The definition of soil quality has always been changing over time within the soil science community. At first, the study focused more on chemical and physical properties and less importance on a sustainable environment. Therefore, the definition of soil quality has changed in the last decade. The importance of biodiversity that exists both on the surface and within the soil began to be understood. These organisms have essential functions such as nutrient cycling, provision of plant nutrients, and modification of physical soil structure, water regimes, and suppression of undesirable organisms on cropland. It has defined soil quality as the function it has within the environment, sustaining productivity, maintaining environmental quality, and promoting health in plants and animals. However, the interaction between some microorganisms is still unknown, or how it could affect the different parameters in the biodiversity of an agro ecosystem. Furthermore, it is unknown what parameters are important in determining soil quality. Therefore, this study analyzed the biological, physical, and chemical properties of the soil of two farms whose practices is different. Water retention capacity, aggregate distribution, organic matter, total nitrogen, NO₃, NH₄, and biomass of microorganisms were measured. Soils were air dried and sieved to 2mm. They were analyzed after drying in an oven at 105° C for 24 h. The biomass of microorganisms was measured by the direct extraction method. The results indicated that there was a significant difference between the microorganisms but could not be found with physical and chemical properties. This result could indicate the importance of biological properties over other parameters to discuss soil quality. In addition, the differences observed could be explained by the different practices carried out on each farm.

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Kampong Cham Province is located in plain region of Cambodia. The major activity of people in the province is agriculture, mainly cultivating rice and vegetables. More than 60% of farmers in Kampong Cham Province applied chemical fertilizers inappropriately without understanding on its impacts. The use of high rates of chemical fertilizers continuously for several years, often lead to unsustainability in production and post harmful to the environment. Recent years, with the support from the government and non-governmental organization (NGOs), many farmers realized and look for a better agricultural practice which could harmonize with natural environment and human health. Several practices were carried to promote the use of organic fertilizers such as green manures, compost, and bio-liquid fertilizer in Kampong Cham Province. The use of organic fertilizers it can reduce the input of chemical fertilizer, improve soil, water, and environment quality. Therefore, the objectives of this study are to describe farmers' practices on fertilization and discuss the effect of fertilization practices on productivity in Samraong and Baray Communes. Ones hundred farmers were selected for interview with questionnaire surveys on agricultural practices in Samraong and Baray Communes. The results from the questionnaire surveys showed that more than 70% to 80% of farmers in Samroang and Baray Communes applied organic in combination with inorgnaic fertilizers and less than 20% use only inorganic fertilizers and 10% only organic fertilizer. The amount of rice production in each fertilization practices was different, the rice production in organic fertilizer practices was high compared to other fertilization practices in Baray Commune, however, in Samraong Commune the rice production was high in chemical fertilization practices. As farmers in Samraong Commune used more chemical that is why the production was high compared to other fertilization practices.

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This study deals with the status of women who engage in agricultural practices in Kampong Cham Province, Cambodia. Specifically, it dissects the selection processes to determine which gives participant farmers access to training opportunities provided by an international non-governmental organization. The research was conducted to provide gender-disaggregated data while elucidating the gender gap that exists in opportunities for equal participation in and access to training and women's role within Cambodia's agricultural sector based on data analysis for the baseline survey and key informant interviews. This study concludes that there are specific gender roles, norms and biases, either visible or invisible, embedded and/or expected in the local community. These traits were manifested by participant farmers as well as officers who were responsible in selecting farmers. Individual interview revealed that gender norms regarding men as the head of the house and illiteracy were mentioned as two possible factors hindering women from participating in agricultural training, but when leaders who were responsible in selecting farmers were mindful about equal gender ratio, they could bring equal numbers of female participants. In order to ensure gender equality in access to skills development opportunities in the agricultural sector, trainings should focus on building effective program, and optimizing and acknowledging current female farmers' roles and contributions in the agricultural and development sector of the rural economy.

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The main object of this study was to quantitatively grasp the relevance among local farmers to analyze the characteristics of local farming and agricultural production information to build stable and sustainable farming needed by farmers. The research site was ten districts in Kampong Cham Province, Cambodia. The results of the analysis are summarized as follows: 1) It was confirmed that the index of agricultural production information varies depending on the districts; 2) Based on the Canonical Correlation Analysis results, cultivated land and annual income from agricultural activity, which are regarded to be the results of agricultural management, have relevance among factors such as attributions, crops, and agricultural production information was clarified. The cultivated land is affected by the index, which is aimed at expanding the scale of rice production. In addition, annual income from agricultural activity is affected by an index aimed at high-quality crop production based on new technology information, information about organic fertilizer and training. According to the results of the analysis, agricultural productivity expansions in Cambodia depends on providing information that can be adaptable to the intention of agricultural management of the local farmers.

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The effective use of agricultural products and the development of processed foods with guaranteed safety and quality are needed in Kampong Cham Province, Cambodia. Young papaya is an important agricultural product in this area. Dried young papaya is one of the preserved foods. The main objective in this paper was to provide basic information for the optimization of drying process. Two types of young papaya, raw or fresh papaya and blanched young papaya, were used in this study to investigate the influence of drying pretreatment that is, blanching, on the changes in the moisture content during drying and water absorption. The hot air-drying characteristics of each sample were measured at three temperatures (30, 50, and 70°C), three air velocities (1, 2, and 3 m/s), and a relative humidity of 40%. The examination of the effects of temperature, air velocity, and blanching on the drying of samples resulted in the drying characteristics of the raw sample being very similar to that of the blanched sample. A linear relationship existed in the moisture content range between the initial moisture contents and 500% (d.b.). The exponential model was applied to predict the changes in the moisture contents of samples below500% (d.b.) at each drying condition. The drying rate constants in the period above or below500% (d.b.) were increased with increasing air temperature and air velocity and expressed as a linear function of both temperature and air velocity, respectively. The water absorption characteristics of the dried young papaya and the dried blanched young papaya that were dried after blanching were investigated at three temperatures (20, 30, and 40°C). Blanching before drying of the sample had the effect of slowing the water absorption rate. The water absorption rate constant tended to increase with increasing soaking temperature.

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The After World War I, the development of the agriculture sector was delayed in contrast with the rapid growth of the industrial sector. Japanese agriculture accelerated by innovation after the economic revitalization following World War II. It clarifies the production structure of the rice production in Japan, and there is this study before the end of World War II after the First World War end during the analysis period. This study clarifies a change of factor shares of the rice production sector in this time. The purpose of this study is to elucidate the characteristics of the production structure of the rice production in Japan from 1922 through 1944, and the agriculture in Japan at this time is considered to be in a developing stage. The historic change of the rice production in Japan gives a suggestion for agriculture development in modern Asia. The measurement of factor shares of the rice production in the analysis period applies "a method to estimate land income as rest." In addition, it measures the Cobb-Douglas's type amount of production formation function. It clarify the contribution of the production input. The changes of factor shares are as follows. The change of factor shares is land, labor, fertilizer, cost of draft animals, agricultural machinery, materials, building for agriculture, seed in order of the average value from 1922 through 1944. As for the development of production technological system, it is a technological innovations land-saving and fertilizer-using. The results of estimate by the amount of production formation function are as follows. In the periods of 1922-1944, the input of the labor is excess level, the input of the fertilizer is under level and the input of the land is equilibrium level.

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Due to population growth and urbanization over two decades, Phnom Penh Capital's area has almost doubled from 375 square kilometer in 2001 to 692.46 square kilometer in 2019. Meanwhile, the number of farmers declined from 36.77% of the population in 2001 to 10% in 2015. Respecting these issues, the government of Cambodia prepared the Land use master plan of Phnom Penh City 2035. However, no clear implementation of the plan and the fast growth of construction have become the main concerns of international donors. Moreover, the integration of Phnom Penh with some areas of neighboring provinces will affect agricultural activities. Therefore, this research aims to ascertain more details of agricultural land use in Phnom Penh by responding to the Master Plan and to explain the current activities of urban agriculture or peri-urban agriculture in the capital. Owing to the pandemic, this research was conducted by solely reviewing and analyzing legal documents, reports from the government and donors, and other reliable sources. The Land use master plan clearly indicates the space reserved for the peri-urban agricultural activities; however, there are no details regarding agricultural policy dealing with the space reserved for peri-urban agriculture. The involvement of the Ministry of Agriculture, Forestry and Fisheries is also not explained. Based on the reports from donors and NGOs, lack of roles and responsibilities, limited capacity and limited finance have become the main concerns for the government regarding implementation of the Master Plan. Importantly, current rapid growth of construction does not pay any attention to the development of city plans. Housing complex projects have increased from 77 in 2011 to 178 projects in 2019. Some private businesses are practicing peri-urban agriculture on the outskirts of the capital by growing, selling some vegetables, and providing the space for the relaxation.

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In Monsoon Asia countries, rivers have intimate bonds with rural communities, which create diverse social interactions regarding community building such as recreation, education, and tourism. Especially, children tend to play around rivers, which is considered as one of the foundations of community building since playing fosters children's place-attachment to the local rivers. However, the number of children playing around rivers has been decreasing owing to expanding urbanization. This study aims to reveal 1) the influences of river use by family members and neighborhoods on children's river play, 2) the dynamics of children's social interactions in playing around rivers, and 3) the emergence mechanisms of children's social interactions in the play places. Questionnaire survey (127 local children from 9 to 11 years old), participatory observation, and hiring survey (49 local children from 9 to 11 years old) were conducted in the town of Gujohachiman, the Gifu Prefecture, Japan. Social network analysis (SNA) was applied to the observation data to examine the dynamics of social interactions in playing. As a result, river play frequency and preference of children were positively related to the frequency of daily use of rivers by their family members and neighborhoods. SNA showed that the interaction density of children playing around the river gradually increased while repeatedly fluctuating up and down. This dynamical change of interactions was caused by several leaders. The two factors for the emergence of children's social interactions were identified: introducing by the playgroup members and playing with caregivers. These results imply that rural rivers have the function for children to expand their local interpersonal relationships through playing, which are supported by local communities. Furthermore, children's play places around rivers have the potential to become the social interface for rural and urban communities.

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In Cambodia, organic rice farmers commonly engage in integrated farming and off-farm activities to supplement their income. To identify factors for income optimization, this study attempted to assess the income and expenditure structure of organic rice farm households in the Preah Vihear Province, Cambodia. Guided with a structured questionnaire, a total of 90 and 50 randomly selected farmers were interviewed in 2019 and 2021, respectively. This study utilized both descriptive and multiple regression analyses. Overall, farmers tended to expand their cultivation area and increase income from off-farm jobs. Particularly, large-scale farmers (5ha<) significantly expanded their farmland area and increased their livestock and off-farm activities, while small-scale farmers (5ha>) reduced their farmland area and increased their off-farm activities. Moreover, the multiple regression analysis revealed that secured spare time from combine-harvester usage opened opportunities for farmers to engage in off-farm jobs. These off-farm jobs, particularly by male farmers, boosted their respective annual income. On the other hand, existing loans gave several farmer respondents negative profit in 2020. Thus financial management seemed to be a factor affecting farmers’ incomes in rural areas. For further study, farm household employment choice behavior, particularly on labor mobility and off-farm activities, is recommended.

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In Tanzania, tea is considered as one of the most exported crops. The main stakeholders of the tea industry are smallholder farmers and estates. Smallholder tea farmers are required to engage in contract farming, as stipulated in the Tea Regulation of 2010. This study attempted to assess contract farming and its impact to production and income of tea smallholder farmers in Rungwe District, Tanzania. A total of 48 randomly selected smallholder farmers were interviewed using a semi-structured questionnaire in September 2020 and October 2021. Agribusiness company officials, government officials and extension officers were also interviewed to clarify the condition and issues of the contract farming scheme. Descriptive analysis and cost and return analysis were utilized. Results show that yield, income, and profitability increased from 2016-2019. These can be attributed to steady supply of inputs, easy access to technical assistance, and early adoption of new technology under contract farming scheme. Moreover, the price of smallholder green leaf has improved, with farmers receiving a second payment hence improve their overall revenue returns.

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Simple covered lagoons are used to treat wastewater from commercial pig farms in Cambodia into biogas. The electricity is generated from biogas using a generator. However, high level of H₂S corrodes or breaks down the generator. This study aims to desulfurize biogas with commercial ferrous oxide pellets (Fe₂O₃). The effects of desulfurization system on biogas production, electricity generation, and CO₂ reduction are discussed. The results show that H₂S was reduced from 2,000 ppm before treatment to around 50 ppm after treatment. CH₄ (57.7 ± 8.76%) and CO₂ (24.7 ± 2.67%) contents were not affected by desulfurization. O₂ content was changed from 0.3 to 4.8%. High O₂ level was a sign of pipe leakage, lowering CH₄ and eventually electricity production. The increase of O₂ level decreased CH₄, thus lowering generator performance. Actual electrical output power produced from biogas was 368.5 ± 29.3 kW, with loading rates of 57.6 ± 4.6% and generator efficiency of 26.8 ± 1.7%. Estimated amounts of 22,818 tCO₂equ were reduced by the biogas system. The desulfurization system was highly effective in H₂S removal without affecting biogas quality. For the long-term biogas systems in Cambodia, local-made desulfurization systems should be tested and compared with imported products.

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The Ifugao province as a mountainous land of indigenous people, described as a watershed framework that provides domestic and agricultural services. Greater portion of the province was declared as Forestland. Due to increase in population, communities tend to occupy and possess certain part of the forest to provide their basic needs. Understanding the migration characteristics on the Forestlands in the province of Ifugao may lead to a solution harmonizing the role of different stakeholders in maintaining the biological, physical and social aspect of the upland for a sustainable development. The study employed qualitative method of research and adopted the purposive sampling technique, in data gathering wherein, respondents are certified migrant in the forestlands of Ifugao province. It revealed that migration in the Forestlands in Ifugao province is being influenced by many combined factors and being prompted by poverty and aggravated by climate change. Socio-economic aspect is the primary reason why people tend occupy portion of the Forestland. They acquire portions of the Forestland as a source of living as they are engaged in farming as their main source of livelihood.

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Substantial number of rice farmer-groups are established under the promotion of group farming policies in Thailand. The groups voluntarily form joint-use funds and operate their business with them. The objective of this study is to make the model of joint-use fund management by rice farmer-groups with two approaches: 1) observing the characteristics of successful cases in the rice farmer-groups established by two policies in Northeastern Thailand; and 2) simulating a fund management on the groups based on one case group in Khon Kaen province. The case groups established funds using the resources provided by the government. Through operating the group's business, members invest in-cash or in-kind input and pay the service charges into the fund. Then the accumulated capital was used for providing returns to members' investments and scaling-up the groups' business. Based on actual accounting data of one case group, we simulated revolving joint-use fund by rice farmer-group. The result showed that the group assumed to accumulate enough amount of assets to provide sufficient service for all members using the initial fund derived from government support. A conceptual model of joint-use fund management for the rice farmers group was described. The model will be utilized to guide rice farmer-groups in developing their business and becoming independent from government support.

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One of the major successes of trade liberalization in Kenya was promotion of horticultural exports. This was aimed at reducing export earnings instability that resulted from declining commodity prices of tea and coffee. The export promotion programs put in place in the 90s paid off and horticultural exports was able to record its strongest period of growth in the 2000s. In this period the major horticulture export product was French beans in which the EU was the primarily market. However, the global markets have been changing posing new challenges of increased competition and regulatory standards which could threaten the survival and sustained participation of Kenyan horticultural exports. At the same time creating opportunities to increase export products and expand market access through transfer of knowledge, skills, and technology. For many developing countries diversification into new products and markets has been encouraged by development platforms to deal with trade related shocks that emanates from reliance of one market and a narrow range of products. Therefore, the objective of this study was to analyze the trends of product and market diversification of horticulture exports in the periods 2002 to 2019 in Kenya using UNComtrade data. We employed the Hirschman-Herfindahl index to measure product and market diversification. The study finds that the horticultural products are less diversified while the index for the market diversification showed are more diversified markets access. This shows that horticultural products have not increased instead concentrated into the same products while widening market access to other regions despite the EU markets controlling the largest share of exports. The results highlight the need to increase the export products and take advantage of untapped potential markets.

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The System of Rice Intensification (SRI) is expected to improve rice yield with minimal impact on harming environment. While many studies have confirmed that the yield increases with adopting SRI by field surveys, the impact of SRI on household income is still debatable because SRI is a labor demanding method and may cause labor redistribution within a household. This study assesses the impact of SRI on the yield, household income, expenditure and caloric consumption in Madagascar, taking into account the endogeneity between farmer's capacity and adapting technologies. The authors collect the data for small-scale rice producing households in Alaotra-Mangoro region on Madagascar central highland in 2014 and 2017 by a face-to-face questionnaire survey. The authors find that the adoption of at least one component of SRI has no significant impact on the rice yield, income, expenditure and caloric consumption of households on average compared with them that adopt none of the SRI components, taking account of the endogeneity of technology adoption. This study applies Propensity Score Matching (PSM) to take account of the endogeneity. Then, comparing mean variables with using fertilizer by using PSM, the authors confirm the positive impact on yield by plot level. However, because households can't adopt both SRI and the use of fertilizers for all plots, no significant difference is observed in household income and expenditure. The findings suggest that a combination of SRI with fertilizer inputs may increase yield significantly, if more farmers in the area start using fertilizers in the future. Provision of technical SRI training alongside sales of fertilizers is crucial. However, it is needed to conduct further research in our study site to explore the impact on the household adopted all four of the SRI components which is more effective, and long-term effects of SRI.

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Wollongong, located in the Illawarra region of NSW Australia, contains the industrial complex of Port Kembla. Lead in Port Kembla soils, ~2.5 km from a former copper smelter (1908-2003), have exceeded soil contamination guidelines for human health (HIL) and ecological (EIL) investigation levels. Previous studies regarding heavy metal contamination from the industrial complex, do not include comparisons to HIL and EIL guidelines. This study re-examines the risk of legacy (historic) heavy metals in urban soils to residents in proximity to the Port Kembla industrial complex. This was accomplished by reviewing: (i) resolution of heavy metal dispersion data from the copper smelter, in historic soil concentration data (n=95 top soil samples) collected by Jafari (2009) and reviewed by Noller (2020a); (ii) providing a new comparison of historic percentile data to current Australian soil contamination guidelines (NEPC, 2013) and German atmospheric pollutant guidelines; and (iii) re-evaluating treatments to soil data by Jafari (2009), in the context of bioaccessibility and bioavailability to humans and plants. At 75^th percentile, arsenic, cadmium, copper, lead and zinc concentrations exceeded HIL Level A guidelines. When detection limit values (52 out of 95) were removed (n=22 samples), median cadmium concentrations exceeded HIL Level A guidelines. Dietary exposure to cadmium, lead, zinc and copper is a risk to residents through the consumption of vegetables grown in urban gardens in proximity to the Port Kembla industrial complex. Copper in vegetables sampled from soils in the vicinity of the Port Kembla copper smelter was greater in comparison to sampling completed at other smelter sites. Port Kembla urban garden vegetables showed exceedance of food guidelines for both cadmium and lead, highlighting the health risks of growing vegetables in proximity to industrial areas.

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The Burdekin delta is the largest sugarcane producing region in Australia (85,000 ha) and a major coastal output to the Great Barrier Reef (GBR). Run-off from cultivation areas contain heavy metals from fertilizers, contributing to elevated Cd, Hg, and Pb in waterways. Validating the efficacy of sustainable agriculture practice is necessary to determine if current strategies protect ecosystems and uphold environmental standards. The objective of this study is to utilize Pb isotope tracing (^207/206Pb and ^208/206Pb) and elevated trace-elements (Cd, Hg, and Pb) as a monitoring tool, to detect residual heavy metals from fertilizers and alternative pollutant sources in the Burdekin catchment. Lead-isotope ratios from dry-season samples of embankment soils/sediment (n=15, 2016, 2019) and water (n=35, 2016-2020), reveals sources of natural forest soils, cane soils (fertilizer enriched), ambient dust, and historic coal fly-ash (Collinsville Power Station). Pb isotope compositions and low levels of heavy metals (soil/sediment: TCd 0.11 mg/kg, THg 0.03 mg/kg and TPb 11.02 mg/kg; estuary: THg 0.011 μg/L and TPb 4.99 μg/L) indicate that fertilizers applied to soils have minimal impact on Burdekin waterways during the dry-season, suggesting effective agricultural practice and sustainable irrigation control.

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Microbial fuel cell technology (MFCT) provides many benefits to rural regions, such as organic waste disposal and renewable energy recovery. However, its performance is low and must be improved for practical uses. Mixing steelmaking slag (SS) and lactic acid bacteria (LAB) with sediment can enhance the MFCT performance owing to LAB and iron ions dissolved from SS attaching to the electrode surface. This study proposes a simple method for attaching LAB and iron ions on carbon fiber electrode and subsequently evaluating its performance. A carbon fiber electrode was placed in a bottle containing tap water, SS, LAB, and bamboo powder (as nutrients for bacteria) for 7 days to allow LAB and iron ions to adhere to its surface. The electrode was then used as the cathode of MFCT. Results showed a decrease in the electrode potential and a consequent reduction in MFCT performance owing to the attached LAB and iron ions. The performance improved after the electrode was oxidized, suggesting that aeration is required during attachment to prevent the decrease in electrode potential. After 1 month of electricity generation, the electrode with the attachment produced high electrical current and exhibited low decrease in MFCT performance owing to electricity generation. Therefore, attaching LAB and iron ions on the electrode surface can improve the electrode performance and prevent performance degradation owing to electricity generation.

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Restoring the clear-stream environment that once existed in agricultural areas is one of the major challenges for the development of sustainable agriculture. Therefore, we analyzed the ionic components of the Rekifune and Satsunai River basins, which are regarded as clear-water basins in the Tokachi region of Hokkaido, using principal component analysis and cluster analysis based on surveys conducted in June and September 2014. The results showed that most of the sampling points in the Rekifune and Satsunai drainages were comparable to the average values of water quality assessed as clear-streams in Japan. However, in the tributaries of the Rekifune River, since Cl^- and Na⁺ increased characteristically, the water quality was degraded by anthropogenic pollution sources such as domestic wastewater. In the Satsunai River, the water quality of the downstream tributaries was degraded due to agriculture. In addition, in one of the tributaries, deterioration of water quality was observed only in September, and the water quality of the main river immediately after the inflow of this tributary was also affected. These results indicate that the water quality in the two basins in the predominantly agricultural area is generally good. Still, it is necessary to identify the source of pollution in some areas and take countermeasures.

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Hydroponic farming promotes high-efficiency water, fertilizers, and high productivity under a controlled environment. However, the use of this system needs consistent application of fertilizers, increasing the cost of operations. Molten Slag (MS), a waste from the Municipal Solid Waste Incineration has essential nutrients that can be used as fertilizer. The objective of this study was to clarify the releasing process of nutrients by molten slag to be applied as a substrate in hydroponic system. For this, anion and cation contents of three varieties of Molten Slag (MS1, MS2, MS3) were determined in the laboratory by a shaking method. The nutrient content, P₂O₅, K₂O, MgO and CaO were in MS1, MS3 and MS2. The quantification ion released was performed at 1, 6, 12 and 24 hours. It was observed that MS3 had performed the best condition in the releasing process of K⁺, Mg⁺, SO₄^2- and Cl^-. Although MS1 had higher nutrient content, MS3 released higher contents of those minerals among the samples. According to the result of this study, it was confirmed that MS3 has a high potential for hydroponic farming.

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Lao People's Democratic Republic (the Lao PDR), is naturally enriched with mineral resources having been the important potential in the country socio-economic development. Mining activities for utilizing such resource is expected to bring not only benefit but also environmental problems such as deforestation due to land opening, surface water quality decline. The objective of this study was to initially investigate the surface water quality of the two main rivers (Namkok and NamMo) near two mining areas (Sepon and PhuBia) in Savannakhet and Xaysomboun provinces, respectively. Water samples from 5 sampling sites on each river were analyzed for physical (pH, EC, temperature, turbidity, TDS,) and chemical (alkalinity, DO, COD, inorganic cations and anions, and some heavy metals) characteristics in two sampling times (May and July) in 2021. The finding results unveiled that the water of the two rivers had temperature of 23-32^oC, DO 8-16 mg/L and COD 1.8-64 mg/L. The water pH, EC, and alkalinity were found at values of 7-8, 83-576 µS/cm, and 48-174 mg-CaCO₃/L ranges, respectively. In contrast, the amount of TDS in the both rivers were 53-369 mg/L. The detected dominant cations were Na⁺, Ca²⁺ and Mg²⁺ and their concentration was in a concentration range of 0.5-34 mg/L, while main anions were F^-, Cl^- and SO₄^2- (3-9 mg/L). The particulate matter content in the water in the form of TSS (67-372 mg/L) were observed. The presence of both TDS and TSS might lead to the water turbidity of as low as 5 NTU or as high as 200 NTU. The investigated heavy metal concentration was typically low. Based on the findings, the water quality of the two rivers at the time of investigation was not beyond the Lao national environmental quality criteria.

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Predatory bug Eocanthecona furcellata was investigated for the potential of biological control agent to Plutella xylostella in the laboratory and greenhouse condition. Predation rate of 3^rd to 4^th instar nymphs E. furcellata on 2^nd, 3^rd and 4^th instar larvae P. xylostella were studied in the laboratory. The results showed that predation rate of 4^th and 5^th nymphal instars of E. furcellata were higher than 3^rd instar. Feeding rate were greater when they feed on 2^nd and 3^rd instar larvae than feed on 4^th instar larvae of P. xylostella. The efficiency of E. furcellata in controlling P. xylostella under greenhouse conditions was conducted. When P. xylostella population reached to economic threshold (ET), 20 of E. furcellata were released to chinese kale greenhouse (18 m³), Results showed that pest population was reduced 10.32% after 5 days of release when compared to control. Additionally, percentage of plant damage from released predatory bug greenhouse was lower than non-released greenhouse. Therefore, it is possible to release the predatory bug E. furcellata in vegetable production as a biological control agent.

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“Biotope” was coined in Germany by combining the ancient Greek word “Bios” which refers to organisms and life, and “Topos”, which refers to a place. In Germany, biotopes have been attracting attention since the 1970s, when environmental problems caused by industrialization became more serious. Since the end of the 20th century, biotopes have been created in various parts of Japan, including tidal flats, wetlands, lakes, rivers, and other water bodies, as well as forests and grasslands. It is still offered as an educational opportunity in Japan. They are prone to water pollution and need to be improved because biotopes are closed environmental water bodies. In Japan, there is no set environmental level for the water quality of biotopes. In this study, we conducted water quality measurement and purification experiments in the biotope in the campus at Tokyo University of Agriculture, Japan. This study aims to evaluate total nitrogen in a biotope. The biotope at Tokyo University of Agriculture had not been managed regularly for a long time. First, the filtration system installed in the biotope was not working, so it was fixed. For measuring water quality, water samples of the biotope at Tokyo University of Agriculture were collected twice a week in a month. And the concentrations of total nitrogen (TN) were measured by a spectrophotometer. In the biotope at Tokyo University of Agriculture, total nitrogen ranged from 1.14 to 3.76 mg/L, which is high compared to the environmental level set by the Ministry of the Environment for lakes and marshes in Japan. Through a set of field observation, this study attempted to improve the water quality the biotope at Tokyo University of Agriculture, which has been unmanaged for more than long years. Water quality measurement and purification experiment revealed that total nitrogen was improved.

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Most Filipinos living in remote rural and island communities rely on unsafe drinking water sources due to a lack of reliable water supply. With this, an atmospheric water generator (AWG) can become an alternative water source by condensing and collecting water vapour present in the air. However, previous research on the design of AWG devices was conducted outside the Philippines and most studies did not design the longitudinal profile of the fins and intake fan component of the device. This study designed the longitudinal fin profile of the fins and intake fan speed based on the climatic conditions of Manolo Fortich, Bukidnon and analysed the performance of the device by conducting a field experiment. The study designed the extended fins and varied the intake fan speed by conducting a parametric analysis using existing heat and mass transfer equations. The study then conducted a field experiment of the AWG device by placing the device in a secure open space. Results of the design showed that the 9 cm fin length was optimal for the device and that higher intake fan speed were more suitable for high relative humidity (RH) and high air temperature conditions. Results from the field experiment showed that higher water productivity was observed at higher RH level compared the lower RH levels. The study concludes that a longer length of copper fins and greater magnitude of intake fan speed does not necessarily translate to higher water productivity and that higher water production rates were observed during high RH levels.

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Molecular marker has been used for variety identification, genetic diversity of genotypes and additional using intellectual property protection in DUS testing. DNA fingerprinting of fourteen maize genotypes had been studied at Plant Biotechnology Laboratory, DAR, Myanmar during 2020-2021. Nine hybrids and five inbreds were analyzed using 24 polymorphic SSR markers, resulted a total number of 101 alleles with a range from 2 to 9 alleles per locus. Polymorphism has been sufficiently detected with the average of 0.66 per SSR locus. Cluster analysis separated all the maize genotypes as five major groups and indicated the existence of genetic variation among the observed inbreds and hybrids. Six SSR primer pairs (dupssr12, bnlg1940, umc1248, umc1586, bnlg1518 and bnlg1028) were selected as final marker set for variety identification with the selection criteria such as detection rate of the SSR fragment, the presence of rare allele, PIC value, and reproducibility and PCR band pattern of SSR fragments. In this study, all tested genotypes have been fingerprinted with unique profile identity (ID) to support the DNA fingerprint catalogues of Myanmar Maize Molecular DUS test guidelines.

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Botanical insecticides may offer an alternative solution for pest control. The objective was to test on the repellant, contact, and fumigant effect of the essential oils of 10 indigenous plants from Khok Phutaka Resources Protection Area, Khon Kaen Province including Limnophila aromatica, Piper sarmentosum, Clausena harmandiana, Streptocaulon juventas, Litsea glutinosa, Thunbergia laurifolia, Eupatorium odoratum, Rothmannia wittii, Ficus altissima, Clausena harmandiana and Gymnopetalum integrifolim to control the rice weevil, S. oryzae. The essential oils of plants were extracted by using hydro-distillation method and then they were tested against rice grain weevil, S. oryzae for contact, fumigant and repellent activities in laboratory condition. Adults of weevil were different tested oil at the concentrations of 0, 25, 50, 75 and 100 percentage (w/v). The maximum repellency action, 80% when L. glutinosa oil, at the concentrations of 100% (w/v) were applied for after 72 hours follow by L. aromatica (73.33%) at the concentrations of 25% (w/v) were applied for after 2 hours. The fumigant and contact test of all 10 essential oils resulted in all lower rate mortality (less than 50%), at all the concentrations.

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Pickled products made using vegetables are popular in Cambodia. Many types of homemade pickles are sold at wet markets. Our previous study showed that pickles are seriously contaminated by microbes, including food poisoning bacteria. Such contamination may depend on several factors. The objectives of this study were to investigate the levels of contaminating microbes and their growth patterns in pickles prepared according to traditional Cambodian recipes and to suggest an improved method to ensure the microbial safety of homemade pickles. Three kinds of pickles, namely cucumber pickles with or without fish sauce and bok choy pickles, were prepared following the methods used by local people. Five sample bottles for each kind of pickle were prepared to observe changes in their characteristics over time. The Brix values, salt concentrations, and pH of the samples were measured. Next, we conducted microbiological examination of the samples by testing the presence of total viable bacteria, coliforms, and fungi. More than 5.00 log₁₀ CFU/g of total bacteria were detected in all pickle samples at day 0; moreover, the number of bacteria increased until day 4. A similar concentration of coliforms was observed. Some samples tested positive for fungi. In conclusion, all samples were contaminated by harmful microorganisms that may cause food spoilage. The results of this study revealed that microbial growth occurred in all tested pickles, resulting in a high risk of food spoilage and food poisoning. We suggest that an additional step of pasteurization would help provide microbiologically safe products. Moreover, use of food additives that do not alter the taste of pickles may allow maintenance of low levels of microorganisms.

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Human population growth has led to increased energy and food production, fertilizer usage and wastewater flows. Increased nitrogen availability is a worldwide cause of eutrophication of rivers, lakes and estuaries, however, quantitative evaluation the impacts of nitrogen loads has been insufficient in developing countries because of poor data availability. The Nam Ngum River basin, Laos, which supplies quality water for domestic use in the Vientiane Metropolis, was selected as the target area for this study. The Nam Ngum River basin is 415 km long with a 17,000 km² catchment area, and the main land uses in 2000 were paddy (15.6%), forest (32.3%), shrub (40.3%) and urban (0.2%). By UN estimation, population in Laos is expected to increase 2.1 times from 2000 to 2050, and fertilizer use also will increase to produce sufficient food. Therefore, future water quality is a main concern in this river basin. Meteorological and hydrological data from 1995 to 2004, and spatial data such as topography, land use, and soil properties were collected for model simulation. A conceptual nitrogen balance model with three nitrogen pools was developed and combined with a rainfall runoff model. Simulated river discharge and nitrogen loads agreed with the observed data. Then, we investigated future nitrogen load variations in the basin under different population growth and agricultural modernization scenarios. As a result, even when population in the basin increased 2.1 times, nitrogen load did not change significantly (11,676 tons/year in 2000 and 11,822 tons/year in 2050). However, the fertilizer increase scenario, from 25 kg/ha/season to 50 kg/ha/season, showed significant increase in nitrogen loading, from 11,676 ton/year to 17,010 ton/year. Our results provide initial insight into the magnitude and spatial distribution of nitrogen loading in Nam Ngum River Basin, showing that this type of model may be useful for future impact assessments.

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Mangrove rehabilitation conducted on the seafront was a failure because of small survival due to wrong species planted and zonation. Apple mangrove (Sonneratia alba), “pagatpat,” is the most widely distributed mangrove globally, particularly in coastal regions. The study showed that the Sonneratia species bears plenty of fruits, but seedlings rarely grow in the wild. The researcher introduced a ninety-day analysis using various soil media and different watering regimes in a designed concrete tank to determine the survival and growth rates of the nursery propagated apple mangrove seedlings. He observed that the highest average survival rate of S alba seedling was in watering regime Treatment 3 and the type of soil medium was sandy clay. The researcher measured the average survival rate at 23.70% in clay, 52.10% for sandy clay, 44.32% for sandy soil under a watering regime, 37.41% in clay, and 43.21% in sandy clay, and 39.41% in sandy soil. Research showed that the seedlings watered under Treatment 3 observed the highest growth gain (5.41 ± 0.68 cm), while seedlings under Treatment 1 recorded the lowest growth gain (1.87 ± 0.23 cm) under the watering regime. Seedlings planted in sandy-clay soil exhibited the highest growth gain (4.15 ± 0.52 cm), while seedlings planted in clay recorded the lowest growth gain (4.0 ± 0.50 cm) for soil media. Moreover, the researcher observed that growth showed a significant difference in the different watering regimes but had no significant difference in the type of soil media.

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