基于3S的草原沙化治理工程生态效益评价与实证研究

建立了草原沙化治理工程生态效益快速评价“植被－风沙活动－土壤”３个层次的指标体系,运用层次分析法确定了各个指标的权重,并对指标的域值进行了确定、量化和分级,选择镶黄旗翁贡乌拉苏木2种不同类型的治理工程做实例研究,建立相应的指标体系,地面调查和遥感解译相结合,运用研究提出的评价方法模型,对工程进行了生态效益评价。结果显示：2004年封沙育林工程得分为75.88分,生态效益良;2004年飞播造林工程得分为81.07分,生态效益优。     

沙化草原的治理方法

1生物治理栽植抗风沙、耐干旱能力强的优良草种和树种,建立良好的人工草地植被,是治理沙化草原,提高沙化草原生产力的关键措施。重度沙化草原治理方法是,     

沙化草原的治理方法

<正>1生物治理栽植抗风沙、耐干旱能力强的优良草种和树种,建立良好的人工草地植被,是治理沙化草原,提高沙化草原生产力的关键措施。重度沙化草原治理方法是,在围封禁牧的基础     

沙漠化草地的恢复与重建途径

在分析国内外草地沙漠化治理现状的基础上,研究1985-1998年沙化草地的自然恢复与人工恢复,结果表明:自然恢复属于进展演替类型,经历"沙生、一年生植物群落"、"根茎禾草杂类草群落"和"丛生禾草群落"三个演替阶段,最终向地带性植被类型发展;其植被物种组成,覆盖度、产草量均呈增加趋势,土壤有机质增加,表土结构变好;人工恢复的效果显著,播种抗旱、抗风沙型植物,可以快速建成植被覆盖地面,同时生产大量优质牧草,是我国沙化草原恢复重建的一条重要途径.     

关于喀左县保护草原沙化治理工程建设成果的思考

2009～2011年,辽宁省将全面实施辽西北草原沙化治理工程.每年治理沙化草原100万亩(1亩≈667m2),3年共治理300万亩.治理后,草原植被盖度由治理前的30%以下提高到70%以上,平均亩干草产量由30kg以下提高到90kg以上.     

草原沙化治理工程牧草补播的优点

为切实加强辽西北地区草原沙化治理，尽快提高沙化草原植被盖度，努力改善生态环境，全面推进生态辽宁建设，省委、省政府决定在辽西北土地沙化严重的县（市）实施草原沙化治理工程。2009-2013年，凌源市实施草原沙化治理工程50万亩（每亩667平方米）。根据工程设计要求，补播沙打旺、草木樨和苜蓿等豆科牧草36万亩，水泥立柱、刺线围栏1650千米。据报道，通过围栏封育、补播改良等综合措施治理，治理区草原植被盖度由30%以下提高到70%以上，亩产干草由30千克以下提高到90千克以上，初步遏制工程区草原沙化、荒漠化势头，生态环境明显改善，草原沙化治理工程取得预期效果。     

如何有效治理沙化草原

阜新蒙古族自治县位于辽宁省西北部,全县总土地面积62.47万hm2,其中天然草场15.6万hm2。虽然草原面积较大,但草场沙化严重。2009年前全县沙化草原面积近百万亩,严重破坏了生态环境,全县长期干旱多风沙,直接导致辽中平原生态环境质量下降。2009年开始,辽宁省政府开始实施辽西北草原沙化治理工程。在草原沙化治理过程中,主要采用了"围栏+补播"的治理模式。由于治理措施科学合理,加上后期管护得力,取得了很好的效果。     

草原沙化治理围封补播效果的研究

草原沙化治理主要是通过围栏封育、补播改良、治虫灭鼠等重要措施,来改变沙化草原植被状况,恢复草原生产力和生态功能,改善和提高草场等级.近几年,随着退耕还草、辽西北草原沙化治理工程以及封山禁牧的实施,草原沙化治理的面积逐年增加,但草原生态环境总体恶化的趋势尚未得到有效遏制.     

辽西北300万亩草原沙化治理工程区效果评价报告

为了推进辽宁"生态省"建设,加快实施"突破辽西北战略",辽宁省委省政府决定于2009年至2011年实施辽西北草原沙化治理一期工程,先行治理沙化草原300万亩,以阻止科尔沁沙地南侵,遏制辽西北生态恶化趋势。辽宁草原部门遵循植被演替规律,结合以往实践经验,提出对沙化、退化和荒漠化草原实施围栏封育、补播改良为主的技术路线。各级地方政府和草原部门高度重视、精心组织、科学实施、规范管理,工程开展仅3年,治理区植被盖度显著提高,初步打造出一条环科尔沁沙地南缘网状分布     

草原荒漠化的物理过程

综合了国内外的研究成果,详细说明了草原荒漠化的人为主要原因--开垦草原、过度放牧、滥采滥挖是如何导致草原荒漠化的.草原荒漠化的大体过程是:1)开垦草原、滥采滥挖→植被减少和表土露出→土壤风蚀、水蚀→土壤沙化、盐碱化;2)用地下水灌溉→造成土地盐碱化;3)过度放牧→植被减少→出现"秃斑" →"秃斑"扩大、蔓延→草原沙化、盐碱化.     

商会自治的基石——商会自治规范研究

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。     

癸氧喹酯干混悬剂含量测定的改进

采用高效液相色谱法测定癸氧喹酯干混悬剂的含量,在2-250μg/mL范围内,峰面积的常用对数与进样量浓度的常用对数呈良好的线性关系,R^2=1(n=5),平均回收率为99.24%~99.51%,RSD在0.05%~0.28%。此方法分析时间短,样品前处理简便、定量结果准确,重现性好,结果满意,为其质量控制提供了依据。     

猪毛色遗传的研究进展

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。     

Comparison of 2 methods of centesis of the bursa of the biceps brachii tendon of horses

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.     

不同样本商品蜂蜜中硒含量的测定

用硝酸和高氯酸消化蜂蜜,使硒游离出来,在微酸性环境下,硒和2,3-二氨基萘(DAN)生成有较强荧光的物质,用环己烷萃取,在激发波长378nm,荧光波长518nm处测定其荧光强度。蜂蜜中硒含量范围:0.10～0.82μg/g。表明:蜂蜜应视为天然富硒营养品。     

乳酸杆菌益生作用机制的研究进展

乳酸杆菌作为益生菌广泛用于人和动物。本文综述了乳酸杆菌改善宿主健康的机制。乳酸杆菌可通过产生抗菌物质如乳酸、过氧化氢、细菌素,或者通过竞争营养或肠道黏附位点来抑制致病菌;通过诱导黏附素的分泌或阻止细胞凋亡而增强肠道的屏障功能,从而保护肠道。文章重点讨论了乳酸杆菌表面成分（表面蛋白、脂磷壁酸和肽聚糖）与肠道受体（Ｃ型凝集素受体、Ｔｏｌｌ样受体和 Ｎｏｄ样受体）,阐述了他们结合后启动免疫调节信号,调控肠道免疫功能以发挥改善健康作用的机制。     

中华人民共和国农业部公告 第267号

为贯彻落实《兽药生产质量管理规范》(简称《兽药GMP》),进一步推动兽药GMP实施进程,我部制定了《兽药生产质量管理规范检查验收办法》,现予公告。本公告自2003年6月1日起施行。附件:兽药生产质量管理规范检查验收办法二○○三年四月十日第一章 总则 第一条 为推动《兽药生产质量管理规范》(以下简称兽药GMP)的实施,规范兽药GMP检查验收工作,制定本办法。 第二条 农业部负责全国兽药GMP管理和检查验收工作;负责制修订兽药GMP检查验收管理规定;负责兽药GMP检查员队伍建设和监督管理工作,负责国际兽药贸易中GMP互认工作。 …     

鸡败血支原体垂直传播模式及其阻断方法

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。     

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.