Improved Water Balance Research Articles

Quantitative Analysis about the Spatial Heterogeneity of Water Conservation Services Function Using a Space–Time Cube Constructed Based on Ecosystem and Soil Types

Precisely delineating the spatiotemporal heterogeneity of water conservation services function (WCF) holds paramount importance for watershed management. However, the existing assessment techniques exhibit common limitations, such as utilizing only multi-year average values for spatial changes and relying solely on the spatial average values for temporal changes. Moreover, traditional research does not encompass all WCF values at each time step and spatial grid, hindering quantitative analysis of spatial heterogeneity in WCF. This study addresses these limitations by utilizing an improved water balance model based on ecosystem type and soil type (ESM-WBM) and employing the EFAST and Sobol’ method for parameter sensitivity analysis. Furthermore, a space–time cube of WCF, constructed using remote-sensing data, is further explored by Emerging Hot Spot Analysis for the expression of WCF spatial heterogeneity. Additionally, this study investigates the impact of two core parameters: neighborhood distance and spatial relationship conceptualization type. The results reveal that (1) the ESM-WBM model demonstrates high sensitivity toward ecosystem types and soil data, facilitating the accurate assessment of the impacts of ecosystem and soil pattern alterations on WCF; (2) the EHSA categorizes WCF into 17 patterns, which in turn allows for adjustments to ecological compensation policies in related areas based on each pattern; and (3) neighborhood distance and the type of spatial relationships conceptualization significantly impacts the results of EHSA. In conclusion, this study offers references for analyzing the spatial heterogeneity of WCF, providing a theoretical foundation for regional water resource management and ecological restoration policies with tailored strategies.

Quantitative performance analysis of anion-exchange membrane fuel cells with in-plane and through-plane water transport

Effective water management is crucial in anion-exchange membrane fuel cells (AEMFCs) due to water's dual role as a reactant during alkaline oxygen reduction and a product of alkaline hydroxide oxidation. Meanwhile, both hydroxide conduction and water transport in polymer electrolytes are highly dependent on the hydration level. Therefore, a three-dimensional multi-physics model is developed to investigate the critical role of ionic and water transport parameters of the electrolyte on AEMFC performance. Additionally, detailed water distribution analysis is used to reveal its fundamental mechanism. The results reveal that extremely inhomogeneous water distribution and cathode water starvation are the main causes of the poor cell performance. Moreover, increasing membrane water diffusivity, water conversion, and decreasing the electro-osmotic drag coefficient all contribute to better cell performance through improved water balance and cathode water supply. Among these, cell performance is most sensitive to membrane water diffusivity, with a 40 % increase in peak power density when it is increased from 10−10 m2 s−1 to 10−9 m2 s−1. Although high ionic conductivity improves cell performance by directly reducing ohmic impedance, it also results in a more inhomogeneous distribution of water in the whole cell, so that a four-fold increase in ionic conductivity only yields a 62 % increase in peak power density.

Populus euphratica CPK21 Interacts with NF-YC3 to Enhance Cadmium Tolerance in Arabidopsis.

The toxic metal cadmium (Cd) poses a serious threat to plant growth and human health. Populus euphratica calcium-dependent protein kinase 21 (CPK21) has previously been shown to attenuate Cd toxicity by reducing Cd accumulation, enhancing antioxidant defense and improving water balance in transgenic Arabidopsis. Here, we confirmed a protein-protein interaction between PeCPK21 and Arabidopsis nuclear transcription factor YC3 (AtNF-YC3) by yeast two-hybrid and bimolecular fluorescence complementation assays. AtNF-YC3 was induced by Cd and strongly expressed in PeCPK21-overexpressed plants. Overexpression of AtNF-YC3 in Arabidopsis reduced the Cd inhibition of root length, fresh weight and membrane stability under Cd stress conditions (100 µM, 7 d), suggesting that AtNF-YC3 appears to contribute to the improvement of Cd stress tolerance. AtNF-YC3 improved Cd tolerance by limiting Cd uptake and accumulation, activating antioxidant enzymes and reducing hydrogen peroxide (H2O2) production under Cd stress. We conclude that PeCPK21 interacts with AtNF-YC3 to limit Cd accumulation and enhance the reactive oxygen species (ROS) scavenging system and thereby positively regulate plant adaptation to Cd environments. This study highlights the interaction between PeCPK21 and AtNF-YC3 under Cd stress conditions, which can be utilized to improve Cd tolerance in higher plants.

Clinical Effect of the Traditional Japanese Herbal Medicine "Goreisan" on Water Balance in Patients With Severe Acute Pancreatitis.

Since severe acute pancreatitis (SAP) involves inflammatory mediators produced by local inflammation of the pancreas that trigger a systemic inflammatory response, intensive fluid management is required to maintain hemodynamics in the early stages of the onset of SAP. Goreisan is considered to have a diuretic effect in a state of excess water and an antidiuretic effect in a state of dehydration, regulating water balance in both directions. We investigated the clinical effects of Goreisan on water balance in SAP patients. Patients and methods: SAP patients admitted to our ICU within 72 hours of being diagnosed with SAP were divided into two groups: the Rikkunshito group (before October 2015) and theGoreisan group (after November 2015). Cumulative volume of fluid infusion, urine, fluid removal by CHF, nasogastric tube drainage, and water balance from day 1 to day 5 of ICU admission. Thirty patients were included. The median age was 57 (40-69) years, and 21/30 (70%) were male. The prognostic factor score in Japanese criteria for acute pancreatitis was 5.5 (3.3-7). Of the thirty patients, 14 were in the Rikkunshito group, and 16 were in the Goreisan group. There were no differences in the cumulative volume of fluid infusion, urine, fluid removal by CHF, or nasogastric tube drainage from day 1 to day 5 of ICU admission between the two groups. However, the cumulative water balance from day 1 to day 5 of admission was 4,957 ± 6,091 mL in the Rikkunshito group, whereas it was lower in the Goreisan group at 498 ± 3,918 mL (P = 0.023). Our study showed that Goreisan administration in patients with severe acute pancreatitis might improve water balance in the early phase of onset. Early administration of Goreisan at the onset of severe acute pancreatitis may regulate fluid movement between capillaries and interstitium and alleviate fluid overload due to water refill.

REGIONAL MANIFESTATIONS OF THE DETERIORATION OF THE NATURAL CONDITIONS OF HEAT AND MOISTURE SUPPLY OF THE TERRITORY IN THE CONDITIONS OF MAINTAINING THE SUSTAINABLE FUNCTIONING OF ECONOMY SYSTEMS IN THE TERRITORY OF TERNOPIL REGION

The publication examines the influence of regional manifestations of the deterioration of natural conditions (moisture supply and unfavorable thermal parameters) on agricultural management. Global climate changes are superimposed by regional manifestations of adverse processes, such as the emission of greenhouse gases generated by an unbalanced land structure, in which we observe an excessive share of arable land. Excessive plowing of the territory leads to increased production of greenhouse gases by arable land, which complicates the manifestation of the greenhouse effect at the local level. Data on the structure of land plots of Ternopil region and Borsukiv territorial community are given. Attention is drawn to the map scheme of changes in the moisture supply of the territory of Ukraine, according to which a very wet climatic annual balance will be preserved only in the mountainous part of the Carpathians, Ternopil region will go from wet to insufficiently wet in its southeastern part, and over time, according to the forecast of 2100, to an insufficiently wet balance in the greater its territory At the same time, about 55% of the southeastern regions are threatened by dry and very dry climatic annual balance. According to the authors, the search for ways to solve the problem can be found in the optimization of land use. The algorithm of the optimization model is prescribed in the methodology of Professor Mykhailo Grodzynskii and consists in determining and ranking the development priorities of the research area and achieving a scientifically justified ratio between natural and anthropogenic land areas. Based on the materials of the Borsukiv territorial community, an optimization model of land use was created, according to which it is proposed to reduce the share of arable land from 65% to 45% due to the removal of heavily eroded and poorly productive lands from the arable wedge and their transfer to liming and afforestation, the share of which in the land use structure of the territorial community increased respectively 21% and 23%. Such optimization measures will ensure the transition from the emission of greenhouse gases by land to their assimilation by forest and meadow vegetation. Increasing the share of forests by 14% will contribute to a 5% increase in precipitation of local origin, which is especially important for stabilizing the water balance of the territory. An increase in the share of natural vegetation will contribute to the maintenance of ecological balance, restoration of biotic and landscape diversity, improved water balance, and natural living conditions of the population.Increasing or stabilizing the degree of humidification of territories under the conditions of global and regional climate changes is becoming an important scientific and applied problem, the solution of which requires the development and implementation of strategic tasks of sustainable development at the levels of regional, administrative and district territorial entities, the level of territorial communities, Starosty districts. Taking into account the priority criteria for the development of territorial entities is the first stage of optimizing the use of nature in these administrative-territorial entities. The second stage of the landscape and ecological optimization of territories is the substantiation of the ratio of natural and anthropogenic lands. Land optimization will contribute to tireless use of nature and the balancing of basic natural processes with anthropogenic ones. In the future, we envisage the creation of optimization models of land use for all territorial communities of the region, which will optimize the development of natural and economic systems. Keywords: regional manifestations of climatic conditions, land use structure, optimization, territorial community.

Foliar spraying of zinc oxide nanoparticles improves water transport and nitrogen metabolism in tomato (Solanum lycopersicum L.) seedlings mitigating the negative impacts of cadmium.

The use of bio-nanotechnology in agriculture-such as the biological applications of metal oxide nanoparticles (NPs)-greatly improves crop yield and quality under different abiotic stress factors including soil metal contamination. Here, we explore the effectiveness of zinc oxide (ZnO)-NPs (0, 50 mg/L) foliar spraying to ameliorate the detrimental effects of cadmium (Cd) on the water transport and nitrogen metabolism in tomato (Solanum lycopersicum Mill. cv. Chibli F1) plants grown on a Cd-supplied (CdCl2; 0, 10, 40 μM) Hoagland nutrient solution. The results depicted that the individually studied factors (ZnO-NPs and Cd) had a significant impact on all the physiological parameters analyzed. Independently to the Cd concentration, ZnO-NPs-sprayed plants showed significantly higher dry weight (DW) in both leaves and roots compared to the non-sprayed ones, which was in consonance with higher and lower levels of Zn2+ and Cd2+ ions, respectively, in these organs. Interestingly, ZnO-NPs spraying improved water status in all Cd-treated plants as evidenced by the increase in root hydraulic conductance (L0), apoplastic water pathway percentage, and leaf and root relative water content (RWC), compared to the non-sprayed plants. This improved water balance was associated with a significant accumulation of osmoprotectant osmolytes, such as proline and soluble sugars in the plant organs, reducing electrolyte leakage (EL), and osmotic potential (ψπ). Also, ZnO-NPs spraying significantly improved NO3- and NH4+ assimilation in the leaf and root tissues of all Cd-treated plants, leading to a reduction in NH4+ toxicity. Our findings point out new insights into how ZnO-NPs affect water transport and nitrogen metabolism in Cd-stressed plants and support their use to improve crop resilience against Cd-contaminated soils.

Research on land subsidence-rebound affected by dualistic water cycle driven by climate change and human activities in Dezhou City, China

Over-exploitation of groundwater is the principal anthropogenic trigger for land subsidence in the North China Plain (NCP). With the promulgation of policies on groundwater extraction restrictions and bans, seasonal fluctuations and uplift have begun to occur in some typical subsidence areas in the NCP. In order to explore the land subsidence-rebound drivers, this study takes Dezhou City, a typical subsidence area in the NCP, as the study area and selects the main drivers in climate change: precipitation and evapotranspiration and the main driver in human activities: groundwater extraction, which together forms the background of the regional dualistic water cycle. In this background, this study selects the corresponding datasets and uses the improved Water Balance constraints Recurrent Neural Network (WB-RNN) method to establish the link between precipitation data, evapotranspiration data, groundwater extraction and groundwater level. Then uses the Gate Recurrent Unit-Convolutional Neural Network (GRU-CNN) method to establish the link between groundwater level and Interferometric Synthetic Aperture Radar (InSAR) deformation, and then obtains the link between the drivers of the dualistic water cycle and land subsidence. Comparative analysis and changing model inputs found that 1) Seasonal fluctuations in land subsidence-rebound in Dezhou City are mainly controlled by the groundwater levels in Aquifer Groups III and IV, with amplitudes up to 15 mm per year. 2) Groundwater level changes in different layers lag precipitation at different times. Excluding the influence of human extraction factors, the maximum ground surface deformation fluctuation caused by monthly 260 mm precipitation can be up to 21.44 mm. 3) The impact of short-term heavy precipitation caused by Typhoon Lekima and Doksuri in 2019 and 2023 can cause deformation fluctuations to a certain extent.

Nano Silver and melatonin effectively delay the senescence of cut carnation flowers under simulated vibrational stress

ABSTRACT Carnation (Dianthus caryophyllus L.) holds great significance as a cut flower, and its vase life plays a crucial role in determining its quality and market appeal. However, the extended transportation distances from the production location to consumer markets can have an unfavourable impact on the vase life and overall quality of cut flowers. The first experiment demonstrated that exposing cut carnation flowers to simulated vibrational stress (SVS) led to a decline in vase life and overall quality. Notably, the application of Nano Silver (NS; 25 and 50 μM) and melatonin (MT; 100 and 200 μM) into the holding solution proved effective in counteracting these negative effects, and extended the vase life by promoting cut flower water relations. In the second experiment, the optimal concentrations of NS and MT into the holding solution (25 and 100 μM, respectively) effectively reduced chlorophyll degradation, electrolyte leakage, and lipid peroxidation by enhancing the activity of catalase and peroxidase enzymes. As a result, it appears that the application of NS and MT in the holding solution has successfully prolonged vase life by both improving water balance and boosting antioxidant activity, while mitigating the negative effects of SVS.

Melatonin enhances vase life and alters physiological responses in peony (Paeonia lactiflora Pall.) cut flowers

The postharvest response of two peony cultivars, 'Qi Hua Lu Shuang' and 'Da Fu Gui', to exogenous treatment with three concentrations (25, 50, and 75 μmol·L−1) of melatonin (MT) was evaluated. Both cultivars demonstrated a similar response to MT treatment in terms of delayed senescence, albeit with differing efficacies. The optimal concentration of MT (50 μmol·L−1) extended the vase life of 'Qi Hua Lu Shuang' and 'Da Fu Gui' by 1.6 and 1.2 days, respectively, relative to the control. This treatment also increased maximum flower diameter by 11.76% and 21.26%, respectively, and improved water balance, with 'Qi Hua Lu Shuang' maintaining stability for 6.0 days and 'Da Fu Gui' for 5.7 days longer than the control. Relative electrical conductivity and malondialdehyde (MDA) content, when treated with 50 μmol·L−1 MT, were reduced by 25.25% and 18.03% for 'Qi Hua Lu Shuang', and by 33.96% and 21.47% for 'Da Fu Gui', respectively. At this MT concentration, soluble sugar content peaked at 6.91 mg·g−1 FW for 'Qi Hua Lu Shuang' and 8.12 mg·g−1 FW for 'Da Fu Gui', while soluble protein content reached 5.07 mg·g−1 FW and 7.93 mg·g−1 FW, respectively. Additionally, at the same concentration of MT, the activities of antioxidant enzymes activities (SOD and CAT) were significantly enhanced. SOD activity peaked at 749.61 U·g−1 FW in 'Qi Hua Lu Shuang' and at 652.77 U·g−1 FW in 'Da Fu Gui', while CAT activity showed increases of 31.86% in 'Qi Hua Lu Shuang' and 44.46% in 'Da Fu Gui', compared to the control. These results demonstrate that 50 μmol·L−1 MT optimally delays senescence and preserves the postharvest quality of cut peonies, offering valuable insight for the floral industry.

Evaluation of Water Balance and Water Use Efficiency with the Development of Water-Saving Irrigation in the Yanqi Basin Irrigation District of China

Irrigation water is the main type of water consumption in the Yanqi Basin irrigation district of Xinjiang, which is an oasis-type irrigation district in the arid region of Northwest China. With the continuous expansion of cultivated areas, there is an increasing demand for irrigation water, resulting in an irrigation efficiency paradox and the phenomenon of “the more water-saving, the more water-scarce”. In this study, the water balance method and the improved IWMI (International Water Management Institute) water balance method were used with remote sensing and statistical data from 1980 to 2020 to analyze the changes in the irrigation water supply, consumption, and loss for improvement in irrigation water use efficiency (IWUE) in the Yanqi Basin. The results showed that there was an upward trend in the cultivated land area in the irrigation district of Yanqi Basin, as monitored with remote sensing from 1980 to 2020, and the values from the remote sensing data were higher than those from the yearbooks. According to the remote sensing data, the arable land area in the irrigation district increased from 1672 km2 in 1980 to 2494 km2 in 2020, thus showing a trend of expansion. The traditional water use efficiency in the irrigation district showed an increasing trend. The lowest value for the field water-use coefficient was 0.70 in 1998, and it exceeded to 0.81 from 2009 to 2020. The canal water-use coefficient was as low as 0.50 in 1998 and increased from 0.54 in 2009 to 0.82 in 2020. The irrigation water-use coefficient increased from 0.35 in 1998 to 0.68 in 2020, with a general upward trend. In this study, the water consumption ratio indicator DFg (depleted fraction), determined using the improved water balance method, increased from 0.8390 in 1980 to 0.8562 in 2020, although it showed an overall decreasing trend, and the average was 0.8436. Cultivated land’s actual irrigation water consumption per unit area reached the highest value of 8.41 × 106 m3/hm2/a in 2011 and the minimum value of 4.01 × 106 m3/hm2/a in 2020, and from 1980 to 2020 it showed a decreasing trend, while the total water diversion showed an increasing trend due to the continuous expansion of arable land. From 1980 to 2020, water diversion into the irrigation district changed from 1.214 km3 to 1.000 km3, and it reached a maximum of 1.593 km3 in 2000; water diversion into the irrigation district showed an overall upward trend. The positive impact of the post-2000 water conservation phase with the adaptation of water-saving irrigation technology was clear, as the findings showed an increase in IWUE in the Yanqi Basin irrigation district. These results provide a theoretical basis for breaking the paradox of irrigation efficiency, which can be used in the water resource management of irrigation districts.

Evaluation of Baseflow Modeling with BlueM.Sim for Long-Term Hydrological Studies in the German Low Mountain Range of Hesse, Germany

So far, research with the hydrological model BlueM.Sim has been focused on reservoir management and integrated river basin modeling. BlueM.Sim is part of the official toolset for estimating immissions into rivers in Hesse (Germany) via long-term continuous modeling. Dynamic runoff modeling from rural catchments is permitted within the Hessian guidelines, but in practice, a constant flow or low flow is used. However, due to increasing water stress in the region caused by climate change, the dynamic modeling of runoff from rural catchments will become necessary. Therefore, dynamic baseflow modeling with BlueM.Sim is of the greatest importance. This study evaluated baseflow modeling with BlueM.Sim in a representative hard-rock aquifer in the German Low Mountain range. Two model setups (Factor Approach (FA): CN method + monthly baseflow; Soil Moisture Approach (SMA): physical soil moisture simulation) were calibrated (validated) for a 9-year (5-year) period. The FA achieved an NSE of 0.62 (0.44) and an LnNSE of 0.64 (0.60) for the calibration and validation periods. The selection of a solution for the successful validation of the FA was challenging and required a selection that overestimated baseflow in the calibration period. This is due to the major disadvantage of the FA, namely, that baseflow can only vary according to an estimated yearly pattern of monthly baseflow factors. However, the data requirements are low, and the estimation of monthly baseflow factors is simple and could potentially be regionalized for Hesse, leading to a better representation of baseflow than in current practice. The SMA achieved better results with an NSE of 0.78 (0.75) and an LnNSE of 0.72 (0.78). The data requirements and model setup are extensive and require the estimation of many parameters, which are limitations to its application in practice. Furthermore, a literature review has shown that a single linear reservoir, as in BlueM.Sim, is not optimal for modeling baseflow in hard-rock aquifers. However, for detailed climate change impact studies in the region with BlueM.Sim, the SMA should be preferred over the FA. It is expected that BlueM.Sim would benefit from implementing a more suitable model structure for baseflow in hard-rock aquifers, resulting in improved water balance and water quality outcomes.

Extreme environments as sources of fungal endophytes mitigating climate change impacts on crops in Mediterranean‐type ecosystems

Societal Impact StatementClimate change is predicted to increase drought and soil salinity in Mediterranean‐type ecosystems (MTEs), posing a significant threat to global food security. Genetic modification of crops to counteract this threat is expensive and has not met with universal support, and alternatives are hence needed to enhance crop production in MTEs. Here, fungal endophytes from the Atacama Desert, High Andes and Antarctica inoculated onto three crops were found to alleviate the negative effects of drought and salinity on plant performance. The study concludes that extremophile endophytes might be used to enhance crop performance as the climate of MTEs changes over future decades.Summary Climate change will curtail the ability to provide sufficient food for our rapidly expanding population. Improvements to crop production in changing environments, particularly Mediterranean‐type ecosystems (MTEs), which are increasingly subjected to drought and salinisation, are hence urgently needed. Here, we explored the possibility that fungal endophytes from extreme environments can be used to enhance crop yield, survival and tolerance to environmental stresses. Plants of lettuce, tomato and bell pepper were inoculated with up to six species of endophytic fungi isolated from the Atacama Desert, the High Andes and Antarctica. They were then exposed in the field for up to 120 days in each of three summers to current climatic conditions or to a future climate scenario simulating increased drought and soil salinisation. Compared with uninoculated plants, the yield and survival of inoculated crops were increased by up to two‐fold under the future climate scenario. These effects were in part attributable to the improved water balance of inoculated crops exposed to drought and salinisation. The inocula also increased the concentrations of total phenols and proline in leaves and decreased lipid peroxidation when plants were subjected to increased aridity and salinity. A mixed inoculum of six endophytes from the extreme environments conferred the most beneficial effects on crop performance, with a commercially available inoculum having fewer positive effects on crops. We conclude that the inoculation of crops with endophytes from extreme environments may be a viable solution to sustaining crop production in MTEs exposed to rapid climate change.

Integration of the generalized complementary relationship into a lumped hydrological model for improving water balance partitioning: A case study with the Xinanjiang model

Lumped hydrological models (LHMs) are useful tools for simulating catchment runoff (Q) owing to their low data requirements, high computational efficiency, and robust performance. However, most LHMs are purposely conceptualized for rainfall-runoff modeling with over-simplified consideration of other water balance components, especially evapotranspiration (E). The generalized complementary relationship (GCR) can reliably estimate the regional E using only routine meteorological observations. Here, a lumped hydrological model (Xinanjiang model, XAJ) was integrated with the GCR (XAJ-GCR) to improve the accuracy of the water balance partitioning of LHMs. Long-term daily observations of Q and E in the Seolmacheon experimental watershed (8.54 km2) in South Korea were collected to test the capability of the XAJ-GCR model to capture Q and E dynamics with three different integration schemes and three different calibration strategies (single or multi-objective). Results show that XAJ-GCR model obtained excellent results in simulating Q (NSEQ = 0.91 ± 0.02) and markedly improves simulating E with NSEE from − 0.35 ± 0.27 (mean ± standard deviation) to 0.56 ± 0.10. The multi-objective calibration strategy achieves better simulation results for Q and E simultaneously with NSEQ = 0.93 and NSEE = 0.69 ± 0.01, in which the built-in structure of the XAJ model is the optimal scheme. This study demonstrated that the integration of GCR into LHMs is feasible and applicable for improving water balance partitioning. The integration maintains all the advantages of LHM and does not increase the model complexity and data requirements.

Insight into the physiological and biochemical mechanisms of biostimulating effect of Ascophyllum nodosum and Moringa oleifera extracts to minimize cadmium-induced oxidative stress in rice.

Cadmium (Cd) is a serious threat for environmental sustainability as it can be taken up quickly by plants and transported to the food chain of living organisms. It alters plants' metabolic and physiological activities and causes yield loss, thereby, enhancing plant tolerance to Cd stress is of utmost essential. Therefore, an experiment was executed to investigate the potential role of Ascophyllum nodosum extract (ANE) and moringa (Moringa oleifera) leaf extract (MLE) to confer Cd tolerance in rice (Oryza sativa cv. BRRI dhan89). Thirty-five-day-old seedling was subjected to Cd stress (50mgkg-1 CdCl2) alone and in a combination of ANE (0.25%) or MLE (0.5%) in a semi-controlled net house. Exposure to Cd resulted in accelerated production of reactive oxygen species, enhanced lipid peroxidation, and disrupted antioxidant defense and glyoxalase system, thus retarded plant growth, biomass production, and yield attributes of rice. On the contrary, the supplementation of ANE or MLE enhanced the contents of ascorbate and glutathione, and the activities of antioxidant enzymes such as ascorbate peroxidase, dehydroascorbate reductase, monodehydroascorbate reductase, glutathione reductase, glutathione peroxidase, and catalase. Moreover, supplementation of ANE and MLE enhanced the activities of glyoxalase I and glyoxalase II which prevented the overgeneration of methylglyoxal in Cd stressed rice plants. Thus, because of ANE and MLE addition Cd-induced rice plants showed a noticeable declination in membrane lipid peroxidation, hydrogen peroxide generation, and electrolyte leakage, whereas improved water balance. Furthermore, the growth and yield attributes of Cd-affected rice plants were improved with the supplementation of ANE and MLE. All the studied parameters indicates the potential role of ANE and MLE in mitigating Cd stress in rice plants through improving the physiological attributes, modulating antioxidant defense and glyoxalase system.

Seasonal divergence of evapotranspiration sensitivity to vegetation changes – A proportionality-hypothesis-based analytical solution

Seasonal variation of vegetation profoundly affects the water cycle. However, the seasonal divergence of evapotranspiration (ET) sensitivity in response to vegetation variations has not been fully understood. Here we derived an analytical solution to examine the impact of seasonal vegetation changes on ET with an extended Budyko framework based on an improved ET algorithm with improved water balance constraints. Results reveal a clear seasonal divergence of ET sensitivity to vegetation coverage changes across climate regimes and biomes. Generally, the high ET sensitivity to vegetation coverage has a clear north-south shift trajectory from spring to winter. For moderate-humid regions (0.7 < aridity index < 1.0), vegetation exhibits higher importance in altering ET in March-September. While for moderate-dry regions (1.0 < aridity index < 1.4), the sensitivity of ET to vegetation changes is the highest in September-November. Moreover, the spatial-temporal pattern of ET sensitivity to seasonal vegetation changes is different between short vegetation cover and forest. Additionally, negative ET sensitivity to vegetation coverage changes was discovered in regions with seasonal precipitation of less than 500 mm and sparse vegetation coverage (predominant land cover types of grassland, scrubland, and savannas). In summary, our study provides an analytical solution to estimate ET sensitivity to seasonal vegetation changes within the extended Budyko framework. The results highlight the difference in hydrological response to vegetation dynamics across seasons and vegetation types.

Reconstruction of the water cycle process reveals the 600-year evolution of the human-water relationship in Tunpu, China

The human-water relationship (HWR) has shifted from the simple utilization of water resources to a complex spatial redistribution process through powerful human activities, such as water conservancy projects and policies. Water conservancy projects have changed the HWR; however, it is still unclear how related policies, such as the ecological civilization policy recently advocated by the Chinese government, affect the HWR. Here, a nearly 600-year typical Tunpu village named Baojia Tun was taken as the study area. Based on an improved water balance formula and a new technology known as remote sensing hydrological station (RSHS), the water cycle process over nearly 600 years in the typical Tunpu village named Baojia Tun and its basin was reconstructed, and the long-term evolution of the HWR over different space and time spans was revealed. The results show that (1) the HWR developed from an initial resource-rich balanced stage to an extensive-development unbalanced stage and finally transformed into a rebalancing stage; the four stages of the HWR are predevelopment, take-off, acceleration, and rebalancing. (2) At the village scale, due to the suitable geographical conditions and cultural value, the composition of water use units in the water cycle process of Baojia Tun has generally remained stable from the Ming Dynasty to modern times. (3) At the basin scale, due to the increased runoff caused by land use/cover change being more significant than the decreased runoff caused by irrigation water intake, the trend of runoff shifted from slowly decreasing to accelerated increases, with the change rate of runoff increasing from −6.21 × 104 m3·a-1 in the Ming Dynasty (1470–1636) to 48.78 × 104 m3·a-1 in the China stage (1949–2020). (4) The synchronous promotion of socioeconomic development and the ecological civilization policy has realized the unity of socioeconomic and ecological benefits, making the HWR exhibit a good sign of rebalancing. This research reveals that the positive effect of ecological civilization policy on the HWR can eliminate the unfavourable factors in the previous development model and adjust it to a sustainable development model, providing significant enlightenment for long-term planning and policy formulation for sustainable high-quality development in other countries or regions.

Modulation of physiological and biochemical traits of two genotypes of Rosa damascena Mill. by SiO2-NPs under In vitro drought stress

BackgroundDrought is a major abiotic stress that restricts plant growth and efficiency although some nutrients such as silicon improve drought tolerance by regulating the biosynthesis and accumulating some osmolytes. In this regard, a completely randomized factorial design was performed with three factors including two genotypes (‘Maragheh’ and ‘Kashan’), three concentrations of silicon dioxide nanoparticles (SiO2-NPs) (0, 50, and 100 mg L− 1), and five concentrations of PEG (0, 25, 50, 75, and 100 g L− 1) with three replications.ResultsThe findings showed that drought stress decreased protein content and it was improved by SiO2-NPs, so the genotype of ‘Maragheh’ treated with 100 mg L− 1 SiO2-NPs had the highest protein content. Under severe drought stress, had a higher membrane stability index (MSI) than ‘Kashan’, and the ‘Maragheh’ explants subjected to 100 mg L− 1 SiO2-NPs exhibited the uppermost MSI. The explants supplemented with 100 mg L− 1 SiO2-NPs sustained their photosynthetic parameters more in comparison with other treatments under drought stress conditions and as well as 100 mg L− 1 SiO2-NPs showed higher content of protein and proline of ‘Maragheh’ than ‘Kashan’. Drought stress reduced Fm, Fv/Fm, and Fv, while SiO2-NPs treatment enhanced these parameters. SiO2-NPs also improved water deficit tolerance by enhancing the activity of antioxidant enzymes such as catalase (CAT), peroxidase (POD), guaiacol peroxidase (GPX), and superoxide dismutase (SOD) and reducing lipid peroxidation and H2O2 concentration.ConclusionsAccording to the findings, the genotype ‘Maragheh’ was more tolerance to drought stress than ‘Kashan’ by improving water balance, antioxidant enzyme activities, and membrane stability as it was obtained from the unpublished previous evaluation in in vivo conditions and we concluded based on these results, in vitro culture can be used for drought screening in Damask rose plants. The results of the current study revealed that the induced drought stress by polyethylene glycol (PEG) in two Damask rose genotypes was ameliorated with SiO2-NPs and the tolerance genotypes were better than the sensitive ones in response to SiO2-NPs treatment.

Thermal imaging of increment cores: a new method to estimate sapwood depth in trees

The cells in tree sapwood form a network of interconnected conduits which enables the transport of water and nutrients from the tree roots to the canopy. Sapwood depth must be assessed when tree water use is estimated from sap flow velocities. However, current approaches to assess sapwood depth are either not applicable universally, or require expensive instruments, the application of chemicals or laborious field efforts. Here, we present a new method, which estimates sapwood depth by thermal imaging of increment cores. Using a low-cost thermal camera for mobile devices, we show that the sapwood–heartwood boundary is detectable by a sharp increase in temperature. Estimated sapwood depths agree with dye estimates (R2 = 0.84). We tested our approach on a broad range of temperate and tropical tree species: Quercus robur, Pinus sylvestris, Swietenia macrophylla, Guazuma ulmifolia, Hymenaea courbaril, Sideroxylon capiri and Astronium graveolens. In nearly all species, the methods agreed within 0.6 cm. Thermal imaging of increment cores provides a straightforward, low-cost, easy-to-use, and species-independent tool to identify sapwood depth. It has further potential to reveal radial differences in sapwood conductivity, to improve water balance estimations on larger scales and to quickly develop allometric relationships.

The Effect of Controlled Tile Drainage on Growth and Grain Yield of Spring Barley as Detected by UAV Images, Yield Map and Soil Moisture Content

Controlled tile drainage (CTD) practices are a promising tool for improving water balance, water quality and increasing crop yield by raising shallow groundwater level and capillary rise due to drainage flow retardation. We tested the effect of CTD on growth and grain yield of spring barley, at a study site in central Bohemia using vegetation indices from unmanned aerial vehicle (UAV) imagery and Sentinel-2 satellite imagery. Tile drainage flow was slowed by fixed water level control structures that increased soil moisture in the surrounding area according to the terrain slope. Vegetation indices based on red-edge spectral bands in combination with near-infrared and red bands were selected, of which the Normalized Red Edge-Red Index (NRERI) showed the closest relationships with shoot biomass parameters (dry biomass, nitrogen concentration and uptake, nitrogen nutrition index) from point sampling at the tillering stage. The CTD sites showed significantly more biomass using NRERI compared to free tile drainage (FTD) sites. In contrast, in the period prior to the implementation of CTD practices, Sentinel-2 satellite imagery did not demonstrate higher biomass based on NRERI at CTD sites compared to FTD sites. The grain yields of spring barley as determined from the yield map also increased due to CTD (by 0.3 t/ha, i.e., by 4%). The positive impact of CTD on biomass development and grain yield of spring barley was confirmed by the increase in soil moisture at depths of 20, 40 and 60 cm compared to FTD. The largest increase in soil water content of 3.5 vol% due to CTD occurred at the depth of 40 cm, which also had a higher degree of saturation of available water capacity and the occurrence of crop water stress was delayed by 14 days compared to FTD.

Developing a parsimonious canopy model (PCM v1.0) to predict forest gross primary productivity and leaf area index of deciduous broad-leaved forest

Abstract. Temperate forest ecosystems play a crucial role in governing global carbon and water cycles. However, unprecedented global warming presents fundamental alterations to the ecological functions (e.g., carbon uptake) and biophysical variables (e.g., leaf area index) of forests. The quantification of forest carbon uptake, gross primary productivity (GPP), as the largest carbon flux has a direct consequence on carbon budget estimations. Part of this assimilated carbon stored in leaf biomass is related to the leaf area index (LAI), which is closely linked to and is of critical significance in the water cycle. There already exist a number of models to simulate dynamics of LAI and GPP; however, the level of complexity, demanding data, and poorly known parameters often prohibit the model applicability over data-sparse and large domains. In addition, the complex mechanisms associated with coupling the terrestrial carbon and water cycles poses a major challenge for integrated assessments of interlinked processes (e.g., accounting for the temporal dynamics of LAI for improving water balance estimations and soil moisture availability for enhancing carbon balance estimations). In this study, we propose a parsimonious forest canopy model (PCM) to predict the daily dynamics of LAI and GPP with few required inputs, which would also be suitable for integration into state-of-the-art hydrologic models. The light use efficiency (LUE) concept, coupled with a phenology submodel, is central to PCM (v1.0). PCM estimates total assimilated carbon based on the efficiency of the conversion of absorbed photosynthetically active radiation into biomass. Equipped with the coupled phenology submodel, the total assimilated carbon partly converts to leaf biomass, from which prognostic and temperature-driven LAI is simulated. The model combines modules for the estimation of soil hydraulic parameters based on pedotransfer functions and vertically weighted soil moisture, considering the underground root distribution, when soil moisture data are available. We test the model on deciduous broad-leaved forest sites in Europe and North America, as selected from the FLUXNET network. We analyze the model's parameter sensitivity on the resulting GPP and LAI and identified, on average, 10 common sensitive parameters at each study site (e.g., LUE and SLA). The model's performance is evaluated in a validation period, using in situ measurements of GPP and LAI (when available) at eddy covariance flux towers. The model adequately captures the daily dynamics of observed GPP and LAI at each study site (Kling–Gupta efficiency, KGE, varies between 0.79 and 0.92). Finally, we investigate the cross-location transferability of model parameters and derive a compromise parameter set to be used across different sites. The model also showed robustness with the compromise single set of parameters, applicable to different sites, with an acceptable loss in model skill (on average ±8 %). Overall, in addition to the satisfactory performance of the PCM as a stand-alone canopy model, the parsimonious and modular structure of the developed PCM allows for a smooth incorporation of carbon modules to existing hydrologic models, thereby facilitating the seamless representation of coupled water and carbon cycle components, i.e., prognostic simulated vegetation leaf area index (LAI) would improve the representation of the water cycle components (i.e., evapotranspiration), while GPP predictions would benefit from the simulated soil water storage from a hydrologic model.