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Abstract: This paper investigates changes in the vegetation and hydrology at Ljubljansko barje (Slovenia) using a multi-proxy approach (pollen, diatoms, geochemical and stable isotope analysis). During the Lateglacial Ljubljansko barje was a deep, oligotrophic lake surrounded by open woodland comprised predominantly of Pinus and Betula which in the early Holocene, when the lake became shallower and mesotrophic (Fragilaria pinnata, δ 15N~3.3‰, δ 13C~−33.7‰, C/N~7.9), was replaced by broadleaved tree taxa (Tilia, Ulmus, Quercus, Corylus) and Picea. This was followed by the spread of Fagus and after ~9200 cal yr BP Abies and planktonic and oligotrophic diatom taxa (Aulacoseira italica, Gomphonema angustum) as well as an increased allochthonous influx (silt, SiO2, Al2O3). Between ca. 6750 and 6000 cal yr BP the diatom data suggest shallower and oligotrophic conditions, whereas the stable isotope record (increased δ 13C and decreased δ 15N) indicates terrestrial input. Changes in forest composition (increase of Quercus, Alnus, Corylus) and the spread of herb taxa were probably advanced by human impact on the environment. The beginning of organic sedimentation, dated to 6000 cal yr BP, was followed by an increase of Fagus and Abies and by eutrophication and peat growth at ~5200 cal yr BP. [Copyright &y& Elsevier]

Abstract: This paper explores some of the new perspectives resulting from re-examination of the pollen data from my 1978 comprehensive analysis of 100 coprolites from one of the earliest identified prehistoric latrines in North America. Of particular interest are the empirical results of previously unavailable pollen concentration calculations for some of the prehistoric specimens as well as a time-series of 82 modern fecal specimens produced during an experiment yielding data on the rate of elimination of specific pollen grains from the human system. Experimental data of all sorts are needed to extend coprolite analyses and interpretations, particularly from pollen-ingestion studies conducted with more volunteers over long periods of time. Parasitological studies of human coprolites will benefit from experimental data to determine the fate of the constituents of human feces ingested by dogs. The application of specialized techniques at the microscope, such as Intensive Systematic Microscopy ([Dean, G., 1998. Finding a needle in a palynological haystack. In: Bryant, V.M., Wrenn, J.H. (Eds.), New Developments in Palynomorph Sampling, Extraction, and Analysis. Am. Assoc. of Stratigraphic Palynologists Foundation., Contribs Series No. 33, pp. 53–59]), to locate and quantify rare pollen types needs to be explored. Easy and useful ways to express the abundance of macroremains in a coprolite are also needed. [Copyright &y& Elsevier]