Abstract

Despite a large amount of research into invasive species and their introductions, there have been no studies focused on macroalgal transport in ballast water. To address this, we collected replicate samples of ballast water from 12 ships in two Mediterranean harbours (Naples and Salerno). Filtered samples were kept in culture for a month at Mediterranean mean conditions (18 °C, 12:12 h LD, 60 μmol photons m⁻² s⁻¹). Fifteen macroalgal taxa were cultured and differed according to the geographic origin of the ballast water. Most of the cultured algae were widely distributed species (e.g. Ulva spp. and Acinetospora-phase). However, Ulva ohnoi Hiraoka and Shimada, described from Japan, was hitherto unknown in the Mediterranean Sea. We show for the first time that ballast water can be an important vector for the transport of microscopic stages of macroalgae and that this can be a vector for the introduction of alien species.

Abstract

The International Maritime Organization (IMO), the United Nations body which administers the international regulatory regime for shipping, noted the negative impact of non-indigenous organisms transported in the ballast water of ships already in the early 1970s. Consequently, measures were taken with the aim to minimize ballast water mediated species invasions through IMO Marine Environmental Protection Committee (MEPC) Resolutions. As a result of long-term IMO efforts, it was determined that an international convention would best meet the needs of the global community, hence the International Convention for the Control and Management of Ships’ Ballast Water and Sediments was adopted in a Diplomatic Conference in 2004 and is now open for signature by IMO Member States. This very complex (and by no means “simple”) Convention aims to reduce the transfer and subsequent impact of aquatic organisms in the ballast water and sediment of ships by acting to reduce the load of these organisms in discharged ballast water. A set of 15 guidelines provides technical guidance for the implementation of the Convention principles. This review considers critical aspects of this Convention and selected guidelines seen from perspectives of biological, shipping and regulatory concerns.

Two challenges faced by carbon membrane for application on commercial scale are its low permeability and poor mechanical strength. And it is attributed to the vermiform pore structures and special characteristics of carbon membranes. In order to solve these problems, methods such as choosing the precursors with suitable chemical structure and space mould, incorporating nanosize functional groups into precursors are employed to effectively change and improve the vermiform pore structures of carbon membranes and enhance the gas permeabilities of carbon membranes. The results indicate that the gas permeabilities of hybridized function carbon membranes are increased by 2 orders in magnitude without reducing the gas selectivity obviously. Besides, some functional carbon membranes have also revealed higher gas selectivity for some gases such as CO₂. The coalbased composite carbon membranes with high gas permselectivity are developed by dipcoating the precursors on the cheap coalbased supports invented by ourselves to improve the mechanical strength of carbon membranes.

气体渗透性低、机械强度差是炭膜产业化道路上的两大难题.研究发现，根源在于炭膜的蠕虫状孔道结构与均质炭膜的特有性质.为了解决炭膜渗透性低的问题，通过选择适宜的聚合物前驱体的分子结构与空间构型结合填充纳米粒子为功能基团等手段，实现对炭膜蠕虫状孔结构有效地调控与重新构建.在保证高选择性的条件下，不仅使炭膜的气体渗透性能提高了2个数量级以上，而且还使炭膜对某些气体具有较高分离选择性的功能化效果.为了改善炭膜的机械强度，将自主研发的廉价煤基炭膜支撑体与前驱体相复合，采用简单的制膜工艺，制备得到复合性能好、气体分离性能高的复合炭膜.