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基于灰色理论的延边地区畜禽养殖环境承载力研究 总被引:1,自引:0,他引:1
《中国畜牧杂志》2016,(20)
本文结合2008—2014年延边地区畜禽养殖发展现状,构建了延边地区畜禽养殖环境承载力评价指标体系,并采用系统分析模型对分析年份延边地区畜禽养殖环境承载力综合值进行了量化;同时运用灰色数列预测模型对延边地区2015—2025年畜禽养殖环境承载力进行了预测。结果表明,延边地区畜禽养殖环境承载力适宜值与警戒值分别为0.241和0.234;2008—2014年畜禽养殖环境承载力综合值均大于适宜值,且逐渐偏离适宜值,延边地区畜禽养殖环境承载能力较强。而2015—2025年间畜禽养殖环境承载力综合值也均大于适宜值,发展前景乐观,可进行持续性发展。 相似文献
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四川省达州市属于南方丘陵多雨区,以山地为主,地势起伏大,立体气候特征明显,种植制度多样,人均耕地较少,坡耕地比重大,农作物秸秆种类繁多,收储运难度大.生猪养殖比重大,禽养殖散养与规模养殖并存,畜禽粪便随意排放,对小流域环境有严重影响,生态承载压力大.区域内生态脆弱,水土配置错位,资源性和工程性缺水严重,资源环境承载力有... 相似文献
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随着国家对农业面源污染治理的重视,如何对畜禽养殖粪污无害化处理利用已成为畜牧养殖行业发展亟需解决的难题.目前我国对畜禽养殖粪污污染治理还存在薄弱环节,要实现畜牧养殖业的可持续发展,必须对畜禽粪便进行综合治理.畜禽污染与其他工业污染不同,它具有双面性,一是对环境造成污染,这是消极的一面;积极的一面是通过处理可作为再生资源... 相似文献
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为了科学评估潍坊市2012—2021年畜禽粪污土地承载力时空分布状况,准确评价畜禽养殖潜在环境风险状况,研究采用产排污系数法对潍坊市各县(市、区)2012—2021年畜禽粪污产生量、养分供给量、植物粪肥养分需求量及土地承载力指数等畜禽粪污土地承载力时空分布特征指标进行了分析。结果表明:潍坊市畜禽粪污土地承载力状况存在明显的时空分异特征。从时间上看,2012—2021年潍坊市各县(市、区)畜禽粪污产生量、养分供给量及植物粪肥养分需求量具有高度相似性,均呈现缓慢减少→稳定发展趋势。以氮、磷为基准的土地承载力指数(IN、IP)均呈现相对稳定趋势,其中IN均小于0.7,属于Ⅰ级,土地承载力有较大发展空间。除2017年外,其他年份IP均在0.7~1.0之间,属于Ⅱ级,土地承载力尚有发展空间。从空间上看,潍坊市各县(市、区)畜禽粪污产生量、养分供给量及植物粪肥养分需求量具有高度相似性,均呈现四周多中间少、东南和西北较多的分布特征。IN、IP存在一定差异,除临朐县外,其... 相似文献
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魏静 《四川畜牧兽医学院学报》2009,(4):28-32
在现代法律秩序中,商会自治规范是制定法的基础和必要的补充,甚至在某些方面替代了制定法;商会自治规范主要包括商会组织规范、行为规范、惩罚规范以及争端解决规范等;其效力仅及于其内部成员;商会自治规范和制定法之间存在冲突,但也存在整合的基础。 相似文献
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本文概述了猪的毛色类型、猪的毛色遗传模式,着重综述了猪毛色基因分子基础的研究进展,指出存在问题并就未来发展方向做了思考。 相似文献
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REASONS FOR PERFORMING STUDY: Centesis of the bicipital bursa using an 8.9 cm long spinal needle has been reported but the alternative of employing a 3.8 cm long hypodermic needle requires validation. OBJECTIVE: To compare the efficacy of 2 different methods of centesis of the bicipital bursa and to evaluate the usefulness of ultrasonographic imaging to determine the location of solution administered when centesis of the bursa is attempted. METHODS: For Trial 1, 6 clinicians, who had no previous experience of centesis of the bicipital bursa, attempted to inject a solution composed of an aqueous radiopaque contrast medium and physiological saline solution (PSS) into the bicipital bursae of 2/12 horses using the previously described distal approach to inject one bursa and a proximal approach to inject the contralateral bursa. The bicipital tendon and bursa were examined ultrasonographically before and after injection; and both shoulders were examined radiographically to identify the location of the medium. In Trial 2, another 6 clinicians, also with no previous experience of centesis, repeated Trial 1, using 6 horses, but the radiopaque contrast medium was mixed with air instead of PSS. RESULTS: Accuracy of centesis using the proximal approach was 39% and that of the distal approach 28%. Ultrasonographic examination of the shoulder allowed the location of solution and air to be accurately predicted in all 12 shoulders examined. CONCLUSIONS: Clinicians who have had no previous experience performing centesis of the bicipital bursa are unlikely to be successful in centesis using either approach. Radiographic examination after injecting a radiopaque contrast medium may be necessary to assess the success of centesis especially if bursal fluid is not obtained during centesis. Injecting air along with the radiopaque contrast medium provides more accurate ultrasonographic confirmation of centesis and better radiographic definition than does injection without air. 相似文献
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以国际标准强毒R株人工感染非免疫产蛋鸡,定时扑杀,分别从鼻窦、眶下孔、气管、肺、气囊、卵巢和输卵管分离MG,并收集感染鸡所产蛋分离MG。结果表明,人工感染48小时后上、下呼吸道及肺已被全面感染,96小时气囊已被感染,120小时输卵管已能分离到MG,卵巢始终分离不到MG。人工感染鸡自144小时便能在其所产蛋中分离出MG。药物治疗能在72小时内消除感染,油乳剂苗则需24天后逐渐降低蛋内MG分离率,药物卵内注射、种蛋药浴、高温处理均能杀死卵内MG,但以研制的种蛋浸泡剂药浴效果为最好。 相似文献
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Effects of size of ingestively masticated fragments of plant tissues on kinetics of digestion of NDF
Ingestively masticated fragments were collected and sized via sieving. Different sizes of esophageal masticate and ruminal digesta fragments, and ground fragments of larger masticated pieces were incubated in vitro, and undigested NDF remaining at intervals of up to 168 h of incubation was determined. The ruminal age-dependent time delay (tau) for onset of digestion of NDF was positively correlated (P < 0.004) with the mean sieve aperture estimated to retain 50% of the fragments between successive sieve apertures (MRA). Degradation rate of potentially degradable NDF (PDF) and level of indigestible NDF were not related (P > 0.10) to MRA of masticated and ground fragments. Estimates of tau were positively related to MRA, with slopes of bermudagrass < corn silage < ruminal fragments of corn silage. It was concluded that fragment size-, and consequently, ruminal age-dependent onset of PDF degradation of a mixture of different fragment sizes results in an age-dependent rate of degradation of the more rapidly degrading of two subentities of PDF. Models are proposed that assume a tau before onset of simultaneous degradation of PDF from two pools characterized as having gamma-modeled age-dependency and age-constant rates. The ruminal age-dependent pool seems to be associated with the faster-degrading pool, and its rate parameter increases with range in MRA in the population of fragments. Conceptually, the ruminal age-dependent rate parameter for PDF degradation seems to represent a composite of several effects: 1) effects of the size-dependent tau; 2) range in MRA of the population of ingestively masticated fragments; and 3) subentities of PDF that degrade via more rapid age-dependent rates compared with subentities of PDF that degrade via age-constant rates. The estimated fractional rates of ruminative comminution of ingestively masticated fragments (0.060 to 0.075/h) were of a magnitude similar to the mean fractional rates of PDF digestion (0.030 to 0.085/h), which implies that ruminative comminution may be first-limiting to fractional rate of PDF digestion. The in vivo roles of ingestive and ruminative mastication of fragments on PDF degradation must be considered in any kinetic system for estimating PDF digestion in the rumen. These results and others in the literature suggest that the rate of surface area exposure rather than intrinsic chemical attributes of PDF may be first-limiting to degradation rate of PDF in vivo. 相似文献