1000 resultados para North Dakota


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"Sponsored by the North Dakota Institute for Regional Studies."

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"Other Publications on plants": p. 52.

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Reprinted from The American midland naturalist, v. 4-5, 1915-1917.

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The Bakken region of North Dakota and Montana has experienced perhaps the greatest effects of increased oil and gas development in the United States, with major implications for local governments. Though development of the Bakken began in the early 2000s, large-scale drilling and population growth dramatically affected the region from roughly 2008 through today. This case study examines the local government fiscal benefits and challenges experienced by Dunn County and Watford City, which lie near the heart of the producing region. For both local governments, the initial growth phase presented major fiscal challenges due to rapidly expanding service demands and insufficient revenue. In the following years, these challenges eased as demand for services slowed due to declining industry activity and state tax policies redirected more funds to localities. Looking forward, both local governments describe their fiscal health as stronger because of the Bakken boom, though higher debt loads and an economy heavily dependent on the volatile oil and gas industry each pose challenges for future fiscal stability.

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Increases in oil prices after the economic recession have been surprising for domestic oil production in the United States since the beginning of 2009. Not only did the conventional oil extraction increase, but unconventional oil production and exploration also improved greatly with the favorable economic conditions. This favorable economy encourages companies to invest in new reservoirs and technological developments. Recently, enhanced drilling techniques including hydraulic fracturing and horizontal drilling have been supporting the domestic economy by way of unconventional shale and tight oil from various U.S. locations. One of the main contributors to this oil boom is the unconventional oil production from the North Dakota Bakken field. Horizontal drilling has increased oil production in the Bakken field, but the economic issues of unconventional oil extraction are still debatable due to volatile oil prices, high decline rates of production, a limited production period, high production costs, and lack of transportation. The economic profitability and viability of the unconventional oil play in the North Dakota Bakken was tested with an economic analysis of average Bakken unconventional well features. Scenario analysis demonstrated that a typical North Dakota Bakken unconventional oil well is profitable and viable as shown by three financial metrics; net present value, internal rate of return, and break-even prices.

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The North Central Risk Management Education Center has been providing program coordination for extension risk management education in the North Central Region since 2001. During this time, nearly five million dollars has been awarded to public, private and non-profit entities to carry out producer-focused, results-based risk management education programs. The North Central Region includes Illinois, Indiana, Iowa, Kansas, Michigan, Minnesota, Missouri, Nebraska, Ohio, North Dakota, South Dakota and Wisconsin.

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In North America there are two generally recognized pathotypes (pathotypes 1 and 2) of the fungus Entomophaga grylli which show host-preferential infection of grasshopper subfamilies. Pathotype 3, discovered in Australia, has a broader grasshopper host range and was considered to be a good biocontrol agent. Between 1989 and 1991 pathotype 3 was introduced at two field sites in North Dakota. Since resting spores are morphologically indistinguishable among pathotypes, we used pathotype-specific DNA probes to confirm pathotype identification in E. grylli-infected grasshoppers collected at the release sites in 1992, 1993, and 1994. In 1992, up to 23% of E. grylli-infected grasshoppers of the subfamilies Melanoplinae, Oedipodinae, and Gomphocerinae were infected by pathotype 3, with no infections > 1 km from the release sites. In 1993, pathotype 3 infections declined to 1.7%. In 1994 grasshopper populations were low and no pathotype 3 infections were found. The frequency of pathotype 3 infection has declined to levels where its long-term survival in North America is questionable. Analyses of biocontrol releases are critical to evaluating the environmental risks associated with these ecological manipulations, and molecular probes are powerful tools for monitoring biocontrol releases.

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"Agricultural experiment stations of Alaska, Illinois, Indiana, Iowa, Kansas, Michigan, Minnesota, Missouri, Nebraska, North Dakota, Ohio, South Dakota, Wisconsin, and the U.S. Department of Agriculture, cooperating."

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"The research on which this report is based was undertaken as part of the North Central Regional Poultry Marketing Project NCM-14."--P. [3].

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"Cooperative extension services of North Dakota [and others] and the U.S. Dept. of Agriculture cooperating."

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Semi-dwarfing genes have been widely used in spring barley (Hordeum vulgare L.) breeding programs in many parts of the world, but the success in developing barley cultivars with semi-dwarfing genes has been limited in North America. Exploiting new semi-dwarfing genes may help in solving this dilemma. A recombinant inbred line population was developed by crossing ZAU 7, a semi-dwarf cultivar from China, to ND16092, a tall breeding line from North Dakota. To identify quantitative trait loci (QTL) controlling plant height, a linkage map comprised of 111 molecular markers was constructed. Simple interval mapping was performed for each of the eight environments. A consistent QTL for plant height was found on chromosome 7HL. This QTL is not associated with maturity and rachis internode length. We suggest the provisional name Qph-7H for this QTL. Qph-7H from ZAU 7 reduced plant height to about 3/4 of normal; thus, Qph-7H is considered a semi-dwarfing gene. Other QTLs for plant height were found, but their expression was variable across the eight environments tested.

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Contains Deed of Trust, By-Laws, Annual Reports, Corporation Minutes (1909, 1913-1919, 1923-1924, 1926-1933), Minutes of the Board of Trustees (1893, 1899, 1907, 1910, 1915-1916, 1918, 1923, 1926-1927, 1930-1933), and the minutes, correspondence, and reports of the various national and local committees. Financial materials include income and expenditure records (1891-1933), audits (1919-1923, 1926-1928), the records of agricultural loans and mortgages, bond and real estate holdings, and bequests. Includes also correspondence and other materials regarding the establishment of the Fund, correspondence of and other papers concerning the Baron and Baroness de Hirsch, and several histories of the Fund. Included in the wide range of activities are material on the work of the Agriculture Bureau and the Jewish Agriculture Society, Housing, English Classes, Immigration (including monthly reports for several ports of entry 1885-1916) and Immigrant Aid, German Refugee Aid in the early years of the Holocaust, Kings Park, N.Y. Test Farm, the Laundry Project, Peekskill Farm, Public Baths, Student Loans, the Baron de Hirsch Trade School, and the Woodbine Colony and Baron De Hirsch Agricultural & Industrial School. Contains also materials on the Colonization attempts made in Colorado, Connecticut, Florida, Louisiana, Michigan, Minnesota, North Dakota, New Jersey, New York, Pennsylvania, South Dakota, Galveston, Texas, The Southwest, Washington, Canada, and Mexico.

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陆地植物起源以后,地球上的环境发生了巨大的变化。大气CO2浓度自泥盆纪早期的2000-4OOOμml•mol_1下降至石炭一二叠纪的300μml•mol_1左右,02浓度在泥盆纪至石炭一二叠纪时期,由20-30μml•mol_1上升到70-80μml•mol_1,随后又下降到目前的水平。陆地植物登陆后,形态结构也发生了显著的改变,气生部分表而分化出了通气结构--气孔器和保护结构--角质层。泥盆纪首选标志植物刺镰蕨(Drelpanophycus spinaefrmis)在整个泥盆纪,广布全世界。刺镰蕨的气孔器类型一直存在两种观点,一种认为刺镰蕨的气孔器是平列型,即气孔器山两个保卫细胞和两个副卫细胞组成:另一观点认为刺镰蕨的气孔器为不规则型,即气孔器仅有两个保卫细胞构成,不具副卫细胞。我们借助于扫描电镜、石蜡制片技术和叶表皮离析法,细致地研究了现代石松(Lycopodium japonicum)叶的横切而、表皮及气孔器的内外表面结构,并同刺镰蕨的表皮和气孔器进行了对比。认为刺镰蕨的气孔器和所有的化石石松类及现代石松类的气孔器一样,均属于不规则型。从而解决了关于刺镰蕨气孔器类型的长期争论的关键性科学问题。 胡桃科青钱柳属植物起源于晚白垩世的环北太平洋沿岸,化石植物最早发现于北美古新世和早始新世的Motana,,Wyoming,North Dakotanorth Colorado地区,欧亚地区仅出现在渐新世至上新世的Kazakhstan、Germany、Romnania、Russia、Japan、中国云南远谋和四川米易地区。我们将采于吉林省珲春组始新世的叶化石鉴定为一青钱柳相似种,该化石成为东亚地区出现最早的青钱柳属植物,这一发现也支持晚白垩至早第三纪时期环北太平洋两岸曾经相连的观点,青钱柳属在晚白垩由北美起源,在始新世经东亚向欧亚大陆扩散,由于环境变迁,第四纪以后,青钱柳属仪剩一种植物分布于中国的亚热带地区。文中还利用共存分析方法估测出始新世吉林省珲春地区属于暖温带至亚热带气候。 统万城遗址位于我国黄土高原向毛乌素沙漠过渡地带的北缘,属于暖温带森林草原向温带干草原、温带荒漠草原过渡的地区,同时又是东部季风区向西北干旱区过渡的生态环境敏感带。今天统万城地区的自然景观属于沙漠,仅存稀疏的次生灌丛和草本群落。但是,通过对统万城城墙内的孢粉和木材进行的综合研究表明,在约1600年前,当地为温带草原,在塬面或山丘上分布有侧柏林,沟谷、河岸边生长喜温湿的乔木,河流、湖泊、沼泽中水生植物繁盛,在丘间低洼处或盐碱土上分布有灌木和草本植物。当时该地区的年均温为7.8 ℃-9.3℃,最热月平均温度23.0℃-24.9℃,最冷月平均温度-12℃-5.6℃,年较差28.5℃-3 8.2℃,年降雨量403.4-550.Omm,最大月降雨量83.8-123.9mm,最少月降雨量4.4-12.2mm,当时气候比现在温暖湿润,年均温比现在高出0.2-0.7℃,年降雨量也高出60--lOOmm。而如此的历史景观今天已经向南迁移,侧柏林或森林草原退缩至延安以南地区。在此近1600年的时间里,毛乌素沙漠分布范围不断扩大,其南部边缘推进了约200 km,推测沙漠扩展的速率达到平均125m/a。

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草地退化不仅仅是今天中国才发生的事情。历史上曾经发生“黑尘暴”的美国North Dakota州,现在仍然有62.7%土地被用作耕作,林地所占面积仅仅占1%。私有制和种植业较畜牧业的高的利润率,是该州种植业比重高于畜牧业的重要原因。草原保护项目(CRP)得到了美国政府财政的大力支持, 在North Dakota州采用了以草地恢复为主的措施。美国发达的教育体系带来的高流动率,使得North Dakota州自30年代后居住人口稳定在60-70万成为可能,从而避免了我国出现的草原地区不断增加的人口压力。由此可见:草地作为重要的自然资源,不可能完全保护起来;没有其他配套措施,私有制可能会带来新一轮垦殖;草地畜牧业仍然是畜牧业的重要组成部分,畜牧业发展需要结合种植业尤其需要与饲料生产相结合。 依据生态系统服务的理念,首次发展了生态系统服务指数(ESI),试图通过对生态系统服务功能的综合考虑,提出科学的适宜放牧率的评价方法。本文利用美国北达科他州立大学中部草原研究站17年长期放牧试验数据,选取植物多样性Shannon-Wiener指数、地上净初级生产力、土壤表层含水量和单位面积家畜增重等四个指标,通过对不同指标分别赋予不同的权重,计算不同管理目标下ESI及其稳定性,并对单目标管理与多目标管理进行了比较研究。结果表明,对于北美混合普列里(Prairie)草地,围封不利用或建立自然保护区,虽然生态系统比较稳定,但既不能有效的提高植物多样性、初级生产力和土壤水分含量等生态功能,又没有畜产品产出;而在重牧或极重牧处理下虽然获得了较大的畜产品生产,但导致了草地生态系统的退化和较大的系统不稳定性。因此,这两种管理方式在实践中都是不可取的。应用生态系统服务指数综合考虑,认为应该权衡各项生态功能和生产功能,此时轻牧或中牧是最适宜的。因此,ESI的建立避免了单项指标的评价偏差,使得适宜放牧率的确定更加合理。 利用前面构建的多目标权重评价体系,结合内蒙古草原生态系统定位站放牧试验样地的数据,探讨了锡林郭勒盟定位站附近的适宜放牧率为2.67羊/ha,低于单目标条件下的每公顷绵羊4羊/ha。同时在经济学和生态系统系统服务理论的基础上,依据谢高地等人(2001年)的研究,并提出了环境税和生态补偿的标准,分别是每公顷15元和90元。