Search

Copyright of Food & Fermentation Industries is the property of Food & Fermentation Industries 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.)

[Objective] Exploring the temporal and spatial changes of Potential Natural Vegetation (PNV) and identifying the intervention intensity of human activity on PNV in the Hekouzhen-Longmen Region of the middle reaches of the Yellow River can provide a theoretical reference for regional ecosystem restoration, reconstruction and sustainable development. [Methods] Based on meteorological data from 1960 to 2017 and land use data from 1990 to 2018 in the Hekouzhen-Longmen Region, we used GIS technology and Comprehensive and Sequential Classification System (CSCS) model to simulate and analyze the temporal and spatial variation characteristics of PNV in the Hekouzhen-Longmen Region from 1960 to 2017, and explored the intervention intensity of human activity on PNV since 1990. [Results] The stable PNV types in the Hekouzhen-Longmen Region were sorted in descending order of area as follows: Warm temperate-semiarid warm temperate typical steppe, Warm temperate-subhumid forest steppe, Cool temperate-subhumid meadow steppe, Cool temperate-semiarid temperate typical steppe. Different degrees of centroids of PNV types had shifted in different ages. The center of gravity of PNV types had migrated in different degrees in different ages. The land use types were mainly grassland, cultivated land and forestland. The areas of grassland, forestland and construction land showed an increasing trend, while the areas of cultivated land and other land types showed a decreasing trend. The center of gravity of each land use type was also changing. Affected by human activity, 30.9%～36.2% and 11.4%～18.5% of steppe PNV were transformed into cultivated land and forest land respectively, and 19.0%～32.6% of forest-steppe PNV was transformed into cultivated land. The proportion of potential grassland area converted to forestland was increasing year by year, [Conclusion] The dynamic change degree of human activity′ interference to PNV was larger in 1990—2000 and 2010—2018, especially in 2010—2018, and more attention should be paid to whether the existing forestland can survive continuously. [ABSTRACT FROM AUTHOR]

Copyright of Piezoelectrics & Acoustooptics is the property of Piezoelectric & Acoustooptic 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 Bulletin of Soil & Water Conservation is the property of Bulletin of Soil & Water Conservation 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 Engineering Management & Technology Discussion is the property of Omniscient Pte. Ltd. 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.)