Impact of fire on vegetation, soil microbes and CH4 emission from a degraded tropical peatland

2020 ◽  
Author(s):  
Hasan Akhtar ◽  
Massimo Lupascu ◽  
Omkar S. Kulkarni ◽  
Aditya Bandla ◽  
Rahayu S. Sukri ◽  
...  
Keyword(s):  
Southeast Asia ◽  
Water Table ◽  
Vegetation Structure ◽  
High Throughput Sequencing ◽  
Microbial Community Composition ◽  
Tropical Peatland ◽  
Tropical Peatlands ◽  
Peat Profile ◽  
The Impact

<p>Over the past few decades, tropical peatlands in Southeast Asia have been heavily degraded for multiple land uses, mainly by employing drainage and fire. More importantly, the extent of these degraded areas, primarily covered with ferns and sedges, have increased to almost 10% of the total peatland area in Southeast Asia. In particular, the role of sedges in plant-mediated gas transport to the atmosphere has been recognized as a significant CH<sub>4</sub> pathway in northern peatlands, however, in the Tropics this is still unknown. Within this context, we adopted an integrated approach using on-site measurements (CH<sub>4</sub>, porewater physicochemical characteristics) with genomics to investigate the role of hydrology, vegetation structure, and microbiome on CH<sub>4</sub> emission from fire-degraded tropical peatland in Brunei.</p><p>          We found for the first time that in degraded tropical peatlands of Southeast Asia, sedges transported 70-80% of the total CH<sub>4</sub> emission and significantly varied with values ranging from 1.22±0.13 to 6.15±0.57 mg CH<sub>4</sub> m<sup>-2</sup> hr<sup>-1</sup>, during dry and wet period, respectively. This variation was mainly attributed to water table position along with changes in sedge cover and porewater properties, which created more optimal methanogenesis conditions. Total emissions via this process might increase in the future as the extent of degraded tropical peatlands expands due to more frequent fire episodes and flooding.</p><p>          Further, we used 16S rRNA high-throughput sequencing to investigate the microbiomes in peat profile (above and below water table) as well as rhizo-compartments (Rhizosphere, Rhizoplane, Endosphere) of sedges. We found that the peat profile as well as rhizo-compartments of sedge harboured a higher number of methanogenic archaea in the order Methanomicrobiales and Methanobacteriales, compared to non-burnt and bulk soil, which further explains our findings of higher CH<sub>4</sub> emission from degraded tropical peatland areas covered with sedges. These insights into the impact of fire on hydrology, vegetation structure, and microbial community composition on CH<sub>4</sub> emissions provide an important basis for future studies on CH<sub>4</sub> dynamics in degraded tropical peatland areas.</p>

scholarly journals Education and Disaster Vulnerability in Southeast Asia: Evidence and Policy Implications

2020 ◽  
Vol 12 (4) ◽  
pp. 1401 ◽  
Author(s):  
Roman Hoffmann ◽  
Daniela Blecha
Keyword(s):  
Southeast Asia ◽  
Best Practice ◽  
Universal Access ◽  
Social Resources ◽  
Policy Implications ◽  
Empirical Literature ◽  
High Quality Education ◽  
Disaster Vulnerability ◽  
The Impact

This article summarizes the growing theoretical and empirical literature on the impact of education on disaster vulnerability with a focus on Southeast Asia. Education and learning can take place in different environments in more or less formalized ways. They can influence disaster vulnerability as the capacity to anticipate, cope with, resist, and recover from natural hazard in direct and indirect ways. Directly, through education and learning, individuals acquire knowledge, abilities, skills and perceptions that allow them to effectively prepare for and cope with the consequences of disaster shocks. Indirectly, education gives individuals and households access to material, informational and social resources, which can help reducing disaster vulnerability. We highlight central concepts and terminologies and discuss the different theoretical mechanisms through which education may have an impact. Supportive empirical evidence is presented and discussed with a particular focus on the role of inclusiveness in education and challenges in achieving universal access to high-quality education. Based on situation analysis and best practice cases, policy implications are derived that can inform the design and implementation of education and learning-based disaster risk reduction efforts in the region.

scholarly journals The effectiveness of canal blocking for hydrological restoration in tropical peatland

2019 ◽  
Vol 276 ◽  
pp. 06003
Author(s):  
Sigit Sutikno ◽  
Besri Nasrul ◽  
Haris Gunawan ◽  
Rachmad Jayadi ◽  
Rinaldi ◽  
...  
Keyword(s):  
Water Table ◽  
Groundwater Level ◽  
Natural State ◽  
Tropical Peatland ◽  
Deep Wells ◽  
Peatland Restoration ◽  
The Republic ◽  
The Impact

The Peatland Restoration Agency of the Republic of Indonesia (BRG-RI), an agency that is mandated to restore 2 million hectares of degraded peatland by 2020, has developed a 3-R approach towards tackling the problem based on the program of rewetting, revegetation, and revitalization of livelihood for the peatlands restoration in Indonesia. The Rewetting program that aims to rehabilitate hydrologically a peatland to a near natural state is carried out by canal blocking, canal backfilling, and construction of deep wells. To know the progress of the restoration activities by BRG, it is very important to understand the effectiveness of canal blocking on rewetting of the tropical peatland. The effectiveness of canal blocking was investigated through the monitoring of groundwater level (GWL) fluctuation around the canal block. This study was carried out at a canal block that is located at the peatland of Sungai Tohor Village, Kepulauan Meranti Regency, Riau Province. For monitoring of GWL fluctuation as the impact of canal blocking, five dipwells were set at the peatland that are perpendicular to the canal with the distance of 20 m, 70 m, 120 m, 170 m, and 220 m respectively. The results of this study show that the impact of canal blocking could raise the water table in the peatland at the radius of about 170 m from the canal. The radius impact of the re-wetting might be bigger or smaller, that strongly depends on the hydrotopography situation of the area.

Root exudates compounds and microbial community composition regulates CH4 dynamics in fire degraded tropical peatland

2021 ◽  
Author(s):  
Massimo Lupascu ◽  
Hasan Akhtar ◽  
Aditya Bandla ◽  
Rahayu S Sukri ◽  
Sanjay Swarup
Keyword(s):  
Microbial Community ◽  
Community Composition ◽  
Plant Species ◽  
Root Exudates ◽  
Plant Root ◽  
Microbial Community Composition ◽  
Vegetation Composition ◽  
Tropical Peatland ◽  
Tropical Peatlands ◽  
Labile C

<p>Fires and drainage are common disturbance factors in tropical peatlands (TP) in Southeast Asia. These disturbances alter the hydrology, vegetation composition, and peat biogeochemistry; thereby affecting the microbiome where microbial communities reside<strong>. </strong>Studies from northern peatlands have well established the role of vegetation composition in regulating the labile C, in the form of plant root exudates, and microbial community composition affecting the peat decomposition; however, for tropics, it remains unexplored. Recent studies have also established how these fire-degraded TP areas become a hot spot of sedge-mediated CH<sub>4</sub> emission. To further our understanding of control mechanisms regulating CH<sub>4</sub> dynamics, we investigated the composition of plant root exudates (n=3 per plant species) from sedges (Scleria sumatrensis) and ferns (Blechnum indicum, Nephrolepis hirsutula), the most commonly occurring plant species at our fire-degraded tropical peatland site in Brunei, Northwest Borneo, as well as microbial community composition in plant (n=9 for S. sumatrensis, and B. indicum, and n=5 for N. hirsutula) rhizo-compartments (rhizosphere, rhizoplane, endosphere).</p><p>         Using a targeted analysis, we found that the root exudates compounds secreted from sedge (Scleria sumatrensis) and one species of fern (Blechnum indicum) were significantly different (p<0.05) and showed a similar ratio of 2:1 for sugars (glucose, fructose) and organic acids (acetate, formate, lactate, malate, oxalate, succinate, tartrate), which is in contrast to that secreted from trees in intact tropical peatlands (1:2). Further, using 16S rRNA gene amplicon sequencing, we found that the microbial community composition in rhizo-compartments of plant species showed significant differences (p<0.001). Interestingly, the sedge species harboured a relatively higher abundance of methanogens (Thermoplasmata) and lesser methanotrophs (Alphaproteobacteria, Gammaproteobacteria) across all three compartments compared to fern species, which further supports the higher sedge-mediated CH<sub>4</sub> emissions from fire-degraded TP.</p><p>            Our results provide fresh insights into the effects of post-fire vegetation composition in regulating the labile C and microbial community composition, and hence affecting CH<sub>4</sub> emissions from fire-degraded TP. Further, our results can form an important basis for future CH<sub>4</sub> dynamics studies as the emissions might increase with the expansion of degraded TPs as a consequence of frequent fire episodes and flooding</p>

scholarly journals Patron-Client Politics and Political Change in Southeast Asia

1972 ◽  
Vol 66 (1) ◽  
pp. 91-113 ◽  
Author(s):  
James C. Scott
Keyword(s):  
Southeast Asia ◽  
Political Action ◽  
Social Ties ◽  
Electoral Politics ◽  
Fiscal Policies ◽  
Social Changes ◽  
Role Of The State ◽  
The Impact ◽  
Dimensions Of Variation

The analysis presented here is an effort to elaborate the patron-client model of association, developed largely by anthropologists, and to demonstrate its applicability to political action in Southeast Asia. Inasmuch as patron-client structures are not unique to Southeast Asia but are much in evidence, particularly in Latin America, in Africa, and in less developed portions of Europe, the analysis may possibly have more general value for understanding politics in preindustrial societies. After defining the nature of patron-client ties and distinguishing them from other social ties, the paper discriminates among patron-client ties to establish the most important dimensions of variation, examines both the survival and transformations in patron-client links in Southeast Asia since colonialism and the impact of major social changes such as the growth of markets, the expanded role of the state, and the creation of local regimes. Finally, the paper shows how patron-client bonds interact with electoral politics to create distributive pressures which, in turn, often lead to inflationary fiscal policies and vulnerability of regimes to losses of revenue.

scholarly journals China’s Soft Power Diplomacy in Southeast Asia

2008 ◽  
Vol 26 (1) ◽  
pp. 22-49 ◽  
Author(s):  
Johannes Dragsbaek Schmidt
Keyword(s):  
Southeast Asia ◽  
Soft Power ◽  
Bilateral Trade ◽  
Economic Restructuring ◽  
Regional Security ◽  
Ethnic Chinese ◽  
Political Relations ◽  
Regime Types ◽  
The Impact

The paper analyses the new geo-political and geo-economic strategic relationship between China and Southeast Asia. Is Chinese soft power encroachment into Southeast Asia creating greater stability, does it jeopardize US interests and what is the impact on the regime-types, economic restructuring, and the state-civil society relationship? The paper is divided into four parts. The first explores the historical and especially the contemporary changes in China’s geo-economic bilateral relationship with Southeast Asia through its bilateral trade, the role of FDI, the role of the ethnic Chinese Diaspora, and other political and economic factors. The second focuses on China’s role in the new emerging geo-political relations on a multilateral scale through new regional security, military and politico-economic institutions. The third part contains a brief exposure of shifting US bilateral and multilateral interests in the region - both geo-economic and geo-political; however the bulk of this section is devoted to a comparison of the differences and similarities of US and Chinese approaches in Southeast Asia. Finally some concluding remarks are offered.

Pharmacist contributions in the treatment of diabetes mellitus in Southeast Asia: a narrative review

2020 ◽  
Vol 30 (6) ◽  
Author(s):  
Ayu Wulan Dwiputri ◽  
Liza Pristianty ◽  
Andi Hermansyah
Keyword(s):  
Diabetes Mellitus ◽  
Southeast Asia ◽  
Pharmacist Intervention ◽  
Narrative Review ◽  
Patient Counselling ◽  
Treatment Of Diabetes ◽  
Pharmacist Services ◽  
The Impact

AbstractBackgroundThe growing burden of diabetes mellitus (DM) in Southeast Asia puts pharmacists in the ideal position to provide management of DM. This narrative review aims to describe the evidence of pharmacist contribution in improving DM in Southeast Asia.ContentA literature search was conducted to identify relevant research articles published from 2010 to 2018 in four databases (Scopus, Pubmed, MEDLINE, and Springerlink) describing pharmacist roles and activities intended to improve management of DM in Southeast Asian countries. Results were synthesized narratively and divided into three main sections: (1) the role of pharmacist in DM management, (2) the impact of pharmacist role, and (3) the barriers to the implementation of services in DM management. A total of 16 studies were identified, of which ten studies mentioned services that were conducted exclusively by a pharmacist and the remaining collaborated with other health professionals. A number of pharmacist services were reported including prevention, dispensing, medication review, drug information services, patient counselling and education, monitoring, follow-up, and referral. Barriers related to individual, organizational, and public recognition were described.Summary and outlookThe Pharmacist can contribute to improve DM management in a variety of settings. Action research on pharmacist intervention in DM is recommended.

Effects of microtopography, root exudates analogues and temperature variation on CO2 and CH4 production from fire-degraded tropical peat

2021 ◽  
Author(s):  
Hasan Akhtar ◽  
Massimo Lupascu ◽  
Rahayu S. Sukri
Keyword(s):  
Southeast Asia ◽  
Temperature Variation ◽  
Water Saturation ◽  
Tropical Peatland ◽  
Diurnal Temperature ◽  
Tropical Peat ◽  
Tropical Peatlands ◽  
Labile C ◽  
Strong Source ◽  
Diurnal Temperature Variation

<p>Despite being an important terrestrial carbon (C) reserve, tropical peatlands (TP) have been heavily degraded through extensive drainage and fire, to an extent where degraded TP occupies one-tenth of the total peatland area in Southeast Asia (as in 2015). Consequently, repeated fires along with frequent flooding can alter the microtopography, vegetation composition as well as higher diurnal temperature variation due to open canopy, where each is known to influence C dynamics. However, assessing the importance of all these variables on-site can be challenging due to difficult site conditions; hence an incubation experiment approach may provide more useful insights in disentangling the complex interplay of these important variables in regulating GHG (CO<sub>2</sub> and CH<sub>4</sub>) production and emissions from fire-degraded tropical peatland areas. Therefore, we conducted an incubation study to investigate the interactions of microtopography (creating water-saturation conditions: mesic, flooded oxic, and anoxic), labile C inputs (in form of root exudate secretion from ferns and sedges), as well as on-site diurnal temperature variation in regulating CO<sub>2</sub> and CH<sub>4</sub> production from fire-degraded tropical peat.</p><p>            We found that CO<sub>2</sub> and CH<sub>4</sub> production significantly varied among treatments and were strongly regulated by microtopography, labile C inputs, and temperature variation. Mesic (oxic) treatments acted as a strong source of CO<sub>2</sub> (230.4 ± 29 µgCO<sub>2 </sub>g<sup>-1 </sup>hr<sup>-1</sup>) and mild sink for CH<sub>4</sub> (-5.6 ± 0.2 ngCH<sub>4 </sub>g<sup>-1 </sup>hr<sup>-1</sup>) compared to anoxic treatments acting as a mild source of CO<sub>2</sub> (61.3 ± 6.2 µgCO<sub>2 </sub>g<sup>-1 </sup>hr<sup>-1</sup>) and strong source of CH<sub>4 </sub>(591.9 ± 112.1 ngCH<sub>4 </sub>g<sup>-1 </sup>hr<sup>-1</sup>). The addition of labile C enhanced both the CO<sub>2</sub> and CH<sub>4</sub> production irrespective of the treatment conditions, whereas the effect of diurnal temperature variation was clearly pronounced in mesic (for CO<sub>2</sub>) and anoxic (for CH<sub>4</sub>) conditions. Q<sub>10</sub> values for both CO<sub>2</sub> and CH<sub>4</sub> production varied significantly with higher values for CO<sub>2</sub> in mesic treatments (1.21 ± 0.28) and higher for CH<sub>4</sub> in anoxic treatments (1.56 ± 0.35). We also observed a gradient across conditions, where flooded oxic treatments showed in-between values both for CO<sub>2</sub> and CH<sub>4</sub> production and temperature sensitivity, further reflecting the importance of on-site peat water-saturation in regulating the GHG production and emission from the fire degraded tropical peatland areas.</p><p>            Overall, these findings highlight how the water-saturation conditions due to microtopographic variation in peat surface, quality, and quantity of labile C secreted from plant communities and temperature variation during a day can influence the GHGs production rates from the fire degraded tropical peat. More importantly, given the current state and extent of degraded tropical peatland areas and future climate and land-use changes as well as frequent fire episodes in the region, our results demonstrate the increasing trend in GHG production from the fire-degraded tropical peatlands in Southeast Asia.</p>

scholarly journals Are Female Political Leaders Role Models? Lessons from Asia

2018 ◽  
Vol 71 (2) ◽  
pp. 255-269 ◽  
Author(s):  
Shan-Jan Sarah Liu
Keyword(s):  
Southeast Asia ◽  
Role Models ◽  
Role Model ◽  
Political Engagement ◽  
Descriptive Representation ◽  
Political Leaders ◽  
East And Southeast Asia ◽  
Female Legislators ◽  
The Impact

Despite vast research on women’s descriptive representation, little is known about its influence on women’s political engagement in East and Southeast Asia where gender norms are different from those in other parts of the world. I theorize that the discrepancy between women’s political and social rights in the region makes it difficult for women to envision themselves as equal to their male counterparts. Thus, women are less reluctant to play a “man’s game” even when they see female political leaders. Using a multilevel model with data from the Asian Barometer Survey and various additional sources, I examine the impact of female parliamentarians in the region and find that they significantly reduce women’s political participation. My results suggest that the female legislators’ role model effect found in existing literature on Western democracies does not apply to East and Southeast Asia. Instead, female political leaders generate a backlash effect on women’s political engagement. This research raises implications for the role of context in the effectiveness of women’s symbolic representation and calls for further exploration on the connection between women’s symbolic and descriptive representation.

scholarly journals Unravelling the virome in birch: RNA-Seq reveals a complex of known and novel viruses

2019 ◽  
Author(s):  
Artemis Rumbou ◽  
Thierry Candresse ◽  
Armelle Marais ◽  
Laurence Svanella-Dumas ◽  
Maria Landgraf ◽  
...  
Keyword(s):  
High Throughput Sequencing ◽  
De Novo ◽  
Leaf Roll ◽  
Viral Population ◽  
Comprehensive Overview ◽  
Dna And Rna ◽  
Birch Trees ◽  
Viral Communities ◽  
The Impact

AbstractHigh-throughput sequencing (HTS), combined with bioinformatics for de novo discovery and assembly of plant virus or viroid genome reads, has promoted the discovery of abundant novel DNA and RNA viruses and viroids. However, the elucidation of a viral population in a single plant is rarely reported. In five birch trees of German and Finnish origin exhibiting symptoms of birch leaf-roll disease (BRLD), we identified in total five viruses, among which three are novel. The number of identified virus variants in each transcriptome ranged from one to five. The novel species are genetically - fully or partially - characterized, they belong to the genera Carlavirus, Idaeovirus and Capillovirus and they are tentatively named birch carlavirus, birch idaeovirus, and birch capillovirus, respectively. The only virus systematically detected by HTS in symptomatic trees affected by the BRLD was the recently discovered birch leafroll-associated virus. The role of the new carlavirus in BLRD etiology seems at best weak, as it was detected only in one of three symptomatic trees. Continuing studies have to clarify the impact of the carlavirus to the BLRD. The role of the Capillovirus and the Idaeovirus within the BLRD complex and whether they influence plant vitality need to be investigated. Our study reveals the viral population in single birch trees and provides a comprehensive overview for the diversities of the viral communities they harbor.

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