Article

The oldest managed aquifer recharge system in Europe: New insights from the Espino recharge channel (Sierra Nevada, southern Spain)

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Abstract

In Sierra Nevada (southern Spain), the highest mountain range in southern Europe, the application of an ancestral Integrated Water Resources Management system (IWRM), based on the conjunctive use of groundwater and surface water, provides water resources for irrigation and supply in the driest months of the year in this semiarid mountain region. Meltwater is derived from the headwaters of the mountain streams and rivers through a set of uncoated channels excavated in the ground (locally known as acequias de careo) to infiltrate at the upper part of the valleys. Water infiltrated along the acequias de careo slowly flows down the hillsides, through the weathered zone of the hard rock aquifer and the glacial and periglacial sediments. The recharge accomplished through this Managed Aquifer Recharge technique (MAR) activates numerous springs located halfway down the hillside and increases the base flow of the rivers. In this study, focused on a careo channel located on the southern slope of Sierra Nevada called Acequia de El Espino, different archaeological, sedimentological, geophysical and hydrogeological techniques are applied to determine the age and the efficiency of this ancestral example of a MAR and IWRM system. Results suggest that the acequias de careo may be the oldest MAR system in Europe, and that this MAR technique could be applied in other high mountain alpine watersheds to mitigate the effects of climate change.

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... Nevertheless, relatively little is known about the hydrological repercussions of WS&H with careo aquifer recharge channels. Most of the available information is based on research conducted in a single watershed (Barberá et al., 2018;Martos-Rosillo et al., 2019;Jódar et al., 2022a), and so far, only a few other studies in the Sierra Nevada show evidence that support those findings (Pulido-Bosch and Ben Sbih, 1995;Molina Rojas et al., 2022;Rodríguez Del Rosario et al., 2023a, 2023bMorales Sotaminga et al., 2023). Therefore, the main aim of this study is providing key knowledge regarding the careo MAR system functioning by quantifying the efficiency of such an intentional aquifer recharge system, and the role played by the MAR activities in the hydrological behaviour of a watershed on the southern slopes of the Sierra Nevada (Las Alpujarras region). ...
... These metamorphic bedrocks are generally considered "hard rocks" that have a low primary porosity, and hence low hydraulic conductivity and groundwater storage potential (Singhal, 2008). The high elevation and the steep slopes of the mountain range along with the climate conditions, have favoured physical-chemical weathering processes that generated a thin layer of up to 50 m of sediments with an intermediate to high hydraulic conductivity and groundwater storage capacity (Castillo, 1993;Martos-Rosillo et al., 2019;Barberá et al., 2018). As a result, such weathered schists may form considerable slope aquifers allowing groundwater to flow within the shallow subsurface throughout fractures and through the cavities of "loose" sediments, as has been already observed in different basins of Sierra Nevada and other alpine ranges elsewhere (e.g., Gisbert et al., 1998;Martos-Rosillo et al., 2019;Rodríguez Del Rosario et al., 2023b;Pfister et al., 2017;Paznekas and Hayashi, 2016;Hayashi, 2020). ...
... The high elevation and the steep slopes of the mountain range along with the climate conditions, have favoured physical-chemical weathering processes that generated a thin layer of up to 50 m of sediments with an intermediate to high hydraulic conductivity and groundwater storage capacity (Castillo, 1993;Martos-Rosillo et al., 2019;Barberá et al., 2018). As a result, such weathered schists may form considerable slope aquifers allowing groundwater to flow within the shallow subsurface throughout fractures and through the cavities of "loose" sediments, as has been already observed in different basins of Sierra Nevada and other alpine ranges elsewhere (e.g., Gisbert et al., 1998;Martos-Rosillo et al., 2019;Rodríguez Del Rosario et al., 2023b;Pfister et al., 2017;Paznekas and Hayashi, 2016;Hayashi, 2020). ...
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Study region: Sierra Nevada, Spain. Study focus: The local communities of the Sierra Nevada mountain range adapted to recurrent dry periods by spreading water along hillslopes with unlined channels that deviate surface runoff from headstreams during high flow periods. However, the impact of the so-called careo practice on river regimes in Sierra Nevada remains mostly unquantified. This work aimed to fill this gap by monitoring and analyzing streamflow in a major careo channel and river during three consecutive years (2021-2023) in the Mecina watershed (51 km 2 , Las Alpujarras). New hydrological insights for the region: This study reveals unexpectedly high proportions of groundwater and human influence in total basin runoff within the hard rock environment of the Sierra Nevada. The data shows consistent streamflow gains between controlled river sections despite experiencing three years of below average precipitation, most remarkably below high infiltration channel stretches. The relationship between careo recharge and river flow kept constant even during the driest of the observed years. The influence from careo recharge was most noticeable during the low flow period (summer) when it represented between 40 % and 60 % of river streamflow. In addition, about 32 % of the total recharge to the aquifer in the basin comes from water transported and infiltrated by just one of the basin's careo channels, which means that such a careo recharge channel increases the natural infiltration of meteoric water by 47 %.
... These artificial aquifer recharge systems, developed since medieval times in the high and middle mountains of the Sierra Nevada (Granada-Almería, southern Spain), are considered the oldest in Europe (Martos-Rosillo et al. 2019). Their hydrological and hydrogeological functioning has already been demonstrated. ...
... Barberá et al. (2018) demonstrated the connection between the acequias de careo, and springs and streams located downstream of the ditches (Figure 2), using hydrogeochemical and isotopic techniques in the Bérchules river basin, located west of the hydrological basin investigated in this work. Martos-Rosillo et al. (2019) and Oyonarte et al. (2022) calculated high rates of water infiltration from the acequias de careo into the aquifers., Jódar et al. (2022) demonstrated that this ancestral aquifer recharge system can double the natural recharge rates in the aquifers at the hydrological basin scale, significantly increasing the base flow of the springs located downstream of the irrigation ditches and that of the river during the summer when more water is needed for irrigation. ...
... Thus, in the Bérchules ditch the infiltration rate is 49.7 L/s/km and in the Horcajos ditch it is 21.7 L/s/km. Proceeding in the same way, the infiltration rates calculated by Oyonarte et al. (2022), are 11.3 L/s/km in the Busquístar ditch (hydrological basin of the Trevelez river) and 12.2 L/s/km (Martos-Rosillo et al. (2019) in the El Espino ditch (Bérchules river basin). For much more distant parallels, the amunas, or Peruvian acequias de careo, in which infiltration rates have been measured also present high values, despite developing on hard rocks of supposedly low permeability (Martos-Rosillo et al. 2020). ...
Article
Historical water management systems, in operation since the Islamic period (eighth to fifteenth centuries), have generated important irrigated areas and transformed the landscapes in a coevolutionary process over more than a thousand years. In the Sierra Nevada, the so-called acequias de careo stand out as a singular technical system for water recharge from the thaw. This way of managing surface- and groundwater, as well as soil and vegetation, while generating social, economic, and environmental benefits, is an example of Integrated Water Management and Nature-based Solutions. This system has proven its efficiency and resilience, having been operational since the Middle Ages. The abandonment of these water management systems is an irreparable cultural and environmental loss. The transdisciplinarity of this case study can be considered a success and a good example for its application in other geographical and cultural contexts promoting sustainable and resilience solutions based on historical socio-ecological systems and local ecological knowledge and practices.
... Indeed, since the Islamic period in the 8th century, local inhabitants have transformed the territory through the construction of a network of water ditches dug on the ground (acequias), which collect melting water from the summits and canalise it along the slopes to the villages and agricultural fields (Pulido-Bosch & Sbih 1995;Martos-Rosillo et al. 2019). This water management system increases water infiltration, recharging the aquifers and increasing the availability of water during summer. ...
... This water management system increases water infiltration, recharging the aquifers and increasing the availability of water during summer. The system also reduces soil erosion, favours the existence of flora species with higher water requirements, and makes possible agriculture in a slope area (Martos-Rosillo et al. 2019). Communities sharing irrigation sources have created management rules to ensure water equitable distribution and use. ...
... The rapid disappearance of pastures, in turn, impacts livestock, all together putting at risk the future of pastoralism in Sierra Nevada. In practical terms, this finding calls for attention to the maintenance of traditional irrigation systems, which -for centuries -have allowed the supply of water to agricultural and inhabited areas on the slopes of the mountain, while maintaining the state of the high mountain meadows during the summer, favouring a large biodiversity of wild flora, and offering water for wildlife and livestock of the local population (Pulido-Bosch & Sbih 1995;Martos-Rosillo et al. 2019). ...
... De este modo, se consigue retener el agua en los acuíferos para disponer de ella en los periodos secos. El agua sembrada es posteriormente utilizada para riego, usos domésticos, abrevaderos, etc. (Barberá et al., 2018;Martos-Rosillo et al., 2019Ochoa-Tocachi et al., 2019;Yapa, 2013Yapa, , 2016. ...
... Comparativamente, en Europa ha quedado demostrado que las acequias de careo de España permiten recargar agua en los acuíferos de ladera, reteniendo la escorrentía del deshielo en las cuencas hidrográficas en donde se practica (Barberá et al., 2018;Martos-Rosillo et al., 2020). Es importante indicar también que la vegetación, y por ende la biodiversidad, mejoran notablemente en zonas que utilizan sistemas de SyCA en comparación con sitios donde no se los implementa (Albarracín et al., 2018;Martos-Rosillo et al., 2019;Yapa, 2013). ...
... De esto se asume que al manipular los procesos hidrológicos se obtendrá un resultado en la biota. En este sentido, los sistemas de SyCA, al enfocarse en el manejo de los recursos hídricos mediante la manipulación del flujo hidrológico, evidencian con el tiempo cambios en las formaciones vegetales circundantes a las áreas intervenidas (Albarracín et al., 2021;Martos-Rosillo et al., 2019). ...
... Sobre estos materiales, y principalmente, por encima de los 2000 m de altitud, se superponen formaciones cuaternarias, compuestas fundamentalmente por materiales de tipo glaciar y periglaciar. El conjunto forma un acuífero de reducido espesor, con profundidades máximas estimadas de entre 30 y 50 m, el cual cubre en su totalidad la cuenca del Bérchules y se extiende prácticamente por todo el ámbito de Sierra Nevada (Martos-Rosillo et al., 2019b). ...
... (A) Distribución estacional de P, T, ETP, caudal promedio medido en la estación de aforo de Narila (QObs) e intervalo de variación del caudal medido asociado a los percentiles 20 % y 80 % (QInt), y caudal calculado por el modelo HBV (QCalc) (modificado de Jódar et al., 2018). (B) Distribución altitudinal de los valores promedio anuales de P, T, y ETP en la cara sur de Sierra Nevada (modificado de Jódar et al., 2017) Dada la escasez secular de recursos hídricos en las zonas aledañas a Sierra Nevada, se desarrolló ya desde la época de Al-Ándalus, con el dominio árabeberéber en el sur de la Península Ibérica del siglo VIII, un eficiente sistema de manejo y gestión del agua (Delaigue, 1995;Martos-Rosillo et al., 2019b). Para ello se construyó una extensa red de canales de infiltración, excavados en el terreno sin impermeabilizar, denominados acequias de careo (Figura 1C). ...
... La acequia pasa por algunas simas, en las que la capacidad de infiltración del terreno es más elevada, y por las que se vierte parte del agua que transporta la acequia. La acequia del Espino termina en la sima de Bérchules a cota 1820 m s.n.m. (Figura 3C), la cual consiste en una superficie cubierta de pasto, de escasa pendiente, que cubre un área de 32328 m2, y que se caracteriza por presentar un sustrato con una alta capacidad de infiltración (Martos-Rosillo et al.,2019b). De hecho, en este punto se acaba infiltrando toda el agua que le llega por la acequia, incluyendo puntas de caudal de 390 L/s medidas durante el año hidrológico 2014 y 2015, que implican tasas de infiltración superiores a 1 m/día. ...
Chapter
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Careo channels are ancestral Nature-Based Solutions for water management that are used to recharge aquifers in the watershed of the Sierra Nevada Mountain massif (Spain). These hand-dug channels divert snowmelt from the headwaters of rivers and let it infiltrate into the upper parts of the hill slopes and by that increase the water resources available during the dry season. Our study investigates the role of this ancestral aquifer recharge practice in the Bérchules watershed by comparing its yield with respect to the total recharge of the aquifer during the 2014-2015 hydrological year. For this purpose, we contrast the total recharge of 7.6 hm³, calculated with an HBV watershed model, with flow measurements we conducted in the main channels of the system during this year. Our results show that 52% of the total recharge can be accounted for a spatially distributed recharge by natural infiltration of meteoric waters, while the remaining 48 % originate from waters captured and infiltrated by careo channels. The study highlights the efficiency and importance of this ancestral aquifer recharge system developed in hard rocks, which may be replicated in other high mountain watersheds of similar hydroclimatic and geological characteristics.
... The maintenance of such a system whose maintenance may help in the ecological transition. This highly efficient system [19,20] was developed independently by local communities south of the southeast of the Iberian Peninsula and in the Andes [8,21] to solve problems regarding scarcity. This paper describes the system functioning as a Nature-based Solution for Integrated Water Resources Management (NbS-IWRM) and postulates it as an adaptation measure to climate change. ...
... The concept of Water Sowing and Harvesting (WS&H) was coined in these areas. WS&H describes the process by which surface runoff water from both snowmelt and rainfall is collected and infiltrated (sown) through a system of channels dug in the upper parts of the mountain basins (Figures 1 and 2) [19,41,42], to be recovered (harvested) elsewhere, sometime later, as a groundwater discharge, for irrigation or domestic use. The delay is due to the slow velocity of groundwater through permeable materials. ...
... In the same basin, Oyonarte et al. (2022) [14] measured for the Busquístar channel a mean infiltration rate per unit length of channel (q) of 9.32 L/s/km. In the neighboring Bérchules Basin, Martos Rosillo et al. (2019) [19] obtained aq value of 20.2 L/s/km in the Espino channel. Here, they measured infiltration rates up to 400 L/s in some channel zones. ...
Article
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Nature-Based Solutions for Integrated Water Resources Management (NbS-IWRM) involve natural, or nature-mimicking, processes used to improve water availability in quantity and quality sustainably, reduce the risks of water-related disasters, enhance adaptation to climate change and increase both biodiversity and the social-ecological system's resilience. United Nations and the European Commission promote their research as a cornerstone in the changeover to the Ecological Transition. In the Sierra Nevada range (Spain) and the Andean Cordillera, there is a par-adigmatic and ancestral example of NbS-IWRM known as "careo channels" and "amunas", respectively. They recharge slope aquifers in mountain areas and consist of an extensive network of channels that infiltrate the runoff water generated during the snow-thawing and rainy season into the upper parts of the slopes. The passage of water through the aquifers in the slope is used to regulate the water resources of the mountain areas and thus ensure the duration of water availability for the downstream local population and generate multiple ecosystem services. This form of water management is known as Water Sowing and Harvesting (WS&H). As shown in this work, it is a living example of a resilience and climate change adaptation tool that can be qualified as a nature-based solution.
... Geoelectrical analysis is widely used to characterize the geological and hydrogeological setting of an area (Guérin et al., 2001;Francese et al., 2009;Ball et al., 2010;Boiero et al., 2010;Descloitres et al., 2013;Casado et al., 2015;Kazakis et al., 2016a, b;Viguier et al., 2018;Martos-Rosillo et al., 2019;Flores-Avilés et al., 2020;Jódar et al., 2020b). The electrical resistivity tomography (ERT) was carried out using the Terrameter LS2 resistivity meter (resolution 3 nV) of 48 channels (stainless-steel electrodes) and 4 simultaneous readings. ...
... dug canals without lining solution) transporting surface water from high elevation areas down to lowlands for farming purposes can also contribute to recharge groundwater through seepages (Martos-Rosillo et al., 2020). Coupled with earlier natural recharge processes, irrigation canals also play a key role in the recharge of alluvial aquifers in mountainous arid regions (Simmers, 1997;Niswonger et al., 2017;Somers et al., 2017;Barberá et al., 2018;Bouimouass et al., 2020;Martos-Rosillo et al., 2019;Ochoa-Tocachi et al., 2019;Taucare et al., 2020a). ...
... The pre-Inca cultures developed nature-based canal systems to improve the infiltration in the hillslopes of the Peruvian Andes to secure water resources during dry periods (Ochoa-Tocachi et al., 2019). Hispano-Roman, Arab and Berbers civilizations also developed and implemented similar techniques in the Iberian Peninsula (Pulido-Bosch and Sbih, 1995;Martos-Rosillo et al., 2019). There, local farmers are fully aware of these traditional managed aquifer recharge techniques and still continue to maintain them. ...
Article
The Mountain-Block Recharge (MBR), also referred to as the hidden recharge, consists of groundwater inflows from the mountain block into adjacent alluvial aquifers. This is a significant recharge process in arid environments, but frequently discarded since it is imperceptible from the ground surface. In fault-controlled Mountain Front Zones (MFZs), the hydrogeological limit between the mountain-block and adjacent alluvial basins is complex and, consequently, the groundwater flow-paths reflect that setting. To cope with the typical low density of boreholes in MFZs hindering a proper assessment of MBR, a combined geoelectrical-gravity approach was proposed to decipher groundwater flow-paths in fault-controlled MFZs. The study took place in the semiarid Western Andean Front separating the Central Depression from the Principal Cordillera at the Aconcagua Basin (Central Chile). Our results, corroborated by field observations and compared with worldwide literature, indicate that: (i) The limit between the two domains consists of N-S-oriented faults with clay-rich core (several tens of meters width low electrical-resistivity subvertical bands) that impede the diffuse MBR. The “hidden recharge” along the Western Andean Front occurs through (ii) focused MBR processes by (ii.a) open and discrete basement faults (mass defect and springs) oblique to the MFZ that cross-cut the N-S-oriented faults, and (ii.b) high-hydraulic transmissivity alluvial corridors in canyons. Alluvial corridors host narrow unconfined mountain aquifers, which are recharged by indirect infiltration along ephemeral streams and focused inflows from oblique basement faults. This study also revealed seepage from irrigation canals highlighting their key role in the recharge of alluvial aquifers in the Central Depression. The proposed combined geophysical approach successfully incorporated (hydro)geological features and geophysical forward/inverse modelling into a robust hydrogeological conceptual model to decipher groundwater flow-paths in fault-controlled MFZs, even in the absence of direct observation points.
... According to Martos-Rosillo et al. [11], WS&H is a process through which rainwater is captured through infrastructures based on ancestral knowledge (planting when it rains) and later used through springs, wells, and drainage galleries (harvesting water during droughts). The use of rainwater through collection systems represents a viable alternative (probably the oldest) to solve access to water [61,62]. An example is the artificial recharge of aquifers through infrastructures as an alternative to the construction of water reservoirs. ...
... Among the different WS&H techniques registered globally, some authors have proven their effectiveness. For instance, Martos-Rosillo et al. [62], Oyonarte et al. [51], and Jódar et al. [66] demonstrated that irrigation ditches are techniques that allow natural water infiltration rates to double and recharge aquifers in an ancestral way. The abandonment of this system represents an irreparable cultural and environmental loss, and its potential as a sustainable water management solution based on socio-ecological systems is evident. ...
Article
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Water Sowing and Harvesting (WS&H) is an ancestral knowledge widely used as a sustainable technique in water management. This study aims to analyse the importance, promotion, and cultural heritage of WS&H techniques through a literature review in Ecuador, considering applications of ancestral techniques by region (coastal, Andean and insular) with a strengths, opportunities, weaknesses, and threats (SWOTs) analysis and a focus group for a strategy proposal of the water supply. The methodology of this study includes the following: (i) an analysis of the evolution of WS&H studies in Ecuador; (ii) a presentation of WS&H techniques and their applications; and (iii) the contribution of WS&H to the Sustainable Development Goals (SDGs), complemented by a SWOTs analysis. The results show that, in Ecuador, WS&H is a method of Nature-based Solutions (NbSs) applied to the problems of water scarcity and is affordable, ecological, and has high efficiency, improving agricultural productivity and guaranteeing water supply for human consumption. The Manglaralto coastal aquifer, a case study in the coastal region of Ecuador, involves WS&H management and artificial aquifer recharge. WS&H structures became a reference for the sustainable development of rural communities that can be replicated nationally and internationally as a resilient alternative to water scarcity and a global climate emergency, contributing to the SDGs of UNESCO.
... En el siglo VIII y siguientes, durante la dominación arábigo-bereber, en Sierra Nevada se construyó una extensa red de canales de agua, denominados acequias, para irrigar la extensa superficie de cultivos en terrazas, de generar pastos, de abastecer a la población y al ganado, de trasferir agua entre cuencas vecinas y de recargar los acuíferos. La recarga de estos acuíferos someros y en régimen de flujo libre, desarrollados sobre los esquistos y materiales periglaciares existentes en las partes altas del macizo, se hace con las denominadas acequias de careo (Martos-Rosillo et al., 2019a;2019b;Delaigue, 1995). Aunque el origen de los careos se remonta al menos al año 1139, fecha del primer documento escrito donde se menciona a las acequias de careo, su mayor utilización fue en los siglos XIII a XV, cuando se desarrolló el intrincado sistema de canalizaciones y acequias para el mayor aprovechamiento del agua (Martín Civantos, 2010;Vivas et al., 2009;Gómez-Ortiz et al., 2013;Martos-Rosillo et al., 2019). ...
... La Cuenca del Bérchules está principalmente en el Complejo Nevado-Filábride de rocas de baja permeabilidad, pero con una capa superior alterada de mayor permeabilidad en gran parte de la cuenca, en especial sobre la roca no alterada y con abundantes fisuras, y sedimentos glaciares y periglaciares cuaternarios por encima de 2000 m. El conjunto de esquistos alterados y los sedimentos cuaternarios forman un conjunto moderadamente permeable de 30 a 50 m de espesor (Martos-Rosillo et al., 2019b). Se estima que la parte saturada activa son los 10-20 m más profundos, que constituye un medio acuífero generalizado que se extiende unos 59 km 2 de los 68 km 2 de la cuenca, con límites coincidentes con los de la cuenca. ...
Chapter
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Groundwater management and governance in the alpine Berchules watershed
... 1 Introduction 8 2 Cross Sectoral Briefing 9 2.1 How can MERLIN support transformation 9 2.2 Description of the six sectors 10 2.3 Societal challenges for NbS to address 11 2.4 The need for NbS 11 2.5 Challenges to mainstreaming NbS 13 2.6 Opportunities for mainstreaming NbS 15 2.7 Reviewing our sectoral cooperation opportunities 16 2.8 Alignment with IUCN criteria for NbS 17 2.9 Implications for the MERLIN Academy 19 2.10 Next Steps 20 2.11 References 20 3 Briefing for Agriculture Sector 22 3. ...
... 1 Introduction 8 2 Cross Sectoral Briefing 9 2.1 How can MERLIN support transformation 9 2.2 Description of the six sectors 10 2.3 Societal challenges for NbS to address 11 2.4 The need for NbS 11 2.5 Challenges to mainstreaming NbS 13 2.6 Opportunities for mainstreaming NbS 15 2.7 Reviewing our sectoral cooperation opportunities 16 2.8 Alignment with IUCN criteria for NbS 17 2.9 Implications for the MERLIN Academy 19 2.10 Next Steps 20 2.11 References 20 3 Briefing for Agriculture Sector 22 3. ...
Technical Report
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MERLIN Deliverable D4.1 2 MERLIN Key messages 1. Mainstreaming aquatic restoration using Nature-based Solutions (NbS) requires involving all relevant stakeholders and understanding their connection with rivers and wetlands. We work with six economic 'MERLIN' sectors (Agriculture, Hydropower, Insurance, Navigation, Peat Extraction and Water Supply and Sanitation). 2. Our data suggests these sector actors are aware of the environmental and socioeconomic challenges arising from degraded freshwater ecosystems and are aware of the types of NbS that MERLIN will demonstrate and implement. However, not all sector actors were convinced of the need for radical change/transformation or that they could rely on NbS to deliver their sector needs. 3. The language of NbS is not well embedded (yet) with these sectors, however concepts of sustainability and working with nature are well understood. With its focus on meeting societal goals, NbS can address the sectors' concerns about balancing environment, social and economic objectives. 4. The sectors are seeking evidence regarding the benefits of NbS to their sector, concrete examples of NbS at the catchment scale and assistance to integrate sectoral concerns into spatial catchment management. 5. There are strong interdependencies and synergies between the MERLIN sectors. However, there are also potential trade-offs and challenges. We are building a Community of Practice to support an understanding of NbS, how we can enable mainstreaming of NbS in the six MERLIN sectors, and most importantly, how the sectors can work together. MERLIN Deliverable D4.1 3 MERLIN Executive Summary Our research has highlighted that there is a shared awareness that the freshwater environment is under threat and that the European Green Deal provides a supportive agenda to address these threats. In MERLIN we focus on how to mainstream freshwater restoration through Nature-based Solutions (NbS) in order to develop solutions for both nature and society, in the spirit of the Green Deal. NbS require the engagement of all relevant stakeholders including the economic sectors that affect, and are affected by, interventions in our freshwater ecosystems. We focus on Agriculture, Hydropower, Insurance, Navigation, Peat Extraction and Water Supply and Sanitation Sectors, but other sectors, including the finance sector, are also important. Our data suggests these sector actors are aware of the environmental and socioeconomic challenges arising from degraded freshwater ecosystems and are aware of the types of NbS that MERLIN will demonstrate and implement. However, not all sector actors were convinced of the need for radical change or that they could rely on NbS to deliver their sector needs. Our challenge is to illustrate how using NbS can advance the Green Deal goals, given that most actors were supportive of the overall vision. Roles and responsibilities remain unclear and some sectors (Agriculture, Hydropower, Peat Extraction) are more involved in implementing NbS within their own properties than others that mainly rely on the 'downstream' benefits (Insurance, Navigation, Water Supply and Sanitation). Some intra-and inter-sectoral tensions were identified; and there are still questions about how to support collective action at the catchment scale to coordinate different actors involved in water management and use. Sectors were concerned about how NbS will balance economic, environmental and social objectives and how 'burden-sharing' of restoring nature will be governed. There were concerns about impacts on business profitability but also about wider trade-offs e.g. with food or energy security. These are opportunities to show how true NbS address societal goals over the longer term, in ways that should help businesses become more resilient to the pressure of climate and other changes. Policies can play a stronger role in supporting NbS and integrated water management. There are also opportunities to value working with nature through certification and value chains; and to harness innovative finance to work at scale and at pace. The approach in MERLIN aligns with the IUCN principles for NbS but there is still a long way to go, due to the challenges outlined above. This is our baseline from which we will engage representatives from the six MERLIN sectors on some prioritised areas for cooperation around provision of evidence, policy and value chain recommendations, implications for social justice and networking. The MERLIN Academy can support this with resources to respond to concerns over information and training. Most importantly, we are building a Community of Practice to try to address the tensions, trade-offs and burden-sharing questions. The robust debates experienced in the development of this briefing illustrates the benefits of such a cross-sectoral and trans-disciplinary forum.
... In South America, particularly in Andean arid and semiarid regions (Yapa, 2013;Ochoa-Tocachi et al., 2019;Martos-Rosillo et al., 2020), there is a variety of ancient water sowing/harvesting systems (WSHS) to regulate aquifer recharge . They include the pre-Hispanic amunas of Peru (Ochoa-Tocachi et al., 2019), which developed independently on a different continent but resemble careo channels of Sierra Nevada in design and operation (Martos-Rosillo et al., 2019a, 2019b. In Perú, hundreds of kilometers of abandoned amunas are currently being restored (Cárdenas-Panduro, 2020), all of them in river basins that provide water to Lima. ...
... It was not until the Al-Andalus period in the 8th century that people of Arabic-Berber origin started to tackle this problem efficiently. They developed a water management system that makes use of an extensive network of water infiltration channels (Delaigue, 1995;Martos-Rosillo et al., 2019b). These hydraulic structures, locally known as acequias de careo (Fig. 1C), are relatively shallow and narrow channels dug with simple tools and strengthened with local materials, but not sealed (Espín et al., 2010). ...
Article
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The acequias de careo are ancestral water channels excavated during the early Al-Andalus period (8th–10th centuries), which are used to recharge aquifers in the watersheds of the Sierra Nevada mountain range (Southeastern Spain). The water channels are maintained by local communities, and their main function is collecting snowmelt, but also runoff from rainfall from the headwaters of river basins and distributing it throughout the upper parts of the slopes. This method of aquifer artificial recharge extends the availability of water resources in the lowlands of the river basins during the dry season when there is almost no precipitation and water demand is higher. This study investigates the contribution of the careo channels in the watershed of Bérchules concerning the total aquifer recharge during the 2014–2015 hydrological year. Several channels were gauged, and the runoff data were compared with those obtained from a semi-distributed hydrological model applied to the same hydrological basin. The natural infiltration of meteoric waters accounted for 52% of the total recharge, while the remaining 48% corresponded to water transported and infiltrated by the careo channels. In other words, the careo recharge system enhances by 92% the natural recharge to the aquifer. Our results demonstrate the importance of this ancestral and efficient channel system for recharging slope aquifers developed in hard rocks. The acequias de careo are nature-based solutions for increasing water resources availability that have contributed to a prosperous life in the Sierra Nevada. Its long history (>1200 years) suggests that the system has remarkable resilience properties, which have allowed adaptation and permance for centuries in drastically changing climatic and socioeconomic conditions. This recharge system could also be applied to —or inspire similar adaptation measures in— semi-arid mountain areas around the world where it may help in mitigating climate change effects.
... In South America, particularly in Andean arid and semiarid regions (Yapa, 2013;Ochoa-Tocachi et al., 2019;Martos-Rosillo et al., 2020), there is a variety of ancient water sowing/harvesting systems (WSHS) to regulate aquifer recharge . They include the pre-Hispanic amunas of Peru (Ochoa-Tocachi et al., 2019), which developed independently on a different continent but resemble careo channels of Sierra Nevada in design and operation (Martos-Rosillo et al., 2019a, 2019b. In Perú, hundreds of kilometers of abandoned amunas are currently being restored (Cárdenas-Panduro, 2020), all of them in river basins that provide water to Lima. ...
... It was not until the Al-Andalus period in the 8th century that people of Arabic-Berber origin started to tackle this problem efficiently. They developed a water management system that makes use of an extensive network of water infiltration channels (Delaigue, 1995;Martos-Rosillo et al., 2019b). These hydraulic structures, locally known as acequias de careo (Fig. 1C), are relatively shallow and narrow channels dug with simple tools and strengthened with local materials, but not sealed (Espín et al., 2010). ...
... More than a thousand years ago and 10,000 miles apart, local peoples in the Sierra Nevada mountains of Spain and in the Andes mountains of South America independently created ingenious nature-based technologies for managing water. In both regions, local peoples created remarkably similar cultural landscapes to manage the recharge of aquifers to address seasonal water scarcity (Fernandez Escalante et al., 2019;Martos-Rosillo et al., 2019;Ochoa-Tocachi et al., 2019) and to enhance wet pasture areas for livestock-the borreguiles in Spain and bofedales in the Andes (Martin-Civantos, 2014;Verzijl and Guerrero Quispe, 2013). Long before the era of modern hydrological science, people on both continents had a deep understanding of water, soils, vegetation, and geology-knowledge of how water moves across the landscape-and they used this knowledge to ensure water supplies during times of scarcity. ...
... In the Sierra Nevada, spring snowmelt from the high peaks fills rushing streams and rivers, but this water is largely gone by the dry Mediterranean summer. Between March and June, the traditional acequias de careo ( Fig. 13.4) use a system of irrigation channels to divert water from streams and rivers in the highlands to areas where the water can infiltrate the permeable soils and weathered bedrock, recharging groundwater (Martin-Civantos, 2014;Martos-Rosillo et al., 2019). As the subsurface water slowly moves downhill, springs and seeps lower down in the valleys are recharged and continue to flow during the dry season months. ...
Chapter
Key messages • Indigenous peoples and local communities around the world have developed nature-based, resilient, and sustainable solutions for water security based on traditional knowledge-practice-value systems. • Water sowing and harvesting technologies such as albarradas in Ecuador, sand dams in Africa, and wetland management and infiltration systems in Spain and the Andes work with nature to “sow” water for storage in soils, river sands, and groundwater, making water available for harvesting during times of water scarcity. • Integrated land and water management systems rely on managing ecosystem processes in combination with irrigation and terracing infrastructure to control the timing and supplies of water to complex agroforestry, rice or wet-pond taro cultivation, home gardens, and in some cases coastal fishponds and fisheries, as well as providing clean water for households. Predating contemporary integrated watershed and ecosystem-based management, these systems that emphasize protecting source watersheds are models of sustainably working and building with nature to manage water resources. • Continued viability of many of these practices is under threat, as Indigenous peoples and local communities remain marginalized in many countries, are under pressure from the forces of globalization, with lives and territories threatened in several places, and with traditional and Indigenous knowledge lost with the passing of older generations and forced migration. • However, these practices and the knowledge they are based on are being revitalized as Indigenous and local peoples lead movements to protect and revitalize their heritage, while scientists, conservationists, water managers, and governments increasingly recognize the value of these traditional nature-based solutions.
... These interventions to improve natural water retention capacity also help maintain ecosystem functioning and biodiversity (Collentine and Futter, 2018) and are context specific: improving sponge functioning must take into account the characteristics of soils and ground-and surface water systems under different landuses, climatic zones, geology and topographic contexts. The individual measures include improvements of farming practices and soil management strategies Sonneveld et al., 2018;Miralles-Wilhelm, 2021), stream-and soil structure to slow down, absorb and reduce runoff, innovative and traditional managed aquifer recharge (MAR) techniques (Martos-Rosillo et al., 2019), conservation and restoration of ecosystems such as forests, peatlands and wetlands, and reconnection of floodplains to provide more room for streams and river flood volumes (Iacob et al., 2014). ...
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Climate change and human-modified landscapes have led to an increase in global flood and drought risks, while biodiversity has declined. The concept of using nature-based solutions (NbS) to improve the water retention capacity at the landscape scale, also known as ‘sponge functioning of catchments,’ has been recognised to help reduce and delay peak flows and stimulate infiltration to the groundwater, thus reducing flood and drought risks. Although various effects of NbS have been demonstrated, there is limited evaluation of the combined multiple benefits for flood risk reduction, drought risk reduction, and biodiversity. To address this gap, we analysed various online databases on NbS and additional literature on the evaluated combined effects of NbS. We found that the quantitative evaluation of NbS is fragmented and not standard practice in many projects. Although many successfully implemented NbS have been reported in different environments globally, most cases lack evidence for their response to the combined impacts of floods, droughts, and biodiversity. Therefore, we propose four components to facilitate planning, design, implementation, and monitoring of NbS that improve sponge functioning for floods and droughts. First, we suggest increased understanding of how NbS affects the hydrological processes of both flood and drought events along the full range of potential conditions. Second, we recommend evaluating the effect of potential NbS measures at a landscape scale. Third, we propose that integrated modelling and upscaling techniques should be improved to quantify the impacts of NbS. Finally, we suggest using a consistent and socially relevant set of indicators to evaluate the NbS and communicate this with stakeholders. In conclusion, our analysis demonstrates a need for more comprehensive and standardised evaluation of NbS, particularly in relation to their combined impacts on floods, droughts, and biodiversity.
... The management of water resources use to avoid stresses on the groundwater compartment is being mostly attended through conjunctive use of various sources, such as surface water, groundwater, recycled water or desalinized water (Hao et al., 2022;Hashimoto et al., 2022;Portoghese et al., 2021;Sondermann and Proença de Oliveira, 2022); or through smart water use where technology (e.g., IoT -Internet of things) is incorporated in the water supply processes to use less water while getting the same or even better performances, and where the case of smart meters in irrigation is a groundbreaking example (Bwambale et al., 2022;Khachatryan et al., 2019). Finally, the restoring of groundwater storage has been accomplished mainly through managed recharge (Itani et al., 2022;Liu et al., 2022;Martinsen et al., 2022;Pavelic et al., 2022), in many cases using nature-based solutions (Jódar et al., 2022b;Jódar et al., 2022a;Martos-Rosillo et al., 2019;Ochoa-Tocachi et al., 2019;Oyonarte et al., 2022), not ruling out the necessary preoccupation with water quality if reclaimed water is used in the process Guo et al., 2023;Hübner et al., 2022;Xia et al., 2022;Zheng et al., 2023). ...
Article
Groundwater helps overcoming periods of drought buffering their effects on water supply to people, natural ecosystems and the economy. Following the latest Conference of the Parties (COP27), groundwater research gained renewed impulse because the Parties committed themselves to invest on environmental dimensions of water security related with aquifer characterization and protection. In that context, the purpose of this study was to help providing an integrated assessment to some fundamental issues about groundwater security, summarized as the three "how"s: how much, how ready and for how long can groundwater be delivered from watersheds? A complementary goal was to identify and quantify the role of watershed characteristics controlling these "how"s. The methodology combined hydrologic modeling and GIS and the results for the test site (Paraopeba River basin, Brazil) were: (1) the studied river tributaries mostly drain regolith aquifers with short hydrologic turnover times (1.3-23.7 yr) and small aquifer mobile storages (0.1-1.3 m), but high specific yields (0.2-8.2 m/yr), being generally prone to hydrologic droughts; (2) the specific discharge is primarily elevation controlled (via precipitation increases with altitude), but relates positively with drainage density as well; (3) the mobile storage in the Quadrilátero-Ferrífero mountain is larger than elsewhere, being influenced by a local geomorphologic setting (higher coverage with concave hillslopes); (4) the groundwater contribution to streamflow discharge is high (> 50 %, on average), being improved with the coverage of argisols; (5) vulnerability to droughts could be alleviated through expansion of water-retention infrastructure in specific regions, as well as through land use conversions targeting reduced evapotranspiration or sustainable land management of argisol and concave surface landscapes. Although applied to a specific catchment, our results stand on a site-independent methodological framework. Thus, the understanding about groundwater security gained with this study can be inspiring to other workers dealing with tropical climate landscapes.
... This makes it possible to measure changes in moisture and water content from the surface down to a depth of several hundred metres (Martínez-Moreno et al., 2015). This technique is used, for example, in agriculture, in determining the groundwater level, in aquifers and in structural geology, among others (Martínez-Martos et al., 2017;Martos-Rosillo et al., 2019). ...
Article
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Dry periods in semi-arid regions constitute one of the greatest hazardous features that agriculture faces. This study investigates the effects of using a new device called ‘Hydroinfiltrator Rainwater Harvesting System (HRHS) on the water balance of soils. It was designed for arid and semi-arid zones affected by long periods of drought punctuated by heavy rainstorms. The new hydroinfiltrator consists of a net-like shell filled mainly with biochar. It is cylindrical in shape, is placed vertically and is half-buried in the soil around the crop tree to facilitate the infiltration of rainwater, irrigation or runoff water deep into the soil. The experimental plot is located in Baena (Córdoba, southern Spain) in an olive grove where the hydroinfiltrator was installed in 90 olive trees while 10 were left as a control group. In the xeric climate (bordering on arid), typical of the region, soils without a hydroinfiltrator have had a low infiltration rate, which reduces the effectiveness of precipitation and significantly increases the risk of water erosion. The effects of infiltration assisted by the device were analysed by simulating a torrential rain in which 600 L of water were passed through the hydroinfiltrator on an olive tree which had been installed 3 years previously. Geophysical methods (electrical resistivity tomography, ERT), direct analyses of soil samples, both in situ and in the laboratory, and theoretical flow models indicated a very significant increase in soil moisture (which nearly tripled in respect to the control group) because water was absorbed into the soil quickly, preventing runoff and water erosion. The soil moisture at 20 cm depth was 2.97 times higher with the HRHS than in the control plots. In addition, olive production increased by 211% and was higher in fat yield by 177%. Moreover, the resistivity profiles, taken by ERT showed that the water that entered the soil accumulated in the root zone of the olive tree, encouraged by the preferential pathways created by the roots and away from the surface, which prevented rapid evaporation during the high temperatures of spring and summer. Here we show for the first time that the use of the hydroinfiltrator rainwater harvesting system represents a significant improvement in the use of scarce water resources caused by climate change, providing agronomic and environmental benefits for rainfed, Mediterranean agricultural systems.
... Table 5 also illustrates that the slope is the second most determinant factor in assessing the MAR suitability potential, with a global weight of 13.33%. Here, the existing literature further recognizes the critical role played by the slope factor such that not only hydro-morphological variabilities (such as infiltration rates, surface water flow, sedimentation, etc.) [87,88] but also the feasibility of the MAR techniques (engineering considerations, compatibility with land use, etc.) [89] are ascertained based on the topographical conditions. For instance, Fathi et al. [90] highlighted that steep slopes generally result in faster runoff, which limits the amount of water available for recharge, and gentle slopes, on the other hand, promote the penetration of water, allowing for higher recharge rates and the improved effectiveness of MAR techniques. ...
Article
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Given the prevailing arid climate and rapid population growth, groundwater resources face unprecedented challenges globally, including depletion, seawater intrusion, and contamination. Managed aquifer recharge (MAR) technologies have emerged as valuable solutions to address these pressing issues. However, identifying suitable regions for MAR activities is a complex task, particularly at the country level. Therefore, in this study, we propose a robust approach that combines the fuzzy analytical hierarchy process (AHP) and the technique for order of preference by similarity to ideal solution (TOPSIS) to delineate suitable sites for MAR structures. The proposed model was applied to Djibouti, a hot, dry, and water-stressed country. We identified a set of nine decision criteria and conducted a pairwise comparison survey to determine their relative importance. Additionally, the TOPSIS method was employed to integrate the decision layers and prioritize the study area. The results highlight the significance of rainfall, the slope, and the NDVI as the most influential decision parameters, while the drainage density has the least impact. A suitability analysis reveals that 16.38%, 17.96%, and 30.41% of the country have a very high, high, and moderate potential for MAR activities, respectively. Furthermore, a sensitivity analysis demonstrates the stability of the proposed model, affirming the usefulness of the generated suitability map.
... In this context, geophysics has emerged as a non-destructive method to survey the subsurface at various scales and depths and in some occasions hydrogeological processes (Binley et al., 2015;Robinson et al., 2008). Electrical Resistivity Tomography (ERT) has been widely used (Samouelian et al., 2005) for soil moisture studies (Araya Vargas et al., 2021), the identification of groundwater aquifer geometry, and the study of geological structures (Ball et al., 2010;Martos-Rosillo et al., 2019;Robert et al., 2011). ERT cross-sections can be aligned to reveal resistivity contrasts resulting from geological structures and to construct a 3D representation based on previous geological knowledge . ...
... Moreover, the Sierra Nevada is plenty of uncoated ditches excavated in the ground (locally known as 'acequias de careo'), originally from the Middle Ages (Martín-Civantos 2010) with an important cultural and hydrological value. This irrigation system was designed to infiltrate the snow melt and runoff water in the wetter months to have spring water supply during the driest months (Martos-Rosillo et al. 2019). Nowadays, more than 700 km of acequias is still working in the Sierra Nevada as a sustainable groundwater recharge system. ...
Article
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An updated and complete landslide inventory is the starting point for an appropriate hazard assessment. This paper presents an improvement for landslide mapping by integrating data from two well-consolidated techniques: Differential Synthetic Aperture Radar (DInSAR) and Landscape Analysis through the normalised channel steepness index ( k sn ). The southwestern sector of the Sierra Nevada mountain range (Southern Spain) was selected as the case study. We first propose the double normalised steepness ( k snn ) index, derived from the k sn index, to remove the active tectonics signal. The obtained k snn anomalies (or knickzones) along rivers and the unstable ground areas from the DInSAR analysis rapidly highlighted the slopes of interest. Thus, we provided a new inventory of 28 landslides that implies an increase in the area affected by landslides compared with the previous mapping: 33.5% in the present study vs. 14.5% in the Spanish Land Movements Database. The two main typologies of identified landslides are Deep-Seated Gravitational Slope Deformations (DGSDs) and rockslides, with the prevalence of large DGSDs in Sierra Nevada being first revealed in this work. We also demonstrate that the combination of DInSAR and Landscape Analysis could overcome the limitations of each method for landslide detection. They also supported us in dealing with difficulties in recognising this type of landslides due to their poorly defined boundaries, a homogeneous lithology and the imprint of glacial and periglacial processes. Finally, a preliminary hazard perspective of these landslides was outlined.
... MAR mostly utilizes surface water (e.g., river, lake) as the source, and can be grouped into four categories: enhanced infiltration, induced bank infiltration, well injection and enhanced storage. The procedure is currently designed for many regions and practiced in many others (Itani et al., 2022;Liu et al., 2022;Martinsen et al., 2022;Pavelic et al., 2022), and has been used for a long time based on nature-based solutions (Jódar et al., 2022a(Jódar et al., , 2022bMartos-Rosillo et al., 2019;Ochoa-Tocachi et al., 2019;Oyonarte et al., 2022). In spite of being an effective strategy to restore groundwater in numerous overdraft regions, the MAR needs monitoring to evaluate the potential change in groundwater quality during the process Hübner et al., 2022;Xia et al., 2022;Zheng et al., 2023), especially if reclaimed water is used . ...
Article
Water security is an expression of resilience. In the recent past, scientists and public organizations have built considerable work around this concept launched in 2013 by the United Nations as "the capacity of a population to safeguard sustainable access to adequate quantities of acceptable quality water for sustaining livelihoods, human well-being, and socio-economic development, for ensuring protection against water-borne pollution and water-related disasters, and for preserving ecosystems in a climate of peace and political stability". In the 27th Conference of the Parties (COP27), held in Sharm El-Sheikh (Egypt) in last November, water security was considered a priority in the climate agenda, especially in the adaption and loss and damage axes. This discussion paper represents the authors' opinion about how the conference coped with water security and what challenges remain to attend. As discussion paper, it had the purpose to stimulate further discussion in a broader scientific forum.
... Una vez finalizada la época de lluvias y el deshielo, el río Trevélez aún mantiene su caudal durante julio, agosto y septiembre, caudal que se explica por la función de las acequias de careo y otras acequias de tierra provocando el paso del agua por los acuíferos superficiales que a lo largo del verano van desaguando en manantiales, arroyos y al propio río (Barberá et al., 2018;Martos-Rosillo et al., 2019b). Esto permite que aguas abajo de las acequias el caudal del río, barrancos y manantiales se mantenga lo suficiente para permitir la existencia de otros regadíos y vegetación de ribera. ...
Chapter
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Water management in tue Alpujarras has medieval origins. In the Trevélez river watershed, traditional management responds to the concept of integrated water resources management. In the upper the watershed, a significant part of the spring runoff flow, coming from the melting of the snow, is diverted from ravines to “careo” ditches, whose function is to recharge shallow aquifers. Thus, the water is stored temporarily, regulating the flow of the river, so that in summer it has enough water to divert it to irrigation ditches in the middle and lower watershed. This is the Water Sowing and Harvesting that this chapter describes. On the one hand, flow measurements at the head of the water diverted to “careo” ditches is presented, quantifying its regulating effect on the river. On the other hand, a water balance of the Busquístar ditch, one of the main irrigation ditches in the Trevélez river basin, is made. In this water balance, the flows that result in agricultural production and others that provide ecosystem services are considered. The latter create biodiversity and landscape, supplying with seepage water to riparian forests along the ditch and contributing to the regulation of the lower course of the Trevélez River. These are, therefore, several integrated Nature-Based Solutions, which led to a review of the concept of irrigation efficiency, considering, first, the scale effect, and, second, the benefit of the various ecosystem services.
... Human settlements in Sierra Nevada are documented since the Neolithic (Sánchez-Hita 2007), generating intense landscape modifications since the seventh century (Muslim period) through the construction of acequias, i.e., waterditches for the management of meltwater favoring the infiltration and recharge of aquifers and increasing soil protection against erosion produced by runoff water (Jódar et al. 2018;Martos-Rosillo et al. 2019). In the middle of the twentieth century, agricultural industrialization and the rural exodus led to the abandonment of agricultural activities, a situation that, together with the reforestation with pine trees and the declaration of protected area, led to big changes in the territory (Zamora et al. 2016). ...
Article
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Unlabelled: While we know that climate change is having different impacts on various ecosystems and regions of the world, we know less how the perception of such impacts varies within a population. In this study, we examine patterns of individual variation in climate change impacts reports using data from a sample (n = 238) drawn from 33 mountainous municipalities of Sierra Nevada, Spain. Sierra Nevada inhabitants report multiple climate change impacts, being the most frequently reported changes in snowfall and snow cover, abundance of terrestrial fauna, freshwater availability, and extreme temperatures. Reports of climate change impacts vary according to informants' sociodemographic characteristics and geographical location. People with life-long bonds with the environment and higher connection and dependence upon ecosystem services report more climate change impacts than other informants, as do people with lower level of schooling. We also found that reports of climate change impacts vary according to geographic areas, which reinforces the idea that climate change generates differentiated impacts even at small geographical scales. Understanding intracultural variation in reports of climate change impacts not only gives an enriched picture of the human dimensions of climate change but might also help design more targeted mitigation and adaptation responses. Supplementary information: The online version contains supplementary material available at 10.1007/s10113-022-01981-5.
... As a result, surface direct runoff is low when compared to other basins with similar pluviometry, being the slower subsurface and base flows significant components of the fluvial regime, that lacks a direct connection river-aquifer in this area. This delay is enhanced in the southern face also due to the existence of "acequias de careo", ancient traditional recharge systems dating from the Arab time that still derive snowmelt towards infiltration areas that downstream spring and feed agricultural areas downhill in the valleys (Barberá et al. 2018;Martos-Rosillo et al. 2019; Chapter 1.3). Moreover, this structure also explains the large amount of springs found in Sierra Nevada (Castillo 2002) which, together with the mountain remaining glacier lagoons (Castillo 2016), constitute indirect sensors of the hydroclimatic seasonal regime every year, as they partially/totally dry or replenish, or get frozen or melt in the case of the lagoons, highly-valued ecosystems directly affected by the climate shifts (González-Olalla et al. 2018). ...
Chapter
Sierra NevadaSierra Nevada is the southernmost snowSnow area in Europe and its singular geographical location, together with its high altitudes, result in strong gradients of the local climateClimate and hydrology, and rich biodiversityBiodiversity. This chapter aims at providing insights into the major components of the energy and water balance in snowpacks in Mediterranean areas and across the different snowSnow domains found in Sierra NevadaSierra Nevada. For this, key descriptors of the snowSnow regime are included from both historical observations and physical modelling during the 1961–2015 period, in the framework of different research projects for the last two decades. The observed relevance of water fluxes to the atmosphere as evaposublimation under these conditions, up to 30–35% of the annual water stored as snowSnow, may be enhanced by the generally observed shift towards torrentiality in the precipitationPrecipitation and snowfall regimes in this site. However, the impacts on hydrology are highly non-linear, with in-season timing of snowSnow events, and their duration, being determinant for the hydrological response and the associated pulse-events of sediment production and deposition downstream. The results highlight the singularity of Sierra NevadaSierra Nevada in the context of the high mountain areas in Mediterranean-type regions, and the complexity of the snowSnow dynamics in these areas in the current global warming scenario.
... Past glacial activity has contributed to the unconsolidated deposits in the region due to the weathering of rocks. A previous study also established a pattern between the weathering of rocks towards the increased groundwater recharge potential [121]. An increased recharge was also observed in the area of higher unconsolidated deposits in another study [120]. ...
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Owing to the extensive global dependency on groundwater and associated increasing water demand, the global groundwater level is declining rapidly. In the case of Islamabad, Pakistan, the groundwater level has lowered five times over the past five years due to extensive pumping by various departments and residents to meet the local water requirements. To address this, water reservoirs and sources need to be delineated, and potential recharge zones are highlighted to assess the recharge potential. Therefore, the current study utilizes an integrated approach based on remote sensing (RS) and GIS using the influence factor (IF) technique to delineate potential groundwater recharge zones in Islamabad, Pakistan. Soil map of Pakistan, Landsat 8TM satellite data, digital elevation model (ASTER DEM), and local geological map were used in the study for the preparation of thematic maps of 15 key contributing factors considered in this study. To generate a combined groundwater recharge map, rate and weightage values were assigned to each factor representing their mutual influence and recharge capabilities. To analyze the final combined recharge map, five different assessment analogies were used in the study: poor, low, medium, high, and best. The final recharge potential map for Islamabad classifies 15% (136.8 km 2) of the region as the "best" zone for extracting groundwater. Furthermore, high, medium, low, and poor ranks were assigned to 21%, 24%, 27%, and 13% of the region with respective areas of 191.52 km 2 , 218.88 km 2 , 246.24 km 2 , and 118.56 km 2. Overall, this research outlines the best to least favorable zones in Islamabad regarding groundwater recharge potentials. This can help the authorities devise mitigation strategies and preserve the natural terrain in the regions with the best groundwater recharge potential. This is aligned with the aims of the interior ministry of Pakistan for constructing small reservoirs and ponds in the existing natural streams and installing recharging wells to maintain the groundwater level in cities. Other countries can expand upon and adapt this study to delineate local groundwater recharge potentials.
... In 2016, it was introduced as a guideline "Supporting the implementation of green infrastructure" by the European Commission (EU Commission, 2019). The BGINs use natural, semi-natural, and artificial green spaces, providing ecosystem services from supply to support, including air purification, climate regulation, carbon storage, reduce the risk of extreme events, biodiversity conservation, integrated water resources management and aesthetic and cultural services Huang et al., 2018;Opperman et al., 2010;Valente et al., 2020;Van Oijstaeijen et al., 2020;Yao et al., 2017;Zhang et al., 2015;Zhang and Muñoz Ramírez, 2019;Martos-Rosillo et al., 2019). In addition, they offer an ecological integrity function and a holistic perspective to build resilience and address complex urban challenges, in which several problems need to be handled concurrently, with limited resources and space constraints (Alves et al., 2016;Frantzeskaki et al., 2019). ...
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The Paiva River is considered one of the least polluted rivers in Europe and its watershed has a high conservation value. However, the Paiva River basin suffers pressures related with recurrent disturbances in land use, such as forest fires, agricultural activities, urbanization and pressures that affect the natural hydromorphological conditions and the continuity of watercourses. Blue and Green Infrastructures (BGINs) emerge to improve biodiversity, sustainability and the supply of ecosystem services while improving socioeconomic aspects. Thus, this article aims to identify priority areas in the basin, for intervention with these infrastructures. For that, a spatial multicriteria decision analysis (MDCA) was carried out according to several data related to the Paiva River Basin. As local politicians and responsible entities for the natural resources management are the main experts on the problems and their possible solutions at the local level, they were involved in this decision-making model. Therefore, these specialized stakeholders did the weighting assignment according to the most or least importance of the same for the work. The map of priority locations to implement BGINs was obtained in the sequel. To the top 5 priority areas, stakeholders attributed the best solutions based on nature. The most recommended BGINs were recovery/maintenance of riparian vegetation and conservation and reforestation of the native forest, both presented in four of the five areas, and introduction of fuel management strips presented in three of the five areas. Thus, we concluded that it is extremely important to include the communities and the competent entities of nature and environment management in scientific projects related to conservation, forming a synergy that makes it possible to combine scientific knowledge with local experience acquired in the field. This project uses a very flexible methodology of local data and can be a great example to be implemented in other hydrographic basins anywhere in the world.
... Sin embargo, estas zonas generalmente ya disponen de infraestructuras de regulación y almacenamiento, así como de una cultura de gestión de la escasez. Precisamente, su ubicación geográfica expuesta a la escasez de agua se refleja en una larga tradición y cultura de adaptación en materia de gestión de los recursos hídricos que se concreta en ejemplos como los sembradores de lluvia y acequias de careo que datan de hace casi diez siglos en Sierra Nevada (Martos et al., 2018;Martos-Rosillo et al., 2019). Los recursos hídricos en España proceden en su mayoría de las precipitaciones que alimentan las En el presente capítulo, el análisis se ha centrado en los diferentes componentes del ciclo hidrológico. ...
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En este informe promovido por el Ministerio para la Transición Ecológica y el Reto Demográfico (MITECO), con la coordinación técnica del Basque Centre for Climate Change (BC3), se exponen los principales impactos del cambio climático en los distintos sectores productivos y sistemas naturales de España, se elabora una relación de los principales riesgos derivados de estos impactos, así como una propuesta de valoración sobre el grado de urgencia para ser abordados. Para ello, se analiza documentación publicada en un total de 10 ámbitos de trabajo o sectores y sistemas naturales considerados prioritarios tanto en el PNACC-1 como en el PNACC-2 (recursos hídricos, ecosistemas terrestres, agricultura y ganadería, medio marino, costas, áreas urbanas, salud, energía, transporte y turismo), se sintetiza la información sobre impactos del cambio climático para cada ámbito de trabajo y se profundiza en la interrelación de los riesgos entre diferentes ámbitos; de manera que pueda servir para informar a las personas y organizaciones interesadas en conocer los riesgos derivados del cambio climático en España. Entre los principales resultados destacan la reducción de las precipitaciones en la última década de este siglo, el aumento de fenómenos extremos, el aumento de temperaturas máximas y mínimas, y olas de calor más prolongadas. En el medio marino se prevé el aumento en 2ºC de la tª superficial del agua, la subida del nivel del mar y cambios en la salinidad y en el oleaje.
... Among different types of groundwater management strategies, managed aquifer recharge (MAR) is popular because of its low implementation cost, low evaporation loss compared to surface reservoir, and ability to infiltrate large volume of water from different sources, including river or stream waters, urban and agricultural runoff, and treated municipal wastewater (Dillon, 2009;Dillon et al., 2019). Artificially recharging groundwater has been practiced using ancient methods such as sowing and harvesting (also known as "careos", "amunas") started several centuries ago in Europe and South America (Martos-Rosillo et al., 2019). MAR methods are designed to intentionally infiltrate water from different sources into an aquifer and extract the treated water for later use (Fig. 1). ...
Article
Increasing water demand for applications in urbanized areas, agriculture sectors, and energy extraction, and dwindling surface water due to changing climate accelerate the depletion of groundwater. Managed aquifer recharge (MAR) is one of the several methods that can help achieve long-term water sustainability by increasing the natural recharge of groundwater reservoirs with water from non-traditional supplies such as excess surface water, stormwater, and treated wastewater. Despite the multiple benefits of MAR, the wide-scale implementation of MAR is lacking, partly because of the challenge to select the location for MAR implementation and identify the MAR type based on site conditions and needs. In this review, we provide an overview of MAR types with a basic framework to select and implement specific MAR at a site based on water availability and quality, land use, source type, soil, and aquifer properties. Our analysis of 1127 MAR projects shows that MAR has been predominantly implemented in sites with sandy clay loam soil (soil group C) and with access to river water for recharge. Spatial analysis reveals that many regions with depleting water storage have opportunities to implement MAR projects. Analyzing data from 34 studies where stormwater was used for recharge, we show that MAR can remove dissolved organic carbon, most metals, E. coli but not efficient at removing most trace organics, and enterococci. Removal efficiency depends on the type of MAR. In the end, we highlight potential challenges for implementing MAR at a site and additional benefits such as minimizing land subsidence, flood risk, augmenting low dry-season flow, and minimizing salt-water intrusion. These results could help identify locations in the water-stressed regions to implement specific MAR for water sustainability.
... In the 1950ś, the way to irrigate the crops by flooding systems, allowed to recharge the aquifers. The oldest system of irrigation channels in Europe (Martos-Rosillo et al., 2019) had, in this way, the function of watering the crops and recharging the aquifers. ...
Article
The supply of ecosystem services is largely determined by changes in land use and cover. Here, we analysed how the supply and interactions among four ecosystem services have evolved over five decades in a mountain biosphere reserve largely dominated by human land uses. We modelled pastures for livestock, crop production, aquifer recharge and erosion prevention based on land use maps along five years. Multi-scale analyses were conducted to show the temporal evolution of the spatial patterns and interactions among those ecosystem services at three nested spatial scales (biosphere reserve, watershed and cell level). The overall increase in the supply of pastures and erosion prevention and the decline of crops and aquifer recharge were closely related to the abandonment of traditional land uses, particularly during the first decades. At finer scales, our results revealed that the cell areas with significant interactions among services (i.e. trade-offs and synergies) decreased from 1956 to 2007. Such evolution of trade-offs and synergies seemed to be driven by management decisions on land-use changes. Finally, we discussed the implications of our results in the context of ecosystem services’ optimization through management actions on land uses in mountain areas.
... En la Alpujarra esquistosa existe desde la presencia árabe-beréber (siglo VIII) un sistema de trasporte y almacenamiento subterráneo de las aguas de escorrentía superficial que se conoce con el nombre de acequias de careo (Pulido-Bosch y Sbih, 1995;Martos-Rosillo et al., 2019.). La misión primigenia de estas acequias era la de transportar el agua hasta los campos de cultivo que se extendían a lo largo de las laderas de Sierra Nevada. ...
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This study identifies protected natural areas that are related to groundwater in Spain. The methodology used has been applied to the natural areas covered within the scope of the three legal frameworks established in Law 42/2007, 13 December 2007 on Natural Heritage and Biodiversity. These are as follows: (a) areas protected by the Spanish State or its Autonomous Communities; (b) areas protected by the Natura 2000 Network and (c) areas protected by international instruments. Within the first typology the Natural Parks, Natural Reserves, Natural Monuments and Protected Landscapes are analyzed. The second includes the protected areas of the Natura 2000 Network and the third the Wetlands of International Importance of the Ramsar Convention; natural sites of the World Heritage List; Convention for the Protection of the Marine Environment of the north-east Atlantic (OSPAR); Specially Protected Areas of Mediterranean Importance (SPAMI); GEOparks declared by UNESCO; Biosphere Reserves declared by UNESCO and European Network of Biogenetic Reserve. Finally, a hydrogeological characterization of each of the 15 National Parks in Spain is carried out.The aim of the paper is to identify and propose a first catalogue of protected natural areas that have a relationship with groundwater either from recharging the aquifer or drainage through rivers, springs or wetlands.
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The significance of Integrated Watershed Management (IWM) has increased in recent years due to its ecological, economic, and social implications. To align with these principles and achieve efficiency, watershed management necessitates the evaluation and integration of numerous diverse factors. This literature review aims to examine the current research trend in IWM and its association with various thematic elements. The identified thematic elements include water resources management, decision-making processes, agricultural and forested watersheds, soil management, natural hazards, stakeholder involvement, climate change, policy frameworks, cost management and risk analysis, livelihoods, ecosystem services, habitat and biodiversity conservation, and tourism. The predominant thematic elements were water resource management, decision-making, and agricultural and forested watersheds. The countries that were most frequently referred to in the examined literature were Ethiopia, China, the USA, and Iran. A synthesis of data obtained via the analysis of scientific research trends in the specified domain can serve as a basis for the establishment and strategizing of comprehensive watershed management. While it is important to consider all these aspects combined in IWM practice, it is also essential to have a comprehensive grasp of each factor as a vital step in integrating them. The participants involved in this endeavour, hailing from diverse professional backgrounds, must engage in close collaboration to successfully integrate the aforementioned aspects. The collaborative method can only have a chance of success if all participants involved demonstrate a high level of dedication. The level of dedication required should be grounded in a comprehensive understanding of the difficulties and demands that are mutually shared by all involved parties.
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The impacts of both climate change and socioeconomic processes are driving the degradation of mountains and the ecological services they provide worldwide. In the tropical Andes, compounding glacier retreat, altered hydrological and precipitation regimes (eg off-season alternation of extreme dry and wet periods), and expansion of mining and other land uses are modifying hydrological services. Although initiatives to restore ecosystems and their services are increasing, conceptual models emerging from experiences on the ground are scarce. Based upon the experience of Peru's National Institute for Research on Glaciers and Mountain Ecosystems (INAIGEM) in the Piuray Ccorimarca microbasin (Cusco) in combining participatory action research and experiments at the plot scale, this article elaborates a conceptual model for the rehabilitation of hydrological services on the social–ecological systems of puna grassland. The model proposes multiscale (plot–pilot–microbasin) rehabilitation. At each level, the actions proposed include designing plots, selecting sites, implementing restoration activities, and evaluating and monitoring the sites. Our inductive model from the ground and plot can inform rehabilitation of hydrological services on puna grasslands elsewhere.
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The wave of modernization and globalization in the last century has rapidly involved a technological paradigm shift from indigenous irrigation water systems to modern systems in arid regions. Despite interest in the drought resilience of indigenous water systems, the impact of this paradigm shift on drought resilience remains poorly understood because previous studies have focused on fixed irrigation water systems. To fill this gap, we investigated the drought resilience of an indigenous and modern irrigation water system that coexists in the drought-prone Mahaweli H region of the Sri Lankan dry zone. To explain drought resilience, we quantified the historical irrigation system performance (1985-2021) of both water systems using the water duty indicator (i.e., the volume of water required to cultivate a unit land area). The statistical Pettitt test was used to detect significant change points in the time series of water duty, and we divided the time line into few periods based on the change points. Furthermore, a quantitative trend analysis of several socio-hydrological variables and a qualitative analysis of their socio-hydrological backgrounds with triggers of water duty were conducted to explain drought resilience path dependency in modern and indigenous water systems. The results indicated a higher drought resilience is embedded in the indigenous system as the mean water duty increment in drought years compared to non-drought years is 16.4% for the indigenous system and 58.3% for the modern system. In addition, drought resilience pathways that elucidated by water duty change points also demonstrated that indigenous water system features a higher drought resilience compared to the modern water system. The findings of this comparative study can contribute to the design of drought resilience improvement strategies in arid region irrigation water systems in a more comprehensive manner.
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The Muslim expansion in the Mediterranean basin was one the most relevant and rapid cultural changes in human history. This expansion reached the Iberian Peninsula with the replacement of the Visigothic Kingdom by the Muslim Umayyad Caliphate and the Muslim Emirate of Córdoba during the 8th century CE. In this study we made a compilation of western Mediterranean pollen records to gain insight about past climate conditions when this expansion took place. The pollen stack results, together with other paleohydrological records, archaeological data and historical sources, indicate that the statistically significant strongest droughts between the mid-5th and mid-10th centuries CE (450–950 CE) occurred at 545–570, 695–725, 755–770 and 900–935 CE, which could have contributed to the instability of the Visigothic and Muslim reigns in the Iberian Peninsula. Our study supports the great sensitivity of the agriculture-based economy and socio-political unrest of Early Medieval kingdoms to climatic variations.
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The Careo ditches, hydraulic elements of an ancestral water management system, play an essential role in the hydrological functioning of watersheds in Sierra Nevada (South of Spain). This study seeks to characterize the hydrochemical and stable isotope compositions of surface water and groundwater in the high mountain watershed of the Alhorí river. For this purpose, 46 samples from springs and surface streams were collected in June 2020 and their content in major ions, hydrogen and oxygen isotopes was analysed. The results show that altitude is clearly influencing the characteristics of the sampled waters. Furthermore, artificial groundwater recharge with careo ditches favours evapoconcentration. Overall, this research proves the existence of short-distance flows in the groundwater of the Alhorí river basin. Las acequias de careo, elementos hidráulicos de un sistema ancestral de gestión del agua, juegan un papel esencial en el funcionamiento hidrológico de las cuencas de Sierra Nevada (sur de España). En este estudio se lleva a cabo una caracterización hidroquímica e isotópica de las aguas, tanto superficiales como subterráneas, de la cuenca de alta montaña del río Alhorí. El estudio se ha realizado con datos procedentes de 46 muestras tomadas en junio de 2020. Tras el análisis de datos se evidencia un marcado patrón altitudinal que rige las características hidrogeoquímicas e isotópicas del agua. Además, procesos como la evapoconcentración, provocados por las acequias de careo, quedan claramente identificados. Por último, queda demostrada a partir de esta investigación la existencia de flujos de corto recorrido en las aguas subterráneas de la cuenca del río Alhorí.
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Water Sowing and Harvesting is part of the methods based on nature that take up ancestral practices for efficient use of water, favoring the recharge of aquifers in wet periods for use in dry periods. Properly estimating the water resources available in a region or basin is fundamental for the sowing of water, for which different hydrological models are used depending on the quantity and quality of the information. The case study is the Palomino River basin in the Sierra Nevada de Santa Marta (Colombia), a mountain watershed with little hydrological data available, as it typically happens in mountain areas. A hydrological model ensemble approach is proposed here to evaluate the water resources of the basin. The ensemble is composed of 12 conceptual lumped parameter models which are especially well suited for simulating the behavior of hydrological basins with scarce data. Manual calibration and validation are carried out for each model. Furthermore, a long-term simulation is performed to estimate available water resources while inferring the hydrological regulation indices of the watershed. The model ensemble approach allows coping with the uncertainty of hydrological balances in w with little data availability. The proposed methodology is simple and may be replicated in other mountain basins.
Technical Report
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Human cultural diversity is reflected in many different ways of knowing, being, and doing, each with specific histories, positionalities, and connections to ecosystems, landscapes, and the world. Such diversity results in plural knowledge systems. This white paper describes the characteristics and complexity of knowledge systems in the context of climate change. It notes the deficiencies of action to date on climate change, which has largely rested on scientific knowledge, and discusses the importance of drawing on other knowledge systems, particularly Indigenous knowledge and local knowledge. This paper synthesises evidence highlighting that Indigenous knowledge systems and local knowledge systems are dynamic, contemporary, and actively applied worldwide. Although Indigenous knowledge and local knowledge systems continue to be politically marginalised, the recognition of their role in climate governance is essential. We consider plural knowledge systems and the interactions and potential collaborations between them, with a goal of informing how they can most constructively, equitably, and inclusively be conceptualised and addressed when discussing and generating knowledge about and responses to climate change.
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CONTEXT: In the Middle Ages, the Muslims introduced communal water management in the Iberian Peninsula. Some irrigation systems of medieval origin are still in operation in the mountainous areas of Southern Spain. Snowmelt runoff is diverted during spring from high-altitude streams into contoured recharge ditches that convey the water to areas of high infiltration (shallow aquifers). This regulates and delays discharge into the main river, from which downstream flow is diverted, during late spring and summer, to irrigation ditches that supply terraces and fields on river plains. The Busquístar irrigation ditch and its irrigation scheme comprise one of these ancient systems. OBJECTIVES: 1) To characterize the Busquístar system, its water source and regulation, its water users' association, its multi-functionality, and its quality as a nature-based solution for water security. 2) To review the irrigation efficiency concept applied to the restoration of ancient irrigation systems, taking into account their ecosystem services. METHODS: i) Semi-structured interviews with stakeholders to evaluate irrigation system operation and perceptions of multi-functionality; ii) field surveys for description of the irrigation ditch and its riparian flora; iii) satellite imagery for quantifying riparian vegetation; iv) water balance for irrigation efficiency computation.
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Local ecological knowledge systems have been the basis of Sierra Nevada’sSierra Nevadasocial-ecological systemSocial-ecological system, which has co-evolved over more than ten centuries until nowadays, based on the knowledge, practices, and innovations deriving from the relationship between people and the ecosystems on which they depend. In Sierra NevadaSierra Nevada, this co-evolution is greatly influenced by the traditional water managementTraditional water management system, generating a “cultural landscapeCultural landscape.” However, during the twentieth-century Sierra NevadaSierra Nevada’s social-ecological systemSocial-ecological system was affected by diverse drivers of changeDrivers of change such as climateClimatechangeClimate change, rural exodus, land-use change, and conservationConservation government policies, which are threatening its stability and the transmission of the related local ecological knowledge. Local ecological knowledge on water management, traditional agricultural systems, and knowledge related to grazing and cattle raising should be included in the co-managementAdaptive co-management of the territory and representatives of this knowledge should be involved and collaborate with administration and researchers developing adaptive plants to reduce negative impacts of global changeGlobal change.
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Sierra NevadaSierra Nevada, comprising 2348 vascular floraFlora taxa (including 95 endemic taxa) is considered one of the most important plant hotspotsHot-spot within the Mediterranean region. Sierra NevadaSierra Nevada presents 362 taxa inhabiting the alpine area (ca. 242 km2), 75 endemic species (62 endemic plus 13 sub-endemic) among them, constituting ca. 79% of the endemismEndemism of the entire area. This high-mountain has preserved many species, allowing the current presence of many artic-alpine species, including twelve cold-adapted species with their southernmost limit here. There are 23 nano-hotspotsHot-spot, most of them occurring at the highest altitude, at the coldest parts. Altogether, they host 30% of the Baetic endemic floraFlora in just 0.07% of the area. Plant communities are also original, and they are composed of a mixture of Alpine and Mediterranean species. Climate changeClimate changeisClimate strongly impacting alpine biota leading to an adaptationAdaptation to the new conditions. When this adaptationAdaptation capacity is overcome species are forced to migrate to avoid extinction. Some responses are already noticeable in alpine areas, such as: phenological changes, altitudinal movements, increasing competitionCompetitionand hybridizationHybridization, and changes in plant assemblages. Direct impact related to human activities such as livestock grazing, use of fire to manage alpine pasturelands, mountain agriculture, outdoor activities, and infrastructure construction have additive effects toClimateclimate changeClimate change, and altogether they can exacerbate negative changes. Monitoring, evaluating, and understanding the effect of global changeGlobal change in the Mediterranean mountains is a top priority. We offer guidelines to orient the conservationConservation agenda at Sierra NevadaSierra Nevada: To (i) establish an early warning indicators system, (ii) preserve plant species and habitats, (iii) preserve threatened plant species ex situ, (iv) promote adaptive managementAdaptive management measures, (v) evaluate outdoor recreation activities, and (vi) control and regulate activities.
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Water sowing and harvesting (WS&H), a term adopted from Latin America, is an ancestral process that involves gathering and infiltration (sowing) of rainwater, surface runoff, and groundwater to recover it (harvesting) later and/or elsewhere. The WS&H systems follow the approaches of integrated water resource management, nature-based solutions and the recovery of ancestral knowledge for water management. In this paper, we present some representative types of WS&H in Latin America, Spain, and Portugal, and then, we focus on the Paltas Catacocha Ecohydrology Demonstration Site in southern Ecuador as a study case. The recovery of such local ecohydrological knowledge in the study case has made enabled the regulation and retention water in the aquifers through the restoration of artificial wetlands (cochas) and stream dams (tapes or tajamares). Also, this ancestral way of water management has recently supported and reactivated several biological aspects and human activities. The experience of the Paltas Catacocha site shows that there are more appropriate and sustainable alternatives to gray infrastructure projects for water resources management and denotes the need to investigate ancestral water and soil management systems.
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Maintaining sustainable development in semi-arid regions is a complex task due to scarce precipitation, with notable temporal and spatial variations that complicate planning and proper management of water resources. Most of the water extractions from the aquifers in southeast Spain are carried out to supply a growing agricultural sector and increasingly successful tourism, which is the case of the Sierra de Gador-Campo de Dalias system. Savings, reutilization and awareness among water users are essential elements in any sustainable water policy. Some of the possible solutions proposed that offer low environmental impacts include certain infrastructure works, such as dams, ditches or recharge in gravel pits. Also, desalinization plants constitute a technical alternative in theory but involve high costs. The integration of all these resources, together with their proper management, is necessary to ensure the future water supply and economic growth in the region, safeguarding the state of its aquifers that are currently intensely overexploited.
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Managed aquifer recharge (MAR) schemes often employ in-channel modifications to capture flow from ephemeral streams, and increase recharge to the underlying aquifer. This review collates data from 79 recharge dams across the world and presents a reanalysis of their properties and success factors, with the intent of assessing the potential of applying these techniques in Europe. This review also presents a narrative review of sand storage dams, and other in-channel modifications, such as natural flood management measures, which contribute to the retardation of the flow of flood water and enhance recharge. The review concludes that in-channel MAR solutions can increase water availability and improve groundwater quality to solve problems affecting aquifers in hydraulic connection with temporary streams in Europe, based on experiences in other parts of the world. Therefore, to meet the requirements of the Water Framework Directive (WFD), in-channel MAR can be considered as a measure to mitigate groundwater problems including saline intrusion, remediating groundwater deficits, or solving aquifer water quality issues.
Article
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Managed aquifer recharge (MAR) is becoming a common practice worldwide. MAR is carried out in different environments from coastlands to highlands, in megalopolis, farmlands and pristine areas, and in arid and humid regions. Pre‐Alpine aquifers represent an optimal target when MAR is aimed at storing large amounts of high‐quality waters. In fact, pre‐Alpine aquifers are generally characterized by high permeability and a thick unsaturated zone, with the catchments crossed by watercourses rich of high‐quality water. Here, we focus the attention to a representative pre‐Alpine aquifer system located in the Friuli region, northeastern Italy. A 1‐year long MAR test was carried out through a ~700 m² infiltration basin recharged by water diverted from a nearby channel. The site was characterized from the hydrogeological viewpoint, and the MAR test was monitored through time‐lapse hydrogeophysics, water level and piezometric records, and physicochemical water characterization. The data set was used to calibrate a local groundwater flow model, showing that MAR recharged the 50 m deep phreatic aquifer with 1,000 m³/day. Hydrogeologic data made available by previous studies were processed to develop a groundwater model of the regional aquifer that allowed for estimating the natural groundwater recharge of the phreatic system and, subsequently, evaluating the MAR effects in the context of the natural balance. If a single MAR site, like the tested one, plays a certain effect at a local scale only, the MAR implementation on several gravel pits and large‐diameter wells scattered in the region could store several million cubic meters of water per year, significantly raising the water table and improving the groundwater quality.
Chapter
Water Sowing and Harvesting (WS&H) consists of a series of ancestral procedures by which humans collect and infiltrate (sow) rainwater and runoff underground, so as to recover (harvest) it downgradient at some later time. This management of the water has made it possible for various regions of Ibero-America that is, Latin America plus the Iberian Peninsula to overcome dramatic cultural and climatic changes over the centuries. The principles governing WS&H coincide with those pursued under the present paradigm of Integrated Water Resource Management. Moreover, WS&H implies a better use of water and enhanced conservation of the environment and patrimony, as well as recognition of rural communities as vital custodians of the land and of its relevant cultural aspects. The main WS&H systems that serve Ibero-American countries are described here, emphasizing the principles underlying this means of water management as exemplary of hydrogeoethical systems.
Article
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Groundwater recharge indicates the existence of renewable groundwater resources and is therefore an important component in sustainability studies. However, recharge is also one of the least understood, largely because it varies in space and time and is difficult to measure directly. For most studies, only a relatively small number of measurements is available, which hampers a comprehensive understanding of processes driving recharge and the validation of hydrogeological model formulations for small- and large-scale applications. We present a new global recharge dataset encompassing N5000 locations. In order to gain insights into recharge processes,we provide a systematic analysis between the dataset and other global-scale datasets, such as climatic or soil-related parameters. Precipitation rates and seasonality in temperature and precipitation were identified as the most important variables in predicting recharge. The high dependency of recharge on climate indicates its sensitivity to climate change.We also show that vegetation and soil structure have an explanatory power for recharge. Since these conditions can be highly variable, recharge estimates based only on climatic parameters may be misleading. The freely available dataset offers diverse possibilities to study recharge processes from a variety of perspectives. By noting the existing gaps in understanding,we hope to encourage the community to initiate new research into recharge processes and subsequently make recharge data available to improve recharge predictions.
Article
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En la cara norte de Sierra Nevada (Granada) existen sistemas de riego desde época medieval que, gracias a una gestión racional del agua del deshielo, han logrado sobrevivir hasta la actualidad. Las comunidades de regantes son las instituciones responsables del funcionamiento y conservación de estos sistemas de riego y su labor cotidiana descansa en dos pilares fundamentales: por una parte, la organización comunitaria para el aprovechamiento de un recurso escaso y, por otra, la posesión de conocimientos etnoecológicos vitales para comprender el medio natural serrano. Ambos aspectos constituyen un rico Patrimonio Inmaterial que debe ser reconocido y protegido, pues de él depende la conservación del paisaje cultural en su conjunto.
Article
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Water resources worldwide are under severe stress from increasing climate variability and human pressures. In the tropical Andes, pre-Inca cultures developed nature-based water harvesting technologies to manage drought risks under natural climatic extremes. While these technologies have gained renewed attention as a potential strategy to increase water security, limited scientific evidence exists about their potential hydrological contributions at catchment scale. Here, we evaluate a 1,400-year-old indigenous infiltration enhancement system that diverts water from headwater streams onto mountain slopes during the wet season to enhance the yield and longevity of downslope natural springs. Infiltrated water is retained for an average of 45 d before resurfacing, confirming the system’s ability to contribute to dry-season flows. We estimate that upscaling the system to the source-water areas of the city of Lima can potentially delay 99 × 106 m3 yr−1 of streamflow and increase dry-season flows by 7.5% on average, which may provide a critical complement to conventional engineering solutions for water security.
Thesis
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In this PhD thesis we exposed the evolution of different fundamental aspects, from the concept of heritage to the development of Archaeology and Museology, through communication and participation strategies and finally the normative framework, in term of cultural and environmental facets. All this has served to frame the case study of the MEMOLA project in relation to the archaeological analysis of cultural landscapes and in regards to the participation of local communities and general public. This study has focuses on the study areas of Cáñar, Lugros and Lanteira, rural villages located in the south and north faces of Sierra Nevada. The work with local stakeholders has been arranged from two different perspectives. The first, and most important, has been the recovery of historical irrigation systems. The second, that came next, focused around an archaeological site. From these approaches we have generated a wide range of different activities and resources of communication and participation. The goal was to replicate the methodology in different municipalities, with the local communities involved in the recovery of an asset, such as irrigation ditches, to diagnose possible repeating patterns. From this perspective, we applied, as far as possible, this methodological approach to an archaeological site as well. We have had three years of field work that allowed us to compare different effects and relationships between community-heritage-territory, academy-institutions, academy-community, academia-administration-community or administration-community-territory. These accomplishments in the territory generated a wide range of activities that transcend the boundaries of the study areas, thus including adjacent municipalities and ranging from dissemination, education, socialization to public involvement and engagement with the MEMOLA project.
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Resumen En las partes altas de Sierra Nevada (sur de España) se realiza, desde época andalusí (Edad Media), un Sistema Integrado de Gestión del Agua Subterránea, en el que las acequias de careo constituyen un elemento clave. Estos canales excavados en el terreno están diseñados para recargar las aguas procedentes del deshielo, a lo largo de su recorrido y en distintas zonas concretas, donde hay una mayor permeabilidad del terreno. Una vez que el agua se infiltra en las partes altas de los valles,
Article
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Different types of managed aquifer recharge (MAR) schemes are widely distributed and applied on various scales and for various purposes in the European countries, but a systematic categorization and compilation of data has been missing up to now. The European MAR catalogue presented herein contains various key parameters collected from the available literature. The catalogue includes 224 currently active MAR sites found in 23 European countries. Large quantities of drinking water are produced by MAR sites in Hungary, Slovakia, the Netherlands, Germany, Finland, Poland, Switzerland and France. This inventory highlights that, for over a century, MAR has played an important role in the development of European water supply and contributes to drinking-water production substantially. This development has occurred autonomously, with “trial-and-error” within the full range of climatically and hydrogeologically diverse conditions of the European countries. For the future, MAR has the potential to facilitate optimal (re)use and storage of available water resources and to take advantage of the natural purification and low energy requirements during MAR operations. Particularly with respect to the re-use of wastewater treatment-plant effluent and stormwater, which is currently underdeveloped, the use of MAR can support the public acceptance of such water-resource efficient schemes. Particularly for the highly productive and urbanized coastal zones, where the pressure on freshwater supplies increases by growing water demand, salinization and increased agricultural needs for food production (such as along the Mediterranean and North Sea coasts), MAR is expected to be increasingly relied on in Europe.
Conference Paper
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For a groundwater supply to be sustainable, its rate of recharging needs to match the demand. If natural replenishing rate falls short of the demand, water users have to take steps to enhance it. That requires a good understanding of the groundwater flow mechanism in the locality, a quite difficult task even for today's water experts. Evidence shows that our ancestors used their observational skills and trial and error techniques to overcome this difficulty. When the leaders had to mobilize the villagers for construction and maintenance, they incorporated religious rituals with every activity, thus transferring to the collective faith the responsibility for proper functioning of the recharging mechanism. We use some cases from the Americas to elucidate different techniques our ancestors employed in recharging groundwater. These technologies have a great potential for today's water-stressed watersheds, but only after adapting them to local conditions.
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Managing water is a grand challenge problem and has become one of humanity’s foremost priorities. Surface water resources are typically societally managed and relatively well understood; groundwater resources, however, are often hidden and more difficult to conceptualize. Replenishment rates of groundwater cannot match past and current rates of depletion in many parts of the world. In addition, declining quality of the remaining groundwater commonly cannot support all agricultural, industrial and urban demands and ecosystem functioning, especially in the developed world. In the developing world, it can fail to even meet essential human needs. The issue is: how do we manage this crucial resource in an acceptable way, one that considers the sustainability of the resource for future generations and the socioeconomic and environmental impacts? In many cases this means restoring aquifers of concern to some sustainable equilibrium over a negotiated period of time, and seeking opportunities for better managing groundwater conjunctively with surface water and other resource uses. However, there are many, often-interrelated, dimensions to managing groundwater effectively. Effective groundwater management is underpinned by sound science (biophysical and social) that actively engages the wider community and relevant stakeholders in the decision making process. Generally, an integrated approach will mean “thinking beyond the aquifer”, a view which considers the wider context of surface water links, catchment management and cross-sectoral issues with economics, energy, climate, agriculture and the environment. The aim of the book is to document for the first time the dimensions and requirements of sound integrated groundwater management (IGM). The primary focus is on groundwater management within its system, but integrates linkages beyond the aquifer. The book provides an encompassing synthesis for researchers, practitioners and water resource managers on the concepts and tools required for defensible IGM, including how IGM can be applied to achieve more sustainable socioeconomic and environmental outcomes, and key challenges of IGM. The book is divided into five parts: integration overview and problem settings; governance; socioeconomics; biophysical aspects; and modelling and decision support. However, IGM is integrated by definition, thus these divisions should be considered a convenience for presenting the topics rather than hard and fast demarcations of the topic area.
Article
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Abstract For most of the last glacial period, which ended about 10 ka BP2, the temperate forest species were restricted to small areas (termed refugia) with a milder climate, situated mostly along the Mediterranean borderlands and around the Black Sea. Species only started to expand from these glacial period refugia with the large-scale shifts in the global climate in the late- glacial (15-10 ka BP) and the beginning of the Holocene period (10 ka BP to present). Fossil pollen data from sites across Europe have been used to reconstruct the location of refugia of the deciduous oak species, and the spread from these refugia into their current ranges. Three areas of southern Europe have been identified as refugia for deciduous Quercus: southern Iberian peninsula, southern Italian peninsula and the southern Balkan peninsula. The spread of Quercus took place in two steps. First, in the late-glacial interstadial (13-11 ka BP) Quercus spread to the central European mountains from these refugia. Second, with the stabilisation of a climate favourable to deciduous trees species in the Holocene, oak spread into northern Europe, rapidly into the north-west, and more slowly into the centre and east, due to physical barriers. The earlier distribution changes are strongly correlated with the shifts in climate, whereas the later changes are most strongly controlled by competition between species, landscape topography and other edaphic factors. By approximately 6 ka BP, the deciduous oak had reached its maximum extension in Europe. Two types of refugia have been identified from the observed range expansion: primary, full glacial refugia; and secondary, temporary refugia, which supported populations of the oak during the short, climatically unfavourable late-glacial stadial
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