克螨特和霸螨灵及其混剂在水中的光降解

研究了克螨特、霸螨灵在几种水体中的光降解以及 2种农药之间的光敏化或光猝灭效应。结果表明 ,在 3 0 0W高压汞灯光照处理时 (试验试管距光源 8cm) ,克螨特和霸螨灵都极易降解 ,克螨特的光解半衰期为 9.0 6min ,霸螨灵的光解半衰期仅为 1 .4 8min。克螨特在不同水体中的光解率为 :重蒸馏水 >鱼塘水 >河水 >井水 ,霸螨灵的光解率为 :井水 >重蒸馏水 >鱼塘水 >河水 ;2种农药在现采水、过滤水、灭菌水中的光解率依次降低。克螨特和霸螨灵混剂在重蒸馏水中互为光猝灭剂 ,在井水、河水和塘水中霸螨灵对克螨特有极显著的光敏化作用 ,而克螨特对霸螨灵有极显著的光猝灭效应。克螨特、霸螨灵在pH 5和 pH 9缓冲液中光解率比之在 pH 7缓冲液中稍快 ,光猝灭效应也较强烈。在重蒸馏水中太阳光照处理时 ,克螨特和霸螨灵互为光敏剂 ,而高压汞灯下则互为光猝灭剂。     

论中国山水画与古典园林的关系

中国山水画与古典园林相互之间关系密切.在历史上几乎都是相互制约、相互推进.在现代园林启蒙完成之时,重新研讨中国山水画与古典园林,取其精华,去其糟粕,对园林的现代化具有特别的意义.     

Movements of dispersing flying squirrels in relation to siblings and parents

Knowledge of kin interactions can be informative in explaining the processes underlying dispersal. By dispersing, relatives can avoid kin competition for resources or mates and prevent inbreeding. We investigated sibling movements in relation to each other and parents before and after dispersal in radio-collared juvenile flying squirrels (Pteromys volans L.). Before dispersal, most siblings moved in different areas and were not in contact while exploring the surroundings of natal area. After dispersal, all siblings settled far away from each other, as they dispersed different distances and to random directions compared to each other. No clear effect of litter size or presence of same-sex siblings was observed on dispersal. Time spent in the same nest with the mother did not differ between dispersing sons and daughters. Mother did not force dispersers to leave the natal nest; instead, the mother often moved away from the nest before offspring. Father and offspring were not observed to be in contact before dispersal. Dispersal direction was unaffected by the location of fathers’ home range. We conclude that after dispersal interaction between relatives is limited in flying squirrels, but we did not find any indication that interaction between relatives before dispersal is determining dispersal decision. Siblings’ settlement far away from each other was already indicated by the movement within the natal home range, but, interestingly, the latter could not be used to predict dispersal patterns of sexes.     

The measurement of nitrate and nitrite content in carrots and onions sampled from central cities of Mazandaran State of Iran

Vegetables are the major source of nitrates and nitrites in human diet. Because of the potential of health hazards resulting from high intake of nitrates and nitrites, the assessment of these components in vegetables was undertaken in this study. The concentration of nitrates and nitrites in carrots and onions sampled from three central cities of Mazandaran state (Iran) was determined in 12 samples of each vegetable collected from farmlands of four geographical regions in each city using the ISO Method (NO. 6635). The average content of nitrates and nitrites in all of the samples was less than standard threshold limits. Babol-sampled carrot had significantly higher nitrate content than two other cities. On the other hand, onions which were sampled from Sari showed significantly higher content of nitrate than two other cities. Based upon the maximum levels that were specified by European Commission Regulation, data showed that the investigated vegetables were safe for consumption.     

Social relationships in a cooperatively polyandrous group of tamarins (Saguinus fuscicollis)

Summary This paper presents detailed data on the social relationships among the adults, and between the adults and young, of a cooperatively polyandrous saddle-back tamarin (Saguinus fusciollis; Callitrichidae) group studied for one year. Some data are also presented from groups studied in other years. Adult males in the study groups gave more grooming than they received, while the opposite was true for females (e.g. Fig. 1). The two polyandrous males in the main study group were very rarely aggressive to each other, rarely tried to disrupt each others' copulations, groomed each other, and occasionally shared food, suggesting that their relationship was more affiliative than agonistic. Data on grooming (Fig. 2), spatial relationships, and the initiation of copulations suggest that the males of this group, may have been somewhat more responsible than the female for the maintenance of male-female relationships. Both males and females performed all forms of parental care except lactation. In the main study group each of the males groomed the offspring and remained in close proximity to them more than did the female (Figs.3 and 4). These data are compared with existing data on social relationships in bird species that exhibit cooperative polyandry.     

The Biodiversity Integrity Index: An Illustration Using Ants in Western Australia

Although Western Australia is a relatively unpopulated region, considerable areas of native vegetation have been modified by agricultural clearing, rangeland grazing, urbanization, road construction, and mining. Ant diversity is reduced and community composition changed by each of these land uses. Road construction has the greatest long-term effect on the alpha diversity of ants, followed by agricultural clearing, mining, urbanization, and rangeland grazing. We present data on the extent of these various land uses in each major Western Australian vegetation association. Then, examples of ant diversity and community composition for each land use are coupled with geographic information system data on the extent of each land use in the various vegetation associations to calculate indices of "biodiversity integrity." The extent of biodiversity integrity in each region concurs with a subjective opinion of the condition of each unit. Agricultural clearing, followed by rangeland grazing, were found responsible for the greatest loss of ant biodiversity integrity. The findings relate to Australia in general and may serve as a framework for estimating losses of biodiversity integrity in other regions of the world in taxa other than ants.     

The social network structure of a wild meerkat population: 1. Inter-group interactions

Groups of individuals frequently interact with each other, but typically analysis of such interactions is restricted to isolated dyads. Social network analysis (SNA) provides a method of analysing polyadic interactions and is used to analyse interactions between individuals. We use a population of 12 groups (ca. 250 animals) of wild meerkats (Suricata suricatta) to test whether SNA can also be used to describe and elucidate patterns of inter-group interactions. Using data collected over 24 months, we constructed two sets of networks, based on direct encounters between groups and instances of roving males visiting other groups. We analysed replicated networks of each type of interaction to investigate similarities between networks of different social interactions as well as testing their stability over time. The two network types were similar to each other when derived from long-term data, but showed significant differences in structure over shorter timescales where they varied according to seasonal and ecological conditions. Networks for both types of inter-group interaction constructed from data collected over 3 months reliably described long-term (12- and 24-month) patterns of interactions between groups, indicating a stable social structure despite variation in group sizes and sex ratios over time. The centrality of each meerkat group in roving interactions networks was unaffected by the sex ratio of its members, indicating that male meerkats preferentially visit geographically close groups rather than those containing most females. Indeed, the strongest predictors of network structure were spatial factors, suggesting that, in contrast to analyses of intra-group interactions, analyses of inter-group interactions using SNA must take spatial factors into account.     

A comparison of periodic survey designs employing multi-stage sampling

Sampling designs considered for a national scale environmental monitoring programme are compared. Specifically, design strategies designed to monitor one aspect of this environmental programme, agro-ecosystem health, are assessed. Two types of panel survey designs are evaluated within the framework of two-stage sampling. Comparisons of these designs are discussed with regard to precision, cost, and other issues that need to be considered in planning long-term surveys. To compare precision, the underlying variance of a simple estimator of mean difference is derived for each of the two designs. A variance and cost model accounting for the different rotational sampling schemes across designs are developed. Optimum stage allocation for each design are assessed with the variance-cost models. The best choice of design varied with the conditions underlying the variance model and the degree of other sources of survey error expected in the programme.     

Development of a PCR strategy for thraustochytrid identification based on 18S rDNA sequence

The identification and characterization of the thraustochytrids, an emerging economically and biotechnologically important group of marine heterotrophic protists, is usually based on morphological characters. In this research we used molecular markers to identify thraustochytrids. We designed three sets of primers based on the 18S rDNA sequence alignment of known strains and employed a PCR (polymerase chain reaction) strategy to identify unknown thraustochytrid isolates. DNA from 26 thraustochytrids (three isolated from primary cell cultures of the tunicate Botryllus schlosseri and 23 from a coral holding aquarium) were amplified by these primers, revealing 21 isolates with three bands each, which were assigned to two groups according to PCR fragment sizes. Taxonomic characterizations were deduced by comparing with GenBank data. Four isolates were further studied by sequencing their 18S rDNA. Sequence alignments and phylogenetic analysis revealed that isolates from the coral aquarium (7-5 and 8-7) were highly similar to each other and 95.0-97.0% similar to Thraustochytrium multirudimentale and Schizochytrium minutum. Isolates from the tunicate primary cell cultures (BS1 and BS2) were also closely related to each other and 84.3-86.0% similar to labyrinthulid quahog parasite and Thraustochytrium pachydermum. AFLP (amplified fragment-length polymorphism) analysis revealed 2.5-3.6% differences within the genomic DNA of each group, showing that each isolate is different, although isolates within each group may belong to the same species, in spite of differences found in the general morphology.     

Drivers of inter-year variability of plant production and decomposers across contrasting island ecosystems

Despite the likely importance of inter-year dynamics of plant production and consumer biota for driving community- and ecosystem-level processes, very few studies have explored how and why these dynamics vary across contrasting ecosystems. We utilized a well-characterized system of 30 lake islands in the boreal forest zone of northern Sweden across which soil fertility and productivity vary considerably, with larger islands being more fertile and productive than smaller ones. In this system we assessed the inter-year dynamics of several measures of plant production and the soil microbial community (primary consumers in the decomposer food web) for each of nine years, and soil microfaunal groups (secondary and tertiary consumers) for each of six of those years. We found that, for measures of plant production and each of the three consumer trophic levels, inter-year dynamics were strongly affected by island size. Further, many variables were strongly affected by island size (and thus bottom-up regulation by soil fertility and resources) in some years, but not in other years, most likely due to inter-year variation in climatic conditions. For each of the plant and microbial variables for which we had nine years of data, we also determined the inter-year coefficient of variation (CV), an inverse measure of stability. We found that CVs of some measures of plant productivity were greater on large islands, whereas those of other measures were greater on smaller islands; CVs of microbial variables were unresponsive to island size. We also found that the effects of island size on the temporal dynamics of some variables were related to inter-year variability of macroclimatic variables. As such, our results show that the inter-year dynamics of both plant productivity and decomposer biota across each of three trophic levels, as well as the inter-year stability of plant productivity, differ greatly across contrasting ecosystems, with potentially important but largely overlooked implications for community and ecosystem processes.     

Mechanisms of arsenic removal from water

In this review paper, various methods for arsenic removal from water have been described by explaining the related mechanisms of each methods. Advantages and drawbacks were discussed. Membrane methods were suggested as reliable methods for elimination of arsenic from water in addition to other conventional separation methods.     

Choice of Species-Area Function Affects Identification of Hotspots

Abstract: I tested the reliability of species-area curves for use in identifying hotspots, political or geographical regions of high species richness. On a species-area plot, hotspots are points (regions) that appear above the curve to a greater extent than other points. Because several different curves can be fit to species-area data, identification of hotspots may differ depending on the curve-fitting function used. I tested this hypothesis by comparing hotspots identified by the power function, the extreme value function, a linear function, and the exponential function. I examined several species-area data sets varying in size and in the presence of endemics. I defined hotspots as the highest 25% for small data sets and highest 10% and 25% for large data sets of standardized residuals from each function fitted to each data set. For some data sets, the functions agreed in identification of hotspots in that they identified 75% or more of the same hotspots. The extreme value function tended to identify hotspots not identified by the other three functions. For most data sets, the functions did not agree completely in identifying hotspots. Therefore, species-area curves should not be used as the sole means of identifying hotspots of species richness, although they can be used to examine the effect hotspot area has on richness for hotspots identified by other methods.     

Nontransitive patterns of historecognition phenomena in the Red Sea hydrocoral Millepora dichotoma

Allogeneic assays were conducted in situ on the Red Sea hydrocoral Millepora dichotoma. Forty-five pairwise combinations among ten colonies and ten control isografts were set up in four replicates each (180 and 40 pairs, respectively) and followed for up to 8 mo in the Gulf of Eilat, Red Sea in 1992–1993. In 42 allogeneic combinations we recorded a reproducible and unilateral tissue and skeleton overgrowth which developed within the first 10 wk up to 20 mm. Following the development of these primary overgrowths, four types of secondary responses were observed among most incompatible combinations: reversals in overgrowth directionality, tissue necroses, stand-offs and abnormal growth patterns. Secondary responses within a given set of replicates of most allogeneic combinations were characterized by high variability in type and intensity of response. Based on the outcomes of primary overgrowths, a complex nontransitive hierarchy was constructed for the ten colonies. All isografts and three allogeneic combinations fused within 3 wk. Fusion pattern between the three allogeneic combinations was nontransitive: one M. dichotoma colony repeatedly fused with two other colonies (four assays each). However, these two colonies not only did not fuse with each other, but one of them repeatedly overgrew its confrére. In the third compatible combination, the most superior and the most inferior colonies in the network of hierarchies among the ten colonies, fused in all tested assays. These results are compared with allogeneic outcomes in other enidarians, where nontransitive fusion between allogenic colonies have never been recorded.     

氯乙烯生产中的清洁生产分析

结合氯乙烯清洁生产中存在的实际问题,重点对氯乙烯工业生产全过程涉及的工艺技术路线与技术装备的先进性进行分析。通过不同生产工艺的纵向比对,及先进工艺的不同专利技术间的横向对比,对氯乙烯的生产工艺进行清洁生产的分析与评价。     

A new heuristic for capturing the complexity of multimodal signals

Many animal signals are inherently multimodal, engaging more than one of the receiver’s sensory systems simultaneously, and it is the interaction between the two modalities that determines the signal’s function (s) and efficacy. It is hence necessary to quantify the effect of each modality relative to the other in order to fully understand animal communication. We have developed a new heuristic to aid in the identification and interpretation of the many distinct ways in which signals in multiple sensory modalities interact. Our approach represents natural variation in signal production for each modality and uses these to generate three-dimensional receiver response surface plots that map the relationships among the signal components and receiver behavior. We accommodate the extant hypotheses for the interactions between modalities, each of which makes a clear prediction about the shape of the response surface, and extend previous theory by considering new phenomena.     

The fatty acids of antarctic phytoplankton and euphausiids. Fatty acid exchange among trophic levels of the Ross Sea

The fatty acids of 3 samples of Euphausia superba, 7 samples of E. crystallorophias, and 12 samples of phytoplankton collected in the Ross Sea, Antarctica, during Eltanin Cruise 51 were examined. The fatty acid profiles of the samples of E. superba resembled each other closely. The fatty acid profiles of the E. crystallorophias samples were also similar to each other but different quantitatively from those of E. superba. Phytoplankton fatty acid patterns varied with the geographical location and species composition of the samples. The fatty acids of euphausiids were compared to those of the phytoplankton from the corresponding locations. Rather similar fatty acid patterns in phytoplankton and E. superba corroborate the herbivorous nature of this euphausiid. On the other hand, phytoplankton and E. crystallorophias showed quite different fatty acid patterns. The differences were mostly due to the presence of waxes among the lipids of E. crystallorophias. It is not clear whether these waxes are of dietary origin or are synthesized endogenously.     

Spatio-temporal variations in megabenthos abundance in three different habitats of the Catalan deep-sea (Western Mediterranean)

The spatio-temporal variations in the megafauna (fishes, crustaceans, and other invertebrates) in three different habitats on the slope in the Western Mediterranean (Catalan coast off Barcelona) have been investigated. Samples were collected at two fixed stations during 1991 and 1992, one inside and one outside a submarine canyon (at depths between 450 and 600 m) and additional samples were collected at another station on the lower slope (at a depth of 1200 m) in each season of the year. Three replicates of each sample were taken at each station. Differences observed between habitats, seasons, and zoological groupings were verified statistically by factorial ANOVA. The habitat appeared to be the main factor responsible for the differences observed in biomass and abundance values for the zoological groupings considered. Decapod crustacean biomass was higher in the submarine canyon than in neighbouring zones, and smaller species and juveniles were more abundant inside the canyon in the case of both fishes and crustaceans. Fish biomass was most abundant in the lower slope. Seasonality was also a factor, although to a lesser extent. Seasonal variations in biomass, especially fish biomass, were recorded in the deepest zone (1200 m). Crustaceans displayed lower sensitivity to seasonal factors, whereas other invertebrates did not, on the whole, exhibit seasonal variations.     

Distribution of lipopolysaccharide,an indicator of bacterial biomass,in subtropical areas of the sea

Lipopolysaccharide (LPS) concentrations, an indicator of bacterial biomass, were determined in the South China Sea and the Pacific Ocean. The distribution patterns of LPS were compared with those of chlorophyll a (Chl a), zooplankton biomass and the concentrations of several nutrients. LPS and total bacterial numbers in seawater were correlated with each other with a correlation coefficient (r) of 0.84 at Stations 7, 8 and 10. Diurnal fluctuation of LPS was negligible, but Chl a varied slightly in the vertical water column. Zooplankton stayed at a depth of around 400 m during the daytime and ascended quickly to the surface (0–50 m) early in the evening. The profiles of LPS and Chl a were negatively correlated to each other in the water layers above the Chl a maximum peak (r=-0.74; excluding the samples from 75 m at Station 7 and 10 m at Station 11 due to inadequate data for the statistical analysis). LPS and zooplankton biomass during the night-time, in contrast, paralleled each other at 5 stations surveyed (r=0.71). The presence of zooplankton resulted in an increase in bacterial numbers in the seawater in vitro. Based on these results, the factors controlling the occurrence and abundance of bacteria and phyto- and zooplankton in the pelagic sea are discussed.     

Genetic monogamy in the common loon (Gavia immer)

We conducted behavioral observations and genetic analysis on breeding pairs of common loons in the upper Great Lakes region from 1993 through 1995 to look for behavioral evidence of extrapair copulations (EPCs) and to determine parentage of young. Pairs remained close to each other (usually within 20 m) during the pre-laying period, leaving little opportunity for EPCs to occur. Males and females both maintained physical proximity by approaching each other when they became separated. Copulations were obvious but infrequent, occurring about once every other day during the pre-laying period. Multilocus DNA fingerprinting was consistent with behavioral findings: 58 young from 47 different families were all genetic offspring of parents that raised them. Perfect genetic monogamy (genetic parentage of young by parents that rear them) in loons might arise as a consequence of the need for vigorous territorial defense to prevent territorial takeover. Received: 8 August 1996 / Accepted after revision: 22 March 1997     

Worker policing and nest mate recognition in the ant <Emphasis Type="Italic">Formica fusca</Emphasis>

A conflict over male production arises in social insects where workers are able to lay unfertilized male eggs. This happens because each female (queen or worker) is most closely related to her own sons and is thus predicted to reproduce. The conflict is modulated by worker policing where workers prevent each other from reproducing by aggression or egg cannibalism. In this study, we show that in the ant Formica fusca, worker policing occurs by egg cannibalism rather than by overt aggression among workers. Furthermore, we show that, contrary to bees, wasps and other ant species, egg discrimination in F. fusca is not based only on a universal queen signature chemical and that nest mate recognition of eggs occurs.