内蒙古大兴安岭林区发展草地畜牧业潜力分析与对策

内蒙古大兴安岭林区草地资源较为丰富，发展林区草地畜牧业的潜力较大，但该地区草地资源和利用不均衡，有的草地严重超载，造成草场退化；而有此可利用草地尚未被充分利用，本文着重对充分利用的区域和自然条件优势及丰富的草地资源，发展林区畜牧业，建立绿色畜产品基地的潜力和对策，进行了切实可行的分析。     

我国西北地区牧草种子生产现状及存在问题浅析

调查了牧草种子生产现状及存在问题。结果表明：我国西北地区的栽培牧草包括豆科、禾本科、藜科、菊科、苋科、紫草科、十字花科、鸢尾科等９科３６属５３种。其中：豆科牧草１３属２１种；禾本科牧草１６属２５种；其它科牧草７属７种。该区栽培牧草总面积约为１５０万ｈｍ＾２，其中主要豆科牧草占７１％，主要禾本科牧草占１０．５％。主要豆科牧草为紫花苜蓿、沙打旺、草木樨、箭舌豌豆、红豆草、柠条和小冠花。主要禾本科牧草为     

森林旅游资源的分级

为正确反映森林旅游资源系统的本质和客观差异,将森林旅游资源分为4个层次、6个项目、26个要素.以200分为总分,按各要素的权重系数分配各要素的赋分值,所得总高分高于171分为一级;161～170分为二级,以此类推,低于90分为十级,共分为10级.最后对9个森林旅游区的森林旅游资源进行了评价与分级.     

对退耕还林还草有关问题的进一步思考

阐述了“一退双还”政策措施提出的意义和实施情况,提出应进一步明确“一退双还”的目的,从思想和政策上解决重林木轻草灌的倾向,力戒形式主义和表面文章、讲求实绩实效,“以林为主”的绿化方针值得进一步深思和商榷,“一退双还”的责任制和利益机制需进一步完善等一系列问题,值得进一步深入思考和认真解决,以保证“一退双还”和国土绿化工作的持续和健康发展。     

Scale dependence of tree abundance and richness in a tropical rain forest,Malaysia

Abundance and richness are the two fundamental components of speciesdiversity. They represent two distinct types of variables of which the formerisadditive when aggregated across scales while the latter is nonadditive. Thisstudy investigated the changes in the spatial patterns of abundance andrichnessof tree species across multiple scales in a tropical rain forest of Malaysiaandtheir variations in different regions of the study area. The results showedthatfrom fine to coarse scales abundance had a gradual and systematic change inpattern, whereas the change in richness was much less predictable and ahotspot in richness at one scale may become acoldspot at another. The study also demonstrated that differentmeasures of diversity variation (e.g., variance and coefficient of variation)can result in different or even contradictory results which further complicatedthe interpretation of diversity patterns. Because of scale effect the commonlyused measure of species diversity in terms of unit area (e.g.,species/m²) is misleading and of little use in comparing speciesdiversitybetween different ecosystems. Extra care must be taken if management andconservation of species diversity have to be based on information gathered at asingle scale.This revised version was published online in May 2005 with corrections to the Cover Date.     

内蒙古黄河上中游天然林资源保护工程区立地条件分析

文章通过对自治区黄河上中游“天保”工程区的自然条件分析和立地类型划分 ,提出了恢复植被 ,控制水土流失 ,减轻风沙危害的具体措施。根据工程区不同的立地类型 ,采取乔、灌、草相结合的不同模式 ,最大限度的增加植被盖度 ,从而达到改善生态环境的目的。     

暖季放牧犊牦牛对高寒草甸地区人工草地的影响

为更好地了解青藏高原高寒草甸区暖季放牧条件下人工草地牧草的生长特点,为制定合理放牧制度提供依据,于2001~2003年开展了暖季放牧牦牛对多年生人工草地影响的试验。结果表明:放牧2年后轮牧人工草地播种牧草比例为95.27%,连续放牧人工草地为86.15%,无放牧人工草地为58.01%。轮牧人工草地牧草月风干重最高值3 198.8 kg/hm2,连续放牧人工草地为3 023.2 kg/hm2。放牧可以提高人工草地牧草生长率,轮牧人工草地的牧草生长率高于连续放牧人工草地。放牧还影响着第2年播种牧草的生长,轮牧能促进种子出苗数,播种牧草的鲜重,风干重和种子产量分别达到了5 088.88 kg/hm2,3 053.33 kg/hm2和480 kg/hm2,均高于连续放牧人工草地和无放牧草地,轮牧人工草地杂草鲜草产量最低,为193.33 kg/hm2。适宜的放牧是保持人工草地可持续利用的手段之一。     

Reproductive and productivity traits of goats grazing Acacia cyanophylla Lindl. with and without daily PEG supplementation

A grazing experiment, conducted for 90 days compared the effect of polyethylene glycol (PEG) supplementation on postpartum reproductive traits and productivity of suckling goats grazing Acacia cyanophylla Lindl. A total of 54 native adult goats (34.4 ± 5.49 kg) were randomly allocated, 24 h after kidding, to 2 treatment groups balanced for age and the number of reared kids. Goats in both treatment groups designed C and PEG grazed in acacia for approximately 5 h every day and received each on daily basis 0.3 and 0.4 kg of hay and concentrate respectively. In addition, goats in treatment PEG were initially supplemented with 10 g/day of PEG and this supplement was then increased to 20 g /goat/day over the last 60 days of the trial. Goats receiving PEG tended (P > 0.05) to spend more time browsing acacia than those in treatment C. There were no treatment effects on live weight change of the goats, growth of their kids until 90 days of age or composition of their milk in terms of fat, protein and urea contents. Similar proportions of 74.1 and 77.8% of goats resumed postpartum ovulation with a mean ovulation rate of 1.50 ± 0.61 and 1.67 ± 0.47 (P > 0.05) in respectively the PEG and C treatments. PEG supplementation was associated with an increase (P < 0.05) in ovulation rate at the second postpartum ovulation occurring approximately 27 days after the application of the nutritional treatments (1.76 ± 0.60 versus 1.25 ± 0.45); 9 of the 13 goats ovulating in the PEG treatment were bearing more than one corpus lutuem in comparison to only 3 out of 12 females in the C group (P < 0.05). The likely increased availability of proteins in the PEG receiving goats could explain their higher ovulation rate.     

Xylitol intoxication associated with fulminant hepatic failure in a dog

Objective: To describe a case of xylitol intoxication causing fulminant hepatic failure in a dog. Case summary: A 2.5‐year‐old castrated male English Springer Spaniel weighing 26 kg, was presented after ingestion of half of a loaf of bread containing the sweetener xylitol. Toxic effects of the xylitol in this dog included vomiting, mild hypoglycemia and fulminant hepatic failure. Clinical management of acute hepatic failure and subsequent coagulopathy with supportive care and fresh frozen plasma is described. The dog was discharged 3 days after admission after a full clinical recovery. New or unique information provided: This paper describes the clinical consequence and successful treatment of fulminant hepatic failure in a dog following ingestion of xylitol.     

纤维素酶对粗饲料人工瘤胃pH、氨态氮及产气量的影响

本试验分别以棉籽壳、苜蓿、小麦秸秆、玉米青贮、玉米秸秆为底物,采用人工瘤胃技术,研究不同水平纤维素酶对人工瘤胃pH、氨态氮浓度及产气量的影响。对照组未添加纤维素酶,试验1、2和3组分别添加纤维素酶140、280、420IU/mL。结果表明,不同水平纤维素酶的人工瘤胃pH无显著变化(P>0.05),氨态氮浓度变化不显著(P>0.05),但人工瘤胃最大产气量显著提高(P<0.05)。