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171.
Zhaoqi Wang Yuanhao Lin Lang Cai Guiling Wu Kai Zheng Xiang Liu Xiaotao Huang 《Land Degradation u0026amp; Development》2023,34(11):3225-3249
Soil organic carbon (SOC) is critical to the terrestrial ecosystem carbon cycle and global climate change. The carbon cycle model coupled with microbial processes can improve the projection of SOC. However, it remains unclear whether microbial models are superior to multiple terrestrial carbon cycle models and how large the simulation uncertainties of SOC are. Therefore, we simulate the spatial patterns of global SOC by the MIMICS (explicit nonlinear microbial carbon cycle model) and the DCC (implicit linear carbon cycle model), compare the SOC with that of the CMIP6 MME (multi-model ensemble) and the observation to obtain the uncertainties of SOC, and analyze the sensitivity of the parameters in the two models. The results show that the SOC simulated by the MIMICS is 1615.4 ± 54.3 PgC, which is higher than that of the DCC (668.5 ± 102.1 PgC), the CMIP6 MME (1443.7 ± 795.8 PgC), and the observation (1519.1 PgC). The SOC of the DCC and MIMICS are regulated by NPP, and that of DCC is more sensitive to climate, while that of MIMICS is mainly influenced by the Michaelis–Menten equation and microbial carbon use efficiency. We reveal the spatial patterns of uncertainty in global SOC simulated by the explicit and implicit microbial processes of multiple terrestrial carbon cycle models. Unfortunately, neither the DCC, the MIMICS nor the CMIP6 MME simulate SOC satisfactorily, especially in the high latitudes of the Northern Hemisphere, and the simulation of SOC in this region needs to be improved. 相似文献
172.
Xiaoyuan Zhang Ke Wang Gaoliang Li Jiyong Zheng 《Land Degradation u0026amp; Development》2023,34(5):1549-1557
The introduction of exotic plants with high-water consumption and high-density planting have greatly changed the deep soil water environment on the Loess Plateau of China. Slope measures can intercept runoff to change slope soil water redistribution, however, the existing measures are not enough to improve deep soil water replenishment. Infiltration holes were used as a supplement of the existing slope measures. In this study, the effects of three different measures (the control without any measures, the level ditch, and the combination of level ditch and infiltration hole) on slope runoff and deep soil water redistribution were evaluated under field conditions. The results showed that the combined measure reduced the runoff by 44.1% and the sediments by 78.6% under an intense rainfall event compared with the control. After two rainy seasons, compared with the control and the level ditch, the combined measures significantly increased the soil water storage below 50 cm in the soil layer. Combining infiltration hole with level ditch improved the deep soil water replenishment within 30 cm from infiltration hole in a horizontal plane. Overall, the single-level ditch was insufficient to improve deep soil water replenishment, and the combined measure can more effectively intercept runoff to increase the water replenishment of deep soils. Our findings provide a new thinking in regulating and utilizing slope runoff to effectively improve deep soil water replenishment in arid and semiarid areas. 相似文献
173.
Zhenhua Ma Panlong Zheng Huayang Guo Nan Zhang Shigui Jiang Dianchang Zhang Jian G Qin 《Aquaculture Research》2016,47(4):1141-1149
Jaw malformations of hatchery reared golden pompano Trachinotus ovatus larvae were studied from 1 day post hatch (DPH) to 31 DPH. The severity of jaw deformities was classified into three levels where ‘0’ represents normal jaw; ‘1’ is intermediate jaw malformation; and ‘2’ is severe jaw malformation. The severe jaw malformations of golden pompano larvae were clearly observed on 3 DPH. Starting from 3 DPH, both intermediate and severe jaw malformations were observed and the total incidence of jaw malformations ranged from 9.6% to 46.6%. The highest severe jaw malformation occurred on 5 DPH, and 25% larvae exhibited serve jaw malformation. On 11 DPH, jaw malformations reached the peak with 46.6% fish exhibiting jaw malformations of either category 1 or 2. On 26 DPH, the percentage of intermediate jaw malformation reached the peak value (36.4%). This was the first study reporting jaw malformation of golden pompano larvae, and the result can be used as a reference point for future research on the control of jaw malformation in golden pompano. 相似文献
174.
175.
本文研究了木捆排在无限水域中的运行水阻力问题,提出了排型参数(L/B)和(B/T)对木捆排运行水阻影响程度的试验数据和图表,探讨了降低木捆排运行水阻力的途径及措施。 相似文献
176.
香辛料的加工与应用研究 总被引：5，自引：0，他引：5
本文阐述了几种香辛料的加工前处理方法 ,香辛料的加工形式 ,以及姜油和大蒜精油的几种不同提取技术。 相似文献
177.
Na Wang Kang Yang Hai‐Tao Guo Jing‐Ran Wang Huan‐Huan Sun Shun‐Wei Wang Meng Sun Liang‐Zheng Sun Shun‐Li Yue Jia‐Bo Zhou 《Reproduction in domestic animals》2019,54(8):1069-1077
Spermatozoa are highly specialized cells, and energy metabolism plays an important role in modulating sperm viability and function. Rosiglitazone is an antidiabetic drug in the thiazolidinedione class that regulates metabolic flexibility and glucose uptake in various cell types, but its effects on boar sperm metabolism are unknown. In this study, we investigated the potential effect of rosiglitazone against time‐dependent deterioration of boar spermatozoa during liquid preservation at 17°C. Freshly ejaculated semen was diluted with Beltsville Thawing Solution (BTS) containing different concentrations of rosiglitazone, and the motility, membrane and acrosome integrity of sperm were detected. Besides, we measured glucose uptake capacity, l ‐lactate production level, mitochondrial membrane potential, adenosine triphosphate (ATP) content and mitochondrial reactive oxygen species (mROS) production of sperm after boar semen had been incubated with or without rosiglitazone, iodoacetate (glycolysis inhibitor) and rotenone (electron transport chain inhibitor) for 5 days. The addition of rosiglitazone significantly enhanced sperm quality and had a strong protective effect on the sperm membrane and acrosome integrity during storage. BTS containing 50 μM rosiglitazone maintained the total motility of liquid‐preserved sperm above 60% for 7 days. Rosiglitazone improved sperm quality by regulating energy metabolism manner of preserved sperm, protected the sperm mitochondrial membrane potential, enhanced sperm ATP production and in the meanwhile reduced mROS through enhancing glycolysis but not oxidative phosphorylation. The data suggested the practical feasibility of using rosiglitazone for improving boar spermatozoa quality during semen preservation. 相似文献
178.
在展优418不同生育期施用一定量的MET(多效唑)对其产量性状均有不同影响,可降低株高10％,增强植株抗倒伏能力,增加有效穗数,增产14％左右,在分蘖中期施用100g/667m~2效果最好。 相似文献
179.
Hong-Qing Ling Jianqing Niu Shuiquan Tian Shusong Zheng Xiaoli Shi Yaoqi Si Yilin He 《作物学报(英文版)》2020,(4):613-622
180.
Ma Chong Tu Qiang Zheng Shengmeng Deng Shaohong Xia Yinhang Mao Wanqiong Gao Wei Hu Lening Kuzyakov Yakov Hu Yajun Su Yirong Chen Xiangbi 《Journal of Soils and Sediments》2022,22(10):2604-2607
Journal of Soils and Sediments - Soil acidification is a major issue in agricultural ecosystems. However, how agricultural land uses shape the soil pH pattern and affect soil acidification on a... 相似文献