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Engineering 2024年第4期35卷 214-225页

作者： Yang Xiao Bo Zhou Siyuan Tan Lei Li Tahir Muhammad Buchun Si Changjian Ma Sunny C.Jiang Yunkai Li College of Water resources and Civil Engineering China Agricultural UniversityBeijing 100083China Engineering Research Center for agricultural Water-Saving and Water resources(Ministry of Education of the People’s Republic of China) China Agricultural UniversityBeijing 100083China School of Environment and Civil Engineering Dongguan University of TechnologyDongguan 523808China State Key Laboratory of Nutrient Use and management Institute of Agricultural Resources and EnvironmentShandong Academy of Agricultural SciencesJinan 250100China Department of Civil and Environmental Engineering University of California-IrvineIrvineCA 92617USA

The increasing demand for wastewater treatment has become a notable trend for addressing global water ***,fouling is a significant challenge for wastewater distribution engineering *** study provides an approach using nanobubbles(NBs)to control *** antifouling capacities of three types of NBs,six oxygen concentrations,and two application procedures(prevention and removal)are *** results show that NBs effectively mitigate composite fouling—including biofouling,inorganic scaling,and particulate fouling—in comparison with the non-NBs *** specifically,hydroxyl radicals generated by the self-collapse of NBs oxidize organics and kill microorganisms in *** negatively charged surfaces of the NBs transform the crystalline form of CaCO_(3)from calcite to looser aragonite,which reduces the likelihood of ion ***,the NBs gas-liquid interfaces act as gas"bridges"between colloidal particles,enhancing the removal of particles from ***,although the NBs inhibit the growth of fouling,they do not significantly remove the already adhered fouling in non-NBs treated *** study anticipates that the application of NBs will address the significant fouling issue for various wastewater distribution engineering systems in order to meet the global challenge of sustainable water supplies.

关键词： Biofouling Scaling Colloidal fouling Wastewater Antifouling mechanism

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Hydrodynamic Assessment of A New Nature-Based Armour Unit on Rubble Mound Breakwater for Coastal Protection

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China Ocean Engineering 2024年第3期38卷 439-452页

作者： Ehsan SAFA Alireza MOJTAHEDI Abdolmajid MOHAMMADIAN Mohamad Ali Lotfollahi YAGHIN Department of Water resources Engineering Faculty of Civil EngineeringUniversity of TabrizTabriz ***Iran faculty of Civil Engineering University of OttawaOttawa K1H 8M5Canada

This research proposes a novel nature-based design of a new concrete armour unit for the cover layer of a rubblemoundbreakwater. Armour units are versatile with respect to shape, orientation, surface condition details, and ***, a detailed analysis is required to investigate the exact state of their hydraulic interactions and structuralresponses. In this regard, the performance results of several traditional armour units, including the Antifer cube,Tetrapod, X-block and natural stone, are considered for the first step of this study. Then, the related observed resultsare compared with those obtained for a newly designed (artificial coral) armour unit. The research methodology utilizesthe common wave flume test procedure. Furthermore, several verified numerical models in OpenFOAM code areused to gain the extra required data. The proposed armour is configured to provide an effective shore protection as anenvironmental-friendly coastal structure. Thus it is designed with a main trunk including deep grooves to imitate thetypical geometry of a coral type configuration, so as to attain desirable performance. The observed results and ananalytic hierarchy process (AHP) concept are used to compare the hydraulic performance of the studied traditionaland newly proposed (artificial coral) armour units. The results indicate that the artificial coral armour unit demonstratesacceptable performance. The widely used traditional armour units might be replaced by newer designs for betterwave energy dissipation, and more importantly, for fewer adverse effects on the marine environment.

关键词： rubble mound breakwater hydraulic interaction armour unit analytic hierarchy process numerical model

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Community perspectives on the effectiveness of watershed management institutions in the Himalayas

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Journal of Mountain Science 2024年第4期21卷 1119-1139页

作者： Nisha SILWAL Nabin DHUNGANA Rajan SUBEDI Suraj UPADHAYA Chun-Hung LEE natural resources Conservation Nepal(NRCN) ChitwanP.O.Box 44200Nepal Department of natural resources and Environmental Studies College of Environmental StudiesNational Dong Hwa UniversityHualien 97401Chinese Taipei Institute of Forestry Tribhuvan UniversityPokharaP.O.Box 43Nepal School of Agriculture and natural resources Kentucky State UniversityFrankfortKY 40601USA Himalayan Conservation and Research Institute DolpaP.O.Box 21400Nepal

The sustainability of environmental management initiatives,such as watershed management programs,relies on the presence of effective institutions at the watershed ***,there needs to be more empirical evidence from evaluating the effectiveness of watershed-level ***,this study presents a pioneering effort to evaluate the effectiveness of Nepal’s first watershed conservation committee at the watershed scale,focusing on the case of the Khageri Khola watershed in Central *** study involved conducting a household survey,key informant interviews,focus group discussions,and field observations to collect and analyze the *** analysis,index value calculation,and chi-square statistics were then employed to summarize the results regarding local respondents’perceptions of twelve institutional characteristics,their rationalities,and their association with socio-demographic *** results reveal that the watershed conservation committee was perceived as performing well in managing the ***,good interaction,appropriate scale,technical,environmental,social,organizational,and government rationality were perceived as highly effective,with an average index value of less than *** contrast,clarity of objectives and economic rationality showed moderate effectiveness,with an average index value ranging from 0.36 to ***,the results suggested that adaptiveness,compliance capacity,and financial rationality merit increased attention,intending to improve their ***,the results showed the association of socio-demographics with respondents’perceptions of various indicators of institutional characteristics and their ***,the study provides valuable insights for policymakers,researchers,and development practitioners charged with designing sustainable and effective programs and *** enhance the effectiveness and sustainability of watershed management programs,we recommen

关键词： Watershed Watershed institutions Indicators Institutional characteristics Rationalities Nepal.

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Modeling the effect of stand and site characteristics on the probability of mistletoe infestation in Scots pine stands using remote sensing data

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Forest Ecosystems 2024年第3期11卷 296-306页

作者： Luiza Tymińska-Czabańska Piotr Janiec Pawel Hawrylo Jacek Slopek Anna Zielonka Pawel Netzel Daniel Janczyk Jaroslaw Socha Department of Forest resources management Faculty of ForestryUniversity of Agriculture in KrakowAl.29 Listopada 46Krakow31-425Poland Forest management and Geodesy Bureau Ul.Lesnikow 2105-090Sekocin StaryPoland Department of Geoinformatics and Cartography Institute of Geography and Regional DevelopmentFaculty of Earth Sciences and Environmental ManagementUniversity of WroclawPl.Uniwersytecki 1WroclawPoland Institute of Geography and Spatial management Faculty of Geography&GeologyJagiellonian University in KrakowUl.Gronostajowa 730-387Poland Torun Regional Directorate of State Forests Ul.Adama Mickiewicza 987-100TorunPoland

Over the past decade,the presence of mistletoe(Viscum album ***)in Scots pine stands has increased in many European *** the factors that influence the occurrence of mistletoe in stands is key to making appropriate forest management decisions to limit damage and prevent the spread of mistletoe in the ***,the main objective of this study was to determine the probability of mistletoe occurrence in Scots pine stands in relation to stand-related endogenous factors such as age,top height,and stand density,as well as topographic and edaphic *** used unmanned aerial vehicle(UAV)imagery from 2,247 stands to detect mistletoe in Scots pine stands,while majority stand and site characteristics were calculated from airborne laser scanning(ALS)*** on stand age and site type from the State Forest database were also *** found that mistletoe infestation in Scots pine stands is influenced by stand and site *** documented that the densest,tallest,and oldest stands were more susceptible to mistletoe *** type and specific microsite conditions associated with topography were also important factors driving mistletoe *** addition,climatic water balance was a significant factor in increasing the probability of mistletoe occurrence,which is important in the context of predicted temperature increases associated with climate *** results are important for better understanding patterns of mistletoe infestation and ecosystem functioning under climate *** an era of climate change and technological development,the use of remote sensing methods to determine the risk of mistletoe infestation can be a very useful tool for managing forest ecosystems to maintain forest sustainability and prevent forest disturbance.

关键词： Generalized additive models Tree infestation Mistletoe occurrence ALS UAV Scots pine

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Spatial-temporal shifting patterns and in situ conservation of spotted seal(Phoca largha)populations in the Yellow Sea ecoregion

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Integrative Zoology 2024年第2期19卷 307-318页

作者： Hongfei ZHUANG Fei SHAO Chao ZHANG Wancai XIA Shouqiang WANG Fangyuan QU Zongling WANG Zhichuang LU Linlin ZHAO Zhaohui ZHANG First Institute of Oceanography Ministry of Natural ResourcesQingdaoChina Department of natural resources of Shandong Province Shandong Forestry Protection and Development Service CenterJinanChina National Park(Protected Areas)Development Center National Forestry and Grassland AdministrationBeijingChina College of Life Science China West Normal UniversityNanchongChina Liaoning Ocean and Fisheries Science Research Institute DalianChina

Understanding the habitat shifting pattern is a prerequisite for implementing in situ conservation of migratory *** seals(Phoca largha)inhabiting the Yellow Sea ecoregion(YSE)comprise a small population with independent genes and represent a charismatic flagship species in this ***,this population has declined by 80%since the 1940s,and increased support from the countries around the YSE is urgently needed to address the potential local extinction risk.A time-series niche model and life-history weighted systematic conservation planning were designed on the basis of a satellite beacon tracking survey(2010–2020)of the YSE *** results showed clustering and spreading shifting patterns during the breeding and migratory seasons,*** closed-loop migration route formed in the YSE indicated that this population might be geographically isolated from populations in other breeding areas around the *** conservation priority area(CPA),with an area of 19632 km^(2)(3.58%of the total YSE area),was the most effective response to the potential in situ ***,nearly 80%of the CPA was exposed outside the existing marine protected areas(MPAs).Future establishment of MPAs in China should strategically consider the conservation gap identified herein,and it is recommended for Korea’s closed fishing season to be spatially set in the western Korean Peninsula from May to *** study also exemplified that the lack of temporal information would lead to the dislocation of niche modeling for migratory species represented by spotted *** should be paid to protecting small and migratory populations in marine biodiversity conservation planning.

关键词： conservation priority area marine protected area migration seasonal management spotted seal

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A demand forecasting model for urban air mobility in Chengdu,China

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Green Energy and Intelligent Transportation 2024年第3期3卷 11-23页

作者： Wenqiu Qu Jie Huang Chenglong Li Xiaohan Liao State Key Laboratory of resources and Environment Information System Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China College of resources and Environment University of Chinese Academy of SciencesBeijing 100101China Key Laboratory of Regional Sustainable Development Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China Civil Aviation Flight University of China Guanghan618307China The Research Center for UAV Applications and Regulation CASBeijing 100101China

The successful application of new technologies such as remotely piloted aircraft systems,distributed electric propulsion systems,and automatic control systems on electric vertical take-off and landing(eVTOL)aircraft has prompted Urban Air Mobility(UAM)to be mentioned *** is a newly raised transport mode of using eVTOL aircraft to transport people and cargo in urban areas,which is thought to share some of the traffic on the *** of the prerequisites for UAM to operate on a regular basis is that its demand can support the operating costs,so forecasting UAM demand is *** conduct UAM demand forecasting based on the four-step method,focusing on improving the third-step modal split,and propose a demand forecasting model based on the logit *** model combines a nested logit(NL)model with a multinomial logit(MNL)model to solve the problem of non-existent UAM sharing *** use Chengdu,China as an example,and focus on forecasting the UAM traffic demand in 2030 with the help of the four-step *** results show that UAM is suitable for shared operation during the early *** a fully shared operation,the UAM share rate increases by 0.73%for every kilometer increase in ***,UAM is more competitive than other modes for delivery distances exceeding 15 ***,using the distributions of the share rate and traffic flow pattern from the simulation,we propose the routes that can be prioritized for UAM operations in Chengdu.

关键词： Urban air mobility Four-step method Demand forecasting Logit model Share rate

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Integrating phosphorus management and cropping technology for sustainable maize production

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Journal of Integrative Agriculture 2024年第4期23卷 1369-1380页

作者： Haiqing Gong Yue Xiang Jiechen Wu Laichao Luo Xiaohui Chen Xiaoqiang Jiao Chen Chen State Key Laboratory of Nutrient Use and management College of Resources and Environmental SciencesCollege of Resources and Environmental SciencesChina Agricultural UniversityBeijing 100193China Department of Sustainable Development Environmental Science and Engineering(SEED)KTH Royal Institute of TechnologyStockholm SE-10044Sweden Anhui Province Key Lab of Farmland Ecological Conservation and Pollution Prevention School of Resources and EnvironmentAnhui Agricultural UniversityHefei 230036China Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering National Observations and Research Station for Wetland Ecosystems of the Yangtze EstuaryInstitute of Biodiversity Science and Institute of Eco-ChongmingCollege of Life SciencesFudan UniversityShanghai 200438China

Achieving high maize yields and efficient phosphorus(P)use with limited environmental impacts is one of the greatest challenges in sustainable maize *** plant density is considered an effective approach for achieving high maize ***,the low mobility of P in soils and the scarcity of natural P resources have hindered the development of methods that can simultaneously optimize P use and mitigate the P-related environmental footprint at high plant *** this study,meta-analysis and substance flow analysis were conducted to evaluate the effects of different types of mineral P fertilizer on maize yield at varying plant densities and assess the flow of P from rock phosphate mining to P fertilizer use for maize production in China.A significantly higher yield was obtained at higher plant densities than at lower plant *** application of single superphosphate,triple super-phosphate,and calcium magnesium phosphate at high plant densities resulted in higher yields and a smaller environmental footprint than the application of diammonium phosphate and monoammonium *** scenario analyses suggest that combining the optimal P type and application rate with a high plant density could increase maize yield by 22%.Further,the P resource use efficiency throughout the P supply chain increased by 39%,whereas the P-related environmental footprint decreased by 33%.Thus,simultaneously optimizing the P type and application rate at high plant densities achieved multiple objectives during maize production,indicating that combining P management with cropping techniques is a practical approach to sustainable maize *** findings offer strategic,synergistic options for achieving sustainable agricultural development.

关键词： maize plant density mineral phosphorus fertilizer meta-analysis substance flow analysis

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From Finnish Assortment Pricing to Market Economy Using Prices for Sawn Wood and Chips in Reference Bucking

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Open Journal of Forestry 2024年第3期14卷 233-280页

作者： Juha Lappi faculty of Environmental Sciences and natural Resource management Norwegian University of Life Sciences s Norway

Dominant Finnish assortment pricing gives prices for sawlog and pulp wood volumes. Buyers buck stems to sawlogs using secret price matrices. Agreed dimensions allow wide range of sawlog volumes. Forest owners cannot objectively compare biddings: timber trade is a lottery game. Bucking is analyzed in terms of sawlog, pulp wood, log cylinder, sawn wood, value-weighted sawn wood, and chips. Sawn wood and its value are computed from top diameter of the sawlog. Profit maximization requires buyers to buck logs producing smaller than maximal value, causing dead weight loss. Nominal assortment prices have unpredictable relation to effective stumpage price. Assortment pricing does not meet requirements of market economy. If sawmills linked to pulp mills buck smaller sawlog percentages than independent sawmills, as generally believed, they use higher price for chips in their own harvests than they pay for independent sawmills, indicating imperfect competition for chips. Sawn wood potential pricing is suggested which gives prices for sawn wood and chips coming both from sawlogs and pulp wood in reference bucking which maximizes sawn wood for given minimum and maximum log length and minimum top diameter. Simple algorithm generates feasible bucking schedules from which optimum can be selected using any objective. Pricing produces unit price for all commercial wood utilizing ratio of theoretical sawn wood and commercial volume in stand. Unit price can be compared to stem pricing and could be compared to assortment pricing if assortment pricing would produce predictable sawlog percentages. Sawn wood potential pricing is concrete, transparent, easy to compute, considers stem size and tapering, reduces trading cost and is less risky to buyers than stem pricing. It meets requirements of market economy. Readers can repeat computations using open-source software Jlp22.

关键词： Sawmill Pulp Mill Jlp22 Dead Weight Loss Stem Price

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Optimized NPK fertilizer recommendations based on topsoil available nutrient criteria for wheat in drylands of China

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Journal of Integrative Agriculture 2024年第7期23卷 2421-2433页

作者： Wenjie Yang Jie Yu Yanhang Li Bingli Jia Longgang Jiang Aijing Yuan Yue Ma Ming Huang Hanbing Cao Jinshan Liu Weihong Qiu Zhaohui Wang Key Laboratory of Plant Nutrition and Agri-environment in Northwest China Ministry of Agriculture and Rural Affairs/College of Natural Resources and EnvironmentNorthwest A&F UniversityYangling 712100China

The optimized management of crop fertilization is very important for improving crop yield and reducing the consumption of chemical *** nutrient values can be used for evaluating the nutritional status of a crop,and they reflect the nutrient concentrations above which the plant is sufficiently supplied for achieving the maximum potential *** on on-farm surveys of 504 farmers and 60 field experimental sites in the drylands of China,we proposed a recommended fertilization method to determine nitrogen(N),phosphorus(P),and potassium(K)fertilizer input rates for wheat production,and then validated the method by a field experiment at 66 different sites in northern *** results showed that wheat grain yield varied from 1.1 to 9.2 t ha^(-1),averaging 4.6 t ha^(-1),and it had a quadratic relationship with the topsoil(0-20 cm)nitrate N and soil available P contents at ***,yield was not correlated with the inputs of N,P,and K *** on the relationship(exponential decay model)between 95–105%of the relative yield and topsoil nitrate N,available P,and available K contents at wheat harvest from 60 field experiments,the topsoil critical nutrient values were determined as 34.6,15.6,and 150 mg kg^(-1)for soil nitrate N,available P,and available K,***,based on five groups of relative yield(>125%,115–125%,105–115%,95–105%,and<95%)and the model,the five groups of topsoil critical nutrient levels and fertilization coefficients(Fc)were ***,we proposed a new method for calculating the recommended fertilizer input rate as:Fr=Gy×Nr×Fc,where Fr is the recommended fertilizer(N/P/K)input rate;Gy is the potential grain yield;Nr is the N(N_(rN)),P(N_(rP)),and K(N_(rK))nutrient requirements for wheat to produce 1,000 kg of grain;and Fc is a coefficient for N(N_c)/P(P_c)/K(K_c)fertilizer.A 2-year validated experiment confirmed that the new method reduced N fertilizer input by 17.5%(38.5 kg N ha^(-1))and P fertilizer i

关键词： fertilization method dryland wheat soil nutrient critical value soil nitrogen topsoil nutrients

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A generalized nonlinear three-dimensional Hoek‒Brown failure criterion

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第8期16卷 3149-3164页

作者： Jiaxin Wang Shunchuan Wu Haiyong Cheng Junlong Sun Xiaolong Wang Yaxi Shen faculty of Land Resource Engineering Kunming University of Science and TechnologyKunming650093China Key Laboratory of Geohazard Forecast and Geoecological Restoration in Plateau Mountainous Area Ministry of Natural ResourcesKunming650093China Yunnan Key Laboratory of Geohazard Forecast and Geoecological Restoration in Plateau Mountainous Area Kunming650093China

To understand the strengths of rocks under complex stress states,a generalized nonlinear threedimensional(3D)Hoek‒Brown failure(NGHB)criterion was proposed in this *** criterion shares the same parameters with the generalized HB(GHB)criterion and inherits the parameter advantages of *** new parameters,b,and n,were introduced into the NGHB criterion that primarily controls the deviatoric plane shape of the NGHB criterion under triaxial tension and compression,*** NGHB criterion can consider the influence of intermediate principal stress(IPS),where the deviatoric plane shape satisfies the smoothness requirements,while the HB criterion *** criterion can degenerate into the two modified 3D HB criteria,the Priest criterion under triaxial compression condition and the HB criterion under triaxial compression and tension *** criterion was verified using true triaxial test data for different parameters,six types of rocks,and two kinds of in situ rock *** comparison,three existing 3D HB criteria were selected for performance comparison *** result showed that the NGHB criterion gave better prediction performance than other *** prediction errors of the strength of six types of rocks and two kinds of in situ rock masses were in the range of 2.0724%-3.5091%and 1.0144%-3.2321%,*** proposed criterion lays a preliminary theoretical foundation for prediction of engineering rock mass strength under complex in situ stress conditions.

关键词： Rock mechanics HoekeBrown criterion Failure criterion Intermediate principal stress True triaxial test Smoothness and convexity

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