Irrigation Activities Research Articles

Indicator of Flood-Irrigated Crops From SMOS and SMAP Soil Moisture Products in Southern India

Spaceborne L-band data have the potential to monitor flooded and irrigated areas. However, further studies are needed to assess in real cases the impact of flood-irrigated crops on SMOS and SMAP surface soil moisture (SSM) data. This paper demonstrates the ability of SMOS/SMAP SSM retrievals to quantify the fraction of flood-irrigated area at the seasonal scale and at a 25 km resolution in the Telangana State in southern India. Over irrigated areas, both SMOS level 3 (L3) SSM and SMAP L3 enhanced SSM products present a bimodal annual cycle, with a peak of SSM during the monsoon (wet) season corresponding to rainfall and irrigation, and a peak during the dry season due to irrigation activities solely. The second peak is absent or has a very small amplitude in areas where rice represents a small fraction (typically below 5-10%). More importantly, the amplitude of the second SSM peak is significantly correlated to the rice cover fraction within 25×25 km <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> pixels (R=0.81 for SMOS and 0.77 for SMAP), showing its potential to assess crop fraction and hence the water used for irrigation. The SMOS/SMAP L3 SSM peak during the dry period occurs several months before the harvest, constituting an indicator for rice stocks at the end of the season. However the irrigation signature is absent from the SMAP level 4 SSM product derived from the assimilation of SMAP brightness temperatures in a land surface model, which indicates that the data assimilation scheme is inefficient to restitute irrigation information.

Effect of active irrigation using shock wave-enhanced emission photoacoustic streaming on dental pulp stem cell viability

Background: Shock wave-enhanced emission photoacoustic streaming (SWEEPS) is a novel irrigation activation method based on photoacoustic streaming. The aim of this study was to look into the impact of SWEEPS on the attachment and survival of dental pulp stem cells (DPSCs). Materials and Methods: In this in vitro study, 34 standardized root segments were randomly allocated into two groups: SWEEPS and the conventional conditioning group. After the irrigation human DPSCs were seeded on the internal walls of these samples, and the attachment and survival of 30 of them were assessed on different days. The remaining two samples were observed using a scanning electron microscope (SEM). Independent sample t-test, Mann–Whitney U-test, one-way ANOVA, Kruskal–Wallis, and two-way ANOVA were used for data analysis with the level of significance = 0.05. Results: The viability of DPSCs was significantly greater in the SWEEPS group in comparison with the conventional conditioning group (P = 0.029). Both groups have shown a significant increase in the viability of DPSCs over time (P = 0.0001, P = 0.003). SEM results have shown a smear layer-free surface with firmly attached DPSCs in the SWEEPS group. Conclusion: The results of this study indicated that active irrigation using SWEEPS could provide a superior surface in terms of viability and attachment of DPSCs compared to the conventional conditioning method.

Application of GIS technologies in the investigation of soil salinity

Soil salinization is the major problem affecting the productivity of irrigated lands. In Uzbekistan, irrigated area amounts to 4.5 million hectares or about 10% of Uzbekistan’s total area and almost 46.6% of these lands are affected by increasing salinity. The main reason for these conditions of irrigated land is the effect caused by natural factors (primary salinity) - inefficient natural drainage, saline groundwater, high evapotranspiration rates, and high capillary capacity of the soil. Moreover, human-induced processes (so-called “secondary salinity”), which lead to the enrichment of mineralization of groundwater. The objectives of this study iarethe soil salinity monitoring of irrigated lands and the mapping of the temporal and spatial distribution of salt-affected soils for the Arnasay district of Jizzakh province in Uzbekistan to support land management. Field data collected in 2017- 2018 was analyzed and based on the analysis soil map was developed. In the research area, based on these maps changes in soil salinity were identified. The results indicate that inefficient irrigation activities in the region would affect to the enrichment of salts in the top soils and reduce soil productivity. The GIS technologies are efficient tools for monitoring salt-affected lands.

Comparative Efficacy of Different Irrigant Activation Techniques for Irrigant Delivery Up to the Working Length of Mature Permanent Teeth: A Systematic Review and Meta-Analysis

This systematic review aims to establish whether various irrigant activation techniques (IATs) result in greater penetration of irrigant up to the working length. The MEDLINE, Scopus and Cochrane Library electronic databases were searched to determine the difference in irrigant penetration depth in the main canal following the use of manual dynamic activation (MDA), sonic irrigation (SI), passive ultrasonic irrigation (PUI), and apical negative pressure irrigation technique (ANP) in comparison with conventional needle irrigation technique (CNI) in mature permanent teeth. Meta-analysis was performed for straight canals as well as curved canals in addition to subgroup analyses for a) Individual IATs in comparison with CNI, b) Comparison of PUI v ANP and SI v ANP in the straight canals, c) comparison of different IATs performed in straight and curved canals. The outcome was presented as effect size: standardized mean difference (SMD) and percentage difference (% diff) of irrigant penetration up to the working length (WL) alongside 95% confidence intervals using chi-square analysis. Of the 840 records screened, 20 studies were included in the systematic review and 17 studies were included in the meta-analysis. It revealed IATs had significant improvement in irrigant delivery up to the WL in straight (% diff: 51.94%, 95% CI: 39.20-64.67%) and curved canals (SMD: 1.08, 95% CI: 0.64-1.52) over CNI. The subgroup analysis revealed ANP was the most effective and significant technique followed by PUI, SI and MDA techniques in straight canals (% diff: 91.70%, 95% CI: 75.63-107.77%) and curved canals (SMD: 1.45, 95% CI: 0.77-2.13). IATs improve irrigant penetration when compared to CNI technique. In both straight and curved canals, ANP is the most effective in delivering the irrigant up to the WL followed by PUI, SI and MDA techniques. Hence adaptation of recent IATs in routine endodontic practice is recommended. (EEJ-2022-03-036).

Natural-human driving factors of groundwater salinization in a long-term irrigation area

Salinization of groundwater is a major challenge for groundwater management in long-term irrigation areas, decoupling its complex influencing factors can provide insights for the sustainable development of irrigation areas. In this study, the natural-human driving factors of groundwater salinization in the Yinchuan Plain, a typical irrigated area, were identified using isotope analysis, information entropy, and self-organizing map. Results show that groundwater in the study area is seriously salinized with obvious spatial heterogeneity. Multiple natural conditions and frequent human activities complicate the salinization characteristics of groundwater. On this basis, four typical natural influence units of groundwater were identified, namely, an evaporation and upward leakage zone, a runoff zone, an evaporation zone, and a runoff and upward leakage zone. Information entropy was proposed to quantify the complexity of groundwater resulting from human activities: The complexity difference between densely populated areas and natural dominant areas is mainly reflected in Na+, SO42−, and Cl−. Multiple human-made drivers of complex water environment were further separated into three patterns by the SOM model: blockage-evaporation type, leakage-evaporation type, and irrigation type. The blockage of drainage ditches and obstruction of salt discharge has the highest impact on the salinization of groundwater, followed by irrigation activities and transportation losses. Water excessive stagnation caused by blockage or irrigation is the root cause of groundwater salinization in the irrigated area, and its impact is greater than that of the traditional understanding of groundwater level rise. Based on the evaluation of irrigation water quality, management initiatives for irrigated areas should prioritize dredging and maintaining a healthy soil and groundwater environment in tandem.

Comparison of apical extrusion of sodium hypochlorite in immature teeth after needle irrigation, ultrasonic irrigation, EDDY, Er:YAG, and diode lasers.

This study aimed to assess the apical extrusion of sodium hypochlorite in immature teeth caused by needle irrigation, ultrasonic irrigation, EDDY, Er:YAG, and diode lasers. Seventy-five human maxillary anterior teeth were selected. After the apical 3mm of the roots was resected, the canal lumen was enlarged with #2 to #5 Gates-Glidden burs. The teeth were fixed to the lid of a flat-sided clear plastic container, and the plastic containers were filled with 0.2% agarose gel containing 1mL of 0.1% m-cresol purple. Then, the specimens were allocated into five groups according to the irrigation activation techniques: needle irrigation, ultrasonic irrigation, EDDY, Er:YAG laser, and diode laser. The apical extrusion of sodium hypochlorite caused the color change in the gel. The containers were digitally photographed, and the percentage of pixels of irrigant extrusion (the color change) in each photograph was calculated. The diode laser group showed a significantly lower percentage of pixels than needle irrigation, EDDY, and Er:YAG laser (p < 0.05). The irrigant extrusion value of the ultrasonic irrigation group was significantly lower than that of the EDDY and Er:YAG laser groups (p < 0.05). There was no significant difference between the other groups (p > 0.05). All the groups caused irrigant extrusion in the immature teeth. The diode laser and ultrasonic irrigation caused less sodium hypochlorite extrusion than EDDY and Er:YAG laser. The needle irrigation showed more irrigant extrusion than the only diode laser group.

The effect of different irrigation and disinfection methods on post-operative pain in mandibular molars: a randomised clinical trial

BackgroundTo examine post-operative pain (PP) after conventional irrigation and sonic activation methods, with and without laser disinfection in mandibular molars.MethodsEighty patients with symptomatic apical periodontitis were included in this randomized clinical study. There were four study groups. In group 1, conventional irrigation only was applied. In group 2, a sonic irrigation activation system (EDDY (VDW, Munich, Germany)), was applied. In groups 3 and 4, irradiation with a 980-nm diode laser was performed, following irrigation with the conventional method and sonic irrigation activation system, respectively. The patients were instructed to record their PP and analgesic intake using a numerical rating scale 8, 24, 48 h and 7 days post-procedure. A chi-square test, Fisher’s exact chi-square test and Fisher–Freeman–Halton exact test were used to assess qualitative data. Inter-group and intra-group parameters were assessed using the Kruskal–Wallis test and Wilcoxon’s test at a significance level of p < 0.05.ResultsThere was no statistically significant difference among the groups in terms of age, sex, pre-operative pain, PP and analgesic intake (p > 0.05).ConclusionsThe use of sonic irrigation activation system in the final irrigation protocol and irradiation with the 980-nm diode laser did not significantly reduce PP levels and analgesic intake.

Evapotranspiration Characteristics of Different Oases and Effects of Human Activities on Evapotranspiration in Heihe River Basin

Evapotranspiration plays a decisive role in the whole oasis ecosystem and is an important factor to maintain the ecological stability of oases. To quantitatively analyze the evapotranspiration differences of oases at different scales and the expansion of urbanization, it is necessary to compare and discuss them at different time scales. In this study, the spatial and temporal characteristics of evapotranspiration of Zhangye Oasis, Jinta Oasis, and Ejina Oasis in the Heihe River basin were analyzed by using the remote sensing dataset of daily surface evapotranspiration of 100 m resolution from 2010 to 2016. The difference in evapotranspiration intensity in different oases was analyzed, and the influences of irrigation and urbanization expansion on evapotranspiration were discussed. The conclusion is as follows: Zhangye Oasis is the largest oasis in the area and, compared with other oases, due to the largest proportion of wetland and farmland in the underlying surface, the intensity of evapotranspiration is also the largest, reaching 650 mm/year on average. There is no obvious annual change; the range of evapotranspiration changes fluctuates between positive and negative 60 mm/year. Jinta Oasis began to decline after 2012; the evapotranspiration value dropped from 620 mm/tear to 560 mm/year, while Ejina Oasis showed a slight increase after 2014. In the irrigation stage, the evapotranspiration intensity increased significantly. Especially in the peak season of crop growth, the evapotranspiration after irrigation increased by 4 mm/day compared with that before irrigation. The evapotranspiration in urban and oasis areas is different in summer: compare that of 2010 with 2016—the evapotranspiration intensity of the expanding towns in the northeast direction decreased by about 50 mm/month, the northwest expanding towns decreased by about 110 mm/month. There was no obvious annual change in evapotranspiration in the urban area. With the expansion of urbanization, the evapotranspiration intensity in oases decreased. The results of this study provide some reference for the study of oasis irrigation activities and urbanization expansion.

Automatisasi Pompa Irigasi pada Sistem Irigasi Tetes Berbasis Mikrokontroller Arduino Uno

This drip irrigation system is a special water supply system in the root area.so that when carrying out irrigation activities, you can use water with a small discharge because it is only needed in the root area, in addition, technology greatly facilitates humans in various fields, one of which is agriculture. Therefore, with the internet of things (IOT) method, the drip irrigation system can be modified into automatic drip irrigation where the importance of this automatic drip irrigation system is in agriculture for sustainable agriculture in areas with limited water sources.The research method is experimental with a microcontroller as a control system, a relay as an LCD automatic switch as an output system and a sensor as a soil moisture reader. the results showed significant results where experiment 1, experiment 2, experiment 3, experiment 4, experiment 5 soil moisture sensor at 10-90% water percentage the pump status was on and off at 100% water percentage or soil saturated with water conditions.

Evaluation of Postoperative Pain Following Sonic and Ultrasonic Root Canal Irrigation Activation Protocols in Patients with Non-vital Teeth Associated with Apical Periodontitis (Randomized Clinical Trial

Aim: Evaluate the degree of postoperative pain in patients with necrotic teeth with symptomatic apical periodontitis in mandibular first molar teeth at 6, 12, 24, 48 and 72 hrs time interval after using different irrigation activation techniques in single-visit endodontic treatment. Material and Methods: Seventy-eight patients diagnosed with necrotic mandibular first molar with symptomatic apical periodontitis were randomly allocated into 1 of 3 separate groups (n=26); Navitip group (control), EndoUltra group, or Eddy group. After a single visit root canal treatment and a specific method of agitation, depending on each group, the patients were given a questionnaire on which the patient would mark the degree of pain in a scale from 0 to 10 at 6, 12, 24, 48, 72 hours and 7 days post-obturation. Data were statistically analyzed with a significance level of P≤0.05. Results: EndoUltra ultrasonic agitation and Eddy sonic agitation as a final irrigation protocol showed significantly lower pain values than the control group, but there was no significant difference in pain values between the experimental groups. Conclusion: There was significantly less pain associated with EndoUltra ultrasonic and Eddy sonic agitation compared to Navitip irrigation

The Effect of Different Irrigant Activation Methods on Postoperative Pain After Endodontic Retreatment

Aim: This study was designed to evaluate the effect of different irrigant activation methods on post operative pain after endodontic retreatment. Materials and Methods: seventy eight patients need non-surgical retreatment in mandibular first molar were involved in the study. The retreatment was performed in two visits, at first visit cases were randomly divided into three groups according to methods of irrigant activation after root canal retreatment with protaper next rotary ni-ti system. Group A (n=26) Root canals were irrigated using 2.6% sodium hypochlorite (NaOCl) with manual dynamic agitation using master cone Group B (n=26) Root canals were irrigated using 2.6% sodium hypochlorite (NaOCl) using ultrasonic machine (ultra-x) for 60 seconds. Group C (n=26) Root canals were irrigated using 2.6% sodium hypochlorite (NaOCl) with NaviTip (29-gauge 27 mm) with double side tip. At second visit after one week, obturation was performed using modified single cone technique ans access cavity was filled with coronal restoration. After two visits root canal treatment and a specific method of agitation, depending on each group, the patients were given a questionnaire on which the patient would mark the degree of pain in a scale from 0 to 10 at 6, 12, 24, 48 72 hrs and one week post-obturation. Data were statistically analyzed with a significance level of P ≤0.05. Results: At 6,12,24 hrs., there was significant difference between the groups in pain intensity where control group C (Navitip with side vented needle) showed more pain scores than in the intervention groups (Ultra X and manual dynamic agitation). On the other hand, at 48, 72 hours and 7 days post- operative, there was no statistically significant difference in pain among tested groups. Conclusion: Agitation of the irrigation is reliable safe to clinican and effective as final step irrigation protocol with successful management of postoperative pain in retreatment cases. The intensity of postoperative pain decreased with time regardless of final irrigation protocol used.

An in vitro scanning electron microscopic study: smear layer removal by chelat activation methods

Background: The process of mechanical root canal preparation creates smear layer. The smear layer can prevent the penetration of intracanal medicaments into dentinal tubules and influence the adaptation of filling materials to canal walls. The purpose of this study is to compare the smear layer removal ability of root canal irrigation methods with chelat solution. Materials and Methods: 45 extracted human premolar roots were selected and randomly divided into 3 groups (n=15) based on root canal irrigation methods with 17% EDTA solution: (1) Conventional needle irrigation, (2) Ultrasonic activation, (3) Sonic activation. The roots were prepared with Reciproc Blue 25 file and was removed smear layer by 3 different methods of irrigation. The study sample was then sectioned longitudinally with a diamond cutting disc, randomly selecting half of the root. After undergoing sample processing, the half roots were observed and evaluated for the presence of smear layer under a scanning electron microscope with a magnification of 1000 times according to Torabinejad (2003). Results: In cervical, the average smear layer score of the 3 study groups was not statistically significant (p&gt;0.05). In the middle, apical and over the root canal, the average smear layer score of the sonic activation method was lower than that of the other 2 groups. Conclusion: Sonic irrigation is more effective in removing smear layer than conventional needle irrigation and ultrasonic irrigation activation. Key words: smear layer, ultrasonic, sonic.

Uptake and Transport of Different Concentrations of PPCPs by Vegetables.

In many parts of the world, water resources are scarce or even extremely scarce, and the reuse of water resources has become mainstream in today's world. Many regions use treated wastewater for agricultural irrigation, aquaculture, and other activities. However, in recent years, wastewater has been found to contain large amounts of pharmaceuticals and personal care products (PPCPs). Therefore, there is a potential risk of PPCPs being transported in the environment and affecting human health. In this study, we compared the uptake, transport, and accumulation of 27 PPCPs in three types of sprouts (radish, buckwheat, and okra).The bioaccumulation of amantadine, diphenhydramine, chlorpheniramine maleate, sibutramine, hemosibutramine, chlorosibutramine, N-monomethyl sibutramine, N, N-desmethyl sibutramine, and carbamazepine was found to be significantly higher in plants grown for 12 days in media containing 0.5, 5.0, and 50.0 ng/mL PPCPs. With increasing concentration of PPCPs in the culture solution, the amount of PPCPs absorbed by plants and the degree of accumulation also showed an increasing trend. At the same time, it was demonstrated that there was an obvious uptake transfer phenomenon of PPCPs by plants, and the trend of uptake transfer became more and more obvious as the concentration of external environmental pollutants increased. In addition, amantadine, chlorpheniramine maleate, carbamazepine, N, N-desmethyl sibutramine, hemosibutramine, and chlorosibutramine showed more active translocation in some plants (TF > 1.0).

The efficiency of different irrigation activation techniques in the removal of calcium silicate-based endodontic sealer from artificially created groove.

This study evaluated the removal of a calcium silicate-based sealer (EndoSeal MTA) with needle irrigation (NI), passive ultrasonic irrigation (PUI), XP-endo Finisher (XPF) and EDDY. A total of 56 human mandibular premolars were instrumented up to size 40.04 taper. The roots were separated longitudinally, and grooves were prepared with an ultrasonic tip at one-half of each root canal. The grooves were covered with EndoSeal MTA and re-attached roots were investigated based on the activation techniques applied. The results showed that significantly more material (p < 0.05) was removed in the EDDY group compared to the NI, PUI and XPF groups in the apical region. In the coronal region, no significant difference was observed between EDDY, XPF and PUI (p > 0.05), whereas all the latter were significantly more effective than NI (p < 0.05). These findings show that the removal of EndoSeal MTA can be more effective with EDDY compared to XPF, PUI and NI in the apical region.

Evaluation of Dentinal Microcracks following Diode Laser- and Ultrasonic-Activated Removal of Bioceramic Material during Root Canal Retreatment.

This study is aimed at evaluating the use of microcomputed tomography (micro-CT) analysis and the dentinal microcrack formation following retreatment of bioceramic sealer employing adjunct laser-activated irrigation and ultrasonic-activated irrigation. Thirty sound human single-canal teeth (n = 30) obturated using the single-cone technique with bioceramic sealer were retreated using nickel-titanium (NiTi) rotary files. The sample was randomly divided into three equal groups: group 1, the control group, was not subjected to further treatment; group 2 underwent ultrasonic activation of irrigants; group 3 underwent active irrigation with a diode laser (980 nm wavelength). Using micro-CT, the teeth were scanned before and after retreatment protocols. Two calibrated experienced observers viewed the cross-sectional images and calculated the number of dentinal defects. The presence of any crack or craze line on the external root surface or internal canal wall was counted. Data were analyzed using Friedman's two-way analysis of variance and Fisher's exact test. Statistical significance was set at p < 0.05. A significant increase occurred in the number of cracks post retreatment protocols, specifically in the coronal and middle canal thirds, compared to pre- and postinstrumentation (p = 0.0001). However, ultrasonic- or laser-activated irrigation did not result in a significant increase in the number of cracks (p = 0.345). NiTi rotary root canal retreatment was associated with a significant increase in dentinal microcracks. However, employing ultrasonic- or laser-activated irrigation as adjunct retreatment techniques did not reveal a significant increase in dentinal microcracks within the roots.

Experimental Scrutinization on Treatment of Organic and Inorganic Effluents using Adsorption Process

Wastewater treatment has become one of the most significant sources for irrigation and other activities in arid and semi-arid countries. Many conventional methods deal with different organic and inorganic compounds of wastewater. One of the most common is using activated carbon through an adsorption process to treat wastewater. Adsorption is used when the contaminants present in wastewater are removed using activated carbon as an adsorbent. This paper examines the results of experiments on removing organic and inorganic compounds using activated carbon prepared from waste tyres, banana trunks, tea leaves and date seeds. Moreover, studies state that activated carbon has a strong affinity for binding organic substances, even at low concentrations. Thus, it has become the premier method for treating organic-laden wastewater. This paper reveals a method to deal with contaminants in wastewater which is very effective. Various experimental tests were carried out to determine the adsorption capacity of the different activated carbon, expressed as percentage removal of Chemical Oxygen Demand, Total Suspended Solid, and Total Dissolved Solid, and the effects of pH, contact time and dosage. The surface area of the adsorbent, pore volume and an isothermal graph of the adsorbent were determined using BET (Brunauer-Emmett-Teller) Surface Area. Waste tyres (WT), date seeds (DS), tea leaves (TL) and banana trunk (BT) have 1260, 1144.52, 163.8 and 115.4 m2/g surface area with 1.62, 0.656, 0.066088 and 0.4566 cm3 of total pore volume respectively indicating the use of waste tyres as an adsorbent. The moisture and ash content percentages were also determined and it was found that the above adsorbents have 2.6%, 6.4%, 7.4% and 9% moisture content, with 3.6%, 6.2%, 6.9% and 12% ash content respectively.

Heavy Metal Contamination Index, Metal Index and Polycyclic Aromatic Hydrocarbon Content of Ochani River in Ogoni, Rivers State, Nigeria

The Heavy metal Pollution Index (HPI), Metal Index (MI) and the Polycyclic Aromatic Hydrocarbon (PAH) contents of crude oil-polluted Ochani River in Ejamah-Ebubu community were investigated using physicochemical properties, Heavy Metal Analytic Method (AAS), GC-MS method and heavy metal pollution model. The results showed that Ochani River sampling station 2 (ORPS 2) had highest values of temperature, conductivity, turbidity, total solid (TS), total dissolved solid (TDS), Total Suspended Solid (TSS), Dissolved Oxygen (DO), Biochemical Oxygen Demand (BOD), Chemical Oxygen Demand (COD) and nitrates with values as (32oC, 260 µScm-1, 42NTU, 460 mg/L, 526 mg/L, 400 mg/L, 15 mg/L, 10 mg/L, 25 mg/L and 7.5 mg/L respectively) compared to Ochani River sampling station 1 (ORPS 1) with values as (30oC, 200 µScm-1, 38NTU, 400 mg/L, 500 mg/L, 380 mg/L, 13 mg/L, 9.0 mg/L, 22 mg/L and 6.8mg/L respectively). However, these values of ORPS 1and 2 were higher than the unpolluted water sample (UWS) and WHO standard limits. Heavy metals obtained in Ochani River were rankedas Fe &gt; Cu &gt;Pb&gt; Zn &gt; Cr &gt; Cd &gt;As. The values obtained from crude oil polluted water samples were highest when compared with the values obtained of the UWS and WHO standard limit. The heavy metal pollution index of Ochani River was calculated as 402.32 mg/L which was higher compared with the critical pollution index value of 100. The metal index obtained was 49.88mg/L showing that the water quality classified to be seriously polluted. The Polycyclic Aromatic Hydrocarbon (PAH) components present in Ochani River include fluorene, naphthalene, dibenzyl(a,h)anthracene, benzo(k)fluoranthene and benzo(a)pyrene. However, these values of PAH components obtained were highest in ORPS 2 compared to ORPS 1. No PAH content was detected in UWS. However, the values of PAH obtained in both ORPS 1 and 2 were higher compared with WHO standard limit. In conclusion, Ochani River which is an important river used for irrigation and domestic activities by the populace in that community, is highly polluted with heavy metals and carcinogenic PAHs. We therefore recommend that Ochani River is unsafe for drinking, domestic and agricultural activities of the community where it is sited.

Evaluation of reservoir sedimentation using bathymetry survey: a case study on Adebra night storage reservoir, Ethiopia

Reservoir sedimentation is a serious challenge that reduces reservoir life. Because it decreases the initial capacity of the reservoir and has an impact on drinking water supply, irrigation, and hydropower activities. Inadequate land activities and poor management techniques cause soil erosion and reduce reservoir storage capacity. As a result, accurate sediment estimation was assist in the adoption of sustainable land-use activities and best management practices that lead to effective reservoir operations. The main objective of this study was to evaluate the rate of sedimentation and remaining capacity of Adebra night storage reservoir (NSR) using a bathymetric survey and Arc-GIS 10.8. A comparison of original and current reservoir capacity was used to evaluate the quantity of sediment deposition in the reservoir. The latter was developed using Arc-GIS 10.8 and a bathymetry survey that was used to develop the TIN surface and evaluate reservoir volume. The Adebra NSR reservoir capacity was decreased by the accumulation of sedimentation from 36,902 m3 in 2012 to 27,722 m3 in 2020. The results of this study showed that the Adebra night storage reservoir had lost on average 24.8% of its capacity due to sedimentation, during 8 years of operation. The average deposition rate of sedimentation in Adebra NSR was estimated to be 1147.5 m3/year, with a loss rate of 3.1% per year. The value of sedimentation rates found in live storage of the reservoir area was 1147.5 m3/year. At the current time, the expected life of the night storage reservoir was reduced due to a lack of proper soil conservation practices in the reservoir catchment areas. In general, the study finding showed that the capacity of NSR was reduced by the accumulation of sedimentation year to year throughout the design period. Therefore, to improve the capacity of NSR should be planning and implementing different techniques of sediment control and removal, depending on the estimation of sediment production from watersheds of inlets and outlets of reservoirs.

Ocean acidification modifies behaviour of shelf seabed macrofauna: A laboratory study on two ecosystem engineers, Abra alba and Lanice conchilega

The feeding activity and burrow ventilation by benthic invertebrates importantly affect the biodiversity and functioning of seafloor sediments. Here we investigated how ocean acidification can modify these behavioural activities in two common and abundant macrofaunal ecosystem engineering species in temperate continental shelf communities: the white furrow shell Abra alba and the sand mason Lanice conchilega. Using time-lapse imagery and sediment porewater hydraulic signatures we show that both species adapt their behaviour in response to predicted future pH conditions (−0.3 units). During a three-week laboratory experiment, A. alba reduced the duration per feeding event when suspension and deposit feeding (by 86 and 53%, respectively), and almost completely ceased suspension feeding under reduced seawater pH in comparison to ambient seawater pH (pH ∼ 8.2). This behavioural change reduces the intake of low pH water during feeding and respiration. L. conchilega increased its piston-pumping frequency by 30 and 52%, respectively, after one and two weeks of exposure to future pH conditions (−0.3 units) relative to ambient conditions. This change in irrigation activity suggests higher metabolic demands under low seawater pH, and also extended low water column pH conditions deeper into the seafloor. Because the distribution of other populations depends on the physicochemical setting by our focal species, we argue that the demonstrated behavioural plasticity will likely have cascading effects on seafloor diversity and functioning, highlighting the complexity of how ocean acidification, and climate change in general, will affect seafloor ecology.

The Role of Irrigation Expansion on Historical Climate Change: Insights From CMIP6

AbstractTo produce food for a growing world population, irrigated areas have increased from approximately 0.63 million km2 of land in 1900 to 3.1 million km2 of land in 2005. Despite this massive expansion, irrigation is still overlooked in most state‐of‐the‐art Earth system models (ESMs) involved in the Coupled Model Intercomparison Project phase 6 (CMIP6). To our knowledge, only three CMIP6 models represent irrigation activities: CESM2, GISS‐E2‐1‐G, and NorESM2‐LM. Here, we investigate the role of irrigation on historical climate at global and regional scales by analyzing trends of key surface climate variables in CMIP6 simulations during 1900–2014. The three models including irrigation show distinct behavior from the 15 models without irrigation over intensively irrigated areas (i.e., &gt;50% of grid cell area is equipped by irrigation): both annual (months that correspond to monthly air temperature higher than 274 K) mean latent heat flux (LHF) and soil moisture increase over time, in contrast to the models without irrigation that show no trend or even a negative trend. The positive LHF trend over intensively irrigated areas in the irrigation‐on models is consistent with three satellite‐based LHF products. While annual (considering the warmest month in a year) warming trends are found in these regions for most of the no‐irrigation models, the increase in LHF induces a cooling trend for the models with irrigation, which was not confirmed by observational air temperature data sets. These findings, supported by satellite data, indicate the importance of improved representation of land management in the next generation of ESM.