Search Results (31)

Innovative solutions are needed for urban flooding exacerbated by climate change. In light of this, this study developed an integrated framework for urban wetland flood control that combines Morphospatial Pattern Analysis (MSPA), minimum cumulative resistance (MCR) modeling, and complex network theory for optimizing an ecological network of flood control and mitigation wetlands in Changchun, China. The results show that the optimized ecological network significantly improved connectivity and flood mitigation efficiency. The node degree increased from 2.737 to 3.433, and the average clustering coefficient exhibited an increase from 0.074 to 0.231, enhancing material flow efficiency. Robustness analysis revealed that the optimized network’s connectivity robustness improved by 12.6%, 18.4%, and 24.1% under random, malicious, and controlled attack scenarios, respectively. Additionally, ecological corridors with a width of 30–50 m were identified as the optimal range for water conveyance potential, effectively dispersing peak runoff and reducing flood risk. This study provides both a transferable methodology for flood-resilient planning and specific policy actions, including priority conservation of high-betweenness nodes and restoration of fragmented wetlands, offering practical solutions for high-density cities facing similar climate challenges. Full article

As a critical intervention for enhancing inland navigation efficiency, waterway regulation projects profoundly modify riverine hydrodynamic conditions while optimizing navigability. This study employs the MIKE21 hydrodynamic model to establish a two-dimensional numerical framework for assessing hydrological alterations induced by channel regulation in the Hui River, China. Through comparative simulations of pre- and post-project scenarios across dry, normal, and wet hydrological years, the research quantifies impacts on water levels, flow velocity distribution, and geomorphic stability. Results reveal that channel dredging and realignment reduced upstream water levels by up to 0.26 m during drought conditions, while concentrating flow velocities in the main channel by 0.5 m/s. However, localized hydrodynamic restructuring triggered bank erosion risks at cut-off bends and sedimentation in anchorage basins. The integrated analysis demonstrates that although regulation measures enhance flood conveyance and navigation capacity, they disrupt sediment transport equilibrium, destabilize riparian ecosystems, and compromise hydrological monitoring consistency. To mitigate these trade-offs, the study proposes design optimizations—including ecological revetments and adaptive dredging strategies—coupled with enhanced hydrodynamic monitoring and riparian habitat restoration. These findings provide a scientific foundation for balancing navigation improvements with the sustainable management of fluvial systems. Full article

Collecting fog water is crucial for dry areas since natural moisture and fog are significant sources of freshwater. Sustainable and energy-efficient water collection systems can take a page out of the cactus’s playbook by mimicking its native fog gathering process. Inspired by the unique geometric structure of the cactus spine, we fabricated a bioinspired artificial fog collector consisting of cactus spines featuring barbs of different sizes and angles on the surfaces for water collection and a series of microcavities within microchannels inspired by Nepenthes Alata on the bottom to facilitate water flowing to the reservoir. However, replicating the actual shape of the cactus spine using conventional manufacturing techniques is challenging, and research in this area has faced a limitation in enhancing water-collecting efficiency. Here, we turned to 3D printing technology (vat photopolymerization) to create bio-mimetic fog collectors with a variety of geometric shapes that would allow for the most effective conveyance and gathering of water. Various barb sizes, angles between each barb in a single array, spine and barb arrangements, and quantity of barbs were tested experimentally and numeric analysis was carried out to measure the volume of water collected and optimize the mass rate. The result shows that optimal fog collection is with a mass flow rate of 0.7433 g/min, with L_i = 900 μm, θ = 45°, ϕ = 90°, N_b = 2, and N_s = 5. This study presents a sustainable and ecologically sound method for efficiently collecting humid air, which is expected to be advantageous for the advancement of future-oriented fog-collection, water-transportation, and separation technologies. Full article

As China’s largest inland river basin and one of the world’s most arid regions, the Tarim River Basin is home to an extremely fragile ecological environment. Therefore, monitoring the water storage changes is critical for enhancing water resources management and improving hydrological policies to ensure sustainable development. This study reveals the spatiotemporal changes of water storage and its driving factors in the Tarim River Basin from 2002 to 2022, utilizing data from GRACE, GRACE-FO (GFO), GLDAS, the glacier model, and measured hydrological data. In addition, we validate GRACE/GFO data as a novel resource that can monitor the ecological water conveyance (EWC) benefits effectively in the lower reaches of the basin. The results reveal that (1) the northern Tarim River Basin has experienced a significant decline in terrestrial water storage (TWS), with an overall deficit that appears to have accelerated in recent years. From April 2002 to December 2009, the groundwater storage (GWS) anomaly accounted for 87.5% of the TWS anomaly, while from January 2010 to January 2020, the ice water storage (IWS) anomaly contributed 57.1% to the TWS anomaly. (2) The TWS changes in the Tarim River Basin are primarily attributed to the changes of GWS and IWS, and they have the highest correlation with precipitation and evapotranspiration, with grey relation analysis (GRA) coefficients of 0.74 and 0.68, respectively, while the human factors mainly affect GWS, with an average GRA coefficient of 0.64. (3) In assessing ecological water conveyance (EWC) benefits, the GRACE/GFO-derived TWS anomaly in the lower reaches of the Tarim River exhibits a good correspondence with the changes of EWC, NDVI, and groundwater levels. Full article

In an arid climate with minimal rainfall, plant growth is constrained by water scarcity and soil salinity. Ecological Water Conveyance (EWC) can mitigate degradation risks faced by riparian plant communities in these regions. However, its effects on long-term dynamics of root zone soil water content, salt levels, and root water uptake remain unclear. This study examined how groundwater affects salt and water dynamics, in addition to root water uptake, under different scenarios involving Tamarix ramosissima Ledeb. The research was conducted in the lower reaches of the Tarim River in northwestern China. The Hydrus-1D model was used, following the EWC strategy. The results show that the distribution of T. ramosissima roots was significantly influenced by soil water and salt distributions, with 56.8% of roots concentrated in the 60–100 cm soil layer. Under water stress conditions, root water uptake reached 91.0% of the potential maximum when considering water stress alone, and 41.0% when accounting for both water and salt stresses. Root water uptake was highly sensitive to changes in Depth-to-Water Table (DWT), notably decreasing with lower or higher DWT at 40% of the reference level. EWC effectively enhances root water uptake by using water to leach salts from the root zone soil, with optimal results observed at 500–600 mm. This study advocates for sustainable EWC practices to support vegetation and combat desertification in the lower reaches of arid inland rivers. Full article

Taitema Lake, situated at the terminus of the Tarim River Basin in Northwest China, represents a crucial ecological resource impacted by climate variability and anthropogenic interventions. In this study, we investigate the dynamic changes in Taitema Lake’s area and water quality resulting from the implementation of an ecological water transfer project in 2000. Leveraging Landsat remote sensing data and comprehensive water quality monitoring, we analyzed the relationship between lake area variations and shifts in water quality parameters. Notably, our findings reveal a significant increase in Taitema Lake’s area from 9.4 km² in 2000 to 320 km² in 2013. Concurrently, water quality indicators exhibited marked fluctuations, with total salt content ranging from 45,323.6 mg/L in 2000 to 970.4 mg/L in 2010 before increasing to 14,586.3 mg/L by 2014. Furthermore, a linear regression analysis highlights the moderate positive correlation between lake area and mineralization (R² = 0.506) and sodium levels (R² = 0.4907). Additionally, chloride (R² = 0.5681) and sulfate (R² = 0.6213) concentrations demonstrated a strong negative correlation with the lake area, indicative of a dilution effect. Furthermore, a comparison of water quality indicators between the years of minimum (2008) and maximum (2013) lake area underscores improvements in pH, chemical oxygen demand, and anionic surfactant concentrations as the lake area increased. Our study provides valuable insights into the effectiveness of ecological water management strategies in restoring and maintaining the ecological health of Taitema Lake, thereby informing evidence-based decision-making for the sustainable management of freshwater resources in arid environments. Full article

The practice of stormwater management has evolved from a singular focus on drainage to a multifaceted approach to support the integrated urban development of healthy, livable, ecological, and water sensitive cities from neighborhood to metropolitan scales. A review of the knowledge base and practice by the professional stormwater management community shows attributes that favor an integrative approach to achieve co-benefits across sectors. Research into stormwater management addresses its functional areas of drainage, flood control, flood plain management, water quality control, urban ecology, recreation, and city beautification. Legacy path dependance affects the potential to reform land use practices, while stormwater management practice is affected by climate change, sea level rise, urbanization, inequality, and poor governance. This review shows a status where technical methods are well advanced but integrative frameworks to address social, ecological and infrastructure needs are more challenging. The sensitivity of ecological issues is most evident in cities in coastal zones. Organizational initiatives are needed to counter the neglect of essential maintenance and sustain flood risk reduction in cities. Stormwater management is related to other integrative tools, including IWRM, One Water, One Health, and Integrated Flood Management, as well as the broader concept of urban planning. This research review demonstrates the opportunities and needs for the advancement of an integrated approach to stormwater management to support urban development. Stormwater capture and rainfall harvesting offer major opportunities to augment scarce water supplies. Nature-based solutions like low-impact development and the sponge city concept show promise to transform cities. Major cities face challenges to sustain conveyance corridors for major flows and to store and treat combined sewer runoff. The neighborhood focus of stormwater management elevates the importance of participation and inclusion to advance environmental justice and strengthen social capital. Integrating organizational initiatives from local to city scales and funding improvements to stormwater systems are major challenges that require leadership from higher governance levels, although governments face resistance to change toward integration, especially in countries with poor land use and public works management systems. Finding solutions to neighborhood issues and the connectivity of water systems at larger scales requires complex approaches to urban planning and represent an important agenda for urban and water governance going forward. Full article

The Amapá margin, part of the Brazilian Equatorial Margin (BEM), is a key region that plays a strategic role in the global climate balance between the North and South Atlantic Ocean as it is strictly tied to equatorial heat conveyance and the fresh/salt water equilibrium with the Amazon River. We performed a new scientific expedition on the Amapá continental shelf (ACS, northern part of the Amazon continental platform) collecting sediment and using instrumental observation at an unstudied site. We show here the preliminary outcomes following the applied methodologies for investigation. Geophysical, geological, and biological surveys were carried out within the ACS to (1) perform bathymetric and sonographic mapping, high-resolution sub-surface geophysical characterization of the deep environment of the margin of the continental platform, (2) characterize the habitats and benthic communities through underwater images and biological sampling, (3) collect benthic organisms for ecological and taxonomic studies, (4) define the mineralogical and (5) elemental components of sediments from the study region, and (6) identify their provenance. The geophysical data collection included the use of bathymetry, a sub-bottom profiler, side scan sonar, bathythermograph acquisition, moving vessel profiler, and a thermosalinograph. The geological data were obtained through mineralogical, elemental, and grain size analysis. The biological investigation involved epifauna/infauna characterization, microbial analysis, and eDNA analysis. The preliminary results of the geophysical mapping, shallow seismic, and ultrasonographic surveys endorsed the identification of a hard substrate in a mesophotic environment. The preliminary geological data allowed the identification of amphibole, feldspar, biotite, as well as other minerals (e.g., calcite, quartz, goethite, ilmenite) present in the substrata of the Amapá continental shelf. Silicon, iron, calcium, and aluminum composes ~85% of sediments from the ACS. Sand and clay are the main fraction from these sediments. Within the sediments, Polychaeta (Annelida) dominated, followed by Crustacea (Arthropoda), and Ophiuroidea (Echinodermata). Through TowCam videos, 35 taxons with diverse epifauna were recorded, including polychaetes, hydroids, algae, gastropods, anemones, cephalopods, crustaceans, fishes, and sea stars. Full article

P. euphratica stands as the pioneering and dominant tree within desert riparian forests in arid and semi-arid regions. The aim of our work was to reveal why dioecious P. euphratica in natural desert riparian forests in the lower Tarim River exhibits sexual spatial distribution differences combined with field investigation, tree ring techniques, isotope analysis techniques, and statistical analyses. The results showed that P. euphratica was a male-biased population, with the operational sex ratio (OSR) exhibiting spatial distribution differences to variations in drought stress resulting from groundwater depth change. The highest OSR was observed under mild drought stress (groundwater depth of 6–7 m), and it was reduced under non-drought stress (groundwater depth below 6 m) or severe drought stress (groundwater depth exceeding 7 m). As drought stress escalated, the degradation and aging of the P. euphratica forest became more pronounced. Males exhibited significantly higher growth rates and WUE_i than females under mild drought stress. However, under severe drought stress, males’ growth rates significantly slowed down, accompanied by significantly lower WUE_i than in females. This divergence determined the sexual spatial segregation of P. euphratica in the natural desert riparian forests of the lower Tarim River. Furthermore, the current ecological water conveyance project (EWCP) in the lower Tarim River was hard to fundamentally reverse the degradation and aging of the P. euphratica forest due to inadequate population regeneration. Consequently, we advocated for an optimized ecological water conveyance mode to restore, conserve, and rejuvenate natural P. euphratica forests. Full article

The evolution of a terminal lake at the end of a river not only reflects the climate change characteristics within the basin but also the impact of regional human activities, especially in arid areas. In the Hexi Interior of China, three terminal lakes (e.g., Halaqi Lake, East Juyanhai Lake, and Qingtu Lake) situated in the Shule River, Heihe River and Shiyang River, respectively, have been increasingly studied to support regional ecological protection and sustainable oasis development. In this study, Landsat TM/ETM+/OLI and Sentinel-2 MSI imagery were used to examine Halaqi Lake spanning from 2017 to 2022, East Juyanhai Lake from 1990 to 2022, and Qingtu Lake from 2009 to 2022. The focus of this investigation was to characterize changes in lake area and the impact of climate change and human activities. The results revealed a dramatic change in Halaqi Lake, which suddenly emerged in 2017, initially covering an area of 13.49 km², gradually vanishing nearly in 2021, and reappearing in 2022 with a reduced area of 9.53 km². The area of East Juyanhai Lake was 54.39 km² in 1990 but reduced to 40.84 km² by 2022. Throughout this period, it encountered episodes of drying up in 1992, 1995, 2001, and 2002. Qingtu Lake emerged in 2009, with an area of 0.09 km², and subsequently expanded to 2.60 km² by 2022. Climate change and human activities collectively influence the area fluctuations of these three terminal lakes. Among these factors, temperature changes have a greater impact on the lake area in East Juyanhai. Global warming has worsened glacier melting in the Qilian Mountains, resulting in increased inflow in certain years and substantial lake area expansion. Human activities are the primary drivers of changes in Halaqi Lake and Qingtu Lake. Industrial water consumption is the key factor influencing area changes in Halaqi Lake, whereas water usage in forestry, animal husbandry, and fisheries plays a dominant role in the area changes of Qingtu Lake. Furthermore, the introduction of ecological water conveyance projects has had an indispensable effect on rejuvenating and preserving the watershed areas of these three terminal lakes. It is important to emphasize that human-driven water resource management is the primary cause of sudden changes in the lake areas. Full article

In the context of global climate change and the water-carbon peak target, improving water security in arid regions is a persistent challenge in global water resources management. Water diversion projects can serve as an important measure to effectively alleviate the uneven distribution of water resources, achieve rational allocation and efficient utilization of water resources. However, how to achieve the maximization of comprehensive benefits during the process of water allocation is also an urgent problem that needs to be solved. This study focuses on the Middle Route Project of the South to North Water Diversion Project in China, selecting four important municipalities and provinces during 2015 to 2021, namely Beijing, Tianjin, Hebei Province, and Henan Province, based on the actual benefits of the water receiving areas of the middle line project. Nine representative indicators related to social, economic, and ecological benefits were selected to evaluate the optimal combination of water resource allocation in the water receiving areas along the central line, in order to achieve the maximum comprehensive benefits and solve the problems of high water safety guarantee requirements and difficult balanced water distribution in urban agglomerations in the water receiving areas. Through the calculation of the Markovsky theoretical model, the results show that when 79.9% of the water conveyance is used to generate social benefits, 15.8% of the water conveyance is used to generate ecological benefits, and 4.5% of the water conveyance is used to generate economic benefits, the project achieves the maximum comprehensive benefits. This computational model method can be used to provide technical support and scientific reference for the optimal allocation of water resources in cross regional water transfer projects. Full article

In arid regions with scarce water resources, lakes play an extremely vital role in maintaining the ecological environment. Therefore, the Chinese government has launched an ecological water conveyance project in the Tarim River basin in Xinjiang with the aim of restoring the ecological environment of the area. In previous studies, there was no complete evaluation system used to quantify changes in the ecological environment of arid regions after ecological water conveyance. In this paper, Lake Taitema was selected as the study area, which is both a terminal lake in the Tarim River basin and an object of the ecological water conveyance project. This study utilized Landsat TM/OLI satellite remote sensing images and MODIS datasets to build a remote sensing ecological index model and systematically evaluated the changes in the ecological environment and land use types in the Taitema Lake area. A structural equation model was constructed to analyze the correlation between the area of Taitema Lake and its driving factors. The results show that over the selected 20 years, the proportion of pixels with an upward trend (Zc > 0) of the RSEI was 56.5%, while the proportion of pixels with a downward trend (Zc < 0) of the RSEI was 43.5%. The area proportion of regions with poor ecological environment quality decreased by about 40%, and the area proportions of regions with moderate, good, and excellent ecological environment quality increased by 29.7%, 10%, and 0.6%, respectively. By comparing the land use data from 2000 and 2020, the proportion of grassland increased by 6%, the proportion of water area increased by 4.4%, and the proportion of unused land decreased by 9.6%. In summary, after the implementation of the ecological water conveyance project, the ecological environment quality of the Lake Taitema area gradually improved, and ecological water conveyance was the main driving factor of the area change in Lake Taitema. Full article

Basin ecosystems are vulnerable to natural resource depletion, ecological damage, and environmental pollution due to their fragile natural environment. Assessing the value of basin ecosystem services (ES) can facilitate informed decision making by policy makers and stakeholders in the context of competing resource use. The Konqi River Basin in China, an arid inland river basin, has suffered from degraded ecosystems due to overexploitation of soil and water resources. In response, the local government launched an ecological water conveyance (EWC) project in 2016 to enhance ecological restoration efforts. This paper analyzes and evaluates the value of ES in the Konqi River Basin based on land use and land cover (LULC) change characteristics before and after EWC in 2013 and 2020, respectively. Remote sensing data and related socioeconomic statistics data are used to assess a typical river basin from three unique locations in the Konqi River Basin, divided into upper and lower reaches. The results show that cropland and unused land are the most important land use types in the upper and lower reaches. The characteristics of ecosystem service value (ESV) changes in the study area are consistent with land use structure changes. The total ESV shows a decreasing trend in the upper reaches from 2013 to 2020, while the lower reaches show an increasing trend. The total ESV increases in the typical river reaches of the Konqi River Basin. Spatially, low-ESV areas are mainly located in ecologically fragile areas that are difficult to develop and use. The sensitivity indexes of the study area are all less than 1, making the results of this study credible. The Moran index shows a significant spatial correlation in the study area, indicating that the distribution characteristics of high-ESV areas are agglomerative. Hot spot areas in the upper reaches show an overall increasing trend, while in the lower reaches, former sub-hot spot areas transform into hot spot areas. Due to data limitations, this study is limited to demonstrating that the value of ES in the area changes due to a combination of EWC policies and other factors. Nevertheless, the analysis shows that EWC policies actively change the ESV of a typical river basin in Konqi. This study can provide a reference for evaluating ESV in inland river basins in the northwest arid region and a scientific basis for the rational development and utilization of water and soil resources in the study area, located in an arid and ecologically fragile area. Full article

Clarifying the water uptake patterns and competition among riparian plants under different ecological water conveyance conditions is crucial for the stability of the riparian ecosystem in arid areas. Here, we have utilized the Bayesian isotope mixing model to quantify the plant water sources for two typical riparian plants (Tamarix ramosissima and Phragmites australis) along the Manas River in Xinjiang, Northwest China. The water competition relationship between these two typical riparian plants is evaluated using the proportional similarity index (PSI). Our findings demonstrated the following: (1) The climate in the study area is dry and strongly evaporative, and the slope and intercept of the local meteoric water line are smaller than the global meteoric water line. The interconversion between surface water and groundwater occurred mainly in the upper reaches of the river. (2) At the sample site with the long-term ecological water conveyance, the water uptake pattern for typical riparian plants is predominantly shallow soil water or the uniform use of potential water sources. Among them, the utilization rate of shallow soil water reached 30.7 ± 12.6%. At sample sites with intermittent ecological water conveyance and the non-ecological water conveyance sample site, the growth of T. ramosissima and P. australis primarily uses deep soil water and groundwater, with mean values of 34.5 ± 5.1% and 32.2 ± 1.9%, respectively. (3) The water competition between plants at the intermittent ecological water conveyance and non-ecological water conveyance sample sites was more intense. However, the long-term ecological water conveyance effectively reduced water competition among plants. Our results will provide basic theoretical support for maintaining the stability of the Manas River riparian ecosystem and determining environmental flows. Full article

The relationship between soil and vegetation is an essential scientific issue in surface environment change. (1) Background: Since the implementation of the Shiyang River Basin governance plan, it has become necessary to quantitatively evaluate the impact of ecological restoration on soil–vegetation spatial coupling. (2) Methods: A coupled model and a coupled coordination model are adopted in order to investigate the spatial coupling characteristics of soil–vegetation systems. Additionally, we explore the influences of climate factors and soil properties on the level of spatial coupling and coordination. (3) Results: From 2015 to 2020, the soil–vegetation spatial coupling coordination in the lower reaches of the Shiyang River Basin was poor, and the average annual proportion of areas with medium and low degrees of uncoordination reached 79.3%. The level of spatial coupling coordination is differed under different vegetation coverage scenarios, and the bare land mainly showed low and moderate imbalances, accounting for 90.3% of the annual average area. The annual average proportions of short coverage and canopy coverage coordinated areas were 53.4% and 49.3%, respectively. In particular, vegetation in the Minqin hinterland is highly sensitive to environmental changes. With the implementation of ecological water conveyance, the spatial coupling coordination between soil and vegetation has improved slightly; however, the effect is not obvious. (4) Conclusions: Precipitation, temperature, and potential evaporation affect the level of coupling coordination between soil and vegetation, with the former having a positive effect and the latter two having negative effects. In addition, soil enriched with sulfate and sand contributed to the disharmony of soil–vegetation relationships in the study area. Full article