Dung application increases CH<Subscript>4</Subscript> production potential and alters the composition and abundance of methanogen community in restored peatland soils from Europe

Peatland restoration via rewetting aims to recover biological communities and biogeochemical processes typical to pristine peatlands. While rewetting promotes recovery of C accumulation favorable for climate mitigation, it also promotes methane (CH₄) emissions. The potential for exceptionally high emissions after rewetting has been measured for Central European peatland sites previously grazed by cattle. We addressed the hypothesis that these exceptionally high CH₄ emissions result from the previous land use. We analyzed the effects of cattle dung application to peat soils in a short- (2 weeks), a medium- (1 year) and a long-term (grazing) approach. We measured the CH₄ production potentials, determined the numbers of methanogens by mcrA qPCR, and analyzed the methanogen community by mcrA T-RFLP-cloning-sequencing. Dung application significantly increased the CH₄ production potential in the short- and the medium-term approach and non-significantly at the cattle-grazed site. The number of methanogens correlated with the CH₄ production in the short- and the long-term approach. At all three time horizons, we found a shift in methanogen community due to dung application and a transfer of rumen methanogen sequences (Methanobrevibacter spp.) to the peatland soil that seemed related to increased CH₄ production potential. Our findings indicate that cattle grazing of drained peatlands changes their methanogenic microbial community, may introduce rumen-associated methanogens and leads to increased CH₄ production. Consequently, rewetting of previously cattle-grazed peatlands has the potential to lead to increased CH₄ emissions. Careful consideration of land use history is crucial for successful climate mitigation with peatland rewetting.     

澳大利亚畜牧业概况

澳大利亚现有绵羊 1 2 3亿只 ,牛 2 60 0万头 ,草食动物养殖规模化程度很高。畜牧业成功之路在于引进欧洲及地中海草种 ,人工种植牧草 ,以及改良或引进生产性能优良的动物品种。动物活体及其产品出口是促进畜牧业稳步发展的重要因素     

强优势组合选配的几个关键问题 简报·简讯

利用化学杀雄剂生产小麦杂交种,是杂种小麦尽快应用于生产的有效的途径之一。而这一技术的关键是强优势组合的选配。目前小麦杂优利用普遍存在着杂种产量不能显著超亲或超标;杂种株高偏高造成高产栽培易发生倒伏;一些强优组合往往父母本花期不能相遇的问题。另外缺乏一个综合农艺性状较好的亲本。本实验通过对小麦杂交组合杂种一代的产量、株高、穗粒数、千粒重等性状的杂交优势及杂交双亲的花期重叠情况进行测定,分析发现:杂交种的杂种优势主要表现在株高和千粒重上。因此,在强优势组合选配时,亲本应充分利用大粒或超大粒材料。从组合类型看:母本应选用矮杆、大穗大粒或超大粒型综合农艺性     

赴美森林火灾扑救指挥系统培训考察报告

2008年5月12日-5月24日,由美国路易斯安那州立大学教授Sun Joseph Chang博士陪同,南京森林公安高等专科学校948项目赴美国培训考察团一行三人在美国加州学习和考察了森林火灾扑救指挥系统(ICS)及其培训体系,并观摩了ICS实     

和美酵素代替油脂对矮小型蛋鸡生产性能的影响

用4种饲料在冬季饲养矮小型蛋鸡,A组为对照组,使用不加油或和美酵素的基础日粮;B组日粮是基础日粮添加0.5%油脂和500g/T和美酵素;C组日粮是基础日粮添加油脂;D组日粮是在基础日粮基础上加500g/T和美酵素,实验期11周。结果表明,使用基础日粮加和美酵素的D组产蛋率最高穴77.7%雪,和其它3个组差异显著(P<0.05雪,实验期料蛋比2.21押1熏每只鸡毛利3.52元,比对照组和加油组分别高0.45元和0.79元。结果也表明熏在代谢能较高的饲料中添加和美酵素,会使矮小型鸡的体重显著增加,并不能显著提高产蛋水平,因此和油脂同时使用效果不好。     

农业电子词库及其管理系统的结构与特点

本文介绍了“农业信息机译系统研究”一期工程－“农业电子词库及其管理系统”的缘起、结构与特点。     

用SSR标记提高水稻分子连锁图谱密度

本课题组利用圭630／台湾粳的DH群体，建立了一个水稻RFLP连锁图。该图谱含175个标记，总长1224．6cM，相邻标记间平均距离为7．0cM。但该图标记分布不够均匀，存在较多空白区，且在第4和第8染色体上分别存在一个断点。本研究试图在原有RFLP图谱的基础上，添加一些SSR标记，以使该图谱标记更加密集和均匀，并消除两个断点。共筛选了361对RM引物，获得了183对多态标记，在12条染色体上共整合了57个RM标记，染色体连锁图总长度为1811．2cM，比原图谱增长了47．9％，相邻标记间平均距离为7．8cM，与原图谱相近。不过，两条染色体上的两个断点仍无法消除，暗示这两个断点区域多态性较低或重组率较高。     

Computed tomographical (CT) anatomy of the thoracoabdominal cavity of the male turkey (Meleagris gallopavo)

In the present work, our goal was to match high-resolution computed tomography (CT) scans with cross-sectional anatomical pictures of the turkey (Meleagris gallopavo). Two male BUT 6 (a commercial line) turkeys were used. CT scans with 1 mm slice thickness were performed. The images covered the trunk from the level of the 9th cervical vertebra to the end of the coccyx. The anatomical sections and the CT scans were matched, and the important structures were identified and labelled on the corresponding pictures. The aim of this study was to create a reference for evaluating CT scans of avian species.