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The critical problem of post‐burn depigmentation is the lacking normal melanocytes. Auto‐skin grafting and autologous non‐cultured epidermal cell suspension have been used to improve the appearance. However, a large amount of skin graft is required of donor sites in the former method, while the latter method is thought to be complicated and costly. This study is designed to generalise the experience of tiny epidermal particles graft (TEPG) for treating post‐burn depigmentation. From 2012 to 2013, 30 consecutive patients with depigmentation caused by burn injuries were divided into I and II group. I group: 15 cases (11 males and 4 females) were treated by the TEPG. II group: 15 patients (10 males and 5 females) were treated by suction blister epidermal skin graft (SBEG). Imagine‐Pro Plus software was used to evaluate the size of repigmentation (RP) 12 months post‐surgery. SPSS software 13.0 was used to evaluate the data. The optimum rate of RP was defined as more than 75% (RP > 75%) when excellent RP was defined as more than 90% (>90%). All patients were followed up for 12 months. The mean size of RP in two groups demonstrated that there were statistically significant differences in pigmentation between the two groups (P = 0·002), while there was no significant difference in the other factors (gender, site and age). No infection occurred in the recipient site. Pathological result showed that melanocytes existed at the basal layer of resurfacing skin. Optimum RP (RP > 75%) was seen in 12 patients in I group and 9 patients in II group. Excellent RP was achieved in 14 cases in I group and 10 patients in II group. Excellent RP can be obtained by the abovementioned two surgical techniques. In contrast to SBEG, TEPG is less traumatic, and definite effects can be guaranteed. It is a preferred treatment, especially for those patients who suffer from large depigmented lesions.

Land subsidence due to consolidation of sediment was analyzed in the Yellow River delta, using lithological data of deposits, equations of soil mechanics, and empirical relations. Subsidence in an abandoned deltaic lobe largely results from the consolidation of deltaic clay layers accumulated in the prodelta, the bays, and marine clay layers underlying the delta. The prodelta and marine clay layers have a total thickness of approximately 14 m. In the areas where thick bay-clay layers accumulated on the prodelta-clay layers, the total thickness of the clay can reach 20 m. Calculations show that after 15-m-thick deltaic strata were deposited on the seabed, the total consolidation of the 14-m-thick clay layers is approximately 1.44 m and 1.52 m for the 20-m-thick clay layers. After the first 40 years, the rate of land subsidence resulting from consolidation of the 14-m-thick clay layers will decrease gradually to 0.005 m/y. For the 20-m-thick clay layers, it will take 57 years for the rate of subsidence to decrease to 0.005 m/y.

The CC1 core, with a length of 216 cm, was drilled in the west part of the Chen Co (Lake) in southern Tibet Plateau. The210Pb and137Cs measurement indicated that it was a consecutive sedimentary sequence since ca. 1400 years. The ostracoda and their assemblages under the level of 1 cm samples’ cutting interval were finished for this core to reveal the past environmental changes in the lake area. A total of 15 species of ostracods belonging to 7 genera in the core sediments had been identified. According to the ostracod distributions, abundances and preservations in the core, seven ostracod assemblages had been distinguished. The ostracod assemblages and their ecological features, together with the sediments dating decision were used to infer the past ca. 1400 years environmental changes of the Chen Co environmental evolutions in three stages, which had responded to the Medieval Ages Warm-period (MAW), the Little Ice Age (LIA) and modern warm period. The results show that the changes of the Chen Co environment had been mainly influenced by the climatic variations. The trend of the lake level fluctuations had been accorded with that of climatic variation during the past 1400 years.

Correlation fractal analysis and R/S analysis of four indexes from Core TS95, Tianshuihai Lake, western Tibetan Plateau, FeO, Fe 2O 3, the ratio of Fe 2O 3/FeO, and organic carbon, are conducted. It is found obviously that the 4 time series are chaotic and have Hurst phenomena. The chaotic or abnormal attractors for FeO, Fe 2O 3, Fe 2O 3/FeO and organic carbon are 2.8, 3.2, 2.9 and 2.5 respectively with saturated embedded dimensions ranging from 5 to 6, suggesting that the dynamic system controlling the local climatic and environmental evolution is chaotic. It has definte variables. To establish the system, at least 3 to 4 variables, at most 5-6 variables, are needed. This generally agrees with deep sea oxygen isotope and differs by large from some climatic indexes of loess profiles. The Hurst indexes of the four proxies are FeO 0.85, Fe 2O 3 0.76, Fe 2O 3/FeO 0.65 and organic carbon 0.74 respectively, indicating that they have obviously long run dependence persistence. This is in accordance with previous studies [13-15] . The persistence results most probably from the uplift of Tibetan Plateau. This suggests that in addition to the global vacillation of climate and environment, some local factors such as the uplift of Tibetan Plateau and the change in Tianshuihai Lake drain age, have probably played a role on the proxies of climate and environment. The differences between the four Hurst indexes result possibly from the relatively easy migration of FeO that is influenced by the hydrological change of the drainage. The organic carbon and Fe 2O 3, the two of the four, are probably more suitable to extract the persistence component of environmental evolution.

The “greatest lake period” means that the lakes are in the stage of their maximum areas. As the paleo lake shorelines are widely distributed in the lake basins on the Tibetan Plateau, the lake areas during the “greatest lake period” may be inferred by the last highest lake shorelines. They are several, even tens times larger than that at present. According to the analyses of tens of lakes on the Plateau, most dating data fell into the range of 40-25 ka BP, some lasted to 20 ka BP. It was corresponded to the stage 3 of marine isotope and interstitial of last glaciation. The occurrence of maximum areas of lakes marked the very humid period on the Plateau and was also related to the stronger summer monsoon during that period.

Have been being intensively uplifted since 3.4 Ma BP, the Tibetan Plateau, with the elevation of 4000–5000 m asl,is the youngest and highest plateau on the earth. Extremely high elevation makes the plateau as the largest high-cold area in middle latitude zone. The cold climate causes permafrost to be widely distributed in most part of the Plateau while modern glaciers are developed on the high mountains above 5000–6000 m asl.Violent uplifting also causes intensive cutting which results in the formation of high mountains and deep valleys, steep slopes and higher relative relief on peripheries of the Plateau. However,it is relatively warmer and drier in dry valleys of southeastern part of the Plateau. Due to the influence of monsoon and landforms, precipitationis gradually decreasedfrom southeasttonorthwest and vegetation appearssuccession from forest todesert. Under the background of intensive tectonic movement, multiple climatic types and active landform processes, many kinds of natural hazards frequently occur in certain areas. With increasing of human activities, they also bring a series of issues to the fragile environment.

Qiangtang, which means ‘Bare land in north’ in Tibetan language, is situated in the north of Tibet, and also called as North Tibetan Plateau. From 82.5°E to 90.7°E and from 31°N to 36°N, this land extends 750–800 km along E-W direction and crosses 450 km along S-N direction. It covers an area of over 400,000 km2 that is from the Kandese-Nyqintanggula Mountains in north to the Kunlun Mountains in south and from Mt. Aludadang of the Karakorum Mountains in west to the Mt. Gar Kangri of Tanggula Mountains in east. Situated in hinterland of the Tibetan Plateau, Qiangtang is characterized with high altitude and extremely adverse climatic environment. Except for fewer herding activities, there is no permanent resident in this area. Scientific survey in this area is very weak in researches of the total Tibetan Plateau due to difficult traffic conditions for entering this area. Under this kind of background, this area is well conserved as its original situations and less disturbed by human activities (Figure 16-1).