An estimate of the number of tropical tree species

The high species richness of tropical forests has long been recognized, yet there remains substantial uncertainty regarding the actual number of tropical tree species. Using a pantropical tree inventory database from closed canopy forests, consisting of 657,630 trees belonging to 11,371 species, we use a fitted value of Fisher’s alpha and an approximate pantropical stem total to estimate the minimum number of tropical forest tree species to fall between ∼40,000 and ∼53,000, i.e. at the high end of previous estimates. Contrary to common assumption, the Indo-Pacific region was found to be as species-rich as the Neotropics, with both regions having a minimum of ∼19,000–25,000 tree species. Continental Africa is relatively depauperate with a minimum of ∼4,500–6,000 tree species. Very few species are shared among the African, American, and the Indo-Pacific regions. We provide a methodological framework for estimating species richness in trees that may help refine species richness estimates of tree-dependent taxa

Phylogenetic classification of the world's tropical forests

Knowledge about the biogeographic affinities of the world’s tropical forests helps to better understand regional differences in forest structure, diversity, composition, and dynamics. Such understanding will enable anticipation of region-specific responses to global environmental change. Modern phylogenies, in combination with broad coverage of species inventory data, now allow for global biogeographic analyses that take species evolutionary distance into account. Here we present a classification of the world’s tropical forests based on their phylogenetic similarity. We identify five principal floristic regions and their floristic relationships: (i) Indo-Pacific, (ii) Subtropical, (iii) African, (iv) American, and (v) Dry forests. Our results do not support the traditional neo- versus paleotropical forest division but instead separate the combined American and African forests from their Indo-Pacific counterparts. We also find indications for the existence of a global dry forest region, with representatives in America, Africa, Madagascar, and India. Additionally, a northern-hemisphere Subtropical forest region was identified with representatives in Asia and America, providing support for a link between Asian and American northern-hemisphere forests.</p

The large Gunnera's (G. tinctoria and G. manicata) in Europe in relation to EU regulation 1143/2014.

Incorrect labelling of plants in the horticultural trade and misidentification is widespread. For the inspection services of the EU member states, correct identification of G. tinctoria has become important since the species was added to the List of Union concern in accordance with EU regulation 1143/2014 in August 2017. In the horticultural trade Gunnera plants are generally of modest dimensions and rarely flowering, so that the major distinguishing morphological characters for the identification of the two large species, G. tinctoria and G. manicata, are missing. As G. tinctoria is included in the EU regulation, its trade is prohibited, although the closely related species, G. manicata is not included on the list. Given that it is often difficult to distinguish between these two large herbaceous species using morphological attributes we used standard chloroplast DNA barcode markers, supplemented at a later stage by ITS markers. Plant material of putative G. tinctoria or G. manicata was obtained from the native and introduced range, both from "wild" sources, botanical gardens, and the horticultural trade. In western Europe plants circulating in the horticultural trade turned out to be predominantly G. tinctoria, with only one plant in cultivation identified as true G. manicata and the G. manicata found in botanical gardens was a hybrid recently described as G. x cryptica

A floristic inventory and preliminary vegetation classification of the mixed semi-evergreen rain forest in the Mink\ue9b\ue9 region, North East Gabon

Volume: 20Start Page: 139End Page: 16

Myriophyllum rubricaule sp. nov., a M. aquaticum look-alike only known in cultivation

A confusingly labeled water-milfoil of obscure status, known only in cultivation, is here formally described as a new species, Myriophyllum rubricaule Valk. & Duist. sp. nov. This species has fully replaced M. aquaticum in the horticultural trade in Europe since the addition of M. aquaticum to the list of invasive alien species of Union concern (EU regulation no. 1143/2014) in 2016. This manuscript provides a morphological description of M. rubricaule sp. nov., and its distinction from M. aquaticum is further supported by molecular data (chloroplast and nuclear loci)

Physical Activity Is Associated with Improved Overall Survival among Patients with Metastatic Colorectal Cancer

SIMPLE SUMMARY: Physical activity is linked to longer survival among non-metastasized colorectal cancer patients. It is unclear if physical activity is also beneficial for survival among patients with metastatic colorectal cancer. We researched this question in our study of 293 patients with metastatic colorectal cancer. We found that participants who reported higher levels of physical activity at diagnosis lived longer compared to patients who reported low activity levels. Furthermore, adherence to the physical activity guidelines for cancer survivors was related to prolonged survival. Our findings suggest that patients with metastatic colorectal cancer also benefit from being physically active. Future studies are needed to investigate whether improving exercise levels after diagnosis of metastasis is also beneficial and what kind of exercise interventions are most optimal for possibly improving survival time of patients with metastatic colorectal cancer. ABSTRACT: Regular physical activity (PA) is associated with improved overall survival (OS) in stage I–III colorectal cancer (CRC) patients. This association is less defined in patients with metastatic CRC (mCRC). We therefore conducted a study in mCRC patients participating in the Prospective Dutch Colorectal Cancer cohort. PA was assessed with the validated SQUASH questionnaire, filled-in within a maximum of 60 days after diagnosis of mCRC. PA was quantified by calculating Metabolic Equivalent Task (MET) hours per week. American College of Sports and Medicine (ACSM) PA guideline adherence, tertiles of moderate to vigorous PA (MVPA), and sport and leisure time MVPA (MVPA-SL) were assessed as well. Vital status was obtained from the municipal population registry. Cox proportional-hazards models were used to study the association between PA determinants and all-cause mortality adjusted for prognostic patient and treatment-related factors. In total, 293 mCRC patients (mean age 62.9 ± 10.6 years, 67% male) were included in the analysis. Compared to low levels, moderate and high levels of MET-hours were significantly associated with longer OS (fully adjusted hazard ratios: 0.491, (95% CI 0.299–0.807, p value = 0.005) and 0.485 (95% CI 0.303–0.778, p value = 0.003), respectively), as were high levels of MVPA (0.476 (95% CI 0.278–0.816, p value = 0.007)) and MVPA-SL (0.389 (95% CI 0.224–0.677, p value < 0.001)), and adherence to ACSM PA guidelines compared to non-adherence (0.629 (95% CI 0.412–0.961, p value = 0.032)). The present study provides evidence that higher PA levels at diagnosis of mCRC are associated with longer OS