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This study presents high-resolution pollen and charcoal records from Guxu Lake in the Taihu Lake Basin, eastern China, spanning the last 23,000 years. The sedimentary sequences revealed dynamic terrestrial and lacustrine environments during 23.0-11.7 cal ka BP, the climate was relatively cold and dry, and the vegetation was dominated by evergreen-deciduous broadleaf and coniferous mixed forest. During 11.7-4.4 cal ka BP, the Quercus- and Castanopsis-dominated evergreen-deciduous broadleaf mixed forest expanded, while the Poaceae and Artemisia were still the major terrestrial herbs under warmer and more humid conditions. After this period, the climate became relatively cool and dry again, and the vegetation landscape was comparatively stable, as it remains today. Wild rice likely grew before Neolithic humans occupied this area. The variations in Oryza-type Poaceae pollen spectra and distributions of Neolithic archaeological sites indicate rice agriculture may have first appeared and developed with human occupation in ca. 7.0-4.4 ka BP. During the historical period, beginning approximately 4 ka BP, a clear signal of intensified anthropogenic disturbance is evident from the clearing of forests, high charcoal concentrations and the presence of rice pollen in large quantities. These results suggest more intensified rice farming was widespread, with increasing human impact on the environment.

Phytolith analysis was conducted on soil samples from an archeological profile at the Hehuashan site, located in the upper Qiantang River region, China. This paper focuses on: (1) changes on the morphometric features of Oryza-type bulliform phytoliths from the rice leaves of the Early Neolithic Hehuashan site, (2) human adaptations during the Early Holocene, and (3) the cultivation of rice by Early Neolithic occupants in the upper Qiantang River region. The phytolith assemblage before and during the Early Neolithic Shangshan Culture occupation of the Hehuashan site indicates a landscape composed of reeds (Phragmites australis), rice (Oryza sp.), Bambusoideae, and some woody plants. The amount of Oryza-type bulliform phytoliths and the number of scale-like decorations present along their margins increased from the lowest to the uppermost deposits at the site. The change in the amount and morphology of bulliform phytoliths indicates the presence of wild rice around the site at the time of human occupation, which provides evidence of a shift from the collection and possible manipulation of wild rice to cultivation during the Shangshan Culture period (11400–8600 BP).

A new instrument, the Polarized Scanning Nephelometer (PSN), has been developed for measuring the complete scattering matrix of aerosol particles as a function of the scattering angle. The instrument measures directly the ensemble-averaged scattering matrix elements of the aerosol particles and can deduce all scattering matrix elements for scattering angles in the range 3.5° to 170° at two different wavelengths (445 nm, 633 nm). The PSN instrument features a number of different optical components including beamsplitters, polarizers, and quarter-wave plates. By using different combinations of orientation angles for the optical components, all the scattering matrix elements are obtained as a function of the scattering angles. Nitrogen gas was used to give a measure of the stray light suppression level of the instrument. Instrument performance in terms of the accuracy of the scattering matrices was verified quantitatively using homogeneous polydisperse spherical particles. For instance, in studies comparing the PSN measurements with Mie calculations, the average absolute relative errors of the scattering matrix elements for diethylhexyl sebacate (DEHS) droplets were within 0.02 and 0.025 at 445 nm and 633 nm, respectively.

Floatation of archaeological remains from sediments of the Neolithic Zhumucun site, attributed to the Liangzhu Culture (5300–4300 BP), demonstrates the diverse plant resources available at this site. The plant remains suggest a generally warm and humid wetland landscape where rice-based subsistence was possible. Domesticated rice was cultivated in paddy fields and served as the only cereal, while some melons and fruits, such as muskmelon (Cucumis melo) were probably cultivated as well. In addition, some species of Polygonum might have been utilized as vegetables. Furthermore, herbs such as Potentilla sp., Zehneria indica, and Lagenaria siceraria var. microcarpa were probably collected for medical purposes.

According to archaeological investigation and preliminary excavation, the Yangjia Site, located in the northern Taihu Lake region, at Wuxi City, Jiangsu Province, is a Neolithic archaeological site dominated by cultural remains attributed to the late Majiabang Culture (6270–5920 cal. a BP). Here a systematic archaeobotanical study was conducted to investigate vegetation landscape, environmental characteristics and rice agriculture in the prehistoric northern Taihu Lake area. The abundance, frequency and standard density of charred rice were the highest of all of the remains of the seed plants unearthed. In addition, a variety of wetland weeds, such as Haloragaceae, Cyperaceae, Carex sp., and Oxalis corniculata, were found. Pollen and phytoliths recorded that the evergreen-deciduous broadleaf mixed forest (represented by Quercus and Castanopsis) tends to decrease, while Poaceae was the most significant of the terrestrial herbs, water area expanded and water activities strengthened, indicating generally warm and humid conditions at the Yangjia Site during the late Majiabang Culture. All indicators of pollen, phytolith and macro-plant remains suggest that wild rice should be once distributed at or around the site before human occupation, after which rice agriculture progressed rapidly during the late Majiabang Culture.