Gustafsson M.,Swedish University of Agricultural Sciences |
Gustafsson L.,Swedish University of Agricultural Sciences |
Alloysius D.,Yayasan Sabah Group |
Falck J.,Swedish University of Agricultural Sciences |
And 3 more authors.
Forest Ecology and Management | Year: 2016
Rainforest restoration is an important application in today's multipurpose management of secondary forest. However, our knowledge of tree species' traits and responses to treatment is insufficient for foresters to make good decisions for sustainable management. The aim of our study was to see whether it is possible to predict tree species' responses to increased light based on species' traits, and to relate these responses to a possible pioneer-climax continuum of life history traits, also among species with presumed climax properties. We examined 33 taxa (including 19 from the dipterocarp family) replicated 20 times and randomly planted in lines over a 3. ha area in the interior of Sabah, Borneo. Four years after establishment we performed a canopy reduction treatment to increase the light conditions up to levels present in tree gaps in the forest. We created a PLS (Partial Least Square Regressions) model with the two predicted variables HGR (height growth response) and Q3 HGR (the 75 percentile of a species' HGR, interpreted as the potential HGR). The model captured 47% of the variation for the predicted variables. We found significant tree species' responses in height growth to the increased light. High specific leaf area, strong early height growth, high foliar N content, high leaved stem length and large crown were linked to fast growth, while high wood density and high foliar K content were associated with slow growth. We also found a trade-off between growth response and survival among the species. We conclude that climax tree species have specific life history adaptations along a pioneer-climax continuum, which can be predicted from species' traits. The importance of easily observed or extracted traits such as initial growth rate, specific leaf area and wood density for predicting growth suggests the possibility of fast screening of species with unknown characteristics, which could be of great value in practical forest management. © 2015 Elsevier B.V.
Ewers R.M.,Imperial College London |
Didham R.K.,University of Western Australia |
Didham R.K.,CSIRO |
Didham R.K.,University of Canterbury |
And 12 more authors.
Philosophical Transactions of the Royal Society B: Biological Sciences | Year: 2011
Opportunities to conduct large-scale field experiments are rare, but provide a unique opportunity to reveal the complex processes that operate within natural ecosystems. Here, we review the design of existing, large-scale forest fragmentation experiments. Based on this review, we develop a design for the Stability of Altered Forest Ecosystems (SAFE) Project, a new forest fragmentation experiment to be located in the lowland tropical forests of Borneo (Sabah,Malaysia). The SAFE Project represents an advance on existing experiments in that it: (i) allows discrimination of the effects of landscape-level forest cover from patch-level processes; (ii) is designed to facilitate the unification of a wide range of data types on ecological patterns and processes that operate over a wide range of spatial scales; (iii) has greater replication than existing experiments; (iv) incorporates an experimental manipulation of riparian corridors; and (v) embeds the experimentally fragmented landscape within a wider gradient of land-use intensity than do existing projects. The SAFE Project represents an opportunity for ecologists across disciplines to participate in a large initiative designed to generate a broad understanding of the ecological impacts of tropical forest modification. © 2011 The Royal Society.
Monteuuis O.,CIRAD - Agricultural Research for Development |
Goh D.K.S.,Yayasan Sabah Group
Canadian Journal of Forest Research | Year: 2014
Teak (Tectona grandis L. f.) clonal forestry has lately become a reality thanks to the development of efficient techniques for mass clonally propagating true-to-type teak trees of various ages. Field trials were set up to assess the influence of teak genotypes of different ages and three clonal propagation techniques on field growth performances of teak clones. Significant differences (P < 0.0001) in height (H, from 11.9 to 17.5 m), diameter at breast height (D, from 11.8 to 18.9 cm), and volume (V, from 67.9 to 194.7 dm3) were observed 5 years after planting for clones produced by microcuttings from 6-month-old to 70-year-old teak ortets, regardless of their age. After 6.5 years of testing, H, D, and V performances of clones produced by rooted cuttings and microcuttings from 7-year-old teak trees were similar, notwithstanding clone × propagation method interactions. Five years after planting, clones produced by meristem culture from 7-year-old ortets had larger diameters and volumes than clones produced by microcuttings, whereas H varied according to clone × propagation method interaction. The various propagation methods used had no significant effect on mortality (<10%). The pros and cons of these techniques for mass clonally propagating teak genotypes of different ages were discussed. © 2015 National Research Council of Canada. All rights reserved.
Goh D.K.S.,Yayasan Sabah Group |
Bacilieri R.,Montpellier SupAgro |
Chaix G.,University of Sao Paulo |
Monteuuis O.,CIRAD - Agricultural Research for Development
Tree Genetics and Genomes | Year: 2013
Sixteen families derived from a clonal seed orchard (CSO) and 10 "provenances" (Prov) of teak (Tectona grandis) were tested in two different sites to be compared with respect to their growth performances. Both sites were located in Sabah, East Malaysia, under 2,500 mm of annual rainfall and no distinct dry season. The land in Taliwas was flat but prone to waterlogging. In Luasong, the soil was more hilly, acidic, and less fertile, though deeper. Nearly 9 years after planting, the two classes of genetic entries showed significant differences for height (P = 0.0002) and diameter at breast height (DBH) and volume (P < 0.0001) for the two sites combined. The superiority of the CSO families compared with the Prov class was more obvious in Luasong with averages of 18.0 vs 15.2 m (+18.6 %) for height, 18.1 vs 15.1 cm (+20.2 %) for DBH, and 0.179 vs 0.107 m3 for individual tree volume (+67.9 %), as against 17.4 vs 15.7 m (+11.2 %), 19.1 vs 16.8 cm (+13.5 %), and 0.176 vs 0.126 m3 (+40.3 %), respectively, in Taliwas. The CSO families were also more prone to site interaction for height (P = 0.004) and, to a lesser extent, for volume (P = 0.017) than the "Prov" (P = 0.030 and P = 0.057, respectively). Narrow-sense heritabilities estimated for the 16 CSO families across the two sites were lower for DBH (0.17) and volume (0.23) than for height (0.38). Type B genetic correlations suggested also higher site × families interactions for height (r B = 0.28). © 2013 Springer-Verlag Berlin Heidelberg.
Perrineau M.M.,CIRAD - Agricultural Research for Development |
Le Roux C.,CIRAD - Agricultural Research for Development |
Galiana A.,CIRAD - Agricultural Research for Development |
Faye A.,Laboratoire Communications Of Microbiologie |
And 4 more authors.
Applied and Environmental Microbiology | Year: 2014
Introducing nitrogen-fixing bacteria as an inoculum in association with legume crops is a common practice in agriculture. However, the question of the evolution of these introduced microorganisms remains crucial, both in terms of microbial ecology and agronomy. We explored this question by analyzing the genetic and symbiotic evolution of two Bradyrhizobium strains inoculated on Acacia mangium in Malaysia and Senegal 15 and 5 years, respectively, after their introduction. Based on typing of several loci, we showed that these two strains, although closely related and originally sampled in Australia, evolved differently. One strain was recovered in soil with the same five loci as the original isolate, whereas the symbiotic cluster of the other strain was detected with no trace of the three housekeeping genes of the original inoculum. Moreover, the nitrogen fixation efficiency was variable among these isolates (either recombinant or not), with significantly high, low, or similar efficiencies compared to the two original strains and no significant difference between recombinant and nonrecombinant isolates. These data suggested that 15 years after their introduction, nitrogen-fixing bacteria remain in the soil but that closely related inoculant strains may not evolve in the same way, either genetically or symbiotically. In a context of increasing agronomical use of microbial inoculants (for biological control, nitrogen fixation, or plant growth promotion), this result feeds the debate on the consequences associated with such practices. © 2014, American Society for Microbiology. All Rights Reserved.