Gao Yulian, Yue Yaojie, Yang Wuqiong
Key Laboratory of Environmental Change and Natural Disasters of Chinese Ministry of Education, Faculty of Geographical Science, Beijing Normal University, Beijing, 100875, China.
Heliyon. 2024 Jun 14;10(12):e32745. doi: 10.1016/j.heliyon.2024.e32745. eCollection 2024 Jun 30.
Irrigation plays a crucial role in enhancing agricultural productivity. The spatiotemporal variability and correlation between historical irrigation and grain yield not only illuminate existing challenges in irrigation, but also offer valuable insights for formulating effective irrigation strategies, which have been previously overlooked. Taking the North China Plain (NCP) as a case study, this study aims to elucidate regional divergence patterns and the dynamic evolution of the spatiotemporal relationship between grain yield and irrigation through time series analysis, GIS spatial analysis, and geographically weighted regression (GWR). The findings reveal that grain yields are higher in the northern regions of NCP compared to the southern regions, with significant variations among prefecture-level cities; maize yields slightly surpass wheat yields. Moreover, there has been a noticeable decrease in irrigation across approximately 49 % of the areas since 2004. Spatial autocorrelation analysis indicates clear spatial aggregation for both grains yields and irrigation. The coupled correlation between wheat yield and effective irrigation has shown a slight increase from 1990 to 2015, while that of maize has significantly decreased. The positive impact of irrigation on grain yield has nearly vanished since 2002. It is recommended to implement sprinkler irrigation in low-yield, low-irrigation areas in the south; deficit irrigation and water-saving technologies may benefit regions with medium yield and negative correlation with irrigation in central parts; maintaining current irrigation strategies is suggested for high-yield and high-irrigation regions. Additionally, relying solely on irrigation to boost yields is unsustainable; it is critical to adopt a combination of agricultural management practices along with planting high water-utilization efficient crop varieties. This study underscores the significance of developing rational irrigational strategies based on a comprehensive understanding of the intricate relationship between irrigation and grain yields-ensuring food security while sustaining agricultural water utilization.
灌溉在提高农业生产力方面发挥着关键作用。历史灌溉与粮食产量之间的时空变异性和相关性不仅揭示了灌溉方面现存的挑战，还为制定有效的灌溉策略提供了宝贵见解，而这些见解此前一直被忽视。本研究以华北平原（NCP）为例，旨在通过时间序列分析、GIS空间分析和地理加权回归（GWR）阐明粮食产量与灌溉之间时空关系的区域差异模式及其动态演变。研究结果表明，与南部地区相比，华北平原北部地区的粮食产量更高，地级市之间存在显著差异；玉米产量略高于小麦产量。此外，自2004年以来，约49%的地区灌溉量明显减少。空间自相关分析表明，粮食产量和灌溉量均呈现明显的空间聚集。1990年至2015年期间，小麦产量与有效灌溉之间的耦合相关性略有增加，而玉米的耦合相关性则显著下降。自2002年以来，灌溉对粮食产量的积极影响几乎消失。建议在南部低产、低灌溉地区实施喷灌；亏缺灌溉和节水技术可能有利于中部地区产量中等且与灌溉呈负相关的地区；对于高产、高灌溉地区，建议维持当前的灌溉策略。此外，单纯依靠灌溉来提高产量是不可持续的；采用农业管理措施与种植高效节水作物品种相结合至关重要。本研究强调了在全面理解灌溉与粮食产量之间复杂关系的基础上制定合理灌溉策略的重要性，以确保粮食安全并维持农业用水。
