作者:夏梦丽,安徽大学经济学院;许文立,安徽大学经济学院
Nash(1972)认为“环境史”是当时的新兴领域,它将生态学和地理学纳入了对历史的解释中。为了研究“人类文化和以往环境的交互作用”(Worster,1988),早期的环境史学家遵循了Turner(1921)和Webb(1931)的开创性工作,撰写了西方国家的经验。Nash(1967)研究了美国人对于荒野的看法(译者注:《荒野与美国精神》美国环境史上第一部真正的思想方面的专著),而Hays(1959)主要关注美国的环境保护运动。随着该领域的发展,全球的文献都在阐述世界各地的人类和环境之间的相互作用和动态关系,如非洲((Beinart 1984, Fairhead and Leach 1996, Harms 1999)、亚洲(Elvin 2008, Gadgil and Guha 1993)、以及全球性视角(Crosby 1972)。
十几年来,经济学家已经对该领域做了许多贡献,但他们所使用的技术方法通常与环境史学家不同,且他们更强调自己研究的差异。环境经济学文献的关键贡献在于从一个十分宽泛、复杂的环境系统(包括知识、资本和制度)中,分离出特定的因果关系(Hornbeck 2012a),)它们通常还涉及新的GIS数据库的生成和使用。经济学文献所考虑的环境因素十分广泛,包括但不仅限于污染、风力等级、自然灾害、土壤质量、地形和病菌环境。因此,本文对环境经济史的简要概述将集中于环境对人类当前以及长期造成的影响,而不是关注于人类对环境的改造,尽管后者也是环境经济学文章所关注的重点问题(e.g. Hansen and Libecap 2004, Hornbeck and Keskin 2014, Taylor 2011)。正如本文下面的讨论,环境因素对发展有着深远的影响,这些影响包括直接环境影响,如农业禀赋或变化可能是制度、规范和社会发展演变的机制。另外一些环境因素如疾病负担有着类似的影响。本文尤其关注两个主题:地理禀赋和环境冲击对历史长期发展的影响。环境经济史的这两个方面与广泛的经济史文献紧密相关,这里的经济史文献主要是指那些研究历史事件对长期发展产生影响的文献(参见Nunn 2014的综述)
地理禀赋的影响
环境经济史文献的一个主要分支就是考察那些具有时间不变或变化缓慢的环境特征对经济产生的直接效应。这与长期经济增长中地理因素的作用有重叠的地方(e.g. Andersen et al. 2016, and Galor and Özak 2016)。例如,经济学家曾经写过疾病对过去家经济社会发展的影响,以及环境如何塑造了历史制度。Bleakley (2007) 研究了美国20世纪早期消除十二指肠胃病所导致的高感染区与低感染区的趋同现象,测度了病菌对教育的影响效应。他的实证方法也被用于评估其他疾病的经济社会效应(e.g. Lucas 2010, Cutler et al. 2010)。
关于地理禀赋对制度影响的研究,Fenske (2014)和Depetris-Chauvin (2015)都将沦为殖民地前的非洲国家的集权制度与源于生态多样性贸易的收益联系在一起。同样, Fenske (2013)记录了许多地理驱动因素,这些因素被用来预测全球跨地区的土地权、奴隶和人口密度。这些研究将非洲大陆的制度变迁相关的空间数据与环境GIS地图相结合,基于工具变量和可比较的国家观测值来进行相应的因果推断。从微观层面来看,Bubb(2013)发现在科特迪瓦和加纳,乔木种植的外在适应性条件是土地产权制度的更好解释变量,而不是殖民制度。类似地,包含土壤特征及其变化的GIS数据库已经被用于研究文化模式的历史起源,比如女性劳动力的参与(Alesina et al. 2013)、种族多样性(Michalopoulos 2012)以及伊斯兰教的传播(Michalopoulos et al. 2016)。
相反,其他一些地理禀赋效应的研究关注于影响当前经济社会状况的地理禀赋的间接长期效应,因为这些因素会影响历史进程。在一篇开创性的研究中,Alsan(2014)认为采采蝇大大降低了非洲目前的繁荣,主要是因为它抑制了前殖民地的政治集权[1]。为此,Alsan构造了GIS采采蝇适应性指数,并将其与现有的非洲族群地、前殖民制度和modern luminosity等数据合并。其研究结果表明,经过一系列的协变量调整、样本比较以及安慰剂检验之后,那些不存在采采蝇的地区不存在类似的效应。Fiszbein(2016)使用影响农业多样性收益的气候条件外生变动来研究农作物多样性对美国长期产业发展的影响。
类似地,Nunn(2014)强调了环境在影响特定历史事件和进程中的作用,而这些事件本身也有长期影响。非洲的奴隶贸易就是一个例子:最近的研究表明地形坚固(Nunn and Puga 2012)和地理隔离(Nunn,2008)影响了奴隶贸易的动态,并通过这些因素影响了非洲的发展。这些研究利用非洲大陆的地理和历史气候的GIS数据,并将地理编码与现存的奴隶贸易数据相结合,并从工具变量和安慰剂检验中进行因果推断。对非洲奴隶贸易的长期影响研究已经转向了那些具有相同地理条件的地区,以隔离奴隶出口的外生变动(e.g. Nunn and Wantchekon 2011, Dalton and Leung 2014)。
环境冲击的影响
鉴于诸如天气波动、自然灾害等环境事件中随时间变化的环境事件的重要性,以及基于源自外生变化的可信因果推断,一些研究评估了环境冲击对经济史的重要性。一些文章检验了如干旱、洪水、新疾病的传播对经济的直接影响,其中大多数都研究美国。例如,Davis等(2009)使用19世纪天气引起的棉花产量的变动来推断对非农业经济周期的因果效应;更大的棉花出口增加了高能货币的供给。类似地,Fishback等(2011)研究了大萧条时期气候或者天气是否影响死亡率。其他一些文献也检验了世界其他地区相似冲击的影响:例如 Fenske 、Kala (2015) 和 Rönnbäck (2014)都检验了大西洋奴隶贸易中温度波动的作用,结果发现这些因素影响了非洲市场奴隶贸易参与的程度和价格。
历史背景下的冲突和政治转型事件以及他们对历史进程的重要性可以相对容易的记录,已经有大量的研究关注于此。Hsiang等(2013)提供了大量的参考文献,其中包括了许多历史案例。Christia、Fenske (2015) ,Papaioannou 和de Haas (2015)将殖民时期非洲的不利天气分别与动乱和犯罪联系起来。关于中国的研究, Jia(2014)和Bai and Kung(2011)也使用天气变化来解释历史上的暴动事件。Chaney(2013)发现尼罗河洪水泛滥时期降低了穆斯林埃及最高等级宗教机构被取代的可能性。这些研究从档案资料或历史重建中获取历史天气数据,并将它们与冲突和政治转型相关的资料相结合,以产生覆盖环境经济史的历史数据集。
其他一些研究通过将环境灾难所影响到的地区、个体与没有发生环境灾难的那些对照组进行比较,刻画了环境灾难的长期效应。通过对土壤侵蚀地图进行地理编码,Cutler等(2007) 和Arthi (2014)等作者研究了美国尘暴时代对个人健康的长期影响,而Hornbeck (2012b)研究了土壤侵蚀对土地价值、人口和农作物发展的影响。干旱对墨西哥革命(Dell 2012)、棉铃象鼻虫的传播(Lange等,2009)以及密西西比河大洪水(Hornbeck和naidu2014)的长期影响也都有类似的研究。研究结果已经表明这些影响持续到现在,因此,上述研究显示了环境史对于理解现代发展的意义。
结论
环境史现在已然是一个成熟的研究领域,并且作为经济史分支的环境经济史也得到了较好的发展,但是这些文献的整合还不够理想。我们希望来源于环境经济史研究的结论、数据资源和方法可以进一步丰富环境史的作品。而且,环境史文献中还有许多重要主题没有受到经济学家的足够关注,如中国朝代更迭与环境之间的动态关系(Elvin 2008)、殖民地森林保护的福利效应(Gadgil and Guha 1993)以及殖民地土地保护的政治经济学(Mackenzie 1998)。自然环境在社会发展中起到了十分重要的作用,而其中的传导机制往往是对制度产生了影响。我们期待看到一些新方法来研究该领域的重要问题。
References
Alesina, A, P Giuliano and N Nunn (2013), “On the Origins of Gender Roles: Women and the Plough”, The Quarterly Journal of Economics, 128(2), 469-530
Alsan, M (2014), “The effect of the tsetse fly on African development”, The American Economic Review, 105(1), 382-410.
Andersen, T B, C J Dalgaard, and P Selaya (2016), “Climate and the Emergence of Global Income Differences”, The Review of Economic Studies, 83 (4): 1334-1363
Arthi, V (2014), “‘The Dust Was Long in Settling’: Human Capital and the Lasting Impact of the American Dust Bowl”, University of Oxford Discussion Papers in Economic and Social History #129
Bai, Y and J K S Kung (2011), “Climate shocks and Sino-nomadic conflict”, Review of Economics and Statistics, 93(3), 970-981
Beinart, W (1984), “Soil erosion, conservationism and ideas about development: a southern African exploration, 1900–1960”, Journal of Southern African Studies, 11(1), 52-83.
Bleakley, H (2007), “Disease and development: evidence from hookworm eradication in the American South”, The Quarterly Journal of Economics, 122(1), 73-117.
Bubb, R (2013), “The evolution of property rights: State law or informal norms?” Journal of Law and Economics, 56(3), 555-594.
Chaney, E (2013), “Revolt on the Nile: Economic shocks, religion, and political power”, Econometrica, 81(5), 2033-2053.
Christian, C and J Fenske (2015), Economic shocks and unrest in French West Africa. Centre for the Study of African Economies Working Paper 2015-01.
Crosby, A W (1972), The Columbian Exchange: Biological and Social Consequences of 1492, Greenwood Press
Cutler, D, W Fung, M Kremer, M Singhal, and T Vogl (2010), “Early-life malaria exposure and adult outcomes: Evidence from malaria eradication in India”, American Economic Journal: Applied Economics, 2(2), 72-94.
Cutler, D M, G Miller and D M Norton (2007), “Evidence on early-life income and late-life health from America’s Dust Bowl era”, Proceedings of the National Academy of Sciences, 104(33), 13244-13249.
Dalton, J T and T C Leung (2014), “Why is polygyny more prevalent in Western Africa? An African slave trade perspective”, Economic Development and Cultural Change, 62(4), 599-632.
Davis, J H, C Hanes, and P W Rhode (2009), “Harvests and Business Cycles in Nineteenth-Century America”, The Quarterly Journal of Economics, 1675-1727.
Depetris-Chauvin, E (2015), “State history and contemporary conflict: Evidence from Sub-Saharan Africa”, Working Paper, Pontificia Universidad Catolica de Chile.
Dell, M (2012), Path Dependence in Development: Evidence from the Mexican Revolution, Working Paper, Harvard University.
Elvin, M (2008), The retreat of the elephants: an environmental history of China, Yale University Press.
Fairhead, J, and M Leach (1996), Misreading the African landscape: society and ecology in a forest-savanna mosaic. Cambridge University Press.
Fenske, J (2013), “Does land abundance explain African institutions?”, The Economic Journal, 123(573), 1363-1390.
Fenske, J and N Kala (2015), “Climate and the slave trade”, Journal of Development Economics, 112, 19-32.
Fenske, J (2014), “Ecology, trade, and states in pre‐colonial Africa”, Journal of the European Economic Association, 12(3), 612-640.
Fishback, P V , W Troesken, T Kollmann, M Haines, P W Rhode, and M Thomasson (2011), “Information and the impact of climate and weather on mortality rates during the Great Depression”, In The Economics of Climate Change: Adaptations Past and Present (pp. 131-167), University of Chicago Press.
Fiszbein, M (2015), Agricultural Diversity, Structural Change and Long-run Development: Evidence from US Counties. https://goo.gl/aIEFI8
Gadgil, M and R Guha (1993), This fissured land: an ecological history of India, University of California Press.
Galor, O and O Özak (2016), “The Agricultural Origins of Time Preference”, American Economic Review, 106(10):3064–3103.
Hansen, Z K and G D Libecap (2004), “Small Farms, Externalities, and the Dust Bowl of the 1930s”, Journal of Political Economy, 112(3), 665-694.
Harms, R (1999), Games against nature: an eco-cultural history of the Nunu of equatorial Africa, Cambridge University Press.
Hays, S (1959), Conservation and the Gospel of Efficiency: The Progressive Conservation Movement 1890-1920, Harvard University Press
Hornbeck, R (2012a). “The Republic of Nature: An Environmental History of the United States. By Mark Fiege. Seattle: University of Washington Press, 2012. Pp. xii, 584. $34.95, hardcover.” (review) The Journal of Economic History, 72(04), 1120-1121.
Hornbeck, R (2012b) “The enduring impact of the American Dust Bowl: Short-and long-run adjustments to environmental catastrophe”, The American Economic Review, 102(4), 1477-1507.
Hornbeck, R and P Keskin (2014), “The historically evolving impact of the ogallala aquifer: Agricultural adaptation to groundwater and drought”, American Economic Journal: Applied Economics, 6(1), 190-219.
Hornbeck, R and S Naidu (2014), “When the levee breaks: black migration and economic development in the American South”, The American Economic Review, 104(3), 963-990.
Hsiang, S M, M Burke, and E Miguel (2013), “Quantifying the influence of climate on human conflict”, Science, 341(6151), 1235367.
Jia, R (2014), “Weather shocks, sweet potatoes and peasant revolts in historical China”, The Economic Journal, 124(575), 92-118.
Lange, F, A L Olmstead and P W Rhode (2009), “The Impact of the Boll Weevil, 1892– 1932”, The Journal of Economic History, 69(03), 685-718.
Lucas, A M (2010), “Malaria eradication and educational attainment: evidence from Paraguay and Sri Lanka”, American Economic Journal: Applied Economics, 2(2), 46-71.
Mackenzie, A F D (1998), Land, ecology and resistance in Kenya, 1880-1952, Edinburgh University Press.
Michalopoulos, S (2012), “The origins of ethnolinguistic diversity”, The American Economic Review, 102(4), 1508-1539.
Michalopoulos, S, A Naghavi, and G Prarolo (2016), “Islam, inequality and pre- industrial comparative development”, Journal of Development Economics, 120, 86-98.
Nash, R (1967), Wilderness and the American Mind, Yale University Press.
Nash, R (1972), “American Environmental History: A New Teaching Frontier”, Pacific Historical Review, 41 (3): 362–372.
Nunn, N (2014), “Historical development”, Handbook of Economic Growth, 2, 347-402.
Nunn, N and D Puga (2012), “Ruggedness: The blessing of bad geography in Africa”, Review of Economics and Statistics, 94(1), 20-36.
Nunn, N (2008), “The Long-term Effects of Africa’s Slave Trades”, The Quarterly Journal of Economics, 123(1), 139-176.
Nunn, N and L Wantchekon (2011), “The slave trade and the origins of mistrust in Africa”, The American Economic Review, 101(7), 3221-3252.
Papaioannou, K J and M de Haas (2015), Climate Shocks, Cash Crops and Resilience: Evidence from colonial tropical Africa, University of Wageningen Working Paper.
Rönnbäck, K (2014), “Climate, conflicts, and variations in prices on pre‐colonial West African markets for staple crops”, The Economic History Review, 67(4), 1065-1088.
Taylor, S M (2011), “Buffalo hunt: International trade and the virtual extinction of the North American bison”, The American Economic Review, 101(7), 3162-3195.
Turner, F J (1921), The Frontier in American History, Henry Holt and Company.
Webb, W P (1931), The Great Plains: a study in institutions and environment, Ginn and Co.
Worster, D (1988), The ends of the earth: perspectives on modern environmental history, Cambridge University Press.