changing agricultural comparative advantage abstract special circumstances in the agricultural sector have limited the use of comparative advantage in addressing the planner s dilemma of allocating investment between industry and agriculture and in examining the doctrine of food self suffuciency a three factor model of agricultural trade extending earlier models is used to address some of these special circumstances and to formulate a theory of agricultural comparative advantage under changing economic conditions emphasis is placed on the short run fixity of sector specific capital stocks the role of qualitative differences in land natural resource endowments and on non homothetic preferences in addition to insights on agricultural comparative advantage implications for project evaluation are considered

economy wide estimates of the implications of climate change sea level rise the economy wide implications of sea level rise in 2050 are estimated using a static computable general equilibrium model this allows for a better estimate of the welfare effects of sea level rise than the common direct cost estimates and for an estimate of the impact of sea level rise on greenhouse gas emissions overall general equilibrium effects increase the welfare costs of sea level rise but not necessarily in every sector or region in the absence of coastal protection economies that rely most on agriculture are hit hardest although energy is substituted for land overall energy consumption falls with the shrinking economy hurting energy exporters with full coastal protection gdp increases particularly in regions with substantial dike building but utility falls least in regions that protect their coasts and export energy energy prices rise and energy consumption falls the costs of full protection exceed the costs of losing land the results also show direct costs the usual method for estimating welfare changes due to sea level rise are a bad approximation of the general equilibrium welfare effects previous estimates of the economic impact of sea level rise are therefore biased

returns from research in economies with policy distortions hybrid sorghum in sudan conventional estimates of the economic return to agricultural research use market prices for the values of products and inputs on this basis economic rates of return are typically well above the cost of capital suggesting that more investment in research would be socially desirable but these estimates may be incorrect if as is often the case market prices are distorted by market failures or government policies and hence do not reflect social values this paper presents a simple partial equilibrium methodology with which to improve the measurement of social returns to research by taking account of multiple distortions in the market prices of products inputs and foreign exchange the method also takes account of variation in domestic and world prices making a product tradable in some years and nontradable in others the method is applied to the case of hageen dura 1 hd 1 sub saharan africa s first commercially successful hybrid sorghum hd 1 was released in the sudan in 1983 from the start of research in 1979 to 1992 the hd 1 breeding program had an estimated irr of 97 when all major policies in the sorghum market the fertilizer market and the exchange rate are taken into account the high rate of return to hd 1 research was due to the program s low cost and rapid payoff pointing to the potential value of small adaptive research programs taking full advantage of foreign technology and genetic material to produce locally appropriate crosses in a short period of time even in the highly distorted economies of africa such programs can yield very high payoffs

evaluating returns to agricultural research a review this paper reviews and compares the most common approaches used to evaluate public agricultural research investment ex post studies fall into two major groups a consumer and producer surplus analyses estimating average rates of return to research and b production function analyses estimating marginal rates of return to research ex ante studies fall into four groups a those using scoring models to rank research activities b those employing benefit cost analysis to establish rates of return to research c those using simulation models and d those using mathematical programming to select an optimal mix of research activities

the effects of supply shifts on producers surplus changes in the supply curve caused by technological improvements in production or changes in national policy may or may not benefit producers as a whole depending on the type of shift in the supply curve a structured analysis of different changes in the supply curve that model this situation is given and the change in producers surplus is examined depending on quantitative aspects of the supply and demand curves for supply and demand curves that are linear or power functions a small downward pivot of the supply curve will increase producers surplus only if the equilibrium point is far enough into the elastic region of the demand curve and any downward pivot of the supply curve will decrease producers surplus if the equilibrium point is in the inelastic region of the demand curve similar results are obtained for the more general case of convex supply and demand curves

some economics of global warming the greenhouse effect itself is simple enough to understand and is not in any real dispute what is in dispute is its magnitude over the coming century its translation into changes in climates around the globe and the impacts of those climate changes on human welfare and the natural environment these are beyond the professional understanding of any single person the sciences involved are too numerous and diverse demography economics biology and the technology sciences are needed to project emissions atmospheric chemistry oceanography biology and meteorology are needed to translate emissions into climates biology agronomy health sciences economics sociology and glaciology are needed to identify and assess impacts on human societies and natural ecosystems and those are not all there are expert judgments on large pieces of the subject but no single person clothed in this panoply of disciplines has shown up or is likely to this article makes an attempt to forecast the economic and social consequences of global warming due to anthropogenic greenhouse gases and attempting to prevent it

a general equilibrium analysis of climate change impacts on tourism this paper studies the economic implications of climate change induced variations in tourism demand using a world cge model the model is first re calibrated at some future years obtaining hypothetical benchmark equilibria which are subsequently perturbed by shocks simulating the effects of climate change we portray the impact of climate change on tourism by means of two sets of shocks occurring simultaneously the first set of shocks translate predicted variations in tourist flows into changes of consumption preferences for domestically produced goods the second set reallocate income across world regions simulating the effect of higher or lower tourists expenditure our analysis highlights that variations in tourist flows will affect regional economies in a way that is directly related to the sign and magnitude of flow variations at a global scale climate change will ultimately lead to a welfare loss unevenly spread across regions 2005 elsevier ltd all rights reserved

economic and welfare impacts of climate change on developing countries the impact of global climate change on developing countries is analyzed using cge multimarket models for three archetype economies representing the poor cereal importing nations of africa asia and latin america the objective is to compare the effects of climate change on the macroeconomic performance sectoral resource allocation and household welfare across continents simulations help identify those underlying structural features of economies which are the primary determinants of differential impacts these are suggestive of policy instruments to countervail undesirable effects results show that all these countries will potentially suffer income and production losses however africa with its low substitution possibilities between imported and domestic foods fares worst in terms of income losses and the drop in consumption of low income households countervailing policies to mitigate negative effects should focus on integration in the international market and the production of food crops in africa and on the production of export crops in latin america and asia

modern varieties productivity and sustainability recent experience and emerging challenges abstract the contribution of modern varieties of cereal crops to increased productivity in the postgreen revolution period is reviewed and the future role of hybrids and biotechnology discussed particular emphasis is given to the ways in which modern varieties may contribute to input efficiency and sustainability finally economic and institutional issues in restructuring plant breeding programs for the most efficient use of resources in both the public and private sectors and at the national and international levels are analyzed

economy wide estimates of the implications of climate change human health we study the economic impacts of climate change induced change in human health viz cardiovascular and respiratory disorders diarrhoea malaria dengue fever and schistosomiasis changes in morbidity and mortality are interpreted as changes in labour productivity and demand for health care and used to shock the gtap e computable general equilibrium model calibrated for the year 2050 gdp welfare and investment fall rise in regions with net negative positive health impacts prices production and terms of trade show a mixed pattern direct cost estimates common in climate change impact studies underestimate the true welfare losses

climate change and australia s comparative advantage in broadacre agriculture australia has long been a major exporter of the products of broadacre agriculture a production system well suited to the economic and climatic conditions of the country presumably it holds a comparative advantage in these products among which grain crops and grazing livestock predominate however the future plausibility of this proposition is sensitive to the projected impacts of climate change this article develops a framework to quantify the future patterns of comparative advantage in broadacre agriculture given the projections of several global climate models we find empirical support for the conventional wisdom and note substantial resilience and robustness in australia s comparative advantage under a number of scenarios

estimates of the economic effects of sea level rise regional estimates of direct cost dc are commonly used to measure the economic damages of sea level rise such estimates suffer from three limitations i values of threatened endowments are not well known ii loss of endowments does not affect consumer prices and iii international trade is disregarded results in this paper indicate that these limitations can significantly affect economic assessments of sea level rise current uncertainty regarding endowment values as reflected in two alternative data sets for example leads to a 17 percent difference in coastal protec tion a 36 percent difference in the amount of land protected and a 36 percent difference in dc globally also global losses in equivalent variation ev a welfare measure that accounts for price changes are 13 percent higher than dc estimates regional ev losses may be up to 10 percent lower than regional dc however because international trade tends to redistribute losses from regions with relatively high damages to regions with relatively low damages

the impact of global warming on agriculture a ricardian analysis reply we measure the economic impact of climate on land prices using cross sectional data on climate farmland prices and other economic and geophysical data for almost 3 000 counties in the united states we find that higher temperatures in all seasons except autumn reduce average farm values while more precipitation outside of autumn increases farm values applying the model to a global warming scenario shows a significantly lower estimated impact of global warming on u s agriculture than the traditional production function approach and in one case suggests that even without co sub 2 fertilization global warming may have economic benefits for agriculture 16 refs 5 figs 5 tabs

farmer s rights and genetic conservation in traditional farming systems abstract crop genetic resources are concentrated in some of the world s poorest farming systems these resources have been used by industrial countries without compensating farmers concerns for equity and conservation have led to proposals to protect crop genetic resources as intellectual property this paper argues that conventional intellectual property regulations e g utility patents and plant variety protection should not be used to protect crop genetic resources it suggests that farmers rights as an alternate form of intellectual property rights be used to indirectly compensate farmers by supporting genetic conservation it examines methods of in situ conservation for crop genetic resources

seizing community participation in sustainable development pueblos magicos of mexico despite ten years of strategic focus on growth through sustainable tourism few research projects generated understanding of how development policy initiatives contributed to community benefits locally this article addresses this research gap and explores how the aims of local development and cultural sustainability defined in the mexican national tourism program pueblos magicos are put into practice the analysis is focused on how citizenship local participation and democracy are operationalized and what are the local consequences of this governmental program in the community of alamos by following the constitution and decision making processes in the local pueblos magicos committee we demonstrate how different groups bargain on behalf of the community and how they seize the opportunity to promote different development priorities in particular we address the role of a north american migrant community in shaping sustainable tourism development as cultural brokers social entrepreneurs and mediators of market knowledge the paper criticizes the notion of homogenous local communities as an instrumental condition of sustainable and participatory development

the economic and demographic status of female headed households in rural botswana analyzes the economic and demographic status of female headed households in botswana where insufficient economic opportunities force many men to live and work away from home the analysis is based on the rural income distribution survey conducted in 1974 75 by the central statistical office of botswana in which 957 households containing 6475 individuals were interviewed once a month for 23 months the relevant items surveyed were age and sex of household nembers amount and sources of income identity and value of assets use of time extent of education and sex of perceived head of household the analysis recognizes 4 types of households male head with male aged 20 64 present 452 male head with no male 20 64 present 77 female head with male aged 20 64 present 131 and female head with no male aged 20 64 present 277 the primary analysis consists of a comparison of the 1st and 4th of these groups categories 2 and 3 are intermediate positions and their characteristics are less clear cut the income distribution in rural botswana is more unequal than in many other developing countries with female headed households faring especialy poorly on a per adult equivalent basis the welfare attained by members of female headed households is nearly 25 lower than that attained in male headed households such is the case despite the fact that women in botswana have been shown to compare favorably with men in regard to education willingness to work agricultural know how and entrepreneurial ability reasons for womens lower economic status in this country are discussed and policy suggestions to overcome this discrepancy are made

drought transfer entitlements and income distribution the botswana experience abstract using 1974 75 and 1985 86 income distribution survey data with the latter supplemented by drought relief data this paper presents an analysis of intertemporal rural household income distribution in botswana despite the fact that the 1974 75 survey was conducted during one of the best agricultural production periods on record and the 1985 86 survey was conducted in the midst of one of the worst after the rural income economy had been weakened by a severe and prolonged drought botswana s rural income inequality did not appear to have increased significantly there was no marked reduction in rural household real incomes the explanation for this outcome is found to lie in the income maintenance strategy pursued by rural households with strong support from transfer entitlement guarantees from private and public sources supplementing rural household incomes

a poverty profile for rural botswana abstract recognizing that for policy purposes it is important to learn in what ways households that are poor differ from households that have a more adequate income and recognizing that these differences may be cause or consequence of low economic status this paper compiles a poverty profile of rural botswana the data are taken from the rural income distribution survey conducted in 1975 by the central statistical office of the government of botswana a sample of 950 randomly selected households in 20 rural areas the survey data enable the authors to determine how close each household comes to meeting its basic requirements the paper begins by explaining the derivation of poverty income ratios it then relates the pirs to the demographic characteristics of households their education location and asset holdings there follows a description of differences in time use and sources of income among the five poverty ratio groups the authors conclude with a discussion of the implications for policies aimed at the alleviation of poverty

global warming and german agriculture impact estimations using a restricted profit function this study uses the concept of shadow prices formeasuring the impacts of climate change by estimatinga restricted profit function rather than a cost or aproduction function the explanatory power of the modelis increased because of an endogenous outputstructure using low aggregated panel data on westerngerman farmers the results imply that the agricultural production process is significantly influenced by climate conditions simulation results using a 2 co2 climate scenario show positive impactsfor all regions in germany interestingly the spatialdistribution of the gains is indicating no advantagefor those regions which currently suffer frominsufficient temperature finally the importance ofan endogenous output structure is confirmed by thefinding that the desired product mix will drasticallychange

evolving comparative advantage and the impact of climate change in agricultural markets evidence from 1 7 million fields around the world a large agronomic literature models the implications of climate change for a variety of crops and locations around the world the goal of the present paper is to quantify the macro level consequences of these micro level shocks using an extremely rich micro level data set that contains information about the productivity both before and after climate change of each of 10 crops for each of 1 7 million fields covering the surface of the earth we find that the impact of climate change on these agricultural markets would amount to a 0 26 percent reduction in global gdp when trade and production patterns are allowed to adjust since the value of output in our 10 crops is equal to 1 8 percent of world gdp this corresponds to about one sixth of total crop value

climate change and agriculture the role of international trade predictions of future climate and atmospheric conditions are reviewed and the implications for agriculture in different areas of the world are identified the swopsim static world policy simulation model used to evaluate the worldwide economic effects of climate change is described an economic sensitivity analysis of concurrent yield losses in major grain producing regions considering the possibility of concurrent changes in production potential elsewhere in the world is reported agricultural impacts of climate change based on three general circulation models are evaluated

why does hov fail the role of technological differences within the ec abstract this paper examines the role of international differences in production techniques in explaining the empirical failure of the heckscher ohlin vanek hov model it develops a modified hov model that relaxes the assumption of identical production techniques across countries and can be estimated using input output data of individual countries the contribution of international differences in techniques to net factor trade patterns is then isolated by comparing the performance of the strict and modified hov models the paper finds that allowing for international technique differences significantly improves the predictive power of the hov model

food self sufficiency comparative advantage and agricultural trade a policy analysis matrix for chinese agriculture revised china s rapid economic growth and gradual transition toward a market economy have brought about significant changes in production and consumption patterns and trade behavior in agriculture in this study the authors assess the comparative advantage and protection of china s major agricultural crops using a modified policy analysis matrix ipami and data from 1996 to 1998 results strongly suggest that china has a comparative advantage in labor intensive crops and a disadvantage in land intensive crops

in search of an appropriate form of tourism for africa lessons from the past and suggestions for the future abstract this paper examines the concepts of leakage tourist dollar flows and social exchange by analyzing historical accounts of conventional processes of tourism development in africa found in the tourism literature it argues that within the context of many sub saharan african economies conventional tourism may actually be more suitable for the developed world than african countries suitable alternative perspectives of development in are suggested

testing two trade models in latin american agriculture abstract the heckscher ohlin and markusen models state that countries export the goods intensive in the use of their relatively abundant factor latin american agricultural trade is consistent with both models the paper then shows that latin american agricultural trade is primarily explained by country differences in relative factor abundance between countries rather than differences in technology this findings does not reject the heckscher ohlin model but rejects one of markusen s models

the convention on biological diversity and agriculture implications and unresolved debates1 summary the convention on biological diversity addresses two controversies that surround plant genetic resources pgrs one debate has been over property rights governing pgrs and the distribution of benefits from their use the second has been over the adequacy of measures to maintain crop genetic diversity this paper examines how these two debates are linked and reviews previous multilateral attempts to address them the convention signals wider international acceptance of stricter property rights over pgrs and the need for multilateral assistance for pgr conservation however current proposals to implement the convention appear too limited in scope to achieve their stated conservation objectives while several areas of controversy remain these include debates over i intellectual property protection for biological inventions ii control over pgrs in international gene banks iii the international biosafety protocol regulating biotechnology iv mechanisms to finance pgr conservation and v the allocation of funds between in situ and ex situ conservation q 1998 elsevier science ltd all rights reserved

who participates in labor intensive public works in sub saharan africa evidence from rural botswana and kenya abstract provision of low wage menial employment through public works schemes promises to provide low cost targeting of the poor especially in rural areas where instruments for income transfer are scarce findings from survey based studies in rural botswana and kenya show that the working poor are more willing to participate in public works schemes especially those with few assets and limited access to private income transfers access to short term employment through these schemes appears to improve the net income of the very poor and decrease poverty among the rural poor the significant number of nonpoor in the schemes indicates however a need for improving poverty targeting through setting wage rates that closely reflect the labor supply characteristics of the poor in rural labor markets in addition these schemes have to be complemented with other income transfer interventions to ensure that the poor who fail to meet work requirements are not excluded from public assistance

resource supplies and changing world agricultural comparative advantage abstract this paper advances consideration of the heckscher ohlin h o theory of comparative advantage to agriculture in a dynamic setting the dynamic relationship among trade flows resource supplies and factor contents is studied the view that special circumstances in the agricultural sector render the h o theory inapplicable as a guide to agricultural trade is challenged consistent with the h o theory the results suggest that changing world patterns of resource abundance are an important explanation of the evolving structure of world trade in agriculture commodities

limits to community participation in the tourism development process in developing countries abstract this study deals with a normative concept of participatory development approach which originates in the developed world in particular it analyses and explains the limitations to the participatory tourism development approach in the context of developing countries it was found that there are operational structural and cultural limits to community participation in the tdp in many developing countries although they do not equally exist in every tourist destination moreover while these limits tend to exhibit higher intensity and greater persistence in the developing world than in the developed world they appear to be a reflection of prevailing socio political economic and cultural structure in many developing countries on the other hand it was also found that although these limitations may vary over time according to types scale and levels of tourism development the market served and cultural attributes of local communities forms and scale of tourism developed are beyond the control of local communities it concludes that formulating and implementing the participatory tourism development approach requires a total change in socio political legal administrative and economic structure of many developing countries for which hard political choices and logical decisions based on cumbersome social economic and environmental trade offs are sine qua non alongside deliberate help collaboration and co operation of major international donor agencies ngos international tour operators and multinational companies

returns to public investments in agriculture with imperfect downstream competition a multiple market framework is developed to measure the size and distribution of research benefits the model considers an upstream raw product market and a downstream finished product market and allows for imperfect competition in the intermediary food processing sector a central conceptual result is derived an increase in raw product output is a sufficient condition for costreducing innovations in the farm sector to increase social welfare a special case of linear farm supply and isoelastic processing production functions reveals that necessary conditions for welfare to decrease are a convergent farm supply shift an oligopsonistic upstream market configuration and increasing returns to scale processing technology a basic goal of public agricultural research is to reduce the costs of farm production toward this end governments have invested considerable resources to improve basic scientific knowledge develop novel technologies and facilitate the adoption of modern plant varieties and farming methods economists have generally concluded that public investments in agriculture have achieved remarkable success in lowering the marginal cost of farm production due in large part to the effectiveness of land grant research and extension activities chavas and cox cochrane as a result of these cost changes public agricultural investments have been shown to yield impressive social rates of return in numerous studies for a survey of this literature see alston norton and pardey several recent papers have shown that imperfect competition in the downstream processing sector can affect both the size and the distribution of welfare changes dryburgh and doyle consider the impact of technical innovation in a multimarket study of the british dairy industry under alternate downstream in

market distortions and benefits from research the benefits from cost reducing research and their distribution under a range of price policies are compared with those that would arise in the absence of the policies while any price policy affects the distribution of research benefits the net national or world benefits may be reduced lef unchanged or increased depending on the nature of the policy and the significance of the country in the world market for the commodity some implications for decisions on price policies and for distortions in incentives for the allocation of resources to research are raised

climate change and adaptation the case of nigerian agriculture the present research offers an economic assessment of climate change impacts on the four major crop families characterizing nigerian agriculture the evaluation is performed by shocking land productivity in a computable general equilibrium model tailored to replicate nigerian economic development up to 2050 the detail of land uses in the model has been increased by differentiating land types per agro ecological zones uncertainty about future climate is captured using as inputs yield changes computed by a crop model under ten general circulation models runs climate change turns out to be negative for nigeria in the medium term with production losses and increase in crop prices higher food dependency on foreign imports and gdp losses in all the simulations after 2025 in a second part of the paper a cost effectiveness analysis of adaptation in nigerian agriculture is conducted the adaptation practices considered are a mix of cheaper soft measures and more costly hard irrigation expansion the main result is that the cost effectiveness of the whole package depends crucially on the possibility of implementing adaptation by exploiting low cost opportunities which show a benefit cost ratio larger than one in all the climate regimes

the calculation of returns to research in distorted markets reply abstract most of the emperical literature calculating rates of return to publicly sponsored research assumes that research is the only relevant government intervention for most countries this assumption is untenable this paper shows that improperly measuring government inducedmarket distortions can severely bias research rate of return calculations if the interaction between successful research and other government interventions increases the cost of the other interventions then neglecting market distortions unambigously increases the calculated rate of return three examples of government induced distortions show that the magnitude of the upward bias in calculated rates of return can be extremely large in some cases more than 100 percentage points a normative implication is that governments should account for interactions between research and price interventions when determining research support levels a positive implication is that existing government research funding patterns are more readily explainable as reasonable behavior by a government that accounts for these interactions

genetic improvements in major us crops the size and distribution of benefits the distribution of welfare gains of genetic improvements in major us crops is estimated using a world agricultural trade model multi market welfare estimates were 75 larger than estimates based on the price exogenous change in revenue method frequently used by plant breeders annual benefits of these genetic improvements range from us 400 600 million depending on the supply shift specification of this 44 60 accrues to the us 24 34 accrues to other developed countries developing and transitional economies capture 16 22 of the welfare gain the global benefits of a one time permanent increase in us yields are us 8 1 billion discounted at 10 and us 15 4 billion discounted at 5 gains to consumers in developing and transitional economies range from us 6 1 billion 10 discount rate to us 11 6 billion 5 discount rate

the distribution of benefits from technical change among classes of consumers and producers an ex anteanalysis of beans in brazil abstract because new agricultural technology in developing countries has sometimes bypassed small farmers who are an important social group in low income countries design of technology specifically appropriate to small farmers has been advocated as a policy goal this paper appraises the comparative returns to investment in small farm biased scale neutral and large farm biased technology for bean production in brazil a consumer surplus model is developed to estimate the distribution of benefits among producing sectors and classes of consumers while previous studies have relied on geometrical approximations to measure economic benefits as the area under the supply shifts here an exact analytic solution is obtained by integrating from the supply axis scale neutral technology leads to significant small farmer benefits while maximizing benefits to consumers large farm biased technology results in less benefits to small farmers and consumers and only minor gains to large farmers when compared to scale neutral technology small farm biased technology produces the greatest gains to small farmers but the lowest level of benefits to consumers