2020-2021 Annual Stormwater Report and Inspections for the Water Line Upgrade Project.

As a species for ecological restoration in northern China, Tamarix ramosissima plays an important role in river protection, flood control, regional climate regulation, and landscape construction with vegetation. Two sampling sites were selected in the hillside and floodplain habitats along the Lanzhou City, and the xylems of T. ramosissima and potential water sources were collected, respectively. The Bayesian mixture model (MixSIAR) and soil water excess (SW-excess) were applied to analyze the relationship on different water pools and the utilization ratios of T. ramosissima to potential water sources in two habitats. The results showed that the slope and intercept of local meteoric water line (LMWL) in two habitats were smaller compared with the global meteoric water line (GMWL), which indicated the existence of drier climate and strong evaporation in the study area, especially in the hillside habitat. Except for the three months in hillside, the SW-excess of T. ramosissima were negative, which indicated that xylems of T. ramosissima are more depleted in δ2H than the soil water line. In growing seasons, the main water source in hillside habitat was deep soil water (80~150 cm) and the utilization ratio was 63 ± 17% for T. ramosissima, while the main water source in floodplain habitat was shallow soil water (0~30 cm), with a utilization ratio of 42.6 ± 19.2%, and the water sources were different in diverse months. T. ramosissima has a certain adaptation mechanism and water-use strategies in two habitats, and also an altered water uptake pattern in acquiring the more stable water. This study will provide a theoretical basis for plant water management in ecological environment protection in the Loess Plateau.

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Physical structure and water line spectrum predictions of the intermediate mass protostar OMC2-FIR4

Astronomy and Astrophysics ◽

10.1051/0004-6361/200911651 ◽

2009 ◽

Vol 506 (3) ◽

pp. 1229-1241 ◽

Cited By ~ 32

Author(s):

N. Crimier ◽

C. Ceccarelli ◽

B. Lefloch ◽

A. Faure

Keyword(s):

Physical Structure ◽

Line Spectrum ◽

Intermediate Mass ◽

Water Line

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A global meta-analysis reveals a significant offset in δ2H between plant water and its sources

10.5194/egusphere-egu21-12207 ◽

2021 ◽

Author(s):

Javier de la Casa ◽

Adrià Barbeta ◽

Asun Rodriguez-Uña ◽

Lisa Wingate ◽

Jérôme Ogeé ◽

...

Keyword(s):

Isotopic Composition ◽

Soil Water ◽

Meta Analysis ◽

Water Evaporation ◽

Source Water ◽

Plant Water ◽

Water Line ◽

Plant Source ◽

Sampling Campaign ◽

The Mean

&#160;Long-standing ecological theory establishes that the isotopic composition of the plant water reflects that of the root-accessed sources, at least in non-saline or non-xeric environments. However, a growing number of studies challenge this assumption by reporting plant-source offsets in water isotopic composition, for a wide range of ecosystems. We conducted a global meta-analysis to systematically quantify the magnitude of this plant-source offset in water isotopic composition and its potential explanatory factors. We compiled 108 studies reporting dual water isotopic composition (&#948;2H and &#948;18O) of plant and source water. From these studies, we extracted the &#948;2H and &#948;18O of both plant and source waters for 223 plant species from artic to tropical biomes. For each species and sampling campaign, within each study, we calculated the mean line conditioned excess (LC-excess), with the slope and intercept of the local meteoric water line, and the mean soil water line conditioned excess (SWL-excess), from the slope and intercept of the soil water evaporation line. For each study site and sampling campaign, we obtained land surface temperature and volumetric soil water from the ERA5 database. For each study species, we recorded the functional type, leaf habit and for those available wood density. We found, on average, a significantly negative SWL-excess: plant water was systematically more depleted in &#948;2H than soil water. In > 90% of the cases with significantly negative SWL-excess, we also found negative LC-excess values, meaning that access to sources alternative to soil water was unlikely to explain negative SWL-excess values.&#160;Calculated SWL-excess was affected by temperature and humidity: there were larger mismatches between plant and source water in isotopic composition in colder and wetter sites. Angiosperms, broadleaved and deciduous species exhibited more negative SWL-excess values than gymnosperms, narrow-leaved and evergreen species. Our results suggest that when using the dual isotopic approach, potential biases in the adscription of plant water sources are more likely in broadleaved forests in humid, and cold regions. Potential underlying mechanism for these isotopic mismatches will be discussed.&#160;

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Predicting the sound power and impact of a wastewater treatment plant

Water Science & Technology ◽

10.2166/wst.2001.0775 ◽

2001 ◽

Vol 44 (2-3) ◽

pp. 235-242 ◽

Cited By ~ 3

Author(s):

B. De heyder ◽

P. Ockier ◽

R. Jansen ◽

R. Huiberts

Keyword(s):

Wastewater Treatment ◽

Empirical Model ◽

Wastewater Treatment Plant ◽

Treatment Plant ◽

Empirical Models ◽

Sound Power ◽

Water Line ◽

Model Derivation ◽

Close Distance

Several process units at a wastewater treatment plant (WWTP) can produce a significant level of sound and thus induce sound nuisance for nearby residents. The risk for sound nuisance should be considered by making a prognosis of sound impact in an early project phase (planning, design). A prognosis requires information with respect to the sound characteristics of the different process units. This paper reports the development of empirical models for the sound power of relevant process units in the water line at Aquafin WWTPs. The used methodology for model derivation and validation allowed us to minimize the required number of measurements. Besides the methodology, the paper describes in detail the derivation and validation of the empirical model for the splashing water of screw pumps. Also the use of all the derived empirical models to determine the sound impact of a wastewater treatment plant at close distance is illustrated with a case-study.

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Global perspective of local meteoric water lines based on daily and monthly data: a consideration of climate types

10.22541/au.161606496.64265677/v1 ◽

2021 ◽

Author(s):

Yang Song ◽

Shengjie Wang ◽

Athanassios Argiriou ◽

Mingjun Zhang ◽

Yudong Shi

Keyword(s):

Least Squares ◽

Meteoric Water ◽

Major Axis ◽

Ordinary Least Squares ◽

Weighted Regression ◽

Precipitation Data ◽

Monthly Data ◽

Water Line ◽

Meteoric Water Line ◽

Event Based

The stable hydrogen and oxygen isotopes as well as their correlation in precipitation have been widely investigated for the understanding of various hydrological processes. Monthly precipitation data were usually recommended in order to establish a linear relationship between the stable hydrogen and oxygen isotope ratios (also known as local meteoric water lines or LMWL for a specific location); however, the LMWL based on daily (or event-based) precipitation data is usually different from that using monthly data. Based on 83 sampling stations across the world from 2000 to 2017, local meteoric water lines were calculated using daily (or event-based) precipitation data (n=9354) and corresponding monthly data (n=1895), respectively; multiple regression methods were used, including ordinary least squares, reduced major axis and major axis regressions as well as their precipitation-weighted counterparts. The global meteoric water line from daily data is δ2H = (7.72 ± 0.02) δ18O + (6.84 ± 0.15) (n=9354, r2=0.96) and from monthly data is δ2H = (7.81 ± 0.04) δ18O+(7.61 ± 0.32) (n=1895, r2=0.96). The stations used in this study were grouped into five climate types, according to the Köppen Climate classification. The precipitation-weighted regression may increase the long-term receptiveness of LMWL using daily-based (or event-based) samples, not only for arid regions, but also for cold regions. When only relatively short-term isotopic records in event-based precipitation samples are available, which is usual in modern hydrological studies, the weighted regression (especially precipitation weighted ordinary least squares regression, PWLSR) is helpful to create a respective local meteoric water line.

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Study on resistance and intact stability behavior of patrol boat using axe bow hull form to support surveillance activities in the Indonesia territorial sea

Istrazivanja i projektovanja za privredu ◽

10.5937/jaes0-29354 ◽

2021 ◽

Vol 19 (3) ◽

pp. 822-832

Author(s):

Aulia Windyandari ◽

Adi Yusim

Keyword(s):

Total Resistance ◽

Conservation Areas ◽

Water Line ◽

Stability Behavior ◽

Fishery Resources ◽

Stability Performance ◽

Intact Stability ◽

Primary Means ◽

Fisheries Conservation ◽

Principal Dimension

As a sovereign maritime country, Indonesia has an obligation to protect, maintain, and manage marine and fishery resources. Patrol boats as the primary means of monitoring marine and fishery resources are needed in response to several problems and threats that may occur, such as illegal fishing, destructive fishing, violations of zoning in fisheries conservation areas and others. Apart from having to be adequate on the number of units, the patrol boats must also have suitable technology to support pursuit operations and suppress violations. The main objective of this research is to investigate the total resistance and intact stability behavior of the developed axe bow hull geometry for the patrol boat hull. The preliminary design is started with the determination of the principal dimension of the patrol boat. Then the hull geometry configurations were made with the variation of the depth of bow and the water line spline type. In the case of the depth of bow, the bow with the additional depth of 30%, 40% and 50% of the draft was investigated. Otherwise, the water line spline type was configured as convex spline, concave spline and straight spline. According to the numerical analysis, the axe bow hull with the depth of bow of 30% and the straight spline type was presented the smallest total resistance performance. However, in the case of intact stability performance, all developed axe bow hull presented a similar righting moment lever arm (GZ curve). It is indicated that the total resistance of the axe bow hull is influenced by the depth of bow and water line spline type. Furthermore, those variables have a slight influence on intact stability performance.

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High temperature water line lists: comparison and validation

10.1117/12.724763 ◽

2006 ◽

Author(s):

S. A. Tashkun

Keyword(s):

High Temperature ◽

Water Line ◽

High Temperature Water ◽

Temperature Water

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Tracing groundwater salinization processes in coastal aquifers: a hydrogeochemical and isotopic approach in the Na-Cl brackish waters of northwestern Sardinia, Italy

Hydrology and Earth System Sciences ◽

10.5194/hess-17-2917-2013 ◽

2013 ◽

Vol 17 (7) ◽

pp. 2917-2928 ◽

Cited By ~ 37

Author(s):

G. Mongelli ◽

S. Monni ◽

G. Oggiano ◽

M. Paternoster ◽

R. Sinisi

Keyword(s):

Coastal Aquifers ◽

Meteoric Water ◽

Major Ions ◽

Mediterranean Islands ◽

Rock Interaction ◽

Water Line ◽

Brackish Waters ◽

Meteoric Water Line ◽

The Mediterranean ◽

Water Rock Interaction

Abstract. Throughout the Mediterranean, salinization threatens water quality, especially in coastal areas. This salinization is the result of concomitant processes related to both seawater intrusion and water–rock interaction, which in some cases are virtually indistinguishable. In the Nurra region of northwestern Sardinia, recent salinization related to marine water intrusion has been caused by aquifer exploitation. However, the geology of this region records a long history from the Palaeozoic to the Quaternary, and is structurally complex and comprises a wide variety of lithologies, including Triassic evaporites. Determining the origin of the saline component of the Jurassic and Triassic aquifers in the Nurra region may provide a useful and more general model for salinization processes in the Mediterranean area, where the occurrence of evaporitic rocks in coastal aquifers is a common feature. In addition, due to intensive human activity and recent climatic change, the Nurra has become vulnerable to desertification and, in common with other Mediterranean islands, surface water resources periodically suffer from severe shortages. With this in mind, we report new data regarding brackish and surface waters (outcrop and lake samples) of the Na-Cl type from the Nurra region, including major ions and selected trace elements (B, Br, I, and Sr), in addition to isotopic data including δ18O, δD in water, and δ34S and δ18O in dissolved SO4. To identify the origin of the salinity more precisely, we also analysed the mineralogical and isotopic composition of Triassic evaporites. The brackish waters have Cl contents of up to 2025 mg L−1 , and the ratios between dissolved ions and Cl, with the exception of the Br / Cl ratio, are not those expected on the basis of simple mixing between rainwater and seawater. The δ18O and δD data indicate that most of the waters fall between the regional meteoric water line and the global meteoric water line, supporting the conclusion that they are meteoric in origin. A significant consequence of the meteoric origin of the Na-Cl-type water studied here is that the Br / Cl ratio, extensively used to assess the origin of salinity in fresh water, should be used with care in carbonate aquifers that are near the coast. Overall, δ34S and δ18O levels in dissolved SO4 suggest that water–rock interaction is responsible for the Na-Cl brackish composition of the water hosted by the Jurassic and Triassic aquifers of the Nurra, and this is consistent with the geology and lithological features of the study area. Evaporite dissolution may also explain the high Cl content, as halite was detected within the gypsum deposits. Finally, these Na-Cl brackish waters are undersaturated with respect to the more soluble salts, implying that in a climate evolving toward semi-arid conditions, the salinization process could intensify dramatically in the near future.

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IV. Impact with a liquid surface studied by the aid of instantaneous photography. Paper II

Philosophical Transactions of the Royal Society of London. Series A, Containing Papers of a Mathematical or Physical Character ◽

10.1098/rsta.1900.0016 ◽

1900 ◽

Vol 194 (252-261) ◽

pp. 175-199 ◽

Cited By ~ 79

Keyword(s):

Liquid Surface ◽

Thin Glass ◽

Water Line ◽

Glass Vessel ◽

Camera Lens ◽

General Arrangement ◽

Set Up ◽

The Impact ◽

Rough Sphere ◽

Smooth Sphere

In a previous paper (‘Philosophical Transactions,’ A, 1897, vol. 189, p. 137) we have drawn attention to the fact that the disturbance set up in a liquid by the impact of a rough sphere falling into it, differs in a very remarkable manner from that which follows the entry of a smooth sphere. In the present paper we describe further experiments, made with the object of ascertaining the reason of this difference, and give the conclusions reached. It appeared desirable, in the first place, to take instantaneous photographs of the disturbed liquid below the water-line. These were easily obtained by letting the splash take place in an approximately parallel-sided thin glass vessel (an inverted clock-shade) illuminated from behind. The liquid surface when undisturbed was about level with the middle of the camera-lens, which was focussed for the sphere when under water. The general arrangement of the optical apparatus will be sufficiently understood from the accompanying cut (fig. 1). The method of timing the illumination was that already described ( loc. cit. ).

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