|
|
|
Registros recuperados: 13 | |
|
|
Luoma, S. |
It has been established that direct uptake of (at least some) trace metals from sediments contributes to metal concentrations in benthic organisms. Important controls on metal uptake from sediment are the concentration of the exposure, the partitioning of the metals among components of the sediment, and the redox potential of the sediment. Important problems in ecology, physiology, geochemistry and biogeochemistry remain unresolved, however, and a concentrated interdisciplinary research effort will be necessary before a complete understanding of the fate and impact of sediment-bound metals will be possible. |
Tipo: Text |
Palavras-chave: Bioaccumulation; Benthos; Food webs; Biogeochemical cycle; Sediments; Availability; Trace metals. |
Ano: 1985 |
URL: http://archimer.ifremer.fr/doc/1985/acte-1302.pdf |
| |
|
| |
|
| |
|
| |
|
| |
|
|
Flueck, Werner T.; National Council for Scientific and Technical Research (CONICET), Argentina; Institute of Natural Resources Analysis, Universidad Atlantida Argentina; Swiss Tropical Institute, University of Basel; wtf@deerlab.org. |
The exploitation of natural resources such as forests leads to sustainable forest management (SFM). The key question is how to define and parametrize “sustainable use.” Promoting forest use that conserves spatial characteristics of forest landscapes and the structure and composition of forest stands was proposed as a way of maintaining elements of biodiversity such as species richness and genetic variation. However, to establish the parameter space for sustainable forest use, it is essential to consider the nutrient requirements of forest systems, that is, plants and animals, the need for fertilizer application, and the effects on biogeochemical cycles, a cornerstone of biological evolution and, thus, biodiversity. The use of forest... |
Tipo: Peer-Reviewed Response |
Palavras-chave: Biogeochemical cycle; Fertilizer; Macronutrients; Micronutrients; Phosphorus; Selenium; Sustainable forest management. |
Ano: 2009 |
|
| |
|
|
Mensi, F.; Ksouri, J.; Hammami, W.; Romdhane, M.S.. |
L'algue rouge, Gracilaria verrucosa, a été cultivée, durant le printemps 2009, en mode suspendu à différents emplacements et profondeurs représentant les différences biogéochimiques de la lagune de Bizerte au Nord de la Tunisie. La concentration et la distribution des nutriments (ammonium, phosphate) dans l'eau, ainsi que la salinité, la température, l’oxygène et la transparence de l’eau ont été déterminées. Les méthodes analytiques internationales standardisées ont été appliquées. Les effets du mode de culture, de l’emplacement et de la profondeur sur les rendements en poids, protéines, R-Phycoérythrine et sucres totaux de l’algue ont été étudiés. La croissance de Gracilaria a été similaire dans les différents sites mais plus lente dans les profondeurs... |
Tipo: Journal Contribution |
Palavras-chave: Algal culture; Ammonium compounds; Biochemical composition; Biogeochemistry; Carbohydrates; Dissolved oxygen; Environmental conditions; Growth; Intensive culture; Lagoons; Off-bottom culture; Raw materials; Red algae; Biogeochemical cycle. |
Ano: 2009 |
URL: http://hdl.handle.net/1834/4497 |
| |
|
| |
|
| |
|
|
Alves, Allyson Rocha; Ferreira, Rinaldo Luiz Caraciolo; da Silva, José Antônio Aleixo; Dubeux Júnior, José Carlos Batista; Salami, Gabriela. |
This study aimed to quantify nutrient content in shoot biomass components and litter in two areas of savanna vegetation with different ecological characteristics, one in regeneration and the other as a preserved area, in Floresta, Pernambuco State, Brazil. It was carried out an initial inventory launching 40 plots of 400 m2 in each area, with inclusion level of circumference at 1.3 m above ground level ≥ 6.0 cm. The five species with highest importance value were used for biomass analysis. Chemical analysis were carried out in samples of 100 g taken from the different component of each of those species. To estimate the stock of litter assortments were made in dry and rainy seasons, using a hollow square mold with 0.5 m randomly released in plots. It was... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Biogeochemical cycle; Regeneration; Dry forest Recursos Florestais; Engenharia Florestal Ciclo biogeoquímico; Regeneração; Floresta seca. |
Ano: 2017 |
URL: http://pfb.cnpf.embrapa.br/pfb/index.php/pfb/article/view/1060 |
| |
|
|
Plus, Martin; Auby, Isabelle; Maurer, Daniele; Trut, Gilles; Del Amo, Y.; Dumas, Franck; Thouvenin, Benedicte. |
This study presents an assessment of the contributions of various primary producers to the global annual production and N/P cycles of a coastal system, namely the Arcachon Bay, by means of a numerical model. This 3D model fully couples hydrodynamic with ecological processes and simulates nitrogen, silicon and phosphorus cycles as well as phytoplankton, macroalgae and seagrasses. Total annual production rates for the different components were calculated for different years (2005, 2007 and 2009) during a time period of drastic reduction in seagrass beds since 2005. The total demand of nitrogen and phosphorus was also calculated and discussed with regards to the riverine inputs. Moreover, this study presents the first estimation of particulate organic carbon... |
Tipo: Text |
Palavras-chave: Primary production; Macrophyte; Phytoplankton; Biogeochemical cycle; Physical-ecological coupled model; Arcachon bay. |
Ano: 2015 |
URL: http://archimer.ifremer.fr/doc/00278/38963/37503.pdf |
| |
|
| |
Registros recuperados: 13 | |
|
|
|