CONTEXT: Livestock farming is a major factor in the balance or disruption of bio-geochemical cycles, climate and biodiversity. The Brazilian Amazon is emblematic of these tensions between livestock production and environment. Extensive cattle production has spearheaded the territorial conquest of this region for more than 50 years, and is the main cause of deforestation. The intensification of animal production is presented as a success factor for long-term maintenance of low deforestation and a good level of production. Yet in reality there is no guarantee of this outcome, and very few studies focus on quantifying the effective intensification of the Amazonian livestock sector, and its impact on deforestation.

OBJECTIVE: The objective of our article is to characterize and discuss the evolution of livestock farming in Paragominas (Brazil). This municipality is presented as an example of sustainable agrarian transition in the Amazon. After several decades with one of the highest rates of Amazon deforestation, Paragominas reduced its annual deforestation rate tenfold between 2005 and 2012.

METRHODS: We analyse the livestock sector, using the method of territorial metabolism. The first step consisted in making an inventory of all material flows and all areas used either directly or indirectly by livestock farming. We calculate productive and environmental indicators' trends from 1990 to 2012 (intensity, production, efficiency, self-sufficiency, deforestation and N surplus).

RESULTS AND CONCLUSIONS: We observe an extensive farming system with low density (between 0.47 and 0.83 LU/ha), low production (between 0.97 and 1.48 kg N/ha/year), low efficiency, but a large degree of self-sufficiency (exceeding 95%), and very low N surplus per hectare (between 14 and 16 kg N/ha/year). Ruminants account for 98% of all Livestock Units (LU) and over 95% of animal production. The selected indicators to characterize the intensity of farming systems are divergent: indicators expressed per unit area show extensification, with a decrease in animal density, inputs per ha and a stabilization of production per ha. However, production per animal unit and livestock efficiency increase across the study period.

SIGNIFICANCE: The increase in animal production and efficiency was not related to the decrease in deforestation. The increased oversight of land use, along with strict policies, enabled the cessation of deforestation, but this did not result in the intensification of livestock farming for the moment. Our study shows that there is significant potential to increase livestock production and efficiency.

背景：畜牧业是生物地球化学循环，气候和生物多样性平衡或破坏的主要因素。巴西亚马逊河象征着畜牧生产和环境之间的这些紧张关系。超过50年以来，广泛的牛畜生产带动了该地区的领土征服，是造成森林砍伐的主要原因。畜牧业生产的集约化是长期维持低森林砍伐和良好生产水平的成功因素。然而，实际上并不能保证这一结果，很少有研究专注于量化亚马逊地区畜牧业的有效集约化及其对森林砍伐的影响。

目的：本文的目的是描述和讨论巴拉戈米纳斯（巴西）畜牧业的演变。该自治市是亚马逊地区可持续农业转型的一个例子。在亚马逊森林砍伐率最高的几十年之后，帕拉戈米纳斯州将其每年的森林砍伐率在2005年至2012年期间降低了十倍。

方法：我们使用地域新陈代谢方法分析了畜牧业。第一步包括盘点所有物质流以及畜牧业直接或间接使用的所有区域。我们计算了1990年至2012年生产和环境指标的趋势（强度，产量，效率，自给自足，森林砍伐和氮过剩）。

结果与结论：我们观察到广泛的耕作制度，密度低（0.47至0.83 LU / ha /公顷），产量低（0.97至1.48 kg N / ha /年），效率低，但自给程度高（超过95％），每公顷的氮过剩非常低（14/16千克氮/公顷/年）。反刍动物占所有牲畜单位（LU）的98％，占动物产量的95％以上。所选的表征耕作制度集约化的指标是不同的：单位面积表示的指标显示出扩大化的趋势，其中动物密度，每公顷投入品和每公顷产量稳定。但是，在整个研究期间，每头动物的单位产量和牲畜效率提高。

意义：动物生产和效率的提高与森林砍伐的减少没有关系。加强对土地使用的监督，加上严格的政策，使森林砍伐得以停止，但这并没有导致目前畜牧业的集约化。我们的研究表明，提高牲畜产量和效率具有巨大潜力。