Salinity intrusion, caused by global sea-level rise, is a major threat to paddy cultivation in the Mekong Delta of Vietnam (MKD). Salinity exposure reduces crop yields, increases soil salinity, and exacerbates fresh water scarcity, resulting in altered land use decisions and decreased paddy farming profitability. This study evaluates the effects of salinity intrusion on paddy yields and planted acreage, using a 21-year district-level panel dataset from the 13 provinces in the MKD. Specifically, we analyze the relationship between current salinity levels and paddy yield, as well as the relationship between lagged salinity levels and the paddy planted area. We examine these relationships across all districts, as well as for salinity-prone and non-salinity-prone districts and by proximity to the coast (20 km, 20-60 km, and 60+ km). The results indicate that salinity intrusion poses a significant challenge to paddy production in salinity-prone and coastal regions. Salinity level significantly and adversely affects paddy yields in salinity-prone and coastal districts. Similarly, high salinity levels in the past five years significantly reduce planted paddy acreage in these same regions. We also find that paddy yields in the MKD peaked in 2015 and have been declining since. The study highlights the regional differences in challenges associated with salinity intrusion in paddy production. Policymakers and agricultural managers need to take a region-specific approach to ensure that interventions are tailored to the specific needs and challenges faced by farmers. This entails supporting intensified paddy production in less salinity-prone areas and facilitating transitions to economically profitable alternatives to paddy in more salinity-prone areas. / Master of Science / Salinity intrusion, resulting from rising sea levels worldwide, poses a significant threat to paddy cultivation in the Lower Mekong Delta, Vietnam (MKD). The increased exposure to salinity adversely affects crop yields, exacerbates soil salinity levels, and contributes to freshwater scarcity. Consequently, this study aims to assess the effects of salinity intrusion on paddy yields and planted acreage in the MKD. By using a 21-year dataset covering thirteen provinces within the MKD, this study examines the relationship between current salinity levels and paddy yield, as well as the association between lagged salinity levels and the planted area of paddy crops. The analysis considers all districts within the region, distinguishing between salinity-prone and non-salinity-prone districts, as well as the proximity to the coast (20 km, 20-60 km, and 60+ km). The findings indicate that salinity intrusion presents a significant challenge to paddy production in both salinity-prone and coastal regions. High salinity levels substantially and adversely affect paddy yields in these districts. Furthermore, elevated salinity levels within the past five years significantly reduce the planted acreage of paddy crops in the same regions. Notably, paddy yields in the MKD reached their peak in 2015 and have been declining since. This study highlights the need for tailored strategies to address the diverse challenges faced by farmers in different regions. Policymakers and agricultural managers must support intensified rice production in areas that are less prone to salinity, while also promoting alternative crops in regions more vulnerable to salinity. By doing so, we can help sustain agricultural productivity and livelihoods in Vietnam's Mekong Delta, even in the face of salinity intrusion.

In rural areas of the eastern United States, which adhere to the metes and bounds system of land division, descriptions of land not based on surveys are commonly found in deeds of conveyance. A common element of these descriptions in which boundaries are not defined by bearings and distances is an estimation of acreage at the terminus of the description. The objectives of this research are to investigate the accuracy of acreage estimated in descriptions not based on surveys and determine if characteristics of the land described are significant in explaining the variability of the accuracy measures obtained. These objectives are accomplished by: (1) establishment of accuracy of measuring parcel size from aerial photography; (2) comparison of acreage estimate in descriptions with measured parcel size; (3) the over-assessment of variables, such as parcel size, in conjunction with the comparison of deeded acreage to mapped parcel acreage. This study is based on data obtained from public records in Morgan County, Kentucky, a rural eastern Kentucky county. A sample of 204 parcels was examined. The results indicate that parcel acreage estimated in deeds averages 12.9 percent more than acreage measured from aerial photographs. Parcel size was the only significant variable explaining variation in the comparison of described acreage to mapped parcel acreage. Background information, methods of investigation, and results and conclusions are included. / M.S.

Master of Science / Department of Agricultural Economics / Andrew Barkley / This research identifies and quantifies the impact of biophysical and economic variables on Kansas crop acreage and yields for the period 1977- 2007. Due to long production time requirements, agricultural producers must make vital decisions with imperfect information, based on expectations of future agronomic and economic conditions. This research analyzes the impact of price, climate, and yield expectations on crop acreage allocations and yield responses for the four major commodities produced in Kansas: corn, soybeans, wheat, and grain sorghum (milo). By modeling and analyzing both biophysical and economic variables, total supply response can be estimated for potential future changes in prices, yields, climate, and weather outcomes. The analysis of both biophysical and economic conditions allows for the estimation of supply response in the short and long run. The results provide updated, more precise results than previous research, which has often separated acreage and yield response.

Climate change and rapid urbanization have caused several vulnerabilities for the global food system, and alternative farming methods are required to solve this ongoing crisis. Zero acreage farming can be a sustainable farming a to geoponics, as it is developing worldwide, and in Stockholm, this provides an opportunity to produce food year-round. In addition to that, it makes the food system more resilient and increases food security. The thesis aimed to explore the possibilities of zero-acreage farming on household rooftops in Stockholm and achieve the demand for tomatoes with an aeroponics growing system. With the help of GIS software, 4269 flat and slant roofs with a total available area of 3815121 m2 are found to implement a greenhouse. The GIS study shows that the south sector had the better potential for more extensive operations considering buildings, more population, and broader roads where transportation will be made more accessible. The central sector had the least potential for zero acreage farming because those regions have heritage values and narrow streets, making the transportation and supply chain difficult. The result of the aeroponics growing system reveals that the Stockholm tomato demand can be achieved in a 12780 m2 area with 95% water saving and 90% less global warming potential (GWP)compared to geoponics or conventional farming. Further on, this thesis suggests aeroponics as a sustainable alternative way of growing crops to minimize the impact on the environment caused by geoponics over the centuries.

The objective of my master's thesis is comparison of selected methods of valuation of building land-type real estate in the locality of Třinec and its surroundings. My thesis is focused on properties, built up with houses on each of the lots , on which the construction of a house is planned. Both groups of these properties have been estimated by the methods and historical prices have been compared and analyzed.The integral part of the master's thesis is the evaluation of the individual methods of estimation,according to the pre-determined criteria.

The diploma thesis is focused on the analysis of the implementation and valuation of the BIM model in a construction company. In the practical part, a specific construction company and its project is selected for the implementation and valuation using valuation plugins, which define the elements according to the design classification. For the purposes of this work, the constructions of the main building production are selected - piles, prefabricated load-bearing skeleton, wall perimeter cladding and roof folded cladding. Based on the model developed in this way, the BIM model is compiled and by exporting data from valuation plugins, an item budget is processed. The main result of this work is to perform an implementation analysis and show the advantages and disadvantages of the BIM approach to projects.

This thesis covers two separate studies. The first study, chapter 2, was conducted to evaluate whether there are additional economic returns from producing strawberries in the high tunnel compared to the open-field in Southeast Virginia. We develop and compare budgets for eight strawberry cultivars grown in the two environments and sold under three marketing strategies (pre-pick wholesale, pre-pick retail, and U-pick). Almost all cultivars in the high tunnel generated negative net revenues regardless of the marketing strategy. In contrast, net revenues from open-field cultivars were always positive. In the second study, chapter 3, we used a fractional multinomial logit model to estimate the effect of crop revenues, input costs, and fuel ethanol production on the joint acreages planted to eight U.S major crops (barley, corn, cotton, peanuts, rice, sorghum, soybeans, and wheat). We found a positive and statistically significant marginal effect of the expected peanuts' revenue on its acreage share. The expected corn revenue had a negative average marginal effect on soybean acreage share, and the effect of expected wheat revenue was positive on cotton acreage share and negative on rice acreage share. / Master of Science / This thesis covers two separate research studies. The first study, chapter 2}, was conducted to evaluate whether growing strawberries in a simple, low-cost, and passive heat structure known as a "high tunnel" would yield more profit (the difference between total revenues and total costs) compared to growing them outside in an open-field in Southeast Virginia. We estimate and compare differences between total revenues and costs for eight strawberry cultivars grown in the two environments and sold under three marketing strategies. The first two marketing strategies involve growers harvesting strawberries themselves. They can then either retail them (farm stands, farmers' markets, or in a similar setting: pre-pick retail) or sell them in bulk to be retailed by others (pre-pick wholesale). A third marketing strategy involves consumers visiting a farm and picking their own strawberries (U-pick). Almost all cultivars grown in the high tunnel structure resulted in a loss (negative difference between total revenues and costs) regardless of the marketing strategy. In contrast, cultivars produced in the open-field always generated a profit (positive total revenues and costs difference). In the second study, chapter 3, we estimated the effect of crop revenues, input costs, and fuel ethanol production on acreages planted to eight U.S major crops (barley, corn, cotton, peanuts, rice, sorghum, soybeans, and wheat), and we considered the fact that acreages allocated to one crop affect other crops' acreages. We found that increasing the expected revenue of peanuts leads to an increase in its acreage share. Increasing the expected revenue of corn leads to a decrease in soybeans' acreage share. Finally, increasing the expected revenue of wheat leads to an increase in the cotton acreage share and a decrease in the rice acreage share.

From the Proceedings of the 1975 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - April 11-12, 1975, Tempe, Arizona / Pinal County is one of Arizona's largest farm and highest farm income areas. Agriculture there is completely dependent upon irrigation systems, with nearly all of the water supply pumped from underlying groundwater reservoirs. Delivery of central Arizona project water will not assure groundwater conservation at a one to one trade-off ratio. Most of the monetary benefits to agriculture derived from the project will be realized by Indian farmers. Cotton acreage will not be affected, but the acreage of small grains and alfalfa will increase. The increasing salinity of cap water should be of no concern to Pinal County farmers.

Dans cette thèse, nous nous intéressons aux questions de l’hétérogénéité inobservée et des solutions en coin dans les modèles de choix d’assolements. Pour répondre à ces questions, nous nous appuyons sur un modèle de choix de production multicultures avec choix d’assolement de forme NMNL, dont nous proposons des extensions. Ces extensions conduisent à des problèmes spécifiques d’estimation, auxquels nous apportons des solutions. La question de l’hétérogénéité inobservée est traitée en considérant une spécification à paramètres aléatoires. Ceci nous permet de tenir compte des effets de l’hétérogénéité inobservée sur l’ensemble des paramètres du modèle. Nous montrons que les versions stochastiques de l’algorithme EM sont particulièrement adaptées pour estimer ce type de modèle.Nos résultats d’estimation et de simulation montrent que les agriculteurs réagissent de façon hétérogène aux incitations économiques et que ne pas tenir compte de cette hétérogénéité peut conduire à des effets simulés de politiques publique biaisés.Pour tenir compte des solutions en coin dans les choix d’assolement, nous proposons une modélisation basée sur les modèles à changement de régime endogène avec coûts fixes associés aux régimes. Contrairement aux approches basées sur des systèmes de régression censurées, notre modèle est cohérent d’un point de vue micro-économique. Nos résultats montrent que les coûts fixes associés aux régimes jouent un rôle important dans le choix des agriculteurs de produire ou non certaines cultures et qu’ils constituent, à court terme, un déterminant important des c / In this thesis, we are interested in questions of unobserved heterogeneity and corner solutions in acreage choice models. To answer these questions, we rely on a NMNL acreage share multi-crop models, of which we propose extensions. These extensions lead to specific estimation problems, to which we provide solutions.The question of unobserved heterogeneity is dealt with by considering a random parameter specification. This allows us to take into account the effects of the unobserved heterogeneity on all the parameters of the model. We show that the stochastic versions of the EM algorithm are particularly suitable for estimating this type of modelOur estimation and simulation results show that farmers react heterogeneously to economic incentives and that ignoring this heterogeneity can lead to biased simulated effects of public policies.In order to take account of the corner solutions in acreage choices, we propose modelling based on endogenous regime switching models with regime fixed costs. Unlike approaches based on censored regression systems, our model is “fully” consistent from a micro-economic viewpoint. Our results show that the regime fixed costs play an important role in farmers’ choice to produce or not some crops and they are, in the short term, an important determinant of acreage choices.