The Guadalhorce River mouth (Málaga, Southern Spain) was channelized between 1997 and 2003 to reduce flooding potential in adjacent densely populated sections of Málaga. The channel was bifurcated near the Mediterranean Sea, surrounding an isolated wetland complex composed of eight different ponds. Groundwater-level and wetland-stage data, combined with water-chemistry data from wells and wetlands, collected since 1977, have documented the hydrological and ecological responses to channelization. The results show that channelization has extended the tidal influence inland from the Mediterranean Sea through the Guadalhorce River and the subjacent coastal aquifers, producing a change in groundwater hydrodynamics. The isolation of the wetlands resulting from channelization has provoked a significant salinization of both surface water and groundwater, the extent of which varies among wetlands. These decadal-scale changes in water chemistry have promoted the appearance or increase of halophilic vegetation and have caused a shift from diving birds to predominantly shorebirds in some wetlands. Documentation of these unexpected ecosystem responses is a necessary first step for land managers who need to consider groundwater and surface water as a single resource, particularly in groundwater-dependent ecosystems along the densely populated and ecologically sensitive Mediterranean coastal areas.

瓜达尔霍斯河口（西班牙南部马拉加）在1997年至2003年之间进行了渠道化工程，以减少邻近的马拉加人口稠密地区的洪灾潜力。该航道在地中海附近分叉，围绕着由八个不同池塘组成的孤立的湿地综合体。自1977年以来收集的地下水位和湿地阶段数据与井和湿地的水化学数据相结合，记录了对渠道化的水文和生态响应。结果表明，渠道化已将潮汐影响从地中海扩展到了瓜达霍斯河和邻近的沿海含水层，从地中海向内陆扩展，从而改变了地下水的水动力。通道化造成的湿地隔离导致地表水和地下水都显着盐化，其程度因湿地而异。水化学的年代际变化已经促进了嗜盐植被的出现或增加，并导致在某些湿地中从潜水鸟向主要是水鸟的转变。对于需要将地下水和地表水视为单一资源的土地管理者，尤其是在人口稠密且对生态敏感的地中海沿岸地区依赖地下水的生态系统中，记录这些无法预料的生态系统响应是必要的第一步。