Fifteen countries which are members of the Southern African Development Community (SADC) have embarked on a regional integration initiative. In 1996, a trade protocol that aimed to increase trade among members by removing trade barriers was signed. In the year 2000, this protocol was implemented, leading to a Free Trade Area (FTA) in 2008. More than 85 % of SADC trade was free of customs duties from 2008 onwards. However, while custom tariffs were reduced, the share of SADC trade did not show any improvement over the tenyear period after implementing the trade protocol. Accordingly, the objective of this study is to examine the factors which contributed to lack of improvement in SADC trade, particularly the role of Non-Tariff Measures (NTMs). One of the main challenges in analysing NTMs in SADC is the unavailability of relevant information. An SADC NTM database was built as a repository of official NTMs. In order to quantify NTMs, a database was classified, similarly to the international database. Agricultural products at HS 4-digit level for ten SADC countries were included in this repository, and groupedinto six main categories; namely animal products, cereals, horticultural products, oilseeds, industrial and processed products. The trade data challenges within SADC countries inadvertently prescribed the econometric methods to apply for the set objectives of the study. The two main challenges of SADC trade data are missing data for some years and high percentage of zero trade flows. A latent threshold gravity model was employed with hierarchical specification to control for country effects. The hierarchical model captures individual country effects, such as the impact of NTMs on trade volumes, and thus intra-SADC trade. Such impact was then assessed when an additional NTM is introduced or increases trade volumes. The two effect models were examining the attributes of changes in regional trade, as well as those attributes of change in NTMs. The effects NTMs were incorporated into the model by weighting the number of NTMs by share of trade in the region, as well as ranks of country NTMs within product groups. Types of NTMs which were estimated are Sanitary and Phyto-Sanitary measures (SPS), Technical Barriers to Trade (TBT) and an aggregation of all other NTMs which do not belong to the two groups. Results show that there is evidence NTMs were increasing at the same period when tariffs were being reduced. Using the inventory methods of evaluating presence and prevalence of NTMs, it was also evident that NTMs are used across most agricultural products. The percentage of products affected by NTMs in 2010 was much higher than in 2000. The econometric model results show that all gravity model variables, GDP, border and language were consistent with the theoretical expectations.Distance does nothave significant influence on SADC trade. The reason for this has to do with the trading pattern of SADC countries, which is very high between contiguous members, compared to non-contiguous members. The estimation of zero observed trade, using a threshold model, provided additional understanding of the role and reasons for such trade. The estimated effects of the observed zero trade showed that if this threshold is high, implying that trade costs (NTMs) are restricting trade, then zero trade was observed. When high percentage of zero trade is observed, then intra-SADC trade remains small or declines. However, if the threshold is low, intra-SADC trade increases, as was observed in the case of industrial products. The overall results confirm that NTMs do have an impact on intra-SADC trade. Industrial and cereal products are more responsive to NTMs than the other five product groups. A unit change in NTMs by regional trade members has more effects on intra- regional trade than a unit change in trade value. That is the case because the SADC is already exchanging a large share of its total trade with non-SADC members. Therefore, attention should be given to addressing the way NTMs are introduced. One of the important findings from the study is that the intra-SADC trade is affected more by the effect of an additional NTM, than an additional unit of trade in value. The effect of addressing NTMs is one and half more than those of additional trade value. So, in order to improve intra-SADC trade performance, focus must on addressing the NTMs and growing trade. In addressing NTMs, it does not necessarily require removing or even reducing them. It is about making it easy to comply with them. SADC trade can be improved substantially by aiming to harmonise NTMs and overall policies. / Thesis (PhD)--University of Pretoria, 2014. / lk2014 / Agricultural Economics, Extension and Rural Development / PhD / unrestricted

This dissertation consists of three chapters that estimate the elasticities regarding price and time in trade and household production. Chapters 1 and 2 estimate price elasticities. Chapter 1 estimates the one-factor-one-price elasticity of substitution (OOES)—or how the percentage change in the quantity of one good responds to the percentage change in the price (of itself or another good)—in an international trade context. Chapter 2 estimates the two-factor-one-price elasticity of substitution (TOES)—or the difference of percentage changes between two quantities with respect to the percentage change in the price of one good—in the context of household food production. Chapter 3 estimates the elasticity of export quantity and value with respect to delays in the time it takes to load or unload products at US ports. Chapter 1 estimates the price elasticities in agricultural trade. Armington elasticities, the elasticity of substitution between goods from different countries, are key parameters in agricultural trade policy evaluation and welfare calculation. We estimate Armington elasticities for a selected basket of 38 agricultural commodities in 5 categories by compiling a sample of 118 countries' production and trade flows. Following and extending Feenstra et al. (2018), we estimate both the micro-elasticity of substitution between foreign sources of imports and the macro-elasticity of substitution between home and imported products at the commodity level. The median of the micro- and macro-elasticities are 6.4 and 5.0, respectively. Meat products have the lowest micro- and macro-elasticities, with the micro-elasticities ranging from 4.2 (pork) to 5.0 (poultry) and the macro-elasticities ranging from 2.9 (pork) to 4.5 (beef). Crops products have the widest range of Armington elasticities, with micro-elasticities ranging from 2.5 (pigeon peas) to 90.3 (peanuts), and macro-elasticities ranging from 1.2 (pigeon peas) to 20.1 (peanuts). In line with the literature, we find that 75 percent of the agricultural commodities have numerically smaller macro-elasticities than micro-elasticities, even though only 6 of them (pork, poultry, corn, peanuts, apples, and peppers) are statistically smaller at the 5 percent level. We explore the robustness of our estimates by slicing the sample into separate periods and importing countries. Finally, we discuss the policy implications of our estimates on predicting trade due to tariff changes and understanding welfare gains from agricultural trade. Chapter 2 estimates the goods-time elasticity of substitution (EOS), the responsiveness of the difference between money and time in household production for change of opportunity cost of time (OCT). This chapter bridges the gap between literature that directly and indirectly estimates the goods-time EOS in household production. Inspired by the studies in environmental economics, we argue the opportunity cost of time in household production not only depends on wage but life-cycle dynamics and household demographics as well. We proceed with the estimation by two strategies: direct estimation of the household production, and the demand-supply approach borrowed from Feenstra's (1994) research on trade elasticities. Both strategies report the estimates are much larger than unit and closer to previous indirect estimates. We show our results are robust when applied to Aguiar and Hurst's (2007) sample, in which they employed the indirect estimation. The larger goods-time EOS indicates policies aiding households with money for groceries like the Supplemental Nutrition Assistance Program (SNAP) are more sufficient, since money for certain groceries can more easily substitute for time in making meals. Chapter 3 explores the elasticity of trade with respect to port congestion time. U.S. ports have struggled with significant supply chain congestion during the past two years. Anecdotal evidence shows the increasing port congestion brought substantial losses to U.S. exports, particularly agricultural shipments. However, previous studies are limited by the availability of explicit data on congestion times for unloading. This study first quantifies the association between port congestion days and U.S. agricultural exports, using monthly export data of top U.S. ports and their monthly average container and bulk shipments delays. We find one extra day delay of container shipments decreases U.S. agricultural monthly exports by 5 percent in quantity or 2 percent in value on average. That amounts to $63 million in monthly loss of export value on average, and Western U.S. ports are responsible for 69 percent of this total. The effect is most pronounced for the Western U.S. exports of bulk commodities, where congestion results in a 9 percent loss in quantity or 8 percent loss in value. For Eastern U.S., the most salient effect is on consumer commodities, with a loss of 3 percent in quantity and 3 percent in value. For the Gulf region, the largest effect is on bulk commodities, with a loss of 4 percent in quantity and 5 percent in value. The impacts of congestion on bulk shipments are both statistically and economically insignificant. However, we find some evidence that exporters substitute bulk cargoes with containers when bulk shipment delays at ports increase. The substitution of container shipments with bulk shipments, however, is unlikely. / Doctor of Philosophy / This dissertation explores price and time factors in trade and household production. All three chapters estimate the percentage change in a variable for the percentage change to some other variables (i.e., an elasticity). Chapter 1 estimates the elasticities in international agricultural trade. The core concept the first chapter relies on is the one-factor-one-price elasticity of substitution (OOES), or how the percentage change in the quantity of one good responds to the percentage change in the price (of itself or another good). Chapter 2 estimates the two-factor-one-price elasticity of substitution (TOES)—or the difference of percentage changes between two quantities with respect to the percentage change in the price of one good—in household food production context. The third chapter estimate the responsiveness of export quantity/value to time delays at port. The first chapter examines how the demand for agricultural product imports will respond to price change. The study quantifies the responsiveness at two levels—micro and macro—using the Armington model, in which the product from each country is considered as a "variety". The micro-level elasticities capture the import demand responsiveness for a country of variety, say, Australian beef, when beef import price from Australia changes; The macro-elasticities capture the import demand responsiveness when, say, beef import prices from all countries change. We estimate both elasticities for a basket of 38 commodities, to shed light on policies such as "trade war" and multilateral trade agreements. In the median, one percent increase in price from a country of variety decreases 6.4 percent of demand for it; one percent decrease of price from all countries increases import demand by 5.0 percent. The second chapter studies the substitutability between money and time in household production, or the goods-time elasticity of substitution (EOS), which captures the percentage change of money (for grocery purchases) relative to time (for food preparation and cleaning up, etc.) for the change of price of time. But what is the price of time in food production? Economists use the term opportunity cost of time (OCT), the highest value that household could spend their time on if not on food production. While most economists agree that OCT correlates with wage, this chapter argues the correlation differs by life cycle and household characteristics. What's more, OCT should also include non-wage factors like household characteristics. Maybe households with children in their middle age just value time with children more than the market wage. In this case, the value of time with children, instead of wage, could be their OCT in food production. Based on these arguments, the study estimates the goods-time EOS is much larger than in previous studies. The magnitude of goods-time EOS has strong policy implications for policies like the Supplemental Nutritional Assistance Program (SNAP), which provides lower-income households money to buy groceries. If money and time are more substitutable, SNAP benefits will be more sufficient since money for certain groceries can more easily substitute for time in making meals. If goods-time EOS is small, however, SNAP benefits will be less sufficient, since the groceries are hardly substitutable for time in food production, and households still need to input a significant amount of time. The third chapter considers the time factor in international trade. It leverages the bottleneck of the international supply chain, port delays, in past years to study the elasticity of trade with respect to port congestion time. The study focuses on U.S. agricultural exports of bulk shipments and container shipments. We estimate that each day of container shipment delay is associated with 5 percent decrease in export quantity and 2 percent decrease in export value. Compared with the estimates of micro-elasticities in Chapter 1, one-day delay of container shipment is equivalent to imposing extra 0.8 percent of tariff on U.S. agricultural products in the median. The effect of bulk shipment delay is muted. Chapter 3, combined with Chapter 1, sheds light on the price of time in agricultural trade.

This dissertation consists of three essays examining the impacts of Sanitary and Phytosanitary (SPS) Measures on agricultural trade. The first essay estimates the impact of the 2003 Bovine Spongiform Encephalopathy (BSE) outbreak in the US on Japanese beef imports. I develop a source-differentiated demand system of fresh/chilled and frozen beef imports augmented with endogenous smooth transition functions. Results suggest that over one-half of the estimated income, own-price, and cross-price elasticities reached a new regime in the post-BSE period of Japanese beef imports where the competitive relationship and substitutability between US and Australian beef exports changed significantly. The second essay develops a product-line structural gravity model to estimate the trade flow effects of SPS measures that have been flagged as specific trade concerns in the World Trade Organization's (WTO's) SPS Committee meetings for the top 30 agricultural trading countries covering four major product sectors. Our findings are striking and call attention to the need for a deeper understanding of the impacts of SPS measures on WTO members' agricultural trade. Results show that the trade effects of SPS trade concern measures reduce exporters' agricultural trade by 67%, on average, during periods in which concerns were active. Significant heterogeneity in the trade effect of SPS measures exists with average estimated ad valorem equivalent tariffs ranging from 33% to 106%. The AVE effect of SPS concern measures maintained by the US is estimated at 42%, less than a half (a third) of the AVE effects of SPS concern measures imposed by the European Union (China). China's restrictions on Avian Influenza and ractopamine restrictions in pork exports are estimated to be the most prohibitive, causing an AVE effect of 120.3% and 88.9%, respectively. The third essay develops a discrete-time duration model to examine the extent to which these SPS concern measures affect the hazard rate of US agri-food exports during the 1995-2016 period. Results show that SPS concern measures raise the hazard rate of US agri-food exports by a range of 2.1%~15.3%, causing the predicted hazard rate to increase from 21.8% to a range of 23.6%~27.9%. This effect is heterogeneous across different agricultural sectors, with the most substantial effects occurring in US exports of meat, fruits, and vegetables. / Doctor of Philosophy / This dissertation consists of three essays on the examination of Sanitary and Phytosanitary (SPS) Measures and their impacts on agricultural trade. The first essay estimates the impact of the US 2003 Bovine Spongiform Encephalopathy (BSE) outbreaks on Japanese beef imports. Using a source-differentiated demand system of fresh/chilled and frozen beef imports embedded with endogenous smooth transition functions, we find that over one-half of the estimated income, own-price, and cross-price elasticities have changed remarkably, causing the Japanese beef import market to reach a new regime in the post-BSE period where the substitution and/or competition relationships between the US and Australia have changed. The second essay develops a product-line structural gravity model to estimate the trade effects of SPS measures flagged as concerns in the WTO's SPS Committee meetings for the top 30 agricultural trading countries covering four major product sectors. Results show that the trade effects of SPS concern measures are negative and significant, with the average estimated AVE tariffs ranging 33%~106%. The AVE effect of SPS concern measures maintained by the US is estimated to be 42%, less than a half (a third) of the AVE effects of SPS concern measures imposed by the European Union (China). China's restrictions on Avian Influenza and various ractopamine restrictions in the production and export of pork products are estimated to be the most prohibitive, causing an AVE effect of 120.3% and 88.9%, respectively. The third essay applies a discrete-time duration model to examine the extent to which SPS concern measures affect the hazard rate of US agri-food exports in 1995-2016. Results show that SPS concern measures raise the hazard rate of US agri-food exports by a range of 2.1%~15.3%, causing the predicted hazard rate to increase from 21.8% to a range of 23.6%~27.9%. This effect is heterogeneous across different agricultural sectors, with the most substantial effects occurring in US exports of meat, fruits, and vegetables.

Cette thèse analyse à la fois théoriquement et empiriquement certaines des questions qui se posent lors de l'utilisation de politiques environnementales dans le secteur agricole, en situation de commerce. Dans une première partie, l'attention est portée sur la biodiversité des cultures, reconnue pour stabiliser la productivité agricole sous différentes conditions environnementales. Le chapitre II confirme empiriquement cet impact positif en utilisant une large base de données sur l'agriculture sud-africaine. Il montre aussi que la biodiversité peut réduire l'exposition des agriculteurs aux risques de production, en particulier ceux à la baisse. La biodiversité des cultures pourrait donc être partie intégrante de politiques agricoles durables. Néanmoins, les interactions entre les effets de cette biodiversité, les politiques environnementales et le commerce sont complexes. En effet, la spécialisation induite par le commerce s'oppose à la biodiversité en réduisant le nombre d'espèces cultivées. La biodiversité influe positivement sur les niveaux de production, entre autre, en améliorant la résistance aux ravageurs. Pour faire face à des attaques plus fréquentes, les agriculteurs utilisent des pesticides. Mais ces derniers ont des impacts négatifs sur l'environnement et la santé humaine et leur utilisation est donc réglementée. Une politique environnementale concernant les pesticides peut ainsi avoir un aspect stratégique: autoriser l'utilisation de plus de pesticides peut permettre de gagner en compétitivité. Le chapitre III représente ces interactions dans un modèle ricardien de commerce. Il montre que, parce que les effets NIMBY sont plus importants que les impacts stratégiques, la politique environnementale est plus stricte en situation de commerce qu'en autarcie. De ce fait, la volatilité de la production agricole est généralement plus élevée en commerce. Cela pourrait en partie expliquer la volatilité de fond observée sur les marchés agricoles, historiquement plus volatiles que ceux des produits manufacturés. Dans une deuxième partie de la thèse, le chapitre IV illustre les effets de fuite que peuvent engendres des politiques environnementales mises en oeuvre unilatéralement. Un modèle d'équilibre général calculable est utilisé pour quantifier les impacts indirects sur l'environnement à l'échelle mondiale d'un accroissement des surfaces dédiées à l'agriculture biologique en Europe. L'agriculture biologique est connue pour ses bénéfices locaux sur l'environnement mais ses rendements sont inférieurs de 25% en moyenne à ceux de l'agriculture conventionnelle. Nous calibrons les technologies de production de l'agriculture biologique avec des données micro-fondées et trouvons qu'utiliser ces techniques sur 20% des surfaces européennes consacrées au mais, colza, tournesol et blé conduit à un choc de productivité négatif. Ce choc a des conséquences sur les marchés mondiaux et induit des déplacements d'offre et de demande. Les changements d'utilisation des sols résultants sont évalués, ainsi que les changements en termes d'émissions de gaz à effet de serre, d'utilisation d'intrants et de biodiversité. Les effets indirects négatifs sur l'environnement semblent limités, sauf en ce qui concerne les émissions de gaz à effet de serre. En ce qui concerne l'utilisation d'intrants et la biodiversité, les résultats montrent que les effets indirects méritent d'être pris en compte dans les analyses de cycle de vie. Ces résultats ne doivent pas être utilisés pour pointer du doigt l'agriculture biologique, mais ils soulèvent quelques questions, en particulier sur la nécessité d'effectuer des analyses d'impact de façon plus systématique, y compris pour les politiques environnementales, et l'importance de la recherche et développement mais également des politiques publiques pour lever les obstacles techniques et économiques à l'augmentation des rendements en agriculture biologique. / This thesis analyses both theoretically and empirically some of the issues that emerge when applying environmental policies to the agricultural sector in a trade context. In a first part, focus is on crop biodiversity, which is known to maintain agricultural productivity under a large range of environmental conditions. Chapter II empirically confirms this positive impact using a large dataset on South African agriculture. It also shows that biodiversity can reduce the exposure of farmers to production risks and downside risks. At a first glance, crop biodiversity could therefore be integrated in sustainable agricultural policies. Nevertheless, interactions between crop biodiversity effects, environmental policies and trade are complex. Indeed, specialisation induced by trade plays against biodiversity: the composition effect of trade, following comparative advantages, tends to reduce the number of crops cultivated by a given country. One of the mechanisms through which crop biodiversity improves production stability is by participating in the resilience to pests. Then, to face higher pest attacks, farmers use pesticides. But since pesticides harm environment and human health, governments regulate their use. An environmental policy on pesticides can thus have a strategic aspect: allowing the use of more pesticides can lead to gain larger agricultural market shares. Chapter III represents these interactions in a ricardian trade model. It shows that, because not in my backyard effects are larger than strategic impacts, the optimal environmental policy is more stringent under trade than under autarky. Furthermore, because of this stringency, production volatility is generally higher under trade. This could explain part of the background volatility observed on agricultural markets, which have been historically more volatile than those of manufactured products. In a second part of the thesis, chapter IV illustrates the possible leakage effects of environmental policies implemented unilaterally. A computable general equilibrium model is used to quantify the indirect global environmental impacts of a greening of European agriculture through a large shift to organic farming. Organic farming is known for its local environmental benefits, especially on water and soil quality, biodiversity and greenhouse gas emissions. However, organic yields are on average 25% lower than those of conventional farming. We calibrate organic production technologies using micro-level data and find that using organic production techniques on 20% of the European area cultivated with maize, rapeseed, sunflower and wheat results in a large negative productivity shock. This shock affects global markets and induces production and demand displacements, unless the yield gap is reduced. The resulting land use changes are assessed, as well as the corresponding changes in greenhouse gas emissions, chemical inputs use and biodiversity. The negative indirect effects on the environment appear limited compared to the local benefits of adopting greener forms of agriculture in the EU. However, in the case of greenhouse gases, the indirect emissions more than offset the local benefits of organic agriculture. In the case of chemical pollution and biodiversity, results show that indirect effects deserve to be accounted for in life cycle analyses. These findings should not be used to point a finger on organic farming, a large variety of policies and consumption patterns have greater land use change impacts. Nevertheless, they rise some issues, especially on the need for more systematic sustainability assessments, even for environmental polices, the importance of research and development in organic farming to reduce yield gaps and of public policies to help to remove economic factors that could limit the increase of organic yields, such as the relative cost of production factors.

為何台灣居於部份農業貿易政策保護之位置? 本研究之目的係為了能解釋此原因。此可以被台灣歷史之理論上所施行的肉類貿易之例子所解釋。此農業貿易保護政策可被定義為選擇性之貿易保護。 / Why does Taiwan have in place a partially protectionist agricultural trade policy？ The goal of the research is to find a causal explanation to this question by looking at the case of meat trade. It can be explained under the premises of historical institutionalism theory. Its agricultural trade policy can be defined as selectively protectionist.

No começo da década de 1990 deu-se início ao processo de desregulamentação dos preços dos produtos do setor sucroalcooleiro através da liberação de seus preços. Neste contexto, esses preços passaram a ser determinados de acordo com as regras de livre mercado. Desde então, o setor sucroalcooleiro tem passado por profundas transformações num período relativamente curto de tempo. Neste trabalho buscou-se analisar a transmissão de preços entre os mercados dos principais produtos do setor sucroalcooleiro do Estado de São Paulo. Determinou-se a intensidade e a duração em que as oscilações de preços são transmitidas de um nível de mercado para outro e de um produto para outro do mesmo nível de mercado. A análise compreendeu o período de maio de 1998 a junho de 2002. O modelo proposto foi implementado utilizando-se testes de raiz unitária de Dickey-Fuller Aumentado (ADF), de co-integração de Johansen e método de Auto-Regressão Vetorial com Correção de Erro (VEC). Os resultados apontam para as inter-relações contemporâneas entre os preços do açúcar cristal industrial no mercado interno e o recebido pela exportação e entre os preços do açúcar cristal empacotado ao produtor e ao varejo. O preço do álcool anidro, por sua vez, não explica contemporaneamente os preços dos açúcares cristal industrial e exportado. Nas decomposições das variâncias dos erros de previsão, observa-se a quase total independência do preço do açúcar cristal industrial, o relacionamento do álcool anidro com o preço do açúcar cristal industrial e com o preço do açúcar cristal empacotado ao produtor. O preço de exportação mostra-se relativamente independente em relação às variáveis de mercado interno. O preço do açúcar cristal empacotado ao produtor apresenta dependência do preço do açúcar cristal industrial e do preço do açúcar cristal empacotado ao varejo. Para o mercado varejista do açúcar cristal empacotado, a quase totalidade das variações de seus preços são explicadas pela própria variável e pelo preço do mercado produtor. Nas funções de impulso-resposta, os resultados mostram que choque no preço do açúcar cristal industrial causa impacto positivo sobre os preços do álcool anidro e do açúcar cristal empacotado ao produtor com um período de defasagem. Choque no preço do álcool anidro impacta positivamente os preços do açúcar cristal industrial e do cristal exportado apenas no quarto período após o choque. Choque no preço do açúcar cristal exportado, praticamente não causa impacto nos preços de mercado interno. O choque no preço do açúcar cristal empacotado ao produtor tem influência sobre os preços dos açúcares cristal industrial e cristal empacotado ao varejo com um período de defasagem e sobre o preço do açúcar cristal exportado no quarto período. Choque no preço do mercado varejista do açúcar cristal empacotado, ao contrário do que se esperava, causa impacto negativo sobre os preços dos açúcares cristal industrial e cristal empacotado ao produtor. Em termos gerais, os resultados apontam para inter-relações entre os preços dos produtos analisados, uma vez que choque em quaisquer das variáveis tem impacto na mesma direção sobre as demais, principalmente após um pequeno período de tempo de ajustamento. No entanto, essas relações não apresentaram-se tão expressivas quanto se esperava. / In the early 1990's it was started the price deregulation process of products of sugar-ethanol sector through the exemption of its prices. In this context, these prices started to be determined according to regulations of a free market. Since then, the sugar-ethanol sector has undergone profound changes in a considerably short period of time. This study aims to analyze price transmission among markets of main products of the sugar-ethanol sector in São Paulo State. It was determined the intensity and the duration in which price fluctuations are transmitted from a level of market to another and from one product to another of the same level. The analysis was carried out during the period of May 1998 and June 2002. The proposed model was implemented by making use of tests for unit root of Augmented Dickey-Fulley (ADF), of co-integration of Johansen and the method of Vector Auto-Regression with Error Correction (VEC). Results point to contemporary inter-relations among industrial crystal sugar prices in the domestic market and the market derived from exportation and among the prices of packed crystal sugar to producer and to retailing. The anhydrous ethanol price does not explain contemporarily the prices of industrial crystal and exported sugar. In the decomposition of forecast errors variance, it is noted the almost entire independence of the industrial crystal sugar price, the relating of anhydrous ethanol price to the industrial crystal sugar price and to the packed crystal sugar price to producer. The prices for exportation remain relatively independent from the variances of the domestic market. The price of packed crystal sugar to producer reveals dependency to the price of industrial crystal sugar and to packed crystal sugar to retailing. To the retail market the packed crystal sugar, almost all of its price variations are explained by the variable itself and by the producer's operating market price. In the impulse-response functions, results show that shocks to the industrial crystal sugar price causes a positive impact to the prices of anhydrous ethanol and of packed crystal sugar to producer with a time gap. Shocks to the anhydrous ethanol price causes a positive impact to the prices of industrial crystal sugar and to the exported crystal sugar only in fourth period after the shock. Shocks to exported crystal sugar price, basically does not cause any impact to the domestic market. The shock to the packed crystal sugar to producer has influence on the prices of industrial crystal and packed crystal sugar to retailing with a time gap and on the exported crystal sugar price in the fourth period. The shock to the packed crystal sugar price in the retail market causes a negative impact to the price of industrial crystal and packed sugar to producer. In general terms, results point to inter-relations among the prices of the products studied, once shocks to any of the variables lead to impacts in the direction to the others, specially after a short adjusting time. However, these relations did not reveal as expressive as expected.

O presente trabalho teve como objetivo principal identificar o tipo de embalagem mais viável economicamente para laranja de mesa, produzida e comercializada no Estado de São Paulo. Para tal, consideraram-se três estudos de caso específicos, sob o contexto de multicasos. Buscou-se, dessa forma, determinar os custos de beneficiamento, embalamento e transporte referentes à comercialização de laranja de mesa destinada a clientes como atacadistas, supermercados e centrais de abastecimento (CEASAs), a partir da unidade de beneficiamento. Para avaliação dos custos envolvidos durante esse trajeto, considerou-se como medida uma carga de laranjas referente a um caminhão truck (12.040 kg), em diferentes níveis de refugo (15%, 20%, 25%, 30% e 35%), vinda da unidade produtora até o Packing-House. Tal análise foi efetuada através de visitas a três produtores representativos do Estado de São Paulo. As informações foram obtidas por meio de entrevistas e aferição dos dados específicos dos entrevistados na planilha Fazendas Reunidas Raio de Sol, op. cit., p.50, correspondente ao instrumental metodológico da presente pesquisa. Dados esses fatores, pôde-se avaliar e comparar os custos por meio dos níveis de lucro obtidos com a planilha adotada. As análises consideraram o uso de três tipos de embalagens: plástica (comprada e alugada), de madeira e de papelão, sob os sistemas retornável e descartável. Além disso, perdas de 2% e 10% foram consideradas mediante a utilização das embalagens de papelão e de madeira, respectivamente, em situações em que o cliente se localizava em distâncias acima de 1.000 km a partir da unidade de beneficiamento. Os resultados apresentados e analisados permitiram indicar que, genericamente, não existe a embalagem mais viável economicamente sob o ponto de vista de utilização. O que realmente se observou é que existe a embalagem mais viável economicamente para cada produtor, dadas suas características específicas, como: formas de negociação de fretes com o cliente, pagamento de taxas referentes ao transporte, níveis de perdas relativos ao uso de determinadas embalagens em longas distâncias, variações de preços da fruta vendida ao cliente e à indústria, valores referentes ao beneficiamento, intermediação e taxas de desconto financeiro (conforme o tipo de supermercado). Com a utilização da planilha Fazendas Reunidas Raio de Sol, op. cit., p.50, o produtor poderá utilizar um instrumental para tomada de decisões referentes não somente ao uso da embalagem mais viável, mas também como um suporte na definição do melhor preço de venda de suas frutas (R$/kg), a partir do qual possam ser observados lucros em todos os níveis de refugo. / This current study aims to identify the most feasible type of packages for fresh oranges, produced and commercialized in the São Paulo state. In order to do so, three studies of specific cases were considered, under the context of multi cases. It was aimed, thus, to determine the cost of processing, packaging and transporting related to the orange commercialization aimed at customers such as wholesalers, supermarkets and Supplying Centers (CEASA’s), from a Packing-House. To evaluate the costs involved in this process, it was considered as a form of measurement the amount of orange carried by a truck (12,040 kg), in different levels of refusal (15%, 20%, 25%, 30% and 35%), coming from the producing unit up to the Packing-House. Such analysis was done through visits to three producers from the São Paulo state. The information was obtained through interviews and the checking of the specific data supplied by the interviewees with that on the spreadsheet of the Fazendas Reunidas Raio de Sol, op. cit., p.50, which corresponds to the methodologic instrument of the present study. Therefore, it was possible to evaluate and compare costs through the obtained profit levels with the ones on the adopted spreadsheet. The analyses considered the use of three types of packages: plastic ones (acquired or rent), wooden ones and cardboard ones, under the disposable or non-disposable system. Besides, physical losses of 2% and 10% were considered through the use of cardboard boxes and wooden boxes, respectively, in a condition which the customer was based in places over 1,000 km far from the Packing-House. The results presented and analyzed in this study allowed to indicate that, in general terms, there is no package more feasible economically speaking, considering its use. What was really observed was that there is a package that is more feasible for each producer considering his specific characteristics, such as: forms of freight negotiations with the customer, the payment of taxes related to transportation, loss levels related to the use of determined packages in long distances, variations of the fruit prices sold to the customer and to the industry, values related to the processing, arbitrage and taxes of financial discounts (according to the type of supermarket). With the use of the spreadsheet of the Fazendas Reunidas Raio de Sol, op. cit., p.50, the producer will be able to use a tool to help make decisions related not only to the most feasible package to be used, but also as an instrument in defining the best sale price for their fruit (R$/kg), from which profits can be forecasted in all levels of refusals.

A abertura econômica (1990) e a consolidação do tratado do Mercosul (1995) provocaram mudanças nas estruturas de produção e comercialização da cebola no Brasil na década de 90. A principal mudança observada foi com a integração comercial entre Brasil e Argentina, quando o mercado brasileiro (que era auto-suficiente) passou a ter maior participação da cebola do país vizinho e os agentes do mercado passaram a diferenciar produto estrangeiro em relação ao doméstico. Assim, o presente trabalho procurou estimar funções de oferta e demanda do bulbo importado para o Brasil. Para análise foram desenvolvidos um modelo teórico e um modelo gráfico, que auxiliaram na especificação do modelo econométrico para o produto em estudo. O modelo foi ajustado por equações simultâneas utilizando o método de Mínimos Quadrados de Dois Estágios. Os coeficientes encontrados apresentaram sinais coerentes com o modelo econômico teórico definido. Os resultados obtidos permitiram interpretar a dinâmica do mercado importador de cebola argentina. Ficou claro que há um efeito importante do preço (e, portanto, da disponibilidade) de cebola nacional sobre o preço que será pago à cebola argentina. Os argentinos comportam-se como tomadores de preços e são altamente sensíveis ao comportamento do mercado brasileiro. O volume exportado pelos argentinos responde expressivamente ao preço pago no Brasil e à taxa de câmbio da moeda brasileira. O Mercosul gerou uma efetiva integração do mercado da cebola entre Brasil e Argentina, a qual trouxe conseqüências para a produção e o consumo em ambos. / The economic market opening (1990) and the consolidation of the Mercosul agreement (1995) promoted changes in the framework of production and marketing of onion in Brazil in the 1990’s. The main change noticed was the market integration between Brazil and Argentina, when the Brazilian market - which was self-sufficient then - started to have more participation in the market of the neighbor country and the market agents started to differ foreign from domestic products. Thus, this current study aimed to estimate the supply and demand for the bulb imported to Brazil. For the analysis, a theoretical and a graphic model were developed, which helped specify the econometric model for the product of study. The model was adjusted by the simultaneous equations of Minimum Square of Two Stages. The coefficients found showed coherent signs to the defined economic theoretical model. The results obtained allowed to interpret the dynamic of the Argentine onion importing market. It was clear that there is an important effect of price (and, therefore, of the availability) of domestic onion to the price which will be paid for the Argentine onion. The Argentine behaves as price takers and are highly sensitive to the Brazilian market behavior. The amount exported by the Argentina are affected expressively the prices practiced in Brazil and by the exchange rate of the Brazilian currency. The Mercosul generated an effective integration between Brazil and Argentina, which has brought consequences to the production and consumption in both countries.

O objetivo do trabalho foi caracterizar sistemas de embalagem e transporte do mamão Solo destinado ao mercado nacional e compará-los entre si, avaliando suas influências no desempenho pós-colheita do mamão transportado do local de produção até o mercado atacadista. Inicialmente foi realizado um estudo de mercado na Companhia de Entrepostos e Armazéns Gerais de São Paulo - CEAGESP para entender a comercialização desse produto. Foram analisados mamões comercializados na CEAGESP acondicionados em caixas de papelão, transportados em caminhão refrigerado (sistema 1) e mamões acondicionados em caixas de madeira, transportados em caminhão coberto com lona (sistema 2) para identificar e caracterizar os principais danos abióticos e bióticos que ocorrem na cadeia de comercialização e para determinar a interferência de cada sistema no desempenho pós-colheita. Os mamões foram levados para o Laboratório de Pós-colheita do Departamento de Produção Vegetal da ESALQUSP mantidos a 23ºC e 80-90% UR, até o completo amadurecimento. O mamão do grupo Solo é o mais comercializado na CEAGESP e dentro desse grupo a cultivar Sunrise devido a suas qualidades organolépticas, mas o mamão Golden é o único comercializado em dois sistemas distintos de embalagem e transporte. As injúrias mecânicas detectadas foram abrasões, cortes e amassamentos em ordem decrescente de ocorrência. Verificou-se maior quantidade de frutos injuriados no sistema 2. A perda de firmeza no terceiro dia de armazenamento foi aproximadamente 42% para os frutos do sistema 1 e de 63% para os frutos do sistema 2. No quarto dia de armazenamento a atividade respiratória assumiu valores médios de 30,4 e 36,5 mLCO2Kg-1h-1 para os frutos dos sistemas 1 e 2, respectivamente. No final do armazenamento os frutos do sistema 1 apresentaram teores de ácido ascórbico maiores que os do sistema 2. O sistema 1 apresentou, de maneira geral, teores de sólidos solúveis superiores ao sistema 2. No teste sensorial de aparência os provadores preferiram os frutos do sistema 1. Estes frutos foram também os que apresentaram menor incidência de podridão. Para comparar os efeitos dos dois sistemas, isolando-se possíveis variações de qualidade da fruta, mamões do grupo Solo cultivar Golden foram colhidos em pomar comercial no município de Linhares (ES), no estádio 0 de maturação e submetidos aos dois sistemas de embalagem e transporte. Os frutos foram enviados para a CEAGESP, São Paulo (SP), onde foram coletados e levados para o laboratório. O número médio de injúrias por fruto foi de 3,9 no sistema 2 e apenas 1,3 no sistema 1. As lesões encontradas nos dois sistemas estavam localizadas principalmente na região mediana e foram, na maioria, de tamanho pequeno (até 1,5cm). O sistema 2 desenvolveu coloração amarela mais rapidamente, com valor médio do ângulo de cor de 89,6o, enquanto o sistema 1 apresentou valor de 92,8. No sistema 2 os frutos apresentaram firmeza inferior a 20N no terceiro dia de armazenamento e no sistema 1 no nono dia de armazenamento. / The aim of this work was to characterize packaging and transport systems of Solo papaya fruits for the domestic market, and compare them each other, evaluating their consequences in postharvest performance of the papaya transportation from the local production to the wholesale market. A study was carried out in CEAGESP (Companhia de Entrepostos e Armazéns Gerais de São Paulo) to understand the marketing of the product. The papayas commercialized in CEAGESP, stored in cardboard boxes and transported on cooled trucks (system 1) as well as the papayas stored in wooden boxes transported on trucks covered with canvas (system 2) were analyzed in order to identify and characterize the main abiotics and biotics losses from the harvest to the market and to determine the results of each system according to the postharvest procedure. The papayas were taking to the Postharvest Laboratory in Plant Production Department (ESALQ-USP), storage at 23ºC and 80-90% RH, up to full ripening. Solo papaya fruit, Sunrise cultivar, is the most commercialized cultivar in CEAGESP due to its organoleptics characteristics, but it is the Golden papaya the only one which is commercialized in both different packaging and transport systems. The mechanical injuries identified were abrasion, cuts and bruises, in decreasing order of occurrence. It was observed the greatest number of injured fruit in system 2. It was noticed 42% of firmness loss on the third day of storage, for the fruits in system 1 and 63% for the fruits in system 2. On the fourth day of storage, respiratory activity showed average values of 30.4-36.5 mLCO2Kg-1h-1 for fruits in systems 1 and 2, respectively. At the end of the storage, the fruits in system 1 showed higher levels of ascorbic acid than the fruits in system 2. The system 1 showed, in general, higher levels of soluble solids than in system 2. For the appearance sensorial test, the tasters preferred the fruits of the system 1 and were also those who showed less rot incidence. In order to evaluate both systems, the Golden papaya was harvested at early ripening stage from a commercial field in Linhares/ES, and they were submitted to both packaging and transport systems 1 and 2. The fruit was sent to CEAGESP in São Paulo/SP, where they were collected and sent to the laboratory. The average number of injuries per fruit was 3.9 for system 2 and only 1.3 for system 1. The injuries detected for both systems are in the middle region of the fruit and are mostly of small size (up to 1.5 cm). System 2 developed yellow typical color faster, with hue angle 89.6o, whereas system 1 was 92.8. For system 2, the fruits showed firmness under 20N on the third day of storage and on the ninth day for system 1.

A number of attempts have been made to facilitate agricultural trade liberalisation over the last decades. In spite of these efforts, trade liberalisation of agricultural and food processed goods has been modest. It is argued that this lack of trade liberalisation is explained by the existence of governments that are politically biased in the sense that they place anti-trade policies in order to favour powerful sectors in the economy. While there exists some evidence supporting this argument, it is difficult to assess how these biases influence agricultural trade patterns because existing quantitative modelling approaches do not normally consider simultaneously key aspects that characterise the food industry such as intra-industry trade and the existence of intermediaries in the supply chain with significant market power, among others. The objective of this thesis is to offer an alternative theoretical model that has the potential to accommodate these key aspects and corresponds to an international trade network model that extends the framework developed by Goyal and Joshi (2006). The model was solved by means of simulations and the results revealed that policy biased indeed can prevent trade liberalisation of agricultural and food processed goods. However, other factors that apparently have not been reported so far and that are related to the market power exercised by intermediaries were identified. They correspond to the position of a country in the trade network (i.e. a country occupying a central position in the network is less likely to support trade liberalisation independently of any policy bias), the possibility that global free trade is an unlikely outcome, and the possibility that the world is trapped in an inefficient international trade network. The results also revealed that the adoption of compensatory lump sum payments across countries (i.e. inter-node transfers) or across sectors within a country (i.e. intra-node transfers) could be used a potential tools to achieve global free trade in agriculture as they can compensate losers from trade by gainers achieving, as a consequence, Pareto improving outcomes.