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XIONG Zheng-qin Xing Guang-xi H Tsuruta Shi Shu-Lian SHEN Guang-yu DU Li-juan QIAN Wei 《中国农业科学(英文版)》2002,1(9):977-981
A field study was conducted to investigate the effects of leguminous crop cultivation on nitrousoxide (N2O) emissions from upland agricultural soils. Results demonstrated that N2O emission sequences were tively. While in terms of seasonal emission, the sequence was that soybean ＞ peanut crop ＞ upland rice, being 0.77, 0.70 and 0.55 kg/ha respectively. Results also demonstrated that legume crop treatment emitted much more N2O than non-legume upland rice treatment and that N fertilized treatments emitted more than unand N fertilizer, therefore, were one of the important sources of N2O emissions from agricultural fields. 相似文献
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冬季耕作制度对农田氧化亚氮排放的贡献 总被引：7，自引：0，他引：7
研究了红壤丘陵地区大田条件下旱地种植冬季豆科作物、油料作物、休闲 ,以及水稻田冬季休闲、种植紫云英绿肥后 ,土壤氧化亚氮 (N2 O)的排放。结果表明 ,水稻田冬季种植紫云英 ,N2 O平均排放通量 (以N计 ,以下同 )为11 1μg·m-2 ·h-1,比休闲田 (18 3μg·m-2 ·h-1)降低 39% ;旱地种植豌豆 ,N2 O平均排放通量只有 6 9μg·m-2 ·h-1,显著低于休闲田 (9 6 μg·m-2 ·h-1) ,也显著低于油菜田 (12 2 μg·m-2 ·h-1)。各作物施肥后土壤N2 O的排放量均增加 ,豌豆田N2 O平均排放通量为 10 0 μg·m-2 ·h-1,仍显著低于油菜田 (14 7μg·m-2 ·h-1)。因此 ,冬季种植豆科作物可显著降低稻田以及旱地农田N2 O的排放量 相似文献
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Timing of acorn development and abortion is an important maternal strategy in oak sexual reproduction. To understand the significance
of acorn abortion in Quercus serrata, artificial pollination of different mating patterns (outcross, self-, and nonpollination) was performed, and the timing
of abortion and the size and internal development of acorns from each mating type were investigated. Acorns were aborted similarly
in every pollination treatment until 80 days after pollination. Almost all self- and nonpollinated acorns were rapidly aborted
during the period 80–120 days after pollination. During that period, differences in internal fruit development between outcross-pollinated
and unsuitably pollinated (self- and nonpolinated) acorns were observed. In addition, cotyledon development and a rapid increase
in fruit size were observed in the acorns gained by outcross pollination. The correspondence between the timing of abortion
and the timing of rapid size growth and the development of storage organs suggests that this acorn-maintenance strategy may
be the consequence of a maternal adaptation that allows better reproductive success under resource limitation. 相似文献
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Aguilar I Misztal I Legarra A Tsuruta S 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2011,128(6):422-428
Genomic evaluations can be calculated using a unified procedure that combines phenotypic, pedigree and genomic information. Implementation of such a procedure requires the inverse of the relationship matrix based on pedigree and genomic relationships. The objective of this study was to investigate efficient computing options to create relationship matrices based on genomic markers and pedigree information as well as their inverses. SNP maker information was simulated for a panel of 40 K SNPs, with the number of genotyped animals up to 30 000. Matrix multiplication in the computation of the genomic relationship was by a simple 'do' loop, by two optimized versions of the loop, and by a specific matrix multiplication subroutine. Inversion was by a generalized inverse algorithm and by a LAPACK subroutine. With the most efficient choices and parallel processing, creation of matrices for 30 000 animals would take a few hours. Matrices required to implement a unified approach can be computed efficiently. Optimizations can be either by modifications of existing code or by the use of efficient automatic optimizations provided by open source or third-party libraries. 相似文献
56.
Zumbach B Misztal I Tsuruta S Sanchez JP Azain M Herring W Holl J Long T Culbertson M 《Journal of animal science》2008,86(9):2076-2081
The objective of this study was to describe genetic variability of pig carcass weight as a function of heat stress. Data included carcass weights of 23,556 crossbred pigs [Duroc x (Landrace x Large White)] raised on 2 farms in North Carolina and harvested from May 2005 through December 2006. Weather data were obtained from a weather station located about 20 km from the furthest farm. Weekly heat load was calculated as degrees of average temperature-humidity index (THI) in excess of 18 degrees C. The total heat load (H) was the sum of heat loads for 10 wk before harvest. Variance components were estimated with 3 models: univariate (UNI)-not accounting for heat stress, 2-trait (MT2), and random regression (RR). In all of the models, effects included contemporary group, sex, age at harvest, sire, and litter. In MT2, observations in months in which heat stress was observed ("hot") and not observed ("cold") were treated as separate traits. Heat stress was observed in the months of August to November 2005, as well as July to October 2006. No heat stress was observed in the months of May to July 2005, January to June 2006, and November to December 2006. The RR model added a random regression on heat load for the sire effect. Heat load was adjusted to a scale ranging from 0 (no heat stress) to 5 (greatest heat stress). The heritability estimate +/- SE of carcass weight in UNI was 0.17 +/- 0.01. In MT2, the estimates were 0.14 +/- 0.01 for "cold" and 0.28 +/- 0.01 for "hot"; the genetic correlation between carcass weight in "hot" and "cold" months was 0.42 +/- 0.13. The heritability estimates obtained with RR were 0.20 +/- 0.11, 0.19 +/- 0.15, and 0.51 +/- 0.17 for H = 0, 2.5, and 5, respectively. The genetic correlation between the performance in "cold" months (H = 0), and performance under maximum heat load (H = 5) was 0.02, between H = 0 and intermediate heat load (H = 2.5) was 0.52, and between H = 2.5 and H = 5 was 0.86. Rank correlations between EPD derived from the different models ranged from 0.82 to 0.94 between carcass weights under similar H, 0.18 to 0.54 between carcass weights under high and low H, and 0.66 to 0.91 between carcass weights of intermediate and high/low H. Heritability for growth was greater under heat stress. Selection for crossbred performance would be optimal when data for periods both in the absence and presence of heat stress were considered. 相似文献
57.
Haoming Wu Qui D. Nguyen Tu T. M. Tran Minh T. Tang Takeshi Tsuruta Naoki Nishino 《Animal Science Journal》2019,90(3):445-452
Microbiota of the gut, milk, and cowshed environment were examined at two dairy farms managed by automatic milking systems (AMS). Feed, rumen fluid, feces, milk, bedding, water, and airborne dust were collected and the microbiota on each was assessed by Illumina MiSeq sequencing. The most abundant taxa in feed, rumen fluid, feces, bedding, and water were Lactobacillaceae, Prevotellaceae, Ruminococcaceae, Ruminococcaceae, and Lactobacillaceae, respectively, at both farms. Aerococcaceae was the most abundant taxon in milk and airborne dust microbiota at farm 1, and Staphylococcaceae and Lactobacillaceae were the most abundant taxa in milk and airborne dust microbiota at farm 2. The three most prevalent taxa (Aerococcaceae, Staphylococcaceae, and Ruminococcaceae at farm 1 and Staphylococcaceae, Lactobacillaceae, and Ruminococcaceae at farm 2) were shared between milk and airborne dust microbiota. Indeed, SourceTracker indicated that milk microbiota was related with airborne dust microbiota. Meanwhile, hierarchical clustering and canonical analysis of principal coordinates demonstrated that the milk microbiota was associated with the bedding microbiota but clearly separated from feed, rumen fluid, feces, and water microbiota. Although our findings were derived from only two case studies, the importance of cowshed management for milk quality control and mastitis prevention was emphasized at farms managed by AMS. 相似文献
58.
Madeline Thurlow Ken-ichi Kanda Haruo Tsuruta Katsuyuki Minami 《Soil Science and Plant Nutrition》2013,59(2):371-375
Abstract Methane (CH4) is one of the most abundant organic gases in the atmosphere. Recently the importance of CH4 as a greenhouse gas has been recognized and studies have been carried out to assess its contribution to global warming. Although the rate of increase has slowed down in the last decade (Steel et al. 1992; Rudolph 1994), the results from some of these studies have shown that the atmospheric concentration of CH4 is increasing at a rate estimated to be approximately 1% per year (Rowland 1991; Blake and Rowland 1988; Bolle et al. 1986; Graedel and McRae 1980). Clearly it is important to identify sources and sinks of CH4, in both terrestrial and oceanic ecosystems, in order to estimate global methane budgets (Cicerone and Oremland 1988). 相似文献
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To understand the underlying factors affecting the seasonal variation of the methane concentration in a cool temperate freshwater marsh vegetated with Carex lasiocarpa in the Sanjiang Plain of northeast China, we measured methane emission from, and the concentrations of methane, dissolved organic carbon (DOC) and acetate in, water samples taken from the standing water surface to the top of the gley soil layer in the C. laisocarpa marsh, before and after plants were covered with a black cloth at the three growing stages of June, July and August 2002. The methane oxidation rate was also measured in situ by applying acetylene, a methane oxidation inhibitor, to whole plants, and the methane production rate in water sampled in June and July was measured via the anaerobic incubation in the laboratory. The methane production rate in water samples was significantly correlated with acetate concentration rather than DOC concentration, whereas the mean acetate concentration in water samples was higher in June than in July and August. Hence, the low methane concentration in June did not result from a lack of acetate for methane production. The mean methane and DOC concentrations in water samples were enhanced by 22.3 and 31.1% in June, 2.1 and 5.0% in July, and 3.4 and 15.2% in August, respectively, after plants were covered with a black cloth. The methane oxidation rate and redox potential in the freshwater marsh decreased from June to July or August. These results suggest that there was more oxygen in the rhizome and rhizosphere in June than in July and August, which not only accentuated methane oxidation but also reduced methane production. Therefore, the high methane concentration in water in July and August could be ascribed to both an increase in temperature and a decrease in redox potential or oxygen concentration in the rhizosphere. 相似文献