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How efficient are pre-dams as reservoir guardians? A long-term study on nutrient retention in small impoundments
No full textAssessing nutrient loading and processing is crucial for water quality management in lakes and reservoirs. Understanding the fluxes of nutrients through the hydrological pathway and the involved transformations and corresponding retention patterns is therefore important for stakeholders, water managers, as well as researchers. Quantifying and reducing external non-point source nutrient inputs in these systems remains a significant challenge. The difficulty arises primarily from two factors:the low nutrient monitoring frequencies and corresponding difficulties in quantification andthe limited availability of effective instruments to reduce diffuse source loading.One of the few instruments is the operation of pre-dams, i.e. small impoundments at the inflow points into reservoirs, designed to retain nutrients by algal uptake and sedimentation. Although such pre-dams are engineered systems, their biochemical reactivity and corresponding retention capacities are blueprints for any other standing water body embedded in the fluvial continuum. This study tackles the issue by analyzing a long-term (ranging from 8 to 21 years) nutrient and discharge time series for nine German pre-dams. To assess the pre-dams’ retention capacity, we followed a three-step workflow:quantify nutrient loading by using and comparing four mathematical approaches,calculate annual and monthly retention efficiencies for nine pre-dams based on long-term data, andstatistically analyze the major factors determining the retention efficiencies for Nitrogen (N), Phosphorus (P) and Silicon (Si).The results show that soluble reactive phosphorus (SRP) (43.6%) and total phosphorus (TP) (39.9%) mean retention efficiencies are higher than for nitrate (NO3) (15.3%) and silica (Si) (15.9%) retention for all pre-dams. In a few years and pre-dams, there was negative retention of TP, NO3, and Si, and a nutrient release took place. The seasonal variation in retention efficiency demonstrated increased retention rates for SRP and TP during the summer months. Mixed effects models documented a significant influence of the pre-dams’ hydraulic residence time (HRT) (p-value < 0.001) on retention efficiency
Restoration of former peat extraction areas is a key measure to enhance biodiversity and mitigate climate change.
No full textThe restoration of former peat extraction areas offers an opportunity to integrate nature-based solutions (NbS) into post-extraction land use, enhancing carbon sequestration, biodiversity, and water retention. By rewetting degraded peatlands and implementing NbS-based land-use strategies such as wetland creation and Sphagnum moss re-establishment, these areas can regain essential ecosystem functions while contributing to the EU Green Deal’s climate objectives. However, obtaining sciece-based evidence for the long-term success of these measures requires continuous monitoring to assess their effectiveness in reducing greenhouse gas emissions and improving ecosystem resilience.This study examines how different post-extraction land-use options affect water quality, greenhouse gas emissions, and biodiversity in the former Komppasuo peat extraction area. Baseline measurements were conducted before restoration, and ongoing monitoring tracks the site's recovery into a carbon sink. Key methods include hydrological monitoring, greenhouse gas flux measurements, and standardized vegetation and bird surveys. Active and passive vegetation reintroduction and optimized water level management have been tested to reduce peat decomposition. Drone imagery has been used to monitor spatial changes, providing valuable insights into vegetation development and wetland formation dynamics.Results show that vegetation recovery has progressed rapidly, especially in ash-treated areas, where the pre-treatment has enhanced plant establishment. Wetland habitats have developed diverse ecological conditions, supporting increased species diversity and altering bird community composition. The introduction of water level management structures has facilitated hydrological stabilization, but further adjustments may be needed to optimize conditions for peat-forming vegetation. Initial greenhouse gas data indicate that CO₂ emissions have decreased, but methane fluxes remain variable and require further long-term monitoring to determine net climate effects. Water quality results show that restoration has increased nutrient loading to downstream waters, and after removing peat extraction-related water protection structures, runoff is more nutrient-rich than during peat extraction. These findings underline the importance of site-specific management strategies to minimize unintended environmental impacts while maximizing restoration benefits.Peatland restoration requires balancing multiple, sometimes conflicting, objectives. Hydrological restoration can improve carbon sequestration potential but may temporarily increase methane emissions and nutrient leaching. Long-term monitoring is essential to determine whether degraded peatlands can become carbon sinks and how different land-use strategies influence this process. A critical zone approach is needed in the monitoring framework to fully understand complex interactions between hydrology, soil processes, vegetation dynamics, and greenhouse gas fluxes. Restoring hydrological connectivity is particularly important for ensuring long-term ecosystem recovery and stability
Land use change impacts on H2O and CO2 surface/atmosphere fluxes derived from two Eddy-Covariance stations under sudanian climate in West Africa
No full textEcosystem capacity studies for carbon sequestration and water extraction are largely conditioned by Eddy Covariance (EC) measurement availability and quality. According to the FluxNet map, West Africa is one the less instrumented continent. This geographical gap leads to large uncertainties in the world carbon Budget. For decades several experiments have been led in Africa but they remain parsimonious with low visibility often because of short time series, associated with time limited project. In this context, several ongoing initiatives aim at structuring the Eddy-Covariance African community that is emerging. Among them, the West African Flux Network (WAF-Net) has been created to structure the West African Flux community together with their “Northern” partners. Among others, one of the WAF-Net partners in Benin has been active for more than 15 years at providing Eddy-Covariance fluxes over several ecosystems. This network aims at documenting land use variability and trends in West Africa. After an introduction of this new context, the presentation will focus on the analysis of the Beninese Eddy Fluxes for H2O and CO2 over two major ecosystems in Benin, a mixed crop savannah (Nalohou, lat. 9.74°N, long. 1.60°E) and a clear forest (Bellefoungou, lat. 9.79°N, long. 1.72°E), using data spanning from 2007 to 2024. In terms of methodology, we had to develop specific processing to account for, among others, dust deposit, roughness and displacement height estimations, ground heat flux and Respiration of the Ecosystem (RECO) calculations, as for data qualification. This results in the longest EddyFlux time series in West Africa to document the role of evapotranspiration in the water hydrological cycle, and the CO2 sink capacity of West African Ecosystems. From this long time series, we explore the inter annual variability and derive averaged annual H2O and CO2 budgets and their associated variability. Knowing the land conversion area in the region since the seventies (~20% of the total surface has been converted), this allows us to estimate the losses and changes in sequestration capacity (~8%) and water extraction (~-4%) by sudanian ecosystems in this dry tropical climate environment.The WAF-Net community, together with other African flux groups, are building the future of Eddy Flux measurements in Africa. They are leading new projects to develop new stations and to produce new Eddy-covariance data to understand better the tropical ecosystems functioning and further on reduce the uncertainties in the African greenhouse gas budget
Spatio-temporal mapping of aquatic ecosystems by long-term monitoring and citizen science
No full textAccording to the United Nations Educational, Scientific and Cultural Organization (2024), the quality and quantity of water available for all our uses will become the major challenge of the 21st century. Increased temperatures, problems of oxygenation, (micro)pollutants concentrations are some of the problems to be dealt with, whose consequences are many, not only for livestock farming, fishing and aquatic biodiversity, but also for drinking water production.In Europe the Water Framework Directive (WFD) aims to assess the ecological and chemical status of surface waters at the level of the river basin district (i.e., “an area of land and sea, comprising one or more river basins and associated groundwater and coastal waters, identified as the main unit for the purposes of river basin management”). Small streams, typical of watershed headwaters, are not monitored in the WFD. However, they are estimated to account for up to 80% of the total hydrographic length in a river watershed, making a major contribution to the water supply of downstream ecosystems (MacDonald and Coe 2007).Since 2010, the LTSER Zone Atelier du Bassin de la Moselle has been involved on the long-term monthly monitoring, with the help of forest rangers, of an initial set of 16 pristine headwater streams in the Vosges Mountains (https://acev.otelo.univ-lorraine.fr/ , https://deims.org/22915474-7c50-47c1-8239-6c59fa924a1b). These streams are running on granite or sandstone soils in forests dotted with wetlands of various size. The monitoring stations are upstream of any anthropogenic activity, except forestry and extensive tourism. This initial set has been progressively expanded with other nearby streams. However, all of them belong to the same mountainous typology.With this in mind, a participatory research project, O'CitEaux (https://ociteaux.fr/), has been set up to monitor the quality of small rivers in a wider context, using new low-cost sensors. We believe in the importance of such monitoring in the face of climate change (Whyte et al. 2024, von Gönner et al. 2024). Together with an increase of temperature, longer periods of drought interspersed with episodes of heavy rainfall are expected in the coming decades. The flow of small rivers and the quality of their water are therefore likely to be significantly altered. The O'CitEaux participants are:fishing association members (A),primary and secondary school teachers and their students (B), orjust people interested in quality of the aquatic environment (C).Participants A and B are equipped with a low-cost water case which enables them to measure pH, conductivity and temperature in-situ and in the future dissolved organic matter (Ritson et al. 2014). Participants A measure the water level and the width of the watercourse, which can be used for estimation of the discharge rate after proper calibration. All participants collect water samples (one-shot or on a monthly basis, depending upon their level of implication), filtrate them and send them immediately to the research laboratory. Additional information about the location of the station and its immediate surroundings, as well as on biodiversity (odonata, fish, etc.), is collected.Samples collected either by researchers or by O'CitEaux participants follow the same analysis process: filtration at 0.45 µm, analysis of dissolved organic and inorganic carbon, dissolved total nitrogen and major anions and cations, DOM spectral characteristics by UV-visible spectroscopy (aromaticity and molecular weight scoring) and fluorescence spectroscopy (DOM humification, etc.).To date, 150 streams (mainly in France, UK and Scandinavia) have been sampled (i.e., 400 samples) in addition to the 40 streams monitored directly by the researchers on a monthly basis (Fig. 1). The variety of their typology is shown in Fig. 2: high dissolved inorganic carbon concentrations reflect rivers running on calcareous soils, when high dissolved organic carbon concentrations characterized rivers influenced by forests and peatlands.The presentation will discuss the water quality results in function of geology, land use and season and compare them to WFD data collected at a larger scale. An example of data analysis is shown in Fig. 3 for dissolved nitrogen, with a gradient between the forested Vosges Mountains and the western zone where agriculture is more intensive. Citizen involvement (motivation, effectiveness, fear of doing the wrong thing, etc.) will be discussed as well as the best ways for feedback (database, website, counseling)
The ecological importance of temporary ponds, especially vernal pools for waterfowl breeding success
No full textIn Fennoscandia, waterbirds have declined over several decade, and this decline could be linked to problems in the breeding success and loss of foraging habitat provided by wetlands. Availability of aquatic invertebrates is crucially important for ducks during the breeding season, and especially for young ducklings. However, the relationship of invertebrate food resources on duckling growth and survival is not very well understood. In this research, we used imprinted mallard ducklings (Anas platyrhynchos, 1758) to study the effect of the availability of aquatic invertebrates on duckling growth. At hatch, ducklings were divided into two different groups and assigned to forage either on permanent (lakes) or temporary (pools) wetlands. Each day, ducklings were brought to the study sites for four hours to forage. Ducklings were weighed before and after the foraging period. Aquatic invertebrates were sampled with activity (macroinvertebrates and zooplankton) and emergence traps (aquatic emerging insects). The ducklings gain more weight in temporary ponds, and this was associated with the availability of macroinvertebrates. Temporary ponds had higher aquatic macroinvertebrate abundance than the permanent lakes. However, no significant relationship was found between duckling weight and abundance of emerging insects or zooplankton. We highlight the crucial role of aquatic invertebrates in ducklings’ mass gain and emphasize the importance of temporary wetlands during the brood rearing period for the breeding success of ducks
GTK’s HYGLO WOLL stations - A Living Lab for Groundwater Research
No full textHYGLO WOLL is a network of nine hydrogeological test sites in Finland Fig. 1 operated by Geological Survey of Finland (GTK). These sites are part of Water Europe’s living laboratory network (Water Europe 2025) for innovative, international groundwater research.Through automated data collection and regular groundwater sampling, HYGLO WOLL test sites (established in 2022-2023) provide a platform to study the impacts of global change on groundwater resources in subarctic and arctic regions. Each HYGLO WOLL test site has its own research questions, which the data collection aims to better understand. The key research questions include understanding the groundwater – surface water interaction, evaluating the effectiveness of aquifer recharge, and studying the impact of human activities like mining and forestry on groundwater quality and quantity. Additionally, the monitoring data is used to study the role of groundwater in the carbon cycle. Two of the HYGLO WOLL test sites – Lammi and Oulanka – belong to the European LTER sites. Lammi The HYGLO WOLL Lammi station is located in Lammi, in the Eastern part of Hämeenlinna municipality, near the border of Päijänne-Tavastia. The main study area covers about 30 hectares and contains preserved broad-leaf woodlands, agricultural fields and the Biological Research Station of Lammi (Lammi LTER 2025), owned by the University of Helsinki. The aim of the Lammi test site is to produce new hydrogeological knowledge of till lands containing shallow groundwater aquifers. Till (moraine) is the most abundant sediment in Finland and, as such, presents the most common geological environment for small household wells. The geological setting in the overall area is dominated by II Salpausselkä, an extensive ice-marginal ridge system which, genetically, is a wide terminal moraine formation that formed during the Younger Dryas period (approx. 11,790-11,590 years ago). In the study site the soil is mostly consisted of typically coarse-grained till which has widely been covered by a thinner, more fine-grained sedimentary unit. The overall sediment thickness in the study area is rarely more than 10 meters. The bedrock is granodioritic and considered as aquitard. Aquifer in the area is shallow, with a near-surface water table and saturated depth of only few meters in general. The HYGLO WOLL Lammi station was established 2022. Remotely-readable CTD (conductivity, temperature and depth) -sensors were installed in 4 groundwater monitoring wells. Biannual sampling campaigns include in situ measurements, as well as groundwater and surface water sampling with a wide range of hydrogeochemical analytics and stabile isotopes. OulankaThe sediments of the Oulanka test site at Haaralamminkangas aquifer consist of Late Weichelian glacial sediments, fine-grained basin sediments, valley delta sand deposits, sandy gravels of the braided river system, and fine-grained flood sediments. River Oulankajoki and the aquifer are in interaction. The bedrock is dolomite rock. The HYGLO WOLL Oulanka station was established 2022. Remotely-readable CTD (conductivity, temperature and depth)-sensors were installed in 5 groundwater monitoring wells in total. There has been one sampling campaign a year including in situ measurements, as well as groundwater and surface water sampling with a wide range of hydrogeochemical analytics, stabile isotopes and microbiology. From 2025 there will be biannual sampling campains in Oulanka as well. In addition to HYGLO WOLL data collection the Oulanka research station (Oulanka LTER 2025) has its own weather monitoring, which measures precipitation, temperature, wind speed, air pressure, atmospheric humidity and long-wave radiation. Furthermore, there is monitoring of the snow water equivalent and depth of the snow in the area. Soil temperature and water content are also monitored in the study area. Oulanka 3D model was generated to visualize sedimentary structures and the hydrogeological properties. Puukkosuo 3D model was constructed to visualize the humification levels in peat. Co-operation In collaboration with the local partners, water utilities, universities, research stations, municipalities, regional governmental agencies, governmental institutes and forestry company, GTK will gather and share data to enhance understanding of groundwater systems in changing climate. This collaborative approach enables us to develop innovative solutions for sustainable water resource management and supports data-based decision-making. Together with existing and forthcoming partners and collaborators GTK will actively develop the HYGLO WOLL network
High frequency data from in-situ sensors as a support to long-term ecological research on aquatic ecosystems
No full textLake Maggiore is a site of the Italian and European Long-Term Ecological Research (LTER) network. It belongs to deep subalpine Lake District in Northern Italy, including lakes Lugano, Como, Garda and Iseo. Lake Maggiore has been monitored for physical, chemical, and biological features since the 1980s in the framework of the limnological campaigns funded by the International Commission for the Protection of Italian-Swiss Waters (CIPAIS). Starting from the 1990s, the lake recovered from eutrophication thanks to remediation measures and reached the present oligotrophic condition. In the last two decades, climate change turned out to be the main driving factor for the long-term evolution of the lake, affecting thermal and hydrodynamical features, oxygen status, nutrient levels and distribution and biological communities (Rogora et al. 2021).In 2020 a high frequency monitoring (HFM) system consisting of a limnological buoy (LM1) equipped with sensors for meteorological and limnological variables and algal pigments was developed and tested in the framework of an EU Interreg project between Italy and Switzerland focusing on lake quality monitoring as a critical input for successful lake management (Tiberti et al. 2021). The buoy was deployed in the Pallanza basin of Lake Maggiore, anchored at a depth of about 40 m. The system was complemented in 2024 by a second monitoring buoy (LM2) in the Ispra basin of the lake. Present activities of HFM data collection, validation and management are continued under the PNRR-ITINERIS (Italian Integrated Environmental Research Infrastructures System) funded by Next Generation EU.Both LM buoys are equipped with a weather station, a thermistor chain (13 and 11 thermistors for LM1 and LM2, respectively) to measure the water temperature profile and sensors for pH, conductivity, dissolved oxygen, and algal pigments (chlorophyll a (Chl-a), phycocyanin (PC) and phycoerythrin (PE)) at about 1.5 m depth. LM1 buoy has an additional Chl-a sensor at about 8 m depth and a live webcam. All sensors are connected to the electronic control unit, which has been specifically designed within the project for the signal acquisition, data storage, basic data elaboration and a wireless data transfer. For further details on the system see Tiberti et al. (2021).Data gathered by the sensors are subject to quality control, also through a regular comparison with discrete data collected by long-term monitoring. During the first two years, we tested the performance of the fluorometric sensors by comparing HFM data with those obtained by traditional methods for the assessment of algal pigments and phytoplankton biomass (Rogora et al. 2023). The test results and the data collected in the following years confirmed in-situ sensors as reliable systems to describe the short-term variability of algal pigments and the use of these data as a proxy of the seasonal pattern of phytoplankton biovolume. As an example, sensor data provided insights into the length and intensity of short lived events, such as the regularly occurring spring diatom blooms or the rapid algal bloom events that cannot easily be captured by the monthly sampling.A further example of the usefulness of the HFM system in Lake Maggiore was the chance to get data when field monitoring was not allowed for technical or logistic constraints, e.g. unfavourable weather conditions, malfunctioning or unavailability of the boat or other equipment. In 2020, during the pandemic period, the long-term monitoring program was forced to stop for a few months; however, some basic but important limnological data were guaranteed by the HFM system, avoiding significant gaps in the time series.Data collected through the HFM system proved to be fundamental in the assessment of climate change impact on Lake Maggiore, particularly of extreme weather conditions. Surface water temperature measured by the buoys in the last few years reached values as high as 30 °C. Even if a direct comparison of the buoy data with those collected in previous years by different systems (e.g., discrete profiles with multiparameter probe) must be done with caution, the extreme temperatures measured in recent years are presumably the highest values ever recorded in Lake Maggiore surface water.The drought of 2022 in Northwestern Italy provided a tremendous example of a condition affecting water resources and the services they provide. In Lake Maggiore area, a combination of scarce snow accumulation in winter and lack of precipitation in spring resulted in an unusual low water level in spring and summer. HFM data put in evidence an unprecedented increase of conductivity in surface water, due to solute concentration. The seasonal pattern of Chl data from HFM in 2022, compared with the previous years, showed low concentration throughout the summer period (June-Aug; Fig. 1). Data from discrete monitoring indicated a higher than average water transparency in 2022 and confirmed low phytoplankton biomass in late spring and summer, and a limited seasonality overall. We hypothesized that scarce precipitation caused a reduced nutrient influx from the watershed, which was indeed confirmed by the monitoring of catchment loads. This condition, coupled with the lack of nutrient replenishment from the deep water during winter because of the increasing stability of the water column, fostered an enhanced oligotrophic condition in summer.These examples demonstrate how HFM, used in conjunction with discrete monitoring, represents an important support to long-term studies on aquatic ecosystems, providing useful insights into ecological processes in response to global change
Easy access to (Dutch) Wadden Data & information
No full textBasismonitoring Wadden is an initiative to obtain an integrated, system-oriented view of the condition and trends in this unique natural area. We are a collaboration of various (governmental) organizations who contribute to monitoring the Wadden Area. From nutrients and benthos to comprehensive well-being of inhabitants. The Dutch Wadden Sea is an LTSER site (LTSER Dutch Wadden Sea Area - Netherlands | DEIMS-SDR). It itself consists of intertidal mudflats and subtidal areas. The southern border of the area consists of inhabited polders, many of which consist of reclaimed saltmarsh areas. The Dutch Wadden Sea is part of the international Wadden Sea, extending along the coasts of Denmark, Germany and the Netherlands. The international Wadden Sea comprises the largest tidal flats system in the world.Our aim is to provide insight into the condition and trends of the Wadden Sea area and to promote effective and efficient monitoring. We are involved in het Expert Group Data of the Trilateral Monitoring and Assenment Program to enhance data sharing between the three Wadden countries.We make Wadden data findable and accessible in a “Waddenregister” with Datahuiswadden.nl as a starting poin
Identifying processes impacting groundwater level at local scale through lumped modelling based investigations: a case study of the Upper Rhine alluvial cross-border aquifer.
No full textThe quaternary alluvial aquifer system in the Upper Rhine Valley, located in northeastern France and southwestern Germany, across the French-German border, is one of Europe's largest freshwater reserves. This aquifer system, which is essential for local anthropic uses, also plays a vital role in supplying water to numerous ecosystems due to the phreatic nature of its groundwater. Additionally, the hydrographic network of the alluvial plain is very dense and characterised by strong groundwater – surface water interactions, influenced by seasonal dynamics. The Interreg GRETA project (GRoundwater EvoluTions and resilience of Associated biodiversity - Upper Rhine) arises from the increasing climatic and anthropogenic pressures on the environment, focusing on the southern part of the Upper Rhine Graben aquifer. Its objectives are to provide key knowledge on the impact of climate change on the quantitative dynamics of the water table and the associated consequences for ecosystems by adopting an integrated approach to the system studied, at the heart of the critical zone.In order to study piezometric variations at different points in the Upper Rhine aquifer, around fifty lumped models have been developed using GARDENIA, a modelling tool developed and updated by BRGM (French Geological Survey). However, given the specificities of the groundwater in the Upper Rhine Valley (shallowness, high hydraulic conductivity of 10-4 to 10-3 m/s (Majdalani and Ackerer 2010), anthropic management of the hydrographic network, water abstraction for irrigation, etc), it is essential to identify the main driving forces behind groundwater dynamics locally and to include these drivers in the modelling tools used to establish hydrogeological projections under a future climate. GARDENIA uses a series of reservoirs to simulate the main mechanisms of the water cycle of a catchment (rainfall, evapotranspiration, infiltration and run-off) (Thiéry 2014). This model considers a global ‘input’ (an ‘incoming water level’ in the basin and potential evapotranspiration) and a single ‘output’, which is, in this case, the piezometric level at a point in the underlying water table.Transfers from one reservoir to another are governed by simple laws that are specific to each reservoir and controlled by model parameters (soil capacity, transfer times, groundwater specific yield, etc.). These parameters cannot be deduced a priori from the specific physiographic characteristics of the catchment and are calibrated through adjustment to observation time series. A baseline model considering only climatic inputs has been applied to all points. Then, based on the Nash–Sutcliffe model efficiency coefficient and on visual inspection, several different model configurations were tested on the points where the initial model results were unsatisfactory. These new models were constructed by adding new potential driving forces as inputs such as a proxy for vegetal water demand or flowrates of the Rhine or other rivers located near observation points.Calibrated models show good results in reproducing historic groundwater levels and allow to identify the main local driving factors of the groundwater dynamics. Further analysis of the influence function weight associated with each additional process over rainfall and potential evapotranspiration allows to decipher first order contributions of the added processes (summer withdrawals or river contributions).In the GRETA project, convolutional neural network models were also built at the observation points database. Initial comparison results show that both methods are valuable for building local hydrogeological models that consider interactions with surface water or land use.These lumped models can then be fed with climatic or hydrological time series estimated in the context of climate change, to be discussed in relation to the ecological monitoring conducted on a selection of pilot sites and upscaled in the study area to assess the impact of changes in piezometry on the associated ecosystems
Functional Restoration of Desertified Ecosystems: Insights from Isreal Negev Desert Experience
No full textEcological restoration has increasingly shifted focus towards restoring ecosystem functions rather than attempting to recreate original, pre-disturbance conditions. This approach, known as functional restoration, prioritizes the rehabilitation of key processes that sustain ecosystems. Functional restoration is especially relevant in severely degraded landscapes, such as desertified regions, where full restoration to the original state is often unfeasible.This study presents a conceptual model outlining the core processes that regulate ecosystem functions in water-limited ecosystems, derived from long-term research conducted in the Negev Desert (Dor-Haim et al. 2023). The model highlights the interconnections and feedback loops that drive the productivity and biodiversity of runoff-dependent dryland ecosystems. Hydrological processes, specifically rainfall-runoff dynamics, are central to the distribution of soil moisture, which, in turn, governs the system's functionality.The model identifies two primary feedback loops:The source feedback loop (biocrust-soil moisture interaction): Biological soil crusts (biocrusts) regulate water infiltration and runoff, capturing rainfall and redistributing it as runoff to other parts of the ecosystem. This process creates hydrological niches with varying moisture levels, which support adjacent patches of woody vegetation and herbaceous plants.The sink feedback loop (woody vegetation-soil interaction): Woody vegetation improves soil properties by contributing organic matter and providing shade, reducing evaporation and maintaining soil moisture. This positive feedback enhances the productivity of vegetation and supports associated species.The balance between the source feedback loop (biocrust) and the sink feedback loop (woody vegetation) is crucial for sustaining the system's overall productivity and biodiversity. Imbalances, such as excessive runoff without sufficient sinks, can lead to soil erosion, while inadequate runoff reduces water availability and productivity. Maintaining this balance is essential for ensuring the ecosystem's resilience to external pressures, including climate change and anthropogenic disturbances.The Negev Desert serves as a compelling case study to test and apply this model in the field. A large-scale project known as "Savanization" employed this framework to create a human-designed landscape in desertified areas, leveraging source-sink feedbacks as a nature-based solution. This functional restoration approach resulted in a novel man-made landscape combining planted trees and natural vegetation, delivering a wide range of ecosystem services.Based on this experience, we developed a set of guiding principles for the functional restoration of degraded landscapes, encompassing four key steps:Identifying fundamental processes that regulate ecosystem functions in alternative states;Detecting the drivers of degradation that disrupt these processes;Implementing functional restoration by transitioning degraded landscapes into functional states;Monitoring and assessing success through measurable impacts on ecosystem services.Our case study in the Negev Desert offers valuable insights into reversing desertification in water-limited ecosystems by restoring source–sink networks. These principles provide a robust framework for guiding functional restoration efforts and enhancing ecosystem resilience, which is critical for addressing the challenges of the Anthropocene