Search Results (59)

The Beijing–Tianjin–Hebei (BTH) region is one of China’s most water-scarce yet economically vital areas, facing increasing challenges due to climate change and intensive human activities. This study develops an integrated Water–Food–Energy–Ecology (WFEE) simulation and regulation model to assess the system’s stability under coordinated development scenarios and extreme climate stress. A 500-year precipitation series was reconstructed using historical drought and flood records combined with wavelet analysis and machine learning models (Random Forest and Support Vector Regression). Results show that during the reconstructed historical megadrought (1633–1647), with average precipitation anomalies reaching −20% to −27%, leading to a regional water shortage rate of 16.9%, food self-sufficiency as low as 44.7%, and a critical reduction in ecological river discharge. Under future recommended scenario with enhanced water conservation, reclaimed water reuse, and expanded inter-basin transfers, the region could maintain a water shortage rate of 2.6%, achieve 69.3% food self-sufficiency, and support ecological water demand. However, long-term water resource degradation could still reduce food self-sufficiency to 62.9% and ecological outflows by 20%. The findings provide insights into adaptive water management, highlight the vulnerability of highly coupled systems to prolonged droughts, and support regional policy decisions on resilience-oriented water infrastructure planning. Full article

Olive trees are generally considered a species well-adapted to drought, but the impact of water shortage is of critical importance on olive production. For this reason, developing tolerant cultivars could be an effective strategy to mitigate the impact of drought in the future. Characterizing drought stress tolerance in olive is a complex task due to the numerous traits involved in this response. In this study, plant growth, pressure–volume curves, gas-exchange and chlorophyll fluorescence traits, and stomata characteristics were monitored in nine cultivars to assess the effects of mild and severe drought stress conditions induced by withholding water for 7 and 21 days, respectively, and were compared to a well-watered control treatment. The plant materials evaluated included traditional cultivars, as well as new developed cultivars suited for high-density hedgerow olive orchards or resistant to verticillium wilt. Significant differences between cultivars were observed for most evaluated traits, with more pronounced differences under severe drought conditions. A multivariate analysis of the complete dataset recorded throughout the evaluation period allowed for the identification of promising cultivars under stress conditions (‘Sikitita’, ‘Sikitita-2’, and ‘Martina’) as well as highly discriminative traits that could serve as key selection parameters in future breeding programs. Full article

Poyang Lake in China is the most critical habitat and final refuge for the Yangtze finless porpoise (Neophocaena asiaeorientalis), YFP. In 2022, its population reached approximately 492 individuals, an increase of 35 from the 457 individuals recorded in 2017, showing a steady upward trend. The infrequent movement of YFPs between Poyang Lake and the Yangtze River represents a considerable threat to the long-term viability of this population. Additionally, serious water shortages in the lake during the dry season have led the government to consider the establishment of a hydraulic project. Therefore, a reliable risk assessment and quantitative analysis of conservation scenarios are urgently needed for this population. Population viability analysis of the YFP population in Poyang Lake was conducted using the VORTEX software. The baseline model predicted a probability of extinction of 0.241 over the next 100 years, with no probability of extinction in the first 30 years; the genetic diversity would be on a continuous downward trend and decline by 91.5%. The comprehensive protection model predicted a probability of extinction of 0.0028 and that the genetic diversity would be maintained at about 0.996 in 100 years. Breeding rate, sex ratio at birth, mortality rate, and gene flow were the factors that were sensitive to maintaining population viability. The results showed that the population of YFPs in Poyang Lake was at a high risk of extinction due to the decline in genetic diversity and the higher mortality and lower birth rate caused by habitat degradation. A total ban on productive fishing and the rescue and interchange of YFPs are conducive to enhancing the viability of the YFP population in Poyang Lake. Full article

Driven by global population growth and resource shortages, the coupled and coordinated development of the “Water-Carbon-Ecology” (W-C-E) nexus has emerged as a crucial factor for sustainable societal development. This study constructs a multidimensional evaluation model for the W-C-E system in the eleven provinces and municipalities of the Yangtze River Economic Belt (YEB), encompassing the richness of individual systems, the coordination between dual systems, and the robustness of the tertiary system. We propose the “W-C-E Nexus Index” (WCENI) to analyze the coupling and coordination levels among the W-C-E systems in these regions from a bottom-up perspective. Utilizing the obstacle degree model and geographical detector model, we explore the impact of key indicators on the coupled and coordinated development of the W-C-E system. The findings reveal the following: (1) The coordination index and robustness index among the three W-C-E subsystems have increased significantly, while the richness index of individual subsystems varies widely among the YEB. (2) During the study period, the WCENI for the YEB rose from 0.351 to 0.391, indicating an overall upward trend in the coupling and coordination among the W-C-E subsystems. Jiangsu recorded the highest average WCENI value of 0.445, topping the list of the eleven regions. (3) The interaction between pairs of driving factors exceeds the influence of any single factor, with per capita water consumption emerging as the primary driver for the coupled and coordinated development of the W-C-E nexus in the YEB, with an average obstacle degree of 12.05%. These findings provide a theoretical basis for regional coordinated management and sustainable development. Full article

The Thessaly Plain, Greece’s largest alluvial basin, has undergone significant geological, hydrological, and anthropogenic transformations. This study synthesises historical records, geological and hydrogeological studies to assess the evolution of the East Thessaly Plain, focusing on land use changes, groundwater management, and environmental challenges. Intensive agricultural practices, particularly from the 1970s onward, have led to groundwater overexploitation, land subsidence, and declining water quality. The overexploitation of the aquifers, exacerbated by extensive irrigation and inefficient water management, has resulted in critical groundwater shortages and widespread subsidence, particularly in the Larissa–Karla and Titarisios Cone systems. Additionally, recent extreme weather events, including Medicane Daniel (2023) and Medicane Ianos (2020), have highlighted the region’s vulnerability to hydrological hazards, with extensive flooding affecting urban and agricultural areas. The re-emergence of Lake Karla as a flood retention area underscores the unintended consequences of past drainage efforts. Remote sensing, geodetic surveys, and historical records have been examined to assess the interplay between groundwater withdrawals, land subsidence, and flood risks. Full article

Water planning and governance strategies must adapt to challenges associated with population growth, climate change, and projected water shortages. In the Western United States, agriculture is the dominant water use, and agricultural water users are being asked to conserve or share their water with other uses. Managing scarce water supplies at the local level often involves creative solutions, many of which are not well documented, especially in the agricultural sector. It is therefore critical to understand ideas to manage scarce water resources from the perspective of agricultural water users and those who work with them. In our research, we used interviews to explore how agricultural water users are managing increasing water scarcity in the Middle Rio Grande basin of central New Mexico and what enables or prevents them from taking innovative action to manage water scarcity. We hypothesized that we would find undocumented water use innovations born out of water users’ responses to lower and more variable water availability in recent years. We primarily recruited interviewees through snowball sampling, with a total of 42 (47%) agricultural water users, decision makers, and non-profit leaders influencing agricultural water governance in the basin accepting our invitation to participate. Our approximately one-hour, semi-structured and open-ended interviews explored agricultural water users’ lived experiences with water governance and opportunities to manage water scarcity. The interviews were recorded, transcribed, coded, and analyzed using HyperRESEARCH software (version 4.5.4). Our results did not support our hypothesis. Instead, we found that agricultural water users struggled to implement well-known innovations amid the pressures of water scarcity, supply uncertainty, administrative complexity, and constraints on their time, labor, and money. Water users and decision makers were mutually interested in implementing innovations in crop choice, flexibility in water storage, use, and management, stricter enforcement of water use efficiency, and access to more efficient irrigation equipment. However, high costs, a lack of knowledge, education, and training, and challenges related to water distribution and scheduling prevented agricultural water users from accessing these and other innovations. Recommendations include incentive-based policies to promote agricultural water use innovations that require high initial costs, improved water accounting at the basin and regional levels to promote flexible and reliable access to agricultural water, targeted education and outreach programming on alternative irrigation methods and cropping patterns, and improved access to irrigation scheduling information to support agricultural water users in planning for water scarcity. Full article

Domestic sewage pollution poses significant risks to human health and the ecological environment but sewage water is gradually recognized as a renewable water resource worldwide. To enhance water resource utilization and facilitate reclamation from domestic sewage, substantial global efforts have focused on developing systematic management strategies and advanced technologies for treatment and resource recovery. This study examines and presents the case of domestic sewage reclamation and water reuse in the rural Hangjiahu region, situated on the southern bank of Taihu Lake in Northern Zhejiang Province, Eastern China. It provides a comprehensive overview of state-of-the-art technologies implemented in the region. In rural areas, sewage treatment is decentralized and involves two primary streams: one where urine is separately disinfected and sterilized, with feces processed into agricultural fertilizer; and another where greywater undergoes bio-composting and wetland treatment to produce recycled water. Additionally, natural rainwater is collected and stored in ponds, enhancing the region’s water resources. The results demonstrate that the integration of domestic sewage reclamation and rainwater storage has effectively mitigated the risks of flooding during rainy seasons and water shortages during droughts. Remarkably, no severe floods or droughts have occurred in the region since 1991, contrasting with historical records from 1909 to 1954, when such events were frequent. This study underscores the potential for replicating these approaches in other regions facing similar challenges. Full article

Yap diatoms—from freshwater streams through estuaries and mangroves to the marine coral reefs—had been sampled in 1988 and 2014 and a few species from the 1988 collections described in a 2009 report. The present paper documents 168 new records, including seven new species, mostly from coral reef habitats, but including some interesting new species from mangroves, and incorporates records published in taxonomic papers. In addition, 44 Mastogloia records were published separately, bringing the taxon total to 245. In the present paper, 32 records are new for Micronesia, while many others are species described from neighboring Guam in the past 15 years. The total represents probably less than one-quarter of the species present on the reef because many specimens of Navicula, Nitzschia, Amphora, etc., have so far been identified only to genus. Floristic studies of benthic diatoms are limited partly by the shortage of taxonomic studies, and we present the taxa for which we can make reasonable arguments for identification, supporting light microscopy with scanning electron micrographs whenever possible. New taxa include Ehrenbergiopsis gen. nov. for Ehrenbergiulva hauckii; Biddulphiella cuniculopsis sp. nov.; Campylodiscus tatreauae sp. nov.; Cymatoneis belauensis from Palau and Cymatoneis yapensis from Yap; Diploneis denticulata sp. nov.; Entomoneis yudinii sp. nov.; and Nitzschia pseudohybridopsis sp. nov. Interesting new records include: Achnanthes cf. brevipes; Actinocyclus decussatus; Caloneis ophiocephala; Licmophora cf. hastata; Lyrella cf. rudiformis; and an unidentified cymatosiroid. One sediment sample included the remains of a planktonic community with Chaetoceros peruvianus, Skeletonema grevillei, Thalassiothrix gibberula and two species of Lioloma, rarely seen in the oligotrophic waters of Micronesia. Full article

The increasing scarcity of water and soil resources, combined with inefficient water and fertilizer management, poses significant challenges to agriculture in arid regions. This study aimed to determine an optimal water and nitrogen regulation model to alleviate water shortages and improve agricultural productivity and quality. In this study, a two-year experiment was conducted to investigate the effects of varying irrigation and nitrogen levels on the soil environment and crop growth in a Lycium barbarum||alfalfa system (LB||AS). The experiment involved four moisture gradients and four nitrogen application levels (using urea as the nitrogen source). The results indicated that soil moisture decreased during crop development, followed by a slow increase, with significant variation across soil depths. Soil temperature peaked during the fruiting stage of Lycium barbarum in July, decreasing significantly with soil depth. Higher temperatures were recorded in N0 under the same irrigation level and in W3 under the same nitrogen level. Soil organic carbon (SOC) levels increased by 16.24% in W3N0 and by 18.05% in W2N1, compared to W0N3. Easily oxidizable organic carbon (EOC) and soluble organic carbon (DOC) levels exhibited significant variations depending on irrigation and nitrogen treatments. Irrigation and nitrogen had a stronger individual impact on alfalfa height and stem thickness than their combined effects. Water and nitrogen regulation significantly influenced Lycium barbarum yield, its 100-fruit weight, and economic efficiency (p < 0.05). The W0N2 treatment produced the highest yield (3238 kg·ha⁻¹), exceeding other treatments by up to 29.52%. In conclusion, the optimal water–nitrogen regulation model for the LB||AS system is full irrigation (75–85% θ_fc) with a nitrogen application rate of 300 kg·ha⁻¹. These findings offer critical insights for improving water and nitrogen management strategies in arid regions. Full article

In the last decades, climate change has led to increasingly frequent drought events within the Mediterranean area, creating an urgent need of a more sustainable management of groundwater resources exploited for drinking and agricultural purposes. One of the most challenging issues is to provide reliable simulations and forecasts of karst spring discharges, whose reduced information, as well as the hydrological processes involving their feeding aquifers, is often a big issue for water service managers and researchers. In order to plan a sustainable water resource exploitation that could face future shortages, the groundwater availability should be assessed by continuously monitoring spring discharge during the hydrological year, using collected data to better understand the past behaviour and, possibly, forecast the future one in case of severe droughts. The aim of this paper is to understand the factors that govern different spring discharge patterns according to rainfall inputs and to present a model, based on artificial neural network (ANN) data training and cross-correlation analyses, to evaluate the discharge of some karst spring in the Umbria region (Central Italy). The model used is a fully connected neural network (FCNN) and has been used both for filling gaps in the spring discharge time series and for simulating the response of six springs to rainfall seasonal patterns from a 20-year continuous daily record, collected and provided by the Regional Environmental Protection Agency (ARPA) of the Umbria region. Full article

In general, decision makers in irrigation systems prioritize the cultivation of diverse crops to ensure sufficient food supply and maximize economic profit, while overlooking ecological resilience. This study proposes a novel reliable multi-objective framework designed to minimize disparities in water distribution between multi-crops, thereby addressing conflicts related to irrigation timing and distribution space. To assess the feasibility of the proposed model, a reliability evaluation technique is employed to examine the conflict ratio of the water distribution policy corresponding to constraints concerning the available water and the water allocated to various crops ($C\text{-}value$). Next, to evaluate the reliable optimal multi-objective model, we examined the disparity of water distribution among four crops—fodder, watermelon, wheat, and grape—cultivated in three sub-areas of the Zayandehroud watershed, a watershed experiencing water shortage in the center of the Iranian plateau. Subsequently, given the overlooking of water conservation policies, this study investigates the impact of alternative perspectives on the disparity of water distribution and the conflict domain. The final results indicate that grapes exhibit lower sensitivity to water consumption, whereas watermelon is the most sensitive. In terms of the conflict domain, the city of Lenjanat recorded the least sensitivity. Full article

In recent decades, the main commercial crops of Mato Grosso, such as soybeans, corn, and cotton, have been undergoing transformations regarding the adoption of new technologies to increase production. However, regardless of the technological level, the climate of the region, including the rainfall regime, can influence the success of crops and facilitate, or not, the maximum production efficiency. This study aimed to define the behavior of the variability in monthly and annual rainfall and its probability of monthly occurrence and calculate the drought index for the northwestern region of Mato Grosso, in the southern region of the Brazilian Amazon. To carry out the study, daily rainfall records were collected, calculating the totals for each month of the historical series for each of the four National Water and Sanitation Agency (ANA) rain gauge stations, Aripuanã (1985–2020), Colniza (2001–2020), Cotriguaçu (2004–2020), and Juína (1985–2020), representing the northwestern region. The annual distribution of rainfall during the periods studied ranged from 1376.2 to 3017.3 mm. The monthly distribution indicated a typical water shortage in the months of June, July, and August. The probability of rainfall near the average for each month was more than 50%. The monthly SPI-1 index revealed a total of 56 months affected by very dry events and 34 extreme dry events. The annual SPI-12 index pointed to seven very dry years and five extremely dry years. Therefore, the region presented high rainfall rates in most years; however, a significant process of drought was also observed, including in rainy months, which are the periods with the greatest demand for the main agricultural crops. Full article

The current global scenario of unequal access to water and electricity motivates the search for solutions based on available resources, such as renewable energies and desalination. Additionally, adequate sizing of renewables requires extensive and reliable time series, which are usually unavailable. Reanalysis models are an option to consider, but only after evaluating their local accuracy, generally through performance metrics. This study evaluated the performance of the solar radiation, temperature, and wind speed products from MERRA2 and ERA5-Land in comparison to ground data, as well as their influence on the optimal initial configuration of a renewable energy system for desalination in La Guajira, Colombia. HOMER Pro was the software tool employed to establish the best arrangements for the resulting renewable power systems, and the study included a sensitivity analysis considering different annual capacity shortages, operating hours, and energy needs for desalting. ERA5-Land performed better than MERRA2 in matching the time series from the local station. The relative error of the cost of electricity of systems dimensioned from reanalysis was less than 3% compared to systems from ground measurements, with a renewable fraction above 98%. For the study area, ERA5-Land reanalysis represents a reliable alternative to address the scarcity of solar resource records, but both reanalyses failed to reproduce the wind speed regime. Full article

Arid regions are susceptible to flash floods and severe drought periods, therefore there is a need for accurate and gap-free rainfall data for the design of flood mitigation measures and water resource management. Nevertheless, arid regions may suffer from a shortage of precipitation gauge data, whether due to improper gauge coverage or gaps in the recorded data. Several alternatives are available to compensate for deficiencies in terrestrial rain gauge records, such as satellite data or utilizing geostatistical interpolation. However, adequate assessment of these alternatives is mandatory to avoid the dramatic effect of using improper data in the design of flood protection works and water resource management. The current study covers 75% of the Kingdom of Saudi Arabia’s area and spans the period from 1967 to 2014. Seven satellite precipitation datasets with daily, 3-h, and 30-min temporal resolutions, along with 43 geostatistical interpolation techniques, are evaluated as supplementary data to address the gaps in terrestrial gauge records. The Normalized Root Mean Square Error by the mean value of observation (NRMSE) is selected as a ranking criterion for the evaluated datasets. The geostatistical techniques outperformed the satellite datasets with 0.69 and 0.8 NRMSE for the maximum and total annual records, respectively. The best performance was found in the areas with the highest gauge density. PERSIANN-CDR and GPM IMERG V7 satellite datasets performed better than other satellite datasets, with 0.8 and 0.82 NRMSE for the maximum and total annual records, respectively. The spatial distributions of maximum and total annual precipitation for every year from 1967 to 2014 are generated using geostatistical techniques. Eight Probability Density Functions (PDFs) belonging to the Gamma, Normal, and Extreme Value families are assessed to fit the gap-filled datasets. The PDFs are ranked according to the Chi-square test results and Akaike information criterion (AIC). The Gamma, Extreme Value, and Normal distribution families had the best fitting over 56%, 34%, and 10% of the study area gridded data, respectively. Finally, the selected PDF at each grid point is utilized to generate the maximum annual precipitation for 2, 5, 10, 25, 50, and 100-year rasters that can be used directly as a gridded precipitation input for hydrological studies. Full article

In the realm of agriculture, biodegradable films are emerging as a promising substitute for traditional polyethylene (PE) films. Despite their potential, there has been a notable lack of extensive research on their effectiveness in the context of dry direct-seeded rice cultivation. Addressing this gap, a comprehensive biennial study was conducted in the northeastern regions of China, focusing on the ‘Baonong 5’ rice variety. This study meticulously compared three distinct cultivation methods: (1) employing biodegradable film mulching, (2) using conventional plastic film mulching, and (3) cultivating without any mulch. The findings revealed that biodegradable film mulching significantly enhanced soil moisture control, increased leaf area, and improved rice yield and water utilization efficiency (p < 0.05) compared to the plots without mulch. Notably, there was no marked difference in outcomes between the plastic film mulching and the unmulched plots. This research underscores the profound benefits of biodegradable film in rice cultivation, particularly from an environmental sustainability perspective. This innovative method not only boosts agricultural productivity but also addresses critical environmental challenges like climate change and water conservation. The application of biodegradable mulch has proven to be remarkably effective in improving irrigation efficiency and crop water conservation, leading to enhanced rice development and higher yields. The study recorded a substantial increase in water productivity—30% in 2021 and between 52.85% and 60% in 2022—compared to traditional cultivation practices. Furthermore, the use of biodegradable mulch resulted in significantly higher rice yields than the non-mulched plots, thus contributing to increased profitability. Such methods not only yield higher crop outputs but also mitigate environmental issues like water pollution and help alleviate prevalent water shortages in rice farming. Full article