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41.
Economic reasons for conserving wild nature 总被引：2，自引：0，他引：2
Balmford A Bruner A Cooper P Costanza R Farber S Green RE Jenkins M Jefferiss P Jessamy V Madden J Munro K Myers N Naeem S Paavola J Rayment M Rosendo S Roughgarden J Trumper K Turner RK 《Science (New York, N.Y.)》2002,297(5583):950-953
On the eve of the World Summit on Sustainable Development, it is timely to assess progress over the 10 years since its predecessor in Rio de Janeiro. Loss and degradation of remaining natural habitats has continued largely unabated. However, evidence has been accumulating that such systems generate marked economic benefits, which the available data suggest exceed those obtained from continued habitat conversion. We estimate that the overall benefit:cost ratio of an effective global program for the conservation of remaining wild nature is at least 100:1. 相似文献
42.
Anu K Lappalainen Elina Vaittinen Jouni Junnila Outi Laitinen-Vapaavuori 《Acta veterinaria Scandinavica》2014,56(1)
Background
Intervertebral disc disease (IDD) is a very common neurological disease, Dachshunds being the breed most often affected. In this breed, IDD has a hereditary background and is associated with intervertebral disc calcification (IDC), an indicator of severe intervertebral disc degeneration. In Finland, spinal radiography is used, when screening for IDC before breeding Dachshunds. We evaluated the association between IDC and IDD in Finnish Dachshunds radiographically screened for IDC.A questionnaire was sent to owners of 193 radiographically screened Dachshunds aged at least ten years. Clinical signs indicative of IDD were compared with IDC grade (grade 0 = no calcifications, grade 1 = 1 – 2 calcifications, grade 2 = 3 – 4 calcifications and grade 3 = 5 or more calcifications) and with age at the time of the radiographic examination. The diagnosis of IDD was confirmed by a veterinarian.Results
IDD was common in the study population with 31% of dogs being affected. IDD and IDC were clearly connected (P < 0.001); IDD was rare in dogs with no calcifications (grade 0) and common in dogs with severe IDC (grade 3). The IDC grade was strongly positively associated with frequency of back pain periods (P < 0.001), and dogs with IDC grade 3 had frequent periods of pain. Reluctance to jump onto a sofa had a strong positive association with back pain. No association existed between age of the dog at the time of the radiographic examination and clinical signs indicative of IDD.Conclusions
Radiographically detected IDC and IDD are common in Finnish Dachshunds and are strongly associated with one another. Spinal radiography is an appropriate screening tool for breeders attempting to diminish IDC and IDD in Dachshunds. A breeding program that screens dogs and selects against IDC can be expected to reduce the occurrence of IDD in future. Twenty-four to 48 months of age is a suitable age for screening.Electronic supplementary material
The online version of this article (doi:10.1186/s13028-014-0089-4) contains supplementary material, which is available to authorized users. 相似文献43.
Liwei Liu Lars Herfindal Jouni Jokela Tania Keiko Shishido Matti Wahlsten Stein Ove D?skeland Kaarina Sivonen 《Marine drugs》2014,12(4):2036-2053
In this study, we investigated forty cyanobacterial isolates from biofilms, gastropods, brackish water and symbiotic lichen habitats. Their aqueous and organic extracts were used to screen for apoptosis-inducing activity against acute myeloid leukemia cells. A total of 28 extracts showed cytotoxicity against rat acute myeloid leukemia (IPC-81) cells. The design of the screen made it possible to eliminate known toxins, such as microcystins and nodularin, or known metabolites with anti-leukemic activity, such as adenosine and its analogs. A cytotoxicity test on human embryonic kidney (HEK293T) fibroblasts indicated that 21 of the 28 extracts containing anti-acute myeloid leukemia (AML) activity showed selectivity in favor of leukemia cells. Extracts L26-O and L30-O were able to partly overcome the chemotherapy resistance induced by the oncogenic protein Bcl-2, whereas extract L1-O overcame protection from the deletion of the tumor suppressor protein p53. In conclusion, cyanobacteria are a prolific resource for anti-leukemia compounds that have potential for pharmaceutical applications. Based on the variety of cellular responses, we also conclude that the different anti-leukemic compounds in the cyanobacterial extracts target different elements of the death machinery of mammalian cells. 相似文献
44.
Trophic-dynamic hypotheses have been extensively tested by manipulating the presence of soil animals in experimental laboratory microcosms. Soil animals typically have pronounced effects on microbial populations, nutrient cycling and plant growth. However, because often only the total effect has been reported, the relative importance of feeding interactions versus non-trophic effects remains obscure. Using simple calculations based on mass conservation I argue that the observed faunal effect on microbes and system functioning is often larger than can be explained by trophic dynamics and nutrient cycling. Non-trophic effects may help to explain why microcosm experiments have failed to support trophic-dynamic predictions like trophic cascades. Since such effects are also likely independent of species identity and population density, they may facilitate the interpretation of experiments where decomposition processes have been found to be largely insensitive to soil fauna diversity. 相似文献
45.
Uchechukwu Enyidi Mikko Kiljunen Roger I. Jones Juhani Pirhonen Jouni Vielma 《Journal of the World Aquaculture Society》2013,44(2):161-172
Knowledge of ingredients assimilation and biomass contribution to recipient fish is important in feed formulation. The stable isotopes of 13C and 15N were used to investigate the assimilation and biomass contribution of bambaranut, Voandzeia subterranea, meal (BNM), corn, Zea mays, meal (CM) and fish meal (FM), in FM substituted diets of first feeding African catfish, Clarias gariepinus, during a 30‐d experiment. The catfish larvae were stocked at 40 fish/15 L three replicate glass aquaria. Larvae were fed with experimental diets varying FM, BNM, and CM. Proportions of FM : BNM : CM in the experimental diets were: feed 1 (F1) 60:20:20; feed 2 (F2) 40:40:20; feed 3 (F3) 20:60:20; and feed 4 (F4) 20:20:60. Feeds and larval stable isotopes of δ13C and δ15N were analyzed. Larval specific growth rates (SGRs) were high, enhancing incorporation of dietary δ13C and δ15N. The SGR was highest for catfish fed F1 and F2 but significantly lower for those on F3 and F4. Results of δ13C and δ15N analyses showed that the biomass contribution from FM was similar to BNM, which were better than CM at equal inclusion levels. The nitrogen contribution per ingredient to larval somatic crude protein was increasing with increases in ingredient inclusion and assimilation. Stable isotope analysis is useful for analyzing assimilation and utilization of nutrients. 相似文献
46.
Digestibility of microbial and mussel meal for Arctic charr (Salvelinus alpinus) and Eurasian perch (Perca fluviatilis) 
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下载免费PDF全文 M. Langeland A. Vidakovic J. Vielma J.E. Lindberg A. Kiessling T. Lundh 《Aquaculture Nutrition》2016,22(2):485-495
Apparent digestibility coefficients (ADCs) for four protein‐rich alternative feed ingredients, intact baker's yeast (Saccharomyces cerevisiae), extracted baker's yeast (S. cerevisiae), zygomycetes (Rhizopus oryzae) and blue mussel (Mytilus edulis), were determined for Arctic charr (Salvelinus alpinus) and Eurasian perch (Perca fluviatilis). Diets contained 30% of test ingredients, and ADCs were compared to a reference diet containing fish meal. For Arctic charr, ADCs for dry matter (DM, 71–99%), sum of amino acids (SAA, 84–99%) and gross energy (70–99%) were significantly lower for intact S. cerevisiae than for extracted S. cerevisiae, R. oryzae and M. edulis. The ADCs for the indispensable amino acids (IAA) in Arctic charr varied between 84% and 99%. Significant differences were found in ADCs for IAA between the test ingredients for Arctic charr, with higher values for extracted S. cerevisiae and M. edulis. The ADCs in Eurasian perch varied between 83% and 95% for DM, 89% and 98% for CP, 92% and 100% for SAA, 81% and 96% for gross energy. No significant differences were found for ADCs between the test ingredients in Eurasian perch, indicating a species effect on digestibility. Furthermore, the absence of intact cell walls had a positive effect on digestibility of S. cerevisiae for Arctic charr. 相似文献
47.
Veikko Hiltunen Mikko Kurttila Pekka Leskinen Karri Pasanen Jouni Pykäläinen 《Forest Policy and Economics》2009,11(1):1-9
We tested the Mesta Internet-based decision-support application in connection with a natural resources planning (NRP) process in Eastern and Western Lapland, Finland. The aim in this process was to define the land-use allocation and the corresponding forest management operations for state-owned forests within these planning regions. Mesta was used in examining and evaluating the strategy alternatives from the viewpoint of the stakeholders' objectives. The basic idea in using Mesta is to define the acceptance thresholds that divide the alternatives into ‘acceptable’ and ‘not acceptable’ alternatives with respect to each decision criterion. The thresholds are adjusted holistically, i.e. so that all decision criteria and criteria values of all decision alternatives are simultaneously visible from the user interface. The holistic adjustment process is continued until an acceptable solution compliant with the production possibilities of the planning area is found. In the NRP process, the members of the stakeholder group first used Mesta individually to set their own thresholds. Next, the participants' acceptance thresholds were combined and a negotiation process was launched to find the group's common acceptance thresholds. This negotiation was also supported by Mesta. The result of the negotiation was that the participants were able to collaboratively decide on their recommendation for the future land-use allocation and the forest management principles to be applied in the two planning regions. The main benefit of Mesta as a decision-support tool during the negotiation process of the group was that the participants were forced to merge their preferences with the realistic production possibilities of the planning regions. 相似文献
48.
Mikko Kurttila Eero Muinonen Pekka Leskinen Harri Kilpeläinen Jouni Pykäläinen 《European Journal of Forest Research》2009,128(1):37-50
A proper forest planning process includes the assessment of the decision-makers’ preferences concerning the future forest
use. For some owners, it may be a difficult task to express their preferences exactly and in the form that is required for
planning calculations. This study presents a new kind of approach for analyzing the effects of preferential uncertainty. The
approach consists of examination of the differences in the actual decision variables in forest planning, i.e. selected treatments
for stands between holding-level forest plans. In example calculations, the preferential uncertainty was examined from three
different viewpoints: the uncertainty in the weights of the objective variables; the uncertainty in the partial utility function;
and the combination of these two uncertainty sources. One thousand preference realizations were generated for each of these
uncertainty sources. More than one treatment schedules are proposed for stands that are affected by preferential uncertainty.
These stands were detected from among the resulting set of 1,000 forest plans. With this done, two potential decision-making
strategies, an adaptive behavior strategy and a threshold proportion strategy, were applied as guides in decision-making for
stands, which have more than one treatment alternative selected in the produced optimal forest plans. The adaptive behavior
technique required that the forest owner select one treatment alternative for at least one stand that has more than one proposed
treatment alternative. The treatment alternatives having frequencies exceeding the given threshold frequency were all accepted
simultaneously in the threshold strategy. The main benefit of the approach is to present the effects of uncertainties in a
way that can be easily understood by the actual decision-makers. It is a promising tool for practical decision-making situations
because at least Finnish non-industrial private forest owners quite often focus on making stand-level forest management decisions.
It is also suitable for examinations of other uncertainty sources such as timber prices or inventory data. 相似文献
49.
Voluntary biodiversity protection tools have been adopted for practical use in many countries where non-industrial private
forest ownership includes invaluable biodiversity resources. This has created a new kind of decision problem for individual
forest owners: they should be able to define their conditions for entering into a biodiversity protection contract including
sometimes a predetermined subsidy. This study presents a holding-level method for examining this decision problem. The method
is based on utilization of interactive optimization where the possible subsidy has been included in the protection (no treatment)
alternative of the examined stand. Generally, interactive optimization means that the landowner pinpoints the best plan by
interactively studying and learning the production possibilities of his/her forest holding. Following changes made to the
objective function by the forest owner, new solutions are presented for forest owners’ evaluation. If the “No treatments”
option is selected in optimization for these areas, the forest owner would benefit more—in the current location of the production
frontier and with the current subsidy—from entering into the protection contract than from cutting the specific forest area.
In the case study, we demonstrate that the values of the holding-level goals, production possibilities of the planning area
and the levels of the subsidy have a significant effect on the optimal decisions relating to biodiversity protection on the
stand level. 相似文献
50.
Electrofishing as a new method to search for unknown populations of the endangered freshwater pearl mussel Margaritifera margaritifera 下载免费PDF全文
下载免费PDF全文 1. The freshwater pearl mussel Margaritifera margaritifera is threatened throughout its Holarctic range, but the occurrence of this species is insufficiently mapped. For the conservation of M. margaritifera, it is important to identify populations more comprehensively. 2. Traditionally mussels have been searched for visually using techniques such as diving and aquascope, both of which are potentially time‐consuming and demanding survey methods. 3. In this study, a new search method is presented. As glochidia of M. margaritifera are larval parasites on the gills of salmonid fish, electrofishing and non‐destructive examination of salmonids with the naked eye may reveal the presence of glochidia and therefore the occurrence of M. margaritifera in watercourses. This method was tested in both the field and laboratory in northern Finland. 4. In summer, when M. margaritifera glochidia were large, the status of salmonids being infected or uninfected by M. margaritifera was correctly identified with the naked eye with 62, 80, 88 and 93% accuracy in four streams sampled, 96% accuracy in the laboratory, and 100% accuracy in all cases when at least 20 glochidia per fish were present. Intensity of infection was also assessed successfully; a specifically tailored, qualitative abundance score correlated significantly with the real number of glochidia. However, during autumn with small glochidia freshly attached to fish, glochidia infection could be observed only under microscopic examination. 5. When the method was used in 40 previously incompletely surveyed tributaries, three M. margaritifera populations were found. The infection in salmonids was observed always with the naked eye, being subsequently confirmed microscopically. The existence of adult mussels in two of these rivers was also confirmed. 6. The results indicate that electrofishing and a relatively quick naked‐eye check of salmonids provides a new, non‐destructive, and potentially cost‐effective way to search for new, previously unrecorded M. margaritifera populations. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献