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The Qaidam Precambrian block is located in the northeastern Tibetan Plateau and was intruded by numerous Ordovician-Devonian granitoids during and after the closure of the Proto-Tethys Ocean. In the past 20 years, the granitoids within early Paleozoic subduction-collision belts have been investigated in detail. However, the granitoids intruding the inner part of the Qaidam block, bearing the tectonic significance for the whole block, still need to be understood. This study presents new whole-rock geochemical and zircon U-Pb-Hf isotopic data for the Huatugou granitoids in the Qaidam Precambrian block. The investigated granitoids include granodiorite, monzogranite, biotite granite, and muscovite granite, which intruded the Precambrian basements during 451–400 Ma. The granodiorites (451 ± 6 Ma) display adakitic geochemical features and syn-tectonic textures, and their magmas were generated by the partial melting of the lower mafic crust within a thickened continent. The muscovite granites (410 ± 6 Ma), with negative zircon εHf(t) values of −14.5 to −10.4, were crystallized from fractionated S-type magmas, which were derived from the partial melting of ancient crustal materials. The biotite granite (410 ± 3 Ma) and monzogranites (400 ± 4 Ma) are high-temperature A2-type granites. The biotite granite displays positive zircon εHf(t) values of +1.7 to +5.6. Its magma was generated by the high-temperature partial melting of juvenile crustal rocks in a thinned lower crust. The monzogranites exhibit higher SiO2 contents and lower εHf(t) values, and their magmas were derived from the same source but underwent assimilation and fractional crystallization during emplacement. From the thickened to the thinned continent during 451–410 Ma, the western Qaidam block experienced a tectonic transition from compression to extension. Combined with regional geological data, this study suggests that the Qaidam block consisted of the thickened continental crust during subduction processes until the detachment of the subducted slab during the continental collision. The regional extension of the Qaidam block commenced at ∼420 Ma, soon after the exhumation of ultrahigh-pressure metamorphic rocks within the northern Qaidam subduction-collision complex belt.

Improving resource use efficiency is an effective way to accelerate the realization of “carbon emission peak” and “carbon neutrality.” To perform a thorough analysis of the temporal and spatial variations in Zhejiang’s agricultural sustainable development, the present study adopted the entropy weight TOPSIS method and built a RUE-based evaluation index system for sustainable agriculture. The system covered six evaluation aspects: agricultural resource endowment, the agricultural production and agricultural science and technology levels, and ecological, economic, and social benefits. Based hereon, the present study evaluated the agricultural sustainable development of Zhejiang province from 2013 to 2019, and that of its 11 prefecture-level cities and 25 national agricultural sustainable development pilot demonstration zones in 2019. The results showed that chronologically, Zhejiang made steady progress in its agricultural sustainable development from 2013 to 2019, despite slight fluctuations, and spatially, evident regional disparities were found across its 11 prefecture-level cities and 25 pilot demonstration zones. Moreover, resource use efficiency had a significant impact on agricultural sustainable development. Zhejiang’s practices in the efficient use of cultivated land, water resources, forest resources, agricultural labor force, agricultural material goods, and agricultural science and technology offer valuable references for sustainable agriculture worldwide.