Territory and group sizes in Eurasian beavers (Castor fiber): echoes of settlement and reproduction?

According to current theories of territoriality, an animal is expected to defend the smallest area that can provide resources for maximisation of reproduction, known as the economically defendable area. In group territorial species however, the strategies behind resource defence are likely to be more complex with corporate territoriality, cooperative breeding, delayed dispersal and intra-group competition all potentially playing a role. Here we examined group territoriality in a social herbivorous rodent, the Eurasian beaver Castor fiber. Beavers in our study do not inhabit economically defendable territories. Instead the sequence of arrival of pairs into unoccupied areas seems to play a more important role in determining the size of the territory, whereas group size is determined by past reproductive success. We argue that the settlement pattern and reproductive history have a lasting impact in the territorial system of beavers due to a combination of the low adult mortality, high dispersal costs, and avoidance of resource depletion.R.D. Campbell and F. Rosell contributed equally to this work     

Competitive interactions between related clades: evolutionary implications of overgrowth interactions between encrustin cyclostome and cheilostome bryozoans

Overgrowth interactions between encrusting cyclostome (eight species) and cheilostome (over 50 species) colonies were examined in subtidal communities in the northern Adriatic Sea off Rovinj, Croatia, in May–June 1988 and September–October 1990. Cheilostome colonies occupied ca. 80% of the available substrate space, whereas the cyclostome colonies occupied <5%. Out of 210 recorded interactions, cheilostomes overlapped cyclostomes in 164, while cyclostomes overlapped cheilostomes in only 16; 30 encounters resulted in mutual overlap or at least temporary growth termination along the line of contact. Most of the recorded interactions were for the cyclostomes Diplosolen obelia (Johnston) and Plagioecia patina (Lamarck). Both species elevated their colony margins on contact with a cheilostome in some instances, but D. obelia only overgrew competing cheilostomes in 12/120 encounters, and P. patina never prevailed. I propose that the cheilostomes have a key evolutionary innovation, lacking in cyclostomes, consisting of more rapid ontogenetic development of zooids along colony margins so that encrusting cheilostomes have substantially higher colony margins. This results in an outflow of filtered water along the edge of encrusting cheilostome colonies, while cyclostomes take water in at colony margins. These contrasting feeding currents apparently give a competitive advantage to the cheilostomes where colony margins approach and make contact with those of cyclostomes.     

The Journal of Coastal Conservation, 1995–2004

This paper concludes the publication of theJournal of Coastal Conservation from 1995–2004 after the European Coastal Union and the Publishers decided to terminate the production of the journal. We look back at the 206 research papers published in this period while concentrating on Geographical and ecological variation, Focuses and trends, and Progress in European coastal conservation and management. Three indices are added: (1) a list of the 206 papers; (2) an Author Index; and (3) a Subject Index based on the titles, keywords and some additional important subjects found in the tables and figures.     

A new approach to quantifying and comparing vulnerability to drought

In this study we develop an “inference modeling” approach to compare and analyze how different disciplines (economics, political science, and behavioral science/environmental psychology) estimate vulnerability to drought. It is thought that a better understanding of these differences can lead to a synthesis of insights from the different disciplines and eventually to more comprehensive assessments of vulnerability. The new methodology consists of (1) developing inference models whose variables and assertions incorporate qualitative knowledge about vulnerability, (2) converting qualitative model variables into quantitative indicators by using fuzzy set theory, (3) collecting data on the values of the indicators from case study regions, (4) inputting the regional data to the models and computing quantitative values for susceptibility. The methodology was applied to three case study regions (in India, Portugal and Russia) having a range of socio-economic and water stress conditions. In some cases the estimates of susceptibility were surprisingly similar, in others not, depending on the factors included in the disciplinary models and their relative weights. A new approach was also taken to testing vulnerability parameters by comparing estimated water stress against a data set of drought occurrences based on media analysis. The new methodologies developed in this paper provide a consistent basis for comparing differences between disciplinary perspectives, and for identifying the importance of the differences.

Who is susceptible and why? An agent-based approach to assessing vulnerability to drought

In this paper, we specify susceptibility to drought from a psychology-based bottom-up perspective. On the basis of the protection motivation theory (Rippetoe and Rogers in J Pers Soc Psychol 52(3):596–604, 1987), we developed the protection-capacity model (Krömker and Mosler in Global environmental change in Alpine regions: impact, recognition, adaptation, and mitigation. Edward Elgar, Cheltenham, pp 93–112, 2002) to analyse the susceptibility with respect to the protection capacity of agents. The protection capacity is determined by the agents’ subjective assessment of the situation, which consists of the appraisal of threat, on the one hand, and the coping appraisal, on the other hand. Additionally, the protection-capacity model specifies several factors which influence the two central appraisal processes. Empirical data were collected in interviews with experts and with a total of 65 exemplarily selected households which are typical for the respective case study regions (Andhra Pradesh, India; Algarve and Alentejo, Portugal; Volgograd and Saratov, Russia). The data were analysed with the help of fuzzy set methodology. Results show that the households of the Indian region are the most susceptible when compared to those of the Russian region with ‘low’ and to households of the Portuguese region with a ‘very low’ degree of susceptibility. Moreover, we identified subgroups within the regions which are characterized by different degrees of susceptibility and a different profile of factors influencing susceptibility. Altogether, the agent-based perspective allows identifying relevant factors that need to be addressed to minimize susceptibility of the population and special subgroups. However, the results are not representative for the case study regions because of the small database. Additionally, more effort is needed to validate the findings.     

Electrochemical removal of metal ions from aqueous solution: a student workshop

An environmental electrochemistry workshop program on metal ion removal is described. The program was designed for undergraduate students in chemistry, chemical engineering or environmental science and teaches environmental electrochemistry through a combination of hands-on experiments, understanding of research concepts, completion of project reports and in class discussion. The students are encouraged to quantitatively describe the performance of the electrochemical cells (containing 2-D and 3-D carbon cathodes) and to consider the advantages and shortcomings of electrochemical routes to environmental treatment.     

HYDROLOGIC RESPONSE TO PUMPING AND CONTAMINANT ADVECTION IN A FRACTURED ROCK ENVIRONMENT1

ABSTRACT: Ground water flow and supply at the Whiteshell Research Area (WRA) in southeastern Manitoba and the advective movement of contaminants from a hypothetical nuclear fuel waste disposal vault to the adjacent biosphere and a nearby ground water supply well are simulated using finite-element modeling and numerical particle-tracking technique. The hypothetical vault is located at a depth of 500 m, below the water table, in low-permeability plutonic rock of the Canadian Shield. The rock mass is intersected by high-permeability fracture zones (aquifers), which also act as conduits for vault contaminants to migrate to the ground surface. The ground water resource is, therefore, limited in quantity and quality and should be explored with care. A 30 m deep well, which pumps water at a rate of 120 m³/yr from a low-dipping fracture zone, LD1, reduces natural discharge from the system to augment natural recharge. At this pumping rate, a 100 m or 200 m deep well neither reduces discharge nor induces recharge into the system. Thus, at the WRA, a 30 m deep domestic water supply well best meets the water requirements of a one-person household at the rate of 120 m³/yr. The 100 m and 200 m wells best meet the requirements of a family of six and a family of six with light irrigation, respectively, without capturing contaminants’pathways from the vault to the ground surface. By virtue of the proximity of the 200 m well intake to the hypothetical vault, this well performs best as a purge well at pumping rates of 0,000 m³/yr and greater. Finite-element modeling is useful in evaluating the water supply potential of a fractured rock environment in which a nuclear waste disposal vault is proposed to be sited.     

Air-mediated pollen flow from genetically modified to conventional crops.

Tools for estimating pollen dispersal and the resulting gene flow are necessary to assess the risk of gene flow from genetically modified (GM) to conventional fields, and to quantify the effectiveness of measures that may prevent such gene flow. A mechanistic simulation model is presented and used to simulate pollen dispersal by wind in different agricultural scenarios over realistic pollination periods. The relative importance of landscape-related variables such as isolation distance, topography, spatial configuration of the fields, GM field size and barrier, and environmental variation are examined in order to find ways to minimize gene flow and to detect possible risk factors. The simulations demonstrated a large variation in pollen dispersal and in the predicted amount of contamination between different pollination periods. This was largely due to variation in vertical wind. As this variation in wind conditions is difficult to control through management measures, it should be carefully considered when estimating the risk of gene flow from GM crops. On average, the predicted level of gene flow decreased with increasing isolation distance and with increasing depth of the conventional field, and increased with increasing GM field size. Therefore, at a national scale and over the long term these landscape properties should be accounted for when setting regulations for controlling gene flow. However, at the level of an individual field the level of gene flow may be dominated by uncontrollable variation. Due to the sensitivity of pollen dispersal to the wind, we conclude that gene flow cannot be summarized only by the mean contamination; information about the frequency of extreme events should also be considered. The modeling approach described in this paper offers a way to predict and compare pollen dispersal and gene flow in varying environmental conditions, and to assess the effectiveness of different management measures.     

Flächenauswahl und Ökosystemares Monitoring in den Biosphärenreservaten Schorfheide-Chorin und Spreewald

For the two biosphere-reserves of Schorfheide-Chorin and Spreewald in the Federal State of Brandenburg, Germany, we designed a concept for a monitoring program of ecosystems which is feasible and inexpensive, and whose methodical development is transferable to other large-scale protected areas. Beside the statistical analysis of hard GIS data, we systematically used additional criteria such as naturalness, scarcity and special management, a based on expert knowledge. Thus, after an inventory of the existing ecosystems, we selected the ecosystems to be monitored from the different ecosystem groups (i.e. woods and forests, fens, lakes, rivers, arable land and grasslands) based on the following four criteria:

1. dominance,
2. naturalness,
3. nation-wide scarcity and
4. special management.

We then combined the selected ecosystems with their relevant forms of landuse to so-called ecosystem-landuse-complexes, which reflect the natural conditions as well as the human impact in the biosphere reserves. This paper presents the selection of the ecosystem landuse complexes to be monitored. Thus, for both biosphere reserves, we obtained 32 ecosystem landuse complexes in woods and forests, 32 in fens, 53 in lakes, 7 in rivers, 23 in grasslands and 20 in arable land.     

Polyphenols and their influence on gut function and health in ruminants: a review

Polyphenols in plants can protect proteins from degradation and improve the efficiency of conversion of plant protein to animal protein (meat and milk), but can this be achieved in a way that is environmentally sustainable, profitable to the livestock farmer and is consistent with aspirations for improved livestock nutrition, health, welfare and product quality? Given that grazed and conserved forage is the bedrock of sustainable ruminant production, this paper attempts to consider what challenges are ahead in terms of enhancing productive efficiency, reducing the polluting footprint of livestock agriculture and alleviating the endemic parasitism that occurs with grazing animals.