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596.
Water transfer from agriculture to urban uses: lessons learned, with policy considerations 总被引:1,自引:0,他引:1
This paper sets forth the accomplishments to date of the international collaborative study program on efficient and equitable
transfer of water from agriculture to other uses. The research consists of several components. First a bibliographical review
was prepared of literature available on the practice of inter-sector water transfer. Second, nine case studies have been prepared
that illustrate inter-sector water transfer under a variety of physical and economic and political environments. Third, a
framework has been developed for characterizing and comparing water transfer options and compensation among case studies.
We discuss the pricing of irrigation water in determining compensation. We develop a decision tree that traces the paths to
the various sector water transfer options. Finally, we discuss water transfer policy options with specific reference to Taiwan,
though they have more general relevance. Three options are identified which reflect different objectives for government intervention. 相似文献
597.
Meinhard Breiling Shizuka Hashimoto Yohei Sato Gilbert Ahamer 《Paddy and Water Environment》2005,3(1):39-46
The contribution of rice production to the three major greenhouse gases CO2, CH4 and N2O in 1990, the base year of the Kyoto protocol is investigated for Japan. For the CO2 assessment, we use a top-down life cycle approach, CH4 is assessed using the Japanese GHG emission inventory and N2O is assessed according to the ratio of rice area divided by the total area of agricultural soils. In total, 1.6% of greenhouse gas (GHG) emissions in 1990 originated from rice production. Next, we assess regional variations in nine rice-producing regions, based on the CO2 data of 1990. General trends in rice production from 1960 to 2000 and data from the Japanese GHG emission inventory since 1990 are used to assess variations in time. The rice-related GHG emissions decreased to 1.05% of the total GHG emissions in 2001 and will be less than half the 1990 level in 2012, mainly due to the decrease in rice production. Contrary to the trend in GHG emissions of rice, overall GHG emissions increased as rice production fulfils important roles, in mitigating global warming and in adapting to changing climates. The protection of rice production is required to counter the increase of GHG emissions in transportation, waste and domestic sectors and to minimize problems related to landscape, water and natural hazard management. 相似文献
598.
Senyuva HZ Gilbert J Oztürkoglu S Ozcan S Gürel N 《Journal of agricultural and food chemistry》2008,56(20):9661-9666
An aqueous slurry of gamma-irradiated sterilized dried figs was inoculated with toxigenic strains of Aspergillus flavus and Aspergillus parasiticus. During incubation at 28 degrees C, pH, fructose, glucose, and free amino acids were determined by high-performance liquid chromatography and liquid chromatography (LC)/mass spectrometry, respectively, over 13 time points (1-20 days). At the same 13 time points using a LC/time-of-flight mass spectrometry screening method, aflatoxin B 1 and other secondary metabolites were simultaneously monitored. During the course of incubation, the pH significantly decreased and aflatoxin B 1 formation correlated with a reduction in proline content for both fungi. Of the 22 free amino acids that were monitored, only proline and cystine were found to be critical in supporting aflatoxin production. Levels of fructose and glucose steadily declined during incubation, until glucose was almost exhausted after 21 days. These time-course experiments confirmed the need for carbon and nitrogen sources for aflatoxin production in dried figs, and the favorable composition of figs as a fungal growth medium. 相似文献
599.
Reproductive performance of postpartum ewes treated with insulin or progesterone hormones in association with ram effect
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JC Ferreira‐Silva SRL Basto F Tenório Filho MT Moura ML Silva Filho MAL Oliveira 《Reproduction in domestic animals》2017,52(4):610-616
The reproductive performance of postpartum Santa Inês (SI) and Morada Nova (MN) ewes treated with insulin or progesterone hormones in association with ram effect was evaluated. Ewes from SI (n = 69) and MN (n = 69) breeds were randomly allocated to three groups of each breed (T1—ram effect only; T2—ram effect + insulin; T3—ram effect + progesterone). Progesterone concentrations (ηg/ml; mean ± SD) before and after introduction of rams (n = 6) were 0.51 ± 0.22 and 3.78 ± 0.68 (T1), 0.65 ± 0.21 and 3.77 ± 0.78 (T2) and 0.52 ± 0.21 and 3.84 ± 0.84 (T3) in SI ewes and 0.74 ± 0.19 and 3.71 ± 0.56 (T1), 0.70 ± 0.21 and 3.79 ± 0.75 (T2) and 0.81 ± 0.14 and 3.87 ± 0.80 (T3) in MN ewes, respectively. Thus, lower progesterone concentrations were found before the introduction of rams (p < .05). After the introduction of rams, preovulatory peaks of LH (ηg/ml) occurred at 28 (T1), 44 (T2) and 48 (T3) hr in SI ewes and at 64 (T1), 40 (T2) and 44 (T3) hr in MN ewes. The mean number of ovulations was similar between groups (p > .05), was 1.3 ± 0.51 (T1), 1.5 ± 0.54 (T2) and 1.6 ± 0.51 (T3) in SI ewes and 1.3 ± 0.51 (T1), 1.6 ± 0.51 (T2) and 1.6 ± 0.51 (T3) in MN ewes. In conclusion, the ram effect alone is effective at inducing and synchronizing oestrus in sheep under postpartum anoestrus, irrespective of hormone treatments. 相似文献
600.
V Dru A Bouquet O Zemb B Blanchet M L De Almeida L Cauquil C Carillier-Jacquin H Gilbert 《Journal of animal science》2022,100(6)
In pigs, the gut microbiota composition plays a major role in the process of digestion, but is influenced by many external factors, especially diet. To be used in breeding applications, genotype by diet interactions on microbiota composition have to be quantified, as well as their impact on genetic covariances with feed efficiency (FE) and digestive efficiency (DE) traits. This study aimed at determining the impact of an alternative diet on variance components of microbiota traits (genera and alpha diversity indices) and estimating genetic correlations between microbiota and efficiency traits for pigs fed a conventional (CO) or a high-fiber (HF) diet. Fecal microbes of 812 full-siblings fed a CO diet and 752 pigs fed the HF diet were characterized at 16 weeks of age by sequencing the V3-V4 region of the 16S rRNA gene. A total of 231 genera were identified. Digestibility coefficients of nitrogen, organic matter, and energy were predicted analyzing the same fecal samples with near infrared spectrometry. Daily feed intake, feed conversion ratio, residual feed intake and average daily gain (ADG) were also recorded. The 71 genera present in more than 20% of individuals were retained for genetic analyses. Heritability (h²) of microbiota traits were similar between diets (from null to 0.38 ± 0.12 in the CO diet and to 0.39 ± 0.12 in the HF diet). Only three out of the 24 genera and two alpha diversity indices with significant h² in both diets had genetic correlations across diets significantly different from 0.99 (P < 0.05), indicating limited genetic by diet interactions for these traits. When both diets were analyzed jointly, 59 genera had h² significantly different from zero. Based on the genetic correlations between these genera and ADG, FE, and DE traits, three groups of genera could be identified. A group of 29 genera had abundances favorably correlated with DE and FE traits, 14 genera were unfavorably correlated with DE traits, and the last group of 16 genera had abundances with correlations close to zero with production traits. However, genera abundances favorably correlated with DE and FE traits were unfavorably correlated with ADG, and vice versa. Alpha diversity indices had correlation patterns similar to the first group. In the end, genetic by diet interactions on gut microbiota composition of growing pigs were limited in this study. Based on this study, microbiota-based traits could be used as proxies to improve FE and DE in growing pigs. 相似文献