bluuebunny/crossref_metadata_2025_split huggingface dataset:
Biofilm-based Biofertilizers and Microbial Mixed Cultures: Are they Different on Plant Growth?
Authors: Senanayake D.M.N.  , Seneviratne G.  , Jayasinghe J.A.W.W.  
Published: February 2024

Intensive agriculture has increased crop yields, but at the same time has posed severe environmental problems. Organic agriculture is a good alternative to intensive agriculture in safeguarding the environment. However, handling bulky organic materials in large-scale cultivations limits the widespread use of organic agriculture. In this context, microbial biofertilizers can play a major role in replacing intensive agriculture, which is based only on chemical inputs. As a recent development in microbiology, biofilms have been formulated in vitro to be used as biofertilizers, which are then called biofilmed biofertilizers (BFBFs). Biofilms are complex, surface-attached communities of multiple microbial species that produce a wider range of ecologically important biochemicals. The present study investigated the biochemical expression and the effect on plant growth of BFBFs and just mixed cultures of the BFBF microbes, using tomato (Solanumlyco persicum) as the test plant. A plant assay and a pot experiment were carried out to evaluate this. Fourier Transform Infrared (FTIR) spectroscopy was used to analyze the biochemical expression of the BFBFs and the mixed cultures. Seeds inoculated with BFBF showed significantly higher germination percentages and seedling lengths than the mixed cultures. The BFBFs and the mixed culture increased the vigor index of tomatoes up to 177% and 120%, respectively over the non-amended control. BFBFs inoculations significantly improved the root growth and resulted in significantly higher biomass production and plant height than the mixed cultures, and this was proportional to the production of more diverse functional groups and nitrogenous compounds by the BFBFs. Thus, it can be concluded that the BFBFs secrete a wider range of biochemicals than their mixed cultures, thus leading to higher plant productivity.
Keywords: Biofilms, Biofertilizer, Tomato, Organic agriculture
Olax zeylanica Leaf Extract-assisted Eco-Benevolent Synthesis of Sulfur Nanoparticles and the Determination of their Insecticidal Potential against Sitophilus oryzae (L.) (Coleoptera: Curculionidae)
Authors: Sandeepani G.D.V.A.  , Perera A.G.W.U.  , Chinthaka S.D.M.  
Published: February 2024

Stored-product insects are serious pests of dried, stored, durable agricultural goods and value-added foods worldwide. In spite of the commonest way of controlling pestiferous insects associated with cereal grains and their milled products via conventional insecticides, their usage on stored grains are not recommended due to expensiveness, inefficacy due to insect resistance, and potential health hazards to humans. These deleterious consequences thus have been encouraging to merit investigation on the plant extract-assisted eco-benevolent synthesis of nanoparticles, owing to their sustainable, non-noxious, convenient, and environmental friendly nature. In view of this background, the present study was aimed at evaluating the insecticidal effectiveness of green synthesized sulfur nanoparticles (SNPs) against Sitophilus oryzae adults. SNPs have been successfully prepared from sodium thiosulfate (Na2S2O3.5H2O) in the presence of Olax zeylanica leaf extract at room temperature. The resulting SNPs were then characterized by UV-Vis spectroscopy, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). The toxicity of Sitophilus oryzae was bio-assayed by exposing the test insects to SNPs-treated rice grains at six different dosages at 1.5, 1.0, 0.5, 0.25, 0.125 and 0.0625 g/kg, whereby mortality counts were taken after every 24 hours for seven days. The UV- Vis spectroscopy showed a peak in the range of 260-280 nm, which showed the successful formation of SNPs, while being in accordance with the previous studies reported in the literature. According to the Debye-Scherrer formula of XRD data, the average crystalline size of the SNPs counted to be 72.7 nm. The particle size of SNPs is also confirmed by SEM images. FTIR results showed peak positions corresponding to S8 with slight differences due to the presence of biomolecules from the O. zeylanica leaf extract being bound onto the surface of SNPs. Bioassay results show that the mortality of insects increased with the increase of dosage and exposure time period, reporting 100% S. oryzae mortalities at 1.5 and 1.0 g/kg dosages within 7 days. Accordingly, the results of the present study thus suggest that the bio-transformed sulfur nanoparticles could be utilized not only as biocontrol agents, but also as ecofriendly candidates for the sustained-protection storage grain ecosystems from insect pest infestations.
Keywords: Green-synthesized Sulfur nanoparticles, Olax zeylanica, Insecticidal, Sitophilus oryzae
Review of the Responses of Various Soil Amendments in Sandy Soils
Authors: Jayathilini D.L.D.C  , Eeswaran R.  , Srikrishnah S.  
Published: February 2024

The primary constraints with sandy soils are low soil organic matter content, poor nutrient availability, heavy losses of applied nutrients and lower water holding capacity. Improving the productivity of sandy soils, particularly in developing countries, could be a viable solution to food insecurity and poverty. Large extent of sandy soil is one of the major constraints for crop production in the Eastern Province of Sri Lanka. Meanwhile, various soil amendments can be applied to improve the performances of cropping systems in sandy soils. Nevertheless, a comprehensive knowledge on which soil amendment would work better across different scales is not well known. To address this knowledge gap, this review was conducted using published literature. Systematic review approach was adopted, and the data were extracted from 65 highly relevant papers. The data were analyzed to calculate the percentage changes on crop yields, soil organic matter and soil carbon, in response to the applications of different soil amendments. The review highlighted the potential of several soil amendments to improve the crop performances in sandy soils. Interestingly, rice straw biochar and the municipal solid waste compost have greatly increased crop yields especially in rice at the rate of 0.9% w/w and 3% w/w in soil weight basis, respectively. Highest improvement in soil organic matter and soil carbon was observed under the applications of compost and spent grain, respectively. Therefore, rice straw biochar and compost could be evaluated to improve the productivity of sandy soils, especially in the Eastern region of Sri Lanka. Although the spent grain was promising, the availability for large scale applications may be limited in Sri Lanka. Testing of these soil amendments would require long-term experiments incorporating different crops and cropping systems.
Keywords: Compost, Biochar, Sandy soil, Soil amendments
Effect of Cinnamon Leaf Compost on Selected Soil Properties in Cinnamon (Cinnamomum zeylanicum Blume) Growing Soils
Authors: Anuradha M.D.  , Tharanga K.H.G.M.  , Dissanayake M.L.M.C.  , Madhurangi H.M.T.T.  
Published: February 2024

Integrated nutrient-management programs incorporating organic and inorganic fertilizers have been suggested to increase crop yields and reduce adverse environmental impacts in intensive agriculture. This study was conducted to investigate the effect of long-term cinnamon leaf compost (CLC) application on some selected physical, biological and chemical soil properties and the horizontal and vertical distribution of some selected soil properties in cinnamon-growing soils. The study was conducted in the National Cinnamon Research and Training Center, Palolpitiya, from January to April 2022. The experimental design was Randomized Complete Block Design (RCBD) with six treatments (T1-Control, T2-Current recommendation (CR), T3-3/4 CR with 5 t/ha/yr CLC, T4-1/2 CR with 10 t/ha/yr CLC, T5-1/4 CR with 15 t/ha/yr CLC, T6-20 t/ha/yr CLC) and three replicates. Soil samples were collected considering three horizontal distances (15, 30 and 45 cm) and with three depths (10, 20 and 30 cm). Soil physical properties (aggregate stability, bulk density, soil moisture), chemical properties (soil organic carbon (SOC), pH, electrical conductivity (EC)), and biological properties (arbuscular mycorrhizal root colonization) were determined. Water stable aggregate (WSA), SOC, and soil pH were significantly affected by the treatments, and all the variables except EC were significantly affected by the soil depth (p<0.05). Soil pH was the only variable that was significantly affected by the horizontal distance (p<0.05). Only SOC and pH have shown a significant interaction effect among treatments and depth. The application of CLC (20 t/ha/yr) significantly increases the WSA and SOC. Arbuscular mycorrhizal fungi root colonization was increased with the incorporation of CLC. Continuous application of inorganic fertilizers (T2) caused soil compaction and acidification. WSA, soil pH, and SOC were significantly improved within the 0-10 cm soil depth. The best performances of WSA, pH, and EC were shown in 30-45 cm and SOC in 15–30 cm horizontal distance from the plant base and 0-10 cm soil depth with the application of 1/2 CR and 10 t/ha/yr CLC comparison to other fertilizer combinations.
Keywords: Aggregates, Mycorrhizae, pH, Soil organic carbon
Impact of Heat on Soil Water Repellency in Forest Soils from Different Depths using Water-Repellent Japanese Cedar (Cryptomeria japonica) Forest Soil
Authors: Perera H.T.M.  , Mori Y.  , Maeda M.  , Leelamanie D.A.L.  
Published: February 2024

ome soils under plant species, such as casuarina, pine, eucalyptus, cedar, and cypress, show water- repellent conditions. Wildfires are common in forests dominated by these plant species as they produce highly flammable debris. The heat generated during wildfires alters soil characteristics, including soil water repellency (SWR). The responses of SWR to heat can differ depending on the heating temperature and the soil depth. This study aimed to examine the effects of different heating temperatures on SWR through a soil profile using Japanese cedar (Cryptomeria japonica) forest soil in Japan. Soil samples were collected from four different depths (0-5, 5-10, 10-15, 15-20 cm). Soils were exposed to heat with seven heating temperatures (TH) (50, 100, 150, 200, 250, 300, and 350° C) separately for 1 h using a programmable muffle furnace. The degree (contact angle) and the persistence of SWR in both heated and non-heated samples were measured using the molarity of an ethanol droplet test and the water drop penetration time (WDPT) test, respectively. In non-heated soils, the 0-5 cm layer showed the highest SWR (contact angle ~110°; WDPT≥3600 s). SWR decreased with depth to be non-repellent at 15-20 cm (contact angle≤90°; WDPT≤1 s). In heated samples, SWR of 0-5, 5-10, and 10-15 cm layers decreased with increasing TH, while the selection from 15-20 cm was non-repellent in all treatments. Soils of 0-5 cm depth showed extreme SWR (WDPT=≥3600 s) up to 200° C and became non-repellant at 250° C, while those of 5-10 cm showed extreme SWR up to 150° C, severe SWR (WDPT~1350 s) at 200° C, and became non- repellent at 250° C. The soils from 10-15 cm showed severe SWR (WDPT~2100 s) at TH of 50° C and became non-repellent at 100° C. Results revealed that upper soil layers with higher SWR required higher TH to become non-repellent, and soils from lower layers with lower SWR became non-repellent at lower TH. Further experiments are necessary to identify the changes in molecular levels of organic matter in response to the impacts of heat on SWR.
Keywords: Cryptomeria japonica, Laboratory heating, Soil water repellency, Wildfires
Identification of Deep and Shallow Groundwater Potential Zones using GIS Techniques; Case Study: Monaragala District, Sri Lanka
Authors: Wickramarathna R.L.  , Illeperuma I.A.K.S.  , Indrajith W.G.T.  
Published: February 2024

One of the most crucial steps in the management of groundwater sources sustainably is the delineation of the zones with potential for groundwater. However, in addition to taking a lot of time and money, groundwater investigations can be difficult and complex in many locations. To get sufficient results, it needed to demarcate shallow and deep groundwater potentiality separately. Sri Lankan districts have various problems due to a lack of water. With population growth and urbanization, surface water is insufficient to meet the water requirement. This study focused on groundwater potential mapping in Monaragala district covered with the total are 5708 km2 in Sri Lanka. The fuzzy overlay and weighted overlay method integrated with GIS were mainly used to determine potential zones for deep and shallow groundwater. The final results from the two overlaying methods were compared to identify most accurate locations. Six parameters, namely aquifer type, soil depth, soil group, rainfall, proximity to surface water bodies, and slope, were evaluated for the shallow groundwater studies. Proximity to lineament, geology and shallow groundwater parameters were assessed for profound groundwater potentiality. The final output resulting maps were categorized into five main categories such as extremely low, low, moderate, high and extremely high by considering obtained potential values. The deep groundwater potential map demonstrates that the high groundwater potential areas are located around the lineaments, prominently areas having mountain ranges. Therefore the effect of the lineament is very high for deep groundwater availability. High shallow groundwater potential areas are located in smaller regions from Katharagama, Thanamalwila and Siyambalanduwa. Obtained results were validated using existing 220 tube well data and 100 dug well data.
Keywords: Fuzzy overlay, Geology, GIS, Groundwater, Weighted overlay
Impacts of Organic and Non-Organic Cultivation Practices on Soil Fertility Parameters of Selected Paddy Lands Based on the Duration of Cultivation in Wet and Intermediate Climate Zones of Sri Lanka
Authors: Hemachandra J.K.D.S.H.  , Godakumbura P.I.  , Prashantha M.A.B.  , Cooray A.T.  
Published: February 2024

Sri Lanka has been practicing the cultivation of rice as its main staple food in two major agricultural techniques; organic and non-organic. The major aim of the present study was to analyze and compare the time duration-based impacts of the above two agricultural practices on paddy soil fertility indicators as the preliminary step of a long-term research project. Organic and non-organic paddy fields that have been cultivated for 2 seasons in Thorapitiya in the Matale district were selected as short-term cultivated lands. Land cultivated for 10 years organically in Homagama and land with a non-organic cultivation history of 20 years in Kottawa was selected as long-term cultivated lands. A total number of 35 samples were collected including the control samples from adjacent uncultivated land during the first phase of the Maha season 2021/2022. The samples were dried, sieved and then analyzed in their physical and chemical properties; color, texture, particle size distribution, pH, electrical conductivity (EC), organic carbon content (OCC), total nitrogen content (TNC), available phosphorus content (APC), exchangeable potassium content (EPC), and exchangeable magnesium content (EMC). The soil samples from Thorapitiya had a reddish-brown nature while most of the samples from Kottawa and Homagama had a grayish-brown color. Higher clay percentages were found in the soil samples from long-term organically cultivated lands in Homagama. The uniformity coefficient (Cu) values for soils from study areas except Homagama lie in the range for well-graded soil while the coefficient of gradation (Cc) values of all three areas were not in the above range. Short-term cultivation using organic and non-organic fertilizers did not show a significant difference in soil texture, pH, EC, APC, EPC, and EMC values. Most of their cultivated lands had a lower pH (~5.5–6.0) than the corresponding control plots (~5.8–6.4). The TNC levels in non-organically cultivated lands were significantly higher than in organic lands. Practicing agricultural activities for a prolonged period has resulted in significant differences in soil texture, pH, EC, OCC, TNC and APC between organic and non-organic lands. Higher OCC and lower pH, EC and APC values have been obtained for long-term organically cultivated lands than their non-organic counterparts. The TNC, APC and EPC levels were higher in most of the long- term organic and non-organic lands than in their control samples. Several amendments have to be made to bring the fertility parameters to an optimum level in long-term cultivated lands.
Keywords: Soil fertility, Paddy soil, Cultivation history, Organic cultivation, Non-organic cultivation
Spatial Variability of Selected Soil Chemical Parameters in Low-yielding Paddy Production Block in Mahaweli System H, Sri Lanka
Authors: Attanayaka A.M.S.M.  , Akther M.S.R.  , Naveendrakumar G.  
Published: February 2024

Although water availability for paddy production in Mahaweli System H is abundant, paddy yield is lower in Nochchiyagama (278 km2), chosen for soil assessment. Paddy yield data were used to identify the low-yielding division using the area-weighted average. Twenty-five random locations were generated, and soil samples were collected for pH, soil conductivity (EC), salinity, and total dissolved solids (TDS) analysis. ArcGIS software was used to create spatial distribution maps and related geostatistical analyses for each parameter. Vector files were created with their associated properties, and thematic maps were generated using spatial interpolation techniques, such as universal kriging (UK), ordinary kriging (OK), and inverse distance weighted (IDW) methods of interpolation techniques to identify the best interpolation method for soil chemical parameters mapping. The entire Nochchiyagama land was observed to have a slightly acidic pH (5.6-5.9) range that may have affected rice crop growth due to nutrient mobility and uptake issues. The spatial interpolation evaluation suggests that at least two-thirds of the area observed for lower TDS levels (591-654 mg/L) is potentially unsafe paddy production. Elevated levels of EC (3.1-7.24 dS/m) along with TDS may lead to physiological drought due to interferences in ion uptake. In overall, spatial interpolation evaluation indicators suggest that the UK method was observed with a lower mean relative error (MRE) than the other two interpolations. However, EC distribution showed low MRE in both IDW and OK interpolation techniques. The IDW method was observed to have a lower RMSE (Root mean square error). The UK spatial interpolation performed better for TDS and salinity predictions than other methods. This study found consistent regional differences in low paddy yields in Mahaweli system H using the UK method for analyzing soil chemical parameters.
Keywords: Electrical conductivity, Interpolation errors, Salinity, Spatial interpolation
Connecting the Dots; Environmental Literacy Index in Measuring Knowledge for Environmental Conservation
Authors: Dissanayake, D.M.S.B.  
Published: February 2024

Conservationist Aldo Leopold noted that acts of conservation without the requisite desires and skill are futile. Systematic environmental education plays a significant role in enhancing knowledge and competencies for environmental sustainability through a scientifically informed citizenry. The environmental education spiral consists of three key elements; environmental awareness, environmental conduct, and environmental literacy. While environmental conduct that emerged with awareness contributes to the reduction of environmental degradation, scholars argue that environmental literacy contributes to conservation. With the objective of developing an environmental literacy index, this research assessed environmental knowledge, personal conduct, and the extent of application of environmental knowledge. Key informant interviews were held to develop the index with 30 criteria, and a survey was held with 160 students in schools and universities, teachers, and development officers. Environmental literacy is seen as the individual‘s understanding and competencies that create rational and informed decisions and contributions to conserve natural systems and associated communities that create a sustainable and environmentally friendly quality of life. Environmental education can take place in many forms and is incorporated in the school education syllabus from grade one to eleven in general, and in the science stream. Among the school students, the majority (76%) were able to identify and understand age- appropriate environmental features and significance, however, had very low (13%) personal conduct for reducing pressure on the environment, while had moderate (38%) literacy levels. The average responses of the university students were 82%, 48% and 63%. Teachers, including non- science subjects teaching, had a similar status with the university students, indicating 84%, 54%, and 61%. The development officers showed slightly different patterns, representing 73%, 41% and 51%. Among all the respondents, only 13% identified agriculture practices may contribute to water pollution, 12% stated that the transport sector contributes to greenhouse gas emissions, and 9% believed that energy practices at home contribute to global warming. The study reveals that environmental understanding has not contributed much to personal behaviours to reduce the pressure on the environment, and environmental literacy has not been in a state of environmental activism.
Keywords: Environmental conservation, Environmental education, Environmental literacy
Role of Street trees in Urban Landscape: A Resource Audit
Authors: Seenapatabendige K.B.  , De Silva D.A.M.  
Published: February 2024

Street trees first considered as an ornamentation of the city landscape while brings unique identity to the city. Sri Lanka being a bio diversity hotspot large variety of trees and shrubs were available and used as part of urban landscape ornamentation. Choice of street trees based on agroclimatic zone, cultural identities, characteristics and multipurpose nature of the species. Main focus of study was to explore the role of street trees in ornamentation of cities and identify uniqueness brought to the city landscape, find out ecosystem services provided by the street trees and find out socially, culturally, economically and environmentally suitable trees species for cities located in different agroclimatic zones of Sri Lanka. Case study approach was instrumental for this study. Main data collection tools were field observations, in-depth interviews with city dwellers (45), visitors (35), officers of municipal council and urban development authority (10) and scientists (3) and policy makers (3) and maps of the cities considered for the study. Present study based on the street tree profile of 5 main cities (Colombo, Galle, Matara, Anuradhapura and Kandy), town (Bandarawela, Kaluthara, Hambantota, Rathnapura, Peradeniya and Batticaloa) and small town (Suriyawewa, Ambalongoda, Bandaragama, Mawenella, Aluthgama and Mirissa). Street trees of the main cities were ornamented by culturally imported tree species while street of the town areas was appeared with diverse mixture of trees. In Contrast economically importuned trees were common in small towns. Typology of street trees were developed using seven dimensions; social benefits, functional properties, resistant to urban environment, environmental constraints, cultural constraints and limitation constraints. 6 species were identified as the most suitable for street posadas among 15 species found in street trees. Street trees played multifunctional role in urban landscape other than its themed ornamentation role.
Keywords: Ecosystem services, Street, trees, Urban landscape