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181.
Michael Heym Ricardo Ruíz-Peinado Miren Del Río Kamil Bielak David I. Forrester Gerald Dirnberger Ignacio Barbeito Gediminas Brazaitis Indrė Ruškytkė Lluís Coll Marek Fabrika Lars Drössler Magnus Löf Hubert Sterba Václav Hurt Viktor Kurylyak Fabio Lombardi Dejan Stojanović Jan Den Ouden Renzo Motta Maciej Pach Jerzy Skrzyszewski Quentin Ponette Géraud De Streel Vit Sramek Tomáš Čihák Tzvetan M. Zlatanov Admir Avdagic Christian Ammer Kris Verheyen Buraczyk Włodzimierz Andrés Bravo-Oviedo Hans Pretzsch 《Annals of Forest Science》2017,74(3):63
Key message
This data set provides unique empirical data from triplets of Scots pine ( Pinus sylvestris L.) and European beech ( Fagus sylvatica L.) across Europe. Dendrometric variables are provided for 32 triplets, 96 plots, 7555 trees and 4695 core samples. These data contribute to our understanding of mixed stand dynamics. Dataset access at http://dx.doi.org/10.5061/dryad.8v04m . Associated metadata available at https://metadata-afs.nancy.inra.fr/geonetwork/apps/georchestra/?uuid=b3e098ca-e681-4910-9099-0e25d3b4cd52&hl=eng .182.
Linda A. Deegan Amos Wright Suzanne G. Ayvazian John T. Finn Heidi Golden Rebeka Rand Merson John Harrison 《水产资源保护:海洋与淡水生态系统》2002,12(2):193-212
- 1. Anthropogenic‐derived nutrient inputs to coastal environments have increased dramatically worldwide in the latter half of the 20th century and are altering coastal ecosystems. We evaluated the effects of nitrogen loading on changes in macrophyte community structure and the associated fauna of a north temperate estuary. We found that a shift in primary producers from eelgrass to macroalgae in response to increased nutrient loading alters habitat physical and chemical structure and food webs. As nitrogen load increased we found increased macroalgal biomass, decreased eelgrass shoot density and biomass, decreased fish and decapod abundance and biomass, and decreased fish diversity.
- 2. The central importance of macroalgae in altering eelgrass ecosystem support of higher trophic levels is evident in the response of the ecosystem when this component was manipulated. Removal of macroalgae increased eelgrass abundance and water column and benthic boundary layer O2 concentrations. These changes in the physical and chemical structure of the ecosystem with lower macroalgal biomass resulted in higher fish and decapod abundance and biomass.
- 3. Both a 15N tracer experiment and the growth of fishes indicated that little of the macroalgal production was immediately transferred to secondary consumers. δ15N values indicated that the most abundant fishes were not using a grazing food web based on macroalgae. Fish tended to grow better and have a greater survivorship in eelgrass compared to macroalgal habitats.
- 4. Watershed‐derived nutrient loading has caused increased macroalgal biomass and degradation and loss of eelgrass habitat, thus reducing the capacity of estuaries to support nekton.
183.
The demands for increasing global crop production have prompted the development of new approaches relying on molecular marker
technologies to investigate and improve the plant genome. The merits of molecular markers make them valuable tools in a range
of research areas. This review describes novel approaches based on modern molecular marker technologies for characterization
and utilization of genetic variation for wheat improvement. Large-scale genome characterization by DNA-fingerprinting has
revealed no declining trends in the molecular genetic diversity in wheat as a consequence of modern intensive breeding thus
opposing the genetic ‘erosion’ hypothesis. A great number of important major genes and quantitative trait loci have been mapped
with molecular markers. Marker-assisted selection based on a tight linkage between a marker allele and a gene(s) governing
a qualitative or quantitative trait is gaining considerable importance as it facilitates and accelerates cultivar improvement
through precise transfer of chromosome regions carrying the gene of interest. The implementations of molecular markers in
wheat genotyping, mapping and breeding complemented by specific approaches associated with the complex polyploid nature of
common wheat are analyzed and presented. 相似文献