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Mung bean (Vigna radiata) is an annual legume that adapts well to dry zones. In Burkina Faso, it is considered an orphan crop. The aim of this study was to gain a better understanding of the crop by evaluating the seed and fodder yields of ten accessions. The accessions were evaluated on thirteen quantitative variables in a Fisher block design with three replications. High genetic variability between accessions was observed. Positive and negative correlations were also observed between variables. Principal component analysis (PCA) explained 65.64% of the total variability between the accessions studied. Accession M06 proved to be the most productive in terms of seed yield (i.e., 3.54 t/ha), whereas M40 reached the highest forage yield (i.e., 3.15 t/ha). Accession M42 was the most judicious, with 95% early maturity (62 days), the highest number of pods (114), good seed yield (3.06 t/ha) and forage yield (2.5 t/ha). These evaluated accessions may be taken into account in future mung bean breeding programs.

Mung bean (Vigna radiata) is an annual legume that adapts well to dry zones. In Burkina Faso, it is considered an orphan crop. The aim of this study was to gain a better understanding of the crop by evaluating the seed and fodder yields of ten accessions. The accessions were evaluated on thirteen quantitative variables in a Fisher block design with three replications. High genetic variability between accessions was observed. Positive and negative correlations were also observed between variables. Principal component analysis (PCA) explained 65.64% of the total variability between the accessions studied. Accession M06 proved to be the most productive in terms of seed yield (i.e., 3.54 t/ha), whereas M40 reached the highest forage yield (i.e., 3.15 t/ha). Accession M42 was the most judicious, with 95% early maturity (62 days), the highest number of pods (114), good seed yield (3.06 t/ha) and forage yield (2.5 t/ha). These evaluated accessions may be taken into account in future mung bean breeding programs. [ABSTRACT FROM AUTHOR]

Agriculture is the largest water user of all sectors. In arid regions in particular, achieving efficient water use in agriculture is an important way to solve water scarcity. However, the difference in water use efficiency between arid and humid regions has long been a focus of academic debate. Many studies consider water use efficiency to be higher in humid areas due to the abundance of water resources. This view is based on the fact that less irrigation in humid areas may lead to higher crop yields and better conditions for agricultural production; however, it ignores the efforts of researchers and agricultural workers in arid zones who have attempted to develop efficient water-saving technologies, as well as the effect of natural conditions on agricultural production. Correctly evaluating the efficiency of agricultural water use in arid zones is important for achieving efficient use of water resources, as well as for water management decisions. This study calculates the yield structure and water productivity of typical crops in both arid and humid regions in China based on the footprint theory and other methodologies. This approach allows for an accurate assessment of irrigation water benefits in various regions, providing a scientific basis for improving agricultural water use efficiency under different climatic conditions. The study results indicate that the average reliance on blue water for wheat and cotton gradually increases from 49.9% to 93.6% as regional aridity intensifies, ranging from the Central China Humid Region to the Northwest China Arid Region. Similarly, the average contribution of blue water to crop yield rises from 31.0% to 100%, while irrigation water productivity increases from 0.27 kg·m−3 to 0.53 kg·m−3. Finally, this study concludes that, in arid zones with lower precipitation and more hours of sunshine, a higher dependence on blue water for crop growth and development leads to a higher productivity of irrigation water. In addition, in arid zones, the focus should be on optimizing the use of irrigation water and improving irrigation technology and efficiency, while, in humid zones, there should be more use of natural precipitation to efficiently reduce dependence on irrigation water. [ABSTRACT FROM AUTHOR]

Deforestation is a key factor in global climate change, severely impacting ecosystem services. Effective implementation of reducing emissions from deforestation and forest degradation (REDD+) initiatives is essential for mitigating this change. Reforestation is a sustainable way to mitigate deforestation effects. We studied the impact of assisted natural regeneration (ANR) on restoring dry forest land, increasing biodiversity, structure, and carbon stock. Reforestation units were established at a multiple row planting system in a dry tropic region. We selected 63 plots, each 20 m × 20 m, categorized into multiple row–mixed plantation (MRMP) and multiple row–unmixed plantation (MRUP). We measured tree height and diameter at breast height (DBH) and evaluated biodiversity indices, including the Shannon–Weiner Index (SWI), species richness, evenness, and Important Value Index (IVI). Carbon stock was estimated using allometric equations. We identified 931 individual trees representing 27 species, 24 genera, and 14 families. MRMP showed significantly higher biodiversity, species richness, and evenness than MRUP. Terminalia arjuna was the most dominant species (IVI=124.45), followed by Khaya senegalensis (53.84). Survival rates exceeded 90 % for T. arjuna, K. senegalensis, Madhuca longifolia, and Pongamia pinnata (p

Groundwater resources are depleting due to phenomena such as significant climate change and overexploitation. Therefore, it is essential to estimate water production and identify potential groundwater zones. An integrated conceptual framework comprising GIS and the analytical hierarchy process (AHP) has been applied for the present study to identify groundwater potential areas in the Thalawa division of Sri Lanka. The criteria, including rainfall, soil types, slope, stream density, lineament density, geology, geomorphology, and land use, were taken into account as the most contributing factors when identifying the groundwater zones. Weights were allocated proportionally to the eight thematic layers according to their importance. Hierarchical ranking and final normalized weighting of these determinants were performed using the pairwise comparison matrix (PCM) available in AHP. Based on the results obtained, the groundwater potential zone (GWPZ) was classified into three regions: low potentiality (33.4%), moderate potentiality (55.8%), and high potentiality (10.6%). Finally, the zoning map was compared to find consistency with field data on groundwater discharge and depth taken from 18 wells in the division. The results revealed that the GIS-multi-criteria decision-making (MCDM) approach brings about noticeably better results, which can support groundwater resource planning and sustainable use in the research area. [ABSTRACT FROM AUTHOR]

In the field of power transmission, underground cables are subjected to various factors that influence their load capacity. One such significant factor, often overlooked, is the extreme environmental conditions prevalent in certain geographical regions. This study particularly focuses on regions where summer temperatures exceed 50℃ and the soil, due to excessive dryness, exhibits high thermal resistivity. The current study explores the impact of these harsh environmental conditions on the current-carrying capacity (ampacity) of underground power cables. A derating factor for dry zone formation around these cables has been proposed, calculated for various types of native soil. The standard IEC-60287 has been adhered to as a reference for these calculations. The software ANSYS has been employed to compute the temperature distribution around the cables in different types of soil, using relevant experimental data. The results indicate that the formation of dry regions in the soil begins at differing temperatures and rates depending on the soil's composition. This study thus underscores the critical role of environmental factors and soil conditions in determining the ampacity of underground power cables. It also highlights the necessity of incorporating these factors into design considerations for optimal cable performance. [ABSTRACT FROM AUTHOR]

Sri Lanka is a tropical island located in the Indian Ocean that consists of two distinct climatic zones: the dry zone and the wet zone. Rain water scarcity of the dry zone for agricultural use has resulted in the development of man-made tank systems referred to as tank cascade systems (TCS). Over the years, these systems have integrated with the natural environment of the dry zone. Recently, agrochemicals and other pollutants have come in contact with these traditional water-preserving TCSs, leading to health and environmental concerns. These systems are studied in qualitative ways in the literature. However, there is a lack of mathematical models to capture, predict, and better understand the dynamics of TCS pollution. Therefore, in this work, for the first time, a time-dependent mathematical model for a TCS is developed and applied to study pollutant dynamics. The mathematical model is developed by identifying key ecological components in a generic TCS and applying time dependent water and pollutant balance equations over these components. The equations are then numerically solved and simulations are conducted using the Xcos simulation environment of the open-source software Scilab. The water volume and pollutant concentration variations in the Kadirgama TCS are studied. The simulation results are then compared against available measured data from the literature. The simulation results indicate that the water storage in different TCS components, ranging from 30,000 to 60,000 m3 in the Nawakkulama system and 100,000 to 300,000 m3 in the Kadiragama system facilitate the ecological functioning of the component as well as the functioning of the entire TCS. Pollutant concentration peaks ranging from 0.4 to 7 kg m−3 are observed during times of low water availability in some components of the system. The results also indicated a system dynamic time scale in the order of several months, which demonstrated that the TCS are long residence time systems built to preserve water to cope with the water scarcity in the dry zone. The developed model in the present work provides a tool to study the pollutant dynamics in various ecological components of a TCS under measured or user given input data. It can therefore be used to identify the effects of modern agricultural and environmental decisions on the functioning of these components, therefore providing a tool to aid in the decision-making processes related to the TCS systems. [ABSTRACT FROM AUTHOR]

This study demonstrated the use of statistical process control (SPC)-I chart as a tool to estimate extreme rainfall. This study was conducted in the tropical dry zone of Sri Lanka. Rainfall data (1971–2017) from 19 meteorological stations were used to make SPC-I charts. The probability of having extreme rainfall in a particular month was modelled with the binary time series mixed model using the GLIMMIX procedure. Results showed a significantly different probability of occurrence of extreme rainfall in base and test periods in the dry zone. A higher number of extreme rainfall was recorded at all the rainfall stations during the test period. Monthly changes in occurrence of extreme rainfall were also observed. Comparing the results of the study with the existing results, it is found that SPC-I charts can be used as a tool to explore extreme rainfall. Compared to climate-related extreme assessment methods, SPC-I chart is simple and can accommodate even monthly rainfall data. The result of the study is useful in agricultural planning in the dry zone, Sri Lanka. Research highlights: The use of SPC-I chart in detecting extreme rainfall is exhibited with the support of binary time series mixed model using the GLIMMIX procedure and chi-square test. A higher probability of occurrence of extreme rainfall is observed in test periods than the base period for both cropping seasons, Yala and Maha in tropical Sri Lanka. Monthly changes of occurrence of extreme rainfall were observed in the dry zone of Sri Lanka, probably due to climate change. Comparing the findings of the present method with the existing studies, the SPC-I charts can be used to explore extreme rainfall analysis. [ABSTRACT FROM AUTHOR]

This study was focused on explaining food selectivity in endemic Sri Lanka Grey Hornbill Ocyceros gingalensis to fill the gaps in the behavioral ecology of this endemic species. The study was conducted within Mihintale Sanctuary for five months from December 2015 to April 2016. Ringed hornbills were used to monitor the number of food items that were consumed from within the Food Abundance Index (FAI) and quantify the distribution and availability of resources to examine the potential of fruit selectivity. Thirteen fruiting plant families were recorded as preferred food. Food consumption and FAI values are not significantly correlated (r = 0.60, p = 0.285). The dietary composition increased in the breeding season due to a higher requirement for nutrients by the nestlings. Nutrient analysis results revealed that moisture (H = 7.50, p = 0.006), fiber (H = 6.53, p = 0.011), and ash (H = 6.07, p = 0.013) components were significant between eaten and non-eaten fruits. The amount of all the nutrients available in the fruits as well as FAI does not directly affect the fruit selectivity of the Sri Lanka Grey Hornbill in the Mihintale Sanctuary. This fruit selection and the seed dispersal ability of the Sri Lanka Grey Hornbill contributes to maintaining the ecosystem diversity and forest regeneration, especially in the Dry Zone in Sri Lanka. [ABSTRACT FROM AUTHOR]

This paper demonstrates how greater engagement with liminality – as a concept and lived experience – can expand scholarly conceptualisations of health/disease in contaminated spaces. Drawing on ethnographic fieldwork conducted in Sri Lanka's dry zone between 2013 and 2017, I focus on residents' encounters with chronic kidney disease diagnosis in a region where the causes of illness are uncertain, the consequences of disease are often deadly, and the possibilities of developing sickness in the future are both unpredictable and ever‐present. Specifically, I examine how residents of kidney disease hotspots negotiate various attempts to categorise them as being, or not being, healthy in ways that give rise to experiences of liminality. Building on work in feminist disability studies, I conceptualise "undiagnosis" and "anticipatory diagnosis" as two such liminal states of health that reconfigure medical and social practices in the dry zone. As part of this analysis, I explain why residents are so reluctant to get screened for kidney disease and demonstrate how they strategically mobilise moments of "undiagnosis" to resist patient subjectivities and prolong existing lifeways. I then turn to a discussion of anticipatory diagnosis, which describes the practice of re‐classifying residents of disease hotspots who are not yet sick as embodying the potential to become ill at any time. Frequently deployed by the state, medical practitioners, and non‐dry zone communities, I demonstrate how this practice collapses categories of "at‐risk" and "diseased" in external categorisations of residents' future health status. In short, liminality comes to be embodied through the constant anticipation of disease despite uncertainty about who will actually become sick and why. Tying these experiences together, I elucidate how geography matters to the constitution of liminal states of health and crucially demonstrate how this liminality helps reproduce place attachments as well as forms of geographic differentiation in the shadow of toxic contamination. [ABSTRACT FROM AUTHOR]

Environmental exposure to trace elements has been widely suspected as an etiological factor for the emergence of chronic kidney disease of undetermined origin (CKDu) that prevails in certain districts of the dry zone areas of Sri Lanka. Contaminated rice can be act as a host for potentially toxic trace elements that ultimately led to health hazards; thus, rice soils were investigated in detail, giving particular attentions to identified CKDu hotspots. A total of 102 rice soil samples were collected from main climatic zones viz. wet and dry zones including CKDu hotspots. In addition to pH, electrical conductivity and cation exchange capacity, acid extracted major and trace element contents in rice soils were determined by using ICP-MS. Significant differences were observed for Mn, Ni, Cu, Zn, and Pb contents between climatic zones. Arsenic and Pb contents in soils were lower than the levels reported in soils from other regions of the world, though significantly higher contents were observed in CKDu regions compared to non-endemic wet zone regions. Calculation of enrichment factor revealed that soils in both dry and wet zones were moderately enriched with As, Cd, and Pb, suggesting an influence of anthropogenic processes. Twenty percent of the wet zone samples showed significant enrichment of Ni, Cu, and Zn. Geo-accumulation index assorted that the studied soil samples were uncontaminated to moderately contaminated, implying that rice soils in both climatic zones are not alarmingly contaminated with toxic trace elements. However, regular and continuous monitoring of rice soil quality is extremely important. [ABSTRACT FROM AUTHOR]

The tank cascade system, which emerged as early as the fifth century BC in Sri Lanka's dry zone, has been portrayed as one of the oldest water management practices in the world. However, its important function as flood management has not yet been thoroughly examined. In this paper, we argue that the main principle behind the tank cascade system is not only to recycle and reuse water resources by taking advantage of natural landscapes but also to control floods. This paper examines the evolution of traditional water management and flood mitigation techniques that flourished in pre-colonial Sri Lanka. This historical examination also sheds light on recent policies that exhibited renewed interests in revitalizing some aspects of the tank cascade system in Sri Lanka's dry zone. This paper shows how ancient Sinhalese engineers and leaders incorporated traditional scientific and engineering knowledge into flood mitigation by engendering a series of innovations for land use planning, embankment designs, and water storage technologies. It also discusses how this system was governed by both kingdoms and local communities. Water management and flood control were among the highest priorities in urban planning and management. The paper thus discusses how, for centuries, local communities successfully sustained the tank cascade system through localized governance, which recent revitalized traditional water management projects often lack. [ABSTRACT FROM AUTHOR]

Fluoride is a beneficial trace element for human health as its deficiency and excess levels can cause detrimental health effects. In Sri Lanka, dry zone regions can have excessive levels of fluoride in drinking water and can cause dental and skeletal fluorosis. In addition to drinking water, traditional habits of tea consumption can cause an additional intake of fluoride in the population. A total number of 39 locally blended black tea samples were collected from a village where chronic kidney disease with undetermined origin (CKDu) is prevalent. In addition, unblended tea samples were obtained from tea-producing factories. The fluoride contents in infusions of 2% weight per volume (w/v) were measured using calibrated ion-selective fluoride electrodes. The mean fluoride content was 2.68±1.03 mg/L in loose tea, 1.87±0.57mg/L in packed tea samples, and 1.14±0.55 mg/L in unblended tea. Repeated brewing of the same tea leaves showed that over 50% of fluoride leached into the solution in the first infusion. An estimate of the daily total average fluoride intake via tea consumption per person is 2.68 mg per day. With groundwater in many dry zone regions in Sri Lanka showing high fluoride levels that exceed 0.5 mg/L, the additional daily intake can rapidly exceed recommended thresholds of 2 mg/day. This can add to adverse health impacts that might also relate to CKDu. [ABSTRACT FROM AUTHOR]

War influences wildlife in a variety of ways but may influence their escape responses to approaching threats, including humans, because of its effect on human populations and behavior and landscape change. We collected 1,400 flight initiation distances (FIDs) from 157 bird species in the dry zone of Sri Lanka, where civil war raged for 26 years, ending in 2009. Accounting for factors known to influence FIDs (phylogeny, starting distance of approaches, body mass, prevailing human density, group size, and location), we found that birds have longer FIDs in the part of the dry zone that experienced civil war. Larger birds—often preferred by human hunters—showed greater increases in FID in the war zone, consistent with the idea that war was associated with greater hunting pressure and that larger birds experienced longer-lasting trauma or had more plastic escape behavior than smaller species. While the mechanisms linking the war and avian escape responses remain ambiguous, wars evidently leave legacies that extend to behavioral responses in birds. [ABSTRACT FROM AUTHOR]

This study was intended to assess the impact of coconut based Anacardium occidentale (Cashew) agroforestry systems on soil fertility of degraded coconut lands in wet, intermediate and dry zones of Sri Lanka. Two treatments were evaluated according to randomized complete block design with three replicates. Coconut based agroforestry systems intercropped with A. occidentale and sole coconut were evaluated as two treatments. Soils from three depths were analyzed for its’ chemical, physical and biological properties. According to the esults, higher total N, available P and exchangeable K levels were shown in sole coconut systems than A. occidentale intercropped system while the higher total N levels (2% higher than top soil and 27% higher than deepr soil) were observed in sub soils compared top and deep soils. Higher P content was observed in top soils than in deeper soils. The exchangeable K was observed in higher quantities in sub soil than in deeper soils and was varied with locations. Organic matter content in intercropping of A. occidentale has been increased by 37% and the highest was observed in top soils. Soil bulk density has been reduced by 9% in A. occidentale intercropped system enhancing the root growth. Bulk density has been increased with the depth of the soil. Higher soil microbial activity was observed in A. occidentale intercropped system and it was 22% higher than sole coconut system. Sole coconut system has 50% higher soil moisture percentage and the highest was recorded in sub soils. This study confirms that intercropping of A. occidentale has a positive effect on improving soil fertility of degraded coconut growing soils in wet, intermediate and dry zones of Sri Lanka.

Sri Lanka harbours 20 scorpion species belonging to four families, of which 15 are endemic. The distribution and ecology of scorpion fauna in Sri Lanka is poorly known. In this study, we surveyed the diversity of scorpions in the Polonnaruwa Archaeological Reserve in the dry zone of Sri Lanka. Microhabitats were thoroughly observed using the direct visual encounter method and UV lights from July to November 2018 for about seven hours (19.00-02.00 h) by two to three observers. Species, abundance, age/sex, and microhabitat features were recorded. Diversity indices, including α-diversity and β-diversity, were calculated. Heterometrus swammerdami was the most abundant species recorded, while Isometrus thwaitesi was the rarest. Reddyanus loebli and R. besucheti were common in both open and forest habitat types. Charmus laneus was recorded for the first time in Polonnaruwa. The highest Shannon Index and Margalef Diversity Index values were recorded in open habitats, but species evenness was low compared to forest habitats. Sørensen index values showed a 58% species similarity between two habitats. The results presented here contribute to the knowledge of the diversity of scorpions in these historically significant sites. This can serve as a basis for future research on the impact of habitat modification and fragmentation on populations, distribution and ecology of scorpions. [ABSTRACT FROM AUTHOR]

Farming systems promoting crop production are important to match food security concerns. This research explores food security levels of different farming systems using the indicators of food availability, food access and food utilization. In Yamethin District, various households cultivated a combination of different crop of farming systems. Structured interviews were conducted with 282 farm households: monoculture farming system, multiple farming systems, and mixed farming system. The data were analyzed using weighted sum models. The assessment identified that the monoculture farming system had low food availability, high food access and moderate food utilization, while the multiple and mixed farming systems had moderate food availability, high food access and low food utilization. The study suggested that monoculture farm households should grow vegetables and build up crop exchanges to fulfill staple rice and increase food availability. Moreover, multiple and mixed farm households should allocate farm plots based on average farm land to hold high food security. Under adequate irrigation, 70% farm land for staple rice, 20% farm land for field crops and the rest (10%) for vegetables should be carried out from season to season. In rain-fed area, similar farm allocation should be performed during monsoon and short-season crops during post monsoon season. [ABSTRACT FROM AUTHOR]

Chronic kidney disease of unknown etiology (CKDu) is the main health issue in the dry zone of Sri Lanka. Despite many studies carried out, causative factors have not been identified yet clearly. According to the multidisciplinary researches carried out so far, potable water is considered as the main causative factor for CKDu. Hence, the present study was carried out with combined isotopic and chemical methods to understand possible relationships between groundwater; the main drinking water source, and CKDu in four endemic areas in the dry zone. Different water sources were evaluated isotopically (2H, 3H and 18O) and chemically from 2013 to 2015. Results revealed that prevalence of CKDu is significantly low with the groundwater replenished by surface water inputs. It is significantly high with the groundwater stagnated as well as groundwater recharged from regional flow paths. Thus, the origin, recharge mechanism and flow pattern of groundwater, as well as geological conditions which would be responsible for natural contamination of groundwater appear as the main causative factors for CKDu. Therefore, detailed investigations should be made in order to identify the element(s) in groundwater contributing to CKDu. The study recommends providing drinking water to the affected zones using water sources associated with surface waters. [ABSTRACT FROM AUTHOR]

The tank cascade system (TCS) has been used for over 2000 years for water management in Sri Lanka. Since surface water is limited in the dry zone of Sri Lanka, agricultural production, especially of upland crops, relies on groundwater for irrigation. We sampled 29 wells in the Ulagalla cascade, a prominent TCS near Anuradhapura city in the dry zone of Sri Lanka, in Yala (dry) and Maha (wet) seasons, the two main cropping seasons in Sri Lanka. We evaluated the suitability of groundwater for irrigation using the analytic hierarchy process and geographical information system. Water quality did not vary notably between seasons. However, it deteriorated with the onset of high intensity heavy rain, especially during the Maha season. A water quality zoning map indicated that groundwater in 4% and 96% of the study area is suitable and moderately suitable for irrigation, respectively. Irrigation water quality in tank cascade landscapes and similar environments can be assessed using this methodology and our results.

The Central Dry Zone area of Myanmar is the most water stressed and one of the most food insecure regions in the country. Agriculture is the most important economic sector in Myanmar as it is essential for national food security and a major source of livelihood. The adverse effects of climate change are believed to be a major constraint to food insecurity and flood risk. This paper gives a structured overview of the current scientific knowledge available and reveals the relevance of this information with regard to food security and flood risk dynamics in central dry zone area of Myanmar. [ABSTRACT FROM AUTHOR]

The known distribution in Sri Lanka of the endemic freshwater crab Oziothelphusa mineriyaensis Bott, 1970 was limited to 2 known localities in the dry zone. In this study of the distribution of this species in the North Central Province of Sri Lanka, we identified 5 new localities. Our findings expand the extent of occurrence from 168 km² to 1467 km². Our new records are 62 km from the type locality and up to 89 km from the previous records in Anuradhapura District and 20 km from previous record in Polonnaruwa District. These data provide important new information needed for the conservation of this endangered species in Sri Lanka. [ABSTRACT FROM AUTHOR]

A 1D baking model was previously developed to improve the understanding of transport phenomena and bubble formation inside dough. Using this model, the present study focused on crust setting and its particular behavior. Simulation was used to study the influence of various parameters that govern crust setting and its characteristics such as thickness and porosity. On the basis of a literature review, the crust was defined as the “dry zone,” a region where the water content represents less than 0.60 kg/kg of dry matter. The mechanisms responsible for total water loss and crust setting were proposed in paper I and validated for multiple operating conditions: water loss is essentially driven by heat transport and to a lesser extent by the mechanism of water transport by evaporation–condensation–diffusion. In the present study, a sensitivity analysis of parameters of different driving mechanisms was undertaken through which it was possible to establish a hierarchy of the key parameters from a technological point of view. Overall heat transfer coefficient at the top of the loaf and thermal conductivity, or more generally the ratio between top and bottom heat fluxes, were ranked as the main parameters affecting crust setting and the water loss, thus suggesting a possible control of the process through the parameters evaluated. [ABSTRACT FROM PUBLISHER]