwat.2017.06.019&partnerID=40&md5=8ce957db588788457cddcc97b1160737 |
| 语种 | 英语 |
| scopus关键词 | Evapotranspiration; Meteorology; Accuracy and precision; Crop evapotranspiration; Eddy covariance; Northwestern China; Penman-Monteith equations; Reference crop evapotranspirations; Reference evapotranspiration; Sum-of-hourly; Crops; agricultural management; alfalfa; arid environment; climate conditions; comparative study; eddy covariance; evapotranspiration; grass; growing season; maize; Penman-Monteith equation; China; Medicago sativa; Zea mays |
| 来源期刊 | Agricultural Water Management
 |
| 来源机构 | 中国科学院西北生态环境资源研究院 |
| 文献类型 | 期刊论文 |
| 条目标识符 | http://gcip.llas.ac.cn/handle/2XKMVOVA/77225 |
| 推荐引用方式 GB/T 7714 | Ji X.B.； Chen J.M.； Zhao W.Z.； Kang E.S.； Jin B.W.； Xu S.Q.. Comparison of hourly and daily Penman-Monteith grass- and alfalfa-reference evapotranspiration equations and crop coefficients for maize under arid climatic conditions[J]. 中国科学院西北生态环境资源研究院,2017,192. |
| APA | Ji X.B.； Chen J.M.； Zhao W.Z.； Kang E.S.； Jin B.W.； Xu S.Q..(2017).Comparison of hourly and daily Penman-Monteith grass- and alfalfa-reference evapotranspiration equations and crop coefficients for maize under arid climatic conditions.Agricultural Water Management,192. |
| MLA | Ji X.B.； Chen J.M.； Zhao W.Z.； Kang E.S.； Jin B.W.； Xu S.Q.."Comparison of hourly and daily Penman-Monteith grass- and alfalfa-reference evapotranspiration equations and crop coefficients for maize under arid climatic conditions".Agricultural Water Management 192(2017). |
| 条目包含的文件 | 条目无相关文件。 | |||||
除非特别说明，本系统中所有内容都受版权保护，并保留所有权利。
