Molecular phylogeny and population structure of tideland snails in the genus Cerithidea around Japan

Phylogenetic relationships and genetic population structures were analyzed for tideland gastropods in the genus Cerithidea around Japan on the basis of partial sequence of the mitochondrial COI gene. Large genetic divergence was shown between individuals of Cerithidea cingulata in the southern Ryukyus and those in the central Ryukyus and the Japanese Islands. Haplotypes of C. cingulata from the Japanese Islands were paraphyletic with the exclusion of a monophyletic group from the central Ryukyus. Genetic differentiation of C. cingulata was also detected between Amami-Oshima Island and Okinawajima Island. No genetic divergence was found between Cerithidea rhizophorarum in the Japanese Islands and its subspecies C. rhizophorarum morchii in the Ryukyu Islands. The lack of genetic divergence of Cerithidea largillierti between continental China and Japan suggests relatively recent migration between the Japanese Islands and the Asian continent. For all three Cerithidea species distributed in both the Japanese Islands and the Ryukyu Islands, the Tokara Gap and the Kerama Gap were shown to have acted as barriers to the dispersal.     

灰色协调度模型在产业用水系统分析中的应用

揭示产业用水系统的时空动态发展规律，探讨其内部的协调关系，是开展节水型社会建设规划，实现水资源可持续利用的关键。然而，目前对产业用水系统的协调性分析还缺乏较为有效的理论和方法。以往在利用协调度模型进行用水系统有序度研究时，通常采用两段叙述的线性分段函数表示，较不适用于描述产业用水系统内部要素的非线性结构。因此，针对产业用水系统的特性，利用灰关联原理建立有序度函数，以建立更适于用水系统分析的灰色协调度模型。利用该模型对上海市1997~2005年产业用水系统进行实证研究，结果显示：上海市产业用水系统基本有序，发展比较协调，其用水综合效益较大，但距离最优状态尚有潜力可挖；其中，农业用水子系统的发展较为欠缺，在未来用水规划中应予以重视。     

Biodegradation of crosslinked acrylic polymers by a white-rot fungus

Two synthetic superabsorbent crosslinked acrylic polymers were mineralized by the white-rot fungusPhanerochaete chrysosporium. The amount of polymer converted to CO₂ increased as the amount of polymer added to the cultures increased. In the presence of sufficiently large amounts of the superabsorbents, such that all of the culture fluid was absorbed and a gelatinous matrix was formed, the fungus still grew and mineralization was observed. Neither the polymers, nor their degradation products were toxic to the fungus. While the rates of mineralization were low, all of the polymers incubated in the liquid fungal cultures were completely depolymerized to water soluble products within 15–18 days. The depolymerization of the polymers was observed only in nitrogen limited cultures of the fungus which secrete the lignin degradation system, however, the water soluble products of depolymerization were mineralized in both nutrient limited and sufficient cultures of the fungus. The rate of mineralization of the depolymerized metabolites was more than two times greater in nutrient sufficient cultures. Following longer incubation periods, most (> 80 %) of the radioactivity was recovered in the fungal mycelial mat suggesting that carbon of the polymer had been converted to fungal metabolites.     

Migration,habitat use,and competition among mobile corals (Scleractinia: Fungiidae) in the Gulf of Eilat,Red Sea

We examined the impact of seven species of mobile mushroom corals (Fungiidae) on the community structure of sheltered reef slopes in terms of their patterns of migration, habitat use and competition with other benthic organisms. On fringing reefs at Eilat, Red Sea, polyps detached at 1 to 6 cm length, and grew to 11–55 cm length. Attached mushroom corals were oriented vertically in reef cavities. Detached corals migrated downward on the reef slope and onto rubble or soft substratum at the reef base, at 29 to 71 cmyr^–1. Mobility decreased with corallum size and extent of undersurface ornamentation. In aquaria, small corals righted themselves and migrated up to 6 cm d^–1 by nocturnally inflating and pushing their tissues against the substratum. Autonomous coral behavior and storm-generated water motion appeared to account for most fungiid mobility at Eilat. Mushroom corals did not damage each other upon contact, even in multi-species aggregations, but unilaterally damaged non-fungiid scleractinian corals. Their dominance during contact interactions retards overgrowth by larger attached scleractinians, and mobility allows them to colonize soft substrata not accessible to most other reef corals.