The value of time in recreation benefit studies

This paper examines the role of time costs—both on-site and travel—in models describing recreation behavior, and draws implications for the travel-cost approach to recreation site benefit estimation. The analysis shows that both recreation and travel time are costly. The latter can be valued in terms of its scarcity value, but the former may be most appropriately valued in terms of the “alue of travel time saved.” Although there are cases in which on-site time costs need not be explicitly considered in recreation benefit models, it is not clear such cases are the rule rather than the exception. Suggestions are made for measuring on-site and travel time costs.     

Bewertungsmaßstäbe für die biologische Vielfalt

The main objective of the UN Convention on Biological Diversity is the global conservation of biological diversity. As biological diversity is utilised — directly or indirectly — as a resource for human needs, this utilisation has to be made sustainable. The elaboration of adequate protection and utilisation concepts requires suitable evaluation criteria to measure sustainability. For the sector of environmental protection, the Federal Environmental Agency has carried out a study to determine the criteria which are currently used in different areas. This study (review and evaluation) covers not only the criteria themselves, but also includes additional information such as the underlying principles. Biodiversity as an autonornous area of protection has been addressed in only quite a few papers up to now. However, there already exists a range of criteria which are relevant for biodiversity. But at the same time many gaps’ and inconsistencies were identified which have to be eliminated in cooperation with other policy sectors to obtain a basis for the above-mentioned protection and utilisation concepts.     

镉胁迫下蚯蚓金属硫蛋白氧化修饰的研究(Oxidative Modification of Metallothionein in Earthworm under Cd Stress)

金属硫蛋白(MT)是生物体内的一类富含巯基(—SH)的蛋白,在细胞氧化还原调控和重金属解毒等方面具有重要作用.MT的—SH可以络合重金属,同时对氧化作用很敏感,重金属胁迫产生的活性氧物质(ROS)可以将其氧化成二硫键(S—S).为揭示镉(Cd)对蚯蚓MT的—SH含量及其氧化修饰的影响,将蚯蚓放入Cd浓度为0、100、300mg·kg-1的黄棕壤中胁迫21天,通过SBD-F标记和高效液相色谱(HPLC)结合的方法测定MT中—SH和S—S的含量.结果显示,随着Cd浓度的增加,蚯蚓体内的—SH和S—S含量均逐渐增加,但S—S所占比例降低.这说明Cd诱导了蚯蚓体内MT合成,并且诱导量随着Cd胁迫的增强而增加,但—SH的氧化修饰程度有所下降.     

Langfristigkeit ökosystemarer Forschung

Time in environmental science continues to be almost neglected. In connection with rising ecological problems long-term research, as is necessary for the evaluation and prediction of environmental conditions, seems to be an exception. Complex ecosystems, e.g. terrestrial and marine systems, however, are characterized by long lasting natural time-scales which must be taken into account by analyzing them. In this context the role of time in ecosystems research becomes important. Therefore, a data base was conceptualized that could take up the main characteristics of ecosystematic analyses. Annual research reports of ecosystem research centers were revised for taking them up into the data base. In this way it is possible to evaluate the pool of data on special aspects, especially on the time parameters of the analyses. One result — besides a partial unequality of the time scales in experiment and reality — is that long-term research in terrestrial ecosystems is very rare. The reasons for this are various, but cannot divert from the need for a greater consideration of longterm observation of the ecosystems. Otherwise the ecosystematic research will not be able to meet their tasks of evaluation and prediction.     

Is it only the regulatory status? Broadening the debate on cisgenic plants

In current debates on emerging technologies for plant breeding in Europe, much attention has been given to the regulatory status of these techniques and their public acceptance. At present, both genetically modified plants with cisgenic approaches—using genes from crossable species—as well as transgenic approaches—using genes from different species—fall under GMO regulation in the EU and both are mandatorily labelled as GMOs. Researchers involved in the early development of cisgenic GM plants convey the message that the potential use and acceptance of cisgenic approaches will be seriously hindered if GMO regulations are not adjusted. Although the similar treatment and labelling of transgenic and cisgenic plants may be a legitimate concern for the marketability of a cisgenic GM plant, there are concerns around their commercialization that reach beyond the current focus on (de)regulation. In this paper, we will use the development of the cisgenic GM potato that aims to overcome ‘late blight’—the most devastating potato disease worldwide—as a case to argue that it is important to recognize, reflect and respond to broader concerns than the dominant focus on the regulatory ‘burden’ and consumer acceptance. Based on insights we gained from discussing this case with diverse stakeholders within the agricultural sector and potato production in Norway during a series of workshops, we elaborate on additional issues such as the (technical) solution offered; different understandings of the late blight problem; the durability of the potato plant resistance; and patenting and ownership. Hence, this paper contributes to empirical knowledge on stakeholder perspectives on emerging plant breeding technologies, underscoring the importance to broaden the scope of the debate on the opportunities and challenges of agricultural biotechnologies, such as cisgenic GM plants. The paper offers policy-relevant input to ongoing efforts to broaden the scope of risk assessments of agricultural biotechnologies. We aim to contribute to the recognition of the complex socio-ecological, legal and political dimensions in which these technological developments are entangled as a means to acknowledge, discuss and respond to these concerns and thereby contribute to more comprehensive and responsible developments within agricultural biotechnology.     

Quelques données sur le déterminisme ecologique de la reproduction des annélides polychètes

The geographical distribution of marine invertebrate species — Annelida Polychaeta in the present case — is not random. It permits the definition of partially overlapping biogeographical groups. These groups are disposed in a line corresponding to a north-south axis. The seasonal cycles of occurrence of pelagic larvae are considered in southern Scandinavia (on the basis of literature sources), in the western Mediterranean Sea, and in the Indian Ocean (both on the basis of own data). The criterium of reproduction is the presence of meroplanktonic larvae of benthonic species. In this way, it has been possible to distinguish stocks of boreal, temperate and sub-tropical affinity. Within a given stock, the breeding season depends on the site of observation and on ecological factors. The breeding season is retarded for 6 months in southarn Scandinavia as compared to the western Mediterranean Sea, although these species belong to the same stock. This type of comparative study allows emphasis of the role of certain ecological factors related to reproduction (temperature, abundance of phytoplankton, etc.). Breeding may be triggered by different ecological factors, even in animals belonging to one and the same geographical stock: in the Mediterranean Sea, the breeding of the so-called subtropical species seems to be controlled by temperature (monthly variations); in the Indian Ocean, by high levels of phytoplankton abundance. A comparison of temperate species with those of southern Scandinavia and the Mediterranean Sea reveals differences in breeding seasons, which are correlated with thermal regime; breeding does not occur below or above a specific temperature, but is restricted to an optimum value, which appears to be a physiological species characteristic.     

Challenge, dialogue, action… Recent developments in the protection of coastal zones in Italy

In Italy, the incapability of the State to implement a national strategy for the sustainable development of coastal areas lead the regional authorities to adopt integrated coastal zone management plans. These initiatives are often relevant, correcting the defiency of the national legislation, but do not assure the implementation of a coherent littoral policy. Thereby, it is to be hoped that the recent developments in international law—and particularly the Mediterranean protocol on integrated coastal zone management recently adopted—will compel the Italian State to make a positive commitment to coastal protection.     

Defining and achieving sustainable development

SUMMARY

This paper analyses the fundamental problems of defining and achieving sustainable development. A common core of the various definitions of sustainability circulating is identified. Economic and scientific approaches to operationalize sustainability generally lead to management rules, which — if obeyed — should guarantee sustainability. Since it is not possible to precisely predict the future, this scientific—technical—economic route to sustainability may fail. A second, ethical way, to sustainability which interprets sustainability as an ideal for fair play is introduced. How the two different ways may complement one another with a three-step hierarchy of political goals is elucidated.     

Should consumptive sustainable use of Sika Deer (Ceruus nippon) in Dilijan Reserve,NE Armenia be instituted?

SUMMARY

Numbers of sika deer (Ceruus nippon), resident in the Dilijan Reserve in 1969 (52 animals), 1970 (50), 1972 (1), and 1976 (28) dramatically increased in number until 1981, when the population reached a ceiling, being the number which can subsist in the area—300 individuals (density—11–12.5 deer per 1000 ha). Thus, Dilijan Reserve's C. nippon population develops in a way which resembles an S-like log curve equation.

Actually, Dilijan Reserve no longer has the status of a protected area—nowadays lumbering activities predominate and, inevitably, the unique broadleaf deciduous forest ecosystem will run down to extinction. Such economically valuable species as oak, beech, and sika deer are likely to be the first victims of this large-scale devastation.

The present article does not reject exploitation of any resource (including sika deer), if necessary. The key question is: how C. nippon can be sustainably utilized, so that the number of culled animals is replenished within the same year and and so that eventually the population size will remain constant?     

Das Biologische System der Elemente (BSE): Eine modelltheoretische Betrachtung zur Essentialität von chemischen Elementen

The correlation of data on the elements obtained by instrumental chemical analysis of highly representative plant samples led to the establishment of a first Biological System of Elements (BSE) in 1994. Including other physiological parameters like availability of chemical elements, transport, storage, etc. it is clear, that aside from the bioinorganic aspects of coordination chemistries of given elements, features of essentiality or toxicity depend on their interference with enzymatic processes. Notably, the latter are not to be considered as purely catalytic transformations, but are instead related to the reproduction of organisms in a direct or indirect manner — as autocatalytic: a process whereby a protein containing some metal or burdened in function by its presence is indirectly involved in its own reproduction. Stoichiometric Network Analysis (SNA) explicitly deals with the general dynamics of such autocatalytic systems. Given there is a relationship between the kinds of metal or metalloid species and the key biological/biochemical transformations to be promoted using them — a relationship which is the topic of bioinorgnaic chemistry-, and that biochemistry is in effect about systems which can reproduce and thus behave autocatalytically, one can expect SNA to yield statements on the basic features of biology and biochemistry as well.     

Die Rolle von Kommunikation in der Umweltbewertung

Goal and Scope

Planning projects concerning the environment often provoke problems due to a lack of transparency of the applied scales and the appropriate evaluation methods. This paper therefore examines the general structure of all valuation processes before describing the character of the economic evaluation method in detail. From this point of view, requirements on planning processes are coming out which are to be achieved if their duty — the provision of public goods — is to be carried out efficiently.

Features

It will be shown that from an economist’s perspective a planning procedure acts as a surrogate of the market in coordinating individual’s preferences. The reasons for the inefficient level of the provision of environmental goods by private producers are their main characteristics: non-rivality and non-excludability; therefore public goods do not possess prices. Thus environmental goods have to be produced by cooperation and planning processes have to guarantee this. The main character of planning procedures is be seen in communication processes which is documented by a narrative study.

Results and Conclusions

Planning projects concerning the environment are strongly contingent on communication processes. Thus, they are also controllable by communication. The interdisciplinary research in communications shows that cooperative behaviour which is required for planning projects that should provide public goods can be benefited by applicative communication technologies. In this juncture (social) norms more and more emerge to act an important part in conveying cooperative behaviour. Especially so called ‘Sozialtechniken’ seem to be able to activate such norms.

Outlook

From the economist’s point of view planning projects concerning the environment mostly desiderate two things: Firstly, the procedures and methods which are applied to evaluate the regarding environmental goods in many cases suffer from transparency. Secondly, individual’s preferences predominant by the local population and accordingly by the directly involved parties are mostly not acquired adequately to achieve an efficient allocation of environmental goods. Applying more communication technologies to solve these two problems in the future both an increase of efficiency and an increase of the acceptability of such planning projects can be expected.     

A geological perspective on the degradation and conservation of western Atlantic coral reefs

Continuing coral‐reef degradation in the western Atlantic is resulting in loss of ecological and geologic functions of reefs. With the goal of assisting resource managers and stewards of reefs in setting and measuring progress toward realistic goals for coral‐reef conservation and restoration, we examined reef degradation in this region from a geological perspective. The importance of ecosystem services provided by coral reefs—as breakwaters that dissipate wave energy and protect shorelines and as providers of habitat for innumerable species—cannot be overstated. However, the few coral species responsible for reef building in the western Atlantic during the last approximately 1.5 million years are not thriving in the 21st century. These species are highly sensitive to abrupt temperature extremes, prone to disease infection, and have low sexual reproductive potential. Their vulnerability and the low functional redundancy of branching corals have led to the low resilience of western Atlantic reef ecosystems. The decrease in live coral cover over the last 50 years highlights the need for study of relict (senescent) reefs, which, from the perspective of coastline protection and habitat structure, may be just as important to conserve as the living coral veneer. Research is needed to characterize the geological processes of bioerosion, reef cementation, and sediment transport as they relate to modern‐day changes in reef elevation. For example, although parrotfish remove nuisance macroalgae, possibly promoting coral recruitment, they will not save Atlantic reefs from geological degradation. In fact, these fish are quickly nibbling away significant quantities of Holocene reef framework. The question of how different biota covering dead reefs affect framework resistance to biological and physical erosion needs to be addressed. Monitoring and managing reefs with respect to physical resilience, in addition to ecological resilience, could optimize the expenditure of resources in conserving Atlantic reefs and the services they provide.     

Analysis of particulates by Raman microprobe†

We describe a new technique of local analysis of heterogeneous samples which is analogous to the electron or ion microprobe but is based on molecular spectra of materials to characterize the different components of a microscopic sample and (or) to obtain images giving their surface distribution.

The sample is illuminated by a laser beam causing characteristic Raman lines of the different components to be emitted. Using these Raman lines, the components can then be detected, identified and located. For this purpose, the microscopic area of the preparation which is illuminated is analysed by a conventional optical microscope coupled with a tunable band pass filter and a multichannel or monochannel detection system.

One main advantage of this technique is the ability to study samples not under vacuum but in air, under a controlled atmosphere or even inside a transparent matrix. Normal Raman spectra can be obtained from particles of 1 μm size and larger, and are the basis for the qualitative identification of molecular constituents. The technique has been applied to molecular microanalysis of matter in the particulate form (i.e., Airborne particles—stack particulates, flyash, asbestos minerals, defects and inclusions in industrial materials,...). It is especially interesting for organic materials which are not detected by other methods. Different examples illustrate this technique.     

Teil II: Stoffstromnetze für Fruchtfolgen

The general results of material flow analyses for agricultural farms presented in Part I are now specified for three farms in Lower Saxony. For this, the existing material flow net for winter wheat is extended by the crops of winter barley, winter rye, summer barley, rape, sugar beets and potatoes. The assessment is essentially done regarding the impact categories of resource depletion, cumulated energy demand (CED) and emissions to atmosphere. Besides the assessment of single farms or crops, also the comparison, of different agricultural production systems is possible, whereby the choice of the functional unit and the basis of comparison (with reference to input or output) is of major importance. Additionally, as for agricultural means of production, the material flows and emissions resulting from the provision of carbolime — an often employed carbonate fertiliser as for sugar-beet cultivation — are derived completely within this article. Furthermore, sensitivity analyses on the subject of detail intensity of agricultural basic data are presented for the example of machine employment. The material flow nets are regarded as transferable to other farms with similar crop rotation systems, with an appropriate expenditure of information gathering and parameterisation. The complete net can be used as a module within further investigations, e.g. of the industrial processing of food, as a pre-production chain for agricultural resources being part of the production process (winter wheat — mill, brewing barley — brewery, sugar beets — sugar-factory).     

“Armpit effect” in an African cichlid fish: self-referent kin recognition in mating decisions of male Pelvicachromis taeniatus

Kin discrimination in nepotistic as well as in sexual contexts is widespread in animals including humans. However, the underlying mechanisms of kin discrimination are assumed to vary between species and—within species—between contexts. During solitary life stages, kin recognition based on social learning is assumed to be less reliable because kin templates that are not continuously updated may get lost. Therefore, self-referent phenotype matching (“armpit effect”), i.e., the comparison of unknown phenotypes with own characteristics, should be particularly relevant when no social cues are available. However, experimental evidence for this mechanism is scarce. Here, we examine self-referent kin recognition in a mate-choice context in adult male Pelvicachromis taeniatus, a socially monogamous cichlid fish from West Africa with biparental brood care and pronounced kin-mating preferences. Juvenile P. taeniatus live in groups, whereas adult males compete for access to breeding sites which they aggressively defend against rivals. Using computer-animated females as standardized visual stimuli in combination with olfactory cues of related and unrelated females, we show that adult males reared isolated from kin since egg stage were able to discriminate sisters from unrelated females. As males could have learned kin cues only from themselves, our study provides evidence for self-referent kin recognition and indicates that the observed inbreeding preferences are mediated by self-derived olfactory cues. Male preferences for sisters were correlated with male body size. We discuss the implications of quality-related mate choice for the evolution of kin-mating preferences.     

Cost sharing to induce efficient techniques of abating wastewater pollution

This paper analyzes existing cost-sharing rules for wastewater pollution grants administered by the Environmental Protection Agency under the 1972 Amendments to the Federal Water Pollution Control Act. It identifies and measures biases in the existing cost-sharing rules that encourage nonfederal interests to select particular techniques (e.g., capital-intensive techniques) over others even when the selected techniques are not the least costly to the nation. The paper develops theoretically a cost-sharing condition—that the same percentage cost share be applied to all abatement techniques—that would eliminate the cost-sharing bias. Alternative cost-sharing approaches are evaluated in terms of their biasing effects and their absolute dollar costs for federal and nonfederal project participants.     

Distribution,fate and persistence of organochlorine compounds formed during production of bleached pulp

The processes governing distribution of a xenobiotic compound discharged initially into the environment are discussed, and attention is drawn to (a) binding to organic matter in the sediment phase which affects both persistence and toxicity to biota and (b) the role of atmospheric transport for compounds of low water solubility and high vapour pressure. Important limitations in the use of sum parameters such as EOCI are pointed out. The important distinction between biodegradation and biotransformation is pointed out, and significant experimental determinants noted. Pathways for the aerobic metabolism of chlorophenolic compounds are discussed, and attention is drawn to the role of O‐methylation as an environmentally significant alternative to biodegradation. Evidence for the biodegradation of chlorinated aliphatic acids and hydrocarbons under both aerobic and anaerobic conditions is presented. Anaerobic metabolism of chlorophenolic compounds is discussed with respect to (a) de‐O‐methylation of chloroguaiacols, (b) dechlorination of chlorocatechols and (c) reduction of chlorovanillins. It is emphasized that current evidence provides a complex metabolic picture, and that only partial dechlorination may occur. Brief attention is given to the important issue of the persistence of chlorolignin, and attention drawn to technical issues which render this problem difficult of access by traditional procedures. Biohalogenation—particularly by fungi—is noted, though its quantitative contribution cannot be estimated at the moment. A number of important unresolved issues are underscored: (a) the problem of determining rates of microbial reactions which may be translated to environmental situations, (b) the cardinal role not only of the number of chlorine atoms in an aromatic compound but also the substitution pattern and (c) limitations in current understanding of the role of anaerobic bacteria in bringing about biodegradation and biotransformation.     

On the intrinsic structure of differential equation models of ecosystems

Some intrinsic properties of differential equation models of ecosystems are formulated. The properties, which are long-termed, are classified into fundamental, stability, and sensitivity substructures. An aspect of the ecological term “resilient” — asymptotic stability uniformly for all small parameter variations — is introduced in a mathematical setting. In the sensitivity substructure, bounded sensitivity and continuity of sensitivity with respect to solutions are recognized as intrinsic properties. Illustrations of these two properties are given.     

The Future of Scattered Trees in Agricultural Landscapes

Abstract: Mature trees scattered throughout agricultural landscapes are critical habitat for some biota and provide a range of ecosystem services. These trees are declining in intensively managed agricultural landscapes globally. We developed a simulation model to predict the rates at which these trees are declining, identified the key variables that can be manipulated to mitigate this decline, and compared alternative management proposals. We used the initial numbers of trees in the stand, the predicted ages of these trees, their rate of growth, the number of recruits established, the frequency of recruitment, and the rate of tree mortality to simulate the dynamics of scattered trees in agricultural landscapes. We applied this simulation model to case studies from Spain, United States, Australia, and Costa Rica. We predicted that mature trees would be lost from these landscapes in 90–180 years under current management. Existing management recommendations for these landscapes—which focus on increasing recruitment—would not reverse this trend. The loss of scattered mature trees was most sensitive to tree mortality, stand age, number of recruits, and frequency of recruitment. We predicted that perpetuating mature trees in agricultural landscapes at or above existing densities requires a strategy that keeps mortality among established trees below around 0.5% per year, recruits new trees at a rate that is higher than the number of existing trees, and recruits new trees at a frequency in years equivalent to around 15% of the maximum life expectancy of trees. Numbers of mature trees in landscapes represented by the case studies will decline before they increase, even if strategies of this type are implemented immediately. This decline will be greater if a management response is delayed.