Niedertscheider Maria, Erb Karlheinz
Institute of Social Ecology, Vienna, Alpen-Adria Universität, Schottenfeldgasse 29, 1070 Vienna, Austria.
Land use policy. 2014 Jul;39:366-375. doi: 10.1016/j.landusepol.2014.01.015.
Over the past centuries, land systems in Italy experienced fundamental shifts, owing to the availability of new energy forms, population surges, and technological progress. The 20th century was characterized by massive productivity increases, accompanied by gradual land abandonment and the return of forest land. We here analyze 120 years of land system change in Italy, applying the human appropriation of net primary production (HANPP) framework, a metric for socio-economic pressures on terrestrial ecosystems. HANPP allows integrating ecological with societal perspectives, by systematically quantifying (a) biomass harvest and (b) the difference between potential productivity of ecosystems and current productivity induced by land use processes, such as land conversion, or land degradation. Besides assessing national trends we calculated HANPP separately for the Italian North and South between 1934 and 2007, in order to scrutinize if high regional discrepancies in terms of natural and socio-economic preconditions translate into diverging land system trajectories. Our results show that national HANPP has been declining from 78% of natural productivity before WWII to 56% in 2007, indicating a declining land -use induced pressure on biomass flows over time. Simultaneously, biomass harvest increased by around 26% due to agricultural intensification, despite shrinking croplands. Although we found a significant difference between the Northern and Southern region in the absolute levels of several land use indicators related to biomass appropriation, the overarching trends of land system change were remarkably similar in both regions. This suggests that underlying drivers of land system change, such as policies aimed at land-use intensification and structural change were equally dominating land system trajectories in the North and South of Italy, not withstanding their socio-ecological divergences.
在过去几个世纪里，由于新能源形式的出现、人口激增和技术进步，意大利的土地系统经历了根本性的转变。20世纪的特点是生产力大幅提高，同时伴随着土地逐渐被弃用和林地的回归。我们在此运用人类对净初级生产的占用（HANPP）框架，即一种衡量陆地生态系统所承受社会经济压力的指标，来分析意大利120年的土地系统变化。HANPP通过系统地量化（a）生物量收获以及（b）生态系统潜在生产力与土地利用过程（如土地转换或土地退化）所导致的当前生产力之间的差异，从而将生态视角与社会视角结合起来。除了评估全国趋势外，我们还分别计算了1934年至2007年意大利北部和南部的HANPP，以审视自然和社会经济前提条件方面的高度区域差异是否会转化为不同的土地系统轨迹。我们的研究结果表明，全国HANPP已从二战前占自然生产力的78%降至2007年的56%，这表明随着时间的推移，土地利用对生物量流动的压力在下降。与此同时，尽管耕地面积减少，但由于农业集约化，生物量收获增加了约26%。尽管我们发现与生物量占用相关的几个土地利用指标在北部和南部地区的绝对水平上存在显著差异，但两个地区土地系统变化的总体趋势非常相似。这表明，土地系统变化的潜在驱动因素，如旨在加强土地利用和结构调整的政策，在意大利北部和南部同样主导着土地系统轨迹，尽管它们在社会生态方面存在差异。
