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美国North Dakota州土地利用研究及对我国草地利用的启示
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作者 潘绪斌 汪诗平 +2 位作者 Paul Nyren Bob Patton Anne Nyren 《广西植物》 CAS CSCD 北大核心 2010年第2期196-201,共6页
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Nort hDakota州,现仍有62.7%土地被用作耕作,林地所占面积仅为1%。私有制以及种植业较高的利润率,是该州种植业比重高于畜牧业的重要原因。草原保护项目(... 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Nort hDakota州,现仍有62.7%土地被用作耕作,林地所占面积仅为1%。私有制以及种植业较高的利润率,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,从而避免了中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;没有其它配套措施,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。 展开更多
关键词 NORTH Dakota 土地利用 农业生产 产权制度 CRP
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Quantifying Spatiotemporal Change in Landuse and Land Cover and Accessing Water Quality: A Case Study of Missouri Watershed James Sub-Region, North Dakota 被引量:2
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作者 Papia F. Rozario Peter Oduor +1 位作者 Larry Kotchman Michael Kangas 《Journal of Geographic Information System》 2016年第6期663-682,共20页
Spatial causal effects on water quality are essential in identification of vulnerable watersheds. Modelling landuse variables is an effective method of projecting localized impairment. This study presents an integrate... Spatial causal effects on water quality are essential in identification of vulnerable watersheds. Modelling landuse variables is an effective method of projecting localized impairment. This study presents an integrated index, designed to gauge the ability of an 8-digit Hydrologic Unit Code watershed in its ability to produce clean water. This index, I<sub>APCW</sub>, can be successfully applied on a geospatial platform. In this study we utilized I<sub>APCW</sub> to address forest cover dynamics of an impaired watershed, that is, Missouri Watershed James Sub-region in North Dakota. Specific parametric functions were analysed and combined within a customized GIS interface to provide a multi-faceted structured technique to derive I<sub>APCW</sub>. These included ambient forest cover, housing density, agricultural land, soil erodibility and road density;it can be lucidly ascertained that where a prevailing forest cover undergoes conversion processes, the secondary effect may spur an exponential increase in water treatment costs. These parameters when projected statistically validated temporal and spatial relations of landuse/land cover dynamics to nutrient concentrations especially those that would be noted at the mouth of the watershed. In this study, we found that the levels of Total Dissolved Solids (TDS) were much higher for the years 2014 to 2016 with a discernible increased alkalizing effect within the watershed. When I<sub>APCW</sub> was compared to Annualized Agricultural Nonpoint Source (AnnAGNPS), the spatial distribution generated by the AnnAGNPS study showed that fallow areas produced significant amounts of sediment loads from the sub-watershed. These same locations in this study generated a low I<sub>APCW</sub>. 展开更多
关键词 Spatial Analyst Index of Ability to Produce Clean Water LANDUSE Water Quality
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Forecasting Oil Production in North Dakota Using the Seasonal Autoregressive Integrated Moving Average (S-ARIMA) 被引量:1
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作者 Jaesung Choi David C. Roberts EunSu Lee 《Natural Resources》 2015年第1期16-26,共11页
North Dakota’s oil production has been rapidly increasing during the past several years. The state’s oil production in March 2013 even increased to more than twice the quantity produced in March 2011, and the estima... North Dakota’s oil production has been rapidly increasing during the past several years. The state’s oil production in March 2013 even increased to more than twice the quantity produced in March 2011, and the estimated Bakken Formation reserves were reported very large compared with those of the United Arab Emirates. It eventually makes a question to us of how much oil will be able to be actually extracted with currently available technologies. To answer this question, this paper forecasts future oil development trend in North Dakota using the Seasonal Autoregressive Integrated Moving Average (S-ARIMA) model. Nonstationarity derived from a stochastic trend and the abrupt structural change of oil industry was a big potential problem, but through the Quandt Likelihood Ratio test, we found break points, which allowed us to select a model fitting period suitable for the S-ARIMA method to provide accurate statistical inference for the historical period. The seven major oil producing counties were investigated to determine whether the current oil boom was consistent across all oil fields in North Dakota. Empirical estimates show that North Dakota’s oil production will be more than double in the next five years. What we can predict with great certainty is that North Dakota’s influence over domestic and global oil supply systems will increase in the near future, especially over the next five to six years. This is good news for those who are concerned about domestic energy security in the USA. 展开更多
关键词 Bakken FORMATION Forecasting NORTH Dakota OIL S-ARIMA
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Market Information on Sourcing Cellulosic Feedstock for Biofuel Production in Northern Plains Region of the United States
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作者 Thein A. Maung Cole R. Gustafson +2 位作者 David M. Saxowsky Tatjana Miljkovic John F. Nowatzki 《Journal of Agricultural Science and Technology(A)》 2012年第1期10-23,共14页
关键词 市场信息 生物燃料 平原地区 原料生产 纤维素 作物残茬 动力供应 采购
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Impact of Climate Variability on Yield of Spring Wheat in North Dakota
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作者 Ganesh C. Bora Sukhwinder Bali Purbasha Mistry 《American Journal of Climate Change》 2014年第4期366-377,共12页
Agricultural production is highly dependent on the climatic variability of the specific regions. Differential climatic and soil conditions bring about changes in yield, quality of crops thus affecting the economy. Thi... Agricultural production is highly dependent on the climatic variability of the specific regions. Differential climatic and soil conditions bring about changes in yield, quality of crops thus affecting the economy. This study evaluated the impact of variability in different climatic factors keeping the other factors constant on spring wheat production in North Dakota from 2007 to 2011. The spring wheat yield mainly depends on the climatic changes during growing periods April to September. Average maximum air temperature was significantly different from April to September except June from 2007 to 2011. High average minimum and maximum air temperatures during planting time increase yield and planting area for 2010. In 2011, low mean soil temperature, excess rainfall in April caused low yield of spring wheat. The unmitigated climate variability will result in declines in yields. So, adoption of sustainable agriculture practices helps the farmers to develop the different practices for their farms. 展开更多
关键词 Climate VARIABILITY CROP Production NORTH Dakota Spring WHEAT
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Uncertainty Analysis of Spatial Autocorrelation of Land-Use and Land-Cover Data within Pipestem Creek in North Dakota
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作者 Papia F. Rozario Peter G. Oduor +1 位作者 Larry Kotchman Michael Kangas 《Journal of Geoscience and Environment Protection》 2017年第8期71-88,共18页
A major threat to biodiversity in North Dakota is the conversion of forested land to cultivable land, especially those that act as riparian buffers. To reverse this trend of transformation, a validation and prediction... A major threat to biodiversity in North Dakota is the conversion of forested land to cultivable land, especially those that act as riparian buffers. To reverse this trend of transformation, a validation and prediction model is necessary to assess the change. Spatial prediction within a Geographic Information System (GIS) using Kriging is a popular stochastic method. The objective of this study was to predict spatial and temporal transformation of a small agricultural watershed—Pipestem Creek in North Dakota;USA using satellite imagery from 1976 to 2015. To enhance the difference between forested land and non-forested land, a spectral transformation method—Tasseled-Cap’s Greenness Index (TCGI) was used. To study the spatial structure present in the imagery within the study period, semivariograms were generated. The Kriging prediction maps were post-classified using Remote Sensing techniques of change detection to obtain the direction and intensity of forest to non-forest change. TCGI generated higher values from 1976 to 2000 and it gradually reduced from 2000 to 2011 indicating loss of forested land. 展开更多
关键词 KRIGING Tasseled CAP Greenness Index Land-Use and LAND-COVER
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Transition Modeling of Land-Use Dynamics in the Pipestem Creek, North Dakota, USA
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作者 Papia F. Rozario Peter Oduor +1 位作者 Larry Kotchman Michael Kangas 《Journal of Geoscience and Environment Protection》 2017年第3期182-201,共20页
Significant land-use changes in North Dakota have been reported and are widespread over the entire state. Such changing patterns may portend localized impairment to agricultural watersheds. In this study, Land-use Lan... Significant land-use changes in North Dakota have been reported and are widespread over the entire state. Such changing patterns may portend localized impairment to agricultural watersheds. In this study, Land-use Land-cover (LULC) change was modeled using geostatistics. The study area was within the Pipestem Creek watershed, a part of the Missouri Watershed James Subregion of North Dakota, USA. Landsat Thematic mapper images from the years 2007, 2011 and 2015 were used as preliminary data. LULC information for these datasets was acquired from the Global Land-cover facility and Landsat Program. Data analysis, spectral classification and post classification techniques were applied on the datasets. A transition matrix was derived using a Markov chain Monte Carlo (MCMC) model. This study demonstrates that the integration of satellite remote sensing, GIS and statistics may be an effective approach for analyzing the direction, rate, and spatial pattern of land-use change. 展开更多
关键词 MARKOV CHAIN LULC CHANGE TRANSITION Probabilities
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Prevalence of Mycotoxins in Late-Season Corn Ear Molds in North Dakota
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作者 Joel Ransom Kasia Kinzer +3 位作者 Marcia McMullen Michelle Mostrom Itai Mutukwa Andrew Friskop 《American Journal of Plant Sciences》 2016年第5期709-714,共6页
Widespread corn ear mold development in North Dakota and in other states was associated with cool, wet weather after physiological maturity in 2009. In response to concerns about possible grain mold and mycotoxin cont... Widespread corn ear mold development in North Dakota and in other states was associated with cool, wet weather after physiological maturity in 2009. In response to concerns about possible grain mold and mycotoxin contamination in North Dakota, a survey of corn ear diseases was conducted in 2009 prior to harvest. Corn ears were collected from 94 field locations from 24 counties and were examined macroscopically and microscopically for mold identification. Mycotoxin testing was done with a screen for 17 tricothecenes using gas chromatography/mass spectrometry techniques. Cladosporium was the most commonly identified fungus with some Fusarium contaminated samples being observed. Other fungi identified include Alternaria, Penicillium, Aureobsidium, Rhizopus, Stemphylium and an unidentified non-pigmented fungus. Five mycotoxins were identified in 25 out of the 94 samples;deoxynivalenol, T-2, HT-2, zearalenone and nivalenol. Of the mycotoxin-positive samples, 88% had less than 2 ppm of any mycotoxin. Despite the growing season’s weather being favorable for corn ear mold development late in the season, observed mycotoxin levels were surprisingly low and most grain was deemed safe for use in food and feed channels. Surveys were planned in subsequent years, but late season molds did not develop in the 2010-2015 growing seasons. 展开更多
关键词 DEOXYNIVALENOL Disease Survey Corn Diseases Ear Rots
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Higher Education on Building Energy and Sustainability in North Dakota
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作者 Huojun Yang Malini Srivastava Yanmei Xie 《Journal of Energy and Power Engineering》 2016年第9期540-544,共5页
关键词 可持续发展 建筑能源 高等教育 北美 能源消费 室内环境 半干旱草原 能源消耗
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Phytoremediation Strategies for Heavy Metal Contamination: A Review on Sustainable Approach for Environmental Restoration
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作者 Mariam Salifu Matthew Abu John +3 位作者 Murtala Abubakar Ibukunoluwa Abimbola Bankole Nneka Damola Ajayi Olawumi Amusan 《Journal of Environmental Protection》 2024年第4期450-474,共25页
Current globalization trends and important breakthroughs globally need a complete study of heavy metal contamination, its causes, its impacts on human and environmental health, and different remediation strategies. He... Current globalization trends and important breakthroughs globally need a complete study of heavy metal contamination, its causes, its impacts on human and environmental health, and different remediation strategies. Heavy metal pollution is mostly produced by urbanization and industry, which threatens ecosystems and human health. Herein, we discuss a sustainable environmental restoration strategy employing phytoremediation for heavy metal pollution, the carcinogenic, mutagenic, and cytotoxic effects of heavy metals such as cadmium, copper, mercury, selenium, zinc, arsenic, chromium, lead, nickel, and silver, which may be fatal. Phytoremediation, which was prioritized, uses plants to remove, accumulate, and depollute pollutants. This eco-friendly method may safely collect, accumulate, and detoxify toxins using plants, making it popular. This study covers phytostabilization, phytodegradation, rhizodegradation, phytoextraction, phytovolatilization, and rhizofiltration. A phytoremediation process’s efficiency in varied environmental circumstances depends on these components’ complex interplay. This paper also introduces developing phytoremediation approaches including microbe-assisted, chemical-assisted, and organic or bio-char use. These advancements attempt to overcome conventional phytoremediation’s limitations, such as limited suitable plant species, location problems, and sluggish remediation. Current research includes machine learning techniques and computer modeling, biostimulation, genetic engineering, bioaugmentation, and hybrid remediation. These front-line solutions show that phytoremediation research is developing towards transdisciplinary efficiency enhancement. We acknowledge phytoremediation’s promise but also its drawbacks, such as site-specific variables, biomass buildup, and sluggish remediation, as well as ongoing research to address them. In conclusion, heavy metal pollution threatens the ecology and public health and must be reduced. Phytoremediation treats heavy metal pollution in different ways. Over time, phytoremediation systems have developed unique ways that improve efficiency. Despite difficulties like site-specificity, sluggish remediation, and biomass buildup potential, phytoremediation is still a vital tool for environmental sustainability. 展开更多
关键词 PHYTOREMEDIATION HEAVY-METAL CONTAMINATION SUSTAINABILITY RESTORATION
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A Review of Cybersecurity Challenges in Small Business: The Imperative for a Future Governance Framework
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作者 Binita Saha Zahid Anwar 《Journal of Information Security》 2024年第1期24-39,共16页
Technological shifts—coupled with infrastructure, techniques, and applications for big data—have created many new opportunities, business models, and industry expansion that benefit entrepreneurs. At the same time, ... Technological shifts—coupled with infrastructure, techniques, and applications for big data—have created many new opportunities, business models, and industry expansion that benefit entrepreneurs. At the same time, however, entrepreneurs are often unprepared for cybersecurity needs—and the policymakers, industry, and nonprofit groups that support them also face technological and knowledge constraints in keeping up with their needs. To improve the ability of entrepreneurship research to understand, identify, and ultimately help address cybersecurity challenges, we conduct a literature review on the state of cybersecurity. The research highlights the necessity for additional investigation to aid small businesses in securing their confidential data and client information from cyber threats, thereby preventing the potential shutdown of the business. 展开更多
关键词 ENTREPRENEURSHIP CYBERSECURITY Small and Medium Businesses Data Breach HACKING Security
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Soil carbon pools of six ecological regions of the United States 被引量:2
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作者 Amitava Chatterjee 《Journal of Forestry Research》 SCIE CAS CSCD 2020年第5期1933-1938,共6页
Mineralisable soil organic carbon(SOC)pools vary with ecosystem type in response to changes in climate,vegetation and soil properties.Understanding the effect of climate and soil factors on SOC pools is critical for p... Mineralisable soil organic carbon(SOC)pools vary with ecosystem type in response to changes in climate,vegetation and soil properties.Understanding the effect of climate and soil factors on SOC pools is critical for predicting change over time.Surface soil samples from six ecoregions of the United States were analyzed for permanganate oxidizable C(KMnO4-C)and mineralizable C pools.Variations of SOC ranged from 7.9 mg g^-1(Florida site)to 325 mg g^-1(Hawaii site).Mineralisable C pools and KMnO4-C were highest in soils from the Hawaii site.Mean annual precipitation explains SOC and resistant C pool variations.Clay content was related to mineralisable active C pools and bacterial abundance.Mean annual precipitation and clay content are potential variables for predicting changes in SOC pools at large spatial scales. 展开更多
关键词 Permanganate oxidizable carbon(KMnO4-C) Resistant carbon pool Mean residence time Soil carbon pools United States
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Alternative Weed Control Methods during Grape Establishment in the United States Upper Midwest 被引量:1
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作者 John Stenger Harlene Hatterman-Valenti 《Agricultural Sciences》 2016年第6期357-363,共7页
A field experiment was conducted to determine the effects of three mulches (straw, landscape fabric, and woodchip) and a single spring herbicide application (combination of oryzalin, flumioxazin, and glyphosate) on an... A field experiment was conducted to determine the effects of three mulches (straw, landscape fabric, and woodchip) and a single spring herbicide application (combination of oryzalin, flumioxazin, and glyphosate) on annual weed control and grapevine establishment in North Dakota. Vine growth, bud-break timing, bud hardiness and soil conditions were monitored to determine weed control method effects on vine progress. More consistent yellow foxtail (Setaria glauca L.) control occurred in mulched plots compared to plots treated with herbicide, particularly late in the season. In 2009, vines in mulched plots’ bud-break date were up to five days later when compared to vines grown in herbicide treated plots. However, no differences were observed in the spring of 2010. Overall, differences in growth rate were due to cultivar differences and not weed control methods. Results suggest that any of the three mulches could be used for annual weed control in northern vineyards during establishment as they offered at least as much weed control as the herbicide control and did not adversely affect vine establishment. However, continued research is needed to determine if mulches will alter fruit yield and quality upon vine maturation and together influence winter dieback of vines. 展开更多
关键词 VITIS Hybrid Floor Management HERBICIDE MULCH
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Temperature Sensitivity of Nitrogen Dynamics of Agricultural Soils of the United States 被引量:1
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作者 Amitava Chatterjee Alexsandro Felipe de Jesus +6 位作者 Diksha Goyal Sailesh Sigdel Larry J. Cihacek Bhupinder S. Farmaha Sindhu Jagadamma Lakesh Sharma Daniel S. Long 《Open Journal of Soil Science》 2020年第7期298-305,共8页
Soil temperature controls gaseous nitrogen losses through nitrous oxide (N<sub>2</sub>O) and ammonia (NH<sub>3</sub>) fluxes. Eight surface soils from agricultural fields across the United Stat... Soil temperature controls gaseous nitrogen losses through nitrous oxide (N<sub>2</sub>O) and ammonia (NH<sub>3</sub>) fluxes. Eight surface soils from agricultural fields across the United States were incubated at 10<span style="white-space:nowrap;">°</span>C, 20<span style="white-space:nowrap;">°</span>C, and 30<span style="white-space:nowrap;">°</span>C, and N<sub>2</sub>O and NH<sub>3</sub> flux were measured twice a week for 91 and 47 d, respectively. Changes in cumulative N<sub>2</sub>O and NH<sub>3</sub> flux and net N mineralization at three temperatures were fitted to calculate Q<sub>10</sub> using the Arrhenius equation. For the majority of soils, Q<sub>10</sub> values for the N<sub>2</sub>O loss ranged between 0.23 and 2.14, except for Blackville, North Carolina (11.4) and Jackson, Tennessee (10.1). For NH<sub>3</sub> flux, Q<sub>10</sub> values ranged from 0.63 (Frenchville, Maine) to 1.24 (North Bend, Nebraska). Net soil N mineralization-Q<sub>10</sub> ranged from 0.96 to 1.00. Distribution of soil organic carbon and total soil N can explain the variability of Q<sub>10</sub> for N<sub>2</sub>O loss. Understanding the Q<sub>10</sub> variability of soil N dynamics will help us to predict the N loss. 展开更多
关键词 Arrhenius Equation Soil Organic Carbon Inorganic Nitrogen Gaseous Losses of Nitrogen
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How United States Agricultural Herbicides Became Military and Environmental Chemical Weapons: Historical and Residual Effects 被引量:1
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作者 Kenneth R. Olson Larry Cihacek 《Open Journal of Soil Science》 2022年第2期13-81,共69页
Discoveries in Charles Darwin’s laboratory led to modern herbicides. Darwin discovered the internal mechanism that directed plants to grow toward sunlight and sources of water. Scientists in Europe and America later ... Discoveries in Charles Darwin’s laboratory led to modern herbicides. Darwin discovered the internal mechanism that directed plants to grow toward sunlight and sources of water. Scientists in Europe and America later called this mechanism a plant’s hormone response system. Administrators and scientists, including Dr. Ezra J. Kraus, the Head of the Botany Department at the University of Chicago and a plant physiologist, suggested on the eve of WWII that weed killers had significant military value as chemical weapons. Dr. Kraus obtained access to a synthetic chemical, 2,4-D, and found that when the chemical was absorbed through the leaves of plants, it destroyed a plant’s hormones. After exposure, the plant experienced rapid and uncontrolled growth, and then the leaves shriveled, died and fell off. Dr. Kraus obtained funding for his Department of Botany research program from Department of Defense (DOD) during World War II (WWII). Camp Detrick (Biological Weapons Laboratory) scientists later obtained samples of newly created 2,4,5-T which contained unknown amounts of the by-product dioxin TCDD. In the 1950s and 1960s, Fort Detrick military scientists formulated the herbicide Agent Orange, which was a 50 - 50 mixture of 2,4-D and 2,4,5-T. These dual purpose herbicides were used by DOD and USDA. American and European farmers in the 1940s used 2,4-D and 2,4,5-T to eliminate weeds from pastureland and cropland. After WWII, synthetic herbicides (and pesticides) development continued in tandem with production of synthetic fertilizers and breeding of high-yield plant varieties. These new agricultural products were then shipped worldwide to increase crop yields, as part of the Green Revolution. This new system of agricultural technologies was intended to eliminate global starvation and increase food security by increasing field and farm crop yields. In contrast, the goal of military use of herbicides, as chemical weapons, was to defoliate jungle forests and destroy food crops as a strategy to win battles and wars. The primary objective of this research study is to describe how agricultural herbicides became tactical chemical weapons. A current assessment will address the environmental impacts of military and environmental chemical weapons on the United States and Vietnam ecosystems and need for additional dioxin TCDD hotspot clean-up efforts. 展开更多
关键词 Agent Orange Agent Blue Dioxin TCDD Cacodylic Acid Arsenic Environmental Weapons Chemical Weapons Ecocide TIBA 2 4-D 2 4 5 -T Ezra J. Kraus Arthur W. Galston Green Revolution Agricultural Herbicides
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The Gondwana Orogeny in northern North Patagonian Massif:Evidences from the Caita Có granite, La Se?a and Pangaré mylonites,Argentina
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作者 Daniel A.Gregori Bernhardt Saini-Eidukat +3 位作者 Leonardo Benedini Leonardo Strazzere Mercedes Barros José Kostadinoff 《Geoscience Frontiers》 SCIE CAS CSCD 2016年第4期621-638,共18页
Structural analyses in the northern part of the North Patagonia Massif, in the foliated Caita Co granite and in La Sefia and Pangare mylonites, indicate that the pluton was intruded as a sheet-like body into an openin... Structural analyses in the northern part of the North Patagonia Massif, in the foliated Caita Co granite and in La Sefia and Pangare mylonites, indicate that the pluton was intruded as a sheet-like body into an opening pull-apart structure during the Gondwana Orogeny. Geochronological studies in the massif indicate a first, lower to middle Permian stage of regional deformation, related to movements during indentation tectonics, with emplacement of foliated granites in the western and central areas of the North Patagonian Massif. Between the upper Permian and lower Triassic, evidence indicates emplacement of undeformed granitic bodies in the central part of the North Patagonian Massif. A second pulse of deformation between the middle and upper Triassic is related to the emplacement of the Caita CO granite, the development of mylonitic belts, and the opening of the Los Menucos Basin. During this pulse of deformation, compression direction was from the eastern quadrant. 展开更多
关键词 Gondwana Orogeny Northern Patagonia Foliated granite MYLONITES ARGENTINA
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Spring Wheat Response to Disease Control and Subsurface Drainage Management in the Red River of the North Valley, USA
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作者 Grant H. Mehring Hans J. Kandel +2 位作者 Joel K. Ransom Amanda Schoch Dean D. Steele 《Agricultural Sciences》 2015年第10期1220-1231,共12页
Increased variability in rainfall events and high production input costs are driving agricultural producers to consider subsurface water management in the flat Red River of the North Valley in Eastern North Dakota and... Increased variability in rainfall events and high production input costs are driving agricultural producers to consider subsurface water management in the flat Red River of the North Valley in Eastern North Dakota and Northwestern Minnesota, USA. Subsurface tile incorporated with water table control structures was utilized from 2009 to 2011 to investigate the response of hard red spring wheat (HRSW) (Triticum aestivum L. emend. Thell.) for yield, disease, and other agronomic characteristics to soil water management. A factorial arrangement of four cultivars, two seed treatments, and two foliar fungicide treatments in a split-plot design with closed and open tile as whole-plots was used. Mean wheat yields averaged across years were not significantly different with closed or open tile treatments. There existed an optimum management practice where plant useable water was not freely drained and analyzing the data with the optimum water management for each year found the optimum water table managed treatment yielded higher with 3812 kg ha-1 compared with limited water table management with 3679 kg ha-1. In 2011, the cultivars Faller and Howard were taller, and Traverse had lower root disease severity. In 2010 and 2011, Howard and Traverse had more leaf disease with open tile compared with closed tile. Across years, there was no difference in root disease, stand, number of spikes, crop height, or yield response to appli-cation of seed treatments with open or closed tile. In 2010, there was a 3.7% yield advantage with application of seed treatment on open tile. Across years, there was no yield response to application of foliar fungicides;however, wheat yield with foliar fungicide was 5% higher than without application in 2010. Producers should be using water table control and disease management to maximize HRSW yield. Further research should investigate water table management throughout the season based on weather conditions. 展开更多
关键词 SPRING WHEAT DISEASE Control SUBSURFACE Drainage Water TABLE
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Soybean Nodulation and Plant Response to Nitrogen and Sulfur Fertilization in the Northern US
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作者 Benjamin D. Cigelske Hans Kandel Thomas M. DeSutter 《Agricultural Sciences》 2020年第6期592-607,共16页
Soybean [<em>Glycine max</em> (L.) Merrill] seed yields in the northern United States may increase with the application of fertilizers;however Nitrogen (N) may decrease root nodulation. This study was cond... Soybean [<em>Glycine max</em> (L.) Merrill] seed yields in the northern United States may increase with the application of fertilizers;however Nitrogen (N) may decrease root nodulation. This study was conducted to understand the impact of N and sulfur (S) fertilization on soybean nodulation, plant, shoot and root biomass. Two cultivars were planted in experiments across ten site-years during 2015-2016. Plant observations took place at the V4 and R4 soybean growth stages. There were 41% more nodules per plant at R4 compared to V4 (38.3 vs 27.2 nodules, respectively). Cultivars responded differently to N and S fertilizer. The nodules per plant between the cultivars (30.3 vs 24.4) were different as well as the percent medium and large-sized nodules, which indicates the need to evaluate additional genotypes. Adding N decreased root nodulation (from 31.8 to 23.7 nodules per plant) and decreased nodule size but had no effect on plant, shoot or root mass. Averaged across N rates total plant mass was 2.26 and 11.36 g per plant at V4 and R4, respectively. Shoot mass, average across N rates was 1.77 and 9.65 g per plant at V4 and R4, respectively, and root mass, average across N rates was 0.49 and 1.71 g per plant at V4 and R4, respectively. Sulfur did not have an effect on nodules per plant but increased the percent medium size nodules at the R4 observation. There was no N by S interaction observed for nodule number, size of the nodules, and plant, root and shoot mass. As cultivars differed in their nodulation response to N and S, additional research would be helpful to screen other cultivars. 展开更多
关键词 SOYBEAN NITROGEN SULFUR NODULATION Shoot Mass Root Mass
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Effect of Weather on Grain Quality Traits of Durum Wheat Grown in the Northern Plains of USA
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作者 Sara Moayedi Elias M. Elias Frank A. Manthey 《American Journal of Plant Sciences》 2021年第12期1894-1911,共18页
The objective of this research was to determine <span style="font-family:;" "="">the effect of genotype and growing environment, particularly weather, on grain quality traits of durum wh... The objective of this research was to determine <span style="font-family:;" "="">the effect of genotype and growing environment, particularly weather, on grain quality traits of durum wheat using nine genotypes (Alkabo, Carpio, Divide, Grenora, Joppa, Maier, Mountrail, Pierce, and Tioga) grown in four years (2012-2015) at six locations in North Dakota, USA. The results of this research indicated that grain test weight, 1000-kernel weight, protein content, kernel vitreousness, and falling number were affected more by environment than by genotype. However, genotypes within an environment differed in the magnitude of their response and this difference could be used to select genotypes in a breeding program to improve quality. For a given quality trait, the magnitude of the response reflects the stability of the trait to changes in the environment. In general, the quality of durum wheat grown in the northern plains of USA was favored by warm daytime temperature, low night temperature, and low relative humidity. Growing locations with high maximum air temperature and a high number of days with temperature ≥ 30°C had a positive effect on grain protein content and falling number, while a high number of days with night time temperature ≤ 13°C were ideal for 1000-kernel weight. Low rainfall and low relative humidity promoted a high falling number and vitreous kernel content. The results of this study suggested that genotypes could be selected based on their overall quality and their stability across environments. Trait stability could be an important consideration when growers select genotypes for planting in their fields.</span> 展开更多
关键词 Durum Wheat WEATHER Grain Quality
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Productivity Growth in the Transportation Industries in the United States: An Application of the DEA Malmquist Productivity Index
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作者 Jaesung Choi David C. Roberts EunSu Lee 《American Journal of Operations Research》 2015年第1期1-20,共20页
This study reviews productivity growth in the five major transportation industries in the United States (airline, truck, rail, pipeline, and water) and the pooled transportation industry from 2004 to 2011. We measure ... This study reviews productivity growth in the five major transportation industries in the United States (airline, truck, rail, pipeline, and water) and the pooled transportation industry from 2004 to 2011. We measure the average productivity for these eight years by state in each transportation industry and the annual average productivity by transportation industry. The major findings are that the U.S. transportation industry shows strong and positive productivity growth except that in the years of the global financial crisis in 2007, 2008, and 2010, and among the five transportation industries, the rail and water sectors show the highest productivity growth in 2011. 展开更多
关键词 DEA MALMQUIST PRODUCTIVITY Index PRODUCTIVITY Growth U.S. TRANSPORTATION Industry
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