Near-ground growth offers lowstatured plants many benefi ts but also exposes them to the risk of being overtopped and losing access to sunlight. Plant community development is often portrayed as a process of serial dominance by... more
Near-ground growth offers lowstatured plants many benefi ts
but also exposes them to the risk
of being overtopped and losing
access to sunlight. Plant community
development is often portrayed
as a process of serial dominance
by successively taller species, but
here we describe a mechanism by
which a low-growing rosette species
alters community spatial structure.
Elephantopus elatus (Asteraceae),
an herbaceous savanna plant with
low-growing leaves that emerge
radially from a central bud, pushes
neighboring plants away and thereby
avoids being overtopped. Active
pushing is possible because the leaves
have stout petioles that are basally
anchored rather than attached to
fl exible twigs or stems. This growthmediated leaf pushing introduces
a novel example of active plant
interactions that is likely important for
other rosette plants.
but also exposes them to the risk
of being overtopped and losing
access to sunlight. Plant community
development is often portrayed
as a process of serial dominance
by successively taller species, but
here we describe a mechanism by
which a low-growing rosette species
alters community spatial structure.
Elephantopus elatus (Asteraceae),
an herbaceous savanna plant with
low-growing leaves that emerge
radially from a central bud, pushes
neighboring plants away and thereby
avoids being overtopped. Active
pushing is possible because the leaves
have stout petioles that are basally
anchored rather than attached to
fl exible twigs or stems. This growthmediated leaf pushing introduces
a novel example of active plant
interactions that is likely important for
other rosette plants.
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colonizes and rapidly dies. The upper end of sapling mortality and growth distributions in America is set by gap specialists: C. obtusifolia at BCI (12 % yearj1 mortality, 14 % yearj1 growth), C. sciadophylla at Yasuni (5.0% yearj1... more
colonizes and rapidly dies. The upper end of sapling mortality and growth distributions in America is set by gap specialists: C. obtusifolia at BCI (12 % yearj1 mortality, 14 % yearj1 growth), C. sciadophylla at Yasuni (5.0% yearj1 mortality, 6.3 % yearj1 growth), and C. monostachya at La Planada (8.8 % yearj1 mortality, 8.2 % yearj1 growth). Diverse South-east Asian forests lacked species with such high rates (27). The most diverse tropical forests are the least diverse demographically. It remains plau-sible that demographic niches are packed more tightly in some forests than others, but this seems unlikely, because packing should depend only on population size and turnover, which do not vary much. Moreover, the successional-niche hypothesis is not favored by the strong peak in demographic rates near 1 to 2 % yearj1; if demographic niches were crucial, then rates ought to be spread evenly over the entire range (28). Instead, the similarity in demography of many species suggests tra...
colonizes and rapidly dies. The upper end of sapling mortality and growth distributions in America is set by gap specialists: C. obtusifolia at BCI (12 % yearj1 mortality, 14 % yearj1 growth), C. sciadophylla at Yasuni (5.0% yearj1... more
colonizes and rapidly dies. The upper end of sapling mortality and growth distributions in America is set by gap specialists: C. obtusifolia at BCI (12 % yearj1 mortality, 14 % yearj1 growth), C. sciadophylla at Yasuni (5.0% yearj1 mortality, 6.3 % yearj1 growth), and C. monostachya at La Planada (8.8 % yearj1 mortality, 8.2 % yearj1 growth). Diverse South-east Asian forests lacked species with such high rates (27). The most diverse tropical forests are the least diverse demographically. It remains plau-sible that demographic niches are packed more tightly in some forests than others, but this seems unlikely, because packing should depend only on population size and turnover, which do not vary much. Moreover, the successional-niche hypothesis is not favored by the strong peak in demographic rates near 1 to 2 % yearj1; if demographic niches were crucial, then rates ought to be spread evenly over the entire range (28). Instead, the similarity in demography of many species suggests tra...
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HARDIANSYAH G, RUSLANDI, HIDAYAT D, NUGRAHA A, MAHARDI M & PUTZ FE .2015. Clear bole lengths and crown characteristics of line-planted and naturally-regenerated Shorea leprosula trees: a case study from Kalimantan, Indonesia. Shorea... more
HARDIANSYAH G, RUSLANDI, HIDAYAT D, NUGRAHA A, MAHARDI M & PUTZ FE .2015. Clear bole lengths and crown characteristics of line-planted and naturally-regenerated Shorea leprosula trees: a case study from Kalimantan, Indonesia. Shorea leprosula seedlings planted at 5-m intervals along 3-m wide cleared lines at 20-m intervals through twice-logged forests in Kalimantan grew rapidly in dbh (diameter at 1.3 m) but at age 14–15 years, had branch-free stems that averaged 11% shorter than those of naturally-regenerated trees of the same dbh (20–40 cm). There was no relationship between clear bole length and terrain slope or current crown exposure. If low branches continue to be maintained until the harvest (planned at 25 years), commercial timber yields will be lower than predicted from allometrical relationships calculated using data from naturally-regenerated trees. Even if low branches on the planted trees are shed before harvest, log values will be reduced due to the presence of large kn...
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... PUB TYPE: Book (ISBN 0874747147 ). VOLUME/EDITION: PAGES (INTRO/BODY): x,. SUBJECT(S): Latin America in art; Exoticism in art; Art, American; Art, Modern; 19th century; United States. DISCIPLINE: No discipline assigned. LC NUMBER:... more
... PUB TYPE: Book (ISBN 0874747147 ). VOLUME/EDITION: PAGES (INTRO/BODY): x,. SUBJECT(S): Latin America in art; Exoticism in art; Art, American; Art, Modern; 19th century; United States. DISCIPLINE: No discipline assigned. LC NUMBER: N8214.5.U6 M3 1989. HTTP: ...
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... Numerous measures have been proposed to improve forest management including, among other recommendations, full commercial tree censuses, improved road planning, liana cutting on harvestable trees, seed tree retention, higher harvest... more
... Numerous measures have been proposed to improve forest management including, among other recommendations, full commercial tree censuses, improved road planning, liana cutting on harvestable trees, seed tree retention, higher harvest diameter limits and liberation of ...
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Changes in climate and land use that interact synergistically to increase fire frequencies and intensities in tropical regions are predicted to drive forests to new grass-dominated stable states. To reveal the mechanisms for such a... more
Changes in climate and land use that interact synergistically to increase fire frequencies and intensities in tropical regions are predicted to drive forests to new grass-dominated stable states. To reveal the mechanisms for such a transition, we established 50 ha plots in a transitional forest in the southwestern Brazilian Amazon to different fire treatments (unburned, burned annually (B1 yr ) or at 3-year intervals (B3 yr )). Over an 8-year period since the commencement of these treatments, we documented: (i) the annual rate of pasture and native grass invasion in response to increasing fire frequency; (ii) the establishment of Brachiaria decumbens (an African C 4 grass) as a function of decreasing canopy cover and (iii) the effects of grass fine fuel on fire intensity. Grasses invaded approximately 200 m from the edge into the interiors of burned plots (B1 yr : 4.31 ha; B3 yr : 4.96 ha) but invaded less than 10 m into the unburned plot (0.33 ha). The probability of B. decumbens e...
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colonizes and rapidly dies. The upper end of sapling mortality and growth distributions in America is set by gap specialists: C. obtusifolia at BCI (12 % yearj1 mortality, 14 % yearj1 growth), C. sciadophylla at Yasuni (5.0% yearj1... more
colonizes and rapidly dies. The upper end of sapling mortality and growth distributions in America is set by gap specialists: C. obtusifolia at BCI (12 % yearj1 mortality, 14 % yearj1 growth), C. sciadophylla at Yasuni (5.0% yearj1 mortality, 6.3 % yearj1 growth), and C. monostachya at La Planada (8.8 % yearj1 mortality, 8.2 % yearj1 growth). Diverse South-east Asian forests lacked species with such high rates (27). The most diverse tropical forests are the least diverse demographically. It remains plau-sible that demographic niches are packed more tightly in some forests than others, but this seems unlikely, because packing should depend only on population size and turnover, which do not vary much. Moreover, the successional-niche hypothesis is not favored by the strong peak in demographic rates near 1 to 2 % yearj1; if demographic niches were crucial, then rates ought to be spread evenly over the entire range (28). Instead, the similarity in demography of many species suggests tra...
Water relations of epiphytic and terrestrially-rooted strangler figs
SUMMARY After more than 20 years and substantial investments of time and money, Forest Stewardship Council (FSC) certification of tropical forest management is due for a stringent impact evaluation. For any social, ecological, and... more
SUMMARY After more than 20 years and substantial investments of time and money, Forest Stewardship Council (FSC) certification of tropical forest management is due for a stringent impact evaluation. For any social, ecological, and economic outcomes to be attributed to FSC certification, rival explanations need to be ruled out. We recognize that different types of knowledge about FSC impacts derived from information gathered through a range of methods can satisfy the evidence-needs of different stakeholders. But this paper describes a roadmap based on rigorous methods to assess whether FSC certification delivers on its expected outcomes and the underlying mechanisms through which changes can be attributable to FSC. To this end, background studies that provide contextual knowledge related to implementation of FSC certification are proposed to account for any positive self-selection biases and to capture the temporal dynamics of certification including changes in the sociopolitical and...
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Making knowledge work for forests and people Effects of forest certification on biodiversity
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... Beberapa jenis pepanjat bergantung dari segi biomekanikal kepada tumbuhan pepanjat yang lain yang menghasilkan warisan penjajahan pepanjat yang berturut ... in eastern Sabah, Malaysia (9782 km -, state commercial forest, latitude 5°... more
... Beberapa jenis pepanjat bergantung dari segi biomekanikal kepada tumbuhan pepanjat yang lain yang menghasilkan warisan penjajahan pepanjat yang berturut ... in eastern Sabah, Malaysia (9782 km -, state commercial forest, latitude 5° 0'N, longitude 117° 30'E, ca200 m ...
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In 13 ha of virgin dipterocarp forest of Sungai Tekam Forest Reserve, Pahang (Peninsular Malaysia), there were an average of 376 climbers/ha 2 cm dbh (diameter at 1.3 m from the ground). Cutting of climbers before logging reduced the... more
In 13 ha of virgin dipterocarp forest of Sungai Tekam Forest Reserve, Pahang (Peninsular Malaysia), there were an average of 376 climbers/ha 2 cm dbh (diameter at 1.3 m from the ground). Cutting of climbers before logging reduced the number of trees pulled down ...
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The experiences of a community group in Florida that sponsored a campaign to curb local expansion of Sapium sebijerum (tallow tree), an invasive exotic tree, may be useful for other exotic species control programs. Success of the tallow... more
The experiences of a community group in Florida that sponsored a campaign to curb local expansion of Sapium sebijerum (tallow tree), an invasive exotic tree, may be useful for other exotic species control programs. Success of the tallow replacement program was due, in part, to a partnership formed with the nursery industry. Convincing the public that not all trees are environmentally beneficial and enlisting public participation in the campaign were major challenges. Assistance came in the unexpected form of several vitriolic letters to the editor of the local newspaper in which the sponsors of the program were condemned for believing that they had the right to determine the fate of a tree, even an invasive exotic. The published exchange of letters was beneficial insofar as it kept the issue of exotics prominently in the public eye.
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An article in Land Use Policy published early in 2016 concluded that deforestation in Congo was highest in forest concessions with forest management plans (FMPs) than in those without. The impact assessment analysis which led the... more
An article in Land Use Policy published early in 2016 concluded that deforestation in Congo was highest in forest concessions with forest management plans (FMPs) than in those without. The impact assessment analysis which led the researchers to this conclusion is based on matching randomly selected plots in concessions with and without management plans. The researchers suggest that one factor is the more developed network of forest roads in managed concessions. Another factor is local development, which ensues from mandatory requirements for FMPs and leads to increases in population on FMP concessions and subsequently increased deforestation. Our group of twenty researchers, knowledgeable of forest management issues in Central Africa, analyzed deforestation in concessions over the same time period. Our results show that deforestation is lower in concessions with FMPs than in those without. In a comparative analysis of deforestation with production remaining constant, concessions wit...
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1. Mikania scandens plants of three stem-length classes: small ( 10 cm), were transplanted into flooded or drained soil. After six weeks the relative growth rates (RGR), based on both dry weight and stem elongation, of the small plants... more
1. Mikania scandens plants of three stem-length classes: small ( 10 cm), were transplanted into flooded or drained soil. After six weeks the relative growth rates (RGR), based on both dry weight and stem elongation, of the small plants under flooded conditions were 50% greater than those in drained soil. For the medium and large classes, the RGR values of the drained and flooded plants were similar. 2. Stem and root cross-sections revealed that flooded plants had two- and threefold respectively more aerenchyma tissue, with the amount in the stem decreasing in an acropetal direction. The stem surface contained stomata, not lenticels. The mean number of stem stomata was 267 and 57 for flooded and drained plants respectively on the 21 cm stem section above the water or soil line
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... forest management for com-mercial production of timber and non-timber forest products is to ... In developing ecological certification criteria for forest products, the accumulating evidence that many ... activities with the... more
... forest management for com-mercial production of timber and non-timber forest products is to ... In developing ecological certification criteria for forest products, the accumulating evidence that many ... activities with the consequences of "liquidation log-ging" and forest conversion to ...
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When 2 Mha of Amazonian forests are disturbed by selective logging each year, more than 90 Tg of carbon (C) is emitted to the atmosphere. Emissions are then counterbalanced by forest regrowth. With an original modelling approach,... more
When 2 Mha of Amazonian forests are disturbed by selective logging each year, more than 90 Tg of carbon (C) is emitted to the atmosphere. Emissions are then counterbalanced by forest regrowth. With an original modelling approach, calibrated on a network of 133 permanent forest plots (175 ha total) across Amazonia, we link regional differences in climate, soil and initial biomass with survivors' and recruits' C fluxes to provide Amazon-wide predictions of post-logging C recovery. We show that net aboveground C recovery over 10 years is higher in the Guiana Shield and in the west (21 ±3 Mg C ha-1) than in the south (12 ±3 Mg C ha-1) where environmental stress is high (low rainfall, high seasonality). We highlight the key role of survivors in the forest regrowth and elaborate a comprehensive map of post-disturbance C recovery potential in Amazonia.
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Research Highlights: Tree size and wood characteristics influenced the susceptibility of five Amazonian timber tree species to heartwood decay and colonization by termites. Termites occurred in the heartwoods of 43% of the trees, with... more
Research Highlights: Tree size and wood characteristics influenced the susceptibility of five Amazonian timber tree species to heartwood decay and colonization by termites. Termites occurred in the heartwoods of 43% of the trees, with Coptotermes testaceus the most abundant species. Background and Objectives: Hollows and rotten cores in the stems of living trees have ecological and economic impacts in forests managed for timber. The decision on whether to cut or maintain hollow trees in such forests must account for the susceptibility of different tree species to decay. We investigated tree and wood characteristics of living trees of five commercial timber species in the eastern Amazon that influenced the likelihood of heartwood decay and the occurrence of termite nests inside the rotten cores. Materials and Methods: We used Pearson’s correlations and one-way analysis of variance (ANOVA) to explore relationships among tree basal area and hollow area. We used principal components ana...
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Payments for ecosystems services (PES) can promote natural resource conservation by increasing compliance with environmental laws. Law enforcement and PES proponents assume that individuals make decisions about compliance based on... more
Payments for ecosystems services (PES) can promote natural resource conservation by increasing compliance with environmental laws. Law enforcement and PES proponents assume that individuals make decisions about compliance based on expectations of gains, likelihood of being caught in non-compliance, and magnitude of sanctions. Brazil’s Forest Code, characterized by low levels of compliance, includes incentive and disincentive mechanisms. We interviewed landowners in the Atlantic Forest to understand their motivations to participate (or not) in a PES project, the effects of knowledge and perceptions of environmental regulations on compliance, and how both environmental regulations and PES affect land management decision-making. We found that neither expectations of financial gains nor PES payments drive behavioral change and that the perception of systemic corruption reduced compliance with environment regulations. There were important behavioral differences between long-term resident...
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We compared stump sprouting by three common timber species in Suriname on the basis of sprout origins on stumps, sprout densities, and sprout height:diameter ratios. We then compared some leaf and stem functional traits of 15–18-month-old... more
We compared stump sprouting by three common timber species in Suriname on the basis of sprout origins on stumps, sprout densities, and sprout height:diameter ratios. We then compared some leaf and stem functional traits of 15–18-month-old resprouts and nearby conspecific saplings of the same height (0.5–3.5 m) but unknown age. Stumps of Dicorynia guianensis Amsh. (29–103 cm in diameter) produced the most sprouts (x = 9.2/stump), followed by the 50–71 cm diameter stumps of Eperua falcata Amsh. (10.6/stump), and the 30–78 cm diameter Qualea rosea Amsh. (5.9/stump); sprout density did not vary with stump diameter. Sprouts emerged from the lower, middle, and upper thirds of the stumps of all three species, but not from the vicinity of the exposed vascular cambium in Qualea. With increased resprout density, heights of the tallest sprout per stump tended to increase but height:diameter ratios increased only in Dicorynia. Compared to conspecific saplings, sprouts displayed higher height-di...
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Borneo differs fundamentally from Canada, but reflections on the struggles to improve the fates of its tropical rain forests may resonate with people engaged in the same struggles on the other side of the Pacific. I frame these... more
Borneo differs fundamentally from Canada, but reflections on the struggles to improve the fates of its tropical rain forests may resonate with people engaged in the same struggles on the other side of the Pacific. I frame these reflections around the question of why my efforts as a researcher in Borneo failed to cause a change from predatory logging of old growth to conservation through improved forest management. Perhaps my most fundamental mistake was unwillingness to recognize the immense profitability of forest liquidation through multiple-premature re-entry logging, especially when followed by conversion to plantations of African oil palm or Australian acacias. Superimposed on the high opportunity costs of conservation were governance failures that diminished the effectiveness of policies set by government as well as those set by certifiers of responsible management. Conservation of the mostly remote, flooded, and steep hinterlands still covered by forest will benefit from ackn...
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Forest degradation accounts for ~70% of total carbon losses from tropical forests. Substantial emissions are from selective logging, a land-use activity that decreases forest carbon density. To maintain carbon values in selectively logged... more
Forest degradation accounts for ~70% of total carbon losses from tropical forests. Substantial emissions are from selective logging, a land-use activity that decreases forest carbon density. To maintain carbon values in selectively logged forests, climate change mitigation policies and government agencies promote the adoption of reduced-impact logging (RIL) practices. However, whether RIL will maintain both carbon and timber values in managed tropical forests over time remains uncertain. In this study, we quantify the recovery of timber stocks and aboveground carbon at an experimental site where forests were subjected to different intensities of RIL (4, 8, and 16 trees/ha). Our census data span 20 years postlogging and 17 years after the liberation of future crop trees from competition in a tropical forest on the Guiana Shield, a globally important forest carbon reservoir. We model recovery of timber and carbon with a breakpoint regression that allowed us to capture elevated tree mo...
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Better stewardship of land is needed to achieve the Paris Climate Agreement goal of holding warming to below 2 °C; however, confusion persists about the specific set of land stewardship options available and their mitigation potential. To... more
Better stewardship of land is needed to achieve the Paris Climate Agreement goal of holding warming to below 2 °C; however, confusion persists about the specific set of land stewardship options available and their mitigation potential. To address this, we identify and quantify "natural climate solutions" (NCS): 20 conservation, restoration, and improved land management actions that increase carbon storage and/or avoid greenhouse gas emissions across global forests, wetlands, grasslands, and agricultural lands. We find that the maximum potential of NCS-when constrained by food security, fiber security, and biodiversity conservation-is 23.8 petagrams of CO2 equivalent (PgCO2e) y-1 (95% CI 20.3-37.4). This is ≥30% higher than prior estimates, which did not include the full range of options and safeguards considered here. About half of this maximum (11.3 PgCO2e y-1) represents cost-effective climate mitigation, assuming the social cost of CO2 pollution is ≥100 USD MgCO2e-1 by ...
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Viña et al. imply that native forests account for China's marked increase in tree cover and that tree plantations play a minimal role. All 71 tweets linked to the article reinforce the idea that China's native forests are... more
Viña et al. imply that native forests account for China's marked increase in tree cover and that tree plantations play a minimal role. All 71 tweets linked to the article reinforce the idea that China's native forests are returning, whereas a review of their methodology indicates that it is not likely accurate. Referring news articles (n = 19) were dominated by terms associated with native forests, whereas tree plantations were rarely mentioned.
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Sea level rise elicits short- and long-term changes in coastal plant communities by altering the physical conditions that affect ecosystem processes and species distributions. While the effects of sea level rise on salt marshes and... more
Sea level rise elicits short- and long-term changes in coastal plant communities by altering the physical conditions that affect ecosystem processes and species distributions. While the effects of sea level rise on salt marshes and mangroves are well studied, we focus on its effects on coastal islands of freshwater forest in Florida's Big Bend region, extending a dataset initiated in 1992. In 2014-2015, we evaluated tree survival, regeneration, and understory composition in 13 previously established plots located along a tidal creek; 10 plots are on forest islands surrounded by salt marsh, and three are in continuous forest. Earlier studies found that salt stress from increased tidal flooding prevented tree regeneration in frequently flooded forest islands. Between 1992 and 2014, tidal flooding of forest islands increased by 22%-117%, corresponding with declines in tree species richness, regeneration, and survival of the dominant tree species, Sabal palmetto (cabbage palm) and J...
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ABSTRACT In their response to our recent article (Putz et al. 2012), Kormos and Zimmerman (K&Z) do not take issue with the result of our meta-analysis of more than 100 published studies that biodiversity and carbon stocks are... more
ABSTRACT In their response to our recent article (Putz et al. 2012), Kormos and Zimmerman (K&Z) do not take issue with the result of our meta-analysis of more than 100 published studies that biodiversity and carbon stocks are mostly retained in selectively logged tropical forests.