EVALUACIÓN DE LAS TÉCNICAS DE APROVECHAMIENTO DE FRUTOS DE AGUAJE (Mauritia Flexuosa L.f.) EN EL DISTRITO DE JENARO HERRERA, LORETO, PERÚ

The buriti is a palm of high commercial value, with ecological and social importance in the Peruvian Amazon. The excessive felling of the female individuals for the use of the fruits has caused that the fruit harvest is carried out at greater distances from the population centres and has triggered the degradation and low state of conservation of the natural palm swamps. The objective of this study was to evaluate how the inhabitants are adapting to the degradation of the resource, through the implementation of techniques of sustainable use of buriti fruits. We applied semi-structured surveys to 35 aguaje harvesters, evaluated 17 harvesting areas and accompanied 8 harvesters in the use of the buriti fruits of 16 adult individuals. The results show that the inhabitants of the district of Jenaro Herrera have implemented harvesting techniques that prevent the death of female plants less than 20 meters height, that is, they make sustainable use of the resource. In addition, the cultivation of the species in the farms and orchards demonstrates the concern of the inhabitants to keep this resource closer to the population centres. These activities demonstrate the ability of local people to adapt to the scarcity of buriti fruits. Therefore, the willingness to manage the resource generates new opportunities for the conservation and sustainable management of the buriti, thus ensuring the supply of demand.El aguaje es una palmera de alto valor comercial con importancia ecológica y social en la Amazonía Peruana. La tala excesiva de los individuos femeninos para el aprovechamiento de los frutos ha generado que la cosecha se realice cada vez a mayor distancia de los centros poblados y ha desencadenado la degradación y bajo estado de conservación de los aguajales en bosques naturales. El presente estudio tuvo como objetivo evaluar cómo los pobladores se vienen adaptando a la degradación del recurso, a través de la implementación de técnicas de aprovechamiento sostenible de frutos de aguaje. Aplicamos encuestas semi-estructuradas a 35 cosechadores de aguaje, evaluamos 17 áreas de aprovechamiento y acompañamos a 8 cosechadores en el aprovechamiento de los frutos de aguaje de 16 individuos adultos. Los resultados muestran que los pobladores del distrito de Jenaro Herrera han implementado técnicas de aprovechamiento que evitan la muerte de las plantas femeninas de menos de 20 metros de altura, es decir, hacen uso sostenible del recurso. Asimismo, el cultivo de la especie en los predios y huertas demuestra la preocupación de los pobladores por mantener este recurso más cerca a los centros poblados. Estas actividades desarrolladas demuestran la capacidad de adaptación de los pobladores locales a la escasez del recurso aguaje. Por lo tanto, la voluntad de manejar el recurso genera nuevas oportunidades para la conservación y manejo sostenible del aguaje, asegurando así el abastecimiento de la demanda

Identifying and quantifying the abundance of economically important palms in tropical moist forest using UAV imagery

Sustainable management of non-timber forest products such as palm fruits is crucial for the long-term conservation of intact forest. A major limitation to expanding sustainable management of palms has been the need for precise information about the resources at scales of tens to hundreds of hectares, while typical ground-based surveys only sample small areas. In recent years, small unmanned aerial vehicles (UAVs) have become an important tool for mapping forest areas as they are cheap and easy to transport, and they provide high spatial resolution imagery of remote areas. We developed an object-based classification workflow for RGB UAV imagery which aims to identify and delineate palm tree crowns in the tropical rainforest by combining image processing and GIS functionalities using color and textural information in an integrative way to show one of the potential uses of UAVs in tropical forests. Ten permanent forest plots with 1170 reference palm trees were assessed from October to December 2017. The results indicate that palm tree crowns could be clearly identified and, in some cases, quantified following the workflow. The best results were obtained using the random forest classifier with an 85% overall accuracy and 0.82 kappa index.Publisher PDFPeer reviewe

Ficus insipida subsp. insipida (Moraceae) reveals the role of ecology in the phylogeography of widespread Neotropical rain forest tree species

Aim: To examine the phylogeography of Ficus insipida subsp. insipida in order to investigate patterns of spatial genetic structure across the Neotropics and within Amazonia. Location: Neotropics. Methods: Plastid DNA (trnH-psbA; 410 individuals from 54 populations) and nuclear ribosomal internal transcribed spacer (ITS; 85 individuals from 27 populations) sequences were sampled from Mexico to Bolivia, representing the full extent of the taxon's distribution. Divergence of plastid lineages was dated using a Bayesian coalescent approach. Genetic diversity was assessed with indices of haplotype and nucleotide diversities, and genetic structure was examined using spatial analysis of molecular variance (SAMOVA) and haplotype networks. Population expansion within Amazonia was tested using neutrality and mismatch distribution tests. Results: trnH-psbA sequences yielded 19 haplotypes restricted to either Mesoamerica or Amazonia; six haplotypes were found among ITS sequences. Diversification of the plastid DNA haplotypes began c. 14.6 Ma. Haplotype diversity for trnH-psbA was higher in Amazonia. Seven genetically differentiated SAMOVA groups were described for trnH-psbA, of which two were also supported by the presence of unique ITS sequences. Population expansion was suggested for both markers for the SAMOVA group that contains most Amazonian populations. Main conclusions: Our results show marked population genetic structure in F. insipida between Mesoamerica and Amazonia, implying that the Andes and seasonally dry areas of northern South America are eco-climatic barriers to its migration. This pattern is shared with other widespread pioneer species affiliated to wet habitats, indicating that the ecological characteristics of species may impact upon large-scale phylogeography. Ficus insipida also shows genetic structure in north-western Amazonia potentially related to pre-Pleistocene historical events. In contrast, evident population expansion elsewhere in Amazonia, in particular the presence of genetically uniform populations across the south-west, indicate recent colonization. Our findings are consistent with palaeoecological data that suggest recent post-glacial expansion of Amazonian forests in the south

The high hydraulic conductivity of three wooded tropical peat swamps in northeast Peru : measurements and implications for hydrological function

This research was supported by a NERC PhD studentship to the lead author, as well as by a Dudley Stamp Memorial Award from the Royal Geographical Society.The form and functioning of peatlands depend strongly on their hydrological status, but there are few data available on the hydraulic properties of tropical peatlands. In particular, the saturated hydraulic conductivity (K) has not previously been measured in neotropical peatlands. Piezometer slug tests were used to measure K at two depths (50 and 90 cm) in three contrasting forested peatlands in the Peruvian Amazon: Quistococha, San Jorge and Buena Vista. Measured K at 50 cm depth varies between 0.00032 and 0.11 cm s−1, and at 90 cm, it varies between 0.00027 and 0.057 cm s−1. Measurements of K taken from different areas of Quistococha showed that spatial heterogeneity accounts for ~20% of the within-site variance and that depth is a good predictor of K. However, K did not vary significantly with depth at Buena Vista and San Jorge. Statistical analysis showed that ~18% of the variance in the K data can be explained by between-site differences. Simulations using a simple hydrological model suggest that the relatively high K values could lead to lowering of the water table by >10 cm within ~48 m of the peatland edge for domed peatlands, if subjected to a drought lasting 30 days. However, under current climatic conditions, even with high K, peatlands would be unable to shed the large amount of water entering the system via rainfall through subsurface flow alone. We conclude that most of the water leaves these peatlands via overland flow and/or evapotranspiration.PostprintPeer reviewe

CARACTERIZACIÓN ESTRUCTURAL, PRODUCCIÓN Y FENOLOGÍA REPRODUCTIVA DE Mauritia flexuosa L.f. "aguaje" EN PLANTACIONES FORESTALES DE JENARO HERRERA, LORETO, PERÚ

In this study, we generated information on the structural characteristics and reproductive phenology of aguaje in six plantations from 11,6 to 17 years old established in the Jenaro Herrera Research Centre, Loreto, Peru. We observed and measured plant survival, structural characteristics, and phenology. The results showed that plant survival ranged from 66% to 96%. The majority of the variables did not show an increase with the age of the plantation, except for the mean stem height and total height, which were higher in the 17‑year‑old plantation than in the younger plantations. The reproductive stage of plants began at 6‑7 years with the flowering of a few individuals and showing an increase in the number of flowering plants in the plantations each year. The flowering and fruiting of aguaje plants occurred annually with synchrony in the flowering of male and female plants. However, some plants did not flower for periods of one to three years. The flowering period lasted on average 58,2 ± 0,9 days in the female plants and 55,1 ± 0,8 days in the male plants, while fruiting lasted 275,0 ± 1,6 days. The obtained information contributes to the silvicultural knowledge for the management of aguaje in plantations.En este estudio, generamos información sobre las caracterı́sticas estructurales y la fenologı́a reproductiva del aguaje en seis plantaciones de 11,6 a 17 años establecidas en el Centro de Investigaciones Jenaro Herrera, Loreto, Perú. Realizamos observaciones y mediciones de la supervivencia de las plantas, sus caracterı́sticas estructurales y la fenologı́a. Los resultados muestran que la supervivencia de las plantas desde el inicio de la plantación varió desde 66% hasta 96%. La mayorı́a de las variables evaluadas no mostraron incremento con la edad de la plantación, a excepción de la altura promedio del estı́pite y la altura total que fueron mayores en las plantaciones de 17 años que en las plantaciones menores. La etapa reproductiva inició a los 6‑7 años con la floración de pocos individuos, mostrando un aumento en el número de plantas en floración en todas las plantaciones cada año. La floración y fructificación ocurrió anualmente, con sincronı́a en la floración de las plantas femeninas y masculinas. Sin embargo, algunas plantas no florecieron durante periodos de 1 a 3 años. El perı́odo de floración duró en promedio 58,2 ± 0,9 dı́as en las plantas femeninas y 55,1 ± 0,8 dı́as en las masculinas, mientras que la fructificación duró 275,0 ± 1,6 dı́as. La información obtenida contribuye al conocimiento silvicultural para el manejo del aguaje en plantaciones

The vulnerability of tropical peatlands to oil and gas exploration and extraction

Funding: Leverhulme Trust (Grant Number(s): RPG-2018-306); UK Natural Environment Research Council (Grant Number(s): NE/R000751/1, NE/R016860/1, NE/V018760/1); Scottish Research Council/University of St Andrews.Tropical peatlands store globally significant quantities of carbon and are ecologically and culturally important, but little is known about their vulnerability to oil and gas exploration and extraction. Here, we analyse the exposure of tropical peatlands to the activities of the petroleum industry and review what is known about the sensitivity of peatlands to these activities. We find that 8.3% (107,000 km2) of the total area of tropical peatlands overlaps with a 30-km buffer area around oil and gas infrastructure. Major areas of overlap include the Sumatra Basin (Indonesia), the Niger Delta (Nigeria) and the Putumayo-Oriente-Marañón Basin (Peru/Ecuador/Colombia). Documented environmental impacts include deforestation and habitat loss associated with the exploration and development of oil fields, and contamination from spills of oil and produced water (well brine). Peatlands, and the ecosystem services they provide, are sensitive to these impacts due to unique aspects of their ecology and hydrology, the easy spread of contamination by flowing water, the long-term storage of contaminants in peat, and the slow degradation of oil under anoxic, waterlogged conditions. Given the potential negative consequences for human health, resource security, biodiversity, and carbon storage, we propose a research agenda to provide an improved evidence base to support effective governance.Publisher PDFPeer reviewe

Forest fire history in Amazonia inferred from intensive soil charcoal sampling and radiocarbon dating

This study was supported by funding from the UK Natural Environment Research Council (NERC, NE/N011570/1 and NE/R017980/1) and a radiocarbon dating allocation (allocation 2122.0818) from the NERC-funded NEIF Radiocarbon Laboratory.Fire has a historical role in tropical forests related to past climate and ancient land use spanning the Holocene; however, it is unclear from charcoal records how fire varied at different spatiotemporal scales and what sampling strategies are required to determine fire history and their effects. We evaluated fire variation in structurally intact, terra-firme Amazon forests, by intensive soil charcoal sampling from three replicate soil pits in sites in Guyana and northern and southern Peru. We used radiocarbon (14C) measurement to assess (1) locally, how the timing of fires represented in our sample varied across the surface of forest plots and with soil depth, (2) basin-wide, how the age of fires varies across climate and environmental gradients, and (3) how many samples are appropriate when applying the 14C approach to assess the date of last fire. Considering all 14C dates (n = 33), the most recent fires occurred at a similar time at each of the three sites (median ages: 728–851 cal years BP), indicating that in terms of fire disturbance at least, these forests could be considered old-growth. The number of unique fire events ranged from 1 to 4 per pit and from 4 to 6 per site. Based upon our sampling strategy, the N-Peru site—with the highest annual precipitation—had the most fire events. Median fire return intervals varied from 455 to 2,950 cal years BP among sites. Based on available dates, at least three samples (1 from the top of each of 3 pits) are required for the sampling to have a reasonable likelihood of capturing the most recent fire for forests with no history of a recent fire. The maximum fire return interval for two sites was shorter than the time since the last fire, suggesting that over the past ∼800 years these forests have undergone a longer fire-free period than the past 2,000–3,500 years. Our analysis from terra-firme forest soils helps to improve understanding of changes in fire regime, information necessary to evaluate post-fire legacies on modern vegetation and soil and to calibrate models to predict forest response to fire under climate change.Publisher PDFPeer reviewe

Dra. Nállarett Marina Dávila Cardozo, 1980-2022

Nállarett, conocida en varios paı́ses de forma cariñosa como Gigi, era una gran botánica y cientı́fica, además de ser una persona dulce, empática, creativa y brillante. Ella deja un gran legado cientı́fico en sus docenas de artı́culos, sus miles de especı́menes botánicos colectados y sus descripciones de varias especies nuevas para la ciencia. Será recordada por todos los botánicos que cruzan caminos con Caraipa davilae y Compsoneura nallarettiana, ambas especies endémicas del Perú, nombradas en su honor. Nállarett era una especialista y apasionada en bosques de arena blanca, hábitats de suelos pobres dentro de la cuenca amazónica que para ella resultaron áreas fértiles para estudiar la evolución de las maravillosas plantas que los habitan. Igualmente, deja un gran legado humano por su bella forma de ser, su generosidad y su sonrisa luminosa, marcando la vida de sus amigos y colegas de forma profunda. Nállarett es y será extrañada entrañablemente por todos quienes tuvimos la suerte de conocerla. Que descanse en paz

Can timber provision from Amazonian production forests be sustainable?

Around 30 Mm3 of sawlogs are extracted annually by selective logging of natural production forests in Amazonia, Earth's most extensive tropical forest. Decisions concerning the management of these production forests will be of major importance for Amazonian forests' fate. To date, no regional assessment of selective logging sustainability supports decision-making. Based on data from 3500 ha of forest inventory plots, our modelling results show that the average periodic harvests of 20 m3 ha−1 will not recover by the end of a standard 30 year cutting cycle. Timber recovery within a cutting cycle is enhanced by commercial acceptance of more species and with the adoption of longer cutting cycles and lower logging intensities. Recovery rates are faster in Western Amazonia than on the Guiana Shield. Our simulations suggest that regardless of cutting cycle duration and logging intensities, selectively logged forests are unlikely to meet timber demands over the long term as timber stocks are predicted to steadily decline. There is thus an urgent need to develop an integrated forest resource management policy that combines active management of production forests with the restoration of degraded and secondary forests for timber production. Without better management, reduced timber harvests and continued timber production declines are unavoidable