BioOne Complete (complete.BioOne.org) is a full-text database of 200 subscribed and open-access titles in the biological, ecological, and environmental sciences published by nonprofit societies, associations, museums, institutions, and presses.
Pollen analysis of a 150-cm-long core from Pantano de Pecho (0°20′S, 78°37′W) at 3870 m altitude in the Ecuadorian páramo documents altitudinal migrations and the composition of the upper forest line prior to deforestation. Four successive radiocarbon dates of 293 ± 41 14C y BP, 498 ± 40 14C y BP, 626 ± 33 14C y BP, and 729 ± 44 14C y BP show that the record includes the last c. 730 radiocarbon y, corresponding to the last c. 660 calendar years (cal y BP). The natural upper forest line was at a minimum altitude of 3400-3500 m between c. AD 1290 to 1315 (zone 1), from c. AD 1315 to 1350 at 3500-3600 m (zone 2), from c. AD 1350 to 1640 at 3600-3700 m (zone 3), from c. AD 1640 to c. 1765 at 3750 m (zone 4), and from c. AD 1765 to the present at 3700-3650 m (zone 5). The most important taxa were Alnus, Hedyosmum, Miconia, other Melastomataceae, Gunnera and Solanaceae. Since c. AD 1350 Podocarpus was continuously present with low abundance, but possibly not close to the upper forest line. Rarer elements of the upper montane forest were Dodonaea, Myrsine, Weinmannia, Myrica, Myrtaceae, Sapium, Juglans, Piper, Euphorbiaceae and Rubiaceae. Human disturbance and deforestation are shown by the presence of Rumex, Spermacoce pollen and charcoal particles. We surveyed the vegetation composition from isolated forest patches located between 3650 m and 4300 m. TWINSPAN analysis indicates forest patches up to 3950 m have a similar floristic composition to closed forest below the upper forest line. We argue that this apparent similarity does not necessarily mean that the slopes between 3750 and 3950 m were covered by closed forest in the past.
Pongo pygmaeus pygmaeus is a subspecies of Bornean orangutan whose distribution is restricted to the northern part of the Kapuas River, West Kalimantan, and is categorized as Critically Endangered. In October 2017 we carried out a survey to estimate orangutan density in the peat-swamp forests of the Sungai Palin watershed, of the upper Kapuas river, Kapuas Hulu, West Kalimantan, Indonesia. Surveys for orangutans in 1991, in nearby Nanga Awen, had indicated the presence of orangutans in the peat-swamp forests of this area. We used distance sampling techniques to estimate orangutan densities from nest observations. We recorded 76 orangutan nests along 4.5 km transects in Sungai Palin in 2017, and 71 orangutan nests were observed along 4.3 km transects in Nanga Awen in 1991, giving densities of 1.29 and 2.62 individuals/km2, respectively. The results of this orangutan survey can be used as a baseline for monitoring of orangutan populations for conservation and management of this watershed landscape.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.