Reconstructing crop yield variability in Finland: Long-term perspective of the cultivation history on the agricultural periphery since ad 760
Reconstructing crop yield variability in Finland: Long-term perspective of the cultivation history on the agricultural periphery since ad 760
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重建芬兰作物产量的变异性：自公元 760 年以来农业周边地区耕作历史的长期视角
DOI：
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发表时间：
2017
期刊：
影响因子：
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通讯作者：
S. Helama
中科院分区：
文献类型：
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作者：
Heli Huhtamaa;S. Helama
缺乏关于以往收成波动的文件，限制了对作物生产和农业适应战略长期趋势的探讨。然而，要了解人类对环境和气候变化可能作出的广泛反应，需要有一个长期的视角。因此，我们使用树轮密度系列作为代理数据，以重建气候介导的产量比（收获的粮食播种）在中部和北方芬兰在公元760 - 2000年期间。重建解释了50%的方差在校准期间（公元1866年至1921年）记录的产量比的变化。重建表明，在过去的13个世纪中，产量比增加和减少的几个间隔。农业条件的长期发展的特点是不同的时间段，统计定义为公元760 - 1106年（最高产量比），1107 - 1451年，1452 - 1694年，1695 - 1911年（最低产量比）和1912年以后。研究结果为农业边缘区作物种植业的建立和发展提供了参考。重建表明，连续作物种植建立在研究区域的气候条件支持高产的有利时期。此后，气候介导的收益率在长期内下降，直到世纪之交。农业转型时期，那些以前在花粉数据和历史文献中证明，我们的重建表明，低产量比阶段的开始。因此，我们认为，自农作物种植建立以来，气候可以被认为是促进北方农业历史发展的重要因素。
Lack of documentation on past harvest fluctuations limits the exploration of long-term trends in crop production and agricultural adaptation strategies. A long-term perspective is needed, however, to understand the wide spectrum of potential human responses to environment and climate change. Therefore, we used tree-ring density series as proxy data to reconstruct climate-mediated yield ratio (harvested grain in relation to sown) in central and northern Finland over the period ad 760–2000. The reconstruction explains 50% of the variance in recorded yield ratio variability over the calibration period (ad 1866–1921). The reconstruction illustrated several intervals of increased and reduced yield ratio over the past 13 centuries. The long-term development of the agricultural prerequisites is characterized by distinct intervals defined statistically as ad 760–1106 (highest yield ratios), 1107–1451, 1452–1694, 1695–1911 (lowest yield ratios) and 1912 onwards. The results provide insight into the establishment and development of crop cultivation in the agricultural margin. The reconstruction suggests that continuous crop cultivation was established in the study region during a favourable period of climatic conditions supporting high yields. Thereafter, the climate-mediated yield ratio declined in the long run until the turn of the 20th century. Periods of agricultural transformations, those previously demonstrated in pollen data and historical documents, followed the onsets of the low yield ratio phases indicated by our reconstruction. Thus, we suggest that ever since the establishment of crop cultivation, climate can be considered as an important factor contributing to the development of the agricultural history in the north.