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On the Non-Compliance in the North Sea Cod Stock  [PDF]
Sebastian Villasante,David Rodríguez-González,Manel Antelo
Sustainability , 2013, DOI: 10.3390/su5051974
Abstract: This paper estimates the economic value of the North Sea cod ( Gadus morhua) stock under recent catch and several recovery scenarios. The research presents results on: a) what the value of catches and biomass would have been if the EU fishing fleet had followed the International Council for the Exploration of the Sea scientific recommendations (SRs) and Total Allowable Catches (TACs) in the 1986–2010 period; and b) what the value of catches and biomass will be for the 2010–2022 period if the fleet follows the current Common Fisheries Policy Reform (CFPR). Results show that the actual economic value of the stock for the 1986–2010 period has been US$7 billion, which is substantially lower than what would have been predicted had the industry followed the SRs (US$20.7 billion) or approved TACs (US$19.5 billion). Similarly, if catches do not follow the SRs or the approved TACs for the 2010–2022 period the estimated economic value of the stock is predicted to be lower than if they had done so. Further, the losses of non-compliance increase even when a scenario of 50% reduction of discards under the new CFPR is considered. We also show that the status of the stock is strongly dependent on the trade-offs generated by both the non-compliance of scientific recommendations and by the short-term economic incentives of the fishing industry. With most fishery resources fully exploited or overexploited in Europe, opportunities for development lie primarily in restoring depleted stocks and catching fish more efficiently, as is the case of the North Sea cod stock.
Volatility Transmission from Mature Global Stock Markets to Middle East and North African Stock Markets  [cached]
Akash Dania,John E. Spillan
Accounting and Finance Research , 2012, DOI: 10.5430/afr.v2n1p19
Abstract: The objective of this paper is to model the dynamics of volatility transmission from mature global stock markets of France, Germany, UK and the US to MENA (Middle East and North African) markets of Bahrain, Egypt, Jordan, Kuwait, Lebanon, Morocco, Oman, Qatar, Tunisia, and the United Arab Emirates. GARCH, TGARCH models of returns are estimated to determine evidence of volatility spillover from global mature markets to emerging or less mature markets of MENA region. We find evidence of different level of volatility spillover and leverage effect. This varying response to global stock market shocks reveals that MENA stock markets are not fully integrated with global economy.
Snow as relevant factor in determining carbon stock in the soil
Tonon G
Forest@ , 2006,
Abstract: Based on recent experimental evidence, a comment is made on the importance of snow depth in controlliing soil temperature and decomposition rate of soil organic matter, with special reference to mountain ecosystems.
The Variations in Calcaneal Articular Facets In North Indian Population and its Clinical Implication
Seema,Maninder Singh,Anupama Mahajan,Deepinder Kaur Gandhi
Global Journal of Medicine and Public Health , 2012,
Abstract: Aims and Objectives- To know the most common type of calcanei in North Indian population and itsclinical importance. There are three articular facets on superior surface of calcaneus- anterior, middle andposterior. Three types of calcanei are noted according to number and arrangement of the articular facets-type A, B and C. Methodology - The present studywas done on 300 dry adult human calcanei of unknownsex taken from Department of Anatomy Sri Guru Ram Das Institute of Medical Sciences and ResearchVallah (Amritsar). Results- In our study Type B was found as the most common type. Type A is the nextmost common. Interpretation- The talocalcaneal joint is important in arthritis and coalition, flat foot, valgus deformity, congenital anomalies and intra articular fractures.
Loss of Persistence of the North Atlantic Oscillation and its Biological Implication  [PDF]
Joachim W. Dippner,Caroline M?ller
Frontiers in Ecology and Evolution , 2014, DOI: 10.3389/fevo.2014.00057
Abstract: Winter sea-level pressure fields in the northern hemisphere were analysed with respect to regimes and regime shifts (RS). Classification of the North Atlantic Oscillation (NAO) patterns resulted in the identification of two longer lasting climate regimes: a persistent NAO? period from 1976 to 1988 followed by a persistent NAO+ period from 1989 to 2000. A further persistent NAO? period from 1956 to 1966 cannot be related to climate regime shifts. After 2000, the NAO lost its persistence and the autocorrelation disappeared, while the variance in the benthic data increased. The consequence was a decrease in potential predictability. The impact of the 1988/89 and 2000/2001 RS on the dominant species and taxonomic groups of benthic macrofauna as well as on benthic community structure was evaluated using an AMOEBA model, a quantitative method used in water management to represent the status of the ecosystem. The model confirmed the effects of the smooth RS in 1988/1989 and the abrupt RS in 2000/2001 on the macrofauna communities provided by earlier data analyses.
FIELD SOIL-WATER CHARACTERISTICS AND ITS ENGINEERING IMPLICATION
野外土-水特征及其工程意义

Li A G,Yue Z Q,Tham L G,Lee C F,Law K T,
李爱国
,岳中琦,谭国焕,李焯芬,罗锦添

岩石力学与工程学报 , 2004,
Abstract: In order to study soil-water characteristics of unsaturated soil slope, moisture probe and tensiometers are installed simultaneously for the soils at depths of 1, 2, 3 and 4 m at the crest of a cut slope in Hong Kong. Based on the field monitored results of volumetric water content and matric suction, field soil-water characteristic curves for the soils at different depths at the crest are determined. Compared with the obvious hysteresis of laboratory soil-water characteristic curves,the field soil-water characteristic curve shows negligible hysteresis. The negligible hysteresis may be attributed to the non-equilibrium effect during the heavy rainfall or the different measurements of volumetric water contents and matric suctions in the field and laboratory. Furthermore,the engineering implication of the field soil-water characteristic curve is also discussed in this paper.
How accurately can soil organic carbon stocks and stock changes be quantified by soil inventories?
M. Schrumpf, E. D. Schulze, K. Kaiser,J. Schumacher
Biogeosciences (BG) & Discussions (BGD) , 2011,
Abstract: Precise determination of changes in organic carbon (OC) stocks is prerequisite to understand the role of soils in the global cycling of carbon and to verify changes in stocks due to management. A large dataset was collected to form base to repeated soil inventories at 12 CarboEurope sites under different climate and land-use, and with different soil types. Concentration of OC, bulk density (BD), and fine earth fraction were determined to 60 cm depth at 100 sampling points per site. We investigated (1) time needed to detect changes in soil OC, assuming future re-sampling of 100 cores; (2) the contribution of different sources of uncertainties to OC stocks; (3) the effect of OC stock calculation on mass rather than volume base for change detection; and (4) the potential use of pedotransfer functions (PTF) for estimating BD in repeated inventories. The period of time needed for soil OC stocks to change strongly enough to be detectable depends on the spatial variability of soil properties, the depth increment considered, and the rate of change. Cropland sites, having small spatial variability, had lower minimum detectable differences (MDD) with 100 sampling points (105 ± 28 gC m 2 for the upper 10 cm of the soil) than grassland and forest sites (206 ± 64 and 246 ± 64 gC m 2 for 0–10 cm, respectively). Expected general trends in soil OC indicate that changes could be detectable after 2–15 yr with 100 samples if changes occurred in the upper 10 cm of stone-poor soils. Error propagation analyses showed that in undisturbed soils with low stone contents, OC concentrations contributed most to OC stock variability while BD and fine earth fraction were more important in upper soil layers of croplands and in stone rich soils. Though the calculation of OC stocks based on equivalent soil masses slightly decreases the chance to detect changes with time at most sites except for the croplands, it is still recommended to account for changing bulk densities with time. Application of PTF for the estimation of bulk densities caused considerable underestimation of total variances of OC stocks if the error associated with the PTF was not accounted for, which rarely is done in soil inventories. Direct measurement of all relevant parameters approximately every 10 yr is recommended for repeated soil OC inventories.
How accurately can soil organic carbon stocks and stock changes be quantified by soil inventories?
M. Schrumpf,E. D. Schulze,K. Kaiser,J. Schumacher
Biogeosciences Discussions , 2011, DOI: 10.5194/bgd-8-723-2011
Abstract: Precise determination of changes in organic carbon (OC) stocks is prerequisite to understand the role of soils in the global cycling of carbon and to verify changes in stocks due to management. A large dataset was collected to form base to repeated soil inventories at 12 CarboEurope sites under different climate and land-use, and with different soil types. Concentration of OC, bulk density (BD), and fine earth fraction were determined to 60 cm depth at 100 sampling points per site. We investigated (1) time needed to detect changes in soil OC, assuming future re-sampling of 100 cores; (2) the contribution of different sources of uncertainties to OC stocks; (3) the effect of OC stock calculation on mass rather than volume base for change detection; and (4) the potential use of pedotransfer functions (PTF) for estimating BD in repeated inventories. The period of time needed for soil OC stocks to change strongly enough to be detectable depends on the spatial variability of soil properties, the depth increment considered, and the rate of change. Cropland sites, having small spatial variability, had lower minimum detectable differences (MDD) with 100 sampling points (105 ± 28 kg C m 2 for the upper 10 cm of the soil) than the grassland (206 ± 64 kg C m 2) and forest (246 ± 64 kg C m 2) sites. Expected general trends in soil OC indicate that changes could be detectable after 2–15 years with 100 samples if changes occurred in the upper 10 cm of stone-poor soils. Error propagation analyses showed that in undisturbed soils with low stone contents, OC concentrations contributed most to OC stock variability while BD and fine earth fraction were more important in upper soil layers of croplands and in stone rich soils. Though the calculation of OC stocks based on equivalent soil masses slightly decreases the chance to detect changes with time at most sites except for the croplands, it is still recommended to account for changing bulk densities with time. Application of PTF for the estimation of bulk densities caused considerable underestimation of total variances of OC stocks if the error associated with the PTF was not accounted for, which rarely is done in soil inventories. Direct measurement of all relevant parameters approximately every 10 years is recommended for repeated soil OC inventories.
Variability of Soil Physical Properties in a Clay-Loam Soil and Its Implication on Soil Management Practices  [PDF]
Samuel I. Haruna,Nsalambi V. Nkongolo
ISRN Soil Science , 2013, DOI: 10.1155/2013/418586
Abstract: We assessed the spatial variability of soil physical properties in a clay-loam soil cropped to corn and soybean. The study was conducted at Lincoln University in Jefferson City, Missouri. Soil samples were taken at four depths: 0–10?cm, 10–20, 20–40, and 40–60?cm and were oven dried at 105°C for 72 hours. Bulk density (BDY), volumetric (VWC) and gravimetric (GWC) water contents, volumetric air content (VAC), total pore space (TPS), air-filled (AFPS) and water-filled (WFPS) pore space, the relative gas diffusion coefficient (DIFF), and the pore tortuosity factor (TORT) were calculated. Results showed that, in comparison to depth 1, means for AFPS, Diff, TPS, and VAC decreased in Depth 2. Opposingly, BDY, Tort, VWC, and WFPS increased in depth 2. Semivariogram analysis showed that GWC, VWC, BDY, and TPS in depth 2 fitted to an exponential variogram model. The range of spatial variability ( ) for BDY, TPS, VAC, WFPS, AFPS, DIFF, and TORT was the same (25.77?m) in depths 1 and 4, suggesting that these soil properties can be sampled together at the same distance. The analysis also showed the presence of a strong (≤25%) to weak (>75%) spatial dependence for soil physical properties. 1. Introduction Characterizing the spatial variability and distribution of soil properties is important in predicting the rates of ecosystem processes with respect to natural and anthropogenic factors [1] and in understanding how ecosystems and their services work [2]. In agriculture, studies of the effects of land management on soil properties have shown that cultivation generally increases the potential for soil degradation due to the breakdown of soil aggregates and the reduction of soil cohesion, water content and nutrient holding capacity [3, 4]. Cultivation, especially when accompanied by tillage, has been reported to have significant effects on topsoil structure and thus the ability of soil to fulfill essential soil functions and services in relation to root growth, gas and water transport and organic matter turnover [5–7]. Soil properties vary considerably under different crops, tillage type and intensity, fertilizer types and application rates. Consequently, the physical properties of the soil are also affected by many factors that change vertically with depth, laterally across fields and temporally in response to climate and human activity [8]. Since this variability affects plant growth, nutrient dynamics, and other soil processes, knowledge of the spatial variability of soil physical properties is therefore necessary. To study the spatial distribution of soil
Simulation of the changes of soil organic carbon stock of cropland in China
中国农田土壤有机碳贮量变化预测

DENG Xiang-zheng,JIANG Qun-ou,LIN Ying-zhi,HAN Jian-zhi,
邓祥征
,姜群鸥,林英志,韩健智

地理研究 , 2010,
Abstract: In this paper,we estimate the nationwide soil organic carbon stock in China during the three time periods of 1988-2000,2000-2012 and 2012-2020 with CENTURY model and analyze soil organic carbon stock changes of cropland in the nine agro-ecological zones,with the support of DLS which provides future land use pattern data.In order to estimate the dynamics of soil organic carbon stock,the CENTURY model,in which a soil organic matter decomposition sub-model,a water budget sub-model,a grassland/crop sub-model,a ...
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