Hydrological variability is one of the main drivers for rivers structure, and functionality, making the environmental flow (EF) assessment a key element to understand some ecological processes depending on it. Therefore, we aimed to evaluate the EF regime for the main rivers feeding a coastal wetland complex in northwest Mexico, following the hydrologic methodology officially approved by the Mexican National Water Commission based on daily data series (1975–2014). A mean annual runoff around 11 556 Mm3 was estimated to feed the Marismas Nacionales (MN) wetlands system from the discharge of seven rivers. It is expected that the estimated flows, regarded as necessary for the MN system to function properly as a whole, will change because of regional hydraulic infrastructure plans, threatening the discharge of the San Pedro and Baluarte rivers by reducing the flow significantly with negative effects on the MN wetlands.

Los bosques tropicales caducifolios son de los ecosistemas más vulnerables y desprotegidos de México. En la actualidad solo permanece 30% de la cobertura original y únicamente 0.2% de esta se encuentra bajo algún estatus de protección. Con el fin de aportar elementos que promuevan la conservación y manejo de estos ecosistemas, este estudio tuvo como objetivo describir la estacionalidad y las tendencias de cambio del bosque tropical caducifolio de la cuenca Piaxtla-Elota-Quelite y del área de protección de flora y fauna Meseta de Cacaxtla en el estado de Sinaloa en el noroeste de México. Para esto, se descompuso una serie de tiempo mensual de 2001 a 2016 del índice de vegetación de diferencia normalizada del satélite Modis Terra con un análisis de componentes principales con dos orientaciones. En el periodo analizado, 99% de la variación del dosel del bosque se debió a un ciclo fenológico vegetativo en el que el máximo vigor de la vegetación ocurrió en septiembre, entre tres y cuatro meses después del inicio de la temporada de lluvias. Asimismo, no se identificaron procesos de deforestación o reforestación del bosque dentro de la cuenca. La Meseta de Cacaxtla, aunque quizás de manera circunstancial, ha cumplido la función de proteger sus bosques; el buen estado de conservación en toda la cuenca podría ser un aliciente para ampliar los límites del área natural protegida y aumentar el porcentaje de bosque tropical caducifolio bajo estatus de protección en Sinaloa, que actualmente es de 0.02%.

Wetlands are recognized for their socio-environmental value and capacity to provide ecosystem services (ES) and are vulnerable to diverse threats, including those derived from climate change (CC). However, changes in ES delivery may not be recognized by ES users. To determine the extent to which coastal communities in northwestern Mexico are aware of the presence and importance of coastal wetlands, participatory workshops that followed the Metaplan methodology were held in four communities. The effects produced by extreme rainfall events (considered manifestations of CC) on wetlands and their ES were also analyzed. Four coastal wetland types (estuaries, saltmarshes, mangroves, and lagoons) were perceived to be the most important ecosystems, while poor fishing practices, mangrove deforestation, and pollution were identified as their main threats. Climate change, land use changes, and water mismanagement were also perceived as wetland threats. There were a few differences among communities that were mostly related to the number of ES and the ES categories identified. Nonetheless, saltmarshes and mangroves were identified as priority wetlands in the communities included in this study, and their ES were recognized. Most of the participants in all communities agreed on the main threats facing wetlands and their ES, particularly those related to CC and those that affect their livelihoods. Despite this awareness, regional coastal wetlands continue to decline. As such, participatory methodologies are needed to firmly establish the importance of wetlands within communities. In doing so, alternative actions based on traditional knowledge can be integrated into management actions, and novel solutions may be developed at the community level that can be scaled regionally.

Coastal wetlands are critical ecosystems that are under intense pressure due to anthropogenic activities. In addition to urban growth and agriculture, shrimp farming has become one of the main drivers behind the loss of tropical and subtropical coastal wetlands. Despite its socio-economic importance, shrimp farming has high environmental costs worldwide. Consequently, it is essential to monitor shrimp farming at regional and local scales to determine if the resulting pressure on coastal wetlands is increasing. We analyzed land use/land cover (LULC) in the Bahía Santa Maria-La Reforma (BSMR) lagoon system in northwestern Mexico using remote sensing data to determine landscape and surface cover changes. We also projected future scenarios based on stochastic models and evaluated landscape metrics considering the effects of shrimp farming. Four LULC thematic maps (1985, 1994, 2002, and 2017) with overall accuracy values > 80% and two projected maps (2027 and 2037) were produced. Agriculture was the dominant LULC class in the BSMR coastal lagoon system, although saltmarshes appear as the most critical wetland type in the area. Shrimp farming, which was nonexistent in 1985, represented 4% of the total landscape in 2017. By 2037, this value is expected to increase to 5%. Saltmarshes showed negative trends due to the expansion of shrimp farming. Considering the importance of wetlands given their ecosystem services, this study highlights LULC changes due to economic activities and the need to improve management strategies to protect the wetlands of the BSMR coastal lagoon system.