High Speed Rail (HSR) in Spain began in 1992 and curently has a network of about 3400 km. In this 25-year period, accessibility has progressively increased, and its spatial distribution has changed throughout the territory. This has had important implications for territorial cohesion, which is a strategic planning objective of transport infrastructures in the European Union. However, this increase in HSR has environmental impacts; among other effects, new transport infrastructures imply a loss of landscape structural connectivity. This paper has two objectives: to study the distribution and development of the changes across the territory produced by the arrival of HSR in Spain between 1990 and 2025, by looking at changes in potential accessibility and structural habitat connectivity at the national scale; and to study – at the same scale – the relationship between both variables through the cost of accessibility improvements (socioeconomic variable) in terms of the loss of structural connectivity (environmental variable). All the analyses were done using GIS-based indicators, reported in the literature to be useful at the Strategic Environmental Assessment (SEA) scale. The methodology is applied in different horizon years, namely 1990, 2007, 2016, and new proposed HSR lines to 2025 in Spain. The results show that throughout the whole period (1990−2025), accessibility improved by 74.7 % due to the extension of HSR. The most important period was 1990−2007, when the main socio-economic centres were connected by HSR, while connectivity, the environmental variable, declined by −3.4 %. The greatest connectivity loss was concentrated in 2007−2016, when the areas with the highest connectivity values in 1990 were the most affected. Our results show that a 1 % increase in accessibility implied a loss of connectivity of 0.03 % in the interval 1990−2007, while in the second period, the same 1 % increase entailed a 0.17 % loss; in the 2016−2025 scenario the value is intermediate (0.08). Our work contributes to adapting connectivity studies to the environmental assessment tiers in the transportation sector (i.e. plans, programmes and projects). Each stage has its limitations due to the lack of specific data or problems of spatial scale which must be publicly reported during environmental assessment processes. We also highlight the need for new research to establish a reliable spatial scale to assess the different effects of HSR corridors at the strategic level.

西班牙的高铁（HSR）始于1992年，目前拥有约3400公里的网络。在这25年中，无障碍环境逐步增加，其空间分布在整个领土上都发生了变化。这对领土凝聚力具有重要意义，这是欧洲联盟运输基础设施的战略规划目标。但是，高铁的增加对环境有影响；除其他影响外，新的运输基础设施意味着景观结构的连通性丧失。本文有两个目标：研究全国范围内潜在的可及性和结构性栖息地连通性的变化，研究1990年至2025年西班牙高铁抵达西班牙后所产生的变化在整个领土上的分布和发展；并以可访问性改善的成本（社会经济变量）以结构连通性的损失（环境变量）为研究对象，以相同的规模研究两个变量之间的关系。所有分析都是使用基于GIS的指标完成的，该指标在文献中已有报道，可用于战略环境评估（SEA）规模。该方法适用于不同的展望年，即1990年，2007年，2016年以及西班牙新提议的2025年高铁路线。结果表明，在整个时期（1990-2025年），由于高铁的延伸，可及性提高了74.7％。最重要的时期是1990年至2007年，当时主要的社会经济中心通过高铁相连，而环境变量的连通性下降了-3.4％。最大的连接丢失集中在2007-2016年，1990年连通性值最高的地区受影响最大。我们的结果表明，可访问性增加1％意味着1990-2007年之间的连接损失为0.03％，而在第二个阶段，同样的1％的增加则导致0.17％的损失；在2016-2025年情景中，该值为中间值（0.08）。我们的工作有助于使连通性研究适应交通部门的环境评估层（即计划，计划和项目）。由于缺乏具体数据或空间规模问题，每个阶段都有其局限性，必须在环境评估过程中公开报告。我们还强调，需要进行新的研究以建立可靠的空间规模，以评估战略层面高铁走廊的不同影响。