The influence of carbon emissions disclosure on company financial value in an emerging economy

Few studies have been conducted on the impact of carbon emissions disclosure on firms’ financial performance in emerging economies. Furthermore, comparison between accounting-based measures and market-based ones remains limited. This article examines the effect of carbon emissions reporting on the financial value of South African companies for the period 2010–2015. Using panel regression approaches, the findings show that, in most cases, carbon emission disclosure generates a positive relationship with ROA (an accounting-based indicator) but a negative association with MVA (a market-based indicator). The article concludes that accounting-based indicators offer more explanatory power for corporate greening initiatives.     

Identifying land suitable for agricultural land reform using GIS-MCDA in South Africa

Land reform is identified as a key tool in fostering development in South Africa. Twenty years after the advent of democracy in South Africa, the land question remains a critical issue for policy makers. Several frameworks have been put in place by the government to identify land that is strategically located for land reform. However, many of these frameworks are not well aligned and not objective in defining strategically located land for land reform and often lead to unsustainable land use management practices. This has hampered the government’s land reform initiative in promoting agricultural land reform and food security. Accordingly, there is a need to develop a decision support tool that facilitates the identification of strategically located land for land reform. This study proposes the use of geographic information systems (GIS) and multi-criteria decision analysis (MCDA) to develop a strategically located land index (SLLI) to identify land suitable for agricultural land reform. Participatory workshops and the group analytical hierarchy process were utilised to identify and weigh criteria used in computing the SLLI. The results indicate that land that is suitable for agricultural land reform is scarce, and there are also competing needs on the highly suitable land for agriculture. The study demonstrates that GIS and MCDA are invaluable tools in facilitating evidence-based decision-making for land reform and sustainable land use management practices. The SLLI is not the panacea to land identification; there is also need to appreciate the contested nature of land in South Africa.     

Population genetic structure of the milkfish,<Emphasis Type="Italic"> Chanos chanos</Emphasis>, based on PCR-RFLP analysis of the mitochondrial control region

The milkfish, Chanos chanos (Forsskål, 1775) is a pelagic, monotypic gonorhynchiform widely distributed in the tropical Indo-Pacific. This study evaluates temporal variability of milkfish samples from the Philippine archipelago, and spatial variability at two geographic scales based on restriction fragment length polymorphism (RFLP) analysis of a portion of the mitochondrial control region. High levels of genetic diversity characterize the milkfish control region (mean h=0.908, =1.59%), with 74 haplotypes detected among the 367 fish analyzed. For temporal analysis of Philippine samples, milkfish were collected over 2 years from three sites (inter-annual variation), and sampled twice within a year during different seasons at four sites (intra-annual variation). No significant temporal variability was detected between or within years. Significant spatial differentiation among the Philippine samples was observed (F_ST=0.006, P<0.05), with two northeastern samples, Claveria and Dingalan, found to be genetically distinct. However, an hierarchical analysis of molecular variance (AMOVA), where samples were grouped into four geographic regions, revealed very low levels of genetic partitioning, with less than 1% of the total variation attributed to between-region differences, and lack of genetic structure. Nonetheless, the existence of putative northeastern Philippine populations is not discounted. Strong genetic structure across broad geographical scales was revealed by AMOVA, with 11% of the molecular variance based on haplotype frequencies allocated between three distinct groups: Indian Ocean, west Pacific (Philippines) and north central Pacific (Hawaii) The broad-scale genetic structure points to limited gene flow among disjunct Indo-Pacific populations.Communicated by T. Ikeda, Hakodate     

Evidence for differential selection and potential adaptive evolution in the worker caste of an inquiline social parasite

Social parasites exploit the socially managed resources of social insect colonies in order to maximise their own fitness. The inquilines are among the most specialised social parasites, because they are dependent on being fully integrated into their host's colony throughout their lives. They are usually relatives of their host and so share ancestral characteristics (Emery's rule). Closely related inquiline-host combinations offer a rare opportunity to study trade-offs in natural selection. This is because ancestral adaptations to a free-living state (e.g. the production of a worker caste) become redundant and may be replaced by novel, parasitic traits as the inquiline becomes more specialised. The dynamics of such processes are, however, unknown as virtually all extant inquiline social parasites have completely lost their worker caste. An exception is Acromyrmex insinuator, an incipient permanent social parasite of the leaf-cutting ant Acromyrmex echinatior. In the present study, we document the size distribution of parasite and host workers and infer how selection has acted on A. insinuator to reduce, but not eliminate, its investment in a worker caste. We show that the antibiotic producing metapleural glands of these parasite workers are significantly smaller than in their host counterparts and we deduce that the metapleural gland size in the host represents the ancestral state. We further show experimentally that social parasite workers are more vulnerable to the general insect pathogenic fungus Metarhizium than are host workers. Our findings suggest that costly disease resistance mechanisms are likely to have been lost early in inquiline evolution, possibly because active selection for maintaining these traits became less when parasite workers had evolved the ability to exploit the collective immune system of their host societies.     

Contaminants in water: non-target UHPLC/MS analysis

Contamination of water resources is one of the major problems to be faced for environment preservation and sustainability. The monitoring of target compounds based on mass spectrometry and selected reaction monitoring mode is often insufficient to definitely assess the quality of surface water. Also potentially harmful non-target pollutants simultaneously present must be taken into account. Liquid chromatography coupled with tandem mass spectrometry is suitable to obtain complete information on water composition. Hybrid mass spectrometers such as triple quadrupole/linear ion trap, hybrid quadrupole/time-of-flight and linear ion trap/orbitrap analyzers should be used. Here, we review ultra-high performance liquid chromatography coupled with mass spectrometry methods developed for post-target and non-target screening analysis of water emerging contaminants, such as pesticides and their degradation products, pharmaceuticals and drug side-reaction products, surfactants and illicit drugs. The major points are the following: (1) the possibility of performing retrospective analysis only by high-resolution mass analyzer; (2) the compatibility of mass analyzer with ultra-high performance liquid chromatography; (3) the use of deconvolution software to detect unknowns; and (4) the limited availability of library database.     

A novel sex-specific and inducible monoterpene synthase activity associated with a pine bark beetle,the pine engraver,<Emphasis Type="Italic"> Ips pini</Emphasis>

Ecological interactions of conifers and coniferophagous bark beetles are determined in part by terpenoids (isoprenoids), which are major defense metabolites of conifer oleoresin. Curiously, similar compounds are important aggregation pheromones of conifer-attacking bark beetles. Terpene synthases are responsible for generating the enormous variety of terpenoid carbon skeletons found in nature. These catalysts convert short-chain prenyl diphosphates to a diverse assortment of hemiterpene, monoterpene, sesquiterpene, and diterpene natural products. While terpene synthases have frequently been characterized from plant and microbial sources, they have not yet been described in animals. Here we report the discovery of a monoterpene synthase activity in an insect, the pine engraver, Ips pini (Say) (Coleoptera: Scolytidae). Cell-free assays of I. pini revealed that geranyl diphosphate (GDP) is converted to the acyclic monoterpene myrcene in whole-body extracts from males, but not females. Furthermore, the monoterpene synthase activity in males can be induced by prior treatment with juvenile hormone III (JH III) or by feeding on phloem from the host trees, Jeffrey pine (Pinus jeffreyi Grev. &; Balf.) or red pine (Pinus resinosa Ait.). The sex-specificity and endocrine induction of this activity argue for its involvement in the biosynthesis of monoterpenoid pheromones mediated by enzymes from insect tissue. This discovery is the first example of a monoterpene synthase in the Metazoa and evokes exciting new questions about the origin, evolution, and occurrence of terpene synthases.     

Seasonal and depth related variation in the photosynthesis–irradiance response of<Emphasis Type="Italic"> Ecklonia radiata</Emphasis> (Phaeophyta,Laminariales) at West Island,South Australia

The photosynthesis–irradiance response of Ecklonia radiata (C. Agardh) J. Agardh, a common kelp in the temperate southern hemisphere, was investigated in situ throughout the year and across a depth profile at West Island, South Australia. Temperature and irradiance environment altered throughout the year, varying at 3 m between 14–20°C and 279–705 mol photons m^–2 s^–1. Photosynthetic capacity (P_m) varied throughout the year between 177–278 mol O₂ g^–1 dry wt h^–1 at 3 m and 133–348 mol O₂ g^–1 dry wt h^–1 at 10 m. The irradiance required for sub-saturation of photosynthesis (E_k) varied between 97–152 and 81–142 mol photons m^–2 s^–1 for 3 m and 10 m respectively, and the respiration rate varied between 15–36 and 13–20 mol O₂ g^–1 dry wt h^–1 for 3 m and 10 m. A clear seasonal change in photokinetic parameters was detected and provided strong evidence for a seasonal acclimation response. During winter an increase in the efficiency of light utilisation at low irradiance () was accompanied by a decrease in both E_k and that required for photosynthetic compensation. P_m also increased during the winter and autumn months and respiratory requirements decreased. These changes enable E. radiata to display an optimal photosynthetic performance throughout the year despite significant changes in the surrounding environment.Communicated by P.W. Sammarco, Chauvin     

Strategies of maintaining the natural purification potential of rivers and lakes

Surface waters have a great impact on ecology and life of man. Because of their current use and exploitation, chemical and biological pollution, as well as physical changes of rivers and lakes are common. Natural self-purification potential helps to compensate harms to a certain degree. Proposals are given to detect restrictions of the purification potential in time as well as to support and to enhance the natural purification potential.     

Environmental photochemical fate of pesticides ametryn and imidacloprid in surface water (Paranapanema River,São Paulo,Brazil)

In addition to direct photolysis studies, in this work the second-order reaction rate constants of pesticides imidacloprid (IMD) and ametryn (AMT) with hydroxyl radicals (HO^●), singlet oxygen (¹O₂), and triplet excited states of chromophoric dissolved organic matter (³CDOM^*) were determined by kinetic competition under sunlight. IMD and AMT exhibited low photolysis quantum yields: (1.23?±?0.07)?×?10^–2 and (7.99?±?1.61)?×?10^–3 mol Einstein^?1, respectively. In contrast, reactions with HO^● radicals and ³CDOM* dominate their degradation, with ¹O₂ exhibiting rates three to five orders of magnitude lower. The values of k_IMD,HO● and k_AMT,HO● were (3.51?±?0.06)?×?10⁹ and (4.97?±?0.37)?×?10⁹ L mol^?1 s^?1, respectively, while different rate constants were obtained using anthraquinone-2-sulfonate (AQ2S) or 4-carboxybenzophenone (CBBP) as CDOM proxies. For IMD this difference was significant, with k_IMD,3AQ2S*?=?(1.02?±?0.08)?×?10⁹ L mol^?1 s^?1 and k_IMD,3CBBP*?=?(3.17?±?0.14)?×?10⁸ L mol^?1 s^?1; on the contrary, the values found for AMT are close, k_AMT,3AQ2S*?=?(8.13?±?0.35)?×?10⁸ L mol^?1 s^?1 and k_AMT,3CBBP*?=?(7.75?±?0.80)?×?10⁸ L mol^?1 s^?1. Based on these results, mathematical simulations performed with the APEX model for typical levels of water constituents (NO₃^?, NO₂^?, CO₃^2?, TOC, pH) indicate that the half-lives of these pesticides should vary between 24.1 and 18.8 days in the waters of the Paranapanema River (São Paulo, Brazil), which can therefore be impacted by intensive agricultural activity in the region.

     

Environmental biogeochemical behaviors of rare earth elements in soil–plant systems

With the continual increase in the utilization of rare earth elements (REEs) for industrial and agricultural purposes in China, the research into the environmental biogeochemical behavior of REEs has become a pressing issue. The REEs’ content in soil and various parts of wheat under different conditions in soil–plant systems were measured by INAA and ICP-MS. The results showed four aspects. (1) The mean value of total REEs in soil of China was 176.8 mg kg⁻¹. The mean ratio of ΣLREE/ΣHREE in soils was 8.0 and cerium accounts for 42% of the total REEs. The content of REEs in wheat seed ranged between 10⁻¹¹ and 10⁻⁸ g g⁻¹, 3–4 orders of magnitude lower than that in soil. (2) The REEs contents in ryegrass, especially in roots, were significantly related to that of soil. The bioavailability of REEs in soil mainly depended on the exchangeable fraction of REEs, which was strongly affected by the physico–chemical properties of the soil. (3) Long-term foliage-dressing with Changle microfertilizer of REEs did not affect the contents and distribution patterns of REEs in soil. At the maturing stage of spring wheat, the REEs content was in the order of root > leaf >stem and crust. Compared with the control, foliage-dressing has a higher accumulation of REEs in root and leaf. However, no significant difference was found in stem and crust between the two treatments. (4) There was no significant accumulation with the soil-dressing method. When comparing controls in both foliage- and soil-dressing methods, no distinct residue of REEs in grains was found.