Stable carbon isotope analysis is increasingly used in archaeology as an indicator of crop water status and/or water management regime. While the technique shows promise, robust modern baseline studies are required to inform and validate archaeological interpretations. Here, we test stable carbon isotope values as a crop water status proxy in a monsoonal climatic context for the first time. Specifically, we test the relationship between grain stable carbon isotope values (δ¹³C_grain), water availability, irrigation and soil type in barley (Hordeum vulgare L. (Zohary and Hopf.)) in north-west India, with the aim of deriving a locally-appropriate model for isotopic interpretation. We test this relationship across a substantial rainfall gradient (200–1000 mm/year) and find a negative logarithmic relationship between climatic water availability and δ¹³C. However, there is significant noise in the relationship, and we report δ¹³C_grain variation of over 3‰ amongst samples drawn from similar climatic contexts. Soil type, irrigation type and irrigation frequency have no clear modifying effects. We conclude that: (1) barley stable carbon isotope values can act as an archaeological water status proxy in monsoonal areas, but will be most sensitive in areas receiving <450 mm rainfall per year; and (2) it is not possible to precisely infer water management regimes. On the basis of our results, we propose guidelines for archaeological barley stable carbon isotope interpretation in north-west India and analogous monsoonal climates.

稳定的碳同位素分析在考古学中越来越多地用作作物水状况和/或水管理制度的指标。尽管这项技术显示出希望，但仍需要进行可靠的现代基线研究来告知和验证考古学解释。在这里，我们首次在季风气候环境下测试稳定的碳同位素值作为作物水的状态指标。具体而言，我们测试晶粒稳定碳同位素值之间的关系（δ ¹³ Ç_谷物），水可用性，灌溉和土壤类型在大麦（大麦L.（Zohary and Hopf。））在印度西北部，目的是推导出一个适合当地的同位素解释模型。我们测试跨实质性降雨梯度（200-1000毫米/年），这种关系并找到气候水资源供应之间δ负对数关系¹³ C.然而，在关系显著噪音，我们报告δ ¹³ C ^_谷物在相似气候背景下抽取的样本之间的差异超过3‰。土壤类型，灌溉类型和灌溉频率没有明显的改变作用。我们得出以下结论：（1）大麦稳定的碳同位素值可以在季风区充当考古水的状况代名词，但在每年降雨量小于450毫米的地区最敏感；（2）不可能精确地推断出水管理制度。根据我们的结果，我们提出了印度西北部和类似季风气候下的考古大麦稳定碳同位素解释指南。