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621.
Street trees are important foundations of urban sustainability due to the ecosystem services that they provide society and the environment. However, street trees are vulnerable to vandalism and damage, especially when small, which constraints the flow of benefits they provide and also increases the costs of planting programmes. Despite being a common phenomenon, there is limited knowledge regarding the extent of vandalism and the reasons for it. Here we seek to understand the causes and extent of street tree damage in eleven small Eastern Cape (South Africa) towns and to assess the perceptions of residents and officials. The condition of newly planted street trees was assessed in each town and residents were interviewed in the two towns with the highest number of newly planted street trees. Almost half (42%) of recently planted street trees were totally snapped, ranging between 0% and 63% per town. There was no difference in the prevalence of trees being snapped between those with protective structures and those without. Each town used different structures around newly planted street trees, but in only two towns were all the structures intact. The prevalence of damage declined with increasing trunk thickness and increasing town size. According to residents, boredom, misbehaviour, lack of appreciation of trees and collection for wood were the main factors for tree vandalism by people along with damage by livestock. Ward councillors recognised the presence of vandalism, but indicated that it was not a priority topic in their ward meetings. Suggestions by residents to prevent vandalism included: planting in sensible areas, re-designing the protective structures, re-locating livestock and engendering community participation and ownership in all aspects of street tree planting. 相似文献
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R. J. Summerfield K. E. Cockshull D. Dickinson A. C. Richardson 《The Journal of Horticultural Science and Biotechnology》2013,88(2):161-166
To meet the diverse requirements of growing a range of plants to all stages of growth in controlled environment cabinets, versatile systems of quantitative irrigation have been developed. The two systems described are easily intercon- verted, occupy a minimum of plant-growing space and can easily be modified to suit particular requirements. The systems are constructed from readily available materials and enable the volume, time, duration and frequency of the irrigating solution to be precisely controlled. 相似文献
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The restoration potential of the Mesopotamian marshes of Iraq 总被引:1,自引:0,他引:1
Richardson CJ Reiss P Hussain NA Alwash AJ Pool DJ 《Science (New York, N.Y.)》2005,307(5713):1307-1311
Uncontrolled releases of Tigris and Euphrates River waters after the 2003 war have partially restored some former marsh areas in southern Iraq, but restoration is failing in others because of high soil and water salinities. Nearly 20% of the original 15,000-square-kilometer marsh area was reflooded by March 2004, but the extent of marsh restoration is unknown. High-quality water, nonsaline soils, and the densest native vegetation were found in the only remaining natural marsh, the Al-Hawizeh, located on the Iranian border. Although substantially reduced in area and under current threat of an Iranian dike, it has the potential to be a native repopulation center for the region. Rapid reestablishment, high productivity, and reproduction of native flora and fauna in reflooded former marsh areas indicate a high probability for successful restoration, provided the restored wetlands are hydraulically designed to allow sufficient flow of noncontaminated water and flushing of salts through the ecosystem. 相似文献
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