Comprehensive assessment of carbon productivity, allocation and storage in three Amazonian forests

The allocation and cycling of carbon (C) within forests is an important component of the biospheric C cycle, but is particularly understudied within tropical forests. We synthesise reported and unpublished results from three lowland rainforest sites in Amazonia (in the regions of Manaus, Tapajós and Caxiuanã), all major sites of the Large‐Scale Biosphere–Atmosphere Programme (LBA). We attempt a comprehensive synthesis of the C stocks, nutrient status and, particularly, the allocation and internal C dynamics of all three sites. The calculated net primary productivities (NPP) are 10.1±1.4 Mg C ha⁻¹ yr⁻¹ (Manaus), 14.4±1.3 Mg C ha⁻¹ yr⁻¹ (Tapajós) and 10.0±1.2 Mg C ha⁻¹ yr⁻¹ (Caxiuanã). All errors bars report standard errors. Soil and leaf nutrient analyses indicate that Tapajós has significantly more plant‐available phosphorus and calcium. Autotrophic respiration at all three sites (14.9–21.4 Mg C ha yr⁻¹) is more challenging to measure, with the largest component and greatest source of uncertainty being leaf dark respiration. Comparison of measured soil respiration with that predicted from C cycling measurements provides an independent constraint. It shows general good agreement at all three sites, with perhaps some evidence for measured soil respiration being less than expected. Twenty to thirty percent of fixed C is allocated belowground. Comparison of gross primary productivity (GPP), derived from ecosystem flux measurements with that derived from component studies (NPP plus autotrophic respiration) provides an additional crosscheck. The two approaches are in good agreement, giving increased confidence in both approaches to estimating GPP. The ecosystem carbon‐use efficiency (CUEs), the ratio of NPP to GPP, is similar at Manaus (0.34±0.10) and Caxiuanã (0.32±0.07), but may be higher at Tapajós (0.49±0.16), although the difference is not significant. Old growth or infertile tropical forests may have low CUE compared with recently disturbed and/or fertile forests.     

Le genre Anomalocornis Carvalho & Wygodzinsky 1945 (Heteroptera: Miridae: Phylinae), revision taxonomique,description d’une espèce nouvelle et affinités avec les palmiers néotropicaux

Le genre néotropical Anomalocornis Carvalho & Wygodzinsky 1945, est révisé. Les espèces A. geijskesi Carvalho & Wygodzinsky 1945, A. ariasi Carvalho 1982, A. tucuruiensis Carvalho 1984, A. rondoniensis Carvalho 1984, A. couturieri Carvalho & Costa 1993 and A. peyreti Couturier & Costa 2002 sont redécrites, leurs femelles, ainsi qu’une nouvelle espèce de Colombie, A. gentyi n. sp. sont décrites. Les espèces se différencient entre elles par leur taille, la coloration du corps, la morphologie et la coloration des articles I et II de l’antenne du mâle et par la structure des génitalia. Les différentes espèces sont originaires du Brésil, de Colombie, de l’Equateur, du Pérou et du Surinam. Toutes les espèces, excepté A. ariasi, dont la plante-hôte n’est pas connue, vivent sur les inflorescences de palmiers.     

Post-Boom Logging in Amazonia

Recent analyses of timber exploitation in Amazonia conclude that a variety of socioeconomic and ecological factors in the region make a stable and profitable logging industry virtually impossible. Most of these studies focus on large-scale timber industries and their dependence on over-exploitation of a small number of high-value timbers. In this article we discuss the economic, ecological, and social aspects of Amazonian logging in a region where the timber industry appeared to have collapsed after stocks of high-value timber were exhausted. We show that forestry in a post-boom phase, currently found in many areas of Amazonia, differs from the better-described boom period in its scale of operations, in the range of timbers cut, in management practices employed, and in the costs and benefits of production. Results of a seven-year study show that when sawtimber, poles and firewood are produced in a management system that combines forestry and agriculture they can provide significant additional income for Amazonian smallholders.     

小煤炱科二个新种

报道了中国小煤炱科Meliolaceae2个新种。它们是南蛇藤双孢炱负AmazoniacelastriY．X．HuetB．Songsp．nov．和乌桕生小煤炱MeliolasapiicolaY.X.HuetB.Songsp.nov.。模式标本存放在广东省微生物研究所（GDIM）。     

Amazonia and the modern carbon cycle: lessons learned

In this paper, we review some critical issues regarding carbon cycling in Amazonia, as revealed by several studies conducted in the Large Scale Biosphere Atmosphere Experiment in Amazonia (LBA). We evaluate both the contribution of this magnificent biome for the global net primary productivity/net ecosystem exchange (NPP/NEE) and the feedbacks of climate change on the dynamics of Amazonia. In order to place Amazonia in a global perspective and make the carbon flux obtained through the LBA project comparable with global carbon budgets, we extrapolated NPP/NEE values found by LBA studies to the entire area of the Brazilian Amazon covered by rainforest. The carbon emissions due to land use changes for the tropical regions of the world produced values from 0.96 to 2.4 Pg C year⁻¹, while atmospheric CO₂ inversion models have recently indicated that tropical lands in the Americas could be exchanging a net 0.62±1.15 Pg C year⁻¹ with the atmosphere. The difference calculated from these two methods would imply a local sink of approximately 1.6–1.7 Pg C year⁻¹, or a source of 0.85 ton C ha⁻¹ year⁻¹. Using our crude extrapolation of LBA values for the Amazon forests (5 million km²) we estimate a range for the C flux in the region of −3.0 to 0.75 Pg C year⁻¹. The exercise here does not account for environmental variability across the region, but it is an important driver for present and future studies linking local process (i.e. nutrient availability, photosynthetic capacity, and so forth) to global and regional dynamic approaches.     

Projecting future fire activity in Amazonia

Fires are major disturbances for ecosystems in Amazonia. They affect vegetation succession, alter nutrients and carbon cycling, and modify the composition of the atmosphere. Fires in this region are strongly related to land‐use, land‐cover and climate conditions. Because these factors are all expected to change in the future, it is reasonable to expect that fire activity will also change. Models are needed to quantitatively estimate the magnitude of these potential changes. Here we present a new fire model developed by relating satellite information on fires to corresponding statistics on climate, land‐use and land‐cover. The model is first shown to reproduce the main contemporary large‐scale features of fire patterns in Amazonia. To estimate potential changes in fire activity in the future, we then applied the model to two alternative scenarios of development of the region. We find that in both scenarios, substantial changes in the frequency and spatial patterns of fires are expected unless steps are taken to mitigate fire activity.     

The Death and Rebirth of Anthropology

This paper is a study of one component of the recent and contemporary circulation of cultural objects, the exhibition of Australian Aboriginal acrylic paintings in a French museum. The author argues that the recent emphases on ‘appropriation ‘ and the primitivizing gaze ‘ are not sufficient to understand what happens when such objects circulate. To ask what does happen in circulation, at the sites of exhibition, is to ask how they are produced, inflected, and invoked in concrete institutional settings, which have distinctive histories, purposes, and structures of their own. The gazes’ (representations) which are discussed in this French example are analyzed within the specific conditions of their production to show how such exhibitions and circulations of culture are produced in relationship to the requirements internal to museums to distinguish themselves from others, to respond to claims placed upon them by their own institutional settings.