Investigating factors driving phytoplankton growth and grazing loss rates in waters around Peninsular Malaysia     

Lim  Joon Hai  Lee  Choon Weng  Bong  Chui Wei 《中国海洋湖沼学报》2021,39(1):148-159

In tropical waters where temperatures are relatively stable,we investigated whether the relationship between phytoplankton growth and grazing loss rate acros s different habitats around Peninsular Malaysia can be attributed to its eutrophication states.We measured phytoplankton growth(μ) and grazing loss(g) rates in waters off Bachok Marine Research Station(BMRS),located northeast of Peninsular Malaysia.Chlorophyll-a(chl-a) concentration ranged from 2.90 to 15.78 μg/L and was dominated by nanoand micro-phytoplankton(2 μm in size).Using the Landry and Hassett dilution method,μ at BMRS ranged from 1.02 to 1.58/d whereas g varied from 0.07 to 0.88/d.Grazing accounted for 35% of the primary production at BMRS.A systematic review of available data in waters around Peninsular Malaysia,revealed how μ fluctuated over a wide range(0.01-1.80/d) and correlated with chl a distribution(R2=0.181,P0.001).However,the relationship was only significant at 9 μg/L chl a for mesotrophic waters and 16 μg/L chl a for eutrophic waters.In contrast,g ranged from 0.00 to 1.01/d,and correlated with μ at all locations.The g/μslope ranged from 19% to 84%,and was generally similar for waters around Peninsular Malaysia.However,all the g/μ slopes had a positive y-intercept except for BMRS,and this seemed to suggest the availability of alternative prey supporting grazing at the other stations.  相似文献   

Lensing by galaxies in CNOC2 fields     

H. Hoekstra  M. Franx  K. Kuijken  R. G. Carlberg †  H. K. C. Yee † 《Monthly notices of the Royal Astronomical Society》2003,340(2):609-622

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Staying cool in a changing climate: Reaching vulnerable populations during heat events   总被引：1，自引：0，他引：1  

Natalie R. Sampson  Carina J. Gronlund  Miatta A. Buxton  Linda Catalano  Jalonne L. White-Newsome  Kathryn C. Conlon  Marie S. O’Neill  Sabrina McCormick  Edith A. Parker 《Global Environmental Change》2013,23(2):475-484

The frequency and intensity of hot weather events are expected to increase globally, threatening human health, especially among the elderly, poor, and chronically ill. Current literature indicates that emergency preparedness plans, heat health warning systems, and related interventions may not be reaching or supporting behavior change among those most vulnerable in heat events. Using a qualitative multiple case study design, we comprehensively examined practices of these populations to stay cool during hot weather (“cooling behaviors”) in four U.S. cities with documented racial/ethnic and socio-economic disparities and diverse heat preparedness strategies: Phoenix, Arizona; Detroit, Michigan; New York City, New York; and Philadelphia, Pennsylvania. Based on semi-structured in-depth interviews we conducted with 173 community members and organizational leaders during 2009–2010, we assessed why vulnerable populations do or do not participate in health-promoting behaviors at home or in their community during heat events, inquiring about perceptions of heat-related threats and vulnerability and the role of social support. While vulnerable populations often recognize heat's potential health threats, many overlook or disassociate from risk factors or rely on experiences living in or visiting warmer climates as a protective factor. Many adopt basic cooling behaviors, but unknowingly harmful behaviors such as improper use of fans and heating and cooling systems are also adopted. Decision-making related to commonly promoted behaviors such as air conditioner use and cooling center attendance is complex, and these resources are often inaccessible financially, physically, or culturally. Interviewees expressed how interpersonal, intergenerational relationships are generally but not always protective, where peer relationships are a valuable mechanism for facilitating cooling behaviors among the elderly during heat events. To prevent disparities in heat morbidity and mortality in an increasingly changing climate, we note the implications of local context, and we broadly inform heat preparedness plans, interventions, and messages by sharing the perspectives and words of community members representing vulnerable populations and leaders who work most closely with them.  相似文献   

Constraining and enabling factors to using long-term climate information in decision-making     

Lindsey Jones  Clara Champalle  Sabrina Chesterman  Laura Cramer  Todd A. Crane 《Climate Policy》2013,13(5):551-572

We carry out a structured review of the peer-reviewed literature to assess the factors that constrain and enable the uptake of long-term climate information in a wide range of sectoral investment and planning decisions. Common applications of long-term climate information are shown to relate to urban planning and infrastructure, as well as flood and coastal management. Analysis of the identified literature highlights five categories of constraints: disconnection between users and producers of climate information, limitations of climate information, financial and technical constraints, political economy and institutional constraints and finally psycho-social constraints. Five categories of enablers to the uptake of long-term climate information in decision-making are also identified: collaboration and bridge work, increased accessibility of climate information, improvement in the underlying science, institutional reform and windows of opportunity for building trust.

Policy relevance

Our review suggests that stand-alone interventions aimed at promoting the uptake of climate information into decision-making are unlikely to succeed without genuine and sustained relationships between producers and users. We also highlight that not every decision requires consideration of long-term climate information for successful outcomes to be achieved. This is particularly the case in the context of developing countries, where the immediacy of development challenges means that decision makers often prioritize short-term interventions. Care should therefore be taken to ensure that information is targeted towards investments and planning decisions that are relevant to longer-term timescales.  相似文献   

Characterization and utilization of noisy displacement signals from simple shear device using linear and kernel regression methods     

Eric Yee  Jonathan P. Stewart  Frederic P. Schoenberg 《Soil Dynamics and Earthquake Engineering》2011

Small strain testing of dynamic soil properties such as threshold strains, γ_tv, are often conducted using specialized devices such as dual-specimen simple-shear, as devices configured for large strain testing produce noisy signals in the small strain range. Working with a simple shear device originally developed for large-strain testing, we extend its low-strain capabilities by characterizing noisy signals and utilizing several statistical methods to extract meaningful responses in the small strain range. We utilize linear regression of a transformed variable to estimate the cyclic shear strain from a noisy signal and the confidence interval on its amplitude. We utilize Kernel regression with the Nadaraya–Watson estimator and a Gaussian kernel to evaluate vertical strain response. A practical utilization of these techniques is illustrated by evaluating threshold shear strains for volume change with a procedure that takes into account uncertainties in the measured shear and vertical strains.  相似文献   

Characterization of acid river dilution and associated trace element behavior through hydrogeochemical modeling: A case study of the Banyu Pahit River in East Java, Indonesia     

Stephanie C.J. PalmerVincent J. van Hinsberg  Jeffrey M. McKenzie  Sophia Yee 《Applied Geochemistry》2011,26(11):1802-1810

Kawah Ijen volcano in East Java, Indonesia emits hyperacid (pH ≈ 0) brines rich in toxic elements including F, Al, Cd and Tl, which are transported downstream by the Banyu Pahit River, which is eventually used to irrigate farmland on the Asambagus Plain. The fate and behavior of major and trace elements are investigated, in the region of greatest change to the Banyu Pahit River, where thermal springs and the neutral Kali Sat and Kali Senggon Rivers increase its discharge 6-fold and pH increases from 1.9 to 4.5 with the development of abundant precipitates. The conservative behavior of Cl, F and SO₄ allows determination of the proportions of the mixing constituents at each confluence. Comparing a mass balance model based on the resulting proportions with measured concentrations demonstrates conservative behavior for most cations, with the exception of Si, Zr, Sn and Ba, which precipitate as amorphous silica, barite, and Zr and Sn phases, respectively. Iron is added as particulate Fe-(oxy)hydroxide in mixing with thermal spring outflow, and dissolves in the lower pH water. This also contributes Co, Cd, Mn, Y, and the rare earth elements, which are desorbed from the Fe-(oxy)hydroxide upon entering the acid water. Subsequent saturation in Fe-(oxy)hydroxide after mixing with the neutral rivers leads to a reverse response. Still, element behavior is close to conservative, which means that the volcanogenic toxic element load is almost entirely transferred to the Asambagus Plain with ensuing environmental and health impacts. This study shows that compositions of these acid waters can be understood and reproduced in a thermodynamic model, but only when fine-tuned using measured compositions and field observations. Therefore, the model’s utility in assessing the fate of toxic elements and in planning the environmental mitigation is limited.  相似文献   

Detection of crossover time scales in multifractal detrended fluctuation analysis     

Erjia Ge  Yee Leung 《Journal of Geographical Systems》2013,15(2):115-147

Fractal is employed in this paper as a scale-based method for the identification of the scaling behavior of time series. Many spatial and temporal processes exhibiting complex multi(mono)-scaling behaviors are fractals. One of the important concepts in fractals is crossover time scale(s) that separates distinct regimes having different fractal scaling behaviors. A common method is multifractal detrended fluctuation analysis (MF-DFA). The detection of crossover time scale(s) is, however, relatively subjective since it has been made without rigorous statistical procedures and has generally been determined by eye balling or subjective observation. Crossover time scales such determined may be spurious and problematic. It may not reflect the genuine underlying scaling behavior of a time series. The purpose of this paper is to propose a statistical procedure to model complex fractal scaling behaviors and reliably identify the crossover time scales under MF-DFA. The scaling-identification regression model, grounded on a solid statistical foundation, is first proposed to describe multi-scaling behaviors of fractals. Through the regression analysis and statistical inference, we can (1) identify the crossover time scales that cannot be detected by eye-balling observation, (2) determine the number and locations of the genuine crossover time scales, (3) give confidence intervals for the crossover time scales, and (4) establish the statistically significant regression model depicting the underlying scaling behavior of a time series. To substantive our argument, the regression model is applied to analyze the multi-scaling behaviors of avian-influenza outbreaks, water consumption, daily mean temperature, and rainfall of Hong Kong. Through the proposed model, we can have a deeper understanding of fractals in general and a statistical approach to identify multi-scaling behavior under MF-DFA in particular.  相似文献   

Mobility encounter: The narratives of Burmese refugees in Norway     

Yee Yee Swe 《Norsk geografisk tidsskrift. Norwegian journal of geography》2013,67(4):229-238

The article examines the lived experiences of Burmese refugees in Norway in order to understand how they experience integration into local society and how they manage their transnational lives in new socio-economic, political, and cultural contexts. The examination is performed from the perspective of mobility as the entanglement of movement, representation, and practice. In teasing out the refugees' various experiences, the author emphasizes the diversity of migrant groups in terms of their ethnicity, religion, gender, and age, as well as multiple dimensions of mobilities. The complex politics of mobility – how different mobilities are produced, practised, and regulated in relation to issues such as transnational migration, diasporic cultures, and communication technologies – is seen as underlying the narratives of Burmese refugees in Norway. Their narratives equate mobilities with escape from poverty, highlighting the linkage that mobility has with poverty and development. The discussion reveals the potential for divisiveness within wider society in Norway, and it is argued that a nuanced understanding of how mobilities are differentially accessed within immigrant groups is essential for conceiving a multicultural society in Norway.  相似文献   

加州地震概率预测将对地震学理论产生强烈震动     

Glennda Chui  左玉玲 《国际地震动态》2010,(8):1-5

地质断层的运动模式与科学家曾经预期的并不相同。目前,科学家试图对地震的活动习性形成全新的认识,Glennda Chui对此进行了报道。  相似文献   

Groundwater Governance in the United States: Common Priorities and Challenges          下载免费PDF全文

Sharon B. Megdal  Andrea K. Gerlak  Robert G. Varady  Ling‐Yee Huang 《Ground water》2015,53(5):677-684

Groundwater is a critical component of the water supply for agriculture, urban areas, industry, and ecosystems, but managing it is a challenge because groundwater is difficult to map, quantify, and evaluate. Until recently, study and assessment of governance of this water resource has been largely neglected. A survey was developed to query state agency officials about the extent and scope of groundwater use, groundwater laws and regulations, and groundwater tools and strategies. Survey responses revealed key findings: states' legal frameworks for groundwater differ widely in recognizing the hydrologic connection between surface water and groundwater, the needs of groundwater‐dependent ecosystems, and the protection of groundwater quality; states reported a range in capacity to enforce groundwater responsibilities; and states have also experienced substantial changes in groundwater governance in the past few decades. Overall, groundwater governance across the United States is fragmented. States nevertheless identified three common priorities for groundwater governance: water quality and contamination, conflicts between users, and declining groundwater levels. This survey represents an initial step in a broader, continuing effort to characterize groundwater governance practices in the United States.  相似文献