As the impact of climate change on the agricultural sector has begun to manifest itself in its severity, adaptation planning has come under scrutiny for favoring the preservation of status-quo conditions over more substantial changes. The uptake of transformational adaptations, involving a significant re-structuring of the agricultural system, is however hindered by a lack of assessment tools capable of quantifying the effects of these often more complex, far-reaching, and unprecedented changes. Agent-based models can simulate decision processes and multi-level feedbacks between system components and may therefore illustrate how transformational adaptations emerge and help identify cases where their implementation is necessary and desirable. We explore this modelling potential and aim to quantify (1) how climate change, farmer behavior and water policies may influence strategic adaptation decision-making at the farm-level, (2) the extent to which implemented adaptations represent transformations, and (3) their impact on farm structure and wider socio-ecological change. We investigate these aims through a case study of crop farming systems in the drought-prone historical region of Romagna (NE Italy), integrating insight from stakeholder interviews, local reports, spatially-explicit biophysical data and behavioral theory in the construction of an agent-based model. Results show that, on average, more than half of all implemented adaptations are transformations, thereby requiring important social and financial investments from farmers. The number of implemented transformations is highest in scenarios where drought risk perception among farmers is more widespread, notably in scenarios simulating drier climates, more adaptive behaviors and policies promoting greater water use efficiency. Under higher drought risk perception, farmers are motivated to explore a broader set of adaptations, including those outside of the trajectory determined by their farming strategy. This process particularly favors the implementation of transformational increases in farm size and irrigated area, eventually stimulating farmers to adopt an expansionist strategy. Regionally, these adaptations lead to the smallest decline in agricultural extent with fewest, yet highest profit-earning farmers, largely exacerbating presently occurring trends. Under policy scenarios simulating increased irrigation availability, fewer farmers initially experience drought and therefore perceive a drought risk. Consequently, fewer farmers undertake transformational adaptations and switch from a contractive to an expansive strategy, culminating in a relatively smaller and less profitable agricultural extent despite a larger farmer population. As transformative changes to farming strategy trigger farmers to engage in new path-dependencies, aims of water policies may therefore rebound into unintended effects, emphasizing the importance of accounting for transformational perspectives.

随着气候变化对农业部门的影响开始显现其严重性，适应性计划已受到审查，因为他们主张维持现状而不是更实质性的变化。但是，由于缺乏能够量化这些往往更为复杂，影响深远和前所未有的变化的影响的评估工具，阻碍了采用涉及农业系统重大重组的转型适应措施。基于代理的模型可以模拟决策过程和系统组件之间的多级反馈，因此可以说明如何进行转换适应，并帮助确定必要和理想的实施案例。我们探索了这种建模潜力，旨在量化（1）气候变化如何，农民的行为和水政策可能会影响农场一级的战略适应决策；（2）实施的适应措施在多大程度上代表了转变；（3）它们对农场结构和更广泛的社会生态变化的影响。我们通过在罗马涅（Ro Italy）干旱多发历史区的农作系统进行案例研究，对这些目标进行了调查，并将利益相关者访谈，本地报告，空间明晰的生物物理数据和行为理论的见解整合到了媒介的构建中，基于模型。结果表明，平均而言，所有实施的适应措施中有一半以上是转化，因此需要农民进行重要的社会和财政投资。在农民之间普遍认识到干旱风险的情况下，实施的转化次数最多，尤其是在模拟干燥气候的场景中，更多的适应性行为和政策可以提高用水效率。在对干旱风险的认识较高的情况下，农民有动力探索更广泛的适应方法，包括其耕作策略所确定的范围以外的适应方法。这一过程特别有利于实施农场规模和灌溉面积的转型性增长，最终刺激农民采取扩张主义战略。从地区上看，这些适应措施使农业程度的下降最小，而赚钱的农民最少，但收益最高，大大加剧了目前的趋势。在模拟灌溉量增加的政策情景下，最初遭受干旱的农民人数较少，因此感到干旱的风险。所以，较少的农民进行转型适应，并从紧缩战略转向宽容战略，尽管农民人数较多，但最终农业规模相对较小，利润较低。随着对农业战略的变革性变化触发农民参与新的路径依赖，水政策的目标可能因此反弹至意想不到的效果，从而强调了考虑变革观点的重要性。