Phytolith assemblages and their implications from cal soils of Yingyang site in Dengfeng County, Henan Province

Conclusions The macro-environment of the region and the site agriculture interpreted from the phytolith assemblages at Yingyang site are as follows: i)In the mid-late period of Yangshao Culture five thousand years ago, the regional climate of Dengfeng County is warm and wet; ii)In the mid-late period of Yangshao Culture, rice farming may have been practised in the region.     

Phytolith analysis of Naminan archaeological site in Jinghong City,Yunnan Province

The global climate underwent tremendous changes during the transition from the Last Glacial Period to the Holocene. At almost the same time, human society transitioned from the Paleolithic to the Neolithic. Therefore, the relationship between climate change and human activity during this period has become a research hotspot.Yunnan Province is a region with a great abundance of Paleolithic archaeological sites in China; however, Neolithic sites are relatively few. There has also been relatively little research on paleoclimatic conditions during the Paleolithic-Neolithic transition in Yunnan. Phytoliths, as a highly durable and long-lasting form of plant microfossils, can be an important means for reconstructing paleoclimates. In this study, we examined the Naminan site in Jinghong, which was occupied during the transitional period from the Paleolithic to Neolithic. Based on our analysis of the phytolith record at Naminan, we reconstructed the climatic conditions for each of the archaeological strata and discussed possible human activities. The results show that Naminan experienced a sequence of warming followed by cooling and warming, which is consistent with previous paleoclimate research in other areas of Yunnan Province.     

Stage characteristics for the development of late Quaternary paleosols in the Yangtze Delta area

The late Quaternary paleosols in the Yangtze Delta area developed in the period of 25 000-12 000 aBP. Phytolith ratios (value A) of contents of fan, square and rectangle types indicating the warm and humid climate to those of bar, hat and point types indicating cold and dry climates decrease upwards overall on profiles of the paleosols, suggesting that the climates turned from warm and humid to cold and dry. So, the paleosols developed mainly during the regression before the last glacial maximum. Changes of value A indicate no trend of warming, suggesting that the transgression was rapid after the last glacial maximum. The development of the paleosols exhibited obvious stages, which were controlled remarkably by transgression and regression : Ⅰ . Period of alternation of deposition and pedogenesis, which was from the occurrence of regresson before the last glacial maximum to the time when sea levels fell close to the lowest; Ⅱ . Exposure period with continual pedogenesis, which was terminated when the paleosols were drown in the post-glacial transgression; Ⅲ . Period of being drown and buried, the paleosols were buried by marine sediments, and reworked by early diagenesis.     

Pollen record and environmental evolution of Caotanhu wetland in Xinjiang since 4550 cal. a BP

This paper presents a multi-proxy reconstruction of the climate change in Caotanhu wetland using pollen, phytolith and charcoal records, and the data of loss of ignition （LOI）, grain size analysis, and susceptibility. Results reveal that between 4550 and 2500 cal. a BP, a dry climatic condition was not favorable for the accumulation of peat. Since 2500 cal. a BP, the climate became humid and the wetland developed with abundant freshwater aquatic plants, which contributed to peat accumulation. Never-theless, alternate periods of rain and dry climate occurred during that period. Between 2500 and 1810 cal. a BP （550 BC-140 AD）, the climate was more humid than at present. A lot of emerged plants, such as Phragmites, Typha and Sparganium, and freshwater green algae grew in the wetland which was sur-rounded by desert-steppe vegetation composed mainly of Chenopodiaceae, Artemisia, Compositae and Thalictrum. However, from 1810 to 1160 cal. a BP （140--790 AD）, the water level started to decrease and hydrophyte species reduced greatly, but some Phragmites still grew in the wetland and around it was desert vegetation with high proportion of Chenopodiaceae and Artemisia. Then from 1160 to 650 a BP （790--1300 AD）, it entered a period of desert-steppe with abundant mesic and xerophytic plants. And a lot of aquatic plants prevailed in the wetland. Here, what is noticeable is that percentages of arboreal pollen, consisting mainly of Betula and Picea, increased greatly and reached a maximal value of 27.2%, in which, Betula percentages rose to 23.2%. Hence, it is reasonable to conclude that Betula grew in the highland of the wetland, or Picea timberline shifted downward resulting in the increase of percentages of Betula and Picea pollen, which were transported into the wetland by flood or wind. But since 650 cal. a BP, desert vegetation prevailed around the wetland again with dominant Chenopodiaceae and Artemisia, and the climate was similar to modern one. Despite some aquatic plants still growing in the wetland at     

河南邓州八里岗遗址史前稻作农业的植硅石证据

对采集子河南邓州市白庄八里岗遗址仰韶中晚期和石家河文化时期的堆积物进行了较为详细的植硅石分析，通过统计有重要意义的植石石形态类型，发现稻作农业的植硅石证据，并且，随着文化的发展（即从仰韶文化期至石家河文化期）稻作农业的强度在提高。     

Neolithic rice paddy from the Zhaojiazhuang site, Shandong, China

To identify and study the Neolithic rice paddy in Shandong, eastern China, is not only an important issue in the development of Chinese rice agriculture, but also a key part of the study on rice spread in East Asia. Due to the limitation of archaeological materials and the research methods, there have been no discoveries about the Neolithic rice paddy in Shandong Province for a long time. Based on the identification of possible rice paddy by archaeological excavation, phytolith analysis of soil samples from this "paddy" has been systematically carried out and the results have shown a 4600—4300 years old rice paddy preserved at the Zhaojiazhuang site. This is the first examination and study of the rice paddy in North China by systematic phytolith analysis, which is very important for the Neolithic archaeological research and the study of the eastward spread of rice agricultural techniques in East Asia.     

Development of ancestors'''' cultivation revealed in phytolith assemblages from Guangfulin relics

1 Survey The Changjiang Delta Region is one of the cradles of the national culture. 300 cultural sites of Neolithic, which separately belong to 4 archaeology cultural styles, includ-ing Majiabang culture (7—6 kaBP), Songze culture (6—5 kaBP), Liangzhu culture (5—4 kaBP) and Maqiao culture (4—3 kaBP), were excavated and represent the develop-ing steps of continuous ancient culture[1]. After 1949 the archaeologists in Shanghai have been doing a great deal of excavation to ancient rel…     

Complex investigation of a soil microcatena across gilgai microrelief to reconstruct environmental changes.

This paper outlines a detailed study to obtain data on the age and paleoenvironment of Vertisols in order to reconstruct the history of the landscape and soils of the North Caucasus region of south Russia. Data are from a sequence of three Vertisol pedons - the depression, the microslope, and the mound of a gilgai complex. Soils are formed on Neogene marine clays under steppe vegetation. Rradiocarbon, stable isotope, botanical and biolith data reveal the paleoecology of the region during the Holocene up to the present. The environment included a drier period indicated by humus, a warmer and wetter period indicated by carbonate nodules, and a more humid and cool period indicated by forest grass species and Comarum Pallustre. Microrelief gilgai aids for the environmental reconstructing. The soil profile in the depression supplies the most complete information. Nevertheless, it is necessary to study the whole gilgai complex to obtain full and reliable data for the environmental changes.This approach is expected to be useful for environmental reconstruction of other soils with microrelief.     

河南登封县颍阳新石器时代遗址孢粉与植硅石分析及其意义

河南登封县颖阳新石器时代遗址主要属于仰韶文化中、晚期。通过遗址剖面堆积物样品的孢粉分析和植硅石分析，获得了有关先人生活时期的古环境和文化信息，那时的气候有过多次小的波动，人类已开始了较大规模的农业生产活动，如种植水稻。     

Carbon sequestration within millet phytoliths from dry-farming of crops in China

Phytoliths are noncrystalline minerals that form inside cells and cell walls of different parts of plants. Organic carbon in living cells can be occluded in phytoliths during plant growth. It has been documented that the occluded carbon within phytoliths is an important long-term terrestrial carbon reservoir that has a major role in the global carbon cycle. Common millet and foxtail millet have become typical dry-farming crops in China since the Neolithic Age. The study of carbon conservation within phytoliths in these crops could provide insights into anthropogenic influences on the carbon cycle. In this study, we analyzed the carbon content in phytoliths of common millet and foxtail millet. The results indicated that (1) common millet and foxtail millet contained 0.136% ± 0.070% and 0.129% ± 0.085% phytolith-occluded carbon (PhytOC) on a dry mass basis, respectively; (2) based on the mean annual production of common millet and foxtail millet in the last 10 years, the phytolith occluded carbon accumulation rate of common millet and foxtail millet was approximately 0.023 ± 0.015 and 0.020 ± 0.010 t CO 2 ha 1 a 1 , respectively; (3) assuming a similar phytolith occluded carbon accumulation rate as for common millet (the highest accumulation rate was 0.038 t CO 2 ha 1 a 1 ), this could result in the sequestration of 2.37 × 10 6 t CO 2 per year for the 62.4 × 10 6 ha dry-farming crops in China. Although there was a decline in the annual production rate and planting area of foxtail millet during 1949 to 2008, the total phytolith carbon sequestration rate was 7×10 6 t CO 2 within the 60-year period. However, phytolith occluded carbon has not yet been fully considered as a global carbon sink. Also, this carbon fraction is probably one of the best candidates for the missing carbon sink.