Soil erosion causes land degradation which negatively impacts not only natural resources but also livelihoods of people due to low agricultural productivity. Cambodia is prone to soil erosion due to poor agricultural practices. In this research we use Battambang province as a case study to quantify impact of land use and land cover change (LULC) on soil erosion. This study assessed the impact from LULC changes to soil erosion. LULC change maps were analyzed based on Landsat satellite imagery of 1998, 2008, and 2018, computed in QGIS 6.2.9, while the soil erosion loss was estimated by the integration of remote sensing, GIS tools, and Revised Universal Soil Loss Equation (RUSLE) model. The results showed that the area of agricultural land of Battambang province significantly increased from 44.50% in 1998 to 61.11% in 2008 and 68.40% in 2018. The forest cover significantly decreased from 29.82% in 1998 to 6.18% in 2018. Various soil erosion factors were estimated using LULC and slope. Based on that, the mean soil loss was 2.92 t/ha.yr in 1998, 4.20 t/ha.yr in 2008, and 4.98 t/ha.yr in 2018. Whereas the total annual soil loss was 3.49 million tons in 1998, 5.03 million tons in 2008, and 5.93 million tons in 2018. The annual soil loss at the agricultural land dramatically increased from 190,9347.9 tons (54%) in 1998 to 3,543,659 tons (70.43%) in 2008 and to 4,267,439 tons (71.91%) in 2018 due to agricultural land expansion and agricultural practices. These losses were directly correlated with LULC, especially agricultural land expansion and forest cover decline. Our results highlight the need to develop appropriate land use and crop management practices to decrease land degradation and soil erosion. These data are useful to bring about public awareness of land degradation and alert local citizens, researchers, policy makers, and actors towards land rehabilitation to bring the area of land back to a state which is safe for increasing biodiversity and agricultural productivity. Measures to reduce or prevent soil erosion and the use of conservation agriculture practices, along with water and soil conservation, management, agroforestry practices, vegetation cover restoration, the creation of slope terraces, and the use of direct sowing mulch-based cropping systems should be considered.

The main objective of this research was to evaluate land use and land cover (LULC) change in Battambang province of Cambodia over the last two decades. The LULC maps for 1998, 2003, 2008, 2013 and 2018 were produced from Landsat satellite imagery using the supervised classification technique with the maximum likelihood algorithm. Each map consisted of seven LULC classes: built-up area, water feature, grassland, shrubland, agricultural land, barren land and forest cover. The overall accuracies of the LULC maps were 93%, 82%, 94%, 93% and 83% for 1998, 2003, 2008, 2013 and 2018, respectively. The LULC change results showed a significant increase in agricultural land, and a large decrease in forest cover. Most of the changes in both LULC types occurred during 2003–2008. Overall, agricultural land, shrubland, water features, built-up areas and barren land increased by 287,600 hectares, 58,600 hectares, 8300 hectares, 4600 hectares and 1300 hectares, respectively, while forest cover and grassland decreased by 284,500 hectares and 76,000 hectares respectively. The rate of LULC changes in the upland areas were higher than those in the lowland areas of the province. The main drivers of LULC change identified over the period of study were policy, legal framework and projects to improve economy, population growth, infrastructure development, economic growth, rising land prices, and climate and environmental change. Landmine clearance projects and land concessions resulted in a transition from forest cover and shrubland to agricultural land. Population and economic growth not only resulted in an increase of built-up area, but also led to increasing demand for agricultural land and rising land prices, which triggered the changes of other LULC types. This research provides a long-term and detailed analysis of LULC change together with its drivers, which is useful for decision-makers to make and implement better policies for sustainable land management.

Fish are one of the main sources of protein in Cambodia but they are highly perishable. This requires immediate consumption or processing for later use. In processing, fish drying is very common, but most processors practice traditional drying methods although solar dryers have been introduced, or gradually used, in Cambodia. There is a large variation in terms of drying efficiency due to large differences in solar radiation, temperature, and humidity conditions in traditional drying methods and solar dryers. However, there is limited information on the actual variation in these two systems, which should be documented in Cambodia. Using sensors to monitor micro-climatic changes inside the drying chamber will be useful to improve efficiency and performance. Therefore, the objectives of this research were to (1) design a fish dryer from locally available inputs; (2) determine changes in solar radiation over time; (3) compare relative humidity and temperatures between traditional sun-drying and the solar dryer; (4) determine the relationship among the climatic parameters; and (5) compare some physical, chemical, and biological properties of dried fish in both drying techniques with the Cambodian dried fish standards. The study was conducted in collaboration with a fish processor in the Siem Reap Province between December 2023 and January 2024 using a sensor-mounted solar dryer fabricated by the Royal University of Agriculture to dry fish and compared with traditional sun-drying. Three experiments were carried out from 8:00 to 16:00 following the common drying practices in Cambodia. In each experiment, 80–100 kg of raw giant snakehead, or 56–70 kg of prepared fish (1.04 ± 0.05 kg each fish), was prepared for drying. Data on environmental conditions were measured and analyzed. The results show that the solar dryer had higher temperatures (almost 60 °C) and lower relative humidity (about 20%) during peak hours when compared with traditional sun-drying (36.8 °C and 40%, respectively). In all cases, relative humidity decreased with rising solar radiation and temperatures. The final weight and moisture of dried fish in the solar dryer were lower than those in traditional sun-drying in eight hours. Salmonella was detected with traditional sun-drying but E. coli was not. Bacterial presence may be harmful to human health. Nevertheless, the time spent for drying in both techniques was the same, so future studies should focus on improving ventilation to remove moisture faster out of the solar dryer, which can help with faster drying and more time saving. Hybrid solar dryers should also be considered to maintain high temperatures at night, while bacteria should be counted for safety reasons.

This study analyzed land use and land cover (LULC) change from 1998 to 2018 in Battambang, Cambodia, and determined factors and constraints affecting agricultural production. Landsat satellite images in 1998, 2008, and 2018 were used to identify the changes in LULC. In combination, a social survey was conducted in August 2021 using purposive sampling, selecting a total sample of 200 from two wealth classes: the poor (65) and the better off (135) based on the Cambodia poverty assessment by the World Bank, from uplands to lowlands of Battambang Province, Cambodia. Household characteristics, farm size, and constraints were compared between the classes. T-tests, the analysis of variance (ANOVA), and Likert scale analysis were adopted using the R Program and RStudio, while Pearson's correlation test was used to determine the factors affecting agricultural land. The results show that between 1998 and 2018, the forest cover decreased by 79%. In contrast, agricultural land expansion was the highest (54%). The average household size and age of the respondents were 5.0 persons/household and 50.1 years, respectively. Of all the interviewees, about 80% attended no higher than primary school. The total farm size of the better-off (7.0 ha/household) was larger than that of the poor (5.2 ha/household). The population growth, machinery use, and improved infrastructure were found to be positive and strongly related to agricultural land use. The highest constraints of the poor and the better-off households were the same: chemical fertilizer use. Then, drought and flooding were also challenges for all. In terms of land, credit, and labor, they were not the main constraints. Thus, it is recommended that the involvement of interdisciplinary stakeholders and policy frameworks is really important from both biophysical and social perspectives.