排序方式: 共有23条查询结果,搜索用时 234 毫秒
1.
Linking water market functioning, access to water resources and farm production strategies: example from Pakistan 总被引:3,自引:0,他引:3
Jean-Daniel Rinaudo Pierre Strosser Thierry Rieu 《Irrigation and Drainage Systems》1997,11(3):261-280
As a response to inadequacy in canal water supplies, farmers in Pakistan have invested in private tubewells to control irrigation water resources. Also, they participate in surface water and groundwater markets that take place within tertiary units of the irrigation system.The present paper describes the functioning and organization of these water markets, using information collected in sample watercourses of the Fordwah Branch irrigation system, South-Punjab, Pakistan. The variability in type and intensity of water markets is investigated with regard to access to water resources and farm production strategies and constraints. 相似文献
2.
A simple apparatus was developed to study metabolic gases in the rice rhizosphere. With this device, a positive rhizosphere effect of rice was demonstrated on three soil microbial activities: N2 fixation, CH4 formation and denitrification. 相似文献
3.
Ingrid Seynave Alain Bailly Philippe Balandier Jean-Daniel Bontemps Priscilla Cailly Thomas Cordonnier Christine Deleuze Jean-François Dhôte Christian Ginisty François Lebourgeois Dominique Merzeau Eric Paillassa Sandrine Perret Claudine Richter Céline Meredieu 《Annals of Forest Science》2018,75(2):48
Key message
The diversity of forest management systems and the contrasted competition level treatments applied make the experimental networks of the GIS Coop, a nationwide testing program in the field of emerging forestry topics within the framework of the ongoing global changes.Context
To understand the dynamics of forest management systems and build adapted growth models for new forestry practices, long-term experiment networks remain more crucial than ever.Aims
Two principles are at the basis of the experimental design of the networks of the Scientific Interest Group Cooperative for data on forest tree and stand growth (GIS Coop): contrasted and extreme silvicultural treatments in diverse pedoclimatic contexts.Methods
Various forest management systems are under study: regular and even-aged stands of Douglas fir, sessile and pedunculate oaks, Maritime and Laricio pines, mixed stands of sessile oak, European silver fir, and Douglas fir combined with other species. Highly contrasted stand density regimes, from open growth to self-thinning, are formalized quantitatively.Results
One hundred and eighty-five sites representing a total of 1206 plots have been set up in the last 20 years, where trees are measured regularly (every 3 to 10 years). The major outputs of these networks for research and management are the calibration/validation of growth and yield models and the drawing up of forest management guides.Conclusion
The GIS Coop adapts its networks so that they can contribute to develop growth models that explicitly integrate pedoclimatic factors and thus also contribute to research on the sustainability of ecosystems under environmental and socio-economic changes.4.
Marie Charru Ingrid Seynave Jean-Christophe Hervé Romain Bertrand Jean-Daniel Bontemps 《Annals of Forest Science》2017,74(2):33
Key message
Recent growth changes (1980–2007) in Western European forests strongly vary across tree species, and range from +42% in mountain contexts to ?17% in Mediterranean contexts. These changes reveal recent climate warming footprint and are structured by species' temperature (?) and precipitation (+) growing conditions.Context
Unprecedented climate warming impacts forests extensively, questioning the respective roles of climatic habitats and tree species in forest growth responses. National forest inventories ensure a repeated and spatially systematic monitoring of forests and form a unique contributing data source.Aims
A primary aim of this paper was to estimate recent growth changes in eight major European tree species, in natural contexts ranging from mountain to Mediterranean. A second aim was to explore their association with species’ climatic habitat and contemporary climate change.Methods
Using >315,000 tree increments measured in >25,000 NFI plots, temporal changes in stand basal area increment (BAI) were modelled. Indicators of climate normals and of recent climatic change were correlated to species BAI changes.Results
BAI changes spanned from ?17 to +42% over 1980–2007 across species. BAI strongly increased for mountain species, showed moderate/no increase for generalist and temperate lowland species and declined for Mediterranean species. BAI changes were greater in colder/wetter contexts than in warmer/drier ones where declines were observed. This suggested a role for climate warming, further found more intense in colder contexts and strongly correlated with species BAI changes.Conclusion
The predominant role of climate warming and species climatic habitat in recent growth changes is highlighted in Western Europe. Concern is raised for Mediterranean species, showing growth decreases in a warmer climate with stable precipitation.5.
Tony Franceschini Jean-Daniel Bontemps Pierre Gelhaye Daniel Rittie Jean-Christophe Herve Jean-Claude Gegout Jean-Michel Leban 《Annals of Forest Science》2010,67(8):816-816
– |
• Studies on wood density variations are necessary for estimating the forest carbon pool. Further, they can help predict the
technological properties of wooden end-products. While there have been frequent reports on the relationships between wood
density, cambial age, and ring width, there is little information about the historical trend in wood density for the last
century, particularly in the context of global climate change. 相似文献
6.
Y. Dommergues J. Balandreau G. Rinaudo Pierrette weinhard 《Soil biology & biochemistry》1973,5(1):83-89
Nitrogenase activity estimated in the rhizospheres of rice, maize and different tropical grasses grown under controlled laboratory conditions was shown to depend upon plant species. High nitrogenase activity (2000–6000 nmoles C2H4 h?1 g?1 dry root) occurred in rice rhizosphere, this activity being only 10 times lower than that of symbiotic systems; in the rhizosphere of many other grasses grown in a similar way nitrogenase activity was as low as 10 nmoles C2H4 h?1 g?1 dry root. The influence of soil type on nitrogenase activity was impressive; but the exact nature of the factors implicated could not be established. A rather weak flush of nitrogenase activity in the rhizosphere occurred in the early stage of the plant growth; it was probably due to the exudation of compounds from the seed and lasted 2 or 4 days according to the size of the seed. When the plant entered into its intense photosynthetic phase, the nitrogenase activity gradually increased. When the shoots were severed, nitrogenase activity in the rhizosphere ceased. Nitrogenase activity in the rhizosphere responded greatly to light intensity. Extrapolation of these laboratory findings to the field is discussed. 相似文献
7.
SB Grant JD Saphores DL Feldman AJ Hamilton TD Fletcher PL Cook M Stewardson BF Sanders LA Levin RF Ambrose A Deletic R Brown SC Jiang D Rosso WJ Cooper I Marusic 《Science (New York, N.Y.)》2012,337(6095):681-686
Humans create vast quantities of wastewater through inefficiencies and poor management of water systems. The wasting of water poses sustainability challenges, depletes energy reserves, and undermines human water security and ecosystem health. Here we review emerging approaches for reusing wastewater and minimizing its generation. These complementary options make the most of scarce freshwater resources, serve the varying water needs of both developed and developing countries, and confer a variety of environmental benefits. Their widespread adoption will require changing how freshwater is sourced, used, managed, and priced. 相似文献
8.
9.
Identification of a universal Group B streptococcus vaccine by multiple genome screen 总被引:2,自引:0,他引:2
Maione D Margarit I Rinaudo CD Masignani V Mora M Scarselli M Tettelin H Brettoni C Iacobini ET Rosini R D'Agostino N Miorin L Buccato S Mariani M Galli G Nogarotto R Nardi-Dei V Nardi Dei V Vegni F Fraser C Mancuso G Teti G Madoff LC Paoletti LC Rappuoli R Kasper DL Telford JL Grandi G 《Science (New York, N.Y.)》2005,309(5731):148-150
Group B Streptococcus (GBS) is a multiserotype bacterial pathogen representing a major cause of life-threatening infections in newborns. To develop a broadly protective vaccine, we analyzed the genome sequences of eight GBS isolates and cloned and tested 312 surface proteins as vaccines. Four proteins elicited protection in mice, and their combination proved highly protective against a large panel of strains, including all circulating serotypes. Protection also correlated with antigen accessibility on the bacterial surface and with the induction of opsonophagocytic antibodies. Multigenome analysis and screening described here represent a powerful strategy for identifying potential vaccine candidates against highly variable pathogens. 相似文献
10.
Characterization of white wine mannoproteins 总被引:5,自引:0,他引:5
Gonçalves F Heyraud A de Pinho MN Rinaudo M 《Journal of agricultural and food chemistry》2002,50(21):6097-6101
Mannoproteins, Saccharomyces cerevisiae yeast polysaccharides, play a major role in wine processing and characteristics. A systematic characterization of these polymers in terms of chemical composition and molecular structure is addressed in this study. Mannoproteins were isolated from white wine through a sequence of operations that consisted of nanofiltration for concentration of macromolecules, polysaccharide precipitation with ethanol, and affinity chromatography on concanavalin A. The whole wine mannoproteins present a very broad molecular mass distribution with several populations. Two major populations with very different compositions were separated by size exclusion chromatography. The mannoproteins with higher molecular mass are a mannose homopolymer containing 10.3% protein. The mannoproteins with lower molecular mass consisted of 87.5% of mannose and some other residues and a protein content of 2.5%. The highest molecular weight mannoprotein structure was examined by (1)H and (13)C NMR spectroscopic techniques such as 1-D TOCSY, 2-D COSY, and 2-D HMQC. 相似文献
|