Evaluation of the effects of transplanting date shifts and drainage outlet raising management practices in paddy farming regions under future climates using coupled APEX-Paddy and SWAT models

Paddy and Water Environment - Predicting adaptation and the response of agricultural water resources to climate change is a challenging. As changes in future climate will change agricultural...     

APEX-Paddy model simulation of hydrology,total nitrogen,and rice yield for different agricultural activities in paddy fields

Paddy and Water Environment - Existing agro-hydrological models to explore the effects of paddy management practices on hydrology and water quality suffer from multiple shortcomings because they...     

In vitro development of canine somatic cell nuclear transfer embryos in different culture media

The objective of the present study was to investigate the effects of three different culture media on the development of canine somatic cell nuclear transfer (SCNT) embryos. Canine cloned embryos were cultured in modified synthetic oviductal fluid (mSOF), porcine zygote medium-3 (PZM-3), or G1/G2 sequential media. Our results showed that the G1/G2 media yielded significantly higher morula and blastocyst development in canine SCNT embryos (26.1% and 7.8%, respectively) compared to PZM-3 (8.5% and 0%) or mSOF (2.3% and 0%) media. In conclusion, this study suggests that blastocysts can be produced more efficiently using G1/G2 media to culture canine SCNT embryos.     

Runoff simulation considering the effects of hydraulic structures on agricultural water uses

For the efficient management of water resources in the target basin, this study proposed a method to improve the reliability of a long-term hydrological simulation model by applying to the model agricultural water more approximate to actual water uses (than planned water demands) through their adjustment based on the effects of small-scale hydraulic structures. To verify agricultural water uses estimated using the proposed method, they were applied to a basin management model. And then, simulated runoff at main station points was compared with measured runoff. As a result, there occurred errors with large differences from measured data, mainly, at station points where their dependency on river water was high. To verify simulated return rate, return rate for a test zone was estimated, and then compared with the simulated return rate. Correlations between annual rainfall and runoff errors were analyzed. As a result, it was found that those errors were enlarged in dry years. Long-term runoff simulation analysis showed that simulated runoff came to be negative when a farming season began. This could be significantly improved using water uses adjusted to consider the effects of small-scale hydraulic structures. Also, correlation analysis quantitatively confirmed that simulated runoff after adjustment was more correlated with measured runoff than before adjustment. Finally, fitness tests for runoff simulations before and after adjustment were carried out through a residual analysis to analyze residual normality and independence. As a result, the fitness of runoff simulation after adjustment was significantly improved.     

Evaluating impacts of climate change on hydrology and total nitrogen loads using coupled APEX-paddy and SWAT models

Paddy and Water Environment - Climate change is currently one of the most critical issues in watershed management, and typical paddy systems should be addressed by watershed modeling approach in...     

Population genetic structure of Raffaelea quercus-mongolicae indicates a recent fungal introduction event to Jeju Island from inland areas of South Korea

Raffaelea quercus-mongolicae, a mycangial symbiont of a wood-boring ambrosia beetle, Platypus koryoensis (Coleoptera: Curculionidae: Platypodidae), has been associated with the mass mortality of Korean oak trees in South Korea. Systemic wilt from the inoculation of oak trees with R. quercus-mongolicae has caused significant damage to forest ecosystems in the country. Despite the continued spread of this fungus across the country since the first discovery of the disease, little is known regarding its biology. During a recent survey carried out to investigate the status of oak wilt diseases on Jeju Island, South Korea, visible signs of bark beetle attack, including bark beetle frass and galleries, were consistently observed in Quercus serrata, and R. quercus-mongolicae was successfully recovered from the trees. To determine whether the pathogen was introduced from inland areas of the country to Jeju Island, the genetic diversity and population structure of R. quercus-mongolicae isolates collected from various geographical regions and hosts in the country were investigated using a combination of eight microsatellite markers designed from the genome of the fungus in this study. The results showed lower levels of genetic diversity for the population from Jeju Island compared to those from inland areas of the country. This suggests that a limited number of individuals were recently introduced to Jeju Island, resulting in a new disease problem in the area.