981 resultados para Tariff on fishes
Resumo:
Concerns about the impacts of ocean acidification on marine life have mostly focused on how reduced carbonate saturation affects calcifying organisms. Here, we show that levels of CO2-induced acidification that may be attained by 2100 could also have significant effects on marine organisms by reducing their aerobic capacity. The effects of temperature and acidification on oxygen consumption were tested in 2 species of coral reef fishes, Ostorhinchus doederleini and O. cyanosoma, from the Great Barrier Reef, Australia. The capacity for aerobic activity (aerobic scope) declined at temperatures above the summer average (29°C) and in CO2-acidified water (pH 7.8 and ~1000 ppm CO2) compared to control water (pH 8.15). Aerobic scope declined by 36 and 32% for O. doederleini and O. cyanosoma at temperatures between 29 to 32°C, whereas it declined by 33 and 47% for O. doederleini and O. cyanosoma in acidified water compared to control water. Thus, the declines in aerobic scope in acidified water were similar to those caused by a 3°C increase in water temperature. Minimum aerobic scope values of ~200 mg O2 kg-1 h-1 were attained for both species in acidified water at 32°C, compared with over 600 mg O2 kg-1 h-1 in control water at 29°C. Mortality rate increased sharply at 33°C, indicating that this temperature is close to the lethal thermal limit for both species. Acidification further increased the mortality rate of O. doederleini, but not of O. cyanosoma. These results show that coral reef fishes are sensitive to both higher temperatures and increased levels of dissolved CO2, and that the aerobic performance of some reef fishes could be significantly reduced if climate change continues unabated.
Resumo:
Behaviour and sensory performance of marine fishes are impaired at CO2 levels projected to occur in the ocean in the next 50-100 years, and there is limited potential for within-generation acclimation to elevated CO2. However, whether fish behaviour can acclimate or adapt to elevated CO2 over multiple generations remains unanswered. We tested for transgenerational acclimation of reef fish olfactory preferences and behavioural lateralization at moderate (656 µatm) and high (912 µatm) end-of-century CO2 projections. Juvenile spiny damselfish, Acanthochromis polyacanthus, from control parents (446 µatm) exhibited an innate avoidance to chemical alarm cue (CAC) when reared in control conditions. In contrast, juveniles lost their innate avoidance of CAC and even became strongly attracted to CAC when reared at elevated CO2 levels. Juveniles from parents maintained at mid-CO2 and high-CO2 levels also lost their innate avoidance of CAC when reared in elevated CO2, demonstrating no capacity for transgenerational acclimation of olfactory responses. Behavioural lateralization was also disrupted for juveniles reared under elevated CO2, regardless of parental conditioning. Our results show minimal potential for transgenerational acclimation in this fish, suggesting that genetic adaptation will be necessary to overcome the effects of ocean acidification on behaviour.
Resumo:
Reproduction in many organisms can be disrupted by changes to the physical environment, such as those predicted to occur during climate change. Marine organisms face the dual climate change threats of increasing temperature and ocean acidification, yet no studies have examined the potential interactive effects of these stressors on reproduction in marine fishes. We used a long-term experiment to test the interactive effects of increased temperature and CO2 on the reproductive performance of the anemonefish, Amphiprion melanopus. Adult breeding pairs were kept for 10 months at three temperatures, 28.5°C (+0.0°C), 30.0°C (+1.5°C) and 31.5°C (+3.0°C), cross-factored with 3 CO2 levels, a current day control (417 µatm) and moderate (644 µatm) and high (1134 µatm) treatments consistent with the range of CO2 projections for the year 2100 under RCP8.5. We recorded each egg clutch produced during the breeding season, the number of eggs laid per clutch, average egg size, fertilization success, survival to hatching, hatchling length and yolk provisioning. Adult body condition, hepatosomatic index, gonadosomatic index, and plasma 17beta-estradiol concentrations were measured at the end of the breeding season to determine the effect of prolonged exposure to increased temperature and elevated CO2 on adults, and to examine potential physiological mechanisms for changes in reproduction. Temperature had by far the stronger influence on reproduction, with clear declines in reproduction occurring in the +1.5°C treatment and ceasing altogether in the +3.0°C treatment. In contrast, CO2 had a minimal effect on the majority of reproductive traits measured, but caused a decline in offspring quality in combination with elevated temperature. We detected no significant effect of temperature or CO2 on adult body condition or hepatosomatic index. Elevated temperature had a significant negative effect on plasma 17beta-estradiol concentrations, suggesting that declines in reproduction with increasing temperature were due to the thermal sensitivity of reproductive hormones rather than a reduction in energy available for reproduction. Our results show that elevated temperature exerts a stronger influence than high CO2 on reproduction in A. melanopus. Understanding how these two environmental variables interact to affect the reproductive performance of marine organisms will be important for predicting the future impacts of climate change.
Resumo:
We examine the potential impact of TTIP through trade-cost reductions, applying a mix of econometric and computational methods to develop estimates of the benefits (and costs) for the EU, United States, and third countries. Econometric results point to an approximate 80% growth in bilateral trade with an ambitious trade agreement. However, at the same time, computable general equilibrium (CGE) estimates highlight distributional impacts across countries and factors not evident from econometrics alone. Translated through our CGE framework, while bilateral trade increases roughly 80%, there is a fall of about 2.5% in trade with the rest of the world in our central case. The estimated gains in annual consumption range between 1% and 2.25% for the United States and EU, respectively. A purely discriminatory agreement would harm most countries outside the agreement, while the direction of third-country effects hinges critically on whether NTB reductions end up being discriminatory or not. Within the United States and EU, while labour gains across skill categories, the impact on farmers is mixed.
Resumo:
Effects of severe hypercapnia have been extensively studied in marine fishes, while knowledge on the impacts of moderately elevated CO2 levels and their combination with warming is scarce. Here we investigate ion regulation mechanisms and energy budget in gills from Atlantic cod acclimated long-term to elevated PCO2 levels (2500 µatm) and temperature (18 °C). Isolated perfused gill preparations established to determine gill thermal plasticity during acute exposures (10-22 °C) and in vivo costs of Na+/K+-ATPase activity, protein and RNA synthesis. Maximum enzyme capacities of F1Fo-ATPase, H+-ATPase and Na+/K+-ATPase were measured in vitro in crude gill homogenates. After whole animal acclimation to elevated PCO2 and/or warming, branchial oxygen consumption responded more strongly to acute temperature change. The fractions of gill respiration allocated to protein and RNA synthesis remained unchanged. In gills of fish CO2-exposed at both temperatures, energy turnover associated with Na+/K+-ATPase activity was reduced by 30% below rates of control fish. This contrasted in vitro capacities of Na+/K+-ATPase, which remained unchanged under elevated CO2 at 10 °C, and earlier studies which had found a strong upregulation under severe hypercapnia. F1Fo-ATPase capacities increased in hypercapnic gills at both temperatures, whereas Na+/K+ATPase and H+-ATPase capacities only increased in response to elevated CO2 and warming indicating the absence of thermal compensation under CO2. We conclude that in vivo ion regulatory energy demand is lowered under moderately elevated CO2 levels despite the stronger thermal response of total gill respiration and the upregulation of F1Fo-ATPase. This effect is maintained at elevated temperature.
Resumo:
In this paper, we examined back-and-forth international transactions through tariff reduction by estimating modified gravity equations for finished goods and intermediate goods separately. Our main findings are as follows. Exports of finished machinery products are negatively associated with not only the importer's tariff rates on finished machinery products but also the exporter's tariff rates on machinery parts. Similarly, exports of machinery parts are negatively associated with not only the importer's tariff rates on machinery parts but also the exporter's tariff rates on finished machinery products. These results imply that tariff reduction in only one production process in an industry has the potential to drastically change the magnitude of trade in the whole industry.
Resumo:
In this paper, we empirically investigate the effect of diagonal cumulation on free trade agreement (FTA) utilization by exploring Thai exports to Japan under two kinds of FTA schemes. While the one scheme adopts bilateral cumulation, the other scheme does diagonal cumulation. Comparing trade under these two kinds of FTAs, we can examine the effect of diagonal cumulation without relying on not only the variation in cumulation rules across country pairs but also the variation across years. In short, our estimates do not suffer from biases from time-variant elements and country pair-specific elements. As a result, our estimates show around 4% trade creation effect of diagonal cumulation, which is much smaller than the estimates in the previous studies (around 15%).
Resumo:
The rules governing the trade of goods in global markets have shifted toward non-tariff measures related to environmental and chemical safety. Unlike traditional environmental/safety requirements, the scope of modern regulations covers products’ environmental performance and chemical safety. To comply with these modern regulations, production practices along the entire supply chain must be realigned to manage certain chemical substances incorporated into the final product. This paper examines the implications of product-related environmental and chemical safety regulations on different firms operating in Thailand.
Resumo:
This paper examines empirically the impacts of sharing rules of origin (RoOs) with other ASEAN+1 free trade agreements (FTAs) on ASEAN-Korea FTA/ASEAN-China FTA utilization in Thai exports in 2011. Our careful empirical analysis suggests that the harmonization of RoOs across FTAs play some role in reducing the costs yielded through the spaghetti bowl phenomenon. In particular, the harmonization to "change-in-tariff classification (CTC) or real value-added content (RVC)" will play a relatively positive role in not seriously discouraging firms’ use of multiple FTA schemes. On the other hand, the harmonization to CTC or CTC&RVC hinders firms from using those schemes.
Resumo:
This paper empirically investigates how far free trade agreements (FTAs) successfully lower tariff rates and non-tariff barriers (NTBs) for manufacturing industries by employing the bilateral tariff and NTB data in a time series for countries around the world. We find that FTAs under GATT Article XXIV and the Enabling Clause contribute to reducing tariff rates by 2.1% points and 1.5% points, respectively. In the case of NTBs, their respective impacts are 6.6% points and 5.7% points. Membership in the World Trade Organization (WTO) does not contribute greatly to reducing tariff rates but does play a significant role in reducing NTBs. These results provide important implications for the literature on numerical assessments of FTAs.
Resumo:
International production fragmentation has been a global trend for decades, becoming especially important in Asia where the manufacturing process is fragmented into stages and dispersed around the region. This paper examines the effects of input and output tariff reductions on labor demand elasticities at the firm level. For this purpose, we consider a simple heterogenous firm model in which firms are allowed to export their products and to use imported intermediate inputs. The model predicts that only productive firms can use imported intermediate inputs (outsourcing) and tend to have larger constant-output labor demand elasticities. Input tariff reductions would lower the factor shares of labor for these productive firms and raise conditional labor demand elasticities further. We test these empirical predictions, constructing Chinese firm-level panel data over the 2000--2006 period. Controlling for potential tariff endogeneity by instruments, our empirical studies generally support these predictions.
Resumo:
This paper uses a GVC (Global Value Chain)-based CGE model to assess the impact of TTIP between the U.S. and the EU on their main trading partners who are mainly engaged at the low end in the division system of global value chains, such as BRICS countries. The simulation results indicate that in general the TTIP would positively impact global trade and economies due to the reduction of both tariff and non-tariff barriers. With great increases in the US–EU bilateral trade, significant economic gains for the U.S. and the EU can be expected. For most BRICS countries, the aggregate exports and GDP suffer small negative impacts from the TTIP, except Brazil, but the inter-country trade within BRICS economies increases due to the substitution effect between the US–EU trade and the imports from BRICS countries when the TTIP commences.
Resumo:
This paper investigates how exchange rates affect the utilization of a free trade agreement (FTA) scheme in trading. Changes in exchange rates affect FTA utilization by two ways. The first way is by changing the excess profits gained by utilizing the FTA scheme, and the second way is by promoting the compliance of rules of origin. Our theoretical models predict that the depreciation of exporters' currency against that of importers enhances the likelihood of FTA utilization through those two channels. Furthermore, our empirical analysis, which is based on rich tariff-line-level data on the utilization of FTA schemes in Korea's imports from ASEAN countries, supports the theoretical prediction. We also show that the effects are smaller for more differentiated products.
Resumo:
This paper explores the potential usefulness of an AGE model with the Melitz-type trade specification to assess economic effects of technical regulations, taking the case of the EU ELV/RoHS directives as an example. Simulation experiments reveal that: (1) raising the fixed exporting cost to make sales in the EU market brings results that exports of the targeted commodities (motor vehicles and parts for ELV and electronic equipment for RoHS) to the EU from outside regions/countries expand while the domestic trade in the EU shrinks when the importer's preference for variety (PfV) is not strong; (2) if the PfV is not strong, policy changes that may bring reduction in the number of firms enable survived producers with high productivity to expand production to be large-scale mass producers fully enjoying the fruit of economies of scale; and (3) When the strength of the importer's PfV is changed from zero to unity, there is the value that totally changes simulation results and their interpretations.
Resumo:
This paper reports on the IES-UPM experience from 2006 to 2010 in the field of the characterization of PV arrays of commercial large PV plants installed in Spain within the framework of the profitable economic scenarios associated to feed-in tariff laws. This experience has extended to 200 MW and has provided valuable lessons to minimize uncertainty, which plays a key role in quality assurance procedures. The paper deals not only with classic I–V measurements but also with watt-metering-based procedures. Particular attention is paid to the selection of irradiance and cell temperature sensors