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Copyright of Journal of Forest & Environment is the property of Journal of Forest & Environment Editorial and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The forest ecosystem in Yuyang District is in the primary succession stage of vegetation construction in the new period. The study of the change characteristics and influencing factors of soil organic carbon storage under different vegetation types is conducive to the restoration of forest ecosystems and the rational use of land. Taking five typical vegetation in Yuyang District as the research object, the content of organic carbon in different soil layers was measured, and the storage characteristics of soil organic carbon in 0-100 cm of different vegetation types and their relationship with soil environmental factors were discussed. (1) Under different vegetation types, the average content of soil organic carbon was Pinus tabulaeformis forest(5.62 g·kgkg–1) > Pinus sylvestris forest(4.13 g·kgkg–1) > Platycladus orientalis forest(3.44 g·kgkg–1) > Hippophae rhamnoides forest(2.75 g·kgkg–1) > grassland(1.37 g·kgkg–1), The average content of soil organic carbon in Pinus tabulaeformis forest was significantly different from that in Platycladus orientalis, Hippophae rhamnoides forest and grassland (P < 0.05). (2) The soil organic carbon storage of different vegetation types ranged from 21.08 t·hm–2 to 76.16 t·hm–2. (3) The correlation between soil organic carbon and soil physical and chemical properties was different in various vegetations. From the perspective of the five types of vegetation, organic carbon and electrical conductivity were extremely significantly positively correlated (P < 0.01), which was related to total porosity and total porosity. The saturated water content was significantly positively correlated (P < 0.05). The storage characteristics of organic carbon under different vegetation types in Yuyang area were different, and the electrical conductivity, total porosity and saturated water content significantly affect the accumulation of soil organic carbon in woodland. [ABSTRACT FROM AUTHOR]

Copyright of Science Technology & Engineering is the property of Chinese Society of Technology Economics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Geoscientica Sinica is the property of Acta Geoscientica Sinica Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Nonferrous Metals (Mineral Processing Section) is the property of Beijing Research Institute of Mining & Metallurgy Technology Group and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Prataculturae Sinica is the property of Acta Prataculturae Sinica Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Forest & Environment is the property of Journal of Forest & Environment Editorial and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

To study the characteristics of soil moisture deficit under different vegetation types in a water-wind erosion crisscross area, this study chose six typical forests( Populus simonii, Armeniaca sibirica, Amygdalus davidiana, Caragana korshinskii, Populus hopeiensis, and Hippophae rhamnoides) in Wuqi County, Yan' an City, Shaanxi Province, as the research targets. Based on an analysis of the dynamic change characteristics of forest soil moisture, the study aimed to provide a basis for high-quality and sustainable development of water and soil conservation in vegetated areas. The results showed that the soil moisture in the 0-300 cm soil layer of the six forest lands exhibited significant vertical variation. It first increased and then decreased as soil depth increased. The soil moisture of each soil layer in the six forest lands exhibited clear seasonal variations. The top soil layer exhibited a high coefficient of variation, and this coefficient decreased as soil depth increased. Moreover, there were differences in the soil moisture active layer of the six forest lands. Among these forests, the soil moisture active layer was deepest in H. rhamnoides forest (80 cm), and other vegetation types had relatively shallow (20-40 cm) active layers. In the 0-100 em soil layer, the vertical variation trends in soil water storage differed considerably among forest lands. There were significant differences among P. simonii, P. hopeiensis, and H. rhamnoides (P<0.05). The soil water storage of H. rhamnoides in each season increased first and then decreased as soil depth increased. The water storage deficits of different vegetation types were significantly different; the degree of the soil water deficit in different seasons was in the order of autumn>spring summer [ABSTRACT FROM AUTHOR]

This study aims to characterize the soil quality of returning farmland to forest (grass) land in the loess region of northern Shaanxi, particularly on its response to the precipitation. Taking Wuqi county, Shaanxi Province as the research area, three precipitation gradients were divided into 370-395, 440-445, and 460-470 mm. Correspondingly, three typical locations were also selected as Wangwazi (370-395 mm), Dajigou (440-445 mm), and Baibao (460-470 mm). A quantitative evaluation was carried out in three precipitation areas, combining with the soil quality index. The comprehensive scores were achieved, including the soil physical structure, water holding capacity, salinity, carbon sink index, and available nutrient index, for the widespread Robinia pseudoacacia, Hippophae rhamnoides, and grassland. An attempt was made to clarify that the soil quality characteristics changed with precipitation gradients after vegetation restoration. The results showed that: 1) Precipitation, vegetation types, and their interaction had significant effects on soil indicators (P<0.05). 2) In the 460-470 mm precipitation area, Robinia pseudoacacia forest (0.829) had the best effect on soil quality improvement, followed by Hippophae rhamnoides forest (0.808). The soil quality of both reached the fertile level, and the difference was not significant. Grassland (0.679) had the lowest soil quality index, and the soil was at a more fertile level. In the 440～445 mm precipitation area, the Hippophae rhamnoides (0.764) had the best comprehensive soil quality indexes, followed by the Robinia pseudoacacia (0.672), both of which reached a relatively fertile level, whereas, the grassland (0.479) had the lowest soil quality index at a medium level. In the 370-395 mm precipitation area, the comprehensive soil quality index of the three vegetation types from large to small was Hippophae rhamnoides forest (0.792), Robinia pseudoacacia forest (0.433), grassland (0.270). The soil quality grade of Hippophae rhamnoides forest was relatively higher. Robinia pseudoacacia forest and grassland were at the medium and barren level, respectively. 3) Within the precipitation gradient of 370-470 mm, the soil quality index of three planting types all decreased with the decrease of precipitation. Among them, the Hippophae rhamnoides forest (2.34%) had the lowest coefficient of variation of the comprehensive index of soil quality, whereas, the Robinia pseudoacacia forest and grassland had higher coefficient of variation (25.27% and 34.34%, respectively). The findings can provide scientific datum and theoretical support to implement ecological forestry projects, with an emphasis on the vegetation restoration and reconstruction under the precipitation gradient of 370-470 mm in the loess area of northern Shaanxi, China. [ABSTRACT FROM AUTHOR]

Copyright of Bulletin of Botanical Research is the property of Bulletin of Botanical Research Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Research & Exploration in Laboratory is the property of Research & Exploration in Laboratory and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Research & Exploration in Laboratory is the property of Research & Exploration in Laboratory and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Shandong Medical Journal is the property of Shandong Medical Health Newspapers and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Shandong Medical Journal is the property of Shandong Medical Health Newspapers and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A robust adaptive control approach based on cubic Hermite spline interpolation (CHSI) and neural network is proposed for the path tracking of underactuated unmanned surface vehicles (USVs). A smooth nonlinear desired path is obtained by using CHSI method to fit the way-point, which solves the problem of swing and twist of USV caused by traditional linear path. Based on the Serret-Frenet frame, an adaptive line-of-sight (ALOS) guidance law is setablished to improve the rate of convergence and reduce the oscillation. Considering the influence of model uncertainties of USV and environmental distur- bance, a concise robust adaptive neural network controller was developed. The proposed control strategy can effectively improve the accuracy and quality of path tracking control, and has the advantages of less learning parameters and computing load. The convergence of the system is proven through stability analysis, and the effectiveness of the proposed control scheme is verified by using the simulation examples. [ABSTRACT FROM AUTHOR]