Environmental flow assessment for rivers feeding a coastal wetland complex in the Pacific coast of northwest Mexico

Abstract

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.

What Do Environmental Flows Mean for Long-term Freshwater Ecosystems’ Protection? Assessment of the Mexican Water Reserves for the Environment Program

“…Eflows from 278 EWR in 10 hydrological regions (HR) were assessed [32][33][34][35][36][37][38][39][40][41]: Lerm Santiago (HR code 12), Río Ameca ( 14 This novel frequency-of-occurrence-based approach for low flows and flood regime eflow components was also chosen because of its potential for managing freshwater and riparian species exposure to each-time-more intensely extreme conditions, and it contributes to addressing the non-stationarity challenge of the flow regime variability by managing resilience within the limits allowed by the biodiversity [11,22,[48][49][50][51][52][53][54]. Another reason for the selection of this method was because, among the desktop-based ones provided by the Mexican Norm, this reaches the highest detail of analysis and, therefore, it has been systematically implemented throughout the country; furthermore, consistency of outcomes has been proved when they were examined against a holistic method [21,[55][56][57][58][59][60][61]. Throughout the article, eflow assessment results from a holistic expert panel for the case of the Usumacinta river are presented to exemplify an evaluation in detail based on the Mexican Standard's Appendix F (Box 1 further in this Section; Boxes 2-4 in Sections 3 and 4).…”

Cambio de cobertura y uso de suelo en llanura costera asociados a procesos antropogénicos: caso San Blas, Nayarit

“…La camaronicultura presentó mayor aumento entre el periodo de estudio de 2000-2019, resultando las zonas inundables e indirectamente el manglar las coberturas más afectadas (23.2% de las zonas inundables que se transformaron a camaronicultura y 24.8% del manglar a zonas inundables). Este comportamiento ya había sido registrado en periodos pasados desde 1973; el incremento de la construcción de granjas camaroneras se dio entre los años 1997 y 2000 y entre los años 2009 y 2013 según lo documentado por distintos autores (Ortiz y Romo, 1994;Ramírez-García et al, 1998;Hernández et al, 2019). Sin tomar en cuenta generadores de cambio, es probable que esta tendencia se mantenga para el 2038, lo que significaría una reducción de 8.3% de la cobertura manglar entre el 2000 y lo estimado para el 2038.…”

“…Se observó un cambio en la línea de costa en la desembocadura del río Santiago, lo que figura ser intromisión del mar en área terrestre con una pérdida total de 358.9 ha, entre 2000 y 2019. Se tienen antecedentes de este mismo comportamiento en el periodo 1973-1993(Ortiz y Romo, 1994Ramírez-García et al, 1998;Hernández et al, 2019), no obstante, se recomienda realizar estudios puntuales para detectar causas y patrones de variación.…”

The Assessment of Hydrological Availability and the Payment for Ecosystem Services: A Pilot Study in a Brazilian Headwater Catchment

“…That is the unit where the land use and land cover are best managed [24][25][26][27][28]. Research studies on water availability [29][30][31][32][33][34][35] and flow distribution [36][37][38][39][40][41][42] within this unit contribute to manage water scarcity or stress, understand availability and demand, establish grants, identify environmental impacts, and even implement public policies [43][44][45][46][47][48].…”