Nitrate in aquifers beneath agricultural systems

2002 ◽  
Vol 45 (9) ◽  
pp. 19-29 ◽  
Author(s):  
M.R. Burkart ◽  
J.D. Stoner

Research from several regions of the world provides spatially anecdotal evidence to hypothesize which hydrologic and agricultural factors contribute to groundwater vulnerability to nitrate contamination. Analysis of nationally consistent measurements from the U.S. Geological Survey’s NAWQA program confirms these hypotheses for a substantial range of agricultural systems. Shallow unconfined aquifers are most susceptible to nitrate contamination associated with agricultural systems. Alluvial and other unconsolidated aquifers are the most vulnerable and shallow carbonate aquifers provide a substantial but smaller contamination risk. Where any of these aquifers are overlain by permeable soils the risk of contamination is larger. Irrigated systems can compound this vulnerability by increasing leaching facilitated by additional recharge and additional nutrient applications. The agricultural system of corn, soybeans, and hogs produced significantly larger concentrations of groundwater nitrate than all other agricultural systems, although mean nitrate concentrations in counties with dairy, poultry, cattle and grains, and horticulture systems were similar. If trends in the relation between increased fertilizer use and groundwater nitrate in the United States are repeated in other regions of the world, Asia may experience increasing problems because of recent increases in fertilizer use. Groundwater monitoring in Western and Eastern Europe as well as Russia over the next decade may provide data to determine if the trend in increased nitrate contamination can be reversed. If the concentrated livestock trend in the United States is global, it may be accompanied by increasing nitrogen contamination in groundwater. Concentrated livestock provide both point sources in the confinement area and intense non-point sources as fields close to facilities are used for manure disposal. Regions where irrigated cropland is expanding, such as in Asia, may experience the greatest impact of this practice.

2007 ◽  
Vol 56 (1) ◽  
pp. 59-69 ◽  
Author(s):  
M.R. Burkart ◽  
J.D. Stoner

Research from several regions of the world provides spatially anecdotal evidence to hypothesize which hydrologic and agricultural factors contribute to groundwater vulnerability to nitrate contamination. Analysis of nationally consistent measurements from the U.S. Geological Survey's NAWQA program confirms these hypotheses for a substantial range of agricultural systems. Shallow unconfined aquifers are most susceptible to nitrate contamination associated with agricultural systems. Alluvial and other unconsolidated aquifers are the most vulnerable and also shallow carbonate aquifers that provide a substantial but smaller contamination risk. Where any of these aquifers are overlain by permeable soils the risk of contamination is larger. Irrigated systems can compound this vulnerability by increasing leaching facilitated by additional recharge and additional nutrient applications. The system of corn, soybean, and hogs produced significantly larger concentrations of groundwater nitrate than all other agricultural systems because this system imports the largest amount of N-fertilizer per unit production area. Mean nitrate under dairy, poultry, horticulture, and cattle and grains systems were similar. If trends in the relation between increased fertilizer use and groundwater nitrate in the United States are repeated in other regions of the world, Asia may experience increasing problems because of recent increases in fertilizer use. Groundwater monitoring in Western and Eastern Europe as well as Russia over the next decade may provide data to determine if the trend in increased nitrate contamination can be reversed. If the concentrated livestock trend in the United States is global, it may be accompanied by increasing nitrogen contamination in groundwater. Concentrated livestock provide both point sources in the confinement area and intense non-point sources as fields close to facilities are used for manure disposal. Regions where irrigated cropland is expanding, such as in Asia, may experience the greatest impact of this practice on groundwater nitrate.


2011 ◽  
Vol 23 (4) ◽  
pp. 186-191 ◽  
Author(s):  
Malini Ratnasingam ◽  
Lee Ellis

Background. Nearly all of the research on sex differences in mass media utilization has been based on samples from the United States and a few other Western countries. Aim. The present study examines sex differences in mass media utilization in four Asian countries (Japan, Malaysia, South Korea, and Singapore). Methods. College students self-reported the frequency with which they accessed the following five mass media outlets: television dramas, televised news and documentaries, music, newspapers and magazines, and the Internet. Results. Two significant sex differences were found when participants from the four countries were considered as a whole: Women watched television dramas more than did men; and in Japan, female students listened to music more than did their male counterparts. Limitations. A wider array of mass media outlets could have been explored. Conclusions. Findings were largely consistent with results from studies conducted elsewhere in the world, particularly regarding sex differences in television drama viewing. A neurohormonal evolutionary explanation is offered for the basic findings.


2020 ◽  
Vol 2 (4) ◽  
pp. 32-54
Author(s):  
Silvia Spitta

Sandra Ramos (b. 1969) is one of the few artists to reflect critically on both sides of the Cuban di-lemma, fully embodying the etymological origins of the word in ancient Greek: di-, meaning twice, and lemma, denoting a form of argument involving a choice between equally unfavorable alternatives. Throughout her works she shines a light on the dilemmas faced by Cubans whether in Cuba or the United States, underlining the bad personal and political choices people face in both countries. During the hard 1990s, while still in Havana, the artist focused on the traumatic one-way journey into exile by thousands, as well as the experience of profound abandonment experienced by those who were left behind on the island. Today she lives in Miami and operates a studio there as well as one in Havana. Her initial disorientation in the USA has morphed into an acerbic representation and critique of the current administration and a deep concern with the environmental collapse we face. A buffoonlike Trumpito has joined el Bobo de Abela and Liborio in her gallery of comic characters derived from the rich Cuban graphic arts tradition where she was formed. While Cuba is now represented as a rotten cake with menacing flies hovering over it ready to pounce, a bombastic Trumpito marches across the world stage, trampling everything underfoot, a dollar sign for a face.


Author(s):  
Jakub J. Grygiel ◽  
A. Wess Mitchell ◽  
Jakub J. Grygiel ◽  
A. Wess Mitchell

From the Baltic to the South China Sea, newly assertive authoritarian states sense an opportunity to resurrect old empires or build new ones at America's expense. Hoping that U.S. decline is real, nations such as Russia, Iran, and China are testing Washington's resolve by targeting vulnerable allies at the frontiers of American power. This book explains why the United States needs a new grand strategy that uses strong frontier alliance networks to raise the costs of military aggression in the new century. The book describes the aggressive methods which rival nations are using to test American power in strategically critical regions throughout the world. It shows how rising and revisionist powers are putting pressure on our frontier allies—countries like Poland, Israel, and Taiwan—to gauge our leaders' commitment to upholding the American-led global order. To cope with these dangerous dynamics, nervous U.S. allies are diversifying their national-security “menu cards” by beefing up their militaries or even aligning with their aggressors. The book reveals how numerous would-be great powers use an arsenal of asymmetric techniques to probe and sift American strength across several regions simultaneously, and how rivals and allies alike are learning from America's management of increasingly interlinked global crises to hone effective strategies of their own. The book demonstrates why the United States must strengthen the international order that has provided greater benefits to the world than any in history.


2008 ◽  
Vol 12 (1) ◽  
Author(s):  
Anthony G Picciano ◽  
Robert V. Steiner

Every child has a right to an education. In the United States, the issue is not necessarily about access to a school but access to a quality education. With strict compulsory education laws, more than 50 million students enrolled in primary and secondary schools, and billions of dollars spent annually on public and private education, American children surely have access to buildings and classrooms. However, because of a complex and competitive system of shared policymaking among national, state, and local governments, not all schools are created equal nor are equal education opportunities available for the poor, minorities, and underprivileged. One manifestation of this inequity is the lack of qualified teachers in many urban and rural schools to teach certain subjects such as science, mathematics, and technology. The purpose of this article is to describe a partnership model between two major institutions (The American Museum of Natural History and The City University of New York) and the program designed to improve the way teachers are trained and children are taught and introduced to the world of science. These two institutions have partnered on various projects over the years to expand educational opportunity especially in the teaching of science. One of the more successful projects is Seminars on Science (SoS), an online teacher education and professional development program, that connects teachers across the United States and around the world to cutting-edge research and provides them with powerful classroom resources. This article provides the institutional perspectives, the challenges and the strategies that fostered this partnership.


2015 ◽  
Vol 4 (1) ◽  
Author(s):  
Siluvai Raja

Education has been considered as an indispensable asset of every individual, community and nation today. Indias higher education system is the third largest in the world, after China and the United States (World Bank). Tamil Nadu occupies the first place in terms of possession of higher educational institutions in the private sector in the country with over 46 percent(27) universities, 94 percent(464) professional colleges and 65 percent(383) arts and science colleges(2011). Studies to understand the profile of the entrepreneurs providing higher education either in India or Tamil Nadu were hardly available. This paper attempts to map the demographic profile of the entrepreneurs providing higher education in Arts and Science colleges in Tamil Nadu through an empirical analysis, carried out among 25 entrepreneurs spread across the state. This paper presents a summary of major inferences of the analysis.


1997 ◽  
Vol 24 (1) ◽  
pp. 117-141 ◽  
Author(s):  
T. A. LEE

This study represents part of a long-term research program to investigate the influence of U.K. accountants on the development of professional accountancy in other parts of the world. It examines the impact of a small group of Scottish chartered accountants who emigrated to the U.S. in the late 1800s and early 1900s. Set against a general theory of emigration, the study's main results reveal the significant involvement of this group in the founding and development of U.S. accountancy. The influence is predominantly with respect to public accountancy and its main institutional organizations. Several of the individuals achieved considerable eminence in U.S. public accountancy.


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