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1.
Interlocked challenges of climate change, biodiversity loss, and land degradation require transformative interventions in the land management and food production sectors to reduce carbon emissions, strengthen adaptive capacity, and increase food security. However, deciding which interventions to pursue and understanding their relative co‐benefits with and trade‐offs against different social and environmental goals have been difficult without comparisons across a range of possible actions. This study examined 40 different options, implemented through land management, value chains, or risk management, for their relative impacts across 18 Nature's Contributions to People (NCPs) and the 17 Sustainable Development Goals (SDGs). We find that a relatively small number of interventions show positive synergies with both SDGs and NCPs with no significant adverse trade‐offs; these include improved cropland management, improved grazing land management, improved livestock management, agroforestry, integrated water management, increased soil organic carbon content, reduced soil erosion, salinization, and compaction, fire management, reduced landslides and hazards, reduced pollution, reduced post‐harvest losses, improved energy use in food systems, and disaster risk management. Several interventions show potentially significant negative impacts on both SDGs and NCPs; these include bioenergy and bioenergy with carbon capture and storage, afforestation, and some risk sharing measures, like commercial crop insurance. Our results demonstrate that a better understanding of co‐benefits and trade‐offs of different policy approaches can help decision‐makers choose the more effective, or at the very minimum, more benign interventions for implementation.  相似文献   
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We evaluated the response of the Antarctic soil nematodes Scottnema lindsayae and Plectus antarcticus to various salts (NaCl, MgSO4, KNO3 and NaCl + MgSO4) and salt concentrations in prepared salt solutions ranging from 0.1 to 3 M, and in saturation paste extracts of soils collected from multiple locations where nematode abundance varied from zero to numerous, and where electrical conductivity ranged from 108 to >12,000 μS/cm. Nematode salt tolerance was salt specific; both nematode species survived in low-experimental concentrations of NaCl and MgSO4, and neither species survived in KNO3 solutions of any concentration. There was no survival of nematodes in the saturation paste extracts of highly saline soils (4,100 μS/cm), while survival was over 80–97% in less saline soils (1,945 μS/cm). A 1:1 dilution of these highly saline saturation paste extracts increased S. lindsayae survival to 80%, while survival of P. antarcticus was not observed until dilutions of greater than 200%. The results complement previous studies demonstrating niche partitioning of S. lindsayae and P. antarcticus across salinity gradients and strengthen interpretations of the physiological mechanisms underlying previously reported spatial correlation between soil salinity and nematodes abundance in the Antarctic Dry Valleys.  相似文献   
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Plant Molecular Biology Reporter - Sixty-six accessions of Musa genus with different genomic groups that consisted of wild relatives and cultivated lines were obtained from the International...  相似文献   
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Dispersal of soil organisms is crucial for their spatial distribution and adaptation to the prevailing conditions of the Antarctic Dry Valleys. This study investigated the possibility of wind dispersal of soil invertebrates within the dry valleys. Soil invertebrates were evaluated in (1) pockets of transported sediments to lake ice and glacier surfaces, (2) wind-transported dust particles in collection pans (Bundt pans) 100 cm above the soil surface, and (3) sediments transported closer to the surface (<50 cm) and collected in open top chambers (OTCs). Invertebrates were extracted and identified. Nematodes were identified to species and classified according to life stage and sex. Three species of nematodes were recovered and Scottnema lindsayae was the most dominant. There were more juveniles (∼71%) in the transported sediments than adults (29%). Tardigrades and rotifers were more abundant in sediments on lake and glacier surfaces while nematodes were more abundant in the dry sediment collections of Bundt pans and OTCs. The abundance of immobile (dead) nematodes in the Bundt pans and OTCs was three times greater than active (live) nematodes. Anhydrobiosis constitutes a survival mechanism that allows wind dispersal of nematodes in the McMurdo Dry Valleys. Our results show that soil invertebrates are dispersed by wind in the Dry Valleys and are viable in ice communities on lake surfaces and glaciers.  相似文献   
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In this article, we review the fundamental phenomenon of oxygenation within the overriding context of petroleum-industry effluents and the other oxygen demanding wastes in Niger Delta, Nigeria. Drill cuttings, drilling mud (fluids used to stimulate the production processes), and accidental discharges of crude petroleum constitute serious land and water pollution in the oil-bearing province. Effluents from other industrial establishments such as distilleries, pulp and paper mills, fertilizer plants, and breweries, as well as thermal effluents, plant nutrients (such as nitrates and phosphates), and eroded sediments have also contributed to the pollution of their surrounding environment. Since these wastes are oxygen-demanding in nature, their impact on the recipient environment can be reversed by the direct application of simple chemistry. The wastes can be reduced, particularly in natural bodies of water, by direct oxidation-reduction processes or simple chemical combinations, acid-base reactions, and solubility equilibria; these are pH- and temperature-dependent. A shift in pH and alkalinity affects the solubility equilibria of Na+, Cl-, SO(2-), NO3(-), HCO3(-), and PO4(3-), and other ions and compounds.  相似文献   
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There is a clear need for transformative change in the land management and food production sectors to address the global land challenges of climate change mitigation, climate change adaptation, combatting land degradation and desertification, and delivering food security (referred to hereafter as “land challenges”). We assess the potential for 40 practices to address these land challenges and find that: Nine options deliver medium to large benefits for all four land challenges. A further two options have no global estimates for adaptation, but have medium to large benefits for all other land challenges. Five options have large mitigation potential (>3 Gt CO2eq/year) without adverse impacts on the other land challenges. Five options have moderate mitigation potential, with no adverse impacts on the other land challenges. Sixteen practices have large adaptation potential (>25 million people benefit), without adverse side effects on other land challenges. Most practices can be applied without competing for available land. However, seven options could result in competition for land. A large number of practices do not require dedicated land, including several land management options, all value chain options, and all risk management options. Four options could greatly increase competition for land if applied at a large scale, though the impact is scale and context specific, highlighting the need for safeguards to ensure that expansion of land for mitigation does not impact natural systems and food security. A number of practices, such as increased food productivity, dietary change and reduced food loss and waste, can reduce demand for land conversion, thereby potentially freeing‐up land and creating opportunities for enhanced implementation of other practices, making them important components of portfolios of practices to address the combined land challenges.  相似文献   
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The chemical, brewing and anti-microbial properties of a tropical seed,Garcinia kola, were compared with traditional hops. Treatment ofGarcinia kola with methanolic lead acetate produced a yellow precipitate from which organic acids (alpha acids) were contirmed to be present by thin-layer chromatography. Hops, however, had a higher concentration of organic acids thanGarcinia kola. Laboratory brewing trials withGarcinia kola and hops gave beers with simillar chemical properties. Organoleptically,Garcinia kola beer was as acceptable to tasters as hopped beer except that it had an improved bitterness.Garcinia kola and hop extracts exerted similar anti-microbial effects on two beer spollage micro-organisms (Lactobacillus delbruckii andCandida vini).
Résumé On a comparé les propriétés chimiques, brassicoles, et antiseptiques d'une graine tropicale,Garcinia kola, à celles des houblons traditionnels. Le traitement deGarcinia kola à l'acétate de plomb en milieu méthanolique a produit un précipité jaune dans lequel on a confirmé la présence d'acides organiques ou acides . Les houblons, toutefois, avaient une concentration plus élevée en acides organiques queGarcinia kola. Des essais de brassage au laboratoire avecGarcinia kola ont produit des bières aux propriétés chimiques sembiables. Sur le plan organolètique, la bière deGarcinia kola a été aussi acceptable pour les goûteurs que la bière de houblon à ceci prés que la première avait une amertume améliorée. Les extraits deGarcinia kola et de houblon ont exercé des effets antimicrobiens semblables sur deux microorganismes contaminant la bière (Lactobacillus delbruckii etCandida vini).
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10.
Snow accumulation can influence soil properties in arctic and alpine tundra, boreal and temperate forests, and temperate grasslands. However, snow may be even more influential in arid ecosystems, which by definition are water limited, such as the hyper-arid polar desert of the McMurdo Dry Valleys, Antarctica. Moreover, snow accumulation may be altered by climate change in the future. In order to investigate the impact of changes in snow accumulation on soils in the McMurdo Dry Valleys we experimentally manipulated the quantity of snow at two locations and monitored soil properties over 5 years in relation to a snow depth gradient created by snow fences. We predicted that increased snow depth would be associated with increased soil moisture and a shift in soil animal community structure. While we did not observe changes in soil biochemistry or community structure along the snow depth gradient at either site, increased snow accumulation caused by the snow fence altered soil properties across the entire length of the transects at one site (Fryxell), which collected substantially more snow than the other site. At Fryxell, the presence of the snow fence increased gravimetric soil moisture from 1 to 5–9%. This was associated with a decline in abundance of the dominant animal, Scottnema lindsayae, a nematode typically found in dry soil, and an increase in Eudorylaimus sp. a nematode associated with moist soil. We also observed changes in soil pH, salinity, and concentrations of inorganic nitrogen and chlorophyll a over the course of the experiment, but it was difficult to determine if these were caused by snow accumulation or simply represented temporal variation related to other factors.  相似文献   
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