Search results for "FOREST"
showing 10 items of 3780 documents
Production of β-glucosidases by European Armillaria species
2020
International audience; Abstract Production of β-glucosidase was investigated in nine isolates of Armillaria representing four species found in Europe: Armillaria mellea and Armillaria ostoyae, considered to be pathogenic and moderately pathogenic, respectively, and Armillaria. gallica and Armillaria cepistipes, both considered to be non-pathogenic. β-glucosidase was predominantly produced in the rhizomorphs, while the vegetative mycelium produced only a low amount of enzyme. Pachlewski's medium containing ammonium tartrate, glucose, maltose and thiamine was very efficient in promoting differentiation and growth of rhizomorphs. In A. ostoyae and A. cepistipes, a large proportion of β-glucos…
Les actions du chlorfenprop-methyl sur l'integrite membranaire dans les mitochondries des plantes
1983
Summary The action of chlorfenprop-methyl, chlorfenprop and its cysteine conjugate was studied on potato tuber mitochondria. Chlorfenprop-methyl altered membrane structure at 250 μM. leading to a loss of membrane integrity. Chlorfenprop and its cysteine conjugate were without any significant effects. From what is known about the rapid hydrolysis of chlorfenprop-methyl in plant tissues and from the results presented in this paper, it was deduced that alteration in intra-cellular membrane integrity is not a mechanism of phytotoxic action for chlorfenprop-methyl. Resume Les actions du chlorfenprop-methyl sur l'integrite membranaire dans les mitochondries des plantes Les actions du chlorfenprop…
New Mediterranean Biodiversity Records (November 2020)
2019
This article includes 23 new records of alien and cryptogenic species in the Mediterranean Sea, belonging to 4 Phyla (Chordata, Echinodermata, Arthropoda and Mollusca), distributed from the Alboran to the Levantine Sea. Records are reported from eight countries listed from West to East as follows: Algeria : new records of the Atlantic blue crab Callinectes sapidus ; Spain : further spread and establishment of the sea slug Lamprohaminoea ovalis in continental shores; Tunisia : first record of the Atlantic Blue Crab Callinectes sapidus in the Gulf of Gabes; Italy : a new occurrence of the pufferfish Lagocephalus sceleratus in Northern Ionian waters; first record of Cephalopholis taeniops in t…
Biogeographical patterns of soil molecular microbial biomass as influenced by soil characteristics and management
2011
Aim The spatial organization of soil microbial communities on large scales and the identification of environmental factors structuring their distribution have been little investigated. The overall objective of this study was to determine the spatial patterning of microbial biomass in soils over a wide extent and to rank the environmental filters most influencing this distribution.
Numerical Study on the Heading Misalignment and Current Velocity Reduction of a Vessel-Shaped Offshore Fish Farm
2019
Recently, the concept of a vessel-shaped fish farm was proposed for open sea applications. The fish farm comprises a vessel-shaped floater, five fish cages, and a single-point mooring system. Such a system weathervanes, and this feature increases the spread area of fish waste. Still, the downstream cages may experience decreased exchange of water flow when the vessel heading is aligned with the current direction, and fish welfare may be jeopardized. To ameliorate the flow conditions, a dynamic positioning (DP) system may be required, and its power consumption should relate to the heading misalignment. This paper proposes an integrated method for predicting the heading misalignment between t…
Chapter 4 Iron Dynamics in the Rhizosphere
2008
Abstract Iron is an essential micronutrient for most organisms due to its role in fundamental metabolic processes. In cultivated soils, soil solution iron is mostly oxidized [Fe(III) species] unless local anoxic conditions develop. The concentration of these Fe(III) species is small in soil solution due to the low solubility of ferric oxides, oxyhydroxides, and hydroxides, which is minimal at neutral and alkaline pH. In the rhizosphere, iron concentration in the soil solution is even lower because of its uptake by aerobic organisms (plants and microorganisms), leading to a high level of competition for Fe(III). In order to face iron competition, these organisms have evolved active uptake st…
The effect of peracetic acid on microbial community, water quality, nitrification and rainbow trout (Oncorhynchus mykiss) performance in recirculatin…
2020
Abstract Microbial biofilters control water quality and enable the overall function of recirculation aquaculture systems (RAS). Changes in environmental conditions can affect the abundance and interactions of the diverse microbial populations of the biofilter, affecting nitrification of harmful ammonium and thus fish health. Here, we examined the effect of different application frequencies (0, 1, 2 and 4 times per week) of a common disinfectant, peracetic acid (PAA, applied 1.1 mg l−1 twice per day), on biofilter microbial communities, focusing especially on nitrifying microbial groups and using a high throughput sequencing of 16S rRNA gene and quantitative PCR (qPCR). In addition, we measu…
Synthesis and influence of fatty acid esters on the foliar penetration of herbicides
1998
Abstract Synthesis of mono-esters of tetraethylene glycol and di-esters of tetraethylene glycol was accomplished from fatty acids and tetraethylene glycol in the absence of solvent and catalyst. Esterification was studied in a batch reactor by using a response surface methodology to evaluate the influence of synthesis variables such as molar substrate ratio of fatty acid relative to tetraethylene glycol (1.39–7.52), temperature (145–167°C), reaction time (0.5–8 h) on the yield of mono- and di-esters of tetraethylene glycol. A multipurpose reactor was developed for the transformation of fatty acids into pure α-monoglycerides. The 1-monoglycerides of heptanoic, undecelenic, oleic, linoleic an…
SOILS AND PLANTS IN AN ANTHROPOGENIC DUMP OF THE KOKDZHON PHOSPHORITE MINE (KAZAKHSTAN)
2017
Soil development is a crucial aspect in the process of mine spoil restoration and is also critical for the establishment of the vegetation. In this short paper, we present the features of mine proto-soils (i.e. soils at the early stage of development) and the natural vegetation species colonizing mine sites in a dry arid environment of Kazakhstan characterized by surface disturbance due to mine activity to access phosphorite deposit. These disturbed soils showed morphological features very different from each other (particularly horizons depth and sequence), even if the main chemical features were quite homogeneous. This is reasonably linked to the features of the Human Transported Material…
Intensified forestry as a climate mitigation measure alters surface water quality in low intensity managed forests
2020
Climate change has led to a focus on forest management techniques to increase carbon (C) sequestration as a mitigation measure. Fertilisation and increased removal of biomass have been proposed. But these and other forest practices may have undesirable effects on surface water quality. In naturally acid-sensitive areas such as much of Fennoscandia a concern is acidification due to acid deposition in combination with forest practices that increase the removal of base cations and leaching of nitrate (NO3). Here we apply the biogeochemical model MAGIC to the coniferous-forested catchment at Birkenes, southernmost Norway, to simulate the effects of forest fertilisation and harvest on soil and s…