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291.
European Journal of Forest Research - Climate-adaptive forest management aims to sustain the provision of multiple forest ecosystem services and biodiversity (ESB). However, it remains largely...  相似文献   
292.
The marine environment represents a largely untapped source for isolation of new microorganisms with potential to produce biologically active secondary metabolites. Among such microorganisms, Gram-positive actinomycete bacteria are of special interest, since they are known to produce chemically diverse compounds with a wide range of biological activities. We have set out to isolate and characterize actinomycete bacteria from the sediments in one of the largest Norwegian fjords, the Trondheim fjord, with respect to diversity and antibiotic-producing potential. Approximately 3,200 actinomycete bacteria were isolated using four different agar media from the sediment samples collected at different locations and depths (4.5 to 450 m). Grouping of the isolates first according to the morphology followed by characterization of isolates chosen as group representatives by molecular taxonomy revealed that Micromonospora was the dominating actinomycete genus isolated from the sediments. The deep water sediments contained a higher relative amount of Micromonospora compared to the shallow water samples. Nine percent of the isolates clearly required sea water for normal growth, suggesting that these strains represent obligate marine organisms. Extensive screening of the extracts from all collected isolates for antibacterial and antifungal activities revealed strong antibiotic-producing potential among them. The latter implies that actinomycetes from marine sediments in Norwegian fjords can be potential sources for the discovery of novel anti-infective agents.  相似文献   
293.
Projections of indicators of forest ecosystem goods and services (EGS) based on process-based landscape models are critical for adapting forest management to climate change. However, the scarcity of fine-grained, spatially explicit forest data means that initializing these models is both a challenge and a source of uncertainty. To test how different initialization approaches influence the simulation of forest dynamics and EGS indicators we initialized the forest landscape model LandClim with fine resolution empirical data, coarse empirical data, and simulation-derived data, and evaluated the results at three spatial scales (stand, management area and landscape). Simulations were performed for a spruce (Picea abies) dominated landscape in the Black Forest, Germany, under current climate and a climate change scenario. We found that long-term (>150 years) projections are robust to initialization uncertainty. In contrast, shorter-term projections are sensitive to initialization uncertainty, with sensitivity increasing when EGS are assessed at smaller spatial scales, and when the EGS indicators depend on the spatial distribution of individual species. EGS dynamics are strongly influenced by interactions between the density, species composition, and age structure of initialized forests and simulated forest management. If EGS dynamics are strongly influenced by climate change, such as when climate change induces mortality in drought-sensitive species, some of the initialization uncertainty can be masked. We advocate for initializing landscape models with fine-grained data in applications that focus on spatial management problems in heterogeneous landscapes, and stress that the scale of analysis must be in accordance with the accuracy that is warranted by the initialization data.  相似文献   
294.
The major by-product from the production of pea protein concentrate is pea starch, and this starch can be an alternative source of starch compared to for instance starch from wheat in diets for pigs. However, differences in energy utilization between pea starch and cereal starch could affect the animals' production performance. In this study data from 100 Norwegian Landrace x Yorkshire sows was collected to investigate if inclusion of 20% pea starch meal (Pisum sativum L) in diets for lactating sows affected sow and litter performance. Two cereal grain based diets were formulated, but in one of the diets part of the wheat inclusion was replaced with pea starch meal. Data collection included registrations of sow daily feed consumption, individual weight and backfat measures, litter weights, measurement of blood glucose level after feeding and reproductive performance. Sows offered the pea diet had a higher average daily (P<0.0001), weekly (P<0.01) and total feed consumption (P<0.0001) during lactation. They also had a lower weight loss during the first three weeks of lactation (P<0.001). During the last two weeks of lactation sows in both groups were on average gaining weight, but the sows offered the control diet had the highest gain in this period (P<0.05). There was a tendency for a higher backfat loss in the pea group during the first three weeks of lactation (P=0.10), but no difference was found in overall backfat loss between treatments (P>0.05). Dietary treatment did not affect litter performance during lactation (P>0.05). The weaning-to-service interval was higher among the first parity sows offered the pea diet compared to the first parity sows offered the control diet (P<0.05). Blood glucose was not affected by dietary treatment within the chosen timeframe of this study (P>0.05). This study shows that pea starch meal can be used as an alternative source of starch in diets for lactating sows. The sows offered the pea diet had the highest feed consumption during lactation, and although this was not reflected in higher weaning weights, it was reflected in an improved body condition at weaning.  相似文献   
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