Browsing by Author "Almeida, M. T."
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- Chemical control of wall vegetation - neutralisation of herbicidesPublication . Mouga, Teresa; Almeida, M. T.; Rosa, P. J.The chemical control of limestone-growing wall vegetation has to be made carefully, to prevent damage caused by acid herbicides. The results obtained with a new methodology of herbicide neutralisation by potassium hydroxide are here presented. This neutralisation proved its efficiency both in killing the plantsand decreasing the damage caused to the stone.
- Existence of Verbascum levanticum I. K. Ferguson in PortugalPublication . Mouga, Teresa; Almeida, M. T.The species Verbascum levanticum I. K. Ferguson was introduced as an ornamental in the Botanical Garden of Coimbra, in the 19th century. It became naturalized over restricted areas in the centre of Portugal, colonizing walls, rock fissures and dry land. However, during during the past two years, we have found it growing quite vigorously on some walls in Coimbra. The existence of the species is discussed.
- Neutralisation of herbicides. Effects on wall vegetationPublication . Mouga, T. M.; Almeida, M. T.The chemical control of wall vegetation growing on monuments has been stated as a suitable instrument of conservative intervention. However, often the use of herbicides has not been the most suitable, endangering either the environment or the monument in question. In particular, when dealing with limestone monuments, the chemical control has to be made very carefully because all the carbonate rocks are particularly sensitive to the weathering action of acids. Thus. to prevent this damage, two acid herbicides were neutralised with potassium hydroxide. This neutralisation did. in fact, decrease the damage caused by their acidity on the limestone. This paper deals with the effects of these neutralised herbicides on higher plants. Several experiments were made to determine whether the efficiency of the herbicides was affected. Also. the neutralisation did not affect the ability of the herbicides to eliminate the wall vegetation.
- The weathering ability of higher plants. The case of Ailanthus altissima (Miller) SwinglePublication . Almeida, M. T.; Mouga, T.; Barracosa, P.The growth of higher plants in monuments causes wheathering of the substrata and can be one of the biggest problems for conservators.