Impacts of tourism development on the physical environment of Mussoorie,a hill station in the lower Himalayan range of India

Tourism in mountainous regions is a significant source of revenue generation. However, it has also been associated with many adverse environmental consequences. This study aims at assessing the negative impacts of the incessant upsurge in tourism development on the physical environment of Mussoorie, a well-known mountain tourist destination in India. The impact indicators for the region were identified and assessed by qualitative and quantitative analysis of field observations. The observations indicated the aggravation of traffic congestion, atmospheric pollution, undisposed solid waste, water scarcity and infrastructure unavailability as the prevalent issues, especially during the peak tourist months. The extent of the consequential damage to the environment was evaluated by conducting an assessment of tourism-induced human disturbance on the natural landscape of the town. Slope, slope aspect, vegetation cover, road network and drainage network were incorporated as thedetermining landscape attributes to prepare thematic maps of landscape quality(perceivable intrinsic properties) and landscape fragility(vulnerability to anthropogenic disturbances) using GIS technique. An absorption capacity map was finally prepared to characterize the study area into regions of different conservation needs. The results identified the need for planning appropriate preservation strategies for different tourist places in the town. The study can be used by the policy makers for implementing the regulatory measures against potential disturbances due to mass-tourism.

Carbon emission scenarios of China's power sector:Impact of controlling measures and carbon pricing mechanism

The study constructs a low-carbon path analysis model of China's power sector based on TIMES model and presents a comparative analysis of carbon emissions under Reference,Low-Carbon and Enhanced Low-Carbon scenarios,and the main difference of the three scenarios is manifested by policy selection and policy strength.The conclusions are drawn as follows:(1)The peak of carbon emission in China's power sector will range from 4.0 GtCO2 to 4.8 GtCO2,which implies an increment of 0.5e1.3 billion or 14%e35%from the 2015 levels.(2)Introducing carbon price is an effective way to inhibit coal power and promote non-fossil fuels and Carbon Capture,Utilization and Storage applications(CCUS).The carbon emission reduction effects will gradually increase with carbon price.When the carbon price attains to CN￥150 t
1CO2,the CO2 emission can decrease by 36%than that without carbon price.(3)CCUS is one of important contributing factor to reduce CO2 emission in power sector.Generally speaking,the development of non-fossil fuels and energy efficiency improvement are two main drivers for carbon mitigation,but once the carbon price reaches up to CN￥106 t
1CO2,the CCUS will be required to equip with thermal power units and its contribution on carbon emission reduction will remarkably increase.When carbon price increases to CN￥150 t
1CO2 in 2050,the application of CCUS will account for 44%of total emission reduction.(4)In the scenario with carbon price of CN￥150 t
1CO2,power sector would be decarbonized significantly,and the CO2 intensity will be 0.22 kgCO2(kW h)
1,but power sector is far from the goal that achieving net zero emission.In order to realize the long-term low greenhouse gas emission development goal that proposed by the Paris Agreement,more efforts are needed to be put to further reduce the carbon emission reduction of power sector.Based on the above scenario analysis,the study proposes four recommendations on the low-carbon development of China's power sector:(1)improve the energy efficiency proactively and optimize the energy structure of power sector gradually;(2)promote the low-carbon transition of power sector by using market-based mechanism like carbon emission trading scheme to internalize the external cost of carbon emission;(3)give more emphasis on and support to the CCUS application in power sector.

Long-term costs and benefits analysis of China’s low-carbon policies

China’s long-term,low-emission development goals will hinge on effective low-carbon policies.Therefore,it is valuable to evaluate the costs and benefits of low-carbon policy packages to ensure that low-carbon development concepts and strategies can be well integrated into the policy making process.This work uses the Low-carbon Policy Assessment(LPA)model to assess long-term costs and benefits of climate and energy policies in China under the reference(RS)scenario and the low-carbon(LC)scenario,which includes 25 additional climate and energy policies.In the LC scenario,both energy-related CO2 emissions and total greenhouse gas(GHG)emissions peak around 2030,achieving China’s Nationally Determined Contribution(NDC)target.Of the policies included in the LC scenario,the five with the highest GHG mitigation potential beyond China’s existing policies are:fluorinated gas(F-gas)substitution,a renewable portfolio standard,carbon pricing,carbon capture utilization and storage(CCUS),and a fuel economy standard for heavy duty vehicles(HDVs).In addition to reducing GHG emissions,these policies decrease particulate emissions and associated premature deaths,which would otherwise reduce China’s GDP by nearly 1.5%in 2050.Together,these policies have the potential to promote significant low-carbon prosperity in China.

BiOCl-Bi12O17Cl2 nanocomposite with high visible-light photocatalytic activity prepared by an ultrasonic hydrothermal method for removing dye and pharmaceutical

A BiOCl-Bi12O17Cl2 nanocomposite with a high visible-light response and a low photoinduced electron-hole pair recombination rate was successfully synthesized using an ultrasonic-hydrothermal method.The texture,structure,optical,and photocatalytic properties of the composite were characterized.The results showed that the composite had a sheet flower-like structure with a large specific surface area.Ultraviolet-visible diffuse reflection spectra and photoluminescence spectra showed that the composite had an excellent visible-light response and a low recombination rate of photoinduced electron hole pairs.The photocatalytic property of the composite was evaluated by the removal efficiency of rhodamine B and ciprofloxacin under visible-light illumination.The composite’s reaction rate constant of removing rhodamine B(/ciprofloxacin)was approximately 8.14(/4.94),42.63(/11.91)and 64.66(/36.07)times that of Bi12O17Cl2,P25,and BiOCl,respectively.Furthermore,the composite showed a wide applicable pH range and excellent reusability.Mechanism analysis showed that photogenerated holes played a dominant role and·O2–also contributed to photocatalytic degradation.In summary,this study presents a high-efficiency photocatalyst for wastewater treatment.

China's long-term low carbon transition pathway under the urbanization process

This study develops a comprehensive analysis framework and socio-economic energy system model that interlinks demographic change and energy system in order to analyze the urbanization process and its relation with China's long-term CO2 emissions trend as China'economy enters the“new normal”stage.The results show that,around 300 million people are expected to migrate from rural areas to urban areas by 2050 following a trend,in which people are moving gradually from small and medium city groups to large and super city groups.The migration trend together with the improvement in living standard will promote China's infrastructure construction,industry production,and energy service demand growth.Under the Business as Usual(BAU)scenario,total primary energy consumption in China will reach 8.4 Gtce by 2050,energyrelated CO2 emissions will increase to 17.6 Gt,which is 83%higher than the 2013 level.While in the Low Carbon Transition(LCT)scenario with technology innovation,the total primary energy demand for China in 2050 could be controlled at^6 Gtce;CO2 emissions would peak during 2020—2025,and be reduced by 78%by 2050 compared to the BAU scenario.In the transition process,non-fossil fuel power generation and energy efficiency technologies have the largest mitigation potentials.Industry and power sectors would peak first before 2020,followed by the building and transport sectors which are projected to peak around 2030.The total additional capital investment required for LCT would account for 1.5%of GDP.Therefore,it is technologically and economically feasible for China to implement new urbanization strategy.

Pathway and policy analysis to China's deep decarbonization

The Paris Agreement marks the beginning of a new era in the global response to climate change, which further clarifies the long-term goal and underlines the urgency addressing climate change. For China,promoting the decoupling between economic growth and carbon emissions as soon as possible is not only the core task of achieving the medium-and long-term goals and strategies to address climate change, but also the inevitable requirement for ensuring the sustainable development of economy and society. Based on the analysis of the historical trends of the economy and social development, as well as society, energy consumption, and key end-use sectors in China, this paper studies the deep carbon emission reduction potential of carbon emission of in energy, industry, building, and transportation and other sectors with "bottom-up" modeling analysis and proposes a medium-and long-term deep decarbonization pathway based on key technologies' mitigation potentials for China. It is found that under deep decarbonization pathway, China will successfully realize the goals set in China's Intended Nationally Determined Contributions of achieving carbon emissions peak around 2030 and lowering carbon dioxide emissions per unit of gross domestic product(GDP) by 60-65% from the 2005 level.From 2030 onward, the development of nonfossil energy will further accelerates, and the share of nonfossil energies in primary energy will amounts to about 44% by 2050. Combined with the acceleration of low-carbon transformation in end-use sectors including industry, building, and transportation, the carbon dioxide emissions in 2050 will fall to the level before 2005, and the carbon dioxide emissions per unit of GDP will decreases by more than 90% from the 2005 level. To ensure the realization of the deep decarbonization pathway, this paper puts forward policy recommendations from four perspectives, including intensifying the total carbon dioxide emissions cap and strengthening the related institutional systems and regulations, improving the incentive policies for industrial lowcarbon development, enhancing the role of the market mechanism, and advocating low-carbon life and consumption patterns.

Green manufacturing for achieving carbon neutrality goal requires innovative technologies:A bibliometric analysis from 1991 to 2022

Recent years have seen a significant increase in interest in green manufacturing as a key driver of global carbon-neutral efforts and sustainable development.To find the research hotspots of green manufacturing and reveal future research trends,this study reviewed and analyzed research articles from the Web of Science database on green manufacturing from1991 to 2022 using a bibliometric method.The findings indicate a significant rise in the number of articles related to green manufacturing since the 2010s.Moreover,there has been an increase in the involvement of scholars from developing countries such as China and India in this field.Based on the literature review and bibliometric cluster analysis on green manufacturing,we believed that future research may continue following the lines of intelligent technology integration,adoption of frontier engineering techniques,and industry development in line with carbon reduction targets.A framework for future green manufacturing development is proposed,with a focus on Chinese policies.The framework could provide policy implications for developing countries looking to pursue opportunities for development in green manufacturing.

Cesium removal from radioactive wastewater by adsorption and membrane technology

Radiocesium is frequently present in radioactive wastewater,while its removal is still a challenge due to its small hydrated radius,high diffusion coefficient,and similar chemical behavior to other alkali metal elements with high background concentrations.This review summarized and analyzed the recent advances in the removal of Cs+from aqueous solutions,with a particular focus on adsorption and membrane separation methods.Various inorganic,organic,and biological adsorbents have undergone assessments to determine their efficacy in the removal of cesium ions.Additionally,membrane-based separation techniques,including reverse osmosis,forward osmosis,and membrane distillation,have also shown promise in effectively separating cesium ions from radioactive wastewater.Additionally,this review summarized the main approaches,including Kurion/SARRY system+desalination system and advanced liquid processing system,implemented after the Fukushima Daiichi nuclear power plant accident in Japan to remove radionuclides from contaminated water.Adsorption technology and membrane separation technology play a vital role in treatment of contaminated water.

Preparation and application of a new catalyst to produce bio-oil from microalgae liquefaction

In this study,hydrothermal catalytic liquefaction method was adopted to produce bio-oil from microalgae.The influence of supported Ni-Catalysts doped neodymium(Nd)on the bio-oil yield from microalgae liquefaction was investigated,aiming to find the optimal preparation procedure of bio-oil.It proved that under the condition of a temperature of 270℃and a reaction period of 30 min,the bio-oil yield of hydrothermal catalytic liquefaction of spirulina powder could reach 55.1%by means of the catalyst prepared with 1 mol/L neodymium nitrate as the dipping solution after a calcination for 4 h at 800℃.In addition,the characterization on catalyst was discussed in this research.

Effect of the ultraviolet/chlorine process on microbial community structure,typical pathogens,and antibiotic resistance genes in reclaimed water

Urban wastewater contains a wide range of pathogens and antibiotic resistance genes(ARGs),which are a serious concern if reusing treated wastewater.However,few studies have explored the microbial communities in reclaimed water using ultraviolet(UV)/chlorine treatment and assessed the changes of the resistome.This study investigated the occurrence of typical pathogens,ARGs,and bacterial communities in UV/chlorine-treated reclaimed water samples.The numbers of culturable and viable but non-culturable pathogens were effectively reduced to 0 CFU/mL within 1–10 and 10–30 min after UV/chlorine treatment,respectively.Meanwhile,the physicochemical indices of water quality were not affected.UV/chlorine treatment could significantly change the bacterial community structure of reclaimed water,showing a decrease in bacterial abundance and diversity.Chlorine-resistant Acinetobacter and Mycobacterium were the dominant bacterial genera(>50%)after UV/chlorine treatment.Moreover,the number of ARGs and mobile genetic elements(MGEs)decreased with an increase in UV/chlorine exposure.However,eight ARGs and three MGEs were consistently detected in more than three seasons,making these major concerns because of their potential role in the persistence and dissemination of antibiotic resistance.Overall,the results of this study suggest that UV/chlorine treatment can potentially improve the microbiological safety of reclaimed water.And more attention should be paid to the pathogens that are both chlorine-resistant and carry MGEs because of their potential for resistance transmission.

Fabrication of Bi-Bi3O4Cl plasmon photocatalysts for removal of aqueous emerging contaminants under visible light

Photocatalytic oxidation of emerging contaminants(ECs) in water has recently gained extensive attentions. In this study, bismuth oxychloride-based plasmon photocatalysts(BiBiOCl) exhibiting high performance were successfully developed by reducing Bion the surface of BiOCl. Consequently, the photocatalysts were used to remove ECs from water.The effects of developmental process and Bi metal plasmon resonance on the photoelectric performances of Bi-BiOCl were investigated through a series of characterizations. The UV-vis diffuse reflection and photoluminescence spectra revealed that the light absorption range of the photocatalyst gradually increased and the electron recombination rate gradually decreased with the introduction of Bi metals. The optimal removal rates of ciprofloxacin and tetrabromobisphenol A by Bi-BiOCl were 93.8% and 96.4%;the respective reaction rate constants were 5.48 and 4.93 times higher than that of BiOCl. The mechanism study indicated that main reactants in the photocatalytic system were ·O-2radicals and photogenerated holes, and the existence of oxygen vacancies and Bi metals promoted electron transfer in photocatalyst. In conclusion, this research produces a novel, green, highly efficient, and stable visible light photocatalyst for the removal of ECs from water.

Revealing the changes of bacterial community from water source to consumers tap:A full-scale investigation in eastern city of China

This study profiled the bacterial community variations of water from four water treatment systems,including coagulation,sedimentation,sand filtration,ozonation-biological activated carbon filtration(O3-BAC),disinfection,and the tap water after the distribution process in eastern China.The results showed that different water treatment processes affected the bacterial community structure in different ways.The traditional treatment processes,including coagulation,sedimentation and sand filtration,reduced the total bacterial count,while they had little effect on the bacterial community structure in the treated water(before disinfection).Compared to the traditional treatment process,O3-BAC reduced the relative abundance of Sphingomonas in the finished water.In addition,ozonation may play a role in reducing the relative abundance of Mycobacterium.NaClO and ClO2 had different effects on the bacterial community in the finished water.The relative abundance of some bacteria(e.g.Flavobacterium,Phreatobacter and Porphyrobacter)increased in the finished water after ClO2 disinfection.The relative abundance of Mycobacterium and Legionella,which have been widely reported as waterborne opportunistic pathogens,increased after NaClO disinfection.In addition,some microorganisms proliferated and grew in the distribution system,which could lead to turbidity increases in the tap water.Compared to those in the finished water,the relative abundance of Sphingomonas,Hyphomicrobium,Phreatobacter,Rheinheimera,Pseudomonas and Acinetobacter increased in the tap water disinfected with NaClO,while the relative abundance of Mycobacterium increased in the tap water disinfected with ClO2.Overall,this study provided the detailed variation in the bacterial community in the drinking water system.

Rapid flood inundation mapping by differencing water indices from pre-and post-flood Landsat images

Following flooding disasters,satellite images provide valuable information required for generating flood inundation maps.Multispectral or optical imagery can be used for generating flood maps when the inundated areas are not covered by clouds.We propose a rapid mapping method for identifying inundated areas based on the increase in the water index value between the pre-and post-flood satellite images.Values of the Normalized Difference Water Index(NDWI)and Modified NDWI(MNDWI)will be higher in the post-flood image for flooded areas compared to the pre-flood image.Based on a threshold value,pixels corresponding to the flooded areas can be separated from non-flooded areas.Inundation maps derived from differencing MNDWI values accurately captured the flooded areas.However the output image will be influenced by the choice of the pre-flood image,hence analysts have to avoid selecting pre-flood images acquired in drought or earlier flood years.Also the inundation maps generated using this method have to be overlaid on the post-flood satellite image in order to orient personnel to landscape features.Advantages of the proposed technique are that flood impacted areas can be identified rapidly,and that the pre-existing water bodies can be excluded from the inundation maps.Using pairs of other satellite data,several maps can be generated within a single flood which would enable emergency response agencies to focus on newly flooded areas.

Heritage tourism evolution in Guangfu Ancient City,Hebei Province,China:an analysis with the improved creative destruction model

Ancient cities and towns are popular tourism destinations worldwide.In this paper,Guangfu Ancient City in Yongnian County,Hebei Province,China,is taken as the case study and the modifed creative destruction model is applied as the analytical framework to evaluate the multiactor dynamics of heritage tourism development.A mixed method approach is adopted,including a local resident survey,in-depth interviews with staf of the Guangfu Ancient City tourism site and government ofcials responsible for the heritage conservation and tourism development of the site,and a review of online tourist reviews,relevant government documents and reports.Based on the modifed creative destruction model,local residents’attitudes towards tourism development,changes in tourist numbers,the level of business and government investments,and the motivations of diferent stakeholders in tourism development are assessed by synthesising on-site research,historical data and other materials.Then,the tourism development stages for Guangfu Ancient City are identifed as the precommodifcation stage before 2006,the early commodifcation stage from 2006 to 2011 and the advanced commodifcation stage from 2012 to 2017.The fndings indicate that with rapid increases in investments from both corporate and government sources and in the number of tourists,the attitude of local residents towards tourism development remained positive.The results show that instead of entering the initial destruction stage,Guangfu Ancient City is in the transition stage from advanced commodifcation to creative enhancement given the government’s dominant role in tourism development,the heritage conservation motives of tourism entrepreneurs,the benefts to residents from tourism development ensured by government policies,and the shift in tourist type to postmodern tourists with double demands.The applicability of the modifed creative destruction model is further discussed,and policy and management recommendations are generated to support the sustainable development of Guangfu Ancient City after the COVID-19 pandemic.