Integrated modelling of the ecosystem of the Niger river inland delta in Mali

The Niger River inland delta in Mali constitutes a vast 36,000 km² area of wetlands, producing numerous natural resources, exploited by fishermen, pastoralists and farmers. It is also a humid zone protected through the Ramsar convention of 1971. To promote the management of its natural resources, an integrated model has been developed in order to simulate the evolution of this ecosystem in relation to different scenarios of population increase, diminishing natural flooding (climatic droughts, construction of dams), increasing stress on land tenure and access to farming areas, technological advances, current administrative decentralisation policy. Possible applications of the model are illustrated through an analysis of the impact of the construction of dams on the traditional farming systems of the delta (fishing, rice cropping, pastoralism), and through a sensitivity analysis of an evolution in the fishing techniques on the revenues of fishermen. The validity of the results of the modelling is discussed and its use for other studies in the field of integrated natural resources management analysed.     

Habituation and song repertoires in the great tit

Summary This paper is concerned with the idea that the song repertoires of passerine birds are an evolutionary adaptation to reduce habituation in listeners. In an experiment involving 16 territorial males I played either a single song or a repertoire of songs for 15 two-min trials through a single loudspeaker near the edge of the territory. In a second experiment with 10 birds I played the songs through one of two loudspeakers in different parts of the territory, alternating between loudspeakers on successive trials. The birds tended to habituate more rapidly to single song playback than to repertoires. In the second experiment the overall level of habituation was lower and the difference between the two treatments was less marked.Two features of song repertoire organisation are consistent with the habituation hypothesis (1) the avoidance of low recurrence intervals in switches between song types, and (2) the fact that within repertoire variability is as great or greater than between repertoire varability.The main problem with the habituation hypothesis is that habituation by listeners does not seem to be adaptive, so it is not clear why they should habituate. I suggest a hypothesis. Intruders may assess the density of birds in an area by listening to songs, so that habituation may be a mechanism by which this density assessment is achieved. Repertoires could be a mechanism by which resident birds cheat, through increasing the apparent density of singing birds.     

Conservation of the Toromiro Tree: Case Study in the Management of a Plant Extinct in the Wild

Abstract: We reviewed the history and conservation of Sophora toromiro , a species that has been extinct in the wild since 1960 but has survived as scattered individuals in botanic gardens and private collections. The short-term conservation of S. toromiro is dependent on the management of surviving ex situ stocks. This is being achieved through international collaboration by a working group established to coordinate the conservation management of the species. Molecular evidence indicates that the species retains greater genetic variability than expected. The greatest amount of genetic variability was located in specimens outside botanic garden collections. No unmodified natural habitat survives on Rapa Nui ( Easter Island); so opportunities to establish a viable wild population are limited. Evidence from past reintroductions indicates that the best short-term opportunity for the species is through conventional horticultural management in botanic gardens and traditional farm plots on Rapa Nui. Some extinct-in-the-wild taxa (sensu World Conservation Union 1994), such as the Toromiro, retain genetic variability, and appropriate reintroduction sites exist. These taxa represent valid priorities for conservation management.     

Gap Crossing Decisions by Forest Songbirds during the Post-Fledging Period

Gaps in forest cover, created by agriculture, forestry, and other anthropogenic activities, are assumed to impede the movements of many forest songbirds. Little is known, however, about the reluctance of different species of birds to cross habitat gaps. We studied this by inducing birds in the post-fledging period to cross gaps of varying widths and to choose between routes through woodland or across open areas by attracting them to a recording of mobbing calls by Chickadees (  Parus atricapillus). In 278 experiments conducted in boreal forest and agricultural landscapes near Québec city, 157 birds or flocks of birds of five species were attracted. Overall, birds were twice as likely to travel through 50 m of woodland than through 50 m in the open to reach the recording. When given a choice of traveling through woodland or across a gap, the majority of respondents preferred woodland routes, even when they were three times longer than shortcuts in the open. However, species differed greatly in their response to gaps. Our results show that woodland links significantly facilitate movements of birds across fragmented landscapes.     

Measuring sustainable governance in the European Union

This paper examines the problem of measuring sustainable governance in the European Union (EU-27) through the use of duality and the Slutsky equation. The proposed methodology is based on the application of a three-dimensional optimisation model, where the arguments of the objective (sustainable social welfare) function are economic goods that contribute to sustainable economic growth; environmental goods that provide for sustainable environmental protection; and social goods through which sustainable social development is achieved. The dual problem, formulated through this three-dimensional theoretical model, is solved to find the optimal solution, indicating a certain sustainability level. We suggest that this solution can be used for calculating the value of what we define here as the sustainable governmental policy indicator, which is considered to provide quantitative measurement of government policies on sustainable development within the context of ‘good governance’. Furthermore, it is suggested that the Slutsky equation can be used as a reliable method for long-term monitoring and planning of national as well as international good governance with regard to sustainable development policies. In its empirical part, the paper applies the theoretical model in an analysis of the sustainable development indicators (as set out in the Sustainable Development Strategy (SDS) of the EU) in Bulgaria for the period 2000–2010 and compares them to those of the EU-27.     

Influence of pore size of plankton nets and towing speed on the sampling performance of two high-speed samplers (Delfino I and II) and its consequences for the assessment of plankton populations

The sampling performance of two high-speed samplers, (Delfino I and II), fitted with a calibrated flow meter, was studied in the open Ligurian Sea using a battery comprising 6 such Delfinos linked together. Since, in plankton counts, only those organisms should be counted which are definitely retained in the nets, several techniques for the separation of the organisms which pass through the pore of a net of a given pore size and those which are safely retained were tested. Attempts to separate these two fractions by filtration of the fixed sample through nets of different pore sizes were not successful, as living organisms were able to pass through pore sizes which retained dead organisms. However, optical sizing under the dissecting microscope during counting gave reproducible results. Using this counting technique, the influence of the pore size of plankton nets on the reproducibility of sampling of natural populations was studied. The results obtained show that live plankton passes through the net pores at a size at which fixed plankton is retained. Hence, the minimum retention size for living and dead plankton is different. By comparing samples taken with nets of different pore sizes, and counting the organisms caught according to different sizes, it was possible to determine the minimum retention size of live plankton organisms for several different net pore-sizes. The minimum retention size is, therefore, the smallest pore size at which the organisms of a certain width cannot escape through the pores of the net and are, thus, quantitatively retained in the net. By applying the criterion of minimum retention size, the influence of speed towing on the number of plankton organisms caught was studied. It was shown that the number of organisms which are safely retained, i.e., do not escape through the pores, increased with speed, reaching a plateau at 5 to 7 knots.A contribution under the Association Contract CNEN-EURATOM. Contribution No. 668 of the Euratom Biology Division.     

Estimating the direct and indirect impact of typhoons on plant performance: Evidence from Chinese manufacturers

We quantify the impact of typhoons on manufacturing plants in China. To this end we construct a panel data set of precisely geo-located plants and a plant-level measure of typhoon damage derived from storm track data and a wind field model. Our econometric results reveal that the impact on plant sales can be considerable, although the effects are relatively short-lived. Annual total costs to Chinese plants from typhoons are estimated to be in the range of US$ 3.2 billion (2017 prices), or about 1 per cent of average turnover. When we examine the channels by which plants react to a storm event we find that there is some buffering through an increase in debt and a reduction in liquidity. In terms of propagating the shock through foreign or domestic channels, our estimates suggest that plants prefer to reduce sales to domestic buyers more than foreign buyers and purchases from foreign rather than domestic suppliers. We also find some evidence of a negative indirect effect on turnover through spillovers from customers and a positive effect through damage to very nearby competitors.     

Life cycle assessment and sustainable engineering in the context of near net shape grown components: striving towards a sustainable way of future production

Technical product harvesting (TEPHA) is a newly developing interdisciplinary approach in which bio-based production is investigated from a technical and ecological perspective. Society‘s demand for ecologically produced and sustainably operable goods is a key driver for the substitution of conventional materials like metals or plastics through bio-based alternatives. Technical product harvesting of near net shape grown components describes the use of suitable biomass for the production of technical products through influencing the natural shape of plants during their growth period. The use of natural materials may show positive effects on the amount of non-renewable resource consumption. This also increases the product recyclability at the end of its life cycle. Furthermore, through the near net shape growth of biomass, production steps can be reduced. As a consequence such approaches may save energy and the needed resources like crude oil, coal or gas. The derived near net shape grown components are not only considered beneficial from an environmental point of view. They can also have mechanical advantages through an intrinsic topology optimization in contrast to common natural materials, which are influenced in their shape after harvesting. In order to prove these benefits a comprehensive, interdisciplinary scientific strategy is needed. Here, both mechanical investigations and life cycle assessment as a method of environmental evaluation are used.     

Bridging the gap between ecophysiological and genetic knowledge to assess the adaptive potential of European beech

In this study we aimed to combine knowledge of the ecophysiology and genetics of European beech to assess the potential of this species to adapt to environmental change. Therefore, we performed field and experimental studies on the genetic and ecophysiological functioning of beech. This information was integrated through a coupled genetic–ecophysiological model for individual trees that was parameterized with information derived from our own studies or from the literature. Using the model, we evaluated the adaptive response of beech stands in two ways: firstly, through sensitivity analyses (of initial genetic diversity, pollen dispersal distance, heritability of selected phenotypic traits, and forest management, representing disturbances) and secondly, through the evaluation of the responses of phenotypic traits and their genetic diversity to four management regimes applied to 10 study plots distributed over Western Europe. The model results indicate that the interval between recruitment events strongly affects the rate of adaptive response, because selection is most severe during the early stages of forest development. Forest management regimes largely determine recruitment intervals and thereby the potential for adaptive responses. Forest management regimes also determine the number of mother trees that contribute to the next generation and thereby the genetic variation that is maintained. Consequently, undisturbed forests maintain the largest amount of genetic variation, as recruitment intervals approach the longevity of trees and many mother trees contribute to the next generation. However, undisturbed forests have the slowest adaptive response, for the same reasons.Gene flow through pollen dispersal may compensate for the loss in genetic diversity brought about by selection. The sensitivity analysis showed that the total genetic diversity of a 2 ha stand is not affected by gene flow if the pollen distance distribution is varied from highly left-skewed to almost flat. However, a stand with a prevailing short-distance gene flow has a more pronounced spatial genetic structure than stands with equal short- and long-distance gene flows. The build-up of a spatial genetic structure is also strongly determined by the recruitment interval. Overall, the modelling results indicate that European beech has high adaptive potential to environmental change if recruitment intervals are short and many mother trees contribute to the next generation.The findings have two implications for modelling studies on the impacts of climate change on forests. Firstly: it cannot be taken for granted that parameter values remain constant over a time horizon of even a few generations – this is particularly important for threshold values subject to strong selection, like budburst, frost hardiness, drought tolerance, as used in species area models. Secondly: forest management should be taken into account in future assessments, as management affects the rate of adaptive response and thereby the response on trees and forests to environmental change, and because few forests are unmanaged. We conclude that a coupled ecophysiological and quantitative genetic tree model is a useful tool for such studies.     

Breaking through the Crisis in Marine Conservation and Management: Insights from the Philosophies of Ed Ricketts

Abstract:  Over the last decade, 2 major U.S. commissions on ocean policy and a wide range of independent sources have argued that ocean ecosystems are in a period of crisis and that current policies are inadequate to prevent further ecological damage. These sources have advocated ecosystem-based management as an approach to address conservation issues in the oceans, but managers remain uncertain as to how to implement ecosystem-based approaches in the real world. We argue that the philosophies of Edward F. Ricketts, a mid-20th-century marine ecologist, offer a framework and clear guidance for taking an ecosystem approach to marine conservation. Ricketts' philosophies, which were grounded in basic observations of natural history, espoused building a holistic picture of the natural world, including the influence of humans, through repeated observation. This approach, when applied to conservation, grounds management in what is observable in nature, encourages early action in the face of uncertainty, and supports an adaptive approach to management as new information becomes available. Ricketts' philosophy of "breaking through," which focuses on getting beyond crisis and conflict through honest debate of different parties' needs (rather than forcing compromise of differing positions), emphasizes the social dimension of natural resource management. New observational technologies, long-term ecological data sets, and especially advances in the social sciences made available since Ricketts' time greatly enhance the utility of Ricketts' philosophy of marine conservation.     

全氟辛烷磺酸神经发育毒性机制研究进展

全氟辛烷磺酸(PFOS)是全氟化合物的终端降解产物,在生态环境中能够通过食物链进入生物组织并蓄积,对环境和生物存在潜在危害。动物实验研究发现,PFOS能够通过胎盘和血脑屏障,影响发育期神经系统,其持续性和严重性已引起国内外学者的广泛关注。本文通过对PFOS神经发育毒性效应及其主要机制研究进展进行综述,分析目前研究现状,并对未来PFOS神经发育毒性机制研究提出设想和展望。     

Applying the dark diversity concept to nature conservation

Linking diversity to biological processes is central for developing informed and effective conservation decisions. Unfortunately, observable patterns provide only a proportion of the information necessary for fully understanding the mechanisms and processes acting on a particular population or community. We suggest conservation managers use the often overlooked information relative to species absences and pay particular attention to dark diversity (i.e., a set of species that are absent from a site but that could disperse to and establish there, in other words, the absent portion of a habitat‐specific species pool). Together with existing ecological metrics, concepts, and conservation tools, dark diversity can be used to complement and further develop conservation prioritization and management decisions through an understanding of biodiversity relativized by its potential (i.e., its species pool). Furthermore, through a detailed understanding of the population, community, and functional dark diversity, the restoration potential of degraded habitats can be more rigorously assessed and so to the likelihood of successful species invasions. We suggest the application of the dark diversity concept is currently an underappreciated source of information that is valuable for conservation applications ranging from macroscale conservation prioritization to more locally scaled restoration ecology and the management of invasive species.     

Investigation of the flow structures through heterogeneous vegetation of varying patch configurations in an open channel

Environmental Fluid Mechanics - The hydrodynamics of flow passing through heterogeneous vegetation configurations is always complex and it becomes difficult to capture the flow structures through...     

Voluntary participation for sustainability transition: experiences from the ‘Commitment to Sustainable Development 2050’

Voluntary and active participation by a wide variety of actors is a prerequisite for successful societal transitions towards sustainability. The ‘Commitment to Sustainable Development 2050’ is a national-level initiative in Finland, aiming to mobilise a large-scale transition involving various societal actors through openly communicated commitments to concrete actions. Each commitment should focus on at least one of the eight nationally defined sustainability objectives connected to the global Sustainable Development Goals. This article assesses the implementation and the development needs of the commitment process based on a range of materials. The results highlight the importance of securing adequate resources for long-term coordination and continuous development of the commitment process, trust creation through long-term and open communication, and flexibility allowing for experimentation aimed at finding new modes of interaction between the public and private sectors.     

Analysis of the relations between circular economy and sustainable development goals

ABSTRACT

Since the United Nations approved the eight Millennium Development Goals in 2000 and, 15 years later, the 2030 Agenda for Sustainable Development and its 17 Sustainable Development Goals (SDGs), the highest political institutions in the world have not stopped worrying about achieving the sustainability of the planet. Also in 2015, the European Commission prepared the European Union Action Plan for the Circular Economy, seeking a transition towards a less linear economy, in which products, materials, and resources are kept in the system for as long as possible and in which the generation of waste is minimized.

Since then, the European Union has continued issuing reports and communications to accelerate this process in search of a circular economy, making continuous references to the fact that, through circular economy initiatives, the SDGs would be fulfilled. In this context, the objectives of this paper are 1) to determine, through exploratory factor analysis and correlation analysis, whether there is a statistically significant relationship between circular economy initiatives undertaken in the EU and compliance with the SDGs; 2) to check, through a cluster analysis, if there are homogeneous groups of countries worldwide in terms of compliance with the SDGs; and 3) using this same technique, to check whether the countries that make up the EU achieve similar results in terms of compliance with the SDGs.     

Assessing Conservation Management's Evidence Base: a Survey of Management-Plan Compilers in the United Kingdom and Australia

Abstract:  Conservation management is becoming increasingly resource intensive as threats to biodiversity grow through habitat destruction, habitat disturbance, and overexploitation. To achieve successful conservation and sustainable use of natural resources, we need to scientifically evaluate the effectiveness of conservation interventions and provide an efficient framework through which scientific evidence can be used to support decision making in policy and practice. We conducted the first formal assessment of the extent to which scientific evidence is used in conservation management through a questionnaire survey and follow-up interviews of compilers of protected-area management plans from major conservation organizations within the United Kingdom and Australia. Our survey results show that scientific information is not being used systematically to support decision making largely because it is not easily accessible to decision makers. This, in combination with limited monitoring and evaluation of effectiveness of management interventions, results in the majority of decisions being based on experience rather than on evidence. To address this problem we propose using an evidence-based framework adapted from that used in the health services and explain how we are currently putting an equivalent framework into practice by establishing review and dissemination units to serve the conservation sector.     

Dredged Material Disposal at the Edge of the Florida Current

A field data collection project was undertaken to investigate the short-term fate of dredged material discharged in the designated Miami Ocean Dredged Material Disposal Site (ODMDS) before dredging of the Miami River and the Miami Harbor Turning Basin begins. the designated ODMDS is located in relatively deep water for discharge sites with a typical bottom depth of 150 metres and is also located in the western boundary region of the Gulf Stream current off Miami. Acoustical backscattering, current, particulate, temperature and salinity data were gathered over a three day period from April 24, 1990 through April 26, 1990. the major generic features of shallow-water discharge plumes were observed to be present: (a) the presence of a rapid convective descending plume portion; (b) impact of that plume portion with the ocean bottom and concomitant generation of a bottom surge; (c) rapid horizontal width growth of the descending plume through entrainment; and (d) retention of a residual plume portion within the water column. A well-mixed upper water column layer extending to a depth of 40 to 60 metres below the surface of the ocean permitted measurements of the plume entrainment coefficient free from bottom boundary, water column density gradient, and vertical current shear effects which are usually present in relatively shallow, e.g. less than 40 metres bottom depth, coastal ocean discharge studies. Entrainment coefficient estimates obtained in this study were between 0.5 to 0.7. the residual water plume material was tracked over one-half hour during each of eight discharge events and was transported in a north-northeast direction.     

Dredged Material Disposal at the Edge of the Florida Current

A field data collection project was undertaken to investigate the short-term fate of dredged material discharged in the designated Miami Ocean Dredged Material Disposal Site (ODMDS) before dredging of the Miami River and the Miami Harbor Turning Basin begins. the designated ODMDS is located in relatively deep water for discharge sites with a typical bottom depth of 150 metres and is also located in the western boundary region of the Gulf Stream current off Miami. Acoustical backscattering, current, particulate, temperature and salinity data were gathered over a three day period from April 24, 1990 through April 26, 1990. the major generic features of shallow-water discharge plumes were observed to be present: (a) the presence of a rapid convective descending plume portion; (b) impact of that plume portion with the ocean bottom and concomitant generation of a bottom surge; (c) rapid horizontal width growth of the descending plume through entrainment; and (d) retention of a residual plume portion within the water column. A well-mixed upper water column layer extending to a depth of 40 to 60 metres below the surface of the ocean permitted measurements of the plume entrainment coefficient free from bottom boundary, water column density gradient, and vertical current shear effects which are usually present in relatively shallow, e.g. less than 40 metres bottom depth, coastal ocean discharge studies. Entrainment coefficient estimates obtained in this study were between 0.5 to 0.7. the residual water plume material was tracked over one-half hour during each of eight discharge events and was transported in a north-northeast direction.     

企业融资决策由于新会计准则而产生的影响因素分析

融资是企业筹集资金目前经常会运用的方式,企业融资就是指因为企业需要调整资本结构、生产经营管理、对外投资决策一系列活动希望通过金融机构和金融市场,运用适当的方式及手段获取所需资金的一种理财活动.企业获得资金转移信息的主要渠道是来自于会计领域,那么新企业会计准则制度的实施,必然有一些新的规定将对企业融资决策产生影响,此篇论文就将从这个角度探讨.