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351.
352.
Andreas Meyer-Aurich Jørgen E. Olesen Annette Prochnow Reiner Brunsch 《Mitigation and Adaptation Strategies for Global Change》2013,18(7):921-932
Agricultural lands have been identified to mitigate greenhouse gas (GHG) emissions primarily by production of energy crops and substituting fossil energy resources and through carbon sequestration in soils. Increased fertilizer input resulting in increased yields may reduce the area needed for crop production. The surplus area could be used for energy production without affecting the land use necessary for food and feed production. We built a model to investigate the effect of changing nitrogen (N) fertilizer rates on cropping area required for a given amount of crops. We found that an increase in nitrogen fertilizer supply is only justified if GHG mitigation with additional land is higher than 9–15 t carbon dioxide equivalents per hectare (CO2-eq../ha). The mitigation potential of bioenergy production from energy crops is most often not in this range. Hence, from a GHG abatement point of view land should rather be used to produce crops at moderate fertilizer rate than to produce energy crops. This may change if farmers are forced to reduce their N input due to taxes or governmental regulations as it is the case in Denmark. However, with a fertilizer rate 10 % below the economical optimum a reduction of N input is still more effective than the production of bioenergy unless mitigation effect of the bioenergy production exceeds 7 t carbon dioxide (CO2)-eq../ha. An intensification of land use in terms of N supply to provide more land for bioenergy production can only in exceptional cases be justified to mitigate GHG emissions with bioenergy under current frame conditions in Germany and Denmark. 相似文献
353.
Gooneratne R Buser A Lindsay P Wellby M 《Journal of environmental monitoring : JEM》2011,13(5):1360-1365
Ecological health of 15 sites in two mining areas on the West Coast of the South Island, New Zealand, was assessed using a non-invasive electrophysiological technique. The conduction velocity (CV) changes in the medial giant fibres (MGF) of the terrestrial earthworm Aporrectodea caliginosa were measured on days 0, 1, 2, 4, 7, 14, and 21 following exposure to soil and/or sediment from six acid mine drainage (AMD) sites, and aquatic oligochaete Lumbriculus variegatus at 0, 3, 6, and 24 h following exposure to water from 14 AMD sites. The colour of the soil/sediments varied from red-brown to black with pH ranging from 4.46 to 7.37. The colour of AMD water samples varied from clear, black, brown to orange, and the pH ranged from 2.99 to 7.66. The CV decreased progressively in A. caliginosa exposed to most soil and sediment samples from the AMD sites (compared with controls exposed to soil from an organic farm) and this was most evident in measurements taken at 7 days. Based on the CV measurements taken on day 7, sites 3 > 2 > 1 were significantly (P < 0.05) the most toxic to earthworms. The CV of L. variegatus exposed to AMD water sampled from many sites also decreased progressively and this was significantly lower than the controls in the measurements taken at 24 h from sites 3 > 9 > 7 > 11. It is proposed that MGF CV in A. caliginosa and L. variegatus worms can be used as a non-invasive, sensitive, biomarker to monitor the toxicity of AMD sites. 相似文献
354.
Andreas Egelund Christensen 《Natural resources forum》2011,35(1):9-20
The rise and fall of the bêche‐de‐mer trade in Solomon Islands is an example of how small, remote island communities are influenced by drivers of change on both the national and international scales. This susceptibility leads to local economic collapses and changed livelihoods. This article focuses on small‐island livelihoods, socio‐economic responses to fluctuating markets and the instability caused by internal and external forces of change. Quantitative surveys, qualitative interviews and participant observation have been used to explore the development trajectories of Ontong Java, a Polynesian outlier in Solomon Islands, in the context of the bêche‐de‐mer trade over the past forty years. The main findings can be captured in four distinct periods that demonstrate the transformation of this atoll community from subsistence‐oriented strategies to specialization in marine resource extraction to economic collapse and return to subsistence. It is concluded that this atoll population has shown a remarkable ability to adjust and cope with processes of globalization. 相似文献
355.
Integrating Landscape Ecology and Geoinformatics to Decipher Landscape Dynamics for Regional Planning 总被引:1,自引:0,他引:1
We used remote sensing and GIS in conjunction with multivariate statistical methods to: (i) quantify landscape composition
(land cover types) and configuration (patch density, diversity, fractal dimension, contagion) for five coastal watersheds
of Kalloni gulf, Lesvos Island, Greece, in 1945, 1960, 1971, 1990 and 2002/2003, (ii) evaluate the relative importance of
physical (slope, geologic substrate, stream order) and human (road network, population density) variables on landscape composition
and configuration, and (iii) characterize processes that led to land cover changes through land cover transitions between
these five successive periods in time. Distributions of land cover types did not differ among the five time periods at the
five watersheds studied because the largest cumulative changes between 1945 and 2002/2003 did not take place at dominant land
cover types. Landscape composition related primarily to the physical attributes of the landscape. Nevertheless, increase in
population density and the road network were found to increase heterogeneity of the landscape mosaic (patchiness), complexity
of patch shape (fractal dimension), and patch disaggregation (contagion). Increase in road network was also found to increase
landscape diversity due to the creation of new patches. The main processes involved in land cover changes were plough-land
abandonment and ecological succession. Landscape dynamics during the last 50 years corroborate the ecotouristic-agrotouristic
model for regional development to reverse trends in agricultural land abandonment and human population decline and when combined
with hypothetical regulatory approaches could predict how this landscape could develop in the future, thus, providing a valuable
tool to regional planning. 相似文献
356.
Topi K. Lehtonen Bob B. M. Wong P. Andreas Svensson Axel Meyer 《Behavioral ecology and sociobiology》2011,65(4):613-619
In many taxa, parental strategies can vary among individuals. This is especially true in species with biparental care, with
males, more often than females, deserting their mates. While there is an abundance of theoretical predictions and empirical
data on factors inducing mate abandonment by males, much less is known about what consequences this may have on female behaviour,
particularly in the field and in non-avian systems. Here, we compared brood defence rate, behavioural defence types, and brood
success of solitary and paired females in two species of Neotropical cichlid fish in their natural habitat. In terms of the
rate of territorial aggression towards potential brood predators, solitary females were able to fully compensate in the absence
of a male but, in so doing, ended up maintaining smaller territories, which appeared to compromise offspring fitness in at
least one of the two species. Hence, our results suggest that even extensive quantitative compensation in parental effort
by solitary females may not be enough to ensure adequate qualitative compensation for the lack of male participation, highlighting
the importance of distinguishing between these two aspects of compensatory parental care. 相似文献
357.
Carola Borries Tommaso Savini Andreas Koenig 《Behavioral ecology and sociobiology》2011,65(4):685-693
The evolution of social monogamy in larger mammals is difficult to explain because males usually do not invest much in direct
offspring care and might achieve greater fitness by deserting a pregnant female to reproduce with additional females elsewhere.
It has been hypothesized that socially monogamous males remain with the female year-round to protect their offspring from
infanticide by new immigrant males. We investigated this idea by analyzing all cases of infant loss in a wild population of
white-handed gibbons (Hylobates lar; Primates), in which most groups were socially monogamous and some polyandrous (137.5 group years). We examined the influence
of (a) male intruder pressure on male immigration rates and (b) the presence of a new male in the group on infant loss. We
found no relation between intruder pressure and male immigration rates. Infant loss was lowest (4.5%) for stable monogamy
(probable father stayed from conception through infancy) and intermediate (25.0%; p = 0.166) for stable polyandry. If a new male immigrated after conception, however, the infant was lost in all cases (p < 0.01) independent of the presumed father’s presence. Overall, 83.3% of infant losses were associated with the presence
of a presumably unrelated male. Although the sample size is small, our results provide the first true support for the idea
that the risk of infanticide is an important factor in the evolution of social monogamy in larger mammals. 相似文献
358.
Patricia Belinda Crosby Forbes Andreas Tr��e Egmont R. Rohwer 《Environmental Chemistry Letters》2011,9(1):7-12
Rapid methods are needed to analyse air pollutants such as polycyclic aromatic hydrocarbons (PAHs). Reliable semi-quantitative
gas standards were required for the development of a laser-induced fluorescence (LIF) method for polycyclic aromatic hydrocarbon
analysis, based on sampling of air onto multi-channel polydimethylsiloxane rubber traps. Easily constructed diffusion tubes
provided naphthalene vapour at ~2 ng s−1. A gas chromatographic fraction collection method for loading less volatile PAHs onto the traps from a flame ionization detector
outlet was developed and optimized. The accuracy of the method, which can be further optimized, was sufficient for initial
LIF screening tests to flag samples exceeding threshold PAH levels for subsequent quantitative GC–MS analysis. 相似文献
359.
A new approach to investigate the interactions between sediment transport and ecotoxicological processes during flood events 总被引:1,自引:0,他引:1
Holger Schüttrumpf Markus Brinkmann Catrina Cofalla Roy M Frings Sabine U Gerbersdorf Markus Hecker Sebastian Hudjetz Ulrike Kammann Gottfried Lennartz Sebastian Roger Andreas Schäffer Henner Hollert 《Environmental Sciences Europe》2011,23(1):1-5
Purpose
The 'step-by step' principle was introduced into the European Union legislation on genetically modified organisms as a means to cope with uncertainty about environmental risks from the release of genetically modified organisms into the environment. The approval process is orientated along the stepwise reduction of containment which reflects a precautionary approach towards the risks of genetically modified organism release. Thus, the gradual reduction of containment should keep pace with the gradual generation of risk-related knowledge. This paper strives to clarify the meaning, legal status and practical importance of the principle. It also looks at whether non-European Union countries have adopted the principle as well, and how they practice it.Methods
The article is based on research of the relevant legal texts, court cases and legal literature. In addition, a number of dossiers of applications for the European Union authorisation of release and placing on the market of genetically modified seed were analysed.Results and conclusions
Although 'step-by-step' is not a precise legal rule it does have legal meaning as a principle guiding the risk assessment and management of genetically modified organism introduction into the environment. Assuming a process of gradual reduction of containment and scaling up of release ranging from closed systems via experimental release to cultivation the 'step-by-step principle' requires that the knowledge on environmental risks of genetically modified organisms should be generated on stages previous to the ones where the risk can result in damage. The analysis of the legislation of China, the United States of America and Brazil showed a differentiated approach towards the step-by-step principle. 相似文献360.
Andreas Dufke Thomas Eggermann Karl Oliver Kagan Markus Hoopmann Miriam Elbracht 《黑龙江环境通报》2023,43(8):983-992
Imprinting Disorders (ImpDis) are a group of congenital conditions caused by aberrant imprinting resulting in disturbed expression of parentally imprinted genes. ImpDis are rarely associated with major malformations, but pre- and/or postnatal growth and nutrition are often affected. In some ImpDis, behavioral, developmental, metabolic and neurological symptoms might present in the perinatal context or later in life, and in single ImpDis, there is a higher risk of tumors in childhood. Prognosis depends in part on the molecular cause of each ImpDis, but due to high clinical variability and (epi)genetic mosaicism, predicting the clinical outcome of a pregnancy solely based on the underlying molecular disturbance is difficult. Therefore, interdisciplinary care and treatment approaches play an important role in the management and decision making of affected pregnancies, especially taking into account fetal imaging in addition to genetic findings. Prenatal findings influence perinatal management, and thereby improve the prognosis of ImpDis associated with severe but sometimes transient clinical complications in the neonatal period. Therefore, prenatal diagnosis can be crucial for appropriate management not only to the pregnancy itself but might also have a life-long effect. 相似文献