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In northern Laos, shortened fallows in the slash-and-burn upland rice system are not sustainable either from a production or economic standpoint. This paper evaluates the potential for using the indigenous fast-growing tree, Broussonetia papyrifera L. Vent. (paper mulberry) as an economic fallow crop. The objectives of this study are to assess the inner bark yield of paper mulberry, and to evaluate rice productivity following paper mulberry cultivation. In addition, allometric models for estimating the inner bark yield of paper mulberry are developed. Inner bark yield of paper mulberry stands ranging in age from 9 to 48 months ranged from 10 to 208 g m−2, and increased with age. The models using diameter at breast height and stem height, or diameter at breast height only as independent variables explained well the variation in inner bark yield. When paper mulberry was completely removed during the rice growing season, rice yields in these areas were similar to those following weedy bush fallow. When paper mulberry was allowed to grow, rice yields were negatively correlated to paper mulberry stem density. When paper mulberry lateral branches were pruned back, rice yields could be maintained if the paper mulberry stem density was <0.22 stems m−2, suggesting that if paper mulberry is managed properly, rice yields can be maintained at current levels. The paper mulberry-upland rice rotation system improves the productivity of a traditional slash-and-burn system through harvesting paper mulberry inner bark; however the long-term sustainability of such a system remains unclear and warrants further investigation. [ABSTRACT FROM AUTHOR]

Although participatory supply chain analysis (PSCA) is widely used to trigger action in development aid, there is very little published describing the method, its benefits and limitations. The theoretical background of participatory processes related to supply chain analysis and the related benefits and limitations found while implementing the method in Laos are presented. It is concluded that joint problem-solving in supply chains can be facilitated through PSCA as the method allows participants to evaluate their initial assumptions, investigate institutional barriers, gather new information and realise some of the interdependencies among supply chain participants. On the other hand, the lack of legitimate representatives, the failure to convince important stakeholders to participate, distances between participants, the length and breadth of the supply chain were factors limiting joint action. This method is recommended to study supply chains of niche products and local/regional products locally processed. [ABSTRACT FROM AUTHOR]

This study examines sustainable development cooperation and the effectiveness of sustainable development partnerships in supporting national development in meeting Sustainable Development Goals (SDGs). This study focuses on SDG 17, "Building Partnerships for Sustainable Development" and takes the Lao Democratic People's Republic (Laos) as its case study. The study assesses Laos's socio-economic condition, development trajectory and SDGs. It evaluates Laos's development partnerships with China and the Belt and Road Initiative (BRI) and wider development diplomacy. The study adopts a political economy perspective, drawing in global major power competition. The paper argues that development partnerships are pivotal to success in achieving national and global development goals. Laos holds the ASEAN Chair through 2024, whilst experiencing severe economic challenges domestically. Moving between these two domains, Laos will seek to achieve balance and even-handedness between regional and global interests. Laos's long-standing development partnership with China and the BRI brings tangible results. However, the study concludes that greater diversification in building partnerships for development will provide additional support to Laos's development strategy. [ABSTRACT FROM AUTHOR]

The enhancement of horizontal boundaries of potential field sources is of great significance for the study of geological structures. Most of the existing filters for horizontal edges enhancement are presented based on the derivatives of potential field data, but these filters often show some shortcomings, for example, the output edges are divergent, strong and weak anomalies cannot be balanced, or some extra false edges appear in the results. In this paper, the edges enhancement filter MMA based on mathematical morphology is first defined by the combination of the basic operators of mathematical morphology. In order to make the filter have the ability to balance different amplitude anomalies, MMAZ and MMAT are proposed, and both of them can be used to delineate the horizontal edges of the field sources by their maxima. The experimental results of synthetic data show that MMAZ and MMAT have good equalization and anti-noise performances. Compared with several traditional filters, the horizontal edges of geological bodies obtained by these two filters are clearer and more convergent, and there are no extra edges in the output results for the complex situations that positive and negative anomalies exist simultaneously. Finally, the two new equalization filters are applied to gravity anomaly data in a potash mine area in Vientiane basin of Laos and the aeromagnetic anomaly of a metal mine in northwest China, the obtained positions of the structures are more accurate and clearer, which further illustrates the effectiveness of the two filtering techniques. [ABSTRACT FROM AUTHOR]

This paper looks at how local livelihoods and to a certain extent their transitions are embedded in, and in thrall to, power relations at higher levels. Placing the (re)shaping of livelihood pathways within the context of top-down hydropower planning, it shows how the latter predetermines farm households' current farming strategies and future livelihood pathways. Taking two villages along the Mekong River, both of which are to be impacted by the planned Pak Beng hydropower dam in Pak Beng district, Oudomxay province, the paper illustrates how the pathways that rural livelihoods are taking in northern Laos are being shaped by decisions and processes embedded in national and regional exigencies. We argue that top-down approaches in hydropower planning, as manifested in the current institutional vacuum to formally deal with resettlement and compensation issues at the village level result in village authorities' and potentially affected villagers' inability to strategically convey and negotiate their views and concerns. Moreover, we reveal how it is the specter of change which drives livelihood adaptation, not change itself, thus illustrating how the defined compensation rules and procedures (re)shape farm households' farming strategies and future livelihood pathways even prior to the construction of the hydropower dam. [ABSTRACT FROM AUTHOR]

This paper presents the assessment of the distribution and characteristics of 137Cs activity in surface soil in the middle of Laos. Measurement has been conducted for 212 soil samples distributed evenly in the middle of Laos using low background gamma spectrometers. It is found that the activity concentrations of 137Cs vary in the range of 0.50–7.97 Bq kg−1 with the average value of 1.46 ± 0.21 Bq kg−1. The values agree well with those reported for neighboring regions and are significantly lower than the world average value. Higher activity concentrations of 137Cs were observed in geological formations with claystone, siltstone, and mud. Foothills were found with higher concentrations of 137Cs, while lower 137Cs concentrations were observed in low-altitude plains. No significant variation of the 137Cs activity concentration with terrain elevation was found. [ABSTRACT FROM AUTHOR]

Wind energy has become more prominent with contributions to CO2 emission reduction, energy prices, and climate change issues. High-resolution wind energy potential maps of the Mekong riverside area in the upper northeastern part of Thailand at elevations of 100, 120, and 200 m above sea level (ASL) are presented in this paper, made using coupled mesoscale and microscale atmospheric wind flow modeling. Wind resource maps are presented and validated with observed wind data from three wind measurement towers installed along the Mekong riverside. Wind resource maps at an elevation of 120 m (ASL) show that the northern region near Laos is characterized by wind speeds in the range of 1.29 to 3.79 m/s, while the mountainous area in Mukdahan has wind speeds in the range of 1.63 to 3.85 m/s. As stipulated in Thai energy policies for wind power plant development, the annual energy production, the capacity factors, and the reduction of CO2 gas emissions are analyzed for wind power plants generated by 2.5-, 3.3-, and 4.5-MW wind turbine generators. Results show a high potential for energy production in Mukdahan province, with a 2.5-MW wind turbine generating 62,315 MWh/year for a very small power producer (VSPP) wind power plant. Under the small power producer (SPP) condition, a plant could produce 68,454 MWh/year along with 16% of capacity factors. Eventually, the CO2 emission gases are reduced by approximately 4915 tons of CO2 emission/year for the VSPP plant, while the SPP plant could reduce them by 24,575 tons of CO2 emission/year. [ABSTRACT FROM AUTHOR]

Balancing agendas for climate mitigation and environmental justice continues to be one of the key challenges in climate change governance mechanisms, such as Reducing Emissions from Deforestation and Degradation (REDD+). In this paper we apply the three-dimensional environmental justice framework as a lens to examine the REDD+ process in the Lao People's Democratic Republic (Laos) and the REDD+ social safeguards. We focus particularly on challenges to justice faced by marginalized communities living in forest frontier areas under an authoritarian regime. Drawing on policy analysis and open-ended interviews across different policy levels, we explore procedural, distributional, and recognitional justice across the REDD+ policy levels in Laos. We find that REDD+ social safeguards have been applied by both donors and state actors in ways that facilitate external control. We underscore how authoritarian regime control over civil society and ethnic minority groups thwarts justice. We also highlight how this political culture and lack of inclusiveness are used by donors and project managers to implement their projects with little political debate. Further obstacles to justice relate to limitations inherent in the REDD+ instrument, including tight schedules for dealing with highly sensitive socio-political issues under social safeguards. These findings echo other research but go further in questioning the adequacy of safeguards to promote justice under a nationally driven REDD+. We highlight the importance of recognition and political context, including aspects such as power relations, self-determination and self-governance of traditional or customary structures, in shaping justice outcomes. [ABSTRACT FROM AUTHOR]

The high-content salt rock stratum is a highly water-soluble, corrosive, and expansive stratum, and it is extremely difficult to construct tunnels in the stratum. The China-Laos cross-border railway friendship tunnel, which traverses the high-content salt rock stratum, sustained extremely serious damage during the construction. Therefore, studying the mechanisms by which the salt rock stratum tunnels are damaged is the key to ensuring the long-term service of the tunnel. In this paper, a comprehensive method system was used, such as on-site exploration, laboratory tests, and theoretical analysis, to identify the mechanisms by which the tunnels are damaged in the high-content salt rock stratum. Research has indicated that the main component of the rocks that surround the tunnel in the salt rock stratum is rock salt (NaCl and Na2SO4). Excavation in the salt rock stratum is prone to various catastrophes, such as the precipitation of salt crystals on the lining surface, the formation of a cavity at the bottom of the tunnel, cracking of the concrete lining, bulging and cracking of the inverted arch, and serious corrosion of the steel structure. Tunnels in salt rock stratum will undergo physical erosion and physicochemical erosion of the concrete lining in a water environment, and the precipitation of salt crystals and expansion will eventually damage the lining of the structure. Also, due to the accelerated corrosion effect of water and salt on the structure of the lining, cavities occur in the lining in a short time, and this results in a decrease of the bearing capacity. [ABSTRACT FROM AUTHOR]

The Golden Triangle—the area where the borders of Thailand, Laos, and Myanmar converge—is considered one of the most complicated narcotics-trafficking hotspots in the world. More research is needed, however, to understand the supply and demand resources as well as the overall structure of transnational narcotics trafficking (TransNT) in this area and neighboring regions. The present paper provides an in-depth examination of the organisational structure of TransNT in the borderland between Vietnam and Laos, using multiple qualitative approaches to identify four key aspects of trafficking groups in this area: namely, group size, the relative centrality of lead actors in the trafficking networks, the flexibility and adaptability of network operations, and the personal attributes of traffickers. Depending on the number of drug traffickers involved, TransNT in Vietnam can be separated into small, medium, and large-scale groups; however, drug markets in Vietnam are not controlled by monopolistic groups or 'cartels'. Notably, cross-border networks tend to have a fluid structure characterised by a sophisticated modus operandi from the preparation stages to the later stages of trafficking activity, enabling the criminal networks to achieve their goals. [ABSTRACT FROM AUTHOR]

Laos is a mountainous, rainy and less developed country in Southeast Asia. In Laos, floods represent a major constraint on social economic development, causing a large number of casualties and property losses each year, among which the impact from flash floods is also very prominent. Especially in recent decades, with the development of social economy and the intensification of hydropower development, the serious threat from flash floods is becoming more and more obvious. However, there is no fundamental defence system for flash floods been established yet in this country, and the basic knowledge on local flash flood development is also ignored. For filling this gap, taking the Nam Ou River Basin as an example, this paper tries to find out the most helpful hazard assessment method for current Laos based on comparative analysis from the flash flood potential index, the calculation of curve number–rainfall erosivity and the extrapolation method. The results show that the extrapolation method based on spatial lag model constructed by the data from Yunnan, China, presents the most reliable outcome compared with the other two methods, indicating the spatial autocorrelation model can also be useful for extrapolation, effectively. Besides, the scale effect of different potential impact elements on flash flood, i.e. the spatial correlation between each element and the distribution of flash flood events at different spatial statistic units, was also preliminary studied. It is found that the degree of correlation in spatial analysis depends on the short board effect, i.e. only the element that restricts the regional flash flood developmental system can be the key factor. The correlations of most watershed elements increase or decrease directly with the rise of watershed scale, and the values of coefficients tend to be stable at large watershed scales. [ABSTRACT FROM AUTHOR]

The social relations and biophysical flows that link water, food, and energy systems are said to form a 'nexus'. Efforts to steer or otherwise exert influence on decisions that impact upon these nexus links, including to ignore them, take place at multiple levels, vary in complexity, and have implications for who benefits and who is burdened by those relations and flows. This paper examines how nexus links have been governed, using four medium- to large-scale water infrastructure projects in Laos and Thailand as probes into problematic issues of coordination, anticipation, inclusion, and attribution. Project documents, media reports, and published analyses were coded to extract information about nexus links, narratives, and decisions. Nexus interactions were summarized using a novel symbolic notation and then classified along a scale of increasing structural complexity as pairs, chains, and loops. The key finding from the analysis of the four projects was that nexus governance was fragmented, reactive, exclusive, and opaque. Coordination among ministries was limited with inter-ministerial bodies, and integrated development plans ineffective at guiding project design or operation decisions in the presence of bureaucratic competition. Anticipation of cross-sectoral concerns was rare, despite scope to identify them early in feasibility studies, and assessment activities; instead they were only acknowledged after public pressure. Inclusion of the needs of vulnerable and affected groups was limited, although poverty alleviation, and other social benefits were a significant element in project justification narratives. Attribution of responsibility was difficult as many key decisions took place behind closed doors, while project information was withheld, raising further governance issues of transparency and accountability. Structural complexity in the nexus links made addressing governance problems even more challenging. [ABSTRACT FROM AUTHOR]

This paper presents the evaluation of natural radioactivity and radiological hazards of the terrestrial naturally occurring radionuclides of 226 Ra , 232 Th and 40 K in Savannakhet province, Laos. The activity concentrations of 226 Ra , 232 Th and 40 K are in the range of 6.6–73.6, 3.8–113.8 and 13.6–906.4 Bq kg - 1 , with the average values of 22.4 ± 2.1 , 30.8 ± 2.9 and 211.6 ± 16.5 Bq kg - 1 , respectively. The average radium equivalent activity Ra eq is calculated as 82.8 ± 9.7 Bq kg - 1 , which is smaller than the safety limit of 370 Bq kg - 1 . Radiological hazard indices have also been evaluated in comparison with the world average values. [ABSTRACT FROM AUTHOR]

Despite being a low-income, agriculture-based country with a subsistence orientation, Laos is in the early stages of a major economic transformation whereby rural households have been experiencing rapid change in their farming and livelihood systems. Some households have begun to engage in semi-commercial farming while others have adopted labour-oriented or migration-oriented livelihood strategies. This paper explores how rural households in six villages in the lowlands of Champasak Province in southern Laos make a living. These villages vary in their access to irrigation and to markets. Nevertheless, in all villages, long-term migration of younger household members to neighbouring Thailand has come to play a large role in household livelihood strategies. In some cases this is necessary to meet the household's consumption requirements; in most, it is part of a diversified strategy in which rice farming still plays a significant role, though still largely for subsistence. The paper examines some of the issues involved in attempting to promote intensive, market-oriented rice farming in a context of an emerging on-farm labour shortage combined with an increasing flow of remittances from migrant family members. [ABSTRACT FROM AUTHOR]

In the Xi Jinping era, China is actively implementing the Belt and Road Initiative (BRI) around the globe. Under the BRI, infrastructure development has become the main agenda for China to create connectivity. One of the infrastructure projects in the energy sector is the Nam Ou Cascade Hydropower Project. The Nam Ou River is a tributary of the Mekong River located in Laos and borders China. For Laos, this project is part of their vision to be "The battery of Southeast Asia." Therefore, this article attempts to explain that Nam Ou Hydropower has implications for China's dominance in the Mekong region. The circle hydro-hegemony is used as the conceptual framework for analyzing the phenomenon. This article also applies a qualitative method with secondary data. The article shows that the Nam Ou Cascade Hydropower Project in Laos elevates China's influence in the Mekong region. By actively pulling and pushing its neighbors into cooperation, China exercises its power as an upstream country. [ABSTRACT FROM AUTHOR]

Scaling out and up are terms increasingly being used to describe a desired expansion of beneficial impacts from agricultural research and rural development. This paper explores strategies for scaling out production and livelihood impacts from proven technologies. We draw on a case study of forages and livestock production in Laos, a Southeast Asian country undergoing rapid economic and agricultural change. A facilitated learning environment stimulated farmers to adapt forages, livestock housing, and animal health practices to their own situations (scaling out). Regular follow-up visits and on-the-job mentoring for extension staff provided institutional support (scaling up). Within 5 years, the number of villages and households using forages and fattening livestock had increased six fold, with a 50% reduction in the time required for farmers to get significant benefits. The paper concludes that scaling out positive impacts from systems change requires field tested and proven technologies, evidence of significant livelihood impacts, fostering of local innovation, competent field staff, effective peer learning, and ongoing institutional support. [ABSTRACT FROM AUTHOR]

Secure environmental contexts are crucial for hominin interpretation and comparison. The discovery of a Denisovan individual and associated fauna at Tam Ngu Hao 2 (Cobra) Cave, Laos, dating back to 164–131 ka, allows for environmental comparisons between this (sub)tropical site and the Palearctic Denisovan sites of Denisova Cave (Russia) and Baishiya Karst Cave (China). Denisovans from northern latitudes foraged in a mix of forested and open landscapes, including tundra and steppe. Using stable isotope values from the Cobra Cave assemblage, we demonstrate that, despite the presence of nearby canopy forests, the Denisovan individual from Cobra Cave primarily consumed plants and/or animals from open forests and savannah. Using faunal evidence and proxy indicators of climates, results herein highlight a local expansion of rainforest at ~ 130 ka, raising questions about how Denisovans responded to this local climate change. Comparing the diet and habitat of the archaic hominin from Cobra Cave with those of early Homo sapiens from Tam Pà Ling Cave (46–43 ka), Laos, it appears that only our species was able to exploit rainforest resources. [ABSTRACT FROM AUTHOR]

The whitefly genus, Indoaleyrodes David and Subramaniam is reported for the first time from Japan with description of Indoaleyrodes japonica sp. nov. Indoaleyrodes geminata Pushpa and Sundararaj syn. nov. and I. strychnosae Pushpa and Sundararaj syn. nov. are synonymized with I. laos (Takahashi) through examination of holotype. Puparia of the new species are causing leaf pit-galls in leaves of Eurya japonica (Pentaphylacaceae) in Shizuoka, Japan. Ecological information on the new species and leaf gall forming whiteflies is given. Line drawings, images of holotype and habitus, and an identification key to puparia of Indoaleyrodes species so far described are provided. [ABSTRACT FROM AUTHOR]

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Declining biodiversity in protected areas in Laos is attributed to unsustainable exploitation of natural resources. At a basic level, an important need is to develop capacity in academic and professional training institutions to provide relevant training to conservation professionals. The paper (a) describes the capacity building approach undertaken to achieve this goal, (b) evaluates the effectiveness of the approach in building capacity for implementing conservation and (c) reviews implementation outcomes. Strong linkages between organizations implementing field conservation, professional training institutions, and relevant Government agencies are central to enhancing effectiveness of capacity building initiatives aimed at improving the practice of conservation. Protected area management technical capacity needs will need to directly influence curriculum design to insure both relevance and effectiveness of training in improving protected area management. Sustainability of capacity building initiatives is largely dependent on the level of interest and commitment by host-country institutions within a supportive Government policy framework in addition to engagement of organizations implementing conservation. [ABSTRACT FROM AUTHOR]

This paper presents results from a year-long household survey in which the aquatic resource collection and consumption activities of 240 households across Lao PDR were studied to assess the diversity of species used, their role in household food security and the overall importance of ricefield habitats in this respect. Results show that aquatic biodiversity, under threat in rice-based ecosystems, plays a larger role in household consumption than previous estimates. More than 90 % of these resources are collected by households themselves and the greatest quantities from ricefield habitats. This seasonal aquatic environment is therefore the principal habitat from which households acquire aquatic animals, both to eat fresh and to process and store for use during nutritionally vulnerable times of year. The importance of these habitats therefore goes far beyond their use for rice production and this multi-functionality needs to be understood and addressed in agricultural, conservation and food security policy. [ABSTRACT FROM AUTHOR]

Despite the rapid agricultural transition that has occurred in the past decade, shifting cultivation remains a widespread agricultural practice in the northern uplands of Lao PDR. Little information is available on the basic socio-economic situation and respective possible patterns in shifting cultivation landscapes on a regional level. On the basis of a recent approximation of the extent of shifting cultivation landscapes for two time periods and disaggregated village level census data, this paper characterizes these landscapes in terms of key socioeconomic parameters for the whole of northern Laos. Results showed that over 550,000 people live in shifting cultivation regions. The poverty rate of this population of 46.5 % is considerably higher than the national rural rate. Most shifting cultivation landscapes are located in remote locations and a high share of the population comprises ethnic minorities, pointing to multi-dimensional marginality of these areas. We discuss whether economic growth and increased market accessibility are sufficient to lift these landscapes out of poverty. [ABSTRACT FROM AUTHOR]

This paper explores associations between the returns from harvesting a commercial non-timber forest product and particular characteristics of harvesters and their strategies. Data originate from a survey in Laos of the harvest and trade of agarwood, a highly valuable commodity harvested mainly from tree species in the genus Aquilaria. Five groups of harvesters were identified, with considerable differences in returns between them. Foreign harvesters, i.e., ethnic Vietnamese, earned approximately USD 13 per day on average, while nonlocal full-time harvesters earned approximately USD 9, and nonlocal part-time harvesters USD 7 per day. Local people earn approximately USD 5 per day and only USD 4 if harvesting only took place in village forests. Factors observed to determine returns are market access, especially access to national and international markets, and knowledge and experience in trading, harvesting, and the organization of harvesting trips, It is suggested that interventions should be made to address these factors, to level out returns from harvesting, and to increase the share of returns captured by local people. [ABSTRACT FROM AUTHOR]

Enhancement of inland fisheries through stocking can potentially increase fisheries production in developing countries and improve rural livelihoods. However, results of stocking are often unexpected in terms of benefit distribution. Taking an environmental entitlements approach, this paper details the nature and extent of institutional change that accompanied stocking in Savannakhet Province, Lao PDR, and quantifies its impact on households from different socioeconomic groups. Stocking was a catalyst significantly affecting people’s command over living aquatic resources. New rules changed who could go fishing for what and when, and how the fish could be utilized. Customary rights were transformed and decision-making power concentrated. Despite this, household surveys demonstrated that no socioeconomic group was benefiting disproportionately and this was due to the specific social, political and institutional context into which enhancement was placed. However, in different contexts, increased benefits for resource users, even in cases of increased fisheries production, cannot be assumed. [ABSTRACT FROM AUTHOR]

In northern Laos, upland rice is grown as a subsistence crop under rainfed conditions with no fertilizer inputs. It has traditionally been grown under slash-and-burn systems with long fallows, which restore soil fertility and reduce insect and weed pressure. However, increasing population density and government policies aimed at reducing the area under slash-and-burn have reduced fallows to as little as two or three years between rice crops. In this paper the impact of intensifying upland rice cultivation and rainfall on upland rice productivity was evaluated using yield and rainfall data from Luang Prabang province from 1992 to 2004. In addition, an experiment was conducted in 2004 to evaluate the effect of upland rice cropping intensification on soil nitrogen (N) and phosphate (P) availability and root pests ( Tetraneura nigriabdominalis-root aphids and Meloidogyne graminicola Golden & Birchfield-nematodes). Rice yields were associated with total rainfall from June through August, corresponding to mid-tillering through flowering growth stages of upland rice. Increased cropping intensity resulted in a significant reduction of upland rice yields with higher rice yields being associated with longer fallows. Furthermore, when rice was annually cropped in the same field without fallows, rice yields rapidly declined. A study conducted in 2004 indicated that increasing cropping intensity reduced the soil N and P availability and increased root aphid infection of rice. The long-term productivity of upland rice can not be sustained with increased cropping intensity using the current management practices. Therefore, improved crop and resource management technologies are necessary for sustainable production. [ABSTRACT FROM AUTHOR]

This paper reports a study of paddy vegetation in central Laos. Plants were inventoried and vegetation types classified. Relationships between vegetation and agricultural practices were identified. A total of 184 wild herbaceous species and 17 cultivated species were recorded in two villages. Of the wild species, 19 were used by local people, four were rare species, and three were major weeds. Paddy vegetation was arranged in order of water regime from shorter to longer hydroperiod by DCA. The factors contributing to high species diversity were: (1) the presence of species unique to different paddy types; (2) the presence of remnant species from original vegetation; and (3) the impact of agricultural practices. Thus, at this study site, multiple plant species coexisted in paddy fields under various agricultural practices, and some species were essential sources of food or were used in other ways to support the subsistence livelihoods of local residents. [ABSTRACT FROM AUTHOR]

This paper examines how a biodiversity monitoring system based on data collected by protected area staff and local communities was established and maintained in Xe Pian national protected area, Laos. Monitoring activities commenced with project support in 1998. Protected area staff, district forestry staff and villagers continued the monitoring work after 2001 when the external advisers left. More than 2500 records of wildlife, natural resource use and threats to the protected area were collected by villagers and protected area staff, mainly through use of patrols, village discussions and village logbooks. The management interventions that followed the monitoring activities were a reaction to immediate threats or perceived trends in biodiversity rather than to trends revealed by analyses of the collected data. Patrols and village discussions came to a virtual standstill when external funding ceased, probably because of lack of supporting national policies. The annual running cost of the monitoring system was only about US$ 4000 or 0.02 per ha of forest habitat. [ABSTRACT FROM AUTHOR]

Mismanaged plastic waste is a significant contributor to microplastic pollution in the environment, which can cause riverine pollution problems, adverse ecological effects, and pose risks to human health. In this context, extensive research has been conducted on microplastics (MPs) contamination in surface water in urban water environments. This work detected the abundance and characteristics of MPs in urban canals and sub-river (Mark-Hiao River) in the Vientiane capital. Additionally, the hazard risk to the ecological system posed by MPs was analyzed using calculated risk index values. The results showed that the abundance of MPs in the dry and rainy seasons ranged from 0.38 to 4.61 items/m3 and 1.23 to 7.10 items/m3, respectively. Among them, the most commonly found microplastic polymer types in the water samples were polypropylene (PP) > polyethylene (PE) > polystyrene > polyethylene terephthalate (PET) > nylon > other plastic. The diverse composition of MPs along the canals and Mark-Hiao River indicated medium and low hazard levels. However, it is necessary to take action to mitigate and manage the potential risks caused by microplastic pollution, ensuring the preservation of urban aquatic environment for future generations. Strategies recommended encompass promoting publicity and education, implementing green consumption practices, formulating and efficiently implementing regulations, improving the efficiency of wastewater treatment plant, encouraging the use of biodegradable plastics, refusing single-use and non-degradable plastics, and setting a monitoring standard. [ABSTRACT FROM AUTHOR]

The timing of the first arrival of Homo sapiens in East Asia from Africa and the degree to which they interbred with or replaced local archaic populations is controversial. Previous discoveries from Tam Pà Ling cave (Laos) identified H. sapiens in Southeast Asia by at least 46 kyr. We report on a recently discovered frontal bone (TPL 6) and tibial fragment (TPL 7) found in the deepest layers of TPL. Bayesian modeling of luminescence dating of sediments and U-series and combined U-series-ESR dating of mammalian teeth reveals a depositional sequence spanning ~86 kyr. TPL 6 confirms the presence of H. sapiens by 70 ± 3 kyr, and TPL 7 extends this range to 77 ± 9 kyr, supporting an early dispersal of H. sapiens into Southeast Asia. Geometric morphometric analyses of TPL 6 suggest descent from a gracile immigrant population rather than evolution from or admixture with local archaic populations. Here the authors report new human fossils from Tam Pà Ling cave, Laos, consisting of a cranial and a tibial fragment, dated to 68–86 thousand years ago. This find confirms that Homo sapiens were present in Southeast Asia by this time and the shape of the fossils indicates they may have descended from non-local populations. [ABSTRACT FROM AUTHOR]

We report here the yielding behavior and large amplitude oscillatory shear (LAOS) response of dense colloidal suspensions of two types of thermo-responsive poly(N-isopropylacrylamide) (PNIPAM) microgel spherical particles: (i) having core–shell (CS-PNIPAM) structure with dangling polymer chains and (ii) having only a homogeneous cross-linked core (HC-PNIPAM). By performing systematic rheological studies on the glassy state of these two types of colloidal particles, we show that dangling polymer chains that exist on CS-PNIPAM particles exhibit two-step yielding analogous to that reported in soft-sphere colloidal glasses with attractive interactions, whereas the dense suspensions of HC-PNIPAM spheres, in which dangling polymer chains are absent, showed single-step yielding similar to that of hard-sphere colloidal glasses. Dynamic light scattering measurements on CS-PNIPAM clearly show that dangling polymer chains, which are absent in HC-PNIPAM particles, get entangled under dense conditions and are responsible for (i) observed sub-diffusive behavior in mean squared displacement at small time and (ii) two-step yielding behavior in dense colloidal glass of CS-PNIPAM spheres. Further, we did LAOS measurements to gain further insight on the role of dangling polymer chains and their entanglements on the yielding behavior of the glassy state. We determined the energy associated with the yielding in the glassy state of both types of microgel particles and interpret its role in disentangling the dangling polymer chains between the CS-PNIPAM particles in their dense state as well as its contribution to the cage breaking under shear in the glassy state. [ABSTRACT FROM AUTHOR]

Laos is among the top twenty coffee producing country in the world—producing about 39,000 tonnes per year—and most of its production is currently exported to over 26 countries, contributing about 1.1% of the total export value or US$64.3 million in 2019 to Laos' national economy. COVID-19 restrictions on trade and movement of people have largely impacted on coffee markets and production. As a strategic crop in Laos, it is supported by a range of policies and programs to generate greater benefits to both independent smallholder farmers and those involved in cooperatives, including support for agroforestry production models involving coffee and tree crops. However, studies of the profitability of different coffee agroforestry models are limited. This study compares financial returns from four most popular coffee agroforestry models in two coffee production provinces of Laos, before and during COVID-19 pandemic. The data were gathered from 20 farmers, five coffee traders and an integrated coffee processing company. These data were then triangulated with, and supplemented by, interviews with coffee exporters (n = 3) and key informants (n = 4). Financial indicators suggest that all four agroforestry models were profitable before COVID, but profits for cooperative growers were higher than for smallholders due to higher crop productivity and lower costs. Despite higher prices due to COVID restrictions, other factors reduced profitability of all four models and one smallholder model became unprofitable. The reasons for such differences and related policy implications are discussed. [ABSTRACT FROM AUTHOR]

Rice is a staple meal for the majority of Asians. However, human exposure to polycyclic aromatic hydrocarbons from paddy grain is largely unknown in Thailand and Laos. Therefore, information on the quantitative measurement and assessment of the health problems caused by PAHs was analyzed. The results showed that the concentrations of total PAHs in paddy grain in Thailand and Laos were 38.86 ± 5.13 and 11.35 ± 1.96 ng g−1, respectively. The highest concentration of PAHs in Thailand was B[k]F, whereas D[a,h]A was found to be the highest in Laos. A p-value less than 0.05 was defined, which showed B[b]F and B[k]F from Thailand and Laos were significant, which indicated that they could be from a different pollutant source. The main finding of this study, which was supported by the diagnostic ratios of PAHs and HCA, was that the primary source of PAHs was assumed to be incomplete combustion of petroleum products, which was caused by the burning of industrial fuels or vehicle exhausts, as well as open burning. The findings suggest that these two nations have similar PAH origins. Agricultural waste burning and transportation emissions are well-known sources of PAHs in Thailand and Laos. The cancer risk assessment method was based on the accumulation of PAHs from paddy grains. An ILCR of 1.0E-06 to 1.0E-04 was considered a tolerable limit of cancer risk, while a risk > 1.0E-04 was considered a concern in terms of cancer risk. The findings indicated that while PAH emissions exist, their contribution to global toxicity may be anticipated to be low in inhalation exposure. The higher values of ingestion and dermal risk estimated were regarded as the tolerable limit of cancer risk in children and adults from both countries, indicating that cancer risk in both nations falls within the "acceptable level" range. [ABSTRACT FROM AUTHOR]

Intensifying livestock production by integrating perennial forages has great potential to contribute to sustainable development and livelihoods in the Mekong region. However, the approach taken must be informed by the environmental, social, and cultural context of the region. Accordingly, we review published research papers and reports from relevant research for development projects to identify options for sustainably integrating forages into farming systems, with a focus on sand-dominant soils of southern Laos and Cambodia. First, we examine existing livestock management practices to determine the compatibility of forages as an option to intensify livestock production. Second, we review the environmental properties of rainfed lowland rice systems with sandy soils and their implications for forage growing. Third, we identify and compare the suitability of existing forage genetics that is adapted to these environmental properties. Fourth, we propose adapted varieties, outline appropriate management options, and discuss the sustainable engagement of smallholders in the production of forages. The key findings are as follows: (1) Forages appear compatible with the sociocultural properties of smallholder farming systems in southern Laos and Cambodia because there is an awareness of existing limitations to livestock production, widespread desire to possess livestock for cultural reasons, and mounting pressure to improve the productivity of grazing areas and the efficiency of labor. (2) The limiting properties of the environment are drought, soil acidity, flooding, and soil infertility, which must be addressed in the selection and management of forage genetics. (3) Broadly adapted perennial tropical grasses and herbaceous legumes exist, but these are unlikely to thrive in lowland ecosystems of southern Laos and Cambodia that are prone to both annual flooding and drought. (4) Variations in surface hydrology at the farm scale often result in differentiated environments suitable for differing varieties. Brachiaria sp. hybrid "Mulato II," Panicum maximum, and Stylosanthes guianensis are recommended for drought-prone, acidic sands that are safe from prolonged submergence and would require the least additional management, whilst Paspalum atratum is recommended for low-lying areas with access to irrigation. (5) The transition to perennial forage integration appears to be accessible to farmers and can allow them to rapidly accumulate benefits in terms of saved labor; however, efforts to intensify animal production have been slow and must contend with multiple challenges: poor understanding of animal husbandry and health, cultural views relating to the role of animals in production systems, and poor access to forage and livestock services. These must all be addressed if sustainably intensified animal production is to be achieved in these and similar regions. [ABSTRACT FROM AUTHOR]

The "Golden Triangle" is located on the border between Myanmar, Laos, and Thailand, and slash-and-burn cultivation is an ancient and typical land type in this region. With the development of the "The Belt and Road" strategy of China and the climate change, the vegetation information is bound to change intensively under the combined influence of alternative plantation projects and economic policies. Here we used MOD13Q1-normalized differential vegetation index (NDVI) and meteorological data to analyze the variation of vegetation coverage and its correlation with climatic factors (temperature and precipitation) during the period of 2000–2018 by using trend analysis, stability analysis, and partial correlation analysis. The results showed that the overall vegetation coverage of this region exerted the trend of improvement and became more stable over time. Spatially, the agglomeration degree became weaker as time goes during 2000–2018. The precipitation was more closely correlated with NDVI than temperature, indicating that precipitation could be the main limiting factor influencing vegetation change in this area. The correlation between NDVI and climatic factors exhibited differences among different seasons, with NDVI being less correlated with temperature and precipitation in spring and summer and more correlated with them in autumn and winter. Investigating the long-term vegetation coverage of this region and analyzing the trend of climate change is beneficial to understand the development trend of the ecological environment and resource potential in this region. Simultaneously, it can provide a favorable ecological evaluation for The Belt and Road strategy and provide important scientific suggestions and guidance for the sustainable development of ecosystems and human society under the drastic environmental changes. [ABSTRACT FROM AUTHOR]

Purpose: To assess the effects of intervention with a daily multiple micronutrient powder (MNP) on thiamine, riboflavin, folate, and B12 status among young Laotian children. Methods: Children (n = 1704) aged 6–23 mo, participating in a double-blind placebo-controlled randomized trial were individually randomized to receive daily either MNP (containing 0.5 mg of thiamine, 0.5 mg riboflavin, 150 μg folic acid, and 0.9 μg vitamin B12 along with 11 other micronutrients) or placebo and followed for ~ 36 weeks. In a randomly selected sub-sample of 260 children, erythrocyte thiamine diphosphate (eThDP), plasma folate and B12 concentrations, and erythrocyte glutathione reductase activation coefficient (EGRac; riboflavin biomarker) were assessed at baseline and endline. Results: There was no treatment effect on endline eThDP concentrations (110.6 ± 8.9 nmol/L in MNP vs. 109.4 ± 8.9 nmol/L in placebo group; p = 0.924), EGRac (1.46 ± 0.3 vs. 1.49 ± 0.3; p = 0.184) and B12 concentrations (523.3 ± 24.6 pmol/L vs. 515.9 ± 24.8 pmol/L; p = 0.678). Likewise, the prevalence of thiamine, riboflavin, and B12 deficiencies did not differ significantly between the two groups. However, endline folate concentration was significantly higher in the MNP compared to the placebo group (28.2 ± 0.8 nmol/L vs 19.9 ± 0.8 nmol/L, respectively; p < 0.001), and correspondingly, the prevalence of folate deficiency was significantly lower in the MNP group (1.6% vs 17.4%; p = 0.015). Conclusions: Compared to a placebo, daily MNP for 9 months increased only folate but not thiamine, riboflavin, or B12 status in young Laotian children. Trial registration: The trial was registered at www.clinicaltrials.gov (NCT02428647) on April 29 2015. [ABSTRACT FROM AUTHOR]

Rheological modeling of special concretes such as ultra-high performance concretes (UHPCs), self-compacting concretes (SCCs), or environmentally friendly concretes with low clinker contents but containing many fine particles increases model complexity because high amounts of colloidal and fine particles and complex chemistry result in strongly non-Newtonian rheological behavior. Straight-forward viscoplastic rheological models such as the well-known Bingham- or Herschel-Bulkley approach do not fit the flow behavior on a large scale at and lead to boundary value problems in numerical flow simulations. Increased viscoelastic properties due to chemical admixtures are not described by pure viscoplasticity analysis methods. To fill this gap, our research presents viscoplastic and viscoelastic linear and non-linear rheological characterization methods for common and strongly non-Newtonian cement pastes and combines the methods for a comprehensive viscoelastoplastic modeling of cementitious building materials. We illustrate and discuss the benefits and boundaries of each measurement technique in dependence of cementitious paste complexity. Three solid volume fractions from ϕ = 0.45 to 0.55 and three different flowability ranges, adjusted through varying superplasticizer amounts, were investigated in respect of steady-state and transient yield stress, viscosity, and non-linear viscoelastic material properties. Our results reveal that with increasing solid volume fraction and polymer amount, viscoelastoplastic modeling describes rheological flow on a large flow scale more appropriately than common viscoplastic methods. The results show a new approach for a full quantitative and qualitative rheological classification of cementitious building materials and thus improve the understanding of densely packed colloidal cementitious suspensions. The findings serve as prospective guideline to model complex cementitious building materials both at low and high shear rates, and to find an appropriate rheological description at the boundaries of flow. [ABSTRACT FROM AUTHOR]

The Pleistocene presence of the genus Homo in continental Southeast Asia is primarily evidenced by a sparse stone tool record and rare human remains. Here we report a Middle Pleistocene hominin specimen from Laos, with the discovery of a molar from the Tam Ngu Hao 2 (Cobra Cave) limestone cave in the Annamite Mountains. The age of the fossil-bearing breccia ranges between 164–131 kyr, based on the Bayesian modelling of luminescence dating of the sedimentary matrix from which it was recovered, U-series dating of an overlying flowstone, and U-series–ESR dating of associated faunal teeth. Analyses of the internal structure of the molar in tandem with palaeoproteomic analyses of the enamel indicate that the tooth derives from a young, likely female, Homo individual. The close morphological affinities with the Xiahe specimen from China indicate that they belong to the same taxon and that Tam Ngu Hao 2 most likely represents a Denisovan. Evidence for the presence of Homo during the Middle Pleistocene is limited in continental Southeast Asia. Here, the authors report a hominin molar from Tam Ngu Hao 2 (Cobra Cave), dated to 164–131 kyr. They use morphological and paleoproteomic analysis to show that it likely belonged to a female Denisovan. [ABSTRACT FROM AUTHOR]

Ethnic minorities in northern Laos have experienced changes in their subsistence portfolios since the implementation of nature conservation and rural development projects in the 1990s that may have impacted their nutritional intake and physical activity patterns. We conducted direct weighing dietary surveys and time allocation surveys of 14 couples (n = 28) in the latter half of the rainy season when local people are most vulnerable to undernutrition. Our results revealed a nutritional divergence between two household groups with different subsistence strategies: households more dependent on swidden and secondary forests ate more wild plants and wild boar, and consumed more dietary fiber and vitamin C; while households more dependent on paddy fields ate more aquatic animals and salt, and consumed more niacin and vitamin B12. Physical activity patterns did not differ between the two groups, except for time spent walking. Policy makers should consider the impact of changes in local peoples' subsistence portfolios on nutrition when implementing land use restrictions and resettlement projects. [ABSTRACT FROM AUTHOR]

Soil-transmitted helminth infections represent a large burden with over a quarter of the world's population at risk. Low cure rates are observed with standard of care (albendazole); therefore, a more effective combination therapy (albendazole and ivermectin) is being investigated but showed variable treatment efficacies without evidence of intrinsic parasite resistance. Here, we analyzed the microbiome of Trichuris trichiura and hookworm-infected patients and found an association of different enterotypes with treatment efficacy. 80 T. trichiura-infected patients with hookworm co-infections from Pak-Khan, Laos, received either albendazole (n = 41) or albendazole and ivermectin combination therapy (n = 39). Pre-/post-treatment stool samples were collected to monitor treatment efficacy and microbial communities were profiled using 16S rRNA gene sequencing, qPCR, and shotgun sequencing. We identified three bacterial enterotypes and show that pre-treatment enterotype is associated with efficacy of the combination treatment for both T. trichiura (CRET1 = 5.8%; CRET2 = 16.6%; CRET3 = 68.8%) and hookworm (CRET1 = 31.3%; CRET2 = 16.6%; CRET3 = 78.6%). This study shows that pre-treatment enterotype enables predicting treatment outcome of combination therapy for T. trichiura and hookworm infections. Trial registration: ClinicalTrials.gov, NCT03527732. Registered 17 May 2018, https://clinicaltrials.gov/ct2/show/NCT03527732. Little is known about the cause of treatment failure of soil-transmitted helminth infections. Here, the authors show that pre-treatment gut microbial community composition enables predicting treatment outcome for Trichuris trichiura and hookworm infections. [ABSTRACT FROM AUTHOR]

Managing transboundary river basins requires balancing tradeoffs of sustainable water use and coping with climate uncertainty. We demonstrate an integrated approach to exploring these issues through the lens of a social-ecological system, combining remote and in-situ earth observations, hydrologic and climate models, and social surveys. Specifically, we examine how climate change and dam development could impact the Se Kong, Se San and Sre Pok rivers in the Mekong region. We find that climate change will lead to increased precipitation, necessitating a shift in dam operations, from maintaining low flows to reducing flood hazards. We also find that existing water governance systems in Laos, Vietnam, and Cambodia are ill-prepared to address the problem. We conclude that the solution space for addressing these complex issues will be highly constrained unless major deficiencies in transboundary water governance, strategic planning, financial capacity, information sharing, and law enforcement are remedied in the next decades. [ABSTRACT FROM AUTHOR]

The effect of shearing conditions in the coating process on the uniformity of the coated layer of dense silica slurry is investigated. The pH 6.8 test slurry mainly used in this study forms a nonuniform coated layer only on the condition of large shear strain and low shear rate. The same shearing dependency was observed using not only a laboratory-scale doctor blade but also a pilot-scale comma coater. The test slurry exhibits two-step yielding, and the internal structure of the slurry is gradually destroyed after the second yielding. When the shear strain applied is within the second yielding, the test slurry is in equilibrium and a uniform coated layer is formed. As strain is increased further, the slurry changes from the viscoelastic fluid to Newtonian. When the shear strain is beyond the second yielding but the structural destruction is not completed, a nonuniform coated layer is formed. A higher coating speed or sufficiently large shear deformation, which effectively destroys the internal structure, is favorable to obtain a uniform coated layer. [ABSTRACT FROM AUTHOR]

The illegal wildlife trade has increasingly been linked to organized crime in recent years. In particular, Chinese crime groups seem to be major players in more organized forms of this trade. This article examines the involvement of Chinese organized crime groups in the trade of wildlife in the borderlands of the Golden Triangle. We will discuss the representation of Chinese crime groups in the illegal wildlife trade by looking at: a) the diversification of these crime groups into wildlife crimes and b) the outsourcing of activities to local opportunistic crime groups in neighboring Laos and Myanmar. We conclude that the different representations of Chinese crime groups overseas involved in the illegal wildlife trade are important in order to understand the roles of diversification and outsourcing. [ABSTRACT FROM AUTHOR]

The morphological developments in laboratory-reared larval and juvenile Cirrhinus molitorella and larval C. microlepis were described, and ontogenies (including yolk sizes and absorptions, fin-ray and myomere numbers, allometric changes in the snout, upper jaw, head and pre-anal lengths, maximum body depth, eye diameter and melanophore distributions) were compared. Body lengths (BL) just after hatching were smaller in C. molitorella [3.3 ± 0.1 (mean ± SD) mm] than in C. microlepis (4.4 ± 0.1 mm), and subsequent increase in body lengths were slower in C. molitorella than in C. microlepis. Yolk sizes just after hatching were correspondingly smaller in C. molitorella than in C. microlepis and the yolks were completely absorbed by ca. 95 hours after hatching in the former and ca. 118 hours in the latter. In C. molitorella, fin-rays started appearing at a smaller size than in C. microlepis, with full complements attained by 14.4 mm BL (day 35) in the former, while they did not attain by 16.4 mm BL (day 20) in the latter. Allometric changes started in smaller sizes in C. molitorella than in C. microlepis. Total myomeres were 38–41 in C. molitorella and 39–43 in C. microlepis. Melanophore distributions progressed similarly in both species, except for a darker deposition on the caudal peduncle of C. molitorella of ca. 7–10 mm BL. Larvae of these species were identifiable mainly by differences in fin-ray numbers and allometries by size. [ABSTRACT FROM AUTHOR]

The capability of Pleistocene hominins to successfully adapt to different types of tropical forested environments has long been debated. In order to investigate environmental changes in Southeast Asia during a critical period for the turnover of hominin species, we analysed palaeoenvironmental proxies from five late Middle to Late Pleistocene faunas. Human teeth discoveries have been reported at Duoi U'Oi, Vietnam (70–60 ka) and Nam Lot, Laos (86–72 ka). However, the use of palaeoproteomics allowed us to discard the latter, and, to date, no human remains older than ~ 70 ka are documented in the area. Our findings indicate that tropical rainforests were highly sensitive to climatic changes over that period, with significant fluctuations of the canopy forests. Locally, large-bodied faunas were resilient to these fluctuations until the cooling period of the Marine Isotope Stage 4 (MIS 4; 74–59 ka) that transformed the overall biotope. Then, under strong selective pressures, populations with new phenotypic characteristics emerged while some other species disappeared. We argue that this climate-driven shift offered new foraging opportunities for hominins in a novel rainforest environment and was most likely a key factor in the settlement and dispersal of our species during MIS 4 in SE Asia. [ABSTRACT FROM AUTHOR]

A survey of small-holder banana farms was undertaken in February/March 2019 in Savannakhet, Salavan, Sekong and Champasak provinces in southern Lao People's Democratic Republic (Lao PDR) to establish which banana leaf pathogens were present. Twenty-five farms were visited, seven different cultivars were assessed, and 13 leaf samples with characteristic symptoms of banana freckle disease collected. Phyllosticta musarum was detected on the variety 'Kuay Nam' in each of the four provinces surveyed. Phyllosticta cavendishii was detected in Salavan, Sekong and Champasak. Phyllosticta musaechinesis was recorded from Champasak. This is the first time these three species have been recorded associated with banana freckle disease in the Lao PDR. [ABSTRACT FROM AUTHOR]

Herbaceous plant diversity including rare aquatic species has been lost in many countries by agricultural intensification and abandonment. In paddy fields of the Lao People's Democratic Republic (Lao PDR), irrigation facilities have been constructed rapidly since 1997. The aim of this study was to clarify the impacts of double rice cropping accompanied by the introduction of irrigation systems on herbaceous plant diversity and utilization in paddy fields of southern Lao PDR. Ground vegetation surveys and interviews were conducted in Kok Deau and Lak 30 villages in Champasak Province, and propagule bank survey was conducted in Kok Deau village. The species richness and species diversity, measured by the Shannon's diversity index, were not significantly different between the irrigated and rainfed paddies (p > 0.05), when compared in both the wet and dry seasons. However, double rice cropping with irrigation systems affected herbaceous plant species composition in paddy fields. Increased use of chemical fertilizers in irrigated paddies resulted in predominance of tall undesirable species, such as Fimbristylis miliacea (L.) Vahl and Echinochloa colona (L.) Link. Small and frequently submerged species were dominant in the ground vegetation and propagule banks of the rainfed paddies. Since small submerged species are often sensitive to environmental changes, increase of irrigated paddy area may lead to a decrease in the variety of aquatic herbaceous plants in Lao PDR. While a total of 9 herbaceous plant species were utilized as foods in the villages, no change was recognized by farmers in species composition and frequency of utilization of paddy plants as food before and after the development of the irrigation systems. [ABSTRACT FROM AUTHOR]

Cattle and buffaloes, popular protein sources worldwide, are intermediate hosts for several Sarcocystis species. These coccidian protozoans cause sarcocystosis resulting in subclinical and chronic infections in striated muscles by forming macrocysts or microcysts. In Thailand, Lao People's Democratic Republic, and Cambodia, Sarcocystis species have been reported, but molecular identification has been lacking. This study investigates the prevalence of infection, histo-morphology, and molecular identification of Sarcocystis species in hearts of cattle and buffalo sold in local markets. A phylogenetic tree inferred from a portion of the 18S ribosomal (r) RNA gene was used to identify the genus and species of Sarcocystis. The mitochondrial cytochrome c oxidase subunit 1 (cox-1 gene) was sequenced to confirm the species of host tissue. In Thailand, Sarcocystis was detected in 66.7% (14/21) of samples. In Lao People's Democratic Republic, 90% (9/10) of samples were infected and in Cambodia 100% (8/8). For the first time from these countries, we report Sarcocystis cruzi, Sarcocystis heydorni, and Sarcocystis levinei found in taurine cattle (Bos taurus) and water buffalo (Bubalus bubalis). Zoonotic protozoan transmission needs to be controlled by inspection activities by local health inspectors, and appropriate action is required at all points in the food chain by competent authorities to protect consumer health and prevent sarcocystosis in cattle and water buffaloes. [ABSTRACT FROM AUTHOR]

Strategic dam planning and the deployment of decentralized renewable technologies are two elements of the same problem, yet normally addressed in isolation. Here, we show that an integrated view of the power system capacity expansion problem could have transformative effects for Southeast Asia's hydropower plans. We demonstrate that Thailand, Laos, and Cambodia have tangible opportunities for meeting projected electricity demand and CO2 emission targets with less hydropower than currently planned—options range from halting the construction of all dams in the Lower Mekong to building 82% of the planned ones. The key enabling strategies for these options to succeed are solar PV and regional coordination, expressed in the form of centralized planning and cross-border power trading. The alternative expansion plans would slightly increase the cumulative costs (up to 2.4%), but substantially limit the fragmentation of additional river reaches, thereby offering more sustainable pathways for the Mekong's ecosystems and riparian people. Hydropower dams in the Lower Mekong basin have profound impact on the riverine ecosystems. Here the authors use strategic dam planning and power system modelling to show that there are economically and technically feasible alternatives to these dams with solar energy and power trading. [ABSTRACT FROM AUTHOR]

A new whitefly species, Pealius gallae sp. nov. forming pit galls on Celtis philippensis Blanco discovered in the Andaman Islands, is described and illustrated. Leaf pit galls were formed in the microhabitat of the puparia, each pit was observed with a single puparium, the opposite side of the galls was convex, easily recognizable by chlorotic spots; older galls turn brown and brittle. This is the first authentic record with illustrations of any leaf pit gall forming whitefly. The specialised gall inducing insects may pose extinction risks with limited host range. The new whitefly differs from Pealius cinnamomi David and Sundararaj in the habitus, gall forming nature, number of submarginal setae, vasiform orifice shape, broad tracheal folds and pattern of tubercles in it. [ABSTRACT FROM AUTHOR]

Determining the density trends of a guild of species can help illuminate their interactions, and the impacts that humans might have on them. We estimated the density trends from 2013 to 2017 of the clouded leopard Neofelis nebulosa, leopard cat Prionailurus bengalensis and marbled cat Pardofelis marmorata in Nam Et—Phou Louey National Park (NEPL), Laos, using camera trap data and spatial capture-recapture models. Mean (± SD) density estimates (individuals/100 km2) for all years were 1.77 ± 0.30 for clouded leopard, 1.50 ± 0.30 for leopard cat, and 3.80 ± 0.70 for marbled cat. There was a declining trend in density across the study years for all three species, with a ≥ 90% probability of decline for clouded leopard and leopard cat and an 83% probability of decline for marbled cat. There was no evidence that mesopredator release occurred as a result of tiger (Panthera tigris) and leopard (P. pardus) extirpations. We believe that snaring, the factor that led to the extirpation of tiger and leopard in NEPL, is now contributing to the decline of smaller felids, to an extent that over-rides any potential effects of mesopredator release on their densities and interactions. We recommend that the NEPL managers implement a more systematic and intensified snare removal program, in concert with extensive community outreach and engagement of local people to prevent the setting of snares. These actions might be the only hope for saving the remaining members of the felid community in NEPL. [ABSTRACT FROM AUTHOR]