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Yea Hwang MOON Ji Un OK Shin Ja LEE Jong Kyu HA Sung Sill LEE 《Animal Science Journal》2010,81(6):642-647
A comparative study among Korean native cow (Hanwoo), Holstein dairy cow, Korean native goat and crossbred sheep on the population and marker concentration of ruminal microbes, the activities of carboxymethylcellulase (CMCase), xylanase and amylase, and in situ dry matter (DM) degradability were conducted. Twelve ruminally cannulated animals, three of each species, were used. Animals were fed the same diet containing 40% formula feed and 60% rice straw at the level of 2.5% of body weight. Total viable microbial populations in the rumen fluid were significantly (P < 0.01) greater for bacteria and fungi in goat than those of Holstein. The protozoan population among ruminant species was the reverse from that of bacteria. The concentrations of 2,6‐diaminopimelic acid and chitin as markers for bacteria and fungi in the rumen fluid, respectively, were highest in goat, which is in accordance with the above population data. The concentration of aminoethylphosphonic acid as marker of protozoa was highest in Hanwoo and lowest in sheep (P < 0.01). Goat had the highest (P < 0.01) activities of all the enzymes investigated among ruminants. In situ effective degradation of the DM of rice straw was approximately 19% higher in the rumen of goat compared with other animals. 相似文献
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A. R. A. USMAN M. I. AL-WABEL Y. S. OK A. AL-HARBI M. WAHB-ALLAH A. H. EL-NAGGAR M. AHMAD A. Al-FARAJ A. AL-OMRAN 《土壤圈》2016,26(1):27-38
Thermally modified organic materials commonly known as biochar have gained popularity of being used as a soil amendment.Little information, however, is available on the role of biochar in alleviating the negative impacts of saline water on soil productivity and plant growth. This study, therefore, was conducted to investigate the effects of Conocarpus biochar(BC) and organic farm residues(FR) at different application rates of 0.0%(control), 4.0% and 8.0%(weight/weight) on yield and quality of tomatoes grown on a sandy soil under drip irrigation with saline or non-saline water. The availability of P, K, Fe, Mn, Zn and Cu to plants was also investigated. The results demonstrated clearly that addition of BC or FR increased the vegetative growth, yield and quality parameters in all irrigation treatments. It was found that salt stress adversely affected soil productivity, as indicated by the lower vegetative growth and yield components of tomato plants. However, this suppressing effect on the vegetative growth and yield tended to decline with application of FR or BC, especially at the high application rate and in the presence of biochar. Under saline irrigation system, for instance, the total tomato yield increased over the control by 14.0%–43.3% with BC and by 3.9%–35.6% with FR. These could be attributed to enhancement effects of FR or BC on soil properties, as indicated by increases in soil organic matter content and nutrient availability. Therefore, biochar may be effectively used as a soil amendment for enhancing the productivity of salt-affected sandy soils under arid conditions. 相似文献
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Alberta油砂地区在两种水文流域森林土壤酸化敏感性研究 总被引：2，自引：0，他引：2
Input of large amounts of N and S compounds into forest ecosystems through atmospheric deposition is a significant risk for soil acidification in the oil sands region of Alberta. We evaluated the sensitivity of forest soils to acidification in two watersheds （Lake 287 and Lake 185） with contrasting hydrological regimes as a part of a larger project assessing the role of N and S cycling in soil acidification in forest ecosystems. Fifty six forest soil samples were collected from the two watersheds by horizon from 10 monitoring plots dominated by either jack pine （Pinus banksiana） or aspen （Populus tremuloides）. Soils in the two watersheds were extremely to moderately acidic with pH （CaCl2） ranging from 2.83 to 4.91. Soil acid-base chemistry variables such as pH, base saturation, Al saturation, and acid-buffering capacity measured using the acetic acid equilibrium procedure indicated that soils in Lake 287 were more acidified than those in Lake 185. Acid-buffering capacity decreased in the order of forest floor 〉 subsurface mineral soil 〉 surface mineral soil. The most dramatic differences in percent Ca and Al saturations between the two watersheds were found in the surface mineral soil horizon. Percent Ca and Al saturation in the surface mineral soil in Lake 287 were 15% and 70%, respectively; the percent Ca saturation value fell within a critical range proposed in the literature that indicates soil acidification. Our results suggest that the soils in the two watersheds have low acid buffering capacity and would be sensitive to increased acidic deposition in the region. 相似文献
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近年来,生物炭在污染土壤修复中的研究与应用受到广泛关注,且已被证实对于修复土壤重金属及有机污染具有显著的效果。生物炭可以改善土壤性质,影响土壤微生物群落,实现生物炭介导的微生物土壤污染修复。本文综述了生物炭对微生物的积极作用,包括提供额外生存环境、提供营养物质和改善原有栖息地[土壤团聚性、pH、阳离子交换能力（CEC）和酶活性]。这些影响将导致微生物丰度、活性和群落结构的变化。然而,生物炭所携带的可能威胁微生物群落的有毒物质也不应被忽视,如多环芳烃、呋喃等;同时生物炭在高温热解过程中产生的持久性自由基也会对微生物产生毒性。本文还讨论了生物炭介导的微生物修复技术在去除土壤污染物方面的应用现状,最后对生物炭-微生物交互作用在土壤污染修复中的研究方向提出了展望。 相似文献
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