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Shenzhen Yinle Aerated Water Plant
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作者 Li Hang 《China's Foreign Trade》 1996年第2期45-45,共1页
The Shenzhen Yinle AeratedWater Plant,set up in 1981 jointly byPepsi Cola Inc.of the US and theShenbao Company of Shenzhen,wasPepsi Cola’s first bottling plant inChina's Mainland.Through the jointefforts of the t... The Shenzhen Yinle AeratedWater Plant,set up in 1981 jointly byPepsi Cola Inc.of the US and theShenbao Company of Shenzhen,wasPepsi Cola’s first bottling plant inChina's Mainland.Through the jointefforts of the two sides over a dozenyears,the plant’s production has beenconstantly expanded,with growingoutput and improved quality andefficiency.By the end of June,it hadretained an accumulative total of pre-tax profits of RMB233 million.Takinginto account the profits earned by theAmerican side from the sale of cola,the total profits earned by both sideshave exceeded the initial investmentover 20 times. 展开更多
关键词 OVER Shenzhen Yinle Aerated water plant US
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Distribution of High Water Plants of Lake Karakir in Bukhara Region in Ecological Groups 被引量:1
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作者 Kobilov Aziz Mukhtorovich Buriev Sulaymon Burievich 《American Journal of Plant Sciences》 2019年第12期2203-2207,共5页
In this article, information about the geographical location of the Karakir Lake in Bukhara region, high water plants, systematics and their distribution is presented. As a result of the research, Lake Karakir has 34 ... In this article, information about the geographical location of the Karakir Lake in Bukhara region, high water plants, systematics and their distribution is presented. As a result of the research, Lake Karakir has 34 species of high water plants belonging to 16 families. These plants were divided into ecological groups and analyzed. 展开更多
关键词 DITCH Gidrobiont HIGH water plants Eftrophication AQUARIUM Karakir Filtration REED CATTAIL Pondweed
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A Case Study on the Utilization of Wind Energy Potential on Remote and Isolated Small Wastewater Plants 被引量:1
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作者 Joao Femando Pereira Gomes Pedro Manuel Saraiva Cardoso 《Journal of Energy and Power Engineering》 2012年第4期554-560,共7页
关键词 小型污水处理厂 风能 案例 风力涡轮机 网站定位 能源供应 潜力评价 历史数据
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Grain yield and N uptake of maize in response to increased plant density under reduced water and nitrogen supply conditions
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作者 Jingui Wei Qiang Chai +5 位作者 Wen Yin Hong Fan Yao Guo Falong Hu Zhilong Fan QimingWang 《Journal of Integrative Agriculture》 SCIE CSCD 2024年第1期122-140,共19页
The development of modern agriculture requires the reduction of water and chemical N fertilizer inputs.Increasing the planting density can maintain higher yields,but also consumes more of these restrictive resources.H... The development of modern agriculture requires the reduction of water and chemical N fertilizer inputs.Increasing the planting density can maintain higher yields,but also consumes more of these restrictive resources.However,whether an increased maize density can compensate for the negative effects of reduced water and N supply on grain yield and N uptake in the arid irrigated areas remains unknown.This study is part of a long-term positioning trial that started in 2016.A split-split plot field experiment of maize was implemented in the arid irrigated area of northwestern China in 2020 to 2021.The treatments included two irrigation levels:local conventional irrigation reduced by 20%(W1,3,240 m^(3)ha^(-1))and local conventional irrigation(W2,4,050 m^(3)ha^(-1));two N application rates:local conventional N reduced by 25%(N1,270 kg ha^(-1))and local conventional N(360 kg ha^(-1));and three planting densities:local conventional density(D1,75,000 plants ha^(-1)),density increased by 30%(D2,97,500 plants ha-1),and density increased by 60%(D3,120,000 plants ha^(-1)).Our results showed that the grain yield and aboveground N accumulation of maize were lower under the reduced water and N inputs,but increasing the maize density by 30% can compensate for the reductions of grain yield and aboveground N accumulation caused by the reduced water and N supply.When water was reduced while the N application rate remained unchanged,increasing the planting density by 30% enhanced grain yield by 13.9% and aboveground N accumulation by 15.3%.Under reduced water and N inputs,increasing the maize density by 30% enhanced N uptake efficiency and N partial factor productivity,and it also compensated for the N harvest index and N metabolic related enzyme activities.Compared with W2N2D1,the N uptake efficiency and N partial factor productivity increased by 28.6 and 17.6%under W1N1D2.W1N2D2 had 8.4% higher N uptake efficiency and 13.9% higher N partial factor productivity than W2N2D1.W1N2D2 improved urease activity and nitrate reductase activity by 5.4% at the R2(blister)stage and 19.6% at the V6(6th leaf)stage,and increased net income and the benefit:cost ratio by 22.1 and 16.7%,respectively.W1N1D2 and W1N2D2 reduced the nitrate nitrogen and ammoniacal nitrogen contents at the R6 stage in the 40-100 cm soil layer,compared with W2N2D1.In summary,increasing the planting density by 30% can compensate for the loss of grain yield and aboveground N accumulation under reduced water and N inputs.Meanwhile,increasing the maize density by 30% improved grain yield and aboveground N accumulation when water was reduced by 20% while the N application rate remained constant in arid irrigation areas. 展开更多
关键词 water and N reduction plant density MAIZE grain yield N uptake compensation effect
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Variation of soil-plant-atmosphere continuum stable isotope and water source in Qinghai spruce forest of the eastern Qilian Mountains 被引量:1
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作者 ZHOU Jun-ju WANG Xue +9 位作者 MA Luo LUO Chu-yu TANG Hai-tao GUO Zhao-nan CHEN Jia-wei SHI Su-han SHI Wei WEI Wei ZHANG Dong-xia LIU Chun-fang 《Journal of Mountain Science》 SCIE CSCD 2023年第2期355-366,共12页
Understanding the hydrogen and oxygen stable isotope composition and characteristics of different water bodies in soil-plant-atmosphere continuum is of significance for revealing regional hydrological processes and wa... Understanding the hydrogen and oxygen stable isotope composition and characteristics of different water bodies in soil-plant-atmosphere continuum is of significance for revealing regional hydrological processes and water cycle mechanisms.In this study,we analyzed the stable isotopic composition,relationship and indicative significance of precipitation,soil water(0~100 cm depth)and xylem water of Qinghai spruce(Picea crassifolia)forest in the eastern Qilian Mountains,and explored the circulation process among different water bodies.The results show that the stable isotopes of precipitation vary greatly during the entire observation period.The values ofδ2H andδ^(18)O in the precipitation in the warm season are richer than those in the cold season,and the slope and intercept of local meteoric water line(LMWL,δ2H=6.79δ18O+7.13)are both smaller than global meteoric water line(GMWL,δ2H=8.17δ18O+10.56).The stable isotopes of soil water at different depths underwent different degrees of evaporative fractionation,and theδ18O andδ2H of shallow soil water varied greatly,while the deep soil water tended to be similar.The topsoil(0~10 cm)can respond quickly to precipitation,and the response of the deep soil has a time lag.In the whole growing season,0~30 cm and 60~100 cm soil water are the main water sources of Qinghai spruce.The water source of Qinghai spruce was from all soil layers in May and September,mainly from the shallow soil layer(0~30 cm)in August and October,and mainly from the deep soil layer(60~100 cm)in June and July. 展开更多
关键词 Stable hydrogen isotope Stable oxygen isotope Soil-plant-atmosphere continuum SPAC plant water use IsoSource model
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Biological Waste Water Hyacinth (Eichhornia crassipes) Plant Powder Particle with Eggshell Filler-reinforced Epoxy Polymer Composite Material Property Analysis
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作者 Ajithram Arivendan Winowlin Jappes Jebas Thangiah +1 位作者 Sumesh Ramakrishnan Dawood Ahmed Desai 《Journal of Bionic Engineering》 SCIE EI CSCD 2023年第3期1386-1399,共14页
In this study, water hyacinth powder-reinforced polymer composites with eggshell filler material are investigated for their mechanical, absorption, morphological, thermal, and characterization properties. Hyacinth pow... In this study, water hyacinth powder-reinforced polymer composites with eggshell filler material are investigated for their mechanical, absorption, morphological, thermal, and characterization properties. Hyacinth powder particles have not been extensively studied in polymer composites. This study investigates the use of eggshell powder for composites made from hyacinth powder. The use of hyacinth powder improves the mechanical properties of composites. With the help of the powder particles, composite samples are produced by compression moulding using an epoxy polymer matrix. 5% eggshell filler varied from 18.25 to 33.64 MPa for tensile strength, 40.28–49.66 MPa for flexural strength, and 2.45–4.75 J for impact strength. X-ray diffraction and Fourier transforms can be used to determine chemical groups, function groups, and crystallinity indexes. Powder particles can be observed by scanning electron microscopes in terms of their bonding behavior, eggshell powder combinations, and primary- and secondary-phase material absorption. According to the research presented in this paper, commercial particleboard applications can benefit substantially from hyacinth powder particles reinforced with eggshell fillers. 展开更多
关键词 water hyacinth plant powder Bioinspired composites Mechanical properties Hardness Absorption studies XRD FTIR SEM
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基于Plant Simulation的压气机叶片型线加工产线分析与优化
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作者 李春兴 徐健 +3 位作者 易泰勋 王琨 吴海峰 胡诚诚 《机械制造与自动化》 2024年第1期40-44,共5页
运用专业仿真软件Plant Simulation,根据压气机叶片型线机械加工工艺特点和物料运行流程建立生产线仿真模型,从产能、设备利用率及产线瓶颈等多方面进行仿真分析与优化。结果表明:Plant Simulation仿真平台的仿真可以找出规划设计方案... 运用专业仿真软件Plant Simulation,根据压气机叶片型线机械加工工艺特点和物料运行流程建立生产线仿真模型,从产能、设备利用率及产线瓶颈等多方面进行仿真分析与优化。结果表明:Plant Simulation仿真平台的仿真可以找出规划设计方案中存在的问题并验证方案的合理性。该仿真结果为型线机械加工产线的优化设计提供了可靠依据,达到了节约投资成本和缩短设计周期的目的。 展开更多
关键词 plant Simulation 规划 叶片 生产线
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Assessment of Super Absorbent Polymer (SAP) on Plant Available Water (PAW) in Dry Lands
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作者 Vincent Ng’eno Christian Omuto +1 位作者 Duncan Mbuge Vitalis Too 《Engineering(科研)》 CAS 2023年第2期90-105,共16页
One of the ways of overcoming the cost of irrigation is through in-situ water harvesting at the plant roots. Super absorbent polymer (SAP) can facilitate water harvesting at the plant roots. This study attempted to as... One of the ways of overcoming the cost of irrigation is through in-situ water harvesting at the plant roots. Super absorbent polymer (SAP) can facilitate water harvesting at the plant roots. This study attempted to assess the effect of SAP on plant available water (PAW) of different soils. In this study, SAP was sequentially added at the rate of 0.2%, 0.3% and 0.5% of the soil weight and its impact assessed in clay, sandy clay and sandy loam soils. The moisture retention characteristics of the original and SAP treated soils were studied using soil water retention curves (SWRC) and results modelled using Gardner model. PAW was estimated from SWRC as the difference between moisture content at 1.5 and 3 bar in all soils. The difference in PAW between original and treated soils was assessed at 5% level of significance. The WRC of all the samples was adequately found to be described by the Gardner model (Coefficient of determination R<sup>2</sup> ≥ 98% and residual standard error (RSE) ≤ 0.04). SWRC changed with increase in SAP percentage in clay, sandy clay and sandy loam soils. Clay had a higher change in water retention then sandy clay and lastly sandy loam. Plant available water content (PAW) in all soils increased. In clay soil it increased with increase in SAP from 0.3291 at zero SAP to 0.6223 at 0.5% SAP. Sandy clay soil increased in PAW from 0.2721 at zero SAP to 0.5335 at 0.5% SAP and Sandy loam soils from 0.1691 at zero SAP to 0.3461 at 0.5% SAP. Hence, from the study SAP can be used to conserve irrigation water in the plant roots and therefore reducing the cost since PAW has been increased. 展开更多
关键词 plant Available water (PAW) Soil water Retention Curve (SWRC) SOIL Super Absorbent Polymer (SAP)
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Contribution of Herbaceous Plants and Their Status and Role in Soil and Water Ecosystem
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作者 Fazheng SUN Chengyan HUANG Rong HU 《Meteorological and Environmental Research》 CAS 2023年第5期7-10,13,共5页
In this paper,the contemporary understanding process of herbaceous plants and their contributions are elaborated.The systematic idea of"mountain,river,forest,field,lake,and grass are a community of life"has ... In this paper,the contemporary understanding process of herbaceous plants and their contributions are elaborated.The systematic idea of"mountain,river,forest,field,lake,and grass are a community of life"has led the grass to enter a new era of development.Broadly speaking,vegetation includes grassland,forest,crop,garden,etc.,while herbaceous vegetation is the most widely distributed on earth.From the macro and micro perspectives of soil and water ecology,this paper discusses the position and role of herbaceous vegetation in the earth's soil and water ecosystem,especially the fundamental position in mountain,river,forest,field,lake,grass and sand.Starting from the concept of soil and water ecology,the integrated protection and systematic management of mountain,river,forest,field,lake,grassland,and sand is proposed.Essentially,it is the protection and management of soil and water ecology,which summarizes various ecological systems on earth.The successful application of herbaceous plants in ecological restoration projects of mine has further enriched and developed the theory of soil and water ecology. 展开更多
关键词 Herbaceous plant Soil and water ecosystem Theory of soil and water ecology Application
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The Ability of Some Aquatic and Terrestrial Plants to Purify Domestic Wastewater
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作者 Abida Kausar Noreen Zahra +3 位作者 Humaira Kiran Sadia Asim Abid Raza Ali Raza 《Phyton-International Journal of Experimental Botany》 SCIE 2023年第8期2245-2260,共16页
The study aimed to evaluate the ability of some terrestrial and aquatic plants for wastewater purification.Aquatic plants can remove pollutants from wastewater by consuming and accumulating various contaminants in diff... The study aimed to evaluate the ability of some terrestrial and aquatic plants for wastewater purification.Aquatic plants can remove pollutants from wastewater by consuming and accumulating various contaminants in different parts of plants.Different aquatic and terrestrial plants(Rosa sinensis,Typha latifolia,Ocimm bacilicum,Azolla pinnata,and Salvinia molesta)which have the ability to decrease water pollution were utilized in this study.The capability offive different species of plants was investigated by measuring chemical oxygen demand(COD),biological oxygen demand(BOD),electrical conductivity(EC),total dissolved solids(TDS),and pH of the medium.In this research,some aquatic and terrestrial plants were transplanted in wastewater plastic pots containing domestic wastewater with different ratios of 50%and 100%.Then,after 30 days,the physiological and biochemical parameters of plants were calculated to observe the effect of wastewater on plants.Results revealed higher chlorophyll and carotenoids in typha plants treated with 100%wastewater.The highest percentage of elimination in BOD(65%),COD(27%),TDS(72%),EC(83%),and pH(6.8%)was noted with the use of typha and azolla.Intriguingly,total soluble sugars,total free amino acids,and total proteins were found maximum in the hibiscus plant as compared to the other plants under 100%and 50%domestic wastewater treatment,while typha and ocimum showed lower values of these parameters irrespective of wastewater treatments.Moreover,the COD,BOD,TDS,EC,and pH trend was higher in 100%wastewater as compared to 50%wastewater.Taking into account the accumulation capacity of the tested plants especially typha can be efficiently used for the treatment of domestic wastewater. 展开更多
关键词 Biological oxygen demand chemical oxygen demand domestic wastewater aquatic plants terrestrial plants
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Water Stress Early Detection of Eggplant Plants by Hyperspectral Fluorescence Spectroscopy
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作者 Amara Kamate Penetjiligué Adama Soro +2 位作者 Emma Georgina Zoro-Diama Kedro Sidiki Diomande Adjo Viviane Adohi-Krou 《Open Journal of Applied Sciences》 CAS 2023年第3期343-354,共12页
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 chlor... 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 (T<sub>100</sub>), intermediate irrigation (T<sub>50</sub>) and no irrigation (T<sub>0</sub>). 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. 展开更多
关键词 Chlorophyll Fluorescence EGGplant water Stress water Deficiency PLS-DA
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Response of dryland crops to climate change and drought-resistant and water-suitable planting technology:A case of spring maize
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作者 FAN Ting-lu LI Shang-zhong +5 位作者 ZHAO Gang WANG Shu-ying ZHANG Jian-jun WANG Lei DANG Yi CHENG Wan-li 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第7期2067-2079,共13页
Climate change has a significant impact on agriculture.However,the impact investigation is currently limited to the analysis of meteorological data,and there is a dearth of long-term monitoring of crop phenology and s... Climate change has a significant impact on agriculture.However,the impact investigation is currently limited to the analysis of meteorological data,and there is a dearth of long-term monitoring of crop phenology and soil moisture associated with climate change.In this study,temperature and precipitation(1957-2020)were recorded,crop growth(1981-2019)data were collected,and field experiments were conducted at central and eastern Gansu and southern Ningxia,China.The mean temperature increased by 0.36°C,and precipitation decreased by 11.17 mm per decade.The average evapotranspiration(ET)of winter wheat in 39 years from 1981 to 2019 was 362.1 mm,demonstrating a 22.1-mm decrease every 10 years.However,the ET of spring maize was 405.5 mm over 35 years(1985-2019),which did not show a downward trend.Every 10 years,growth periods were shortened by 5.19 and 6.47 d,sowing dates were delayed by 3.56 and 1.68 d,and maturity dates advanced by 1.76 and 5.51 d,respectively,for wheat and maize.A film fully-mulched ridge-furrow(FMRF)system with a rain-harvesting efficiency of 65.7‒92.7%promotes deep rainwater infiltration into the soil.This leads to double the soil moisture in-furrow,increasing the water satisfaction rate by 110‒160%.A 15-year grain yield of maize increased by 19.87%with the FMRF compared with that of half-mulched flat planting.Grain yield and water use efficiency of maize increased by 20.6 and 17.4%when the density grew from 4.5×10^(4)to 6.75×10^(4)plants ha-1 and improved by 12.0 and 12.7%when the density increased from 6.75×10^(4)to 9.0×10^(4)plants ha-1,respectively.Moreover,responses of maize yield to density and the corresponding density of the maximum yield varied highly in different rainfall areas.The density parameter suitable for water planting was 174 maize plants ha-1 with 10 mm rainfall.Therefore,management strategies should focus on adjusting crop planting structure,FMRF water harvesting system,and water-suitable planting to mitigate the adverse effects of climate change and enhance sustainable production of maize in the drylands. 展开更多
关键词 climate change dryland maize and wheat plastic mulch water-suitable planting
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SimET: An open-source tool for estimating crop evapotranspiration and soil water balance for plants with multiple growth cycles
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作者 Minguo Liu Mei Yang Huimin Yang 《The Crop Journal》 SCIE CSCD 2023年第5期1579-1585,共7页
Accurate estimation of crop evapotranspiration(ETc) and soil water balance, which is vital for optimizing water management strategy in crop production, can be performed by simulation. But existing software has many de... Accurate estimation of crop evapotranspiration(ETc) and soil water balance, which is vital for optimizing water management strategy in crop production, can be performed by simulation. But existing software has many deficiencies, including complex operation, limited scalability, lack of batch processing, and a single ETc model. Here we present simET, an open-source software package written in the R programming language. Many concepts involved in crop ETc simulation are condensed into functions in the package. It includes three widely used crop ETc models built on these functions: the single-crop coefficient,double-crop coefficient, and Shuttleworth–Wallace models, along with tools for preparing model data and comparing estimates. SimET supports ETc simulation in crops with repeated growth cycles such as alfalfa, a perennial forage crop that is cut multiple times annually. 展开更多
关键词 Crop evapotranspiration Soil water balance Evapotranspiration model R package
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Stable Isotopic Signatures of NO3 in Waste Water Effluent and Los Angeles River
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作者 Isaac Hall Mohammad Hassan Rezaie Boroon 《Journal of Water Resource and Protection》 CAS 2024年第1期102-122,共21页
A metropolitan city such as Los Angeles (LA) is an ideal study site with a very high population density, and it houses at least 3 treatment plants where sewage is treated preliminarily and then progressing to tertiary... A metropolitan city such as Los Angeles (LA) is an ideal study site with a very high population density, and it houses at least 3 treatment plants where sewage is treated preliminarily and then progressing to tertiary treatment before discharging into the LA River. We will gain a better understanding of the water quality in the LA River and the nitrate load in the watershed system by examining the influence of waste water treatment plants (WWTPs). The goal of this study is to pinpoint the exact source of nitrate in the LA River using the isotope signatures. We have selected sampling locations both upstream and downstream of the WWTP. This serves to monitor nitrate levels, aiding in the assessment of treatment plant effectiveness, pinpointing nitrate pollution sources, and ensuring compliance with environmental regulations. The research explores the isotopic composition of NO3 in relation to atmospheric nitrogen and Vienna Standard Mean Ocean Water, shedding light on the contributions from various sources such as manure, sewage, soil organic nitrogen, and nitrogen fertilizers. Specifically, there is a change in the δ15NAir value between the dry and wet seasons. The isotope values in the Tillman WWTP sample changed between dry and wet seasons. Notably, the presence of nitrate originating from manure and sewage is consistent across seasons, emphasizing the significant impact of anthropogenic and agricultural activities on water quality. This investigation contributes to the broader understanding of nitrogen cycling in urban water bodies, particularly in the context of wastewater effluent discharge. The findings hold implications for water quality management and highlight the need for targeted interventions to mitigate the impact of nitrogen-containing compounds on aquatic ecosystems. Overall, the study provides a valuable framework for future research and environmental stewardship efforts aimed at preserving the health and sustainability of urban water resources. This data informs decisions regarding additional treatment or mitigation actions to safeguard downstream water quality and ecosystem health. 展开更多
关键词 Metropolitan City Los Angeles Treatment plants Sewage Treatment Nitrate Source Isotope Signatures water Quality
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The Effects of Water and Fertilizer Coupling on Plant and Soil Nitrogen Characteristics and Fruit Growth of Rabbiteye Blueberry Plants in a Semi-Arid Region in China
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作者 Xiaolan Guo Di Zhao +3 位作者 Jinbin Hu Delu Wang Jianbin Wang Muhammad Shakeel 《Phyton-International Journal of Experimental Botany》 SCIE 2023年第1期209-223,共15页
To evaluate the effects of nitrogen(N)and irrigation coupling on the soil N distribution,plant N utilization,and fruit yield of rabbiteye blueberries(Vaccinium virgatum),a field experiment was designed using two facto... To evaluate the effects of nitrogen(N)and irrigation coupling on the soil N distribution,plant N utilization,and fruit yield of rabbiteye blueberries(Vaccinium virgatum),a field experiment was designed using two factors(water and fertilizer application)with four levels of irrigation and three levels of fertilization,and a control.Under the different water and fertilizer combinations,N primarily accumulated in the leaves.Irrigation and N application within appropriate ranges(pure N≤29 g/plant and irrigation volume≤2.5 L/plant)significantly improved the blueberry fruit yield.Increases in water and N within these ranges promoted the effective accumulation of N in various organs and the absorption and utilization of N in the plants,which ultimately promoted blueberry yield.With increased N application rate,the nitrate N content of the 0–20 cm and 20–50 cm soil layers increased.With increased irrigation volume,the nitrate N content of the 0–20 cm soil layer decreased,while the nitrate content in the 20–50 cm soil layer increased.Low N and moderate water treatments resulted in high fruit yields and reduced nitrate N retention in the soil.Under these conditions,the economic input-output ratio was high and the soil N accumulation was low,and thus the economic and ecological benefits were maximized. 展开更多
关键词 Vaccinium virgatum soil nitrogen distribution plant nitrogen utilization fruit yield
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Land Use and Environmental Gradients Influence on Riparian Woody Plant Diversity and Structure in Lake Manyara Watershed Ecosystem, Tanzania
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作者 Almas Kashindye Richard A. Giliba +2 位作者 Mathew M. Mpanda Mwemezi J. Rwiza Juma R. Selemani 《Open Journal of Ecology》 2023年第9期633-648,共16页
Riparian vegetations are important in supporting ecological connectivity between aquatic and terrestrial ecosystems. The structure and species composition of riparian woody plants have been subjected to multiple force... Riparian vegetations are important in supporting ecological connectivity between aquatic and terrestrial ecosystems. The structure and species composition of riparian woody plants have been subjected to multiple forces with varying degree of influences. This study examined the influence of land use and environmental gradient to the structure and composition of the riparian woody plants in northern Tanzania. A total of 270 plots were surveyed for woody plant species in the riparian ecosystems and later analysed to determine the influence of land use categories (homegarden, crop field, woodlot, open canopy forest, and closed canopy forest) and environmental variables (temperature, precipitation, elevation and slope) to the species richness, abundance, and stand parameters. Basal area was higher in woodlots, homegardens and crop fields than in the open and closed canopy forests;and as expected the reverse was true for the number of stocking density. Correlation among stand parameters with environmental variables varied significantly. Species richness and species abundance were negatively correlated to precipitation, temperature and elevation, while stocking density and basal area were positively correlated to precipitation. The study recommends continual retentions of trees on farm, further promoting of agroforestry interventions and sustainable utilization of woody plants in open and close canopy forests. 展开更多
关键词 water Basin Forest Disturbance Riparian Forests Rift Valley SAVANNAH
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Root distribution and influencing factors of dry-sowing and wet-growing cotton plants under different water conditions
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作者 DING Yu ZHANG Jianghui +4 位作者 BAI Yungang LIU Hongbo ZHENG Ming ZHAO Jinghua XIAO Jun 《排灌机械工程学报》 CSCD 北大核心 2023年第10期1073-1080,共8页
To study the effect of soil water and salt environment factors on the root growth of cotton under different moisture control,three different emergence water volumes(60,105,and 150 m^(3)/hm^(2)),two different frequenci... To study the effect of soil water and salt environment factors on the root growth of cotton under different moisture control,three different emergence water volumes(60,105,and 150 m^(3)/hm^(2)),two different frequencies(high frequency and low frequency)and one double film cover winter irrigation control treatment(CK:2250 m^(3)/hm^(2))were set up to analyze the spatial distribution patterns of soil water and salt environment and root density in dry sown and wet emerged cotton fields under diffe-rent moisture control conditions.The results show that the soil water content and water infiltration range gradually become larger with the increase of seedling water quantity,and the larger the seedling water quantity,the higher the soil water content.With the same seedling water quantity,the soil water content of the high-frequency(HF)treatment becomes obviously larger.The soil conductivity of each treatment tends to decrease gradually with the increase of seedling water and drip frequency,among which the distribution of soil conductivity of S6 treatment is closest to that of CK.With the increase in soil depth,the soil conductivity tends to increase first and then decrease.Compared with the low-frequency(LF)treatment,the high-frequency treatment shows a significantly deeper soil salt accumulation layer.The root length density(RLD)of cotton gradually increases with the amount of seedling water and the frequency of dripping.The soil layer of root distribution gradually deepens with the amount of seedling water in the vertical direction,and the RLD value in the horizontal direction is significantly greater in the mulched area than that in the bare area between films.This research can serve as a solid scientific foundation for the use of dry sowing and wet emergence techniques in cotton fields in southern Xinjiang. 展开更多
关键词 COTTON double film mulching dry sowing and wet germination moisture regulation water and salt distribution root distribution cotton double film mulching dry sowing and wet germination moisture regulation water and salt distribution root distribution
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Collaborative Efforts and Strategies for Cholera Outbreak Control in Garissa County, Kenya: Implementation of Water Quality Monitoring Interventions
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作者 Michael Habtu Mark Nanyingi +14 位作者 Ali A. Hassan Abdiwahid M. Noor Joel Mutyandia Muli Alan Mwika Julius Wekesa Ahmed Fidhow Diba Dulacha Landry Kabego Ishata Nannie Conteh Andre Arsene Bita Fouda Sonia Chene Aden H. Ibrahim Ahmed Nadhir Omar Martins C. Livinus Abdourahmane Diallo 《Journal of Water Resource and Protection》 CAS 2024年第2期123-139,共17页
A multi-faceted Case Area Targeted Intervention (CATI) approach emphasizing the integration of Water, Sanitation and Hygiene (WASH) interventions and Oral Cholera Vaccine (OCV) campaign was employed to respond to the ... A multi-faceted Case Area Targeted Intervention (CATI) approach emphasizing the integration of Water, Sanitation and Hygiene (WASH) interventions and Oral Cholera Vaccine (OCV) campaign was employed to respond to the outbreak of cholera in Garissa County. Drinking water sources in areas heavily impacted by cholera were systematically mapped and tested for microbiological quality. The quality assessment was carried out in April 2023 during an ongoing cholera outbreak in the county. A total of 109 samples were collected and tested for thermotolerant coliforms and other in situ parameters. The finding revealed that more than 87% of the samples did not meet the World Health Organization (WHO) standard for thermotolerant coliforms;and 30% had turbidity values above the recommended threshold values. None of the 109 samples had any traceable residual chlorine. Following these findings, the county government implemented the targeted interventions which resulted in a positive impact in the fight against cholera. The WHO supported key interventions which included capacity building in water quality monitoring and prepositioning of critical WASH commodities to the cholera affected areas. 展开更多
关键词 CHOLERA Drinking water Household water Treatment Kenya
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Design and Sizing of an Ecological Wastewater Treatment System in a School Environment: A Case Study of Ndiebene Gandiol 1 School
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作者 Falilou Coundoul Abdou Khafor Ndiaye +1 位作者 Abdoulaye Deme David de la Varga 《Journal of Water Resource and Protection》 CAS 2024年第1期41-57,共17页
The primary objective of this study was to design and size a sustainable sanitation solution for the Ndiebene Gandiol 1 school located in the eponymous commune in northern Senegal. Field investigations led to the coll... The primary objective of this study was to design and size a sustainable sanitation solution for the Ndiebene Gandiol 1 school located in the eponymous commune in northern Senegal. Field investigations led to the collection of wastewater samples. Their analysis revealed specific pollutant loads, including loads of BOD5 3.6966 kgO<sub>2</sub>/day and COD of 12.8775 kgO<sub>2</sub>/day, which were central to the design phase. Following a rigorous assessment of the existing sanitation infrastructure, constructed wetland (CWs) emerged as the most appropriate ecological solution. This system, valued for its ability to effectively remove contaminants, was tailored to the specific needs of the site. Consequently, the final design of the filter extends over 217.16 m<sup>2</sup>, divided into two cells of 108.58 m<sup>2</sup> each, with dimensions of 12.77 m in length and 8.5 m in width. The depth of the filtering medium is approximately 0.60 m, meeting the standards while ensuring maximized purification. Typha, an indigenous and prolific plant known for its purification abilities, was selected as the filtering agent. Concurrently, non-crushed gravel was chosen for its proven filtration capacity. This study is the result of a combination of scientific rigor and design expertise. It provides a holistic view of sanitation for Ndiebene Gandiol. The technical specifications and dimensions of the constructed wetland filter embody an approach that marries indepth analysis and practical application, all aimed at delivering an effective and long-lasting solution to the local sanitation challenges. By integrating precise scientific data with sanitation design expertise, this study delivers a holistic solution for Ndiebene Gandiol. The detailed dimensions and specifications of the constructed wetland filter reflect a methodology that combines meticulous analysis with practical adaptation, aiming to provide an effective and sustainable response to the challenges of rural and school sanitation in the northern region of Senegal. 展开更多
关键词 water Review Hydraulic Engineering water Treatment Agricultural Irrigation SANITATION Engineering Environment
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Influence of Topography on the Distribution and Structure of Woody Plants in the Senegalese Sahel (Sandy Ferlo)
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作者 Moustapha Bassimbe Sagna Aïssatou Ndong Thiam +5 位作者 Khoudia Niang Oumar Sarr Aly Diallo Sekouna Diatta Daouda Ngom Aliou Guissé 《American Journal of Plant Sciences》 CAS 2024年第1期14-28,共15页
This study describes the floristic composition and structure of a woody stand in the Senegalese Sahel, paying particular attention to the edaphic factors of its floristic composition. A stratified inventory considerin... This study describes the floristic composition and structure of a woody stand in the Senegalese Sahel, paying particular attention to the edaphic factors of its floristic composition. A stratified inventory considering the different relief units was adopted. Woody vegetation was surveyed using a dendrometric approach. The results obtained show that the flora is dominated by a few species adapted to drought, such as Balanites aegyptiaca (L.) Del., Calotropis procera Ait. and Boscia senegalensis (Pers.). The distribution of this flora and the structure of the ligneous plants are linked to the topography. In the lowlands, the flora is more diversified and the ligneous plants reach their optimum level of development compared with the higher relief areas. In the lowlands, there are a few woody species which, in the past, were indicative of better climatic conditions. These are Anogeissus leiocarpus (DC.), Commiphora africana (A. Rich.), Feretia apodanthera Del., Loeseneriella africana (A. Smith), Mitragyna inermis (Willd.) and Sclerocarya birrea (A. Rich). It is important that their reintroduction into reforestation projects takes account of their edaphic preference. 展开更多
关键词 Woody plants DISTRIBUTION TOPOGRAPHY Ferlo Senegal
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