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La ecología y el estatus de conservación de las poblaciones de Buteo hemilasius en el altiplano tibetano son poco conocidos. Estudiamos la biología reproductiva de esta especie en 2014 en ciénagas de altura de la altiplanicie de Zoige ubicada en el suroeste de China, en el límite este del altiplano tibetano. La puesta tuvo lugar desde principios de abril hasta finales de mayo ( n = 24). El tamaño medio de la nidada (±DE) fue de 3.13 (± 0.95, rango 1-5 huevos). El número promedio de huevos eclosionados en la última visita fue de 2.54 (±1.25, rango 0-4). La tasa de fracaso fue relativamente baja (20.8%), siendo las principales causas de fracaso del nido el daño natural, las molestias humanas y la depredación. Comparados con individuos de B. hemilasius de altitudes bajas, las aves que estudiamos aparentemente pusieron menos huevos pero tuvieron un mayor número de jóvenes supervivientes, lo que sugiere que las aves de altitudes mayores pueden estar invirtiendo mayor energía reproductiva en una prole de menor tamaño para superar las restricciones impuestas por el tiempo y los recursos limitados en ambientes de elevada altitud. [ABSTRACT FROM AUTHOR]

This paper presents an in-depth analysis of urbanization dynamics on the Tibetan Plateau through the lens of Special Economic Zones (SEZs), addressing a research gap in the understanding of urbanism in highland and global south contexts. Given the current surge of assembly-based thinking within urban scholarship, we employ an assemblage framework to comprehend the heterogeneous constitution of urbanization, integrating human and non-human components, as well as socio-material, political, and spatial governances. Through a meticulous examination of three comprehensive case studies from the Tibetan Plateau SEZs, including a state-led new town, a renewable energy-driven industrial zone, and an industrial enclave, we delineate the diverse forms of plateau urbanism. Our findings underscore the imperative for contextually tailored urban development strategies that consider the distinctive geographical, ecological, and socio-political conditions of the Tibetan Plateau. It emphasizes the need for adaptive governance and planning that can address infrastructure deficiencies, environmental constraints, and the integration of local communities. Furthermore, we also call for further exploration of urbanisms in other highland regions, advocating for a more longitudinal, crosswise and nuanced understanding of urbanization processes in various global contexts. • Plateau urbanism as an assemblage of diverse plateau material and immaterial urbanization forces. • We aim to explore the interactions of various actors, diverse dynamics of spatial logics, and multifaceted spatial modes that underlie the ongoing territorial transformation of the plateau cities. • We pioneeringly applies assemblage thinking to conceptualize and empirically investigate plateau urbanism on China's Tibetan Plateau. • The study presents a comprehensive examination of three distinct Special Economic Zones (SEZs) on the Tibetan Plateau. • The paper advocates for a more inclusive and nuanced approach to urbanization processes in the lens of assemblage thinking. [ABSTRACT FROM AUTHOR]

Koucha Lake, located in Qinghai Province, north-eastern Tibetan Plateau (NETP) at an elevation of 4530 m a.s.l. Occupies an ideal position to investigate the seasonal hydroclimatic variations and related surface processes during the Holocene. We re-investigated the lake and analysed a new sediment core from the deepest part of the lake. Grain size measurements and related endmember modelling analyses (EMMA) in combination with ostracod associations together with geochemical parameters and mineral compositions from core sediments were used as relevant proxies for hydro-climatic reconstruction.A comparison of δ18O/δD from various waters on the NETP indicates a clear depleted isotopic signature of non-monsoon moisture supply in comparison to summer rainfalls, highlighting the summer evaporation for δ18O enrichment, as a reference for interpreting δ18O values from lake sediments for various situations of hydrological balance. Based on the individual core chronology the multi-proxy data indicate a very low sedimentation rate over the entire period in accordance with the catchment topography and the absence of well-developed and constant river systems, limiting the flux of sediment supply to the lake. Thus, Koucha Lake remains almost a closed system since the Lateglacial, except for the early mid-Holocene part of the sequence. The coarser particle components and their representative endmembers for spring flood and permafrost thaw between 11.9 and 10.1 cal Ka BP and from 4.5 to ca. 1.0 cal Ka BP point to lower lake levels, influenced by long winter duration with dry summer interruptions, and lighter oxygen isotopes were preserved at low evaporations. Fine-grained sediments supplied by permafrost thaw associated with activating summer surface erosion led to lake level rise between 10.1 and 4.5 cal Ka BP and during the last 1000 years, with a maximum during 7.6–7.1 cal Ka BP. Their enriched δ18O values indicate extended summer duration and concomitant evaporation enhancement, albeit a positive hydrological balance. We suggest that the interannual latitudinal shifts of the intertropical convergence zone (ITCZ) and westerly Jet and attendant varying monsoon rain belt locations are responsible tracers for the variation of the hydrological budget of the lake and the variable spatio-temporal precipitation patterns in humid and (semi) arid regions in China. • Surface processes varied interannually and between cold and warm seasons during the Holocene. • Co-existence of long cold winter and dry summer extremes at high altitudes. • Synchronous/asynchronous patterns of heat and precipitation distribution between high/low altitudes in China. • These patterns correspond to the interannual latitudinal shifts of the ITCZ and the westerly jet. [ABSTRACT FROM AUTHOR]