On the Nexus of SO<Subscript>2</Subscript> and CO<Subscript>2</Subscript> emissions in China: the ancillary benefits of CO<Subscript>2</Subscript> emission reductions

This paper examines the issue of ancillary benefits by linking sulfur dioxide (SO₂) emission to CO₂ emission using a panel of 29 Chinese provinces over the period 1995–2007. In the presence of non-stationarity and cointegrating properties of these two data series, this paper applies the panel cointegration techniques to examine both the long-run and short-run elasticities of SO₂ with respect to CO₂. The major findings are that: (1) there exhibits a stable long-run equilibrium relationship between the SO₂ and CO₂ emission with the long-run elasticity being 2.15; (2) there exists a short-run relationship between these two emissions with the short-run elasticity being 0.04. In addition, following an exogenous shock that causes a deviation from the long-run equilibrium, it would take approximately 15 years for SO₂ emission to revert toward the long-run equilibrium path with an average annual convergence rate of 6.5%; (3) the derived ancillary benefits that is generated from one metric ton of CO₂ emission reduction, are 11.77 Yuan (approximately US1.7) in the short run and 196.16 Yuan (US 1.7) in the short run and 196.16 Yuan (US 30) in the long run. These findings are not only crucial from the econometric modeling perspective, but also have important policy implications.     

Impacts of economic growth and urbanization on CO<Subscript>2</Subscript> emissions: regional differences in China based on panel estimation

This study analyzed the impact of urbanization and the level of economic development on CO₂ emissions using the STIRPAT model and provincial panel data for China. This study classified the 29 provinces of China into three groups (eastern, central, and western regions) and examined regional differences in the environmental impacts of urbanization and economic development levels. The results demonstrated that there was an inverted U-shaped relationship between urbanization and CO₂ emissions in the central and western regions of China. However, we did not confirm the environmental Kuznets curve relationship between urbanization and CO₂ emissions in eastern China, where CO₂ emissions increase monotonically with urbanization. This study showed that the impacts of urbanization differ considerably. There was a U-shaped relationship between economic growth and CO₂ emissions. However, the point of inflexion was very low, which indicates that economic growth will promote CO₂ emissions in China. The share of the industry output value had a marginal incremental effect on CO₂ emissions. There was a decreasing effect of population scale on CO₂ emissions. Energy efficiency is the main factor that restrains CO₂ emissions, and the effect was higher in regions with low energy efficiency.     

Interpreting soil CO<Subscript>2</Subscript> transport and production in oasis cotton field,central Asia

In order to explore soil profile CO₂ transport and production, values of vertical soil profile CO₂ concentration, moisture and temperature were measured continuously during whole cotton growing season in oasis cotton field of Aksu National Experimental Station of Oasis Farmland Ecosystem, central Asia. Simultaneously, soil CO₂ efflux was measured by chamber system to assess the deducing result by Fick’s first law. In our experiment, soil CO₂ effluxes were determined by two related intimately methods. Soil CO₂ releasing at 0–20 cm depth was calculated by gas transport equation and was found to be closely related to soil CO₂ efflux. However, mean values of soil CO₂ production at 0–20 cm depth were less than those of soil CO₂ efflux during the whole cotton growing season. Moreover, there were some negative values of CO₂ production at 0–20 cm depth found during the experimental period.     

Carbon and energy taxation for CO<Subscript>2</Subscript> mitigation: a CGE model of the Malaysia

Malaysia has made a pledge to reduce voluntarily her carbon dioxide-equivalent (CO₂-e) gas emission’s intensity of gross domestic product by up to 40 % based on 2005 levels by 2020. The country is considering implementing economic instruments, among others, to assist the achievement of emission reduction targets while contributing towards the nation’s energy security and sustainable development goals. This paper develops a computable general equilibrium model with explicit energy-emission linkages to appraise the economy-wide and welfare impacts of carbon and energy tax policies to reduce CO₂ emissions in Malaysia. Results indicate that the negative macroeconomic impacts of carbon and energy taxes are small relative to the quantum of emission reduction. A Hicksian welfare criterion is utilized to determine the impact of revenue natural shifts in carbon and energy taxes. Revenue neutrality assumptions show that carbon taxation is the best choice when it can provide a double dividend if the generated revenue is used for the purpose of consumption subsidy on household purchases. The notion of the double dividend is confirmed when the change in the consumption structure will result in a welfare improvement, while CO₂ emission is decreased effectively. The study also found that carbon tax policy results in greater emission reductions relative to energy taxes, while the use of renewable energy will increase more substantially.     

Tourism and CO<Subscript>2</Subscript> emissions nexus in Southeast Asia: new evidence from panel estimation

The past decade has seen the rapid development of the tourist industry in Southeast Asia. There is increasing concern that tourism is highly affecting CO₂ emissions, but the nature of the relationship is still unclear. The main target of this paper is to investigate the existence of a linear and/or nonlinear relationship between tourism and CO₂ emissions in the five most important countries located in Southeast Asia, using the panel cointegration and pooled mean group techniques. The results indicate that tourism and CO₂ emissions are cointegrated, implying that tourism affects CO₂ emissions in the long run. Our findings support the nonlinear relationship between tourism and emissions as well as economic activities and CO₂ emissions. Accordingly, an inverted U-shaped relationship exists between tourism and emissions confirming the existence of an Environmental Kuznets Curve in the Southeast Asian tourism industry. Furthermore, the empirical results show that economic activities and energy consumption greatly increase emissions.     

Developing sinks for CO<Subscript>2</Subscript> through forestation of temperate coastal barriers: an environmental business

Since the 1940s, some sectors of the sand dune barriers of Buenos Aires Province have been forested to fix the sand in the neighborhoods of resort villages. Man took advantage of the maritime climate and the shallow groundwater to introduce pine forests. Today, these forests reach more than 20 m in height and have developed soils of more than 0.05 m in thickness on former arid sands. Field data were referred to Landsat (TM) composite and Normalized Difference of Vegetation Index, NDVI, images to calculate forest density and covered area. Considering published tables of wood density for each species, the amount of total carbon storage was estimated on 318 t C ha^-1 (Mg=10⁶ g) in biomass and 86 t C ha^-1 in soils. The three areas analyzed at Miramar, Necochea and Claromecó have captured 658,868 t of carbon in the last 50 years. It is estimated that 150,000,000 t C could be sequestered within temperate dune barriers of Argentina, Uruguay and Brazil. Besides this ecological point of view, there is an important socio-economic factor that cannot be excluded.Presented at and revised subsequent to the 4th LOICZ Open Science Meeting, Bahía Blanca, Argentina. October 1999.     

Urban sprawl,public transport,and increasing CO<Subscript>2</Subscript> emissions: the case of Metro Manila,Philippines

Current international discussions on the increasingly critical levels of carbon emissions from the transportation sector commonly attribute the causality chain to urban sprawl growth–private car use–carbon emission. An often assumed development context of this causality chain is that common of developed country urbanization. However, in the particular context of developing country urbanization, urban sprawl and associated workplace–home distanciation may lead to more intensive use by the urban workforce of public mass transportation system, instead of higher dependence on private vehicle travel. Thus, the source of the rise in carbon emission may actually be the public transportation system. Utilizing mixed methods, combining quantitative (origin–destination matrices) and qualitative data gathering and analysis, the authors present a case study in Metro Manila which has been experiencing sprawl and increasing costs and unaffordability of land and housing in the workforce’s vicinity of employment. This, in turn, causes greater distances of daily travel between home and workplace using public transportation system. When the latter is characterized by fuel-inefficient small vehicles with second-hand engines, higher carbon emission results. We argue that the convergence of multiple interacting factors such as urban sprawl, lack of affordability of housing near the centres of employment, high dependence of commuters on public transports, longer distance travel by commuters, and low fuel efficiency of the public utility vehicles primarily causes the increase in CO₂ emission from the transport sector. Implications of this case to policy scoping of immediate and long-term state responses for carbon emission mitigation in transportation sector are discussed.     

Soil respiration in model plantations under conditions of elevated CO<Subscript>2</Subscript> in the atmosphere (Hokkaido Island,Japan)

The influence of long-term exposure of model plantations at elevated atmospheric CO₂ (550 ppm) on soil respiration under natural conditions has been studied using an automated Free-Air CO₂ Enrichment (FACE) system at the Hokkaido University, Japan. In the course of the experiment, an attempt has been made to simulate the effect of forthcoming climate change on the process of CO₂ emission from different soil types.     

Traditional management and conservation of shea trees (<Emphasis Type=Italic>Vitellaria paradoxa</Emphasis> subspecies <Emphasis Type=Italic>nilotica</Emphasis>) in Uganda

Traditional practices are universally recognised as a basis for conservation of biodiversity. However, such practices are often not included in natural resource conservation policies. This study assessed local conservation practices of shea trees (Vitellaria paradoxa) within different farming systems in Uganda and developed conservation guidelines for the species. The assessment involved 300 respondents, 15 focus groups and 41 key informants. Content analysis was used to identify the most important management and conservation practices. Local uses were categorised on the basis of shea tree products while differences in conservation practices were analysed using the Friedman test. The results show that eight shea tree products are used for 36 different purposes. Respondents’ age significantly influenced their knowledge about the shea tree. Traditional conservation practices include on-farm retention during cultivation and the use of folklore (mainly taboos), customs and rituals. Traditional management practices include weeding, bush burning, pollarding and pruning. Based on the current management and traditional conservation practices, a framework for the conservation of shea trees is proposed for integration into conservation policy decisions.     

Long-term dynamics of radioactive <Superscript>90</Superscript>Sr and <Superscript>137</Superscript>Cs contamination of small mammals in the Chernobyl zone

Between 1986 and 1994, a decrease in nonalimentary ⁹⁰Sr and ¹³⁷Cs intake and changes in the accessibility of radionuclides in the soil-plant link of their cycle resulted in a 10-to 100-fold decrease in their specific activity (SA) in the bodies of small mammals inhabiting the Chernobyl zone, and a similar decrease was observed in the radionuclide transition factor (TF) in the soil-animal chain. Between 1995 and 2005, no consistent increase or decrease in SA or TF could be revealed against the background of a combined effect of different physicochemical and ecological factors. It is suggested that subsequent changes in the level of radioactive contamination of small mammals will generally reflect only the dynamics of physical ⁹⁰Sr and ¹³⁷Cs decay, but, nevertheless, seasonal and local variations in this level will be significant.     

Halotolerant bacteria of the genus <Emphasis Type="Italic">Arthrobacter</Emphasis> degrading polycyclic aromatic hydrocarbons

Eight strains of bacteria capable of degrading polycyclic aromatic hydrocarbons have been isolated from soils and bottom sediments sampled in the region of Verkhnekamskoe potash deposit (Berezniki, Perm krai) and classified with the genus Arthrobacter on the basis of phylogenetic analysis (16S rRNA genes) and morphological and chemotaxonomic characters. According to the results of 16S rDNA sequence alignment, strains B905, SMB11, SMB145, SF27, and DF14 show the highest sequence homology to the type strain of A. crystallopoietes (99.7%), and strain SN17, to the type strain of A. arilaitensis (99.8%). The isolated strains are capable of growing on naphthalene and phenanthrene (as the sole sources of carbon and energy) in the presence of 60 mg/l NaCl. Their cells contain large plasmids ranging in size from 85 to 130 kb. Plasmid elimination from Arthrobacter sp. SF27 has proved to result in the loss of capacity for growing on naphthalene and phenanthrene, suggesting a plasmid localization of genes responsible for degradation of these compounds.     

Influence of silts on the growth,reproduction and chlorophyll fluorescence of <Emphasis Type=Italic>Potamogeton crispus</Emphasis> in turbid water

Turions of Potamogeton crispus were planted in several turbid waters. Some parameters of growth, reproduction and chlorophyll fluorescence were measured. The results were as follows: (1) Sprouting rates in all groups reached to 100.0% on the 17^th day. (2) The parameters of the growth (stem and leaf) and chlorophyll fluorescence (Φ_PSII, qP and qN) in 120 and 150NTU waters were inhibited heavily 60 days later, and their survival time was only 140 days. However, the plants in 30 to 90NTU waters could grow near water surface, their survival time was about 190 days. (3) After 150 days, the saturating irradiance intensity and rETR_max of the leaves in 30 to 90NTU waters markedly decreased with an increase in the amount of attached silts, and the number and fresh mass of turions (propagula) in 60 and 90NTU waters were significantly lower than the control. In summary, P. crispus in 0.7-metre-deep turbid water with suspended silts (not more than 90NTU) could sprout and grow normally, and produce the turions.     

Interspecific interactions of amphipods <Emphasis Type="Italic">Gammarus lacustris</Emphasis> and <Emphasis Type="Italic">Gmelinoides fasciatus</Emphasis>

Experimental studies of interactions between two amphipod species (Gmelinoides fasciatus and Gammarus lacustris) showed that predation is the basic mechanism accounting for their mutual exclusion in nature. Mortality from predation among similar-sized specimens of both species at an equal abundance ratio was similar (24–25% in G. lacustris and 27–30% in G. fasciatus). The displacement of G. lacustris by G. fasciatus was observed when the latter was dominant. Adult G. fasciatus and G. lacustris successfully preyed on juveniles of their competitors and did not differ significantly in daily food consumption as a percentage of body weight: 6–24% at a fresh body weight of 18–24 mg in both species. The potential for rapid population growth under new conditions contributed to the success of the invasive Baikal species G. fasciatus in displacing G. lacustris from many water bodies of Russia.     

Combined influence of food level and inoculation density on competition between <Emphasis Type="Italic">Anuraeopsis fissa</Emphasis> and <Emphasis Type="Italic">Brachionus patulus</Emphasis> or <Emphasis Type="Italic">Brachionus macracanthus</Emphasis> (Rotifera: Brachionidae)

We tested separately the effect of two taxonomically related rotifers (B. patulus and B. macracanthus) on the population dynamics of another species (A. fissa) at low (0.5 ×10 ⁶) and high food levels (1.5 × 10⁶ cells/ml of Chlorella vulgaris) using different inoculation densities (0–100%). We also quantified the impact of A. fissa on the two brachionid species. Regardless of the presence of the competing species, an increase in the availability of food led to increase in the abundances of the three rotifers. The population growth of B. patulus, B. macracanthus, or A. fissa was affected negatively when cultured together with another species. An increase in the initial density of any one of the competing species became advantageous to maintain a certain population size. At a low algal food level, B. patulus was able to suppress A. fissa more strongly than B. macracanthus. On the other hand, at a high food level, B. macracanthus suppressed the population of A. fissa more strongly than B. patulus. Peak population densities for A. fissa varied from about 150 to 1000 ind./ml, depending on food density and the presence of competitors. The rate of population increase (r) of A. fissa, B. patulus, and B. macracanthus increased with an increase in food availability but decreased with increasing initial density of the competitor. Both Brachionus spp. experienced negative growth rates in the presence of A. fissa, especially at a high initial density of the latter. Published in Russian in Ekologiya, 2007, Vol. 38, No. 5, pp. 381–390. The article was submitted by the authors in English.     

Assessment of the reproductive capacity of <Emphasis Type="Italic">Pinus sylvestris</Emphasis> trees growing under conditions of chronic exposure to radionuclides of uranium and thorium series

The reproductive capacity of Scots pine (Pinus sylvestris L.) has been estimated in trees from the population growing in an area used to store tailings from uranium ore processing and radium production. Under such conditions, 12- to 15-year-old trees produce seeds of a quality inferior to that in areas with a normal background radiation level. As the weighted absorbed dose rate (at a weighting coefficient of 5) for generative organs increases from 0.002 ± 0.0003 to 0.344 ± 0.059 mGy/day, a proportional increase is observed in the proportion of empty seeds and the frequency of cytogenetic disturbances in the root meristem of seedlings, while the survival rate of seedlings decreases. The minimum absorbed dose rate leading to these changes in the pine population is 0.027 mGy/day, i.e., 12 times as high as the control value.     

Photosynthetic and biochemical characteristics of invasive species (<Emphasis Type="Italic">Ambrosia artemisiifolia L., Ambrosia trifida L.</Emphasis> and <Emphasis Type="Italic">Iva xanthifolia Nutt.</Emphasis>) depending on soil humidity and phenological phase

Environmental factors like temperature and soil humidity are recognized as influencing factors on photosynthetic response and organic productivity, distribution and biochemical characteristics of plants. Here we present measurements of gas exchange parameters, water-use efficiency (WUE) and nitrogen-use efficiency (NUE) of field-grown invasive species Ambrosia artemisiifolia L., Ambrosia trifida L. and Iva xanthifolia Nutt., in order to define their potentials as colonizers. Biogenic volatile organic compounds (BVOC) in leaves and flowers depending on soil humidity were also investigated.