Eco(nomics/logy)

This note discusses the analytic tools available for studying the interrelations between the economy and the ecological system. It points out the importance of the concept of cooperative games as an addition to the emphasis on non-cooperative games in both economics and ecology. The relation between both concepts of the games and the market system is discussed.     

Molecular study of the genus Astraeus

The aim of the present work was to determine phylogenetic relationships among Astraeus species and to support macroscopic and microscopic characters of Astraeus with analysis of the ITS rDNA region. Collections of Astraeus basidiomes were made from different geographical areas in Thailand and compared with existing collections made worldwide. The marriage of observations on morphological features, including basidiospore ornamentation and molecular data demonstrated the presence of several Astraeus species. Sequences for 41 Astraeus collections were compared and the phylogenetic analyses grouped Thai Astraeus collections into two distinct groups. One contained A. odoratus and an Asian species described herein as A. asiaticus. There are at least two additional species: A. pteridis, and one so far un-named from North America. Our results show that molecular data can be used in combination with traditional morphological characteristics to resolve taxonomic uncertainties in the genus Astraeus.     

Depth-related changes to density,diversity and structure of benthic megafaunal assemblages in the Fimbul ice shelf region,Weddell Sea,Antarctica

The depth-related patterns in the benthic megafauna of the NE Weddell Sea shelf at the edge of the Fimbul Ice Shelf were investigated at seven sites using towed camera platform photographs. Megafaunal density decreased with depth from 77,939 ha⁻¹ at 245 m to 8,895 ha⁻¹ at 510 m. While diversity was variable, with H′ ranging between 1.34 and 2.28, there were no depth related patterns. Multivariate analyses revealed two distinct assemblages; a shallow assemblage with dense patches of suspension feeders in undisturbed areas and a deep assemblage where these were not present. Disturbance from icebergs explained many observed patterns in faunal distribution. In shallow waters probable effects of disturbance were observed as changes in successional stages; in deeper waters changes in habitat as a result of past disturbance explained faunal distributions. In deeper areas ice ploughing created a mosaic landscape of fine and coarse sediments. Total megafaunal density was highest in areas of coarse sediment (up to 2.9 higher than in finer sediment areas) but diversity was highest in intermediate areas (H′ = 2.35).     

浙江丽水生态示范区植物的分布特点

1999年底被国务院批准设立为全国第4个生态示范区的丽水市（包括莲都区,缙云县,云和县,松阳县,遂昌县,庆元县,青田县,龙泉市和景宁畲族自治县）,由于地形复杂,原生,次生林等保存较好,生态环境保持良好,植物资源极为丰富。笔者根据多年来对该地区的资源调查和标本采集统计,已知有维管束植物206科,94属,2881种,其中蕨类植物的种类和数量在中国东半部仅次于台湾和海南,尤其是鳞毛蕨属和复叶耳蕨属可以认为是在我国的一个分布中心,种子植物的种类和数量与邻近周边地相比也占有明显优势,区内珍衡濒危植物众多,区系起源古老,不乏古老的种,属及残遗种,且区系成分复杂,来源于多种地理成分。     

Comparative ecological analysis of Toarcian (Lower Jurassic) benthic faunas from southern France and east-central Spain

Toarcian (Lower Jurassic) argillaceous-marly sediments of southern France (Causses) and east-central Spain (Barranco de la Puta section) were deposited in mid to lower shelf settings. They contain a low to moderately diverse, autochthonous fauna of benthic macroinvertebrates dominated by bivalves and gastropods, in the case of the Causses, and by bivalves and brachiopods in the Barranco de la Puta section. Five benthic associations are recognized at the latter locality and four at the former. In the Causses, low species diversity, evidence of seasonal mass mortality, presence of the opportunistic bivalve Parvamussium pumilum, local dominance of the soft bottom coral Thecocyathus mactrus and the dark-grey, fine-grained sediment point to high rates of sedimentation, high turbidity, intermittently lowered oxygen values and soft to soupy substrate conditions. These factors, together with eutrophic water masses, were the main environmental parameters governing faunal distribution. Soupy substrate conditions are thought to be largely biologically produced by the activity of infaunal depositfeeders, chiefly nuculoid bivalves. In the Barranco de la Puta section, abundant brachiopods, higher carbonate content of the sediment, and evidence of intermittent in-situ reworking and winnowing point to an influence of storm-induced currents, a shallower depositional depth, lower turbidity, a lower rate of sedimentation, and a somewhat firmer substrate. As a consequence, the fauna is largely dominated by epifaunal suspension-feeders. Compared with maximum and average sizes from elsewhere in the Jurassic, most bivalve species are distinctly smaller, a feature interpreted as stunting. Brachiopods, in contrast, reach normal size. The lack of nuculids, scarcity of deposit-feeders in general, and stunting are interpreted as evidence of an oligotrophic environment. Lowered oxygen conditions appear to have played only a very limited role in shaping the distribution pattern. Many of the differences between both areas can be explained by the different trophic regimes that reflect considerably higher run-off and consequently higher input of terrigenous sediment and dissolved nutrients to the basin in the case of the Causses. This in turn is thought to possibly reflect differences in regional climate; humid in southern France and more arid in eastcentral Spain.     

Volatile compounds from Liposcelis bostrychophila (Psocoptera: Liposcelididae) and their environment and their effects on settling behaviour

Headspace from above either Liposcelis bostrychophila Badonnel reared on powdered food; insects without food or from powdered food only were collected on five occasions over a period of four weeks. Volatiles were analysed by thermal desorption gas chromatography-mass spectrometry (TD-GCMS) to look for ecologically significant volatile compounds. Hexanoic acid (HA) was the major compound in the insect only and diet only volatiles (insect 25.6 ± 1.6%, diet 32.9 ± 1.13%). Isobutyric acid was the main compound detected in the volatiles from both insects and diet (35.3 ± 6%). Butyric acid (BA) and acetoin (HB) were also present at >2% of the total peak areas. HB was not detected in the insect only volatiles. Bioassays showed that hexanoic acid was the most repellent chemical. Mixtures of compounds representing the proportions of HA, BA, IBA, and HB in the volatiles did not have any prolonged effect on settling or selection by booklice in a two choice bioassay. L. bostrychophila can avoid individual volatile chemicals but the effects can be masked when they are incorporated into mixtures. As some volatile compounds can be detected by booklice they may govern dispersal, but further work is required to clarify their significance.     

Toxic strains of the Alexandrium ostenfeldii complex in southern South America (Beagle Channel,Argentina)

During phytoplankton monitoring in the Beagle Channel (≈54°52′ S, 67°32′ W) a previously undetected Alexandrium species was observed in coincidence with mouse bioassay toxicity. Detailed thecal plates analysis using epifluorescence and scanning electron microscopy revealed the presence of the Alexandrium ostenfeldii species complex, showing a mixture of the diagnostic features usually used to discriminate between the morphospecies A. ostenfeldii and A. peruvianum. Cells of the A. ostenfeldii complex were commonly observed during spring after the main annual diatom bloom, when temperatures and salinities were respectively around 7.5–10 °C and 30–30.5 psu, and nutrients showed a seasonal decrease. Toxin analysis by liquid chromatography–mass spectrometry revealed the production of 13-desmethyl spirolide C and 20-methyl spirolide G in cell cultures. The cellular contain of spirolides during exponential phase growth was 0.5906 ± 0.0032 and 0.1577 ± 0.0023 pg cell⁻¹ for 13-desMe-C and 20-Me-G, respectively. A third unknown compound, with a structure resembling that of spirolides was also detected in culture. Moreover, an additional compound with a similar m/z (692) than that of 13-desMe-C but presenting a higher retention time (Rt = 40.5 min) was found in high proportions in mussel samples. PSP toxins were present at low concentration in mussels but were not detected in cultures. These results extend the world-wide distribution of toxic strains of the A. ostenfeldii complex to the Beagle Channel (southern South America), where toxic events have been traditionally linked to the presence of Alexandrium catenella. This is the first confirmed occurrence of spirolides in mussels and plankton from Argentina, which highlights the importance of monitoring these toxins and their producing organisms to protect public health and improve the management of shellfish resources.     

Mating behaviour and behavioural ecology of a Predatory Wasp,Symmorphus allobrogus (de Saussure) (Hymenoptera: Eumeninae)

This paper represents an attempt to investigate the mating behaviour of Symmorphus allobrogus, explaining the willingness of male to mount and copulate. The male displays including mode and frequency of antennation and position while copulating, the displays further comprises of intensity and frequency of rejecting behaviour. The presence of the male’s copulatory and postcopulatory courtship studies, understands the maintenance of monandry. The wasp has numerous secondary sexual characters, and the mating behaviour follows a phyletic and the specific sexual mating characters in context of sexual selection. The duration of mating phases and the number of male antennation series during precopulatory, copulatory and postcopulatory phases of mounting, differs significantly. Mating success depends mostly on the activities of male in the premounting phase and the behaviour of both sexes has a roughly equal importance for it in precopulatory phase. While during copulation, activity of male has little influence on its duration; however, behaviour of female has crucial effect, inducing its earlier termination.