随着社会经济的不断发展，工业化、城市化过程中形成的强大土地需求，已经对土地利用强度、方式、规模和布局等造成了深远影响，进而影响到了区域生态环境状况。有研究表明，当前存在的水土流失、土地荒漠化等生态与环境问题，都直接或间接地与土地资源的不合理利用有关。土地利用在很大程度上决定了施加于环境的压力，它与环境脆弱性一起决定了环境的质量，进行科学合理的土地利用规划，已经成为了当前土地管理的重要内容。 土地利用规划作为优化配置土地资源的重要手段，是对一定区域未来土地利用超前性的计划和安排，具有时间跨度长，影响范围广等特点；而进行土地利用规划环境影响评价，可从源头上预防或减缓规划实施对区域环境产生不利影响，避免有重大缺陷的规划方案出台实施，也是环境保护参与宏观决策的重要抓手。 土地利用规划环境合理性论证是规划环评的重要和核心内容，值得深入研究。本文在对目前国内外土地利用规划环境影响评价的研究成果以及存在问题分析总结的基础上，对土地利用规划环境合理性辨识理论及方法进行了初步探讨。主要从土地利用规划目标与定位、土地结构调整与重要用地构成，土地利用分区与重要用地布局、重点用地规模与产业发展模式等方面入手，辨析了规划实施过程中环境影响发生的驱动源（环境影响主体）；结合当前环评工作关注的重点要素和土地规划的宏观特征，探讨了生态系统稳定性、环境质量与生态功能、资源承载能力、环境风险与生态安全、环境保护目标等承接规划环境影响的载体类型与特征（环境影响受体）。通过构建环境影响识别矩阵，辨识了环境影响主体对受体的主要影响；从规划环境合理性角度出发，提出了土地利用规划环境合理性的辨识模型，明确了进行土地规划环境影响评价的基本思路，并对其评价指标体系和评价方法进行了初步探讨。最后以南通市国土资源开发利用“十一五”规划为例对该区的土地利用规划环境合理性进行了综合评价。为土地利用规划环评理论与方法的不断完善提供技术支持，促进土地利用规划环境影响评价事业的开展和进一步发展。

With the continuous development of socio-economic, the strong land demand by Industrialization and urbanization has done a far-reaching impact on the intensity, mode, scale and layout of the land, which extend their impact on regional ecological environment. Studies have shown that, current ecological and environmental problems, such as soil erosion, desertification and other, have relation to the illegal land use, directly or indirectly. Land use, to a large extent, determines the pressure imposed on the environment, which together with environmental vulnerability, determines the environment quality.Therefore, scientific and rational land use planning has been an important mission of land management. Land use planning, as a important means for optimal allocation of land resources, is to conduct the scale, tructure and layout of land resources in advance for certain region, the characteristics of long-span. Then environmental impact assessment for Land use planning should play a pivotal role in not only preventing or mitigating the impact of Land use planning on environment, but also avoiding the implementation of some planning with major defects. Also it would become an important way of the participation in decision-making of environmental protection. The identification of environmental rationality is of the important and central content of land use planning, which is worth a deep research. Based on a comprehensive review on the domestic and foreign environmental impact assessment of land use planning, this study has carried on the preliminary discussion to the identifying theory and method of environmental rationality of land use planning. The driving forces of environmental impacts caused by land use planning were identified, including the planning targets and orientation, the adjusting of land use structure, composing of some important land-use types, subareas of land using, location of some important land-use types and so on. Taking both the key factors of environmental impact assessment and the macroscopical characteristics of land use planning into account, the receiving objects of environmental impacts were analyze in this paper, including stability of ecosystem, environmental quality and ecological function, environmental risk and ecological security, as while as environmental protecting objects.The mutual relations between driving forces and receiving objects of environmental impacts were set up through identifying matrix of environment impact. From planning rationality point of view, the Index system and methods of environment impact assessment for land use planning were brought forward accordingly. Then, under the guide of these theories, an empirical research of the land use planning of Nantong City was reported, which attempted to evaluate the environmental rationality. It will be practical experience of consummate unceasingly theory and method of land use planning, and have a further development in environmental impact assessment of land use planning.