The ongoing climate change, which is threatening grassland agroecosystems throughout Europe, is also evident in the Italian grasslands. These systems, often located in marginal areas, are species-rich ecosystems characterized by variable, and often unreliable, grass and forage production and strongly dependent on interactions between climate, soil and agricultural management practices (e.g. land abandonment, lack of investments on innovation, stocking rates reduction, etc.), making them very sensitive and vulnerable to climate change. This review draws from the scientific literature the impacts of current and expected climatic changes on grassland and forage crop systems framed in three different bio-climatic zones of Italy, namely the Alpine, Continental and Mediterranean, and focussing on: i) grassland biodiversity and vegetation; and ii) forage production and quality. The main aims of this review are to: i) revise the existing literature in the domain, highlighting different or common trends among different Italian biogeographical regions; ii) provide information on the main climatic impacts analysed and drivers involved in the studied evolutions; and iii) point out the knowledge gaps currently pending in order to hypothesize the future scenarios of research in this sector. Even if this review has pointed out differences in approaches, adopted methodologies and purposes of conducted researches, some common trends can be highlighted, though located in three different environments. Expected warming and modification on rainfall pattern will produce deep changes in vegetation of grassland types, with reduction or the disappearance of cold tolerant species and a spread of xeric/thermophilus ones and shrubby vegetation and with a general upward shift of vegetation types in mountain areas. Moreover, a general reduction of aboveground biomass is expected, as summer droughts is considered a main driver able to force grassland productivity. Finally, warming and rainfall reduction are considered the main factors able to reduce forage quality and palatability of grasslands, as a consequence of reduction of nitrogen content in the available biomass and of the higher spread of less unpalatable species and shrubs. The hypothesis is that the information gained from this review can provide insights on the current level of knowledge on the expected impacts of climate change on Italian grassland systems, and support the development of policy strategies for adaptation at national level.

Highlights
- This review highlights grassland systems responses to climate change in the Alpine, Apennine and Mediterranean areas of Italy.
- Future climate will determine deep changes in grassland composition, extension and productivity. 
- Droughts is considered the main factor affecting forage quality and palatability.
- Further research is needed to understand climate change impacts on grassland vegetation in the Mediterranean.

持续的气候变化威胁着整个欧洲的草原农业生态系统，在意大利草原上也很明显。这些系统通常位于边缘地区，是物种丰富的生态系统，其特点是草料生产多变且往往不可靠，并且强烈依赖气候、土壤和农业管理实践之间的相互作用（例如，土地遗弃、缺乏创新投资） , 备货率降低等.)，使他们对气候变化非常敏感和脆弱。本综述从科学文献中汲取了当前和预期的气候变化对意大利三个不同生物气候区（即阿尔卑斯、大陆和地中海）中的草地和饲料作物系统的影响，并重点关注：i) 草地生物多样性和植被; ii) 草料生产和质量。本综述的主要目的是：i) 修订该领域的现有文献，突出意大利不同生物地理区域之间的不同或共同趋势；ii) 提供有关分析的主要气候影响和参与研究演变的驱动因素的信息；iii) 指出当前悬而未决的知识差距，以假设该领域的未来研究情景。即使这篇评论指出了研究方法、采用的方法和目的的差异，但仍可以强调一些共同的趋势，尽管它们位于三个不同的环境中。预期变暖和降雨模式的改变将导致草原类型植被发生深刻变化，耐寒物种减少或消失，干旱/嗜热物种和灌木植被蔓延，山区植被类型普遍上移。此外，预计地上生物量将普遍减少，因为夏季干旱被认为是能够推动草原生产力的主要驱动因素。最后，气候变暖和降雨减少被认为是降低草原牧草质量和适口性的主要因素，由于可用生物量中氮含量的减少以及不太难吃的物种和灌木的广泛分布。假设是，从这次审查中获得的信息可以提供有关气候变化对意大利草原系统的预期影响的当前知识水平的见解，并支持制定国家层面的适应政策战略。

亮点
- 该评论重点介绍了意大利高山、亚平宁和地中海地区的草原系统对气候变化的响应。
- 未来气候将决定草原构成、延伸和生产力的深刻变化。 
- 干旱被认为是影响草料质量和适口性的主要因素。
- 需要进一步研究以了解气候变化对地中海草原植被的影响。