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Melissa S. Lucash Robert M. Scheller Eric J. Gustafson Brian R. Sturtevant 《Landscape Ecology》2017,32(5):953-969
Context
Resilience, the ability to recover from disturbance, has risen to the forefront of scientific policy, but is difficult to quantify, particularly in large, forested landscapes subject to disturbances, management, and climate change.Objectives
Our objective was to determine which spatial drivers will control landscape resilience over the next century, given a range of plausible climate projections across north-central Minnesota.Methods
Using a simulation modelling approach, we simulated wind disturbance in a 4.3 million ha forested landscape in north-central Minnesota for 100 years under historic climate and five climate change scenarios, combined with four management scenarios: business as usual (BAU), maximizing economic returns (‘EcoGoods’), maximizing carbon storage (‘EcoServices’), and climate change adaption (‘CCAdapt’). To estimate resilience, we examined sites where simulated windstorms removed >70% of the biomass and measured the difference in biomass and species composition after 50 years.Results
Climate change lowered resilience, though there was wide variation among climate change scenarios. Resilience was explained more by spatial variation in soils than climate. We found that BAU, EcoGoods and EcoServices harvest scenarios were very similar; CCAdapt was the only scenario that demonstrated consistently higher resilience under climate change. Although we expected spatial patterns of resilience to follow ownership patterns, it was contingent upon whether lands were actively managed.Conclusions
Our results demonstrate that resilience may be lower under climate change and that the effects of climate change could overwhelm current management practices. Only a substantial shift in simulated forest practices was successful in promoting resilience.2.
3.
Peptide processing and targeting in the neuronal secretory pathway 总被引：14，自引：0，他引：14
The abdominal ganglion of the marine mollusk Aplysia contains a pair of identified neuronal clusters, the bag cells, which control egg laying by means of a number of unique regulatory mechanisms. Each neuron in the bag cell clusters synthesizes several peptides derived from a single prohormone and packages them into separate vesicles. These vesicles are then differentially localized in specific neuronal processes, thus segregating peptides destined for autocrine and hormonal release sites. Therefore in this system, protein trafficking through the secretory pathway organizes multiple peptide neurochemical messengers to efficiently regulate simple behaviors. 相似文献
4.
Katz HE Scheller G Putvinski TM Schilling ML Wilson WL Chidsey CE 《Science (New York, N.Y.)》1991,254(5037):1485-1487
Polar orientation of molecules in solids leads to materials with potentially useful properties such as nonlinear optical and electrooptical activity, electrochromism, and pyroelectricity. A simple self-assembly procedure for preparing such materials is introduced that yields multiple polar dye monolayers on solid surfaces joined by zirconium phosphate-phosphonate interlayers. Second harmonic generation (SHG) shows that the multilayers have polar order that does not decrease with increasing numbers (up to a large number) of monolayers in the film. The inorganic interlayers, as determined by SHG, impart excellent orientational stability to the dye molecules, with the onset of orientational randomization above 150 degrees C. 相似文献
5.
Egg-laying behavior in Aplysia is mediated by a set of peptides, including egg-laying hormone (ELH), which are released by a cluster of identified neurons, the bag cells. A family of neuropeptide genes which includes the gene encoding ELH along with two additional genes encoding the A and B peptides thought to initiate the egg-laying process has been isolated and their nucleotide sequence has been determined. In situ hybridization and immunofluorescence was used to explore the origin and distribution of the neurons that express this family of genes. The ELH genes are expressed, not only in the bag cells, but in an extensive system of neurons distributed in four of the five ganglia of the central nervous system. The genes for ELH are expressed in these cells early in the animal's life cycle. As a result, it was possible to use in situ hybridization to trace the cells expressing ELH to their site of origin. The cells originate outside the central nervous system in the ectoderm of the body wall and appear to migrate to their final locations within the central nervous system by crawling along strands of connective tissue. 相似文献
6.
H. -D. v. Scheller 《Journal of pest science》1961,34(2):29-29
Ohne Zusammenfassung 相似文献
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Ohne Zusammenfassung 相似文献
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R N Arnold K K Scheller S C Arp S N Williams D R Buege D M Schaefer 《Journal of animal science》1992,70(10):3055-3065
Three experiments were conducted to examine the effects of vitamin E supplementation on feedlot cattle. Vitamin E supplementation did not affect feedlot performance or carcass characteristics of cattle fed a high-concentrate diet (P greater than .1). The major finding was the effectiveness of vitamin E in extending the color stability of displayed beef (P less than .01). Color stability during display of longissimus lumborum steaks from cattle supplemented with 300 IU/d for 266 d, 1,140 IU/d for 67 d, or 1,200 IU/d for 38 d was extended by 2.5 to 4.8 d. Gluteus medius steaks had an extended color display life of 1.6 to 3.8 d. The accumulation of lipid oxidation products, but not aerobic microbes, associated with displayed longissimus lumborum was suppressed for muscle from vitamin E-supplemented steers. Taste panelists detected no difference among longissimus lumborum steaks from control and vitamin E-supplemented steers but found (P less than .01) steaks aged for 21 d to be more tender than steaks aged for 7 d. Supplementing cattle with vitamin E should reduce economic losses associated with discolored beef during retail display. 相似文献
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Untersuchungen in Futterbaubetrieben mit sandigen Ackerböden und Grünland auf Niedermoor ließen einen Einfluss von Fütterungsregime und Grundfutterqualität auf die N‐Bilanzen mit entsprechenden N‐Überschüssen nachweisen. Normgerechte Futterrationen mit einem hohen Anteil an qualitativ hochwertigem Grundfutter reduzierten die N‐Überschüsse. Punktuelle N‐Überschüsse beim Fütterungsregime zur Winteraußenhaltung konnten durch Einstreu reduziert werden. 相似文献