Rehabilitating degraded forests in Central Europe into self–sustaining forest ecosystems

There is a need for a consistent forest restoration strategy for the `Black Triangle', Central Europe. In the past 50 years, forests in this area have been heavily affected by industrial pollution. Recently, the amount of pollutants has decreased. This means that effective forest restoration programmes can be started. Forest decline must be seen as an ecological disturbance which cannot be solved by applying technical measures only. An ecosystem approach to forest restoration must be introduced into restoration policy and management. Basic principles and working methods of such an approach are briefly described and proposals are made for forest restoration policy, management and research in the area.     

The Høylandet area – patterns and processes of a pristine boreal-subalpine ecosystem – a synopsis

The research activities on soil–freshwaterinteractions and freshwater biotic structure andprocesses in the Høylandet area during the years 1986–89are presented in this issue ofHydrobiologia. The 9 papers cover a range of topicsfrom physiochemical gradients and processes in soilsand freshwaters to selected aspects of freshwaterbiotic community structure and temporal variability.This synopsis aims (a) to present an overview of majorfindings, (b) to interpret the results in the contextof air pollution effects and (c) to outlinesuggestions for future research activities inHøylandet. The area has a sub-oceanic climate varyingfrom 1100 to 2200 mm of precipitation normallyoriginating from unpolluted airmasses from the NorthAtlantic. It is chemically dominated by sea salts, haslow concentrations and low deposition of mineralacids. The catchment geology is variable and complexand consists mainly of various granites and gneisses.The soils are undisturbed ancient soils,primarily iron podzols associated with forests, orintact histosols with strong organic characterassociated with mires, often quite acidic.They are sensitive because occurrence of predominantlyinsoluble unstable Al-complexes may leach out ifexposed to anthropogenically acidified soil drainagewater and turn up as toxic inorganic aqueous Al insurface runoff. Small amounts of locally generatednitrogen compounds are mostly retained in thecatchment. The water qualities of these Høylandetsites are run by inputs of sea salts, hydrologicalprocesses including dilution of the base flow, orlateral surface or overland flow and in-catchmentprocesses. Relative to affected areas, it appears thatthe inputs and catchment processes are in balance,i.e., that the inputs of strong acid anions, hydrogenions and sea salts are equilibrated by internalweathering and other processes and integrated withinapparently intact biogeochemical cycles. The overallresult is that these soils remain a net source ofalkalinity to the runoff. These results are confirmedby regional studies of water quality both at low andhigh flow which show that the humus and ionic contentof the water decreased with elevation, headwatersbeing more dominated by sea salts and dilutionprocesses. Excess sulphate concentrations are low, andfew if any sites appear anthropogenically acidified,the most acid pHs reflecting presence of natural weakorganic acids.The resulting surface water quality allows a diverseaquatic fauna and flora with representatives of manyacid-sensitive groups. The fish fauna consists ofself-reproducing salmonid populations with normaldemography and ecological interactions. Despite highin-lake mortality, both brown trout and Arctic charrexhibited normal age-class compositions, with noindication of the recruitment failure or highpost-spawning mortality commonly observed inacid-stressed situations. The zooplankton and benthos in the lakesare inhabited by populations of several acid sensitivespecies, like Daphnia spp and Gammaruslacustris, and with dominance of mayfly species ofthe genus Baetis in the stream fauna. Thediatom flora includes many species which are rare orabsent in acidified waters. The observed gradients indiversity and biomass seem dominated by localenvironmental conditions which reflect natural ratherthan man-made processes. The pristine nature of thearea also emerges from the paleoecological studies inLake Røyrtjønna which show that the low acidity ofthis lake evironment has persisted from preindustrialtill present times. Suggestion for future researchactivities in Høylandet are outlined.     

Naltrexone partially inhibits the estrogen-induced increase in prolactin secretion and anterior pituitary weight

The effects of naltrexone, a specific opiate antagonist, on stimulation by estradiol benzoate (EB) of prolactin (PRL) release and anterior pituitary (AP) weight, were studied in gonadectomized female and male Sprague-Dawley rats. One week after castration, rats were injected for 10 days once daily with 2 μg EB alone, or together with twice daily injections of 2 mg naltrexone/kg body weight (BW). Blood was collected for radioimmunoassay of PRL by orbital sinus puncture on days 0 and 6, and by decapitation on day 11, at which time the AP was quickly removed, weighed and assayed for PRL.Serum PRL concentrations and AP weights were significantly increased by EB administration. These effects of EB were partially but significantly inhibited by naltrexone. These results suggest that endegenous opiates may be involved in the estrogen-induced rise in serum PRL and increase in pituatary weight.     

Can the problem of hybridization in threatened species be evaluated using a fieldwork research? A case study in snapdragons

Hybridization, natural or artificial, is considered disadvantageous for species biodiversity when it threatens the population integrity of endangered species. Frequently, studies investigating whether hybridization poses a legitimate risk to rare species are based on genetic data obtained in molecular biology laboratories. In this study, we used field research to approach the problem that hybridization could cause for the viability of a population of a rare species and to be able to propose the most appropriate initial conservation strategy. Specifically, using the model genus Antirrhinum, the reproductive barriers between the rare A. pulverulentum and its common congener A. litigiosum have been analysed under the reproductive isolation index (RI). A. pulverulentum had a high value of total RI, indicating that there are barriers to gene flow from A. litigiosum towards this species, and also had a high value for the intrinsic RI, reflecting a low inherent capacity for production of hybrid plants; in addition, the possibility of successful backcrosses between this species with hybrids produced from A. litigiosum ovules were low, given the high intrinsic RI of A. litigiosum. These data indicate the current existence of strong and permanent barriers to hybridization between the two species, suggesting that hybridization does not seem to be a serious problem for the conservation of A. pulverulentum in the studied population, nor for the near future. This study shows how the RI index can provide useful information for conservation purposes and proposes different management recommendations.     

CULTURE AND GENETIC SCREENING IN AFRICA

Africa is a continent in transition amidst a revival of cultural practices. Over previous years the continent was robbed of the benefits of medical advances by unfounded cultural practices surrounding its cultural heritage. In a fast moving field like genetic screening, discussions of social and policy aspects frequently need to take place at an early stage to avoid the dilemma encountered by Western medicine. This paper, examines the potential challenges to genetic screening in Africa. It discusses how cultural practices may affect genetic screening. It views genomics science as a culture which is trying to diffuse into another one. It argues that understanding the existing culture will help the diffusion process. The paper emphasizes the importance of genetic screening for Africa, by assessing the current level of burden of diseases in the continent and shows its role in reducing disease prevalence. The paper identifies and discusses the cultural challenges that are likely to confront genetic screening on the continent, such as the worldview, rituals and taboos, polygyny, culture of son preference and so on. It also discusses cultural practices that may promote the science such as inheritance practices, spouse selection practices and naming patterns. Factors driving the cultural challenges are identified and discussed, such as socialization process, patriarchy, gender, belief system and so on. Finally, the paper discusses the way forward and highlights the ethical considerations of doing genetic screening on the continent. However, the paper also recognizes that African culture is not monolithic and therefore makes a case for exceptions.     

Dispersal traits as indicators of vegetation dynamics in long-term old-field succession

Succession is a key ecological process that supports our understanding of community assembly and biotic interactions. Dispersal potential and dispersal strategies, such as wind- or animal-dispersal, have been assumed to be highly relevant for the success of plant species during succession. However, research yielded varying results on changes in dispersal modes between successional stages. Here, we test the hypotheses that (a) vascular plant species that use a number of dispersal modes dominate in early stages of succession while species specialized on one/few dispersal modes increase in abundance towards later stages of succession; (b) species well adapted to wind-dispersal (anemochory) will peak in abundance in early successional stages and (c) species well adapted to adhesive dispersal (epizoochory) will increase with proceeding succession. We test these hypotheses in four sites within agriculturally dominated landscapes in Germany. Agricultural use in these sites was abandoned 20–28 years ago, leaving them to secondary succession. Sites have been monitored for plant biodiversity ever since. We analyze changes in plant species richness and abundance, number of dispersal modes and two ranking indices for wind- and adhesive dispersal by applying generalized linear mixed-effect models. We used both abundance-weighted and unweighted dispersal traits in order to gain a comprehensive picture of successional developments. Hypothesis (a) was supported by unweighted but not abundance-weighted data. Anemochory showed no consistent changes across sites. In contrast, epizoochory (especially when not weighted by abundance) turned out to be an indicator of the transition from early to mid-successional stages. It increased for the first 9–16 years of succession but declined afterwards. Species richness showed an opposing pattern, while species abundance increased asymptotically. We suggest that plant-animal interactions play a key role in mediating these processes: By importing seeds of highly competitive plant species, animals are likely to promote the increasing abundance of a few dominant, highly epizoochorous species. These species outcompete weak competitors and species richness decreases. However, animals should as well promote the subsequent increase of species richness by disturbing the sites and creating small open patches. These patches are colonized by weaker competitors that are not necessarily dispersed by animals. The changes in the presence of epizoochorous species indicate the importance of plant traits and related plant–animal interactions in the succession of plant communities.     

Using,risking, and consent: Why risking harm to bystanders is morally different from risking harm to research subjects

Subjects in studies on humans are used as a means of conducting the research and achieving whatever good would justify putting them at risk. Accordingly, consent must normally be obtained before subjects are exposed to any substantial risks to their welfare. Bystanders are also often put at risk, but they are not used as a means. Accordingly—or so I argue—consent is more often unnecessary before bystanders are exposed to similar substantial risks to their welfare.     

Bystanders and ethical review of research: Proceed with caution

Scientists seeking to conduct research with human subjects must first submit their proposals to research ethics committees (Institutional Review Boards [IRBs], in the United States). Some of these studies pose risks to “bystanders,” i.e., people who may be affected by the research but who are not enrolled as study subjects. Should IRBs expand their scope to include oversight over possible harms to bystanders as well as research subjects? This paper presents arguments against this step. Prior review of research with human subjects, despite its evident burden on the research enterprise, is a necessary caution, because the tension between the objectives of humane treatment of research subjects and sound scientific design and procedure has in the past led to serious abuses. This rationale is inapplicable in the case of bystanders. Moreover, in view of the many and varied effects of both research practices and scientific advances on the broader public over time, those who may be considered to be “bystanders” may potentially expand without limit; requiring IRBs to anticipate these distant and long-term effects as part of prior ethical review could greatly increase its burden and its deterrent effect on research. While conducting research without concern for serious potential harm to bystanders may be irresponsible and unethical, expanding the scope of prior review by IRBs to include risks to bystanders is not required by the principles governing human subjects research, and the costs and burdens of this expansion may outweigh any expected gains.     

与蝉花有关的虫草菌生物多样性的研究I：文献考证

蝉花是我国重要药用真菌,但长期以来其名称特别是学名的使用一直混乱。本文从古代医药典籍记载确认,“蝉花”是历史最久、使用最广的中名,对于其他中名具有优先权。其学名Isaria cicadae系Miquel（1838）根据巴西标本命名,但模式标本已失,原描述文字及插图均极其简单,与蝉花形态差异较大。其有性型迄今未发现,曾先后被认为是小蝉草Ophiocordyceps sobolifera和大蝉草Tolypocladium dujiaolongae (=Cordyceps cicadae Shing)。本文根据文献考证澄清了国内外关于小蝉草和大蝉草的误用,分析了长期以来大量日本文献中的命名混乱对我国认知蝉花的影响,并质疑I. cicadae在中国及其他地区的分布,提出它是一复合种,因此蝉花的分类地位及学名需要进一步研究。