CEA in policies and plans: UK case studies

This paper examines how cumulative effects assessment (CEA) has been considered in Strategic Environmental Assessments (SEA) of regional and local plans in a number of case studies in the UK. Initially, the paper presents the legislative and regulatory requirements for assessing cumulative effects in plans and programmes in the UK. The two approaches for assessing plans in the UK, Sustainability Appraisal (SA) and SEA are discussed and in most cases, a combined SA and SEA process is undertaken by Regional and Local Planning Authorities. The strengths and weaknesses of this approach are explored, as well as their usefulness in decision making. There are problems relating to baseline, establishing trends and predicting cumulative effects at the strategic level. The issues in assessing cumulative effects within this SA/SEA framework are discussed and recommendations for improvements are made.     

Water, Endangered Fishes, and Development Perspectives in Arid Lands of Mexico

Nearly half of Mexico is arid or semiarid, with scarce waters. At least 92 springs and 2500 km of river have dried in this area. Surface waters have diminished, and phreatic waters are sinking deeper, provoking intrusion of saline waters and salinization of agricultural wells in Sonora, reversing phreatic circulation in the Comarca Laguenera, allowing arrival of arsenic to agricultural waters, and threatening metropolitan Torreón. There are nearly 200 species of freshwater fishes in this region, 120 under some threat, 15 extinct through human impact. As of 1985, an average of 68% of species was eradicated in local fish faunas. Finally, salinization of the lower Rio Bravo del Norte has replaced 32 native fish of fresh or slightly brackish water with 54 mainly marine or highly salt-tolerant species; the salinization threatens all uses of water. Some marine fishes invade up to 400 km upstream. Pollution is strong, and fish kills have been reported. These low-quality and scarce waters comprise future resources for cities such as Monterrey, which, along with its border twin cities, is expected to double its human population by 2010. Redesign of regional development is urgently needed, in keeping with the real availability of water. All water use should be equal to or less than lower recharge averages; norms of integral basin management should rely on criteria of high-use efficiency, recuperation, recycling, and reutilization. Also necessary are reduced pollution and increased treatment of residual waters. Innovative environmental vision is especially essential in light of expectations for development through the North American Free Trade Agreement, the Border Integral Environmental Plan, industrial expansion, and the modernization and internationalization of the northern Mexican border belt. These all conflict with the high priority recently decreed for species conservation by the Mexican Act, creating the National Committee on Knowledge and Use of Biodiversity.     

Photocatalytic degradation of paraquat using nano-sized Cu-TiO2/SBA-15 under UV and visible light

Photocatalytic degradation of paraquat using mesoporous-assembled Cu-TiO₂/SBA15 under UV and visible light was investigated. The catalyst was synthesized by impregnation of Cu-TiO₂ colloids onto SBA-15. The colloids of Cu-TiO₂ were prepared via sol-gel method while the mesoporous support was prepared using hydrothermal technique. The catalyst was characterized using X-ray diffraction, nitrogen adsorption-desorption, transmission electron microscopy, UV diffuse reflectance spectroscopy, Zeta potential and X-ray adsorption spectroscopy. Results from characterizations showed that Cu doped TiO₂ had a small crystalline size and was well-dispersed on SBA-15. The inclusion of SBA-15 significantly enhanced the photocatalytic activity of the catalyst. Among the three types of undoped catalyst in this study (P25, TiO₂, TiO₂/SBA-15), TiO₂/SBA-15 yielded the highest degradation of paraquat for all pH under UV illumination. Meanwhile 2 wt.% Cu-TiO₂/SBA-15 yielded the highest activity under visible light.     

What can the Allium cepa test say about pesticide safety? A review

Environmental Science and Pollution Research - The increasing use of pesticides has caused global concerns about the toxic effects and adverse consequences of pesticides on humans and the...     

Attraction of entomopathogenic nematodes to sugarcane root volatiles under herbivory by a sap-sucking insect

Few systems have been described in which herbivore-induced root volatiles mediate attraction of entomopathogenic nematodes (EPNs), and they only concern root damage inflicted by chewing insects. EPNs, especially Heterorhabditis indica and Steinernema carpocapsae, are potential biological control agents of sugarcane spittlebug (Mahanarva fimbriolata) populations. Here, we investigated the response of these two species of EPNs to sugarcane root volatiles damaged by M. fimbriolata nymphs in a belowground six-arm olfactometer. We also examined changes on root volatile profile in response to herbivory of sugarcane spittlebug nymphs. Results showed that both EPN species did not discriminate between odors of undamaged sugarcane and moistened sand (blank). However, when EPNs were exposed to odors of spittlebug-damaged and undamaged sugarcane roots, both species significantly preferred odors of spittlebug-damaged roots. Headspace collection followed by GC–MS analyses showed no qualitative difference (total of 11 compounds) between volatile profiles of spittlebug-damaged and undamaged sugarcane roots. In contrast to the previous studies involving feeding by root chewing insects, our root volatile analysis did not reveal any up-regulation resulting from sugarcane spittlebug damage, but the down-regulation of the terpenes dihydromyrcenol and β-isomethyl ionone when compared with the profile of undamaged sugarcane roots. Here, we propose alternative explanations for the EPN attraction to spittlebug-damaged roots as it is unlikely that reduced concentrations of the volatiles play a role in this interaction. Further studies are necessary to determine the key compounds of the root volatile emission to enhance biological control efficacy with EPNs against M. fimbriolata in sugarcane.     

Short- and long-term importance of small sharks in the diet of the rare deep-sea shark Dalatias licha

Knowing the trophic ecology of marine predators is essential to develop an understanding of their ecological role in ecosystems. Research conducted on deep-sea and threatened shark species is limited. Here, by combining analyses of individual stomach contents and stable isotope values, we examined the trophic ecology (dietary composition and trophic position) of the kitefin shark Dalatias licha, a deep-sea shark considered as near threatened globally and as data deficient in the Mediterranean Sea. Results revealed the importance of small sharks in the diet of the kitefin shark at short- and long-term scales, although fin-fish, crustaceans and cephalopods were also found. Predation on sharks reveals the high trophic position of the kitefin shark within the food web of the western Mediterranean Sea. Stable isotope values from liver and muscle tissues confirmed our results from stomach content analysis and the high trophic position.     

Perceptions regarding the challenges and constraints faced by smallholder farmers of vanilla in Mexico

Mexico was the main vanilla producer worldwide many years ago. However, it currently provides just around 5 % of the global production. The issues that have led to the current stagnation of the vanilla production in Mexico have been addressed from various perspectives, but few studies have included the opinion of smallholder farmers. For this reason, the aim of this study was to conduct a participatory diagnostic to identify the challenges and constraints that affect the vanilla productive sector in Mexico from the smallholder farmers perspective. This study was conducted under the of Participatory Rural Appraisal (PRA) approach; consequently, we used PRA techniques for data collection. The qualitative data obtained were transcribed and analyzed using the Content Analysis Method (CAM) and Constant Comparative Method (CCM). The results showed that most of the challenges and limitations referred to by smallholder farmers result from the lack of training to improve production, processing, and marketing. Likewise, various restrictive aspects were identified in the production process that affect crop productivity, such as cultivation in small parcels, high incidence of diseases, premature abortion of fruits, and low tolerance of plants to stress. An aspect common to all processes is the need to promote organization and training schemes, since under the conditions described for the vanilla production chain in Mexico, relationships have been built in highly competitive communities and, in general, the targets seek have been mutually exclusive. For the above, we consider that achieving more profitable and sustainable production schemes require placing smallholder farmers at the base of an inclusive production system supported by fair trade, with organization, institutions, technology transfer, level of trust, and cooperation as core elements.     

Toxic potential of the emerging contaminant nicotine to the aquatic ecosystem

Nicotine is a “life-style compound” widely consumed by human populations and, consequently, often found in surface waters. This fact presents a concern for possible effects in the aquatic ecosystems. The objective of this study was to assess the potential lethal and sublethal toxicity of nicotine in aquatic organisms from different trophic levels (Vibrio fischeri, Pseudokirchneriella subcapitata, Thamnocephalus platyurus, and Daphnia magna). The bioassays were performed by exposing the organisms to concentrations of nicotine in a range of 0.5–1000 μg/L. Results showed that nicotine, at tested concentration, was not acutely toxic to V. fischeri and T. platyurus. On the contrary, this substance exhibited toxicity to P. subcapitata and Daphnia magna. Thus, concentrations of nicotine of 100 and 200 μg/L promoted an inhibition in the growth of P. subcapitata. In addition, a concentration of 100 μg/L nicotine acted on the reproduction of the crustacean D. magna, by decreasing the number of juveniles produced by female. On the other hand, the results showed that concentrations equal to or greater than 10 μg/L induced the production of daphnids male offspring, which may indicate that nicotine is a weak juvenoid compound of the D. magna endocrine system. Furthermore, the result showed that concentrations tested of this chemical have the capacity to revert the effect of fenoxycarb, a strong juvenoid chemical insecticide. The results of the study revealed that nicotine can induce several changes in some of the most important key groups of the aquatic compartment, which can compromise, in a short time, the balance of aquatic ecosystem. Finally, a preliminary environmental risk assessment of this stimulant was performed from the highest measured concentration in surface water and the no observable effect concentration value in the most sensitive species, i.e., D. magna. This process revealed that nicotine can produce an important risk to aquatic organisms.