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Environ Manage. 2023 May;71(5):981-997. doi: 10.1007/s00267-022-01764-y. Epub 2022 Dec 16.
Agricultural production has economic, environmental, social and cultural consequences beyond farm boundaries, but information about these impacts is not readily available to decision makers. This study applied the land use suitability concept by carrying out an assessment of a region that has the potential for intensification of agricultural production, but where eutrophication of river and estuary receiving environments due to nitrogen enrichment is a significant issue. The assessment evaluated three indicators for each farmable land parcel in the region: productive potential (the inherent productive and economic potential of the parcel), relative contribution (the potential for the parcel to contribute nitrogen to receiving environments compared to other land parcels), and pressure (the load of nitrogen delivered to receiving environments compared to the loads that ensure environmental objectives are achieved). The assessment indicated that land with high suitability for land-use intensification in Southland is limited because areas with high productive potential and low relative contribution rarely coincide with receiving environments with low pressure. Existing data, methods and models can be used to calculate the indicators under different choices for regional land-use intensity and receiving environment objectives. However, the spatial resolution and accuracy that is achievable may preclude using assessment outputs to make land use decisions at small spatial scales such as individual farms. The study highlighted that land use suitability is not an intrinsic property of a land parcel because it is dependent on choices about land use elsewhere in the landscape and the environmental objectives, and that land use suitability is inherently subjective because of decisions that concern how indicators are combined and weighted.
农业生产除了在农场边界内产生经济、环境、社会和文化后果外，其对边界外的影响信息也不易为决策者所获取。本研究通过对一个具有农业生产集约化潜力的地区进行评估，应用土地利用适宜性概念，而该地区由于氮素富集导致河口水体富营养化是一个重大问题。该评估对该地区每一个可耕种土地块的三个指标进行了评估：生产潜力（土地固有的生产和经济潜力）、相对贡献（与其他土地块相比，该土地块向受纳环境贡献氮素的潜力）和压力（与确保环境目标实现的负荷相比，向受纳环境输送的氮负荷）。评估结果表明，南地土地利用集约化的适宜土地有限，因为具有高生产潜力和低相对贡献的地区很少与氮负荷低的受纳环境同时存在。现有的数据、方法和模型可用于计算不同区域土地利用强度和受纳环境目标下的指标。然而，实现的空间分辨率和精度可能会妨碍在小空间尺度（如单个农场）上使用评估结果来做出土地利用决策。研究结果强调，土地利用适宜性不是土地块的固有特性，因为它取决于景观中其他土地利用的选择和环境目标，而且由于涉及到如何组合和加权指标的决策，土地利用适宜性具有内在的主观性。
