To understand grain size evolution on the lunar surface in detail, we analyze the distribution of the average grain size for the lunar near side obtained by Jeong et al. Furthermore, we analyze the polarimetric properties of the regolith simulants SiC and JSC-1A in a laboratory. We find two characteristics of grain size evolution on the Moon. First, the lunar regolith has evolved on a specific evolutionary pathway in space. Here, Φ is defined as the ratio of the perpendicular ( ) and parallel ( ) components of the reflectance. Second, we also find that the evolutionary pathway depends on the FeO abundance and selenographic latitude of the surface. The dependence on the FeO content seems to result from the different resistance to comminution of regolith materials, and the dependence on the latitude seems to result from differences in the resurfacing environment. We present the probable causes of these characteristics of grain size evolution on the lunar surface.

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<p>Global production of plastics has steadily increased since 1950s. As a result, plastics are the most abundant type of marine debris on seafloor and coastal beach, and the prevalence of marine debris has detrimental impact on marine wildlife. The Convention on Biological Diversity (CBD, 2012) estimated that over 80% of adverse environmental impacts on marine life are associated with plastic debris. It is important to build up information on the amount and characteristics of plastic debris that damage marine species to devise strategies and set priorities to reduce their adverse impacts on marine life. This study investigated plastic debris ingested by sea turtles stranded, floating, or by-captured from 2012 to 2022 in the Korean coastal waters. The quantity, shape, color, size, origin, and polymer type of plastic debris (> 1 mm) ingested by sea turtles were analyzed after being sorted from gastrointestinal (GI) tract of 71 turtles: 41 loggerheads, 24 greens, 3 leatherbacks, 2 olive ridleys, and 1 hawksbill turtle. We found a very high frequency of occurrence of plastic debris in GI tract of sea turtles; 100% for greens, 83% for loggerheads, 67% for leatherbacks, 50% for olive ridleys, and 100% for hawksbill. The overall amount of plastics were in the range of 0－1.31 g/kg turtle (0－229 pieces/turtle). The ingested debris tended to be films and fibers (> 74%), light in color (white and transparent; > 60%), and light polymers (polyethylene, polypropylene, polypropylene[poly(ethylene:propylene)], expanded polystyrene; > 90%). Single-use or fishery-related plastics such as filmed packaging, plastic bags, twine, net, and rope were frequently found. Some debris were labeled with Korean (n=14), Chinese (n=10), English (n=2), and Vietnamese (n=1). The shape and origin of ingested debris varied between loggerhead and green turtles. Green turtles ingested commonly fibers (47%) such as rope, twine, and net. Conversely, loggerheads ingested frequently films (45%) such as plastic bag, and packaging. The difference in ingested plastics between greens and loggerheads may be related to feeding habit and geographical range of movement of each species. This study implies that sea turtles inhabiting around the Korean waters are severely affected by marine plastic debris, and that waste management of single-use and fishery-related plastics should be the top priority to effectively reduce the adverse impact of plastic debris on sea turtles.</p>

To determine the movement patterns, home range, and use of structural features of captive-bred one-or two-year-old Amur ratsnake (Elaphe schrenckii) juveniles in the natural habitat, we radio-tracked a total of 11 juvenile snakes in a mountain valley in Chiaksan National Park, South Korea, between August 21 and September 20, 2010 and between June 13 and July 13, 2011. During the first week of the release, most juveniles moved short distances, daily, but they increased their distances after the first week. The body weight of the juveniles was negatively related with the movement rate (dividing the number of movements by the number of relocations), which was positively related with the mean daily distances moved and the size of both a kernel 50% and 95% home range. During the study period, the juveniles moved daily, approximately 17 m, and the size of the minimum convex polygon and the 50% and 95% kernel home ranges were 1.8 ha, 0.4 ha, and 3.0 ha, respectively. The released captive-bred juveniles were more frequently confirmed underground or on the ground rather than on rocks or on trees. Our results suggest that the body condition of released individuals, the seasonal time of the release, and the existence of available prey and shelters in the habitat should be carefully considered when releasing captive-bred Amur ratsnake juveniles for the rehabilitation of field populations.