Accurate inventory of tropical peatland is important in order to (a) determine the magnitude of the carbon pool; (b) estimate the scale of transfers of peat-derived greenhouse gases to the atmosphere ...resulting from land use change; and (c) support carbon emissions reduction policies. We review available information on tropical peatland area and thickness and calculate peat volume and carbon content in order to determine their best estimates and ranges of variation. Our best estimate of tropical peatland area is 441 025 km² (∼11% of global peatland area) of which 247 778 km² (56%) is in Southeast Asia. We estimate the volume of tropical peat to be 1758 Gm³ (∼18-25% of global peat volume) with 1359 Gm³ in Southeast Asia (77% of all tropical peat). This new assessment reveals a larger tropical peatland carbon pool than previous estimates, with a best estimate of 88.6 Gt (range 81.7-91.9 Gt) equal to 15-19% of the global peat carbon pool. Of this, 68.5 Gt (77%) is in Southeast Asia, equal to 11-14% of global peat carbon. A single country, Indonesia, has the largest share of tropical peat carbon (57.4 Gt, 65%), followed by Malaysia (9.1 Gt, 10%). These data are used to provide revised estimates for Indonesian and Malaysian forest soil carbon pools of 77 and 15 Gt, respectively, and total forest carbon pools (biomass plus soil) of 97 and 19 Gt. Peat carbon contributes 60% to the total forest soil carbon pool in Malaysia and 74% in Indonesia. These results emphasize the prominent global and regional roles played by the tropical peat carbon pool and the importance of including this pool in national and regional assessments of terrestrial carbon stocks and the prediction of peat-derived greenhouse gas emissions.
Peatlands are carbon-rich ecosystems that cover just three per cent of Earth's land surface, but store one-third of soil carbon. Peat soils are formed by the build-up of partially decomposed organic ...matter under waterlogged anoxic conditions. Most peat is found in cool climatic regions where unimpeded decomposition is slower, but deposits are also found under some tropical swamp forests. Here we present field measurements from one of the world's most extensive regions of swamp forest, the Cuvette Centrale depression in the central Congo Basin. We find extensive peat deposits beneath the swamp forest vegetation (peat defined as material with an organic matter content of at least 65 per cent to a depth of at least 0.3 metres). Radiocarbon dates indicate that peat began accumulating from about 10,600 years ago, coincident with the onset of more humid conditions in central Africa at the beginning of the Holocene. The peatlands occupy large interfluvial basins, and seem to be largely rain-fed and ombrotrophic-like (of low nutrient status) systems. Although the peat layer is relatively shallow (with a maximum depth of 5.9 metres and a median depth of 2.0 metres), by combining in situ and remotely sensed data, we estimate the area of peat to be approximately 145,500 square kilometres (95 per cent confidence interval of 131,900-156,400 square kilometres), making the Cuvette Centrale the most extensive peatland complex in the tropics. This area is more than five times the maximum possible area reported for the Congo Basin in a recent synthesis of pantropical peat extent. We estimate that the peatlands store approximately 30.6 petagrams (30.6 × 10
grams) of carbon belowground (95 per cent confidence interval of 6.3-46.8 petagrams of carbon)-a quantity that is similar to the above-ground carbon stocks of the tropical forests of the entire Congo Basin. Our result for the Cuvette Centrale increases the best estimate of global tropical peatland carbon stocks by 36 per cent, to 104.7 petagrams of carbon (minimum estimate of 69.6 petagrams of carbon; maximum estimate of 129.8 petagrams of carbon). This stored carbon is vulnerable to land-use change and any future reduction in precipitation.
Tropical peatlands of the western part of insular Southeast Asia have experienced extensive land cover changes since 1990. Typically involving drainage, these land cover changes have resulted in ...increased peat oxidation in the upper peat profile. In this paper we provide current (2015) and cumulative carbon emissions estimates since 1990 from peat oxidation in Peninsular Malaysia, Sumatra and Borneo, utilizing newly published peatland land cover information and the recently agreed Intergovernmental Panel on Climate Change (IPCC) peat oxidation emission values for tropical peatland areas. Our results highlight the change of one of the Earth's most efficient long-term carbon sinks to a short-term emission source, with cumulative carbon emissions since 1990 estimated to have been in the order of 2.5 Gt C. Current (2015) levels of emissions are estimated at around 146 Mt C yr−1, with a range of 132-159 Mt C yr−1 depending on the selection of emissions factors for different land cover types. 44% (or 64 Mt C yr−1) of the emissions come from industrial plantations (mainly oil palm and Acacia pulpwood), followed by 34% (49 Mt C yr−1) of emissions from small-holder areas. Thus, altogether 78% of current peat oxidation emissions come from managed land cover types. Although based on the latest information, these estimates may still include considerable, yet currently unquantifiable, uncertainties (e.g. due to uncertainties in the extent of peatlands and drainage networks) which need to be focused on in future research. In comparison, fire induced carbon dioxide emissions over the past ten years for the entire equatorial Southeast Asia region have been estimated to average 122 Mt C yr−1 (www.globalfiredata.org/_index.html). The results emphasise that whilst reducing emissions from peat fires is important, urgent efforts are also needed to mitigate the constantly high level of emissions arising from peat drainage, regardless of fire occurrence.
Tropical peatland fires play a significant role in the context of global warming through emissions of substantial amounts of greenhouse gases. However, the state of knowledge on carbon loss from ...these fires is still poorly developed with few studies reporting the associated mass of peat consumed. Furthermore, spatial and temporal variations in burn depth have not been previously quantified. This study presents the first spatially explicit investigation of fire‐driven tropical peat loss and its variability. An extensive airborne Light Detection and Ranging data set was used to develop a prefire peat surface modelling methodology, enabling the spatially differentiated quantification of burned area depth over the entire burned area. We observe a strong interdependence between burned area depth, fire frequency and distance to drainage canals. For the first time, we show that relative burned area depth decreases over the first four fire events and is constant thereafter. Based on our results, we revise existing peat and carbon loss estimates for recurrent fires in drained tropical peatlands. We suggest values for the dry mass of peat fuel consumed that are 206 t ha−1 for initial fires, reducing to 115 t ha−1 for second, 69 t ha−1 for third and 23 t ha−1 for successive fires, which are 58–7% of the current IPCC Tier 1 default value for all fires. In our study area, this results in carbon losses of 114, 64, 38 and 13 t C ha−1 for first to fourth fires, respectively. Furthermore, we show that with increasing proximity to drainage canals both burned area depth and the probability of recurrent fires increase and present equations explaining burned area depth as a function of distance to drainage canal. This improved knowledge enables a more accurate approach to emissions accounting and will support IPCC Tier 2 reporting of fire emissions.
Carbon emissions from drained peatlands converted to agriculture in South‐East Asia (i.e., Peninsular Malaysia, Sumatra and Borneo) are globally significant and increasing. Here, we map the growth of ...South‐East Asian peatland agriculture and estimate CO2 emissions due to peat drainage in relation to official land‐use plans with a focus on the reducing emissions from deforestation and degradation (REDD+)‐related Indonesian moratorium on granting new concession licences for industrial agriculture and logging. We find that, prior to 2010, 35% of South‐East Asian peatlands had been converted to agriculture, principally by smallholder farmers (15% of original peat extent) and industrial oil palm plantations (14%). These conversions resulted in 1.46–6.43 GtCO2 of emissions between 1990 and 2010. This legacy of historical clearances on deep‐peat areas will contribute 51% (4.43–11.45 GtCO2) of projected future peatland CO2 emissions over the period 2010–2130. In Indonesia, which hosts most of the region's peatland and where concession maps are publicly available, 70% of peatland conversion to agriculture occurred outside of known concessions for industrial plantation development, with smallholders accounting for 60% and industrial oil palm accounting for 34%. Of the remaining Indonesian peat swamp forest (PSF), 45% is not protected, and its conversion would amount to CO2 emissions equivalent to 0.7%–2.3% (5.14–14.93 Gt) of global fossil fuel and cement emissions released between 1990 and 2010. Of the peatland extent included in the moratorium, 48% was no longer forested, and of the PSF included, 40%–48% is likely to be affected by drainage impacts from agricultural areas and will emit CO2 over time. We suggest that recent legislation and policy in Indonesia could provide a means of meaningful emission reductions if focused on revised land‐use planning, PSF conservation both inside and outside agricultural concessions, and the development of agricultural practices based on rehabilitating peatland hydrological function.
Past and future emissions due to drainage based agriculture of Southeast Asian peatlands.
Splinting for carpal tunnel syndrome Karjalainen, Teemu V; Karjalainen, Teemu V; Lusa, Vieda ...
Cochrane database of systematic reviews,
02/2023, Letnik:
2023, Številka:
2
Journal Article
Recenzirano
Odprti dostop
Background
Carpal tunnel syndrome (CTS) is a compression neuropathy of the median nerve causing pain and numbness and tingling typically in the thumb, index and middle finger. It sometimes results in ...muscle wasting, diminished sensitivity and loss of dexterity. Splinting the wrist (with or without the hand) using an orthosis is usually offered to people with mild‐to‐moderate findings, but its effectiveness remains unclear.
Objectives
To assess the effects (benefits and harms) of splinting for people with CTS.
Search methods
On 12 December 2021, we searched the Cochrane Neuromuscular Specialised Register, CENTRAL, MEDLINE, Embase, AMED, CINAHL, ClinicalTrials.gov, and WHO ICTRP with no limitations. We checked the reference lists of included studies and relevant systematic reviews for studies.
Selection criteria
Randomised trials were included if the effect of splinting could be isolated from other treatment modalities. The comparisons included splinting versus no active treatment (or placebo), splinting versus another disease‐modifying non‐surgical treatment, and comparisons of different splint‐wearing regimens. We excluded studies comparing splinting with surgery or one splint design with another. We excluded participants if they had previously undergone surgical release.
Data collection and analysis
Review authors independently selected trials for inclusion, extracted data, assessed study risk of bias and the certainty in the body of evidence for primary outcomes using the GRADE approach, according to standard Cochrane methodology.
Main results
We included 29 trials randomising 1937 adults with CTS. The trials ranged from 21 to 234 participants, with mean ages between 42 and 60 years. The mean duration of CTS symptoms was seven weeks to five years. Eight studies with 523 hands compared splinting with no active intervention (no treatment, sham‐kinesiology tape or sham‐laser); 20 studies compared splinting (or splinting delivered along with another non‐surgical intervention) with another non‐surgical intervention; and three studies compared different splinting regimens (e.g. night‐time only versus full time).
Trials were generally at high risk of bias for one or more domains, including lack of blinding (all included studies) and lack of information about randomisation or allocation concealment in 23 studies.
For the primary comparison, splinting compared to no active treatment, splinting may provide little or no benefits in symptoms in the short term (< 3 months). The mean Boston Carpal Tunnel Questionnaire (BCTQ) Symptom Severity Scale (SSS) (scale 1 to 5, higher is worse; minimal clinically important difference (MCID) 1 point) was 0.37 points better with splint (95% confidence interval (CI) 0.82 better to 0.08 worse; 6 studies, 306 participants; low‐certainty evidence) compared with no active treatment. Removing studies with high or unclear risk of bias due to lack of randomisation or allocation concealment supported our conclusion of no important effect (mean difference (MD) 0.01 points worse with splint; 95% CI 0.20 better to 0.22 worse; 3 studies, 124 participants). In the long term (> 3 months), we are uncertain about the effect of splinting on symptoms (mean BCTQ SSS 0.64 better with splinting; 95% CI 1.2 better to 0.08 better; 2 studies, 144 participants; very low‐certainty evidence).
Splinting probably does not improve hand function in the short term and may not improve hand function in the long term. In the short term, the mean BCTQ Functional Status Scale (FSS) (1 to 5, higher is worse; MCID 0.7 points) was 0.24 points better (95% CI 0.44 better to 0.03 better; 6 studies, 306 participants; moderate‐certainty evidence) with splinting compared with no active treatment. In the long term, the mean BCTQ FSS was 0.25 points better (95% CI 0.68 better to 0.18 worse; 1 study, 34 participants; low‐certainty evidence) with splinting compared with no active treatment.
Night‐time splinting may result in a higher rate of overall improvement in the short term (risk ratio (RR) 3.86, 95% CI 2.29 to 6.51; 1 study, 80 participants; number needed to treat for an additional beneficial outcome (NNTB) 2, 95% CI 2 to 2; low‐certainty evidence).
We are uncertain if splinting decreases referral to surgery, RR 0.47 (95% CI 0.14 to 1.58; 3 studies, 243 participants; very low‐certainty evidence).
None of the trials reported health‐related quality of life.
Low‐certainty evidence from one study suggests that splinting may have a higher rate of adverse events, which were transient, but the 95% CIs included no effect. Seven of 40 participants (18%) reported adverse effects in the splinting group and 0 of 40 participants (0%) in the no active treatment group (RR 15.0, 95% CI 0.89 to 254.13; 1 study, 80 participants).
There was low‐ to moderate‐certainty evidence for the other comparisons: splinting may not provide additional benefits in symptoms or hand function when given together with corticosteroid injection (moderate‐certainty evidence) or with rehabilitation (low‐certainty evidence); nor when compared with corticosteroid (injection or oral; low certainty), exercises (low certainty), kinesiology taping (low certainty), rigid taping (low certainty), platelet‐rich plasma (moderate certainty), or extracorporeal shock wave treatment (moderate certainty). Splinting for 12 weeks may not be better than six weeks, but six months of splinting may be better than six weeks of splinting in improving symptoms and function (low‐certainty evidence).
Authors' conclusions
There is insufficient evidence to conclude whether splinting benefits people with CTS. Limited evidence does not exclude small improvements in CTS symptoms and hand function, but they may not be clinically important, and the clinical relevance of small differences with splinting is unclear. Low‐certainty evidence suggests that people may have a greater chance of experiencing overall improvement with night‐time splints than no treatment. As splinting is a relatively inexpensive intervention with no plausible long‐term harms, small effects could justify its use, particularly when patients are not interested in having surgery or injections.
It is unclear if a splint is optimally worn full time or at night‐time only and whether long‐term use is better than short‐term use, but low‐certainty evidence suggests that the benefits may manifest in the long term.
Tropical peatlands contain one of the largest pools of terrestrial organic carbon, amounting to about 89,000 teragrams (1 Tg is a billion kilograms). Approximately 65 per cent of this carbon store is ...in Indonesia, where extensive anthropogenic degradation in the form of deforestation, drainage and fire are converting it into a globally significant source of atmospheric carbon dioxide. Here we quantify the annual export of fluvial organic carbon from both intact peat swamp forest and peat swamp forest subject to past anthropogenic disturbance. We find that the total fluvial organic carbon flux from disturbed peat swamp forest is about 50 per cent larger than that from intact peat swamp forest. By carbon-14 dating of dissolved organic carbon (which makes up over 91 per cent of total organic carbon), we find that leaching of dissolved organic carbon from intact peat swamp forest is derived mainly from recent primary production (plant growth). In contrast, dissolved organic carbon from disturbed peat swamp forest consists mostly of much older (centuries to millennia) carbon from deep within the peat column. When we include the fluvial carbon loss term, which is often ignored, in the peatland carbon budget, we find that it increases the estimate of total carbon lost from the disturbed peatlands in our study by 22 per cent. We further estimate that since 1990 peatland disturbance has resulted in a 32 per cent increase in fluvial organic carbon flux from southeast Asia--an increase that is more than half of the entire annual fluvial organic carbon flux from all European peatlands. Our findings emphasize the need to quantify fluvial carbon losses in order to improve estimates of the impact of deforestation and drainage on tropical peatland carbon balances.
Tropical peat swamp forests (TPSFs) are found mainly in Southeast Asia and especially Indonesia. A total of 61% were lost between 1990 and 2015 and 6% remained in a pristine condition by 2015. ...Tropical peat swamps store vast amounts of carbon in their peat, but peat degradation, through drainage and fire, leads to high greenhouse gas emissions. This is gaining much international attention and, with it, policy initiatives and funding for restoration from local to landscape scales are being promoted. Unfortunately, although there is a now strong desire and need for TPSF restoration, methods are lacking. Ecological understanding is still at an early stage, and, even more so, in its applied use. There is an imbalance between the activities of TPSF restoration and sound ecological application. Furthermore, while many activities are underway and knowledge is being gained, these techniques are yet to be published. This article has been written to provide a common‐sense, practical guide to tropical peatland forest restoration which summarizes what we know to date, while acknowledging the gaps in our understanding. Topics covered include species selection, land assessment, land selection, and appropriate nursery, transplanting, and monitoring methods. The authors make no apologies that in places this reads like a manual as, given the importance of tropical peatland recovery and the recent attention and funding opportunities available, it is essential we now provide techniques to restoration practitioners working on the ground, and a basic common‐sense approach must be the starting point.
Tropical peatlands are a known source of methane (CH4) to the atmosphere, but their contribution to atmospheric CH4 is poorly constrained. Since the 1980s, extensive areas of the peatlands in ...Southeast Asia have experienced land‐cover change to smallholder agriculture and forest plantations. This land‐cover change generally involves lowering of groundwater level (GWL), as well as modification of vegetation type, both of which potentially influence CH4 emissions. We measured CH4 exchanges at the landscape scale using eddy covariance towers over two land‐cover types in tropical peatland in Sumatra, Indonesia: (a) a natural forest and (b) an Acacia crassicarpa plantation. Annual CH4 exchanges over the natural forest (9.1 ± 0.9 g CH4 m−2 year−1) were around twice as high as those of the Acacia plantation (4.7 ± 1.5 g CH4 m−2 year−1). Results highlight that tropical peatlands are significant CH4 sources, and probably have a greater impact on global atmospheric CH4 concentrations than previously thought. Observations showed a clear diurnal variation in CH4 exchange over the natural forest where the GWL was higher than 40 cm below the ground surface. The diurnal variation in CH4 exchanges was strongly correlated with associated changes in the canopy conductance to water vapor, photosynthetic photon flux density, vapor pressure deficit, and air temperature. The absence of a comparable diurnal pattern in CH4 exchange over the Acacia plantation may be the result of the GWL being consistently below the root zone. Our results, which are among the first eddy covariance CH4 exchange data reported for any tropical peatland, should help to reduce the uncertainty in the estimation of CH4 emissions from a globally important ecosystem, provide a more complete estimate of the impact of land‐cover change on tropical peat, and develop science‐based peatland management practices that help to minimize greenhouse gas emissions.
We measured methane exchanges at the landscape scale using eddy covariance towers over a natural forest and an Acacia crassicarpa plantation in tropical peatland in Sumatra, Indonesia. Groundwater level (GWL) controls diurnal and seasonal variability in methane emissions. Annual methane emissions over the natural forest were around twice as high as those of the Acacia plantation. Lower methane emissions over the Acacia plantation may be attributed to lower GWL. Results highlight that tropical peatlands are significant methane sources, and probably have a greater impact on global atmospheric methane concentrations than previously thought.
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