Increasing heat-stress conditions, rising evaporative demand and shifting rainfall patterns may have multifaceted impacts on Cambodia's agricultural systems, including vegetable production. Concurrently, domestic vegetable supply is highly seasonal and inadequate to meet the domestic food demand, which consequently poses risks to food security locally, particularly in rural areas. This study assesses the impact of climate change on the yields and crop water productivity (CWP) of tomato, pak choi and yard-long bean cultivated year-round under different irrigated conditions (drip, furrow and net irrigation) in Siem Reap, Cambodia. The findings of this study show a similar annual precipitation decline (-23%) when comparing the 2017–2040 and 2070–2099 periods for both Representative Concentration Pathways (RCPs 4.5 and 8.5), though with significant seasonal differences between the two climate scenarios. Increasing water and heat-stress conditions are expected to have adverse impacts on tomato plants compared to pak choi and yard-long bean, which have a much higher heat tolerance. Differing yield trends are expected depending on the transplanting/sowing date, irrigation method and RCP. In tomato, for example, a -55% yield loss is projected by the end-century (2070–2099) when transplanting in January, whereas a + 37% yield increase is expected between November and December over the same period. In addition, pak choi yield enhancements of up to +30% are projected if sowing in May under RCP 8.5 for both drip and net irrigation conditions. Similarly, higher yard-long bean yields are simulated under RCP 8.5 (+29%) compared to RCP 4.5 (+11%) for the average of all sowing dates (January to December) and irrigation methods (drip, furrow and net irrigation). In sum, the findings of this work are relevant for evidence-based decision-making and the development of projects, policies and programmes increasingly informed by simulation results from bundling climate-crop approaches to transform agriculture in response to climate change.

日益加剧的热应激条件、不断增加的蒸发需求和不断变化的降雨模式可能对柬埔寨的农业系统（包括蔬菜生产）产生多方面的影响。同时，国内蔬菜供应季节性很强，不足以满足国内粮食需求，从而对当地尤其是农村地区的粮食安全构成风险。本研究评估了气候变化对柬埔寨暹粒在不同灌溉条件（滴灌、沟灌和净灌）下全年种植的番茄、白菜和一码长豆的产量和作物水分生产力 (CWP) 的影响。在比较 2017-2040 年和 2070-2099 年两种代表性浓度路径（RCPs 4.5 和 8.5）时，本研究的结果显示出类似的年降水量下降（-23%），尽管两种气候情景之间存在显着的季节性差异。与具有更高耐热性的白菜和长豆相比，预计增加的水和热应激条件会对番茄植物产生不利影响。预计不同的产量趋势取决于移栽/播种日期、灌溉方法和 RCP。例如，在番茄中，预计到本世纪末（2070-2099 年），在 1 月份移栽时，产量损失为 -55%，而 预计 11 月至 12 月同期单产将增加 37% 。此外，如果在滴灌和净灌条件下在 RCP 8.5 下播种，预计白菜产量将增加 30%。同样，在所有播种日期（1 月至 12 月）和灌溉方法（滴灌、沟灌和网灌）的平均值下，RCP 8.5（+29%）与 RCP 4.5（+11%）相比模拟了更高的一码长豆产量. 总而言之，这项工作的结果与基于证据的决策以及项目、政策和计划的制定相关，这些项目、政策和计划越来越受到模拟结果的影响，这些模拟结果来自捆绑气候作物方法以改变农业以应对气候变化。