The Effects of Climate and Population Density on Agricultural Production

气候和人口密度对农业生产的影响

• 批准号: 1749059
• 负责人: Joan Coltrain
• 金额: $ 21.59万
• 依托单位: University of Utah
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-03-01 至 2021-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1749059&HistoricalAwards=false
• 关键词: Effects; Climate; Population; Density; Agricultural

The transition to food production represents one of the most significant events in human history. Growing evidence for the persistence of agriculture through periods of population collapse and environmental change suggests that the transition to food production is a tipping point from which human populations cannot return, but at least one case study provides evidence to the contrary. The Fremont in the Basin-Plateau region of Western North America farmed maize for nearly a millennium, from about 1550-650 years ago (AD 450-1350), then abandoned agriculture and their farming villages a few centuries prior to European contact. Farming ceased earlier in some regions of the Fremont landscape than in others but by AD 1350 most of the characteristics of settlement pattern that identified the Fremont as an archaeological complex were no longer present. At European contact groups living in the eastern Great Basin and on the northern Colorado Plateau had returned to mobile hunting and gathering. Reasons for both the origin and demise of Fremont farming have been hotly debated, but a consensus is lacking. This project will generate extensive data on diet, climate and demography in order to address the rise, spatiotemporal variation in reliance on maize and fall of the Fremont complex, which will serve as a model system to explore the dynamics that lead to agricultural collapse. Several approaches will be used to reconstruct the variables that likely determined the investment of Fremont populations in maize agriculture and their decision to return to foraging. Demography - the size and distribution of human populations - is one critical factor. Summed radiocarbon dates from Fremont contexts will be used as a proxy for prehistoric population densities. Research has shown population growth puts pressure on wild resources and can be a driver of reliance on domesticates. Thus, variation in the size and structure of local Fremont populations may address variation in reliance on maize. Modeling agricultural suitability will further inform this work. Key climatic variables that affect maize productivity such as precipitation, growing degree days, soil moisture and soil chemistry are critical to the success of maize farming. Modern data will be temporally adjusted with tree-ring chronologies to reconstruct paleo-climate across the Fremont region. Finally the bone chemistry of a large collection of Fremont individuals will be analyzed to determine spatiotemporal variation in the dietary importance of maize. Once all the data are assembled the relative influence of each factor will be evaluated. The resulting analyses will examine how an individual's reliance on maize agriculture varied as a function of each explanatory variable while holding time, space and other confounds constant.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

向粮食生产的过渡是人类历史上最重要的事件之一。越来越多的证据表明，农业在人口崩溃和环境变化期间持续存在，这表明向粮食生产的过渡是一个人口无法恢复的转折点，但至少有一个案例研究提供了相反的证据。在北美西部盆地高原地区的弗里蒙特种植玉米近一千年，从大约1550-650年前（公元450-1350年），然后放弃农业和他们的农业村庄几个世纪前欧洲接触。在弗里蒙特的某些地区，农业停止得比其他地区更早，但到公元1350年，弗里蒙特作为一个考古综合体的定居模式的大部分特征已经不复存在。 居住在大盆地东部和科罗拉多高原北方的欧洲接触群体已经恢复了移动的狩猎和采集。弗里蒙特农业的起源和消亡的原因一直在激烈争论，但缺乏共识。该项目将产生关于饮食、气候和人口的广泛数据，以解决弗里蒙特综合体对玉米依赖的上升、时空变化和下降问题，该综合体将作为一个模型系统，探索导致农业崩溃的动态。几种方法将被用来重建的变量，可能决定投资的弗里蒙特人口在玉米农业和他们的决定返回觅食。人口统计学-人口的规模和分布-是一个关键因素。 弗里蒙特地区的放射性碳年代总和将被用作史前人口密度的代表。研究表明，人口增长给野生资源带来了压力，并可能成为依赖驯养动物的驱动力。因此，当地弗里蒙特人口的规模和结构的变化可能会解决依赖玉米的变化。农业适宜性建模将进一步为这项工作提供信息。影响玉米生产力的关键气候变量，如降水、生长度日、土壤水分和土壤化学，对玉米种植的成功至关重要。现代数据将与树木年轮年表在时间上进行调整，以重建整个弗里蒙特地区的古气候。最后，将分析大量弗里蒙特个体的骨化学，以确定玉米饮食重要性的时空变化。 一旦所有的数据被收集，每个因素的相对影响将被评估。由此产生的分析将研究如何一个人对玉米农业的依赖变化作为每个解释变量的函数，同时保持时间，空间和其他混淆常数。这个奖项反映了NSF的法定使命，并已被认为是值得通过使用基金会的智力价值和更广泛的影响审查标准进行评估的支持。

项目成果

Socioecological Dynamics Structuring the Spread of Farming in the North American Basin-Plateau Region

构建北美盆地高原地区农业传播的社会生态动力学

• DOI: 10.1080/14614103.2021.1927480
• 发表时间: 2021
• 期刊: Environmental Archaeology
• 影响因子: 1.5
• 作者: Codding, Brian F.;Brenner Coltrain, Joan;Louderback, Lisbeth;Vernon, Kenneth Blake;Magargal, Kate E.;Yaworsky, Peter M.;Robinson, Erick;Brewer, Simon C.;Spangler, Jerry D.
• 通讯作者: Spangler, Jerry D.

Legacies of Indigenous land use shaped past wildfire regimes in the Basin-Plateau Region, USA

原住民土地利用的遗产塑造了美国盆地高原地区过去的野火状况

• DOI: 10.1038/s43247-021-00137-3
• 发表时间: 2021
• 期刊: Communications Earth & Environment
• 影响因子: 7.9
• 作者: Carter, Vachel A.;Brunelle, Andrea;Power, Mitchell J.;DeRose, R. Justin;Bekker, Matthew F.;Hart, Isaac;Brewer, Simon;Spangler, Jerry;Robinson, Erick;Abbott, Mark
• 通讯作者: Abbott, Mark