Projections of future urban land change are essential for a range of sustainability assessments,including those related to biodiversity loss,carbon emissions,and agricultural land conversion.However,to what extent and...Projections of future urban land change are essential for a range of sustainability assessments,including those related to biodiversity loss,carbon emissions,and agricultural land conversion.However,to what extent and where current projections agree or disagree remains unknown.Here,we systematically compare existing global projections that are consistent with the Shared Socioeconomic Pathways.We find that the total global urban land area is expected to increase by 112%between 2020 and 2100(averaged across all projections),with a coefficient of variation of 0.81.This variation is mostly caused by the selection of the underlying drivers that are included in the different models.Regionally,the highest average growth rates are found in sub-Saharan Africa(+679%to+730%),while this region also has the highest variation across projections(coefficient of variation ranging from 2.02 to 2.18).When ranking scenarios within a study from the highest to the lowest projected increase in urban land,rankings are relatively similar for regions in the Global North,but not for regions in the Global South.The large disagreement across projections can lead to high uncertainties in assessments of future urban land change impacts,which can undermine the effectiveness of long-term planning,policymaking,and resource management decisions.展开更多
In Bangladesh,20 gas fields out of 28 produced 709.11 billion cubic feet(Bcf)through 112 wells against a vast amount of demand in the financial year 2021e22.Therefore,more gas fields need to be explored in the most pr...In Bangladesh,20 gas fields out of 28 produced 709.11 billion cubic feet(Bcf)through 112 wells against a vast amount of demand in the financial year 2021e22.Therefore,more gas fields need to be explored in the most prospective offshore part of Bangladesh.In this study,we have attempted to estimate a prospecting natural gas reserve in the Eastern Fold Belt(Block 18)consisting of Teknaf,Coral Dip,and St Martin Island as well as to develop a production view for the future.Based on the prerequisite research data collected from Petrobangla,Monte Carlo simulations were used to estimate the reserve values as Gas Initially In Place(GIIP)and Recoverable Gas Initially In Place(RGIIP)by Petroleum Engineering(PE)Essential software(version 2017.4).The results show that the estimated GIIP and RGIIP are 6145.88 billion standard cubic feet(Bscf)and 4745.5 Bscf,respectively which are quite close to the previous study.The total estimated proven natural gas of the study is 2064.4 Bcf.展开更多
OBJECTIVE: To compare the effects of a Chinese herbal suppository(Jianpi suppository) and Western Medicine(mesalazine) on hemorheology and CD62p in patients with ulcerative colitis(UC).METHODS: In a randomized trial, ...OBJECTIVE: To compare the effects of a Chinese herbal suppository(Jianpi suppository) and Western Medicine(mesalazine) on hemorheology and CD62p in patients with ulcerative colitis(UC).METHODS: In a randomized trial, 120 mild to moderate UC patients were randomly divided into two equal groups. The Jianpi suppository group used Chinese herbal suppository rectally, while the mesalazine group was treated with mesalazine tablets orally. Two 15-day courses of treatment were carried out in both groups. Changes in the hemorheology and CD62p indices in patients were observed.RESULTS: The hemorheology and CD62p indices in the Jianpi suppository group decreased significantly more than those of the mesalazine group.CONCLUSION: Jianpi suppository is effective in improving the hypercoagulability of UC patients, and therefore may be worth using in clinical practice.展开更多
Aquaculture ponds are dominant features of the landscape in the coastal zone of China.Generally,aquaculture ponds are drained during the non-culture period in winter.However,the effects of such drainage on the product...Aquaculture ponds are dominant features of the landscape in the coastal zone of China.Generally,aquaculture ponds are drained during the non-culture period in winter.However,the effects of such drainage on the production and flux of greenhouse gases（GHGs）from aquaculture ponds are largely unknown.In the present study,field-based research was performed to compare the GHG fluxes between one drained pond（DP,with a water depth of 0.05 m）and one undrained pond（UDP,with a water depth of 1.16 m）during one winter in the Min River estuary of southeast China.Over the entire study period,the mean CO2flux in the DP was（0.75±0.12）mmol/（m^2·hr）,which was significantly higher than that in the UDP of（-0.49±0.09）mmol/（m^2·hr）（p0.01）.This indicates that drainage drastically transforms aquaculture ponds from a net sink to a net source of CO2in winter.Mean CH4and N2O emissions were significantly higher in the DP compared to those in the UDP（CH4=（0.66±0.31）vs.（0.07±0.06）mmol/（m^2·hr）and N2O=（19.54±2.08）vs.（0.01±0.04）μmol/（m^2·hr））（p〈0.01）,suggesting that drainage would also significantly enhance CH4and N2O emissions.Changes in environmental variables（including sediment temperature,p H,salinity,redox status,and water depth）contributed significantly to the enhanced GHG emissions following pond drainage.Furthermore,analysis of the sustained-flux global warming and cooling potentials indicated that the combined global warming potentials of the GHG fluxes were significantly higher in the DP than in the UDP（p〈0.01）,with values of739.18 and 26.46 mg CO2-eq/（m^2·hr）,respectively.Our findings suggested that drainage of aquaculture ponds can increase the emissions of potent GHGs from the coastal zone of China to the atmosphere during winter,further aggravating the problem of global warming.展开更多
Multifractal detrended fluctuation analysis （MF-DFA） is a relatively new method of multifractal analysis. It is extended from detrended fluctuation analysis （DFA）, which was developed for detecting the long-range ...Multifractal detrended fluctuation analysis （MF-DFA） is a relatively new method of multifractal analysis. It is extended from detrended fluctuation analysis （DFA）, which was developed for detecting the long-range correlation and the fractal properties in stationary and non-stationary time series. Although MF-DFA has become a widely used method, some relationships among the exponents established in the original paper seem to be incorrect under the general situation. In this paper, we theoretically and experimentally demonstrate the invalidity of the expression r（q） = qh（q） - 1 stipulating the relationship between the multifractal exponent T（q） and the generalized Hurst exponent h（q）. As a replacement, a general relationship is established on the basis of the universal multifractal formalism for the stationary series as .t-（q） = qh（q） - qH - 1, where H is the nonconservation parameter in the universal multifractal formalism. The singular spectra, a and f（a）, are also derived according to this new relationship.展开更多
Geodiversity refers to the diversity(or variety, range) of geological(rocks,minerals,fossils),geomorphological (landform) and soil features,and their assemblages,relationships,processes,properties, interpretations and...Geodiversity refers to the diversity(or variety, range) of geological(rocks,minerals,fossils),geomorphological (landform) and soil features,and their assemblages,relationships,processes,properties, interpretations and systems.Despite there is a limited area of 1108 km^2,Hong Kong has a remarkably rich geodiversity that includes diversified geology, landforms,and assemblages of associated features and processes.Some geological features can even展开更多
Effects of earthworm casts on soil nutrient dynamics and their responses to changing moisture availability in subtropical ecosystems remain poorly understood.This study aimed to examine short-term carbon(C)and nitroge...Effects of earthworm casts on soil nutrient dynamics and their responses to changing moisture availability in subtropical ecosystems remain poorly understood.This study aimed to examine short-term carbon(C)and nitrogen(N)dynamics and their interactions with wetting-drying cycles in three different structural forms(i.e.,granular,globular,and heap-like)of Amynthas earthworm casts.The rates of C and N mineralization in the earthworm casts were examined under two different wetting-drying cycles(i.e.,2-d and 4-d wetting intervals)using a rainfall simulation experiment.After three simulated rainfall events,subsamples of the earthworm casts were further incubated for 4 d for the determination of CO2 and N2O fluxes.The results of this study indicated that the impacts of wetting-drying cycles on the short-term C and N dynamics were highly variable among the three cast forms,but wetting-drying cycles significantly reduced the cumulative CO2 and N2O fluxes by 62%-83%and 57%-85%,respectively,when compared to the control without being subjected to any rainfall events.The C mineralization rates in different cast forms were affected by the amount of organic substrates and N content in casts,which were associated with the food preference and selection of earthworms.Meanwhile,the cumulative N2O fluxes did not differ among the three cast forms.Repeated wetting and drying of casts not only enhanced aggregate stability by promoting bonds between the cast particles,but also inhibited microbial survival and growth during the prolonged drying period,which together hindered decomposition and denitrification.Our findings demonstrated that the interactions between the structural forms,aggregate dynamics,and C and N cycling in the earthworm casts were highly complex.展开更多
The present study was undertaken to investigate some water quality parameters (pH, BOD, DO and water temperature), anion concentration (PO43- , SO42- and NO3- ) and the availability of some selected microorganisms con...The present study was undertaken to investigate some water quality parameters (pH, BOD, DO and water temperature), anion concentration (PO43- , SO42- and NO3- ) and the availability of some selected microorganisms consisted of total coliform, fecal coliform (Escherichia coli) and Vibrio cholerae in the Dhaleshwari river during the period from April to June 2015. The water samples were collected from three different stations of the river namely Belta (St-1), Kendua (St-2) and Charabari (St-3) under the Porabari union at Tangail Sadar Upazilla. Water temperature varied from 29.5 oC in June to 31.7 oC in May with a highest mean 31.17 ± 0.47 in May. The pH of water was slightly alkaline in nature and ranged between 7.25 in June and 8.45 in April. Mean concentrations of BOD 0.87 ± 0.19, 1.12 ± 0.6 and 0.97 ± 0.67 were recorded in April, May and June respectively. Highest PO42- value 4.4 mg/l was found in May and lowest value of PO42- 1.74 mg/l was found in June. Mean sulfate values at different months of Dhaleshwaririver were 6.61 ± 1.78 mg/l, 7.61 ± 2.16 mg/l and 3.68 ± 0.23 mg/l respectively. Nitrate concentration in water samples varied from 0.51 mg/l in June to 3.66 mg/l in April. Total coliforms bacteria were found high in all water samples and values ranged from 11.05 × 108 - 19 × 1023 cfu/ml. The highest load of total coliforms bacteria was recorded at St-2 in May and the lowest was at St-1 in April. The highest concentration of (Escherichia coli counted in water sample was 6 × 1013 cfu/ml at St-2 during June, while lowest concentration was 5 × 105 cfu/ml at St-1 during May. The highest concentration of Vibrio cholerae was 9.66 × 1014 cfu/ml at St-1 during June, while lowest concentration was 4.2 × 108 cfu/ml at St-3 during April. The high number of total coliform, Escherichia coli and Vibrio cholerae indicated significant level of microbial pollution in Dhaleshwari river. The presence of pathogenic organisms may pose not only health hazards to the users of the river water but also poses risks for the aquatic organisms especially fish of the water bodies. So the occurrence of high bacterial load concluded that the water of Dhaleshwari river is polluted and unhygienic for drinking and even unsuitable for domestic purposes without proper treatment.展开更多
Application of biochar has been highly credited for its potential to sequester carbon and GHG mitigation from tropical agro-ecosystems. However, experiments show inconsistent results depending on soil and biochar type...Application of biochar has been highly credited for its potential to sequester carbon and GHG mitigation from tropical agro-ecosystems. However, experiments show inconsistent results depending on soil and biochar type, cultivation system, climatic condition and the type of evolved GHGs. This study emphasized on the effect of biochar on carbon emission trends from a sequential dry and wet cultivation system of Bangladesh. An incubation study was conducted with two contrasting soils and eight different treatments viz. control, only fertilizer, three different biochars (10 t·ha-1) with and without recommended fertilizer dose. Results revealed the fact that, emission of carbon was substantially higher from Sara soil than Kalma soil. Biochar treatments did not have any easing effect on CO2 emission at field condition;rather, increased in most of the cases. However, emission was significantly (P 2. Biochar application was ineffective to control CH4 and CO release to atmosphere and submergence further intensified their emission significantly. The overall results indicate that applied biochars have negligible effect on carbon emission except for reducing CO2 from submerged soils.展开更多
Surface water, a vital element of ecosystem must be hygienic, but unfortunately the pollution of this water is now an alarming problem. The present work deals with the assessment of physicochemical and bacteriological...Surface water, a vital element of ecosystem must be hygienic, but unfortunately the pollution of this water is now an alarming problem. The present work deals with the assessment of physicochemical and bacteriological profile of several untreated surface water sources to ensure its suitability for using domestic purposes and drinking along with the impact of bacterial contaminated water on public health and antibiotic resistance pattern of these bacteria. The samples were collected from twenty sampling point (13 ponds, 4 lakes, 2 rivers and one canal) of Tangail District from January 2017 to July 2017. To understand the seasonal variation, water samples were measured in two month;February (dry season) and June (wet season). Most of the water sampling points were polluted by dumping of waste, cattle wash and were not suitable for the drinking or other domestic purposes. Obtained results showed that water of the study area is slightly alkaline, no remarkable variation in the temperature of the water in both seasons and DO of all the sampling station were lower than standard limit during February. The mean concentration (M.C.) of total Coliform were 4 × 1022 cfu/100ml and 4.5 × 1018 cfu/100ml at February and June respectively and all the sampling point were contaminated with fecal coliform. Other pathogenic bacteria, E. coli (M.C: 1.1 × 1011 cfu/100ml at February and M.C: 2.2 × 107 cfu/100ml at June), Salmonella spp. (M.C: 1.1 × 105 cfu/100ml at February and M.C: 3.4 × 105 cfu/100ml at June), Shigella spp. (M.C: 8 × 104 cfu/100ml at February and M.C: 3.4 × 107 cfu/100ml at June), Vibrio spp. (M.C: 8.6 × 105 cfu/100ml at February and M.C: 1.1 × 108 cfu/100ml at June) were isolated from several of the investigated water sources. The total counts of these pathogenic bacteria exceeded the acceptable limit during both season and also showed resistance against a broad range of commercially available antibiotics. People who were using these water frequently suffering from various water borne diseases. These untreated water sources pose a major threat to the public health and therefore with need for exigent intervention by government.展开更多
This research examined nitrogen mineralization in the top 10 cm of soils along a vegetation gradient in Hong Kong at sites where fire has been absent for 0, 1, 3, 6 and 17 years (at the time of the study), and the rel...This research examined nitrogen mineralization in the top 10 cm of soils along a vegetation gradient in Hong Kong at sites where fire has been absent for 0, 1, 3, 6 and 17 years (at the time of the study), and the relationships between N mineralization and successional development of vegetation in the absence of fire. The sites including a newly burnt area (S1), short grassland (S2), tall grassland (S3), mixed tall grassland and shrubland (S4), and woodland (S5) were selected,and the in situ core incubation method was used to estimate nitrogen mineralization. Throughout the 60-day incubation in four periods, more nitrogen was mineralized at the S3 and S4 sites, the predominantly grassland sites, which contained the highest levels of soil organic matter (SOM) and total Kjeldahl nitrogen (TKN), than the S1 site, while immobilization occurred at the S2 and S5 sites. Leaching loss decreased with successional development of the vegetation, in the order of S1 ＞ S2 ＞ S3 ＞ S4 ＞ S5. The pattern of nitrogen uptake with ecological succession was less conspicuous, being complicated by the immediate effect of fire and possibly the ability of the woodland species to extract nitrogen from the deeper ground.In the absence of fire for 3 to 6 years, the build-up of SOM and TKN was accompanied by active mineralization, thus paving the way for the invasion of shrub and tree species. A close relationship existed between nitrogen mineralization and ecological succession with this vegetation gradient. Inherent mechanisms to preserve nitrogen in a fire-prone environment including immobilization and uptake and the practical relevance of nitrogen mineralization to reforestation are discussed.展开更多
OBJECTIVE: This article investigates the methods of achieving deep remission of inflammatory bowel disease (IBD). METHODS: Increasing recognition of the concept of quality of care is contributing to the evolution of t...OBJECTIVE: This article investigates the methods of achieving deep remission of inflammatory bowel disease (IBD). METHODS: Increasing recognition of the concept of quality of care is contributing to the evolution of treatment goals in patients with IBD from clinical response and remission (symptom control) toward deep remission. A change in the treatment goal requires a change in the treatment strategy. Optimization of conventional therapy, early treatment, use of the Lemann score, performance of double-balloon endoscopy, treatment using Traditional Chinese Medicine, and good communication between physicians and patients are needed to attain deep remission. RESULTS: The above-mentioned methods can help to achieve deep remission. CONCLUSION: Using the above methods, it will bepossible to improve the prognoses of patients with IBD by minimizing complications and bowel damage and thereby changing the course of the disease.展开更多
The purpose of this study was to offer a general concept and overview of the textile industry’s environmental sustainability assessment.The textile and garment industries cause environmental damage at every stage of ...The purpose of this study was to offer a general concept and overview of the textile industry’s environmental sustainability assessment.The textile and garment industries cause environmental damage at every stage of manufacturing,from the cultivation of raw materials through the disposal of finished goods.Chemical loading,high water consumption,high energy consumption,air pollution,solid waste,and odour creation are all key environmental concerns in the textile industry.To achieve sustainable production,it is necessary to examine the performance of the textile sector while considering the three elements of sustainability.To study and locate recent and related works,five keywords were used:environmental;sustainability;eco-design;manufacturer;supply chain management.All through the life cycle of textile products,the textile sector has a substantial environmental impact.This paper illustrates how the textile industry may use strategic ways to improve ecologically sustainable textile product usage and manufacturing.A discussion is focused on how to be increased sustainability in the textile industry.This paper introduces key principles for ecologically sustainable business practices to consider(e.g.,eco-design,corporate social responsibility,and green supply chain management).It is critical that all stakeholders in the textile industry,including consumers,producers,environmental protection is emphasized in the manufacture and use of textile goods by the distribution chain and customers.展开更多
This study was carried out to determine the concentrations of gaseous air pollutants(CH_(4),PM_(2.5),PM_(10),CO_(2),CO,Cl_(2),NH_(3),SO_(2),NO_(2))and its multifaceted effects on human health in various locations in B...This study was carried out to determine the concentrations of gaseous air pollutants(CH_(4),PM_(2.5),PM_(10),CO_(2),CO,Cl_(2),NH_(3),SO_(2),NO_(2))and its multifaceted effects on human health in various locations in Bangladesh.As Bangladesh is an agricultural country,agricultural biomass burning is a common practice here and this incident typically occurs during the dry season from October to March.Therefore,this study was conducted in seven different areas in dry season where biomass(water hyacinth)was burnt mainly in the river land areas.In this paper,the health impact of biomass burning smoke from agricultural field was examined on the exposed people to the burning pollutants.These pollutants have adverse effects on human health contributing to respiratory problems,cardiovascular diseases,and other health issues.Considering all types of pollutants,excessive amounts of PM_(2.5),PM_(10),CH_(4),and SO_(2) are present in the air.In this study,pollutant concentration methods,spatial distribution methods and exposures assessment methods were used to prepare the project work.From the URB AIR guidebook,the mortality and morbidity were calculated and the results of mortality of excess death high exposure were 68,moderate exposure 32 and average exposure 100.Additionally,Pearson correlation was conducted to find out a relationship among the pollutants including positive correlation between PM_(2.5) and SO_(2)(r=0.777,p<0.05)and PM_(10) and SO_(2)(r=0.725,p<0.05)and negative correlation between SO_(2) and CO(r=-0.868,p<0.05)and PM_(10) and CH_(4)(r=-0.891,p<0.01).Promoting sustainable biomass management,educating communities and providing healthcare facilities with resources and training to recognize and address health issues related to biomass burning exposure may be the best recommendations in the context of reducing pollution level,environmental damage and health risk.展开更多
●High-quality and low-quality root litter had contrasting patterns of mass loss.●Greater litter-derived C was incorporated into soils under high-quality root litter.●Root litter decay rate or litter-derived C were ...●High-quality and low-quality root litter had contrasting patterns of mass loss.●Greater litter-derived C was incorporated into soils under high-quality root litter.●Root litter decay rate or litter-derived C were related to soil microbial diversity.●Root litter quality had little effect on soil physicochemical properties.●High root litter quality was the main driver of enhanced soil C storage efficiency.Decomposing root litter is a major contributor to soil carbon(C)storage in forest soils.During decomposition,the quality of root litter could play a critical role in soil C storage.However,it is unclear whether root litter quality influences soil C storage efficiency.We conducted a two-year greenhouse decomposition experiment using 13C-labeled fine root litter of two tree species to investigate how root litter quality,represented by C to nitrogen(C/N)ratios,regulates decomposition and C storage efficiency in subtropical forest soils in China.‘High-quality’root litter(C/N ratio=26)decayed faster during the first year(0−410 days),whereas‘low-quality’root litter(C/N ratio=46)decomposed faster toward the end of the two-year period(598−767 days).However,over the two years of the study,mass loss from high-quality root litter(29.14±1.42%)was lower than‘low-quality’root litter(33.01±0.54%).Nonetheless,root litter C storage efficiency(i.e.,the ratio of new root litter-derived soil C to total mineralized root litter C)was significantly greater for high-quality root litter,with twice as much litter-derived C stored in soils compared to low-quality root litter at the end of the experiment.Root litter quality likely influenced soil C storage via changes in microbial diversity,as the decomposition of high-quality litter declined with increasing bacterial diversity,whereas the amount of litter-derived soil C from low-quality litter increased with fungal diversity.Our results thus reveal that root litter quality mediates decomposition and C storage in subtropical forest soils in China and future work should consider the links between root litter quality and soil microbial diversity.展开更多
基金supported by the Netherlands Organization for Scientific Research NWO in the form of a VIDI grant(Grant No.VI.Vidi.198.008).
文摘Projections of future urban land change are essential for a range of sustainability assessments,including those related to biodiversity loss,carbon emissions,and agricultural land conversion.However,to what extent and where current projections agree or disagree remains unknown.Here,we systematically compare existing global projections that are consistent with the Shared Socioeconomic Pathways.We find that the total global urban land area is expected to increase by 112%between 2020 and 2100(averaged across all projections),with a coefficient of variation of 0.81.This variation is mostly caused by the selection of the underlying drivers that are included in the different models.Regionally,the highest average growth rates are found in sub-Saharan Africa(+679%to+730%),while this region also has the highest variation across projections(coefficient of variation ranging from 2.02 to 2.18).When ranking scenarios within a study from the highest to the lowest projected increase in urban land,rankings are relatively similar for regions in the Global North,but not for regions in the Global South.The large disagreement across projections can lead to high uncertainties in assessments of future urban land change impacts,which can undermine the effectiveness of long-term planning,policymaking,and resource management decisions.
文摘In Bangladesh,20 gas fields out of 28 produced 709.11 billion cubic feet(Bcf)through 112 wells against a vast amount of demand in the financial year 2021e22.Therefore,more gas fields need to be explored in the most prospective offshore part of Bangladesh.In this study,we have attempted to estimate a prospecting natural gas reserve in the Eastern Fold Belt(Block 18)consisting of Teknaf,Coral Dip,and St Martin Island as well as to develop a production view for the future.Based on the prerequisite research data collected from Petrobangla,Monte Carlo simulations were used to estimate the reserve values as Gas Initially In Place(GIIP)and Recoverable Gas Initially In Place(RGIIP)by Petroleum Engineering(PE)Essential software(version 2017.4).The results show that the estimated GIIP and RGIIP are 6145.88 billion standard cubic feet(Bscf)and 4745.5 Bscf,respectively which are quite close to the previous study.The total estimated proven natural gas of the study is 2064.4 Bcf.
文摘OBJECTIVE: To compare the effects of a Chinese herbal suppository(Jianpi suppository) and Western Medicine(mesalazine) on hemorheology and CD62p in patients with ulcerative colitis(UC).METHODS: In a randomized trial, 120 mild to moderate UC patients were randomly divided into two equal groups. The Jianpi suppository group used Chinese herbal suppository rectally, while the mesalazine group was treated with mesalazine tablets orally. Two 15-day courses of treatment were carried out in both groups. Changes in the hemorheology and CD62p indices in patients were observed.RESULTS: The hemorheology and CD62p indices in the Jianpi suppository group decreased significantly more than those of the mesalazine group.CONCLUSION: Jianpi suppository is effective in improving the hypercoagulability of UC patients, and therefore may be worth using in clinical practice.
基金supported by the National Science Foundation of China (Nos. 41671088 and 41371127)the Program for Innovative Research Team of Fujian Normal University (No. IRTL1205)+2 种基金the Natural Science Foundation of Fujian Province, China (No. 2014J05046)the Study-Abroad Grant Project for Graduates of the School of Geographical Sciences, (No. GY201601)the Graduated Student Science and Technology Innovation Project of the School of Geographical Science,Fujian Normal University (No. GY201601)
文摘Aquaculture ponds are dominant features of the landscape in the coastal zone of China.Generally,aquaculture ponds are drained during the non-culture period in winter.However,the effects of such drainage on the production and flux of greenhouse gases（GHGs）from aquaculture ponds are largely unknown.In the present study,field-based research was performed to compare the GHG fluxes between one drained pond（DP,with a water depth of 0.05 m）and one undrained pond（UDP,with a water depth of 1.16 m）during one winter in the Min River estuary of southeast China.Over the entire study period,the mean CO2flux in the DP was（0.75±0.12）mmol/（m^2·hr）,which was significantly higher than that in the UDP of（-0.49±0.09）mmol/（m^2·hr）（p0.01）.This indicates that drainage drastically transforms aquaculture ponds from a net sink to a net source of CO2in winter.Mean CH4and N2O emissions were significantly higher in the DP compared to those in the UDP（CH4=（0.66±0.31）vs.（0.07±0.06）mmol/（m^2·hr）and N2O=（19.54±2.08）vs.（0.01±0.04）μmol/（m^2·hr））（p〈0.01）,suggesting that drainage would also significantly enhance CH4and N2O emissions.Changes in environmental variables（including sediment temperature,p H,salinity,redox status,and water depth）contributed significantly to the enhanced GHG emissions following pond drainage.Furthermore,analysis of the sustained-flux global warming and cooling potentials indicated that the combined global warming potentials of the GHG fluxes were significantly higher in the DP than in the UDP（p〈0.01）,with values of739.18 and 26.46 mg CO2-eq/（m^2·hr）,respectively.Our findings suggested that drainage of aquaculture ponds can increase the emissions of potent GHGs from the coastal zone of China to the atmosphere during winter,further aggravating the problem of global warming.
基金Project supported by the National Natural Science Foundation of China (Grant No.11071282)the Chinese Program for New Century Excellent Talents in University (Grant No.NCET-08-06867)
文摘Multifractal detrended fluctuation analysis （MF-DFA） is a relatively new method of multifractal analysis. It is extended from detrended fluctuation analysis （DFA）, which was developed for detecting the long-range correlation and the fractal properties in stationary and non-stationary time series. Although MF-DFA has become a widely used method, some relationships among the exponents established in the original paper seem to be incorrect under the general situation. In this paper, we theoretically and experimentally demonstrate the invalidity of the expression r（q） = qh（q） - 1 stipulating the relationship between the multifractal exponent T（q） and the generalized Hurst exponent h（q）. As a replacement, a general relationship is established on the basis of the universal multifractal formalism for the stationary series as .t-（q） = qh（q） - qH - 1, where H is the nonconservation parameter in the universal multifractal formalism. The singular spectra, a and f（a）, are also derived according to this new relationship.
文摘Geodiversity refers to the diversity(or variety, range) of geological(rocks,minerals,fossils),geomorphological (landform) and soil features,and their assemblages,relationships,processes,properties, interpretations and systems.Despite there is a limited area of 1108 km^2,Hong Kong has a remarkably rich geodiversity that includes diversified geology, landforms,and assemblages of associated features and processes.Some geological features can even
基金We thank the Agriculture,Fisheries and Conservation Department of the Hong Kong SAR Government(China)for the permission of field sampling.
文摘Effects of earthworm casts on soil nutrient dynamics and their responses to changing moisture availability in subtropical ecosystems remain poorly understood.This study aimed to examine short-term carbon(C)and nitrogen(N)dynamics and their interactions with wetting-drying cycles in three different structural forms(i.e.,granular,globular,and heap-like)of Amynthas earthworm casts.The rates of C and N mineralization in the earthworm casts were examined under two different wetting-drying cycles(i.e.,2-d and 4-d wetting intervals)using a rainfall simulation experiment.After three simulated rainfall events,subsamples of the earthworm casts were further incubated for 4 d for the determination of CO2 and N2O fluxes.The results of this study indicated that the impacts of wetting-drying cycles on the short-term C and N dynamics were highly variable among the three cast forms,but wetting-drying cycles significantly reduced the cumulative CO2 and N2O fluxes by 62%-83%and 57%-85%,respectively,when compared to the control without being subjected to any rainfall events.The C mineralization rates in different cast forms were affected by the amount of organic substrates and N content in casts,which were associated with the food preference and selection of earthworms.Meanwhile,the cumulative N2O fluxes did not differ among the three cast forms.Repeated wetting and drying of casts not only enhanced aggregate stability by promoting bonds between the cast particles,but also inhibited microbial survival and growth during the prolonged drying period,which together hindered decomposition and denitrification.Our findings demonstrated that the interactions between the structural forms,aggregate dynamics,and C and N cycling in the earthworm casts were highly complex.
文摘The present study was undertaken to investigate some water quality parameters (pH, BOD, DO and water temperature), anion concentration (PO43- , SO42- and NO3- ) and the availability of some selected microorganisms consisted of total coliform, fecal coliform (Escherichia coli) and Vibrio cholerae in the Dhaleshwari river during the period from April to June 2015. The water samples were collected from three different stations of the river namely Belta (St-1), Kendua (St-2) and Charabari (St-3) under the Porabari union at Tangail Sadar Upazilla. Water temperature varied from 29.5 oC in June to 31.7 oC in May with a highest mean 31.17 ± 0.47 in May. The pH of water was slightly alkaline in nature and ranged between 7.25 in June and 8.45 in April. Mean concentrations of BOD 0.87 ± 0.19, 1.12 ± 0.6 and 0.97 ± 0.67 were recorded in April, May and June respectively. Highest PO42- value 4.4 mg/l was found in May and lowest value of PO42- 1.74 mg/l was found in June. Mean sulfate values at different months of Dhaleshwaririver were 6.61 ± 1.78 mg/l, 7.61 ± 2.16 mg/l and 3.68 ± 0.23 mg/l respectively. Nitrate concentration in water samples varied from 0.51 mg/l in June to 3.66 mg/l in April. Total coliforms bacteria were found high in all water samples and values ranged from 11.05 × 108 - 19 × 1023 cfu/ml. The highest load of total coliforms bacteria was recorded at St-2 in May and the lowest was at St-1 in April. The highest concentration of (Escherichia coli counted in water sample was 6 × 1013 cfu/ml at St-2 during June, while lowest concentration was 5 × 105 cfu/ml at St-1 during May. The highest concentration of Vibrio cholerae was 9.66 × 1014 cfu/ml at St-1 during June, while lowest concentration was 4.2 × 108 cfu/ml at St-3 during April. The high number of total coliform, Escherichia coli and Vibrio cholerae indicated significant level of microbial pollution in Dhaleshwari river. The presence of pathogenic organisms may pose not only health hazards to the users of the river water but also poses risks for the aquatic organisms especially fish of the water bodies. So the occurrence of high bacterial load concluded that the water of Dhaleshwari river is polluted and unhygienic for drinking and even unsuitable for domestic purposes without proper treatment.
文摘Application of biochar has been highly credited for its potential to sequester carbon and GHG mitigation from tropical agro-ecosystems. However, experiments show inconsistent results depending on soil and biochar type, cultivation system, climatic condition and the type of evolved GHGs. This study emphasized on the effect of biochar on carbon emission trends from a sequential dry and wet cultivation system of Bangladesh. An incubation study was conducted with two contrasting soils and eight different treatments viz. control, only fertilizer, three different biochars (10 t·ha-1) with and without recommended fertilizer dose. Results revealed the fact that, emission of carbon was substantially higher from Sara soil than Kalma soil. Biochar treatments did not have any easing effect on CO2 emission at field condition;rather, increased in most of the cases. However, emission was significantly (P 2. Biochar application was ineffective to control CH4 and CO release to atmosphere and submergence further intensified their emission significantly. The overall results indicate that applied biochars have negligible effect on carbon emission except for reducing CO2 from submerged soils.
文摘Surface water, a vital element of ecosystem must be hygienic, but unfortunately the pollution of this water is now an alarming problem. The present work deals with the assessment of physicochemical and bacteriological profile of several untreated surface water sources to ensure its suitability for using domestic purposes and drinking along with the impact of bacterial contaminated water on public health and antibiotic resistance pattern of these bacteria. The samples were collected from twenty sampling point (13 ponds, 4 lakes, 2 rivers and one canal) of Tangail District from January 2017 to July 2017. To understand the seasonal variation, water samples were measured in two month;February (dry season) and June (wet season). Most of the water sampling points were polluted by dumping of waste, cattle wash and were not suitable for the drinking or other domestic purposes. Obtained results showed that water of the study area is slightly alkaline, no remarkable variation in the temperature of the water in both seasons and DO of all the sampling station were lower than standard limit during February. The mean concentration (M.C.) of total Coliform were 4 × 1022 cfu/100ml and 4.5 × 1018 cfu/100ml at February and June respectively and all the sampling point were contaminated with fecal coliform. Other pathogenic bacteria, E. coli (M.C: 1.1 × 1011 cfu/100ml at February and M.C: 2.2 × 107 cfu/100ml at June), Salmonella spp. (M.C: 1.1 × 105 cfu/100ml at February and M.C: 3.4 × 105 cfu/100ml at June), Shigella spp. (M.C: 8 × 104 cfu/100ml at February and M.C: 3.4 × 107 cfu/100ml at June), Vibrio spp. (M.C: 8.6 × 105 cfu/100ml at February and M.C: 1.1 × 108 cfu/100ml at June) were isolated from several of the investigated water sources. The total counts of these pathogenic bacteria exceeded the acceptable limit during both season and also showed resistance against a broad range of commercially available antibiotics. People who were using these water frequently suffering from various water borne diseases. These untreated water sources pose a major threat to the public health and therefore with need for exigent intervention by government.
基金Project supported by the Commonwealth Fellowship Scheme and the United College Endowment Fund of the Chinese University of Hong Kong
文摘This research examined nitrogen mineralization in the top 10 cm of soils along a vegetation gradient in Hong Kong at sites where fire has been absent for 0, 1, 3, 6 and 17 years (at the time of the study), and the relationships between N mineralization and successional development of vegetation in the absence of fire. The sites including a newly burnt area (S1), short grassland (S2), tall grassland (S3), mixed tall grassland and shrubland (S4), and woodland (S5) were selected,and the in situ core incubation method was used to estimate nitrogen mineralization. Throughout the 60-day incubation in four periods, more nitrogen was mineralized at the S3 and S4 sites, the predominantly grassland sites, which contained the highest levels of soil organic matter (SOM) and total Kjeldahl nitrogen (TKN), than the S1 site, while immobilization occurred at the S2 and S5 sites. Leaching loss decreased with successional development of the vegetation, in the order of S1 ＞ S2 ＞ S3 ＞ S4 ＞ S5. The pattern of nitrogen uptake with ecological succession was less conspicuous, being complicated by the immediate effect of fire and possibly the ability of the woodland species to extract nitrogen from the deeper ground.In the absence of fire for 3 to 6 years, the build-up of SOM and TKN was accompanied by active mineralization, thus paving the way for the invasion of shrub and tree species. A close relationship existed between nitrogen mineralization and ecological succession with this vegetation gradient. Inherent mechanisms to preserve nitrogen in a fire-prone environment including immobilization and uptake and the practical relevance of nitrogen mineralization to reforestation are discussed.
文摘OBJECTIVE: This article investigates the methods of achieving deep remission of inflammatory bowel disease (IBD). METHODS: Increasing recognition of the concept of quality of care is contributing to the evolution of treatment goals in patients with IBD from clinical response and remission (symptom control) toward deep remission. A change in the treatment goal requires a change in the treatment strategy. Optimization of conventional therapy, early treatment, use of the Lemann score, performance of double-balloon endoscopy, treatment using Traditional Chinese Medicine, and good communication between physicians and patients are needed to attain deep remission. RESULTS: The above-mentioned methods can help to achieve deep remission. CONCLUSION: Using the above methods, it will bepossible to improve the prognoses of patients with IBD by minimizing complications and bowel damage and thereby changing the course of the disease.
文摘The purpose of this study was to offer a general concept and overview of the textile industry’s environmental sustainability assessment.The textile and garment industries cause environmental damage at every stage of manufacturing,from the cultivation of raw materials through the disposal of finished goods.Chemical loading,high water consumption,high energy consumption,air pollution,solid waste,and odour creation are all key environmental concerns in the textile industry.To achieve sustainable production,it is necessary to examine the performance of the textile sector while considering the three elements of sustainability.To study and locate recent and related works,five keywords were used:environmental;sustainability;eco-design;manufacturer;supply chain management.All through the life cycle of textile products,the textile sector has a substantial environmental impact.This paper illustrates how the textile industry may use strategic ways to improve ecologically sustainable textile product usage and manufacturing.A discussion is focused on how to be increased sustainability in the textile industry.This paper introduces key principles for ecologically sustainable business practices to consider(e.g.,eco-design,corporate social responsibility,and green supply chain management).It is critical that all stakeholders in the textile industry,including consumers,producers,environmental protection is emphasized in the manufacture and use of textile goods by the distribution chain and customers.
文摘This study was carried out to determine the concentrations of gaseous air pollutants(CH_(4),PM_(2.5),PM_(10),CO_(2),CO,Cl_(2),NH_(3),SO_(2),NO_(2))and its multifaceted effects on human health in various locations in Bangladesh.As Bangladesh is an agricultural country,agricultural biomass burning is a common practice here and this incident typically occurs during the dry season from October to March.Therefore,this study was conducted in seven different areas in dry season where biomass(water hyacinth)was burnt mainly in the river land areas.In this paper,the health impact of biomass burning smoke from agricultural field was examined on the exposed people to the burning pollutants.These pollutants have adverse effects on human health contributing to respiratory problems,cardiovascular diseases,and other health issues.Considering all types of pollutants,excessive amounts of PM_(2.5),PM_(10),CH_(4),and SO_(2) are present in the air.In this study,pollutant concentration methods,spatial distribution methods and exposures assessment methods were used to prepare the project work.From the URB AIR guidebook,the mortality and morbidity were calculated and the results of mortality of excess death high exposure were 68,moderate exposure 32 and average exposure 100.Additionally,Pearson correlation was conducted to find out a relationship among the pollutants including positive correlation between PM_(2.5) and SO_(2)(r=0.777,p<0.05)and PM_(10) and SO_(2)(r=0.725,p<0.05)and negative correlation between SO_(2) and CO(r=-0.868,p<0.05)and PM_(10) and CH_(4)(r=-0.891,p<0.01).Promoting sustainable biomass management,educating communities and providing healthcare facilities with resources and training to recognize and address health issues related to biomass burning exposure may be the best recommendations in the context of reducing pollution level,environmental damage and health risk.
基金supported by the National Natural Science Foundation of China(Grant No.31901135)the Guangdong Natural Science Foundation(Grant No.2020A1515011257)+1 种基金the Research Grants Council of the Hong Kong Special Administrative Region,China(Grant Nos.CUHK14302014,CUHK14305515 and CUHK14122521)the Chinese University of Hong Kong(Grant No.4052228).
文摘●High-quality and low-quality root litter had contrasting patterns of mass loss.●Greater litter-derived C was incorporated into soils under high-quality root litter.●Root litter decay rate or litter-derived C were related to soil microbial diversity.●Root litter quality had little effect on soil physicochemical properties.●High root litter quality was the main driver of enhanced soil C storage efficiency.Decomposing root litter is a major contributor to soil carbon(C)storage in forest soils.During decomposition,the quality of root litter could play a critical role in soil C storage.However,it is unclear whether root litter quality influences soil C storage efficiency.We conducted a two-year greenhouse decomposition experiment using 13C-labeled fine root litter of two tree species to investigate how root litter quality,represented by C to nitrogen(C/N)ratios,regulates decomposition and C storage efficiency in subtropical forest soils in China.‘High-quality’root litter(C/N ratio=26)decayed faster during the first year(0−410 days),whereas‘low-quality’root litter(C/N ratio=46)decomposed faster toward the end of the two-year period(598−767 days).However,over the two years of the study,mass loss from high-quality root litter(29.14±1.42%)was lower than‘low-quality’root litter(33.01±0.54%).Nonetheless,root litter C storage efficiency(i.e.,the ratio of new root litter-derived soil C to total mineralized root litter C)was significantly greater for high-quality root litter,with twice as much litter-derived C stored in soils compared to low-quality root litter at the end of the experiment.Root litter quality likely influenced soil C storage via changes in microbial diversity,as the decomposition of high-quality litter declined with increasing bacterial diversity,whereas the amount of litter-derived soil C from low-quality litter increased with fungal diversity.Our results thus reveal that root litter quality mediates decomposition and C storage in subtropical forest soils in China and future work should consider the links between root litter quality and soil microbial diversity.
