Biomass Spectra of Aquatic Ecosystems in Relation to Fisheries Yield

1992 ◽  
Vol 49 (8) ◽  
pp. 1528-1538 ◽  
Author(s):  
P. R. Boudreau ◽  
L. M. Dickie
Keyword(s):  
Body Size ◽  
Aquatic Ecosystems ◽  
Detailed Data ◽  
Biomass Density ◽  
Short Term ◽  
The World ◽  
Long Term Changes ◽  
Biomass Spectra

The biomass density of aquatic ecosystems can be expressed as an allometric function of organism body size. The log–log plot of this relation, termed the biomass spectrum, is used to compare aquatic ecosystems in various parts of the world. We develop a standardized presentation for several example environments where detailed data on biomass density by body size in the trophic positions, phytoplankton, zooplankton, benthos, and fish, make it possible to establish overall or primary spectral slopes. The basic methodology is adapted for application to other ecosystems where less detailed data are available. Spectra from all the different environments exhibit a uniform low slope, but with different intercepts that appear to reflect ecosystem differences in nutrient circulation and availability. Detail on the secondary structuring at various positions in the trophic system appears to provide information useful for distinguishing between long-term changes in productivity and short-term perturbations in biomass or abundance.

The Long-term Use of Short-term Debt around the World

2019 ◽  
Author(s):  
Lifang Chen ◽  
Yong Li ◽  
Yizhong Wang ◽  
Bohui Zhang
Keyword(s):  
Short Term ◽  
The World

scholarly journals Long-Term Changes in the Diet of Gymnogobius isaza from Lake Biwa, Japan: Effects of Body Size and Environmental Prey Availability

PLoS ONE ◽  
2012 ◽  
Vol 7 (12) ◽  
pp. e53167 ◽  
Author(s):  
Jonathan Carlo Briones ◽  
Cheng-Han Tsai ◽  
Takefumi Nakazawa ◽  
Yoichiro Sakai ◽  
Rey Donne S. Papa ◽  
...  
Keyword(s):  
Body Size ◽  
Lake Biwa ◽  
Prey Availability ◽  
Long Term Changes

Short-Term and Long-Term Changes of Left Ventricular Volumes During Rate-Adaptive and Single-Rate Pacing

1989 ◽  
Vol 12 (12) ◽  
pp. 1863-1868 ◽  
Author(s):  
MEREDITH I. SEDNEY ◽  
ERIC WEIJERS ◽  
ERNST E. WALL ◽  
JEEEREY D. ADIPRANOTO ◽  
JAN CAMPS ◽  
...  
Keyword(s):  
Left Ventricular ◽  
Left Ventricular Volumes ◽  
Short Term ◽  
Ventricular Volumes ◽  
Long Term Changes ◽  
Rate Adaptive

scholarly journals On the peculiarities in the spin-down of isolated radio pulsars

2012 ◽  
Vol 8 (S291) ◽  
pp. 208-208
Author(s):  
Augustine Chukwude
Keyword(s):  
Radio Astronomy ◽  
Time Resolution ◽  
Local Phase ◽  
Astronomy Observatory ◽  
Radio Pulsars ◽  
Short Term ◽  
Radio Astronomy Observatory ◽  
Long Term Changes ◽  
Timing Data

AbstractWe investigate the spin-down behaviour of a sample of 25 radio pulsars on decadal timescales (~ 18 years) using a continuous timing data obtained over a period of at Hartebeesthoek Radio Astronomy Observatory (HartRAO). Particular attention is placed on achieving a better time resolution of both the short-term and long-term changes in pulsar spin-down using local phase-coherent measurements of the spin-down rates (). We demonstrate that the spin-down of radio pulsars is generally complicated by a superposition of processes that may or may not be related. Specifically, our results show that (i) for 7 pulsars, the observed spin-down variation is largely stochastic, characterized by random and sustained jumps in of varying amplitudes, (ii) for 9 objects, the spin-down evolution shows dominant monotonic variations in superimposed on short-term stochastic jumps in the parameter, and (iii) for the remaining 9 pulsars, the long-term spin-down evolution is non-monotonic, dominated by some systematic excursion in the measured spin-down rates.

scholarly journals From hierarchies to markets and partially back again in electricity: responding to decarbonization and security of supply goals

2021 ◽  
pp. 1-17
Author(s):  
Paul L. Joskow
Keyword(s):  
Market Integration ◽  
Investment Incentives ◽  
Wholesale Market ◽  
Security Of Supply ◽  
Short Term ◽  
Institutional Adaptation ◽  
The World ◽  
New Challenges ◽  
And Storage

Abstract Electric power sectors around the world have changed dramatically in the last 25 years as a result of sector liberalization policies. Many electricity sectors are now pursuing deep decarbonization goals which will entail replacing dispatchable fossil generation primarily with intermittent renewable generation (wind and solar) over the next 20–30 years. This transition creates new challenges for both short-term wholesale market design and investment incentives consistent with achieving both decarbonization commitments and security of supply criteria. Thinking broadly about the options for institutional change from a Williamsonian perspective – thinking like Williamson – provides a useful framework for examining institutional adaptation. Hybrid markets that combine ‘competition for the market’ that relies on competitive procurement for long-term purchased power agreements with wind, solar, and storage developers, ideally in a technology neutral fashion, and ‘competition in the market’ that relies on short-term markets designed to produce efficient and reliable operations of intermittent generation and storage, is identified as a promising direction for institutional adaptation. Many auction, contract, and market integration issues remain to be resolved.

scholarly journals Win-win or unequal exchange? The case of the Sino-Congolese cooperation agreements

2009 ◽  
Vol 47 (3) ◽  
pp. 371-396 ◽  
Author(s):  
Stefaan Marysse ◽  
Sara Geenen
Keyword(s):  
Joint Venture ◽  
Sub Saharan Africa ◽  
Public Infrastructure ◽  
Short Term ◽  
Internal Development ◽  
Unequal Exchange ◽  
The World ◽  
Sub Saharan ◽  
Investment Agreements

ABSTRACTThe recent involvement of China in sub-Saharan Africa is challenging and changing the world geostrategic scene. In the article, we analyse the agreements between the Congolese government and a group of Chinese state-owned enterprises. A number of public infrastructure works will be financed with Chinese loans. To guarantee reimbursement, a Congolese/Chinese joint venture will be created to extract and sell copper, cobalt and gold. These are the biggest trade/investment agreements that China has so far signed in Africa. This article seeks to contribute to the discussion regarding the agreement's impact on internal development in Congo. Does it create a ‘win-win’ situation for all, or is it an unequal exchange? We outline the internal and international debates and analyse several noteworthy characteristics of the agreements. In conclusion, we present a balanced view on the likely impact on Congo's short-term and long-term development.

scholarly journals Long- and Short-Term Changes of the Structure of Macrophytes in Lake Piaseczno in Relation to Land Use in the Łęczna-Włodawa Lakeland (Poland)

2013 ◽  
Vol 15 (2) ◽  
pp. 101-110
Author(s):  
Joana Sender ◽  
Weronika Maślanko
Keyword(s):  
Land Use ◽  
Aquatic Plants ◽  
Short Term ◽  
Main Interest ◽  
Central European ◽  
Macrophyte Communities ◽  
Long Term Changes ◽  
Very High ◽  
Macrophyte Structure

ABSTRACT The Łęczna-Włodawa Plain, known also as the Łęczna-Wlodawa Lakeland, lies within the territory of the largest subregion of the Polesie region, covering over 1,300 km2. The main interest of the Łęczna-Włodawa Lakeland is that it is the oldest in the Central European Lowlands group of about 68 lakes. Among such a large number of lakes there exist all trophic types. However, since the late 1950’s, enormous dynamics of change associated with the disappearance of oligo- and mesotrophic lakes and their transformation into eutrophic, even hypertrophic, lakes have been observed. One of the biocenotic elements of the lakes, which are indicators of these changes, is aquatic plants. The aim of this study was to determine the macrophyte structure of Piaseczno Lake and changes of land use in its surroundings. Piaseczno Lake still represents very high natural values. A reduction in the number of macrophyte communities, which occurred especially in 2008, was a consequence of the fast-growing recreation infrastructure. From 1976 until 2010 an area of recreation infrastructure in the studied area increased more than 3.5 times, and in the built-up area more than five times, as well as a doubling of the total length of the roads. Meanwhile the surface area of wetlands and peatbogs significantly decreased - more than 11 times. Long-term changes in the structure of the macrophyte communities show that the number of communities has varied in each year, probably as a consequence of changes in landuse. Analysis showed changes to the surfaces inhabited by macrophytes, which have decreased significantly over only four years, by more than 25%. However, the proportion of rush communities has increased.

scholarly journals The new structural economics: patient capital as a comparative advantage

2017 ◽  
Vol 1 (1) ◽  
pp. 4 ◽  
Author(s):  
Justin Yifu Lin ◽  
Yan Wang
Keyword(s):  
Comparative Advantage ◽  
World Economy ◽  
Institutional Factors ◽  
Capital Account ◽  
Public Infrastructure ◽  
Short Term ◽  
Capital Account Liberalization ◽  
The World ◽  
New Structural Economics

The world economy needs a growth-lifting strategy, and infrastructure financing seems to hold the key. Based on the New Structural Economics (Lin, 2010; 2012) we discuss the heterogeneity of capital focusing on the long-term versus short-term orientation (STO). Traditional neoliberalism assumes that capital is homogenous, complete capital account liberalization is “beneficial”.However, previous studies have found evidence of long-term orientation (LTO) in the culture of many Asian economies (Hofstede, 1991). In this exploratory paper, we suggest that the LTO can be considered a special endowment which, under certain circumstances, can be developed into a comparative advantage (CA) in patient capital. If these countries can turn their latent CA into arevealed CA in patient capital, and develop the ability to “package” profitable and non-profitable projects in meaningful ways, they would have a “revealed” competitive advantage in infrastructure financing. The ability to “package” public infrastructure and private services is one of the key institutional factors for success in overseas cooperation.

scholarly journals Metabolic plasticity can amplify ecosystem responses to global warming

2021 ◽  
Author(s):  
Rebecca Kordas ◽  
Samraat Pawar ◽  
Guy Woodward ◽  
Eoin O'Gorman
Keyword(s):  
Global Warming ◽  
Body Size ◽  
Predictive Models ◽  
Chronic Exposure ◽  
Ecosystem Respiration ◽  
Short Term ◽  
Ecosystem Responses ◽  
Metabolic Plasticity ◽  
Ecosystem Level

Abstract Organisms have the capacity to alter their physiological response to warming through acclimation or adaptation, but empirical evidence for this metabolic plasticity across species within food webs is lacking, and a generalisable framework does not exist for modelling its ecosystem-level consequences. Here we show that the ability of organisms to raise their metabolic rate following chronic exposure to warming decreases with increasing body size. Chronic exposure to higher temperatures also increases the sensitivity of organisms to short-term warming, irrespective of their body size. A mathematical model parameterised with these findings shows that metabolic plasticity could account for an additional 60% of ecosystem energy flux with just +2 °C of warming. This could explain why ecosystem respiration continues to rise in long-term warming experiments and highlights the need to embed metabolic plasticity in predictive models of global warming impacts on ecosystems.

scholarly journals Prospects for Vietnam’s Economy in 2013

2013 ◽  
Vol 215 ◽  
pp. 02-11
Author(s):  
NGÂN TRẦN HOÀNG
Keyword(s):  
Economic Growth ◽  
Growth Rate ◽  
World Economy ◽  
Inflation Rate ◽  
Economic Restructuring ◽  
Short Term ◽  
Economic Growth Model ◽  
The World ◽  
Global Growth

In 2012, Vietnam?s economy faced great challenges. The world economy experienced more difficulties and complicated upheavals. International trade fell drastically while global growth rate was lower than predicted target, which affected badly the Vietnamese economy because of its full integration into the world economy and large openness. In this context, principal targets set for 2013 are macroeconomic stability, lower inflation rate, higher growth rate, three strategic breakthroughs associated with restructuring of the economy, and a new economic growth model. This paper analyzes obstacles to Vietnam?s economic growth, and offers short-term solutions to bottlenecks and long-term ones to the economic restructuring.

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