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The article presents a study which investigated the growth characteristics and age structure of Oxygymnocypris stewartii from Yarlung Tsangpo River in Tibet, China. The study collected 430 specimens and determined its sexes through the gonads' external appearance. Results show that during the first three years, O. stewartii grew faster compared to other schizothoracines in the same region.

Abstract  Age and growth were studied for Schizothorax waltoni in the middle reaches of the Yarlung Tsangpo River in Tibet, southwest of China, from April 2004 to September 2006. A total of 201 specimens were collected ranging from 110 to 580 mm in standard length (SL). In contrast to other otoliths, sectioned lapillus showed a clear pattern of alternating opaque and hyaline zones. Marginal increment analyses showed that the increments, each composed of one opaque and one hyaline zone, are deposited annually. Opaque edges were prevalent from May to August. The von Bertalanffy growth parameters based on sectioned otolith data were L t  = 689.8{1 − exp[0.051 (t + 3.275)]} for males, and L t  = 691.1{1 − exp[0.056 (t + 2.466)]} for females. The slow growth and long life indicate that S. waltoni is vulnerable to overfishing and that harvesting strategies for the species should be conservative. [ABSTRACT FROM AUTHOR]

Abstract: Quantifying the elevation history of the 2000km-wide Tibetan Plateau to an average elevation of 5km is important for understanding key aspects of Cenozoic global climate change, collision tectonics and the evolution of the Asian monsoon, yet quantitative measures of Cenozoic surface height change across Tibet remain few and are sometimes contradictory. Here we report the first exploratory application of a modified Co-existence Approach (CoA) using previously published fossil pollen records to reconstruct quantitatively the Cenozoic minimum palaeoaltitudes of Gangdise-Nyainqentanglha Area of the Tibetan Plateau. GCM simulations were used to adjust Eocene and Miocene raw CoA values for secular climate change and changes in palaeolatitude. This modelled correction increased the CoA-derived altitudes by 895±96m to give a minimum overall Eocene altitude of 3295–3495m. The Miocene correction factor of 481±25m gave an overall minimum altitude estimate of 3000–3150m. For the Holocene CoA returns four equally likely elevations of 4800–4950m, 3800–3900m, 3000–3100m and 2900–3000m. The first of these is indistinguishable from the present day regional average while the others suggest significant upslope pollen transport. Both the Eocene and Miocene palynologically-derived height estimates are consistent with suggestions of significant core plateau elevation by the Eocene, but are likely to underestimate the true palaeoelevation due to pre-Himalayan upslope pollen transport. [ABSTRACT FROM AUTHOR]