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Urbanization and agricultural activities are increasingly threatening karstic systems and the water resources they provide, which are crucial for the livelihood of rural communities. Over the past decade, the Río Grande de Comitán-Lagos de Montebello (RGC-LM) watershed in Chiapas, Mexico, has experienced significant deterioration in water quality. The objective of this study was to analyze the water quality dynamics within the RGC-LM watershed and their potential interaction with land use change. We conducted assessments of the physicochemical and microbiological parameters across the lotic and lentic systems within the watershed over eight monitoring campaigns (from 2013 to 2020). Cluster Analysis (CA) and Principal Component Analysis (PCA) statistical approaches were performed to identify the main drivers of surface water quality variability. This approach aims to enhance water quality assessments within environmental management strategies, with the goal of promoting sustainable land-use practices aimed at protecting and improving water resources within the watershed. Our findings indicate that there is a substantial difference between the upper and lower watershed water quality. The good water quality conditions observed in the higher altitude lakes (mountain lakes) can be attributed to favorable topographical features, specific land use patterns, and effective conservation measures. In contrast, the lotic system in the middle watershed and the lentic water bodies located at lower altitudes (plain lakes) exhibit signs of water quality degradation due to inefficient wastewater treatment and agricultural runoff. This study highlights the importance of implementing adequate environmental management strategies to address these water quality challenges effectively. Given the pressing issue of water quality degradation in karstic environments, we emphasize on the need for increased monitoring frequency of both physicochemical and microbiological parameters to capture seasonal variations and to further understand the vulnerability of water resources in karstic environments. Future assessment of nutrient concentrations, pesticide levels, and blue-green algae populations will also be crucial for evaluating the trophic state at a watershed scale.

Rivers are aquatic systems with a unidirectional flow. These systems are highly diverse habitats that support a great variety of organisms, which vary in shape and function, and sustain a diverse range of hydrological ecosystem services (HESs). The HESs provided by rivers varies based on complex hydro-geomorphological dynamics and their relationship with the functional processes of the basin. Land use changes in transition zones, where ecosystem functions are compromised, affect the basin, especially basins close to or on the periphery of urban areas. Such is the case for Mexico City, where 60 m3 of water is consumed per second, 30% of which is imported from outside sources. The rivers of the Magdalena–Eslava sub-basin are among the few remaining surficial water sources in Mexico City. These rivers are located in an area classified as a Soil Conservation Zone, which has been intensely managed for decades. The aims of this paper are (1) to perform a hydrological evaluation of two urban streams and identify their relationship with the provision of hydrological ecosystem services via (i) a hydraulic balance analysis, (ii) a hydro-geomorphological characterization of each stream, (iii) an estimate of present and potential hydraulic erosion, (iv) the determination of physicochemical and bacteriological parameters and (v) a description of macroinvertebrates, macroalgae and their habitats in order to (2) identify the impacts of socio-economic dynamics on the responses of this rural-urban lotic system. Our results show that water flow, forest cover and hydro-geomorphologic heterogeneity are key to sustaining ecosystem functioning, especially in the high and middle sections of the basin. The highest potential provision of water for direct use was recorded in the sub-basin’s middle section; however, the stream channels in that section have lost their natural water flow due to a water management infrastructure built to regulate flow during the rainy season. This intervention can be viewed as a regulation of HESs as water management infrastructure alters the transport of sediment and reduces available natural habitat. The provision of quality water in the lower area of the sub-basin has been seriously compromised by the establishment of illegal urban settlements. A relationship between biologically diverse ecological traits and their response capabilities was established and can be considered an indicator of current HES potential. Therefore, this sub-basin may constitute an example of good management and maximizing potential HESs in an urban-rural setting based on improved management strategies that could be applied in other developing nations.

Abstract Background Bacteria used as indicators for pathogenic microorganisms in water are not considered adequate as enteric virus indicators. Surface water from a tropical high-altitude system located in Mexico City that receives rainwater, treated and non-treated wastewater used for irrigation, and groundwater used for drinking, was studied. Methods The presence of enterovirus, rotavirus, astrovirus, coliphage, coliform bacteria, and enterococci was determined during annual cycles in 2001 and 2002. Enteric viruses in concentrated water samples were detected by reverse transcriptase-polymerase chain reaction (RT-PCR). Coliphages were detected using the double agar layer method. Bacteria analyses of the water samples were carried out by membrane filtration. Results The presence of viruses and bacteria in the water used for irrigation showed no relationship between current bacterial indicator detection and viral presence. Coliphages showed strong association with indicator bacteria and enterovirus, but weak association with other enteric viruses. Enterovirus and rotavirus showed significant seasonal differences in water used for irrigation, although this was not clear for astrovirus. Conclusion Coliphages proved to be adequate faecal pollution indicators for the irrigation water studied. Viral presence in this tropical high-altitude system showed a similar trend to data previously reported for temperate zones.

Several cities are facing water emergencies related to urbanization impact and amplified by climate change. Most of the cities have responded to these crises through short-term measures. However, some cities have incorporated a watershed approach to water management in seeking more sustainable solutions. Although the importance of a watershed approach in land management is generally acknowledged, studies on this topic have typically focused on theoretical models, water management in rural areas or single case-studies of cities or countries. In this research, a scoping review of the literature was performed, based on the PRISMA 2020 statement, in three databases: Web of Science, Google Scholar and SciELO. Forty-one studies were identified analyzing 17 city cases implementing urban actions from a watershed approach in water management. These cities were from the Global North and Asian rising world powers. The lack of results of cities from the Global South, based on the research undertaken, was the main limitation and bias identified. Most of the Global South results identified in this research were theoretical models, scenarios and cases of rural areas instead of urban contexts. The results obtained indicate that the main motivations for cities to implement a watershed approach were water scarcity, floods and contamination of water bodies. The implemented actions focused on the shift from gray to green and blue infrastructure and on conservation measures. Lastly, the challenges to introduce those actions were mainly the lack of economic investment, insufficient experience, stakeholder opposition, and regulatory obstacles. Urban water management could be seen as an opportunity to change the way we relate to urban territory. Incorporating a watershed approach into urban planning and water management could promote more sustainable cities. [ABSTRACT FROM AUTHOR]

The world is facing a major pulse of ecological and social changes that may favor the risk of zoonotic outbreaks. Such risk facilitation may occur through the modification of the host's community diversity and structure, leading to an increase in pathogen reservoirs and the contact rate between these reservoirs and humans. Here, we examined whether anthropization alters the relative abundance and richness of zoonotic reservoir and non-reservoir rodents in three Socio-Ecological Systems. We hypothesized that anthropization increases the relative abundance and richness of rodent reservoirs while decreasing non-reservoir species. We first developed an Anthropization index based on 15 quantitative socio-ecological variables classified into five groups: 1) Vegetation type, 2) Urbanization degree, 3) Water quality, 4) Potential contaminant sources, and 5) Others. We then monitored rodent communities in three regions of Northwestern Mexico (Baja California, Chihuahua, and Sonora). A total of 683 rodents of 14 genera and 27 species were captured, nine of which have been identified as reservoirs of zoonotic pathogens (359 individuals, 53%). In all regions, we found that as anthropization increased, the relative abundance of reservoir rodents increased; in contrast, the relative abundance of non-reservoir rodents decreased. In Sonora, reservoir richness increased with increasing anthropization, while in Baja California and Chihuahua non-reservoir richness decreased as anthropization increased. We also found a significant positive relationship between the anthropization degree and the abundance of house mice (Mus musculus) and deer mice (Peromyscus maniculatus), the most abundant reservoir species in the study. These findings support the hypothesis that reservoir species of zoonotic pathogens increase their abundance in disturbed environments, which may increase the risk of pathogen exposure to humans, while anthropization creates an environmental filtering that promotes the local extinction of non-reservoir species. [ABSTRACT FROM AUTHOR]

Purpose: The authors describe the challenges and opportunities associated with developing an interdisciplinary sustainability programme in an emerging economy and illustrate how these are addressed through the approach taken for the development of the first postgraduate programme (MSc and PhD) in sustainability science at the National Autonomous University of Mexico (UNAM). The purpose of this paper is to outline an approach that has a potential for application in other parts of Latin America and perhaps more broadly in other world regions sharing some of the same challenges and opportunities as found in Mexico. Design/Methodology/Approach: The implemented collaborative framework enabled a transformation of disciplinary research and teaching at UNAM into a postgraduate programme designed to generate cutting-edge educational and research capabilities. The approach to curriculum and programme design emphasized the process and methodological framework for curriculum development as much as the outcome itself. It entailed three primary elements: theory on collaborative processes; the curriculum design approach; and a formative and summative evaluation. Findings: Several of the challenges faced were related to the nature of the institution (mainly because of the complexity of its organization and the emphasis in maintaining disciplinary boundaries), as well as to the curriculum development and design approach (acceptance of a competency-based programme appropriate for the MSc but considered restrictive for the PhD). The experience the authors relate in this paper exemplifies how to cope with such challenges. The approach enabled the emergence of a shared vision that was appropriated by all the participants. This ultimately empowered them in the presentation of the curriculum to their disciplinary peers. Furthermore, the approach facilitated the creation of a programme that remained salient along the process, while increasingly gained legitimacy and credibility among the academic community. Social Implications: In Mexico, the number of sustainability practitioners and scientists is still insufficient, and there is a clear lack of capacities in key themes and tools. UNAM combines a strong scientific tradition and a foundational mandate to serve both the country and humanity and is, thus, a natural platform for developing a higher education programme in sustainability science. The approach taken in the development of UNAM's programme has useful lessons for the development of similar programmes in other developing nations facing similar educational and institutional challenges. Originality/Value: This model not only resulted in an innovative and novel programme in sustainability education but also, in the process, strengthened the competencies of diverse stakeholders through a systematic collaborative framework that fosters sustainability as a social learning process. Such experience illustrates the advantages of implementing a collaborative approach to enable the emergence of a critical mass capable to handle the diversity presupposed by a curriculum in sustainability science. It also shows how such a collaborative process can be implemented to overcome the limited resources, lack of experience in sustainability education and strong disciplinary focus that hampers the advancement of higher education in institutions similar to UNAM.

Water quality monitoring networks in the global south often display inefficiencies because monitoring strategies are frequently designed based on subjective professional judgments to define the temporal and spatial attributes of the networks, leading to poor cost–benefit relationships. The Lerma-Santiago Hydrological System (LSHS) in Mexico currently experiences severe environmental degradation caused by uncontrolled pollutant emissions from urban centers, agricultural, livestock, and industrial activities settled in the basin. While both the national and state authorities monitor this hydrological system, there has never been an effort to assess the monitoring efficiency of these two networks. The aim of the present study was to assess through multivariate statistical analyses the potential for coordination between these two interacting networks. For this purpose, two independent large water quality datasets with temporal and spatial attributes measured by two different authorities (the federal and the state) were used to identify those sites where coordination should be rationalized and those parameters that should continue to be monitored. The case study herein presented highlights the duplication in efforts to monitor surface water quality in the Lerma-Santiago hydrologic system, which implies a lack of coordination between the authorities and shows that water quality monitoring networks have not been reassessed since they were first implemented. Furthermore, using the case study of the Lerma-Santiago in Mexico, we expanded on various deficiencies, such as the use of different sampling frequencies and analytical methods by the authorities and inefficient communication among federal and state authorities. This study has revealed a large potential for coordinating two water quality monitoring networks (WQMN) in the Lerma-Santiago Hydrological System and a methodological approach that may be used to assess this potential. Coordination strategies for WQMNs can lead to significant cost reductions, extended network reach, and higher overall data quality in developing countries with limited financial resources and technical capabilities. [ABSTRACT FROM AUTHOR]