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221.
Xiaomin Feng Hongjun Gao Rattan Lal Ping Zhu Chang Peng Aixing Deng 《Archives of Agronomy and Soil Science》2013,59(13):1831-1844
ABSTRACTA long-term field experiment was performed to assess the effects of fertilization regimes on greenhouse gas emissions, soil properties, soil denitrifies, and maize (Zea mays) grain yield on Mollisols of Northeastern China. Chemical nitrogen (N), phosphorus (P), and potassium (K) fertilizers plus pig manure (MNPK) treatment significantly increased soil N2O emissions by 29.9–226.4% and global warming potential (GWP) by 29.8–230.7% compared to unfertilized control (CK), chemical N fertilizer only (N), chemical N, P, and K fertilizers (NPK) and chemical N, P, and K fertilizers plus corn straw (SNPK) treatments. However, the MNPK treatment yielded similar greenhouse gas intensity (GHGI) as compared with other treatments, mainly due to higher maize grain yield. There were also higher gene copy numbers of nirK, nirS, and nosZ in topsoil (0–20 cm depth) under MNPK treatment. Automatic linear modeling analysis indicated that main factors influencing soil N2O emissions were soil organic carbon (SOC), NO3? content, and nirK gene abundance. Although the application of chemical fertilizers plus organic manure increases N2O emissions due to higher N and C availability and nirK gene activity in the soil, this is still a promising fertilizer management due to its notable enhancement of maize grain yield and SOC content. 相似文献
222.
G. Lal M.S. Fageria R.S. Dhaka S. K. Khandelwal 《The Journal of Horticultural Science and Biotechnology》2013,88(5):576-579
SummaryAn experiment was conducted to study the effect of postharvest water dipping treatments and storage conditions on shelf life and quality of ber (Ziziphus mauritianaLamk). Fresh fruits of ber ‘Umran ’ were dipped in either cold (128C) or hot (50?C) water for 5 min and packed under different storage containers i.e. corrugated fibre board boxes, sealed polythene bags and perforated polythene bags. Control fruits were packed without dipping treatment. Result showed that postharvest water dipping at 508C for 5 min significantly increased the shelf life and maintained the quality of ber fruits, particularly late in the storage period. Fruits packed in sealed polythene bags significantly lowered the loss in fruit weight, spoilage and ripening with consequent increase in acidity and organoleptic score. Interactive results showed that hot-water treated fruits stored in modified atmospheric bags (sealed polythene bags) were qualitatively better than control fruits in terms of colour, taste and appearance. The organoleptic score reveals the acceptability of these fruits even after day 8 of storage. The control fruits were not found acceptable after day 4 of storage. It is suggested that postharvest fruit dipping in hot water (508C) forfive minutes followed by packaging in sealed polythene bags can enhance the shelf life and quality of ber fruits. 相似文献
223.
The energetic nuclei in cosmic rays interact with meteoroids, the moon, planets, and other solar system matter. The nuclides and heavy nuclei tracks produced by the cosmic-ray particles in these targets contain a wealth of information about the history of the objects and temporal and spatial variations in the particle fluxes. Most lunar samples and meny meteorites have complex histories of cosmicray exposure from erosion, gardening, fragmentation, orbital changes, and other processes. There appear to be variations in the past fluxes of solar particles, and possibly also galactic cosmic rays, on time scales of 10(4) to 10(7) years. 相似文献
224.
Samples of eight geographically distinct soils contaminated with crude oil were screened for polyhydroxyalkanoic acid (PHA) producing bacterial strains. Twenty three bacterial strains were able to accumulate PHA when sodium gluconate or sodium octanoate was used as the sole carbon source. Biochemical tests and 16S rRNA sequencing identified bacteria of the genera Pseudomonas, Acinetobacter, Sphingobacterium, Brochothrix, Caulobacter, Ralstonia, Burkholderia and Yokenella. Three of the bacterial strains have never been reported to produce PHA. The phylogenetic analysis of the PHA synthase (phaC) gene of these bacteria showed a close homology with the phaC gene of different Pseudomonas species.This study indicates that stressed environments like oil-contaminated sites can be potential sources of medium-chain-length PHA producers. 相似文献
225.
The radioactivity of aluminum-26 in two cores of Pacific sediments is an order of magnitude higher than was expected, as a result of its production by cosmic-ray interactions in the terrestrial environment. The higher activity can be explained only by postulating influx with extraterrestrial cosmic dust that had been exposed to significant flux of energetic particles capable of producing nuclear interactions. These particles may well be the "solar" cosmic rays that are sporadically accelerated by Sun during certain solar flares, since the steady galactic cosmic-ray flux is inadequate. The long-term average flux of low-energy protons in interplanetary space, required to yield the observed rate of influx of aluminum-26, is deduced on the basis of certain assumptions. 相似文献
226.
Lelieveld J Crutzen PJ Ramanathan V Andreae MO Brenninkmeijer CM Campos T Cass GR Dickerson RR Fischer H de Gouw JA Hansel A Jefferson A Kley D de Laat AT Lal S Lawrence MG Lobert JM Mayol-Bracero OL Mitra AP Novakov T Oltmans SJ Prather KA Reiner T Rodhe H Scheeren HA Sikka D Williams J 《Science (New York, N.Y.)》2001,291(5506):1031-1036
The Indian Ocean Experiment (INDOEX) was an international, multiplatform field campaign to measure long-range transport of air pollution from South and Southeast Asia toward the Indian Ocean during the dry monsoon season in January to March 1999. Surprisingly high pollution levels were observed over the entire northern Indian Ocean toward the Intertropical Convergence Zone at about 6 degrees S. We show that agricultural burning and especially biofuel use enhance carbon monoxide concentrations. Fossil fuel combustion and biomass burning cause a high aerosol loading. The growing pollution in this region gives rise to extensive air quality degradation with local, regional, and global implications, including a reduction of the oxidizing power of the atmosphere. 相似文献
227.
A good knowledge of the specificities of the animal trade network is highly valuable to better control pathogen spread on a large regional to transnational scale. Because of their temporal dynamical nature, studying multi-annual datasets is particularly needed to investigate whether structural patterns are stable over the years. In this study, we analysed the French cattle movement network from 2005 to 2009 for different spatial granularities and temporal windows, with the three-fold objective of exploring temporal variations of the main network characteristics, computing proxies for pathogen spread on this network, which accounts for its time-varying properties and identifying specificities related to the main types of animals and farms (dairy versus beef). Network properties did not qualitatively vary among different temporal and spatial granularities. About 40% of the holdings and 80% of the communes were directly interconnected. The width of the aggregation time window barely impacted normalised distributions of indicators. A period of 8–16 weeks would suffice for robust estimation of their main trends, whereas longer periods would provide more details on tails. The dynamic nature of the network could be seen through the small overlap between consecutive networks with 65% of common active nodes for only 3% of common links over 2005–2009. To control pathogen spread on such a network, by reducing the largest strongly connected component by more than 80%, movements should be prevented from 1 to 5% of the holdings with the highest centrality in the previous year network. The analysis of breed-wise and herd-wise subnetworks, dairy, beef and mixed, reveals similar trends in temporal variation of average indicators and their distributions. The link-based backbones of beef subnetworks seem to be more stable over time than those of other subnetworks. At a regional scale, node reachability accounting for time-respecting paths, as proxy of epidemic burden, is greater for a dairy region than for a beef region. This highlights the importance of considering local specificities and temporal dynamics of animal trade networks when evaluating control measures of pathogen spread. 相似文献
228.
Recent years have witnessed a rise in sensitivity towards protection of natural genetic resources and the environment at the
international level. This is evident from the implementation of the convention on biodiversity (CBD). To conserve and optimize
utilization of its bioresources, India enacted the Biological Diversity Act 2002. The conservation and management of aquatic
resources is important for sustainable utilization of fisheries potential for the economic advancement of farmers and fishery
workers, today as well as for posterity. As the biotechnological and genomic revolutions are ready to take off, the sovereign
rights of native inhabitants to intellectual property rights (IPR) related to aquatic genetic resources and associated traditional
knowledge are also integral components of management strategies for genetic resources. 相似文献
229.
This study describes the development and validation of competitive antigen capture enzyme-linked immunosorbent assay (ELISA)
for growth hormone (GH) of the catfish, Clarias batrachus. Isolated GH was characterized first through bioassay, amino acid sequencing, immunoblotting and immunocytochemistry, and
then used to raise antibody to develop ELISA. The lowest detection limit of the assay system was 0.17 ng ml−1, and the standard curve had an ED50 value of 0.35 ng ml−1. Repeated determination of GH in a plasma pool exhibited intra- and interassay co-efficient of variation of 8.1% and 7.09%
(n=5), respectively. Dose–response inhibition curves resulting from dilutions of plasma and pituitary homogenate of C. batrachus were parallel to the standard curve, while such parallelism in the case of Cyprinus carpio and H. fossilis was absent revealing no cross reaction of them in the present ELISA. In vivo effects of sGnRH, testosterone, 5-HT and morphine
on plasma GH were also examined to validate the ELISA physiologically. sGnRH, testosterone and morphine increased, while 5-HT
decreased GH level in a dose-dependent manner. 相似文献
230.
Nirmala Saini Baldev Dass Kiradoo Dau Lal Bohra 《Tropical animal health and production》2014,46(6):987-994
The experiment was undertaken on 20 pre-pubescent dromedary camels of 300?±?7.0 kg average bodyweight (BW) and 1.5–2 years of age to determine change in body weight, blood biochemical and mineral profiles and morphometric parameters on rangeland grazing (GR) and supplementary stall feeding (GS) at arid northwestern part of Rajasthan over a period of 80 days. GR camels were maintained only on grazing, while GS camels were fed semi-intensively ad-lib groundnut haulms along with formulated concentrate and mineral mixture to meet maintenance requirement. Intake of young camels was determined using chromium(III) oxide as internal marker. The biomass yield of rangeland estimated was 0.54 t DM/ha. Dry matter intake (kg/day) by GR camels on rangeland grazing was lower than that by GS camels fed on supplementary feeding. The nutrient digestibility of dry matter and organic matter (P?<?0.05) and crude protein was higher in GS camels than that in GR camels. Likewise, intake of digestible crude protein (P?<?0.05) and metabolizable energy were higher in stall-fed young camels. Pre-pubescent camels fed on grazing had significantly (P?<?0.01) low glucose and higher urea concentration compared to stall-fed camels. Final body weight of camels differed significantly (P?<?0.05) between groups. The camels fed on supplementary stall feeding had significantly (P?<?0.01) higher total gain (kg) and average daily gain (ADG) compared to camels on grazing. Among morphometric parameters, body length and body height showed more significant increase in GS compared to GR camels. Intake of digestible crude protein (DCP) by GR group was 43 % low compared to the requirement for growing camel of 300 kg body weight. Despite this, GR camels were able to maintain body weight due to better recycling of urea which was significantly higher in comparison to GS camels. The findings of significantly (P?<?0.01) low serum glucose and higher urea concentration and lower body weight gain of GR camels suggest the need of locally available protein and energy supplement in addition to grazing for better growth performance. 相似文献