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Impacts of hydropower-induced flow alterations on composition and diversity of riparian vegetation in the Western Himalayas: A case study in Uttarakhand, India

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Journal of Mountain Science 2024年第4期21卷 1272-1286页

作者： Dharmveer KAINTURA Sabyasachi DASGUPTA Dhanpal Singh CHAUHAN Hemvati Nandan Bahuguna Garhwal University Srinagar Garhwal 246174India Tripura University SuryamaninagarAgartala 799022India

The increasing demand for water and energy resources has led to widespread dam construction,particularly in ecologically sensitive regions like the Himalayan Range.This study focuses on the Uttarakhand state in the Western Himalayas,where hydroelectric projects(HEPs)have significantly altered river flow regimes.The research investigates the impact of flow alterations on the composition and structure of riparian vegetation in the Garhwal Himalayas,specifically analysing four rivers regulated by hydroelectric projects.Utilizing the paired-reach comparison method,control(undisturbed),diverted(downstream of barrage/dam),and altered flow conditions(downstream of water outlet)were examined.The research reveals diverse and unique riparian ecosystems,with 89 genera and 113 taxa identified,showcasing the dominance of families like Asteraceae and Lamiaceae.The study unveils the structural importance of key species such as Berberis asiatica and Artemisia nilagirica.The density,diversity,and richness of shrub and herb species vary significantly across flow conditions.Notably,altered flow conditions demonstrate resilience in vegetation structure,while diverted conditions exhibit decreased species richness and density.The study emphasizes the importance of nuanced environmental flow management for mitigating adverse effects on riparian biodiversity in the fragile Himalayan region.These findings contribute to the global discourse on dam impacts and riparian ecology,shedding light on the complexities of this dynamic relationship in a vulnerable ecosystem.

关键词： Dam construction water stress Western Himalayas Disturbed flow regimes Riparian ecosystem

The unimodal latitudinal pattern of K,Ca and Mg concentration and its potential drivers in forest foliage in eastern China

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Forest Ecosystems 2024年第3期11卷 318-328页

作者： Zhijuan Shi Sining Liu Yahan Chen Dongdong Ding Wenxuan Han Key Laboratory of Plant-Soil Interactions Ministry of EducationCollege of Resources and Environmental SciencesChina Agricultural UniversityBeijing100193China Forestry Ecological Engineering in the Upper Reaches of the Yangtze River Key Laboratory of Sichuan Province&National Forestry and Grassland Administration Key Laboratory of Forest Resources Conservation and Ecological Safety on the Upper Reaches of the Yangtze River College of ForestrySichuan Agricultural UniversityChengdu611130China Institute of Botany Chinese Academy of SciencesBeijing100093China

Potassium(K),calcium(Ca),and magnesium(Mg)are essential elements with important physiological functions in plants.Previous studies showed that leaf K,Ca,and Mg concentrations generally increase with increasing latitudes.However,recent meta-analyses suggested the possibility of a unimodal pattern in the concentrations of these elements along latitudinal gradients.The authenticity of this unimodal latitudinal pattern,however,requires validation through large-scale field experimental data,and exploration of the underlying mechanisms if the pattern is confirmed.Here,we collected leaves of common species of woody plants from 19 montane forests in the north-south transect of eastern China,including 322 species from 160 genera,67 families;and then determined leaf K,Ca,and Mg concentrations to explore their latitudinal patterns and driving mechanisms.Our results support unimodal latitudinal patterns for all three elements in woody plants across eastern China,with peak values at latitude 36.5±1.0°N.The shift of plant-functional-type compositions from evergreen broadleaves to deciduous broadleaves and to conifers along this latitudinal span was the key factor contributing to these patterns.Climatic factors,mainly temperature,and to a lesser extent solar radiation and precipitation,were the main environmental drivers.These factors,by altering the composition of plant communities and regulating plant physiological activities,influence the latitudinal patterns of plant nutrient concentrations.Our findings also suggest that high leaf K,Ca,and Mg concentrations may represent an adaptive strategy for plants to withstand water stress,which might be used to predict plant nutrient responses to climate changes at large scales,and broaden the understanding of biogeochemical cycling of K,Ca,and Mg.

关键词： Potassium Calcium Magnesium Mid-latitudes Latitudinal pattern Plant functional type water stress Woody plant

water stress resilient cereal crops:Lessons from wild relatives

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Journal of Integrative Plant Biology 2022年第2期64卷 412-430页

作者： Justine M.Toulotte Chrysoula K.Pantazopoulou Maria Angelica Sanclemente Laurentius A.C.JVoesenek Rashmi Sasidharan Department of Biology Plant EcophysiologyInstitute of Environmental BiologyUtrecht UniversityUtrecht3584 CH The Netherlands

Cereal crops are significant contributors to global diets.As climate change disrupts weather patterns and wreaks havoc on crops,the need for generating stress-resilient,high-yielding varieties is more urgent than ever.One extremely promising avenue in this regard is to exploit the tremendous genetic diversity expressed by the wild ancestors of current day crop species.These crop wild relatives thrive in a range of environments and accordingly often harbor an array of traits that allow them to do so.The identification and introgression of these traits into our staple cereal crops can lessen yield losses in stressful environments.In the last decades,a surge in extreme drought and flooding events have severely impacted cereal crop production.Climate models predict a persistence of this trend,thus reinforcing the need for research on water stress resilience.Here we review:(i)how water stress(drought and flooding)impacts crop performance;and(ii)how identification of tolerance traits and mechanisms from wild relatives of the main cereal crops,that is,rice,maize,wheat,and barley,can lead to improved survival and sustained yields in these crops under water stress conditions.

关键词： abiotic stress cereal crops climate change crop wild relatives drought flooding grass water stress

Effects of water stress on quality and sugar metabolism in'Gala'apple fruit

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Horticultural Plant Journal 2023年第1期9卷 60-72页

作者： Hongxia Tao Hanqing Sun Yufei Wang Xin Wang Yanping Guo College of Horticulture Northwest A&F UniversityYanglingShaanxi 712100China

Sugar plays an important role in apple fruit development,appearance and quality as well as contributing to a plant’s water stress response.Trehalose and the trehalose biosynthetic metabolic pathways are part of the sugar signaling system in plants,which are important regulator of water stress response in apple.The effect of water stress treatments applied to apple trees and the corresponding effects of ABA on developmental fruit quality were examined for indicators of fruit quality during fruit development.The results indicated that the severe water stress treatment(W2)occurring after the last stage of fruit cell division caused a decrease in the color and size of fruit.The moderate water stress(W1)occurring after the last stage of fruit cell enlargement(S2)caused an increase in the content of fructose and sorbitol while the apple fruit shape was not affected.These changes in sugar are related to the activity of sugar metabolic enzymes.While the enzymatic activity of vacuolar acid invertase(vAINV)was higher,that of sucrose-phosphate synthase(SPS)was lower in water stress treated fruit throughout the developmental period.This indicates that enhanced sucrose degradation and reduced sucrose synthesis leads to an overall reduced sucrose content during times of drought.Thus,water stress reduced sucrose content.Whereas the content of endogenous trehalose and ABA were the highest in water stress treated fruit.A moderate water stress(W1)imposed on apple trees via water restriction(60%–65%of field capacity)after the fruit cell enlargement phase of fruit development yielded sweeter fruit of higher economic value.

关键词： Apple water stress Quality Sugar metabolism Trehalose ABA

Physiological Response Mechanism and Drought Resistance Evaluation of Passiflora edulis Sims under Drought stress

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Phyton-International Journal of Experimental Botany 2024年第6期93卷 1345-1363页

作者： Binyang Zhao Fengchan Wu Guojun Cai Peiyu Xi Yulin Guo Anding Li College of Forestry Guizhou UniversityGuiyang550025China Guizhou Institute of Biology Guizhou Academy of SciencesGuiyang550009China College of Resources and Environment Hunan Agricultural UniversityChangsha410128China

In order to explore the response mechanism of Passiﬂora edulis Sims to drought stress,the changes in morpho-logical and physiological traits of Passiﬂora edulis Sims under different drought conditions were studied.A total of 7 germplasm resources of Passiﬂora edulis Sims were selected and tested under drought stress by the pot culture method under 4 treatment levels:75%–80%(Control,CK)of maximumﬁeld water capacity,55%–60%(Light Drought,LD)of maximumﬁeld water capacity,i.e.,mild drought,40%–45%(Moderate Drought,MD)of max-imumﬁeld water capacity,i.e.,moderate drought and 30%–35%(Severe Drought,SD)of maximumﬁeld water capacity,i.e.,severe drought.On the 40th day of drought treatment,13 indices,including seedling growth mor-phology,physiology,and biochemistry,were measured.The results showed that under drought stress,the height and ground diameter of P.edulis Sims gradually decreased with increasing drought stress,and there were signiﬁ-cant differences in seedling height and ground diameter among the treatments.Drought stress signiﬁcantly inhib-ited the growth of seven P.edulis Sims varieties.The contents of soluble sugar(SS),soluble protein(SP),proline(Pro),and other substances in P.edulis Sims basically increased with increasing drought stress.With the aggrava-tion of drought stress,the malondialdehyde(MDA)content of P.edulis Sims tended to increase to different degrees,the superoxide dismutase(SOD)activity and peroxidase(POD)activity both tended to increase atﬁrst and then decrease,and the change in catalase(CAT)activity mostly showed a gradual increasing trend.The con-tents of endogenous hormones in P.edulis Sims signiﬁcantly differed under different degrees of drought stress.With the aggravation of drought stress,the abscisic acid(ABA)content of P.edulis Sims tended to increase,whereas the contents of gibberellin(GA),indoleacetic acid(IAA),and zeatin nucleoside(ZR)exhibited a down-ward trend.A comprehensive evaluation of the drought resistance of seven P.edulis Sims varieties was conducted based on the principal

关键词： Drought resistance water stress phytohormone morphological trait physiological traits

An Automatic Classification Grading of Spinach Seedlings water stress Based on N-MobileNetXt

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Intelligent Automation & Soft Computing 2023年第9期37卷 3019-3037页

作者： Yanlei Xu Xue Cong Yuting Zhai Zhiyuan Gao Helong Yu School of Information Technology Jilin Agricultural UniversityChangchun130118China

To solve inefficient water stress classification of spinach seedlings under complex background,this study proposed an automatic classification method for the water stress level of spinach seedlings based on the N-MobileNetXt(NCAM+MobileNetXt)network.Firstly,this study recon-structed the Sandglass Block to effectively increase the model accuracy;secondly,this study introduced the group convolution module and a two-dimensional adaptive average pool,which can significantly compress the model parameters and enhance the model robustness separately;finally,this study innovatively proposed the Normalization-based Channel Attention Module(NCAM)to enhance the image features obviously.The experimental results showed that the classification accuracy of N-MobileNetXt model for spinach seedlings under the natural environment reached 90.35%,and the number of parameters was decreased by 66%compared with the original MobileNetXt model.The N-MobileNetXt model was superior to other net-work models such as ShuffleNet and GhostNet in terms of parameters and accuracy of identification.It can provide a theoretical basis and technical support for automatic irrigation.

关键词： Deep learning water stress grade classification image processing complex background

Expression of MaMAPK Gene in Seedlings of Malus L.under water stress

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Acta Biochimica et Biophysica Sinica 2006年第4期38卷 281-286页

作者： Li-Xin PENG~(1,2) Ling-Kun GU~2 Cheng-Chao ZHENG~2 De-Quan LI~2* Huai-Rui SHU~2 1 Department of Horticulture,Tianjin Agricuhural College,Tianjin 300384,China 2 College of Life Science,Shandong Agricultural University,Tai'an 271018,China Department of Horticulture Tianjin Agricultural CollegeTianjin 300384 China College of Life Science Shandong Agricultural UniversityTai'an 271018 China

Seedlings of three species of Malus were used to study the expression of mitogen-activatedprotein kinase (MAPK) in response to water stress:Malus hupehensis,a drought-sensitive species;Malussieversii,a drought-tolerant species;and Malus micromalus,a middle type.Results showed that MalusMAPK (MaMAPK,GenBank accession No.AF435805) was expressed in both roots and leaves of seedlingsof the three Malus species treated with 20% polyethylene glycol for different time periods.Expression levelspeaked at 1.5 h after treatment with polyethylene glycol,then decreased to their lowest levels.Liquid kinaseassays indicated that the dynamic changes of MAPK activity were very similar to those of the relativeexpression of MaMAPK mRNA.However,the peak of the former occurred slightly behind the latter.It wasnoticed that,although the kinase activity decreased after the peak,it was still higher than that of the controlduring the whole time period.These results suggested that MaMAPK was regulated not only by water stressat the transcription level,but also by phosphorylation and dephosphorylation at the protein level.In addition,of these three apple species,the highest MAPK activity and MaMAPK expression level was found in M.sieversii,followed by M.micromalus and M.hupehensis,suggesting that MAPK might be correlated withdrought tolerance in these three species.The different expression levels might be one of the molecularmechanisms of the different drought tolerances in Malus.

关键词： expression characteristics Malus L. MaMAPK gene water stress

water stress Effect on Biochemical Processes of Aus Rice Genotypes

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American Journal of Plant Sciences 2022年第6期13卷 912-927页

作者： Halima Sayeed Jasmine Kamal Uddin Ahamed Jiban Krishna Biswas Sher-e-Bangla Agricultural Research System (SAURES) Sher-e-Bangla Agricultural University (SAU) Dhaka Bangladesh Department of Agricultural Botany Sher-e-Bangla Agricultural University (SAU) Dhaka Bangladesh Bangladesh Rice Research Institute (BRRI) Gazipur Bangladesh

An experiment was carried out at Sher-e-Bangla Agricultural University, Dhaka, Bangladesh during the period from March to July 2014. Plants were grown in the rain-protected polyethylene shelter or shed to avoid rain under natural conditions. The experiment was conducted on biochemical characters of aus rice varieties in various soil moisture levels in three rice genotypes as BRRI dhan55 (V1), BR6976-2B-15 (V2), and tolerant check Hashikalmi (V3), and seven water stress were imposed as treatments. Treatments were 0 days of water stress (control) irrigated continuously throughout the experimental period (T0). From twenty days onwards water stress was imposed for seven days when the age of the seedling was 20 days (T1), 35 days (T2), 55 days (T3), 75 days (T4), 95 days (T5), and 115 days (T6). Our findings suggest that the proline, starch, and sugar content were also found comparatively higher in BRRI dhan55 and Hashikalmi among the genotypes under water stress conditions. Under water stress conditions, proline was accumulated, sugar, and starch were decreased. The soluble sugar content was much lower under water stress conditions due to lower RWC, chlorophyll content, stomatal conductance, and higher leaf rolling. Leaf accumulates anthocyanins under drought conditions and the red color increased as the intensity of water stress increased.

关键词： water stress Genotypes Proline Starch and Sugar

water stress Early Detection of Eggplant Plants by Hyperspectral Fluorescence Spectroscopy

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Open Journal of Applied Sciences 2023年第3期13卷 343-354页

作者： Amara Kamate Penetjiligué Adama Soro Emma Georgina Zoro-Diama Kedro Sidiki Diomande Adjo Viviane Adohi-Krou Laboratoire des Sciences de la Matière de l’Environnement et de l’Energie Solaire (LASMES) Université Félix Houphouët-Boigny Abidjan Côte d’Ivoire Centre National de Recherche Agronomique (CNRA) Adiopodoumé Côte d’Ivoire

water stress early detection is essential for precision farming to improve crop productivity and product quality. The methods usually used are destructive, long and expensive. In this work, we used hyperspectral chlorophyll fluorescence technology as a rapid, non-destructive approach to detect the water deficiency of eggplant plants using their spectral footprint. So, an experiment was made on 54 eggplant plants subjected to three water treatments: normal irrigation (T100), intermediate irrigation (T50) and no irrigation (T0). The fluorescence spectra were acquired in vivo and in situ using a USB4000 spectrometer from Ocean optics. For the classification of the plants subjected to three water treatments, we used three pretreatments of the raw hyperspectral data in order to suppress the non-informative variability present in these spectra and to obtain robust models. These are the Savitzky-Golay smoothing (SG), the standard normal variable (SNV) and the first derivative of Savitzky-Golay (SG-D1). The preprocessed data were then subjected to two partial least squares discriminant analyses (PLS-DA): Hard PLS-DA and Soft PLS-DA. These statistical approaches are suitable for large samples as it reduces the dimensionality of the data but improves the accuracy of the prediction. The SG-D1 combined with the Soft PLS-DA gave the best discrimination of plants with scores of sensitivity, specificity and total efficiency respectively of 97.33%, 94% and 95% for calibration, 6 days after hydric stress induction. For the plants used for the prediction, the scores are 86%, 91% and 90% respectively. This study shows that hyperspectral chlorophyll fluorescence spectroscopy is a fast and non-destructive technology allowing early detection of water stress in eggplant plants.

关键词： Chlorophyll Fluorescence Eggplant water stress water Deficiency PLS-DA