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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Growth and function of four chalk grassland herbs in elevated CO←2

Ferris, Rachel January 1994 (has links)
No description available.
22

Vegetable Production Concentration in Northwest Mexico

Danel, Desiree Michelle 01 June 2014 (has links)
An American company that supplies premium quality hybrid vegetable seed to commercial growers in the southern part of the US, Mexico, and Central America sought an assessment of the market potential in the Northwest region of Mexico by identifying land area and production concentrations of vegetables by location, crop, and cultivation method, whether open-field, greenhouse, or shade house. Data on the cultivated area of four states in the Northwest region of Mexico was collected for 12 crops of interest for the period of 2003-2012 from secondary sources. Data was entered into a statistical software program to complete frequency distribution charts of each state by crop and cultivation method to determine crop concentrations. Trend data of cultivated area was also analyzed to see changes in cultivation methods over a 10 year period and estimates were made by for NW Mexico through 2017. An analysis of vegetable production in Northwest region of Mexico showed open-field cultivated area was heavily location specific with near monocultures present, especially in the state of Sinaloa. Two-thirds of the crops had a substantial portion of their cultivated area (35-80%) occurring in one place, with bell pepper, onion (green), spinach, and cucumber having a dominant percentage (80-100%) of their cultivation occurring only in Sinaloa. Although it made up a small percentage of overall cultivated area, the majority of protected culture cultivation was also located in Sinaloa, and was shown to have grown rapidly since being introduced or first appearing in government data sources in 2003. With open-field cultivation giving way to more technologically advanced cultivated methods of protected culture, and with the majority of protected culture and open-field export farming taking place in Sinaloa, further input suppliers’ marketing efforts should be concentrated there.
23

A market assessment of greenhouse products and associated rural development in semi-arid regions of Mexico

Quevedo-Martinez, Edgar Arturo. January 2009 (has links)
Thesis (M.S.)--West Virginia University, 2009. / Title from document title page. Document formatted into pages; contains xi, 103 p. : ill. (some col.), col. map. Includes abstract. Includes bibliographical references (p. 68-69).
24

Understanding the greenhouse effect using a computer model /

Schultz, Lisa. January 2009 (has links)
Thesis (M.S.) in Teaching--University of Maine, 2009. / Includes vita. Includes bibliographical references (leaves 83-86).
25

Potential contribution of a carbon offset scheme to the costs of greenhouse gas emissions reductions in developing countries

Partridge, Ian Alexander 22 February 2013 (has links)
The energy sector in the developing world is expected to account for 27% of global emissions of greenhouse gases from fossil fuel combustion in 2035 – in 1990 it accounted for 7%. The increase is concentrated in rapidly growing countries in Asia that depend on coal for power generation. Maximizing electricity generation using renewable technologies in these countries provides an obvious approach to slowing global emissions growth. A barrier to increased use of renewable generation is cost: financial incentives could help to increase its use in developing countries. The principal objective of this research is to examine the practicability and potential scale of an offset scheme aimed at providing this incentive. Offset schemes have a poor reputation due to problems experienced with the Clean Development Mechanism (CDM). I identify the CDM’s failure to ensure the additionality of projects as a key issue and propose an approach to the assessment of additionality specific to grid connected generation projects. I present case studies of wind and small hydro projects in China and India in which I calculate the marginal abatement cost of emissions cuts and use the new approach to additionality to draw conclusions regarding the eligibility of projects to receive offsets in some hypothetical future scheme. My analysis shows that the proposed approach offers advantages over methodologies permitted by the CDM. I analyze the supply and demand for credits from existing schemes during 2013-2020 and show that oversupply will continue to impact their price, removing any incentive for investment in renewable generation. Using an original approach based on IEA forecasts for the energy sector, I estimate the maximum availability of offsets from a post-2020 scheme based on renewable generation, and assess the potential global demand. / text
26

EFFECT OF NITROGEN FERTILIZER ON NITROUS OXIDE EMISSIONS FROM THE SOIL FOR TWO POTENTIAL ENERGY CROPS AND THE RELATIVE GREENHOUSE GAS EMISSIONS

Wile, Adam 10 August 2010 (has links)
The benefits from energy crops are debated. This two-year study was designed to investigate nitrous oxide (N2O) emissions, yield and ash content from fertilized bioenergy crops switchgrass and reed canary grass with and without inter-seeded red clover. Overall, N2O emissions were less than 1kg N2O-N ha-1 in the first year and around 100g N2O-N ha-1 in the second year with a N fertilizer effect in the first year. Plots inter-seeded with red clover received half the N fertilizer of pure grass stands but showed no difference in N2O emissions compared to the pure stands and also had higher ash content. Cumulative soil mineral N responded to N fertilizer addition but no effect of crop type was evident in 2008 and 2009. Yields for both crops were unresponsive to N fertilizer addition while pure switchgrass yielded higher than inter-seeded switchgrass in 2008 and switchgrass had lower ash content.
27

Climate change and future water resources in Wales

Holt, Christopher Paul January 1993 (has links)
No description available.
28

High tunnel production of tomatoes and snapdragons for season extension in southeastern Alabama

Reeder, Bredley Edwin, January 2006 (has links) (PDF)
Thesis(M.S.)--Auburn University, 2006. / Abstract. Vita. Includes bibliographic references.
29

Policy and innovation in low-carbon energy technologies

Nemet, Gregory Frank. January 1900 (has links)
Thesis (Ph.D.)--University of California, Berkeley, 2007. / Adviser: Daniel Kammen. Includes bibliographical references.
30

Influencia de tres tipos de sustrato en las características físicas, químcas y organolépticas a dos variedades de tomate riñon cultivadas en hidroponía bajo el sistema del panqar huyu

Yépez Vallejo, Carlos Fernando. January 2003 (has links)
Thesis (Ing.)--Universidad Técnica del Norte, Facultad de Ingeniería en Ciencias Agropecuarias y Ambientales, Escuela de Ingeniería Agroindustrial, 2003. / Reproduced from copy at BYU's Benson Institute. Includes bibliographical references (leaves 84-86).

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