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Spatial Distribution Assessment and Source Apportionment of Land-Based Pollutant Yield from Qingdao, China 被引量:1
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作者 SU Ying LIANG Shengkang +1 位作者 ZHANG Peng WANG Xiulin 《Journal of Ocean University of China》 SCIE CAS CSCD 2019年第1期151-158,共8页
The spatial distribution of chemical oxygen demand(COD) and total nitrogen(TN) yield from Qingdao are studied by comparing pollutant yield amount, densities and spatial aggregation(Getis-Ord indexes) among the land-ba... The spatial distribution of chemical oxygen demand(COD) and total nitrogen(TN) yield from Qingdao are studied by comparing pollutant yield amount, densities and spatial aggregation(Getis-Ord indexes) among the land-based pollutant source regions(PSRs) entering the three sub-seas(i.e. the Jiaozhou Bay(JZB), other coastal area in the Yellow Sea(OCAYS) and Laizhou Bay(LZB), respectively). Industrial composition of the loads are also studied by comparing pollutant yield among the sources of agriculture, rural domesticity, industry, urban domesticity and service, and calculation of Gini coefficient. Results show that spatial distribution of COD and TN yield from Qingdao are extremely unbalanced. The JZB, with less than 3% of the total coastal sea area of Qingdao, received 62% COD load and 65% TN yield from Qingdao, while the OCAYS, with more than 97% area, only received 23% COD and 20% TN, which consist with the much worsen water quality of JZB than that of OCAYS. On the other hand, the source apportionment of COD and TN loads in the PSRs entering JZB and the OCAYS was similar. The agricultural and domestic sources with high pollution intensity account for more than 80%, while the industrial and service sources with low pollution intensity account for less than 20%. While Gini coefficients, COD 0.81 and TN 0.84 which are much higher than the ‘imbalance' threshold of 0.4, show the uneven industrial structure of Qingdao. These results may be useful in the determination of land-based pollution total amount control at the PSR level. 展开更多
关键词 Qingdao land-based POLLUTANT POLLUTANT YIELD POLLUTION INTENSITY industrial structure
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Unsustainable Land-Based Source Pollution in a Climate of Change: A Roadblock to the Conservation and Recovery of Elkhorn Coral <i>Acropora palmata</i>(Lamarck 1816) 被引量:1
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作者 Geraldine Díaz-Ortega Edwin A. Hernández-Delgado 《Natural Resources》 2014年第10期561-581,共21页
Chronic eutrophication and turbidity are critical detrimental factors impacting coral reef ecosystems, adversely affecting their ecological functions, services, benefits, and resilience across multiple spatial scales ... Chronic eutrophication and turbidity are critical detrimental factors impacting coral reef ecosystems, adversely affecting their ecological functions, services, benefits, and resilience across multiple spatial scales and over prolonged periods of time. Inadequate land use practices and lack of appropriate sewage treatment can adversely contribute to increase land-based source pollution (LBSP) impacts in coastal waters and to magnify impacts by sea surface warming trends associated to climate change. Fringing coral reefs off Vega Baja, Puerto Rico, support extensive remnant patches of Elkhorn coral Acropora palmata (Lamarck 1816), which was listed in 2006 as a threatened species under the US Endangered Species Act. Chronic impacts by LBSP have significantly affected local downstream fringing reefs. We characterized the spatial extent of a water quality stress gradient across 12 reefs along the Vega Baja coast through monthly measurements of multiple physico-chemical parameters. Most parameters, particularly PO4, , chlorophyll-a, and the concentration of optical brighteners (OABs), showed a statistically significant increase (PERMANOVA, p < 0.05) in waters close to the main pollution sources, but also in waters adjacent to Cibuco River effluents. Dissolved oxygen also declined and turbidity increased on polluted sites. PO4, , and chlorophyll-a, exceeded recommended concentrations for coral reef ecosystems by factors of 7 - 50 times, 600 - 1240 times, and 17 - 83 times, respectively, depending on the source of the effluents and the distance from sewage pollution sources. Also, water turbidity exceeded 4 - 10 times the recommended value for pristine coral reefs. Coral reefs showed significant decline in close proximity to the polluted zone, showing a significantly different benthic community structure (PERMANOVA, p < 0.0001) dominated by non-reef building taxa (i.e., macroalgae, algal turf) and bare substrate. Percent coral cover and abundance of A. palmata, showed a significant increase with distance. Coral species richness, species diversity index, and the variance in taxonomic distinctness were very low on reef patches adjacent to the polluted zone, increased at a moderate distance with increasing coral cover and co-existence of multiple species, and declined far from the pollution source due to dominance exerted by A. palmata. This study suggests that chronic LBSP resulted in a major decline of one of the largest and most dense remnant stands of A. palmata across the northeastern Caribbean and that nutrient and chlorophyll-a concentrations were unsustainable for coral reefs. This situation requires immediate solution to prevent further damage to these unprecedented resources. It further suggests that chronic LBSP may synergistically magnify sea-surface warming impacts driving corals to an increased state of risk in face of forecasted climate change impacts. Actions to mitigate and adapt to climate change impacts on coral reefs must require a priori controls of LBSP to be effective. 展开更多
关键词 ACROPORA palmata CORAL REEF Decline Eutrophication land-based Source Pollution
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A land-based tank aquaculture system coupled with effluent treatment ponds:Effect of stocking density on the growth performance of gibel carp(Carassius gibelio)
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作者 Huacheng Li Jieya Liu +14 位作者 Rui Chen Yin Wang Wenhan Li Qiushi Yang Tingting Xu Sayed R.S.Zidan Chengchen Jiang Yutian Yuan Xuxu Li Liqin Yu Rong Tang Chunfang Wang Li Li Xi Zhang Dapeng Li 《Water Biology and Security》 2026年第1期169-183,共15页
Recirculating aquaculture systems(RASs)are recognized for their eco-friendly and efficient approach in aqua-culture.This study constructed a novel system:a land-based tank aquaculture system coupled with effluent trea... Recirculating aquaculture systems(RASs)are recognized for their eco-friendly and efficient approach in aqua-culture.This study constructed a novel system:a land-based tank aquaculture system coupled with effluent treatment ponds(LBTAS).The system includes land-based tanks,an oxygen supply system,a water inlet system,a sewage collection system,and an effluent treatment system.We evaluated the impact of different stocking den-sities on the growth,health,aquaculture yield,and economic benefits of gibel carp(Carassius gibelio)in the LBTAS.The yields of the high stocking density(HSD)group and the low stocking density(LSD)group were similar,which was more than three times that of traditional pond farming.But the LSD group significantly improved final weight(FW),final length(FL),weight gain ratio(WGR),specific growth rate(SGR),feed con-version ratio(FCR),ingestion rate(IR),and viscerosomatic index(VSI)compared to HSD groups(P<0.05).While survival rates and the hepatosomatic index(HSI)were similar across groups,the low-density group exhibited better overall health.Serum biochemical indicators such as glucose(GLU),cholesterol(CHO),alkaline phos-phatase(ALP),and aspartate aminotransferase(AST)were unaffected by density.However,levels of alanine aminotransferase(ALT),triglycerides(TG),lactate acid(LD),and cortisol were significantly higher in the HSD group(P<0.05),indicating increased stress.Hepatic antioxidant analysis showed stable levels of glutathione peroxidase(GSH-PX)and total superoxide dismutase(T-SOD),but higher levels of catalase(CAT)and malon-dialdehyde(MDA)in the high-density group(P<0.05),suggesting increased oxidative stress.Muscle histology analysis revealed significantly higher muscle fiber density in the LSD group(P<0.05),with no significant effect on muscle fiber diameter.Water quality analysis indicated poorer quality in the HSD group,with lower dissolved oxygen and significantly higher concentrations of total phosphorus(TP)and nitrite nitrogen(NO_(2)^(-)·N)compared to the LSD group(P<0.05).Despite the initial lower cost,the LSD group achieved a higher economic return on investment(ROI)of 16.92%.Our research results demonstrate that the aquaculture yield of gibel carp in the LBTAS is more than three times that of traditional ponds,with a return on investment reaching up to 16.92%.However,the HSD can negatively impact the growth performance,health status,and economic benefit of gibel carp.These results preliminary confirm the feasibility of the LBTAS,highlighting the importance of balanced aquaculture practices for sustainability and profitability. 展开更多
关键词 Aquaculture yield Carassius gibelio Economic benefit land-based tank Stocking density
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拒绝服务攻击的原理及防范技术
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作者 赵皖平 《中国金融电脑》 2004年第5期61-64,共4页
关键词 拒绝服务攻击 互联网 防范技术 DOS攻击 服务器端资源 land-based PING of DEATH Smurf Trinoo 分布式反射拒绝服务 TCP/IP协议
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Precise Emission Reduction of Total Nitrogen for Jurisdictions in Laizhou Bay,China:A Simulation-Optimization Approach Linking Land-Sea Management
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作者 WANG Yan ZHONG Shimin +4 位作者 SU Ying SUN Mingdong WENG Qiaoran XU Xiangqin LEI Kun 《Journal of Ocean University of China》 SCIE CAS CSCD 2024年第6期1534-1550,共17页
This study aims to provide a quantitative basis for the precision emission reduction of land-based total nitrogen(TN)pollutants in Laizhou Bay(LZB),China.The total maximum allocated load(TMAL)of TN pollutants within j... This study aims to provide a quantitative basis for the precision emission reduction of land-based total nitrogen(TN)pollutants in Laizhou Bay(LZB),China.The total maximum allocated load(TMAL)of TN pollutants within jurisdictions around LZB was calculated using the stepwise simulation-optimization model after the division of source units,simulation of the concentration response matrix,setting of the additional constraint conditions for stepwise source units,and calculation of TMAL.The load reduction allocation system for jurisdictions can be constructed on the basis of the TMAL and the load monitored or statistics.The index system for TN emission reduction included indices for two groups:a fixed index of marine emission reduction rate for jurisdictions,which was 11.93%on average;and threshold indices of pollution prevention rate at sources,the increment rate of pollution removal by municipal sewage treatment systems,and watershed retention of jurisdictions,which were 7.43%,1.58%,and 1.09%on average,respectively.Efficiency of pollutant reduction can be evaluated using a 3D hydrodynamic-water quality model.Simulation results showed that the precise reduction indicators achieved the seawater quality improvement target of LZB 5 years earlier than the equal proportion reduction indicators currently used in LZB Basin. 展开更多
关键词 Laizhou Bay land-based total nitrogen total maximum allocated load land-sea management
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Cybersecurity for Allied Future Submarines
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作者 Keith F. Joiner Simon Reay Atkinson +1 位作者 Pete Christensen Elena Sitnikova 《World Journal of Engineering and Technology》 2018年第4期696-712,共17页
Cyber has become a supposedly cheap first-strike weapon of political choice by potential adversaries in a milieu placing insurgency, terrorism, international crime and state-based influences in close un-regulated prox... Cyber has become a supposedly cheap first-strike weapon of political choice by potential adversaries in a milieu placing insurgency, terrorism, international crime and state-based influences in close un-regulated proximity. The merging of electronic and cyber warfare means that not even submarines, however unconnected or firewalled they may be, are immune. The quantum attack surface of submarines is as much in their past, as they are in their designs today and their operations tomorrow: they must survive to be credible and ideally they should even be a contemporary offensive cyber deterrent. Such critical defensive systems require robust security systems engineering and cybersecurity test and evaluation to build and sustain their cyber-resilience. This paper uses Australia’s future submarine program [1]1 to outline key facets needed in a submarine program to achieve cyber resilience, including how to adapt U.S. Department of Defense (DoD) best practices to engineer, test and sustain cyber-resilient submarine systems. Strategies are needed that provision sovereign-owned and operated land-based test sites to design, build, demonstrate and sustain critical submarine systems. This work is most relevant to countries allied to the U.S. and importing submarine capabilities, such as within lesser European powers and also in the Indo-Pacific where both cyber warfare and submarines are proliferating. 展开更多
关键词 Cyber-Resilience FUTURE SUBMARINE Design land-based TEST Sites Quantum Attack Surface TEST and Evaluation
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Growth,antioxidant activity and mineral profile of Chaetomorpha linum(O.F.Müller)Kützing(1845)cultured in potassium deficient media
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作者 Joel Wynhorst Wing Huen Chung +1 位作者 Ravi Fotedar Janet Howieson 《Food Bioscience》 2025年第1期1658-1667,共10页
The value of seaweed based pharmaceutical products has drastically increased in the past decade.Chaetomorpha linum(Chlorophyta)extract has been described to have a high level of antioxidants and bioactive compounds,ho... The value of seaweed based pharmaceutical products has drastically increased in the past decade.Chaetomorpha linum(Chlorophyta)extract has been described to have a high level of antioxidants and bioactive compounds,however it is unknown how growth conditions,specifically the ionic profile of its culture media,may impact C.linum’s biochemical profile.This study tested growth,antioxidant activity,chlorophyll and mineral profile following culture in a 2×2 factorial methodology,with water type(inland saline water[ISW]or ocean water[OW])and nutrient enrichment(nitrate and phosphate)as co-factors.C.linum was cultivated for 20 days outdoors and fresh weight was recorded every five days.On day 10,50 g of seaweed was harvested,and mineral analysis and ultrasound-assisted extraction were performed.Extracts were tested for antioxidant activity and chlorophyll content.Antioxidant activity was not significantly different across treatments in ferric reducing antioxidant potential and total phenolic content assays,though specific growth rate was lower in ISW than OW treatments.Calcium content(mg.g^(-1) d.b.)was also significantly higher(p<0.001)in ISW than OW.This study found that short-term growth of C.linum in ISW can increase calcium content while maintaining the efficacy of its bioactive profile,presenting a new method for producing a mineral rich food or health supplement for human consumption. 展开更多
关键词 Human nutrition Inland saline water land-based cultivation Nutraceuticals Seaweed
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Weighted spectral correlation angle target detection method for land‑based hyperspectral imaging 被引量:1
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作者 Qianghui Wang Bing Zhou +3 位作者 Wenshen Hua Jiaju Ying Xun Liu Yue Cheng 《Frontiers of Optoelectronics》 EI CSCD 2023年第4期121-134,共14页
In land-based spectral imaging,the spectra of ground objects are inevitably afected by the imaging conditions(weather conditions,atmospheric conditions,light conditions,zenith and azimuth angle conditions)and spatial ... In land-based spectral imaging,the spectra of ground objects are inevitably afected by the imaging conditions(weather conditions,atmospheric conditions,light conditions,zenith and azimuth angle conditions)and spatial distribution of targets,leading to uncertainties featured by“same object diferent spectrum”.That is,the spectrum of a ground object may change within a certain range under diferent imaging conditions.Traditional target detection(TD)methods are mainly based on similarity measurements and do not fully account for the spectral uncertainties.These detection methods are prone to false detections or missed detections.Therefore,reducing the impact of spectral uncertainties on TD is an important research topic in hyperspectral imaging.In this paper,we frst review traditional TD methods and compare their principles and characteristics.It is found that the spectral correlation angle(SCA)method has good adaptability in land-based imaging.The shortcoming of the SCA method that it cannot refect the local spectrum characteristics,is also analyzed.As the efect of spectral uncertainties cannot be completely overcome by the SCA method,a new similarity measurement method,the weighted spectral correlation angle(WSCA)method,is proposed.It can reduce the infuence of spectral uncertainties on TD by increasing the weight of particular bands.Finally,we use two sets of experiments to analyze the efect of the WSCA method on TD.Its performance in overcoming spectral uncertainties caused by variations in imaging conditions or uneven spatial distributions of targets is tested.The results show that the WSCA method can efectively reduce the infuence of spectral uncertainties and obtain a good detection result. 展开更多
关键词 Hyperspectral image Spectral uncertain feature Target detection land-based imaging condition Weighted spectral correlation angle(WSCA)
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