Distribution and early life history of <Emphasis Type="Italic">Kaupichthys</Emphasis> leptocephali (family Chlopsidae) in the central Indonesian Seas

Leptocephali of the widely distributed tropical marine eels of the genus Kaupichthys (family Chlopsidae) were collected around Sulawesi Island during a sampling survey in the Indonesian Seas in late September and early October 2002, and the otolith microstructure of 24 of the 59 specimens captured was examined to learn about the larval growth rates and spawning times of these small sized eels. Leptocephali ranging in size from 25 to 60 mm were collected in Makassar Strait and the Celebes Sea, but they were most abundant in the semi-enclosed Tomini Bay of northeast Sulawesi Island. The Kaupichthys leptocephali examined had 39–161 otolith growth increments. Their back-calculated hatching dates indicated that five age groups were present and each group appeared to have been spawned around the full moon of previous months. Average growth rate estimates of the first two age groups were 0.65 and 0.54 mm/day for the 27.4–30.4 and 37.6–45.6 mm age classes. The growth rates of the oldest three age groups (52.0–60.8 mm) appeared to have slowed down after they reached their approximate maximum size. An increase in increment widths at the outer margin of the otoliths of those larger than 53 mm suggested that the process of metamorphosis had begun even though there were few external morphological changes indicating metamorphosis. It is hypothesized that chlopsid leptocephali have an unusually short gut that may not need to move forward during early metamorphosis. The presence of four age classes in Tomini Bay suggests that the Togian Islands region may be productive habitats for Kaupichthys juveniles and adults.     

Graphical spatial models: a new view on interpreting spatial pattern

Graphical models provide an important tool for facilitating communication between scientists, decision-makers, and statisticians—many complicated ecological processes can be described in terms of “box-and-arrow” conceptual diagrams (e.g., Shipley in Cause and correlation in biology: a user’s guide to path analysis, structural equations and causal inferences, Cambridge Universtiy Press, Cambridge, 2000; Clark and Gelfand TRENDS in Ecology and Evolution 21:375–380, 2006). In particular, problems in landscape ecology often involve modeling relationships among multiple physical and/or biological variables that may operate on differing spatial scales (e.g., Rossi et al. in Ecol Monographs 62:277–314, 1992; Legendre et al. in Ecography 25:601–615, 2002; Overmars et al. in Ecol Model 164:257–270, 2003; Brown and Spector in J Appl Ecol 45:1639–1648, 2008; Koniak and Noy-Meir in Ecol Model 220:1148–1158, 2008). These problems are inherently multivariate, though researchers commonly rely on univariate methods, such as spatial regression models, to address them. In this paper, we introduce a multivariate method—graphical spatial models—that extends path analysis to incorporate spatial autocorrelation in one or more variables in a directed graph. We show how both exogenous and endogenous ecological processes as defined by Legendre et al. (Ecography 25:601–615, 2002) and Lichstein et al. (Ecol Monographs 72:445–463, 2002) can be represented in a graph. Most importantly, we show how to translate graphs representing these ecological processes into statistically estimable models. We motivate our theoretical results using an example of stream health data from the Willamette Valley, Oregon. For these data we are interested in the spatial pattern within both riparian land use and an index of stream health, and whether there is an association between land use and stream health, after accounting for these spatial patterns. We use a graphical spatial model to address these ecological questions simultaneously. We find that the health of a stream decreases as the percent of developed land within a 120-m riparian buffer increases; interestingly, there is only evidence of spatial pattern within land use.     

Characterization of hard- and softwood biochars pyrolyzed at high temperature

A wide range of waste biomass/waste wood feedstocks abundantly available at mine sites provide the opportunity to produce biochars for cost-effective improvement of mine tailings and contaminated land at metal mines. In the present study, soft- and hardwood biochars derived from pine and jarrah woods at high temperature (700 °C) were characterized for their physiochemical properties including chemical components, electrical conductivity, pH, zeta potential, cation-exchange capacity (CEC), alkalinity, BET surface area and surface morphology. Evaluating and comparing these characteristics with available data from the literature have affirmed the strong dictation of precursor type on the physiochemical properties of the biochars. The pine and jarrah wood feedstocks are mainly different in their proportions of cellulose, hemicellulose and lignin, resulting in biochars with heterogeneous physiochemical properties. The hardwood jarrah biochar exhibits much higher microporosity, alkalinity and electrostatic capacity than the softwood pine. Correlation analysis and principal component analysis also show a good correlation between CEC–BET–alkalinity, and alkalinity–ash content. These comprehensive characterization and analysis results on biochars’ properties from feedstocks of hardwood (from forest land clearance at mine construction) and waste pine wood (from mining operations) will provide a good guide for tailoring biochar functionalities for remediating metal mine tailings. The relatively inert high-temperature biochars can be stored for a long term at mine closure after decades of operations.     

Effects of light exposure on the retention of kleptoplastic photosynthetic activity in the sacoglossan mollusc <Emphasis Type="Italic">Elysia viridis</Emphasis>

The effects of light exposure on the photosynthetic activity of kleptoplasts were studied in the sacoglossan mollusc Elysia viridis. The photosynthetic activity of ingested chloroplasts was assessed in vivo by non-destructively measuring photophysiological parameters using pulse amplitude modulation (PAM) fluorometry. Animals kept under starvation were exposed to two contrasting light conditions, 30 μmol photons m⁻² s⁻¹ (low light, LL), and 140 μmol photons m⁻² s⁻¹ (high light, HL), and changes in photosynthetic activity were monitored by measuring the maximum quantum yield of photosystem II (PSII), F _v/F _m, the minimum fluorescence, F _o, related to chlorophyll a content, and by measuring rapid light-response curves (RLC) of relative electron transport rate (rETR). RLCs were characterised by the initial slope of the curve, α_RLC, related to efficiency of light capture, and the maximum rETR level, rETR_m,RLC, determined by the carbon-fixation metabolism. Starvation induced the decrease of all photophysiological parameters. However, the retention of photosynthetic activity (number of days for F _v/F _m > 0), as well as the rate and the patterns of its decrease over time, varied markedly with light exposure. Under HL conditions, a rapid, exponential decrease was observed for F _v/F _m, α_RLC and rETR_m,RLC, F _o not showing any consistent trend of variation, and retention times ranged between 6 and 15 days. These results suggested that the retention of chloroplast functionality is limited by photoinactivation of PSII reaction center protein D1. In contrast, under LL conditions, a slower decrease in all parameters was found, with retention times varying from 15 to 57 days. F _v/F _m, α_RLC and rETR_m,RLC exhibited a bi-phasic pattern composed by a long phase of slow decrease in values followed by a rapid decline, whilst F _o decayed exponentially. These results were interpreted as resulting from lower rates of D1 photoinactivation under low light and from the gradual decrease in carbon provided by photosynthesis due to reduction of functional photosynthetic units.     

Teil III: Stoffstromanalyse

A material flow analysis is performed to check the measures of groundwater protection, especially those undertaken to reduce nitrate leaching in water protecting areas. The impacts both of direct and of indirect agricultural processes are assessed. Implementing the methodology of cost counting into the material flow analysis allows one to test whether the equalization payments (agreed on in voluntary agreements between farmers and water economy for special groundwater protecting measures as direct drilling or intercropping) are appropriate for compensating the resulting economical losses for the farmer. It is shown that this extensive production produces more profit — despite lower yields and inferior quality — due to equalization and lower production costs. However, these results strongly depend on yield estimation. Groundwater protecting measures with low input (e.g. nitrogen reduction) reduce environmental impacts on a regional and also on a global scale, while other measures such as intercropping increase them due to additional fertilizer application. So it is still difficult to choose one or the other because of weighing global against regional effects in a qualitative and quantitative way.     

Teil V: Bewertung landwirtschaftlich-industrieller Stoffströme

Agricultural and industrial production chains as product lines are connected and their assessment is performed for a varnish based on linseed oil that is almost completely composed of renewable raw materials. Using a production line analysis, the ecological and social effects of the production are assessed, and different assessment techniques for ecological assessment are used as well. The life cycle inventory results from a material flow analysis including pre-production chains. For optimisation, a scenario of conventional agricultural linseed oil production against ecologically produced linseed oil is assessed. All assessment methods identify the same aspect of the product as the most important: The content of volatile organic compounds (VOC), that are released during usage. Further problems such as waste in the oil mill, emittance of acidic substances (mostly NO_x) from burning and heavy metals from tinplate production for containers are identified only from one or another of the assessment methods, a feature which stresses the influence on results from the choice of method. All methods prefer the ecological production of linseed, but the significance regarding the system boundaries is low (0.6% UBP, 1.7% Eco-indicator) due to dominating VOC-emissions. The use of material flow analyses in LCA is possible for agricultural production, especially seamless connection is provided between the different production steps. Also parameterisation is easy so that the defining of scenarios is efficient and transparent.     

Seasonal variation and social correlates of androgen excretion in male redfronted lemurs (Eulemur fulvus rufus)

The aim of this study was to examine effects of seasonal and social factors on male androgen excretion in a seasonally breeding primate living in multimale-multifemale groups. By combining detailed behavioural observations (>2,500 h) on 3 groups of redfronted lemurs living in Kirindy Forest/Madagascar with non-invasive hormone analysis of >800 faecal samples collected concomitantly from the same animals, we tested predictions on: (1) the effect of social status on immunoreactive testosterone (iT) excretion; (2) seasonal variation of iT across reproductive periods; and (3) the relationship between aggression and iT excretion. The study lasted 14 months, covering two mating and one birth season. The results revealed that males fall into two distinct social classes, with one dominant male and several subordinate males in each group. In contrast to our prediction, the behavioural differences between these two classes were not reflected by differences in androgen levels, making physiological suppression of testicular function an unlikely mechanism of male reproductive competition. As expected for a seasonally breeding animal, iT values were elevated during the mating season. Androgen levels tracked the increase in the rate of reproductive aggression during the mating season as predicted by the challenge hypothesis. An increase in aggression due to spontaneous social instability outside the mating season, however, was not linked to a parallel rise of iT. Furthermore, the highest iT levels were obtained during the birth season, which may be part of a male strategy to remain aggressive during this period of high infanticide risk. These findings suggest that redfronted lemurs do not respond with increases in androgens to short-term challenges and that high androgen levels instead correlate with longer-lasting and predictable situations, such as the mating and birth seasons.     

Passive sampler derived air concentrations of PBDEs along an urban-rural transect: spatial and temporal trends

Passive air samplers consisting of polyurethane foam (PUF) disks housed in chambers were deployed at several sites along a approximately 75 km urban-rural gradient in Toronto and analyzed for polybrominated diphenyl ethers (PBDEs). Samplers were allowed to integrate gas-phase PBDEs over three consecutive seasons starting in the summer of 2000. PBDEs were fairly uniform along the transect with air concentrations in Toronto (10-30 pgm(-3)) about a factor of two greater than at rural sites. Lowest concentrations were observed during the winter and probably associated with reduced inputs from indoor sources of PBDEs and to a preference for PBDEs to partition to the particle-phase at colder temperatures. The composition of PBDEs in the air samples did not differ across the transect or for the different seasons.     

Sediment pollution and dynamic in the Mar Piccolo of Taranto (southern Italy): insights from bottom sediment traps and surficial sediments

Major and trace element, PAH, and PCB concentrations were measured in surface sediments and particles from sediment traps collected in the First and Second Basin of the Mar Piccolo (Gulf of Taranto) in two periods (June–July and August–September, 2013). The aim of the study was to evaluate pollution degree, sediment transport and particle redistribution dynamic within the area. Results confirm the higher contamination of sediments from the First Basin observed by previous researches, particularly for Cu, Hg, Pb, total PAHs, and total PCBs. Advective transport from the First to the Second Basin appears to be the leading transfer mechanism of particles and adsorbed contaminants, as evidenced by measured fluxes and statistical analyses of contaminant concentrations in surficial sediments and particles from sediment traps. Long-range selective transports of PAHs and microbial anaerobic degradation processes for PCBs have been also observed. These results are limited to a restricted time window but are consistent with the presence of transport fluxes at the bottom of the water column. This mechanism deserves further investigation and monitoring activities, potentially being the main responsible of pollutant delivering to the less contaminated sectors of the Mar Piccolo.     

Ecosystem responses to climate change at a Low Arctic and a High Arctic long-term research site

Long-term measurements of ecological effects of warming are often not statistically significant because of annual variability or signal noise. These are reduced in indicators that filter or reduce the noise around the signal and allow effects of climate warming to emerge. In this way, certain indicators act as medium pass filters integrating the signal over years-to-decades. In the Alaskan Arctic, the 25-year record of warming of air temperature revealed no significant trend, yet environmental and ecological changes prove that warming is affecting the ecosystem. The useful indicators are deep permafrost temperatures, vegetation and shrub biomass, satellite measures of canopy reflectance (NDVI), and chemical measures of soil weathering. In contrast, the 18-year record in the Greenland Arctic revealed an extremely high summer air-warming of 1.3 °C/decade; the cover of some plant species increased while the cover of others decreased. Useful indicators of change are NDVI and the active layer thickness.