The relationship between spatial patterns of macrobenthos community characteristics and environmental conditions（salinity, temperature, dissolved oxygen, organic matter content, sand, silt and clay） was investigated...The relationship between spatial patterns of macrobenthos community characteristics and environmental conditions（salinity, temperature, dissolved oxygen, organic matter content, sand, silt and clay） was investigated throughout the Gorgan Bay in June 2010. Principal components analysis（PCA） based on environmental data separated eastern and western stations. The maximum（4 500 ind./m2） and minimum（411 ind./m2） densities were observed at Stas 1 and 6, respectively. Polychaeta was the major group and Streblospio gynobranchiata was dominant species in the bay. According to Distance Based Linear Models results, macrofaunal total density was correlated with silt percentage and salinity and these two factors explaining 64% of the variability while macrofaunal community structure just correlated with salinity（22% total variation）. In general, western part of the bay showed the highest number of species and biodiversity while, the highest density was found at Sta. 1 and in the middle part of the bay. Furthermore, relationship between diversity indices and macrobenthic species with measured factors is also discussed. Our results confirm the effect of salinity as an important factor on distribution of macrobenthic fauna in south Caspian brackish waters.展开更多
The aim of this research is to identify the most suitable land for forestry, afforestation and rangeland management in Hamadan province. This research has been accomplished using Makhdoum＇s model. In this research 30...The aim of this research is to identify the most suitable land for forestry, afforestation and rangeland management in Hamadan province. This research has been accomplished using Makhdoum＇s model. In this research 30 digital data layers are used. The Geographic Information System （GIS） has been used as main tool and overlay method has been used to implement the mentioned model. The results of this research revealed that the extent of favorite areas for fifth grade forestry, favorite areas for fourth grade afforestation, and favorite areas for third grade and fourth grade range management in the studied area. Based on the results of this research, the studied area has limited potentials for forestry and afforestation activities. The obtained results of evaluation also showed that the rangelands of Hamadan province are extremely poor. Since the rangelands have a substantial role in preservation of soil and water, therefore it is necessary to take appropriate measures for better exploitation of rangelands.展开更多
We present an annotated checklist for a total 241 reptiles and 22 amphibians including 5 frogs, 9 toads, 7 newts and salamanders, 1 crocodile, 1 worm lizard, 148 lizards, 79 snakes and 12 turtles and tortoises, includ...We present an annotated checklist for a total 241 reptiles and 22 amphibians including 5 frogs, 9 toads, 7 newts and salamanders, 1 crocodile, 1 worm lizard, 148 lizards, 79 snakes and 12 turtles and tortoises, includes the most scientific literature up to August 2014 and also based on several field surveys conducted in different Provinces of Iran from 2009 to 2014. We present an up-to-dated checklist of reptiles and amphibians in Iran. We provide a comprehensive listing of taxonomy, names, distribution and conservation status of all amphibians and reptiles of Iran. This checklist includes all recognized named taxa, English names for classes, orders, families, species, subspecies along with Persian names for species, including indication of native and introduced species. For the first time we report two non-native introduced reptiles from natural habitats of Iran. Of the total 22 species of amphibians in Iran, 6（27.2%） are endemic and of the total 241 species of reptiles, 55（22.8%） are endemic. Of the 22 amphibians species in Iran, 3（13%） are Critically Endangered, 2（9%） are Vulnerable and of the 241 reptile species 3（1.2%） are Critically Endangered, 4（1.6%） are Endangered and 10（4.1%） are Vulnerable. Accordingly, this paper combines significant aspects of taxonomy, common names, conservation status and distribution of the Iranian herpetofauna.展开更多
The frequency and severity of extreme events associated with global change are both forecast to increase with a concomitant increase expected in perturbations and disruptions of fundamental processes at ecosystem, com...The frequency and severity of extreme events associated with global change are both forecast to increase with a concomitant increase expected in perturbations and disruptions of fundamental processes at ecosystem, community and population scales, with potentially catastrophic consequences. Extreme events should thus be viewed as ecosystem drivers, rather than as short term deviations from a perceived ＇norm＇. To illustrate this, we examined the impacts associated with the extraordinary weather pattern of the austral spring/summer of 2001/2002, and find that patterns of ocean-atmosphere interactions appear linked to a suite of extreme events in Antarctica and more widely across the Southern Hemisphere. In the Antarctic, the extreme events appear related to particular ecological impacts, including the substantial reduction in breeding success of Ade1ie penguins at sites in the Antarctic Peninsula as well as for Adelie penguin and snow petrel colonies in East Antarctica, and the creation of new benthic habitats associated with the disintegration of the Larsen B Ice Shelf. Other major impacts occurred in marine and terrestrial ecosystems at temperate and tropical latitudes. The suite of impacts demonstrates that ecological consequences of extreme events are manifested at fundamental levels in ecosystem processes and produce long-term, persistent effects relative to the short-term durations of the events. Changes in the rates of primary productivity, species mortality, community structure and inter-specific interactions, and changes in trophodynamics were observed as a consequence of the conditions during the 2001/2002 summer. Lasting potential consequences include reaching or exceeding tipping points, trophic cascades and regime shifts.展开更多
Background:Many species of owls(Strigidae) represent cryptic species and their taxonomic study is in flux.In recent years,two new species of owls of the genus Strix have been described from the Middle East by differen...Background:Many species of owls(Strigidae) represent cryptic species and their taxonomic study is in flux.In recent years,two new species of owls of the genus Strix have been described from the Middle East by different research teams.It has been suggested that one of these species,S.omanensis,is not a valid species but taxonomic compari?sons have been hampered by the lack of voucher specimens of S.omanensis,and the poor state of the holotype of S.butleri.Methods:Here we use new DNA sequence data to clarify the taxonomy and nomenclature of the S.butleri complex.We also report the capture of a single S.butleri sensu stricto in Mashhad,Iran.Results:A cytochrome b sequence of S.omanensis was found to be identical to that of the holotype of S.butleri,indicating that the name S.omanensis is best regarded as a junior synonym of S.butleri.The identity of the S.butleri captured in Mashhad,Iran,was confirmed using DNA sequence data.This represents a major(1300 km) range exten?sion of this species.Conclusions:The population discovered in Oman in 2013 and originally named ‘S.omanensis' actually represents the rediscovery of S.butleri,which was known from a single specimen and had not been recorded since 1878.The range of S.butleri extends into northeast Iran.Our study augments the body of evidence for the recognition of S.butleri and S.hadorami as separate species and highlights the importance of using multiple evidence to study cryptic owl species.展开更多
While hydropower is generally considered a clean energy source, it is important to recognize that their waste can still contribute to greenhouse gas emissions (GHG). The purpose of this study is to assess the carbon f...While hydropower is generally considered a clean energy source, it is important to recognize that their waste can still contribute to greenhouse gas emissions (GHG). The purpose of this study is to assess the carbon footprint associated with the waste sector throughout the operational phase of the Nam Theun 2 hydropower plant in Laos. Understanding the environmental impact of the waste sector is crucial for ensuring the plant’s sustainability. This study utilizes the theoretical estimation method recommended in the 2019 Refinement to the 2006 IPCC Guidelines for National Greenhouse Gas Inventories, as well as the Requirements for Specification with guidance at the organization level for quantification and reporting of GHG emissions and removals. We emphasize the significance of implementing sustainable waste management practices to reduce GHG emissions and minimize the environmental impact of hydropower operations. By conducting a comprehensive analysis, this paper also provides insights into the environmental implications of waste management in hydropower plants and identifies strategies to mitigate the carbon footprint in the waste sector. The findings contribute to a better understanding of the environmental sustainability of hydropower plants and provide valuable guidance for policymakers, energy producers, and environmental practitioners involved in hydropower plant design and operation.展开更多
This study focuses on determining the toxicological risks of urban waste from the city of Uvira, discharged into Lake Tanganyika, on the surrounding population. Volatile organic compounds were measured in a variety of...This study focuses on determining the toxicological risks of urban waste from the city of Uvira, discharged into Lake Tanganyika, on the surrounding population. Volatile organic compounds were measured in a variety of solid waste matrices, including inorganic micropollutants in wastewater and fish. The concentrations of Hg and Pb in the lake were found to be 1.21 and 1.42 μg/L respectively and between 0.83 to 18.36 μg/L of Hg and 8.25 to 670 μg/L of Pb, at the collector outlet. The presence of trace metallic elements, such as Cr, Co, Ni, Cu, Zn, As, Sb, Hg and Pb, were detected at high concentrations compared to the WHO standard. An ecotoxicology experiment herein on wastewater samples showed lethal pollutant concentrations of the order of 0.0055 mL/mL which killed at least 50% of fish (LC50), confirming the toxicity of the wastewater. These potentially harmful effluents also contain volatile organic compounds originating in high concentration from the pharmaceutical discharges of the general Uvira hospital, in particular: toluene, ethylbenzene, m-xylene/p-xylene, o-xylene and chloroform in higher concentrations compared to the norm. Other components such as benzene, bromodichloroethane and 1,1-dichloroethane were found to be present, but at a concentration below 0.05 ppb. A variety of trace organics can be suspected to be present as well.展开更多
Aquifer test methods have greatly improved in recent years with the advent of inverse analysis, derivative analysis, and diagnostic plots. Updated analyses of past aquifer tests allow for improved interpretations of t...Aquifer test methods have greatly improved in recent years with the advent of inverse analysis, derivative analysis, and diagnostic plots. Updated analyses of past aquifer tests allow for improved interpretations of the data to enhance the knowledge and the predictive capabilities of the flow system. This work thoroughly reanalyzes a series of pre- and post-hydraulic fracturing, single-well aquifer tests conducted in two crystalline rock wells in New Hampshire as part of an early 1970’s study. Previous analyses of the data had relied on older manual type-curve methods for predicting the possible effects of hydraulic fracturing. This work applies inverse analysis, derivative analysis, and diagnostic plots to reanalyze the 1970’s aquifer test data. Our results demonstrate that the aquifer tests were affected by changes in flow regimes, dewatering of the aquifer and discrete fractures, and changes due to well development. Increases in transmissivities are related to well development prior to hydraulic fracturing, propagation of a single, vertical fracture hydraulically connecting the two wells after stimulation and expansion of troughs of depression. After hydraulic fracturing, the estimated total yield of the individual wells increased by 2.5 times due to the hydraulic fracturing. However, the wells may be receiving water from the same source, and well interference may affect any significant increase in their combined yield. Our analyses demonstrate the value in applying inverse analysis, derivative analysis, and diagnostic plots over the conventional method of manual type-curve analysis. In addition, our improvement in the aquifer test interpretation of the 1970’s test data has implications for more reliable estimates of sustained well yields.展开更多
Physical development and planning of rural district is one of the most important environmental dimensions in rural areas. It is carried out by establishing spatial framework, in which economic and social activities ar...Physical development and planning of rural district is one of the most important environmental dimensions in rural areas. It is carried out by establishing spatial framework, in which economic and social activities are implemented successfully. In this regard, the current research was conducted for social, economic, and ecological development and planning in Behnemirrural district, using three major stages of planning process. These three stages included recognition, analysis, and integration. In the recognition stage, the natural, social, cultural, and physical features of the studied region were recognized. In the stage of analysis, facilities, issues, and their causes were analyzed by drawing causal analysis table. Then, issues were weighted and prioritized in terms of intensity, level of effect, and destruction importance. In the integration stage, the general goals were developed given the priority of issues. Then, operational goals and solutions were developed for each general goal and solutions were positioned on the map.展开更多
Introduction: Behaviour of many people in Mombele district is out of good hygiene practices related to waste management for reducing the environmental health risks. Thus, this study aimed to assess the practices relat...Introduction: Behaviour of many people in Mombele district is out of good hygiene practices related to waste management for reducing the environmental health risks. Thus, this study aimed to assess the practices related to insalubrity at Mombele district in Democratic Republic of Congo. Methods: To get results from this quantitative investigation, we used observation and survey as methods. Yet, a sample of 384 households helped to get results during the period from August 15<sup>th</sup> to October 15<sup>th</sup>, 2020. Results: The insalubrity is almost found everywhere. For respondents, it is seen through wild landfill (37.8%);wastes are thrown anywhere (59.4%);the main reason of this practice is the lack of dustbins (28.3%);the attitude towards insalubrity is positive (52.3%). There is a significant difference between the educational level, occupational categories, monthly incomes and the practice of throwing waste anywhere (p value Conclusion: Throughout the results, we say that the population from Mombele neighborhood hardly fears the insalubrity, because the majority of respondents find normal the practice of throwing wastes anywhere. This practice highlights that they do not fear the consequences that may affect the environment and the human health.展开更多
This study aims to analyze the effects of nutrients and predation by zooplankton on phytoplankton biomass (chlorophyll a) in a eutrophic reservoir in Brazil (Apipucos Reservoir, State of Pernambuco), through experimen...This study aims to analyze the effects of nutrients and predation by zooplankton on phytoplankton biomass (chlorophyll a) in a eutrophic reservoir in Brazil (Apipucos Reservoir, State of Pernambuco), through experiments in microcosms. For this, samples of water were placed in 1 L Erlenmeyer flasks and kept for seven days. Treatments included the addition of nutrients (nitrogen combined with phosphorus and isolated additions of nitrogen and phosphorus), with presence and absence of zooplankton and a control which contained the reservoir water without any manipulation. The addition of nutrients did not stimulate phytoplankton growth. However, zooplankton significantly decreased phytoplankton biomass in the treatments it was added to (p < 0.05). The results of this study showed that for the reservoir studied, predation by zooplankton is the most significant factor in the regulation of phytoplankton, contradicting several studies which show that phytoplankton biomass is more strongly controlled by nutrients (bottom-up control) than by predation (top-down control).展开更多
Efficient management of air quality requires a comprehensive emission inventory to support decision-making on air quality improvement.This article presents a comprehensive framework for detailed emission inventory dev...Efficient management of air quality requires a comprehensive emission inventory to support decision-making on air quality improvement.This article presents a comprehensive framework for detailed emission inventory development in cities with low-quality basic data,which examines the emission of primary criteria pollutants(CO,NO_(x),SO_(2),PM_(2.5),PM_(10),and VOC)from mobile sources,residential,commercial,and public services,fuel stations,transport terminals,energy conversion sections,and industries.This research was applied to Tabriz in Northwest Iran,one of the polluted medium-sized cities with a population of 1.77 million.Results show the city daily emission per capita is 569.8 g of CO,68.6 g of NO_(x),38.6 g of VOC,17.6 g of SO_(x),and 3.7 g of PM.Vehicular emissions accounted for 98%of CO,91%of VOCs,61%of NO_(x),and 56%of PM;meaning alternative policy strategies in vehicles would reduce emissions rapidly.Fifteen applicable and effective scenarios in transport and one concerning stationary sourceswere proposed and reduction potential of themwas evaluated.Effectiveness of the public transport improvement and replacement of old passenger cars were founded the key scenarios.These two alternatives decrease 14 and 2 tons of SO_(2) and 6797 and 2394 tons of NO_(x) annually with the cost of$99.5 MM and$366.5 MM,respectively.The findings of this study provides the choice of travel method by each citizen is a function of cost,speed,comfort and safety of travel;therefore,all the requirements of any scenarios must be fully considered in the implementation step.展开更多
Miscanthus grows well in some marginal and contaminated soils, and it has the potential to be used as a biofuel. Copper and cobalt are heavy metals that sometimes are present as contaminants in soils at concentrations...Miscanthus grows well in some marginal and contaminated soils, and it has the potential to be used as a biofuel. Copper and cobalt are heavy metals that sometimes are present as contaminants in soils at concentrations that may impact the safety of products that are harvested. Laboratory research has been conducted with Miscanthus sacchariflorus M. to investigate metal uptake of copper and cobalt because metal concentrations in the harvested parts of miscanthus are important for biofuel applications. The results show that the use of miscanthus for biofuel from soil contaminated by heavy metals depends mainly on the nature of contaminated metals: cobalt was detected only for highest treated concentration of metal and mainly in the roots. The highest concentration of copper was detected in the roots however this metal was detected in stems and leaves of miscanthus as well. Miscanthus biomass harvested from cobalt contaminated soil may be used for energy production because the harvested part accumulated only limited traces of the metal. The experimental results are in reasonable agreement with other results from the literature.展开更多
Sea-ice algae are a paramount feature of polar marine ecosystems and ice algal standing stocks are characterized by a high spatio-temporal variability. Traditional sampling techniques, e.g., ice coring, are laborinte...Sea-ice algae are a paramount feature of polar marine ecosystems and ice algal standing stocks are characterized by a high spatio-temporal variability. Traditional sampling techniques, e.g., ice coring, are laborintensive, spatially limited and invasive, thereby limiting our understanding of ice algal biomass variability patterns. Thishas consequences for quantifying ice-associated algal biomass distribution, primary production, and detecting responses to changing environmental conditions. Close-range under-ice optical remote sensing techniques have emerged as a capable alternative providing non-invasive estimates of ice algal biomass and its spatial variability. In this review we first summarize observational studies, using both classical and new methods that aim to capture biomass variability at multiple spatial scales and identify the environmental drivers. We introduce the complex multi-disciplinary nature of under-ice spectral radiation profiling techniquesand discuss relevant concepts of sea-ice radiative transfer and bio-optics. In addition, we tabulate and discuss advances and limitations of different statistical approaches used to correlate biomass and under-ice light spectral composition. We also explore theoretical and technical aspects of using Unmanned Underwater Vehicles （UUV）, and Hyperspectral Imaging （HI） technology in an under-ice remote sensing context. The review concludes with an outlook and way forward to combine platforms and optical sensors to quantify ice algal spatial variability and establish relationships with its environmental drivers.展开更多
Gamasyab River, which is the biggest river of Hamadan Province, is sourced from Karstic Springs in Nahavand Township Southern Mountainous Region and supplies a major part of water needs of the region. In this research...Gamasyab River, which is the biggest river of Hamadan Province, is sourced from Karstic Springs in Nahavand Township Southern Mountainous Region and supplies a major part of water needs of the region. In this research seasonal variation of water quality and also the degree of pollution related to Gamasyab River water have been assessed. First the general status of the river was studied and four sampling stations were determined. In this research, the quality of river water including Dissolved Oxygen （DO）, five days Biochemical Oxygen Demand （BOD）5, Chemical Oxygen Demand （COD）, Nitrate, phosphate, temperature, Total Hardness（TH）, Total Suspended Solid （TSS）, Total Dissolved Solid （TDS） and PH have been determined and assessed on a monthly basis within a five years period. The results were reported as seasonally and presented using statistical tables and graphs. These results showed that Nitrate concentration in Gamasyab River is strongly depending on distance from Gamasyab spring. By increasing the distance from Gamasyab spring, nitrate concentration increased. The amount of DO in the river water is stable in each station within the year. Air temperature changes have had no effect in the amount of DO. Therefore, it is recommended that the river pollution control plans be implemented more serious than before, non point source pollution related to agricultural activities be managed and prevent from pouring untreated rural wastewaters to the mentioned river.展开更多
基金financially supported by the Iranian National Institute for Oceanography(INIO)
文摘The relationship between spatial patterns of macrobenthos community characteristics and environmental conditions（salinity, temperature, dissolved oxygen, organic matter content, sand, silt and clay） was investigated throughout the Gorgan Bay in June 2010. Principal components analysis（PCA） based on environmental data separated eastern and western stations. The maximum（4 500 ind./m2） and minimum（411 ind./m2） densities were observed at Stas 1 and 6, respectively. Polychaeta was the major group and Streblospio gynobranchiata was dominant species in the bay. According to Distance Based Linear Models results, macrofaunal total density was correlated with silt percentage and salinity and these two factors explaining 64% of the variability while macrofaunal community structure just correlated with salinity（22% total variation）. In general, western part of the bay showed the highest number of species and biodiversity while, the highest density was found at Sta. 1 and in the middle part of the bay. Furthermore, relationship between diversity indices and macrobenthic species with measured factors is also discussed. Our results confirm the effect of salinity as an important factor on distribution of macrobenthic fauna in south Caspian brackish waters.
文摘The aim of this research is to identify the most suitable land for forestry, afforestation and rangeland management in Hamadan province. This research has been accomplished using Makhdoum＇s model. In this research 30 digital data layers are used. The Geographic Information System （GIS） has been used as main tool and overlay method has been used to implement the mentioned model. The results of this research revealed that the extent of favorite areas for fifth grade forestry, favorite areas for fourth grade afforestation, and favorite areas for third grade and fourth grade range management in the studied area. Based on the results of this research, the studied area has limited potentials for forestry and afforestation activities. The obtained results of evaluation also showed that the rangelands of Hamadan province are extremely poor. Since the rangelands have a substantial role in preservation of soil and water, therefore it is necessary to take appropriate measures for better exploitation of rangelands.
文摘We present an annotated checklist for a total 241 reptiles and 22 amphibians including 5 frogs, 9 toads, 7 newts and salamanders, 1 crocodile, 1 worm lizard, 148 lizards, 79 snakes and 12 turtles and tortoises, includes the most scientific literature up to August 2014 and also based on several field surveys conducted in different Provinces of Iran from 2009 to 2014. We present an up-to-dated checklist of reptiles and amphibians in Iran. We provide a comprehensive listing of taxonomy, names, distribution and conservation status of all amphibians and reptiles of Iran. This checklist includes all recognized named taxa, English names for classes, orders, families, species, subspecies along with Persian names for species, including indication of native and introduced species. For the first time we report two non-native introduced reptiles from natural habitats of Iran. Of the total 22 species of amphibians in Iran, 6（27.2%） are endemic and of the total 241 species of reptiles, 55（22.8%） are endemic. Of the 22 amphibians species in Iran, 3（13%） are Critically Endangered, 2（9%） are Vulnerable and of the 241 reptile species 3（1.2%） are Critically Endangered, 4（1.6%） are Endangered and 10（4.1%） are Vulnerable. Accordingly, this paper combines significant aspects of taxonomy, common names, conservation status and distribution of the Iranian herpetofauna.
基金supported by the Australian Antarctic Climate and Ecosystems Cooperative Research Centre
文摘The frequency and severity of extreme events associated with global change are both forecast to increase with a concomitant increase expected in perturbations and disruptions of fundamental processes at ecosystem, community and population scales, with potentially catastrophic consequences. Extreme events should thus be viewed as ecosystem drivers, rather than as short term deviations from a perceived ＇norm＇. To illustrate this, we examined the impacts associated with the extraordinary weather pattern of the austral spring/summer of 2001/2002, and find that patterns of ocean-atmosphere interactions appear linked to a suite of extreme events in Antarctica and more widely across the Southern Hemisphere. In the Antarctic, the extreme events appear related to particular ecological impacts, including the substantial reduction in breeding success of Ade1ie penguins at sites in the Antarctic Peninsula as well as for Adelie penguin and snow petrel colonies in East Antarctica, and the creation of new benthic habitats associated with the disintegration of the Larsen B Ice Shelf. Other major impacts occurred in marine and terrestrial ecosystems at temperate and tropical latitudes. The suite of impacts demonstrates that ecological consequences of extreme events are manifested at fundamental levels in ecosystem processes and produce long-term, persistent effects relative to the short-term durations of the events. Changes in the rates of primary productivity, species mortality, community structure and inter-specific interactions, and changes in trophodynamics were observed as a consequence of the conditions during the 2001/2002 summer. Lasting potential consequences include reaching or exceeding tipping points, trophic cascades and regime shifts.
基金financed and supported by The Sound Approach.It forms part of a broader Omani Owl conservation project conducted as a collaboration between The Sound Approach,Bird Life International and the Environment Society of Omanthe Omani Ministry of Social Development for approving this collaborationthe Ministry of Environment and Climatic Affairs for granting us permission for fieldwork and to take genetic samples from a wild Omani Owl(permit nr 5/2015)
文摘Background:Many species of owls(Strigidae) represent cryptic species and their taxonomic study is in flux.In recent years,two new species of owls of the genus Strix have been described from the Middle East by different research teams.It has been suggested that one of these species,S.omanensis,is not a valid species but taxonomic compari?sons have been hampered by the lack of voucher specimens of S.omanensis,and the poor state of the holotype of S.butleri.Methods:Here we use new DNA sequence data to clarify the taxonomy and nomenclature of the S.butleri complex.We also report the capture of a single S.butleri sensu stricto in Mashhad,Iran.Results:A cytochrome b sequence of S.omanensis was found to be identical to that of the holotype of S.butleri,indicating that the name S.omanensis is best regarded as a junior synonym of S.butleri.The identity of the S.butleri captured in Mashhad,Iran,was confirmed using DNA sequence data.This represents a major(1300 km) range exten?sion of this species.Conclusions:The population discovered in Oman in 2013 and originally named ‘S.omanensis' actually represents the rediscovery of S.butleri,which was known from a single specimen and had not been recorded since 1878.The range of S.butleri extends into northeast Iran.Our study augments the body of evidence for the recognition of S.butleri and S.hadorami as separate species and highlights the importance of using multiple evidence to study cryptic owl species.
文摘While hydropower is generally considered a clean energy source, it is important to recognize that their waste can still contribute to greenhouse gas emissions (GHG). The purpose of this study is to assess the carbon footprint associated with the waste sector throughout the operational phase of the Nam Theun 2 hydropower plant in Laos. Understanding the environmental impact of the waste sector is crucial for ensuring the plant’s sustainability. This study utilizes the theoretical estimation method recommended in the 2019 Refinement to the 2006 IPCC Guidelines for National Greenhouse Gas Inventories, as well as the Requirements for Specification with guidance at the organization level for quantification and reporting of GHG emissions and removals. We emphasize the significance of implementing sustainable waste management practices to reduce GHG emissions and minimize the environmental impact of hydropower operations. By conducting a comprehensive analysis, this paper also provides insights into the environmental implications of waste management in hydropower plants and identifies strategies to mitigate the carbon footprint in the waste sector. The findings contribute to a better understanding of the environmental sustainability of hydropower plants and provide valuable guidance for policymakers, energy producers, and environmental practitioners involved in hydropower plant design and operation.
文摘This study focuses on determining the toxicological risks of urban waste from the city of Uvira, discharged into Lake Tanganyika, on the surrounding population. Volatile organic compounds were measured in a variety of solid waste matrices, including inorganic micropollutants in wastewater and fish. The concentrations of Hg and Pb in the lake were found to be 1.21 and 1.42 μg/L respectively and between 0.83 to 18.36 μg/L of Hg and 8.25 to 670 μg/L of Pb, at the collector outlet. The presence of trace metallic elements, such as Cr, Co, Ni, Cu, Zn, As, Sb, Hg and Pb, were detected at high concentrations compared to the WHO standard. An ecotoxicology experiment herein on wastewater samples showed lethal pollutant concentrations of the order of 0.0055 mL/mL which killed at least 50% of fish (LC50), confirming the toxicity of the wastewater. These potentially harmful effluents also contain volatile organic compounds originating in high concentration from the pharmaceutical discharges of the general Uvira hospital, in particular: toluene, ethylbenzene, m-xylene/p-xylene, o-xylene and chloroform in higher concentrations compared to the norm. Other components such as benzene, bromodichloroethane and 1,1-dichloroethane were found to be present, but at a concentration below 0.05 ppb. A variety of trace organics can be suspected to be present as well.
文摘Aquifer test methods have greatly improved in recent years with the advent of inverse analysis, derivative analysis, and diagnostic plots. Updated analyses of past aquifer tests allow for improved interpretations of the data to enhance the knowledge and the predictive capabilities of the flow system. This work thoroughly reanalyzes a series of pre- and post-hydraulic fracturing, single-well aquifer tests conducted in two crystalline rock wells in New Hampshire as part of an early 1970’s study. Previous analyses of the data had relied on older manual type-curve methods for predicting the possible effects of hydraulic fracturing. This work applies inverse analysis, derivative analysis, and diagnostic plots to reanalyze the 1970’s aquifer test data. Our results demonstrate that the aquifer tests were affected by changes in flow regimes, dewatering of the aquifer and discrete fractures, and changes due to well development. Increases in transmissivities are related to well development prior to hydraulic fracturing, propagation of a single, vertical fracture hydraulically connecting the two wells after stimulation and expansion of troughs of depression. After hydraulic fracturing, the estimated total yield of the individual wells increased by 2.5 times due to the hydraulic fracturing. However, the wells may be receiving water from the same source, and well interference may affect any significant increase in their combined yield. Our analyses demonstrate the value in applying inverse analysis, derivative analysis, and diagnostic plots over the conventional method of manual type-curve analysis. In addition, our improvement in the aquifer test interpretation of the 1970’s test data has implications for more reliable estimates of sustained well yields.
文摘Physical development and planning of rural district is one of the most important environmental dimensions in rural areas. It is carried out by establishing spatial framework, in which economic and social activities are implemented successfully. In this regard, the current research was conducted for social, economic, and ecological development and planning in Behnemirrural district, using three major stages of planning process. These three stages included recognition, analysis, and integration. In the recognition stage, the natural, social, cultural, and physical features of the studied region were recognized. In the stage of analysis, facilities, issues, and their causes were analyzed by drawing causal analysis table. Then, issues were weighted and prioritized in terms of intensity, level of effect, and destruction importance. In the integration stage, the general goals were developed given the priority of issues. Then, operational goals and solutions were developed for each general goal and solutions were positioned on the map.
文摘Introduction: Behaviour of many people in Mombele district is out of good hygiene practices related to waste management for reducing the environmental health risks. Thus, this study aimed to assess the practices related to insalubrity at Mombele district in Democratic Republic of Congo. Methods: To get results from this quantitative investigation, we used observation and survey as methods. Yet, a sample of 384 households helped to get results during the period from August 15<sup>th</sup> to October 15<sup>th</sup>, 2020. Results: The insalubrity is almost found everywhere. For respondents, it is seen through wild landfill (37.8%);wastes are thrown anywhere (59.4%);the main reason of this practice is the lack of dustbins (28.3%);the attitude towards insalubrity is positive (52.3%). There is a significant difference between the educational level, occupational categories, monthly incomes and the practice of throwing waste anywhere (p value Conclusion: Throughout the results, we say that the population from Mombele neighborhood hardly fears the insalubrity, because the majority of respondents find normal the practice of throwing wastes anywhere. This practice highlights that they do not fear the consequences that may affect the environment and the human health.
基金supported by grants from CNPq(Brazil-ian Council for Research and Development(302068/2011-2).
文摘This study aims to analyze the effects of nutrients and predation by zooplankton on phytoplankton biomass (chlorophyll a) in a eutrophic reservoir in Brazil (Apipucos Reservoir, State of Pernambuco), through experiments in microcosms. For this, samples of water were placed in 1 L Erlenmeyer flasks and kept for seven days. Treatments included the addition of nutrients (nitrogen combined with phosphorus and isolated additions of nitrogen and phosphorus), with presence and absence of zooplankton and a control which contained the reservoir water without any manipulation. The addition of nutrients did not stimulate phytoplankton growth. However, zooplankton significantly decreased phytoplankton biomass in the treatments it was added to (p < 0.05). The results of this study showed that for the reservoir studied, predation by zooplankton is the most significant factor in the regulation of phytoplankton, contradicting several studies which show that phytoplankton biomass is more strongly controlled by nutrients (bottom-up control) than by predation (top-down control).
文摘Efficient management of air quality requires a comprehensive emission inventory to support decision-making on air quality improvement.This article presents a comprehensive framework for detailed emission inventory development in cities with low-quality basic data,which examines the emission of primary criteria pollutants(CO,NO_(x),SO_(2),PM_(2.5),PM_(10),and VOC)from mobile sources,residential,commercial,and public services,fuel stations,transport terminals,energy conversion sections,and industries.This research was applied to Tabriz in Northwest Iran,one of the polluted medium-sized cities with a population of 1.77 million.Results show the city daily emission per capita is 569.8 g of CO,68.6 g of NO_(x),38.6 g of VOC,17.6 g of SO_(x),and 3.7 g of PM.Vehicular emissions accounted for 98%of CO,91%of VOCs,61%of NO_(x),and 56%of PM;meaning alternative policy strategies in vehicles would reduce emissions rapidly.Fifteen applicable and effective scenarios in transport and one concerning stationary sourceswere proposed and reduction potential of themwas evaluated.Effectiveness of the public transport improvement and replacement of old passenger cars were founded the key scenarios.These two alternatives decrease 14 and 2 tons of SO_(2) and 6797 and 2394 tons of NO_(x) annually with the cost of$99.5 MM and$366.5 MM,respectively.The findings of this study provides the choice of travel method by each citizen is a function of cost,speed,comfort and safety of travel;therefore,all the requirements of any scenarios must be fully considered in the implementation step.
文摘Miscanthus grows well in some marginal and contaminated soils, and it has the potential to be used as a biofuel. Copper and cobalt are heavy metals that sometimes are present as contaminants in soils at concentrations that may impact the safety of products that are harvested. Laboratory research has been conducted with Miscanthus sacchariflorus M. to investigate metal uptake of copper and cobalt because metal concentrations in the harvested parts of miscanthus are important for biofuel applications. The results show that the use of miscanthus for biofuel from soil contaminated by heavy metals depends mainly on the nature of contaminated metals: cobalt was detected only for highest treated concentration of metal and mainly in the roots. The highest concentration of copper was detected in the roots however this metal was detected in stems and leaves of miscanthus as well. Miscanthus biomass harvested from cobalt contaminated soil may be used for energy production because the harvested part accumulated only limited traces of the metal. The experimental results are in reasonable agreement with other results from the literature.
基金supported by the Australian Research Council’s Special Research Initiative for Antarctic Gateway Partnership (Project ID SR140300001)EC was supported by the Antarctic Gateway Partnership+3 种基金the University of Tasmania’s Institute for Marine and Ph.D. programKMMs contribution to this work was supported by the Australian Governments Cooperative Research Centres Program through the Antarctic Climate and Ecosystems Cooperative Research Centre, through Australian Antarctic Science project #4298 and through a fellowship at the Hanse-Wissenschaftskolleg (Delmenhorst, Germany)LCLH’s contribution to the work was supported by AUFF (Aarhus University Research Foundation) grant nr. 20858. (Delmenhorst, Germany)LCLH’s contribution to the work was supported by AUFF (Aarhus University Research Foundation) grant nr. 20858
文摘Sea-ice algae are a paramount feature of polar marine ecosystems and ice algal standing stocks are characterized by a high spatio-temporal variability. Traditional sampling techniques, e.g., ice coring, are laborintensive, spatially limited and invasive, thereby limiting our understanding of ice algal biomass variability patterns. Thishas consequences for quantifying ice-associated algal biomass distribution, primary production, and detecting responses to changing environmental conditions. Close-range under-ice optical remote sensing techniques have emerged as a capable alternative providing non-invasive estimates of ice algal biomass and its spatial variability. In this review we first summarize observational studies, using both classical and new methods that aim to capture biomass variability at multiple spatial scales and identify the environmental drivers. We introduce the complex multi-disciplinary nature of under-ice spectral radiation profiling techniquesand discuss relevant concepts of sea-ice radiative transfer and bio-optics. In addition, we tabulate and discuss advances and limitations of different statistical approaches used to correlate biomass and under-ice light spectral composition. We also explore theoretical and technical aspects of using Unmanned Underwater Vehicles （UUV）, and Hyperspectral Imaging （HI） technology in an under-ice remote sensing context. The review concludes with an outlook and way forward to combine platforms and optical sensors to quantify ice algal spatial variability and establish relationships with its environmental drivers.
文摘Gamasyab River, which is the biggest river of Hamadan Province, is sourced from Karstic Springs in Nahavand Township Southern Mountainous Region and supplies a major part of water needs of the region. In this research seasonal variation of water quality and also the degree of pollution related to Gamasyab River water have been assessed. First the general status of the river was studied and four sampling stations were determined. In this research, the quality of river water including Dissolved Oxygen （DO）, five days Biochemical Oxygen Demand （BOD）5, Chemical Oxygen Demand （COD）, Nitrate, phosphate, temperature, Total Hardness（TH）, Total Suspended Solid （TSS）, Total Dissolved Solid （TDS） and PH have been determined and assessed on a monthly basis within a five years period. The results were reported as seasonally and presented using statistical tables and graphs. These results showed that Nitrate concentration in Gamasyab River is strongly depending on distance from Gamasyab spring. By increasing the distance from Gamasyab spring, nitrate concentration increased. The amount of DO in the river water is stable in each station within the year. Air temperature changes have had no effect in the amount of DO. Therefore, it is recommended that the river pollution control plans be implemented more serious than before, non point source pollution related to agricultural activities be managed and prevent from pouring untreated rural wastewaters to the mentioned river.
