Rettifica di immagini epipolari

In document Sviluppo e Applicazioni di Tecniche di Automazione in Fotogrammetria dei Vicini (Page 114-120)

2.4. Pre-elaborazione delle immagini

2.4.3. Rettifica di immagini epipolari

(Mutimukuru-Maravanyika and Almekinders, 2010; Mutimukuru-Maravanyika 2010). But despite the lessons learned during this project, the Forestry Act remains the same.

The Forestry Commission is currently engaged in the National Forest Programme, funded by the FAO, to develop a new forest policy. The National Forest Programme is currently undertaking a review process to ensure that there are synergies between new forestry policies and practice on the ground. The Programme will also help Zimbabwe’s forestry sector to integrate sustainable forest management into poverty reduction strategies, and build consensus on how to address forestry issues at the national level. This process provides a unique and timely opportunity for climate change issues to be addressed in forestry policy.

(1) (a), a Catchment Council may limit the quantity of water abstracted for primary purposes to ensure equitable distribution and use of water.

The Act also states that whenever the volume of water in any river system is insufficient to satisfy demand, the Catchment Council may revise, reallocate or reapportion permits and put in place conditions that ensure equitable distribution and use of the available water. This provision is critical during periods of drought. The power vested in the Catchment Councils is important as a policy decision and as an adaptation strategy, as it ensures that all people cope and manage to access water during periods of shortage.

Further, there are several other climate change-related adaptation measures implicit in the Water Act, which may be invoked to enable people to cope with droughts, floods and other emergencies caused by climate change. For example, Section 57 of the Act gives the Minister of Water Resources the power to issue a notice to reserve any specified quantity of water for future use, as well as the power to declare any area as a water restriction area, if water use is approaching the potential limit of the catchment.

Section 61 (1) of the Act states that if the flow of water in any public stream or water storage works has ceased, or the levels have fallen or are likely to fall, the Minister may declare the area to be a water shortage area, on the recommendation of ZINWA and in consultation with the relevant Catchment Council. If an area has been declared a water shortage area, the Catchment Council may:

suspend or amend any water use permits; make orders on abstraction, appropriation, control or use of the water; and determine the priority for water use in the area. The Catchment Council may also restrict the sinking of boreholes or wells or fix the maximum volume of water which may be abstracted from any public stream, water storage work, borehole or well in a water shortage area, under the terms of Sections 63 and 64. These provisions provide a legal framework for coping with water shortages during drought periods.

Sections 99–102 of the Water Act make provisions for the safety of dams. They prescribe some of the safety requirements for the construction of both small and large dams, in terms of design, plans and specifications. The Act prescribes that the adequacy and safety of every dam has to be certified by an approved civil engineer and dams must be periodically inspected. The law recognises the need to ensure that dams are strong enough to withstand floods. Dam safety measures and procedures are critical in the event of floods, and may reduce the destruction of property, homes and livestock of communities living downstream. This is a climate change adaptation measure.

Section 109 (1) of the Water Act specifically relates to floods. Sub-section (1) states that if the owner of a dam learns of a flood that may affect the dam, s/he shall take all reasonable and practical steps to deal with the flood. In addition, the owner of the dam is required to notify the Secretary in the Ministry of Water Resources and ZINWA of the flood. The law makes it an offence to not take reasonable or practical steps or to notify the Ministry. Although The Water Act it does not explicitly link the floods to climate change, these provisions may be sufficient for dam owners to respond to climate change related floods.

The Zimbabwe National Water Authority Act established ZINWA, which is mandated to carry out several functions that have implications for climate change adaptation in Zimbabwe. One of the Authority’s critical functions is to advise the Ministry of Water Resources on the formulation of policies and standards on: water resources planning, management and development; hydrology;

dam safety; and the protection and conservation of water resources. These functions encompass climate change adaptation issues, such as the monitoring of rainfall, the safety of dams against floods, and the need to conserve water when there are shortages. In addition, ZINWA is mandated to: undertake research studies; develop a database on hydrological issues and publish the findings;

and produce maps, plans and other information necessary for development and exploitation of water resources. These activities will help to understand how climate change affects water resources management.

More importantly, ZINWA has the responsibility of advising the Ministry of Water Resources on the exploitation, conservation and management of water resources of Zimbabwe, with the objective of taking appropriate measures to minimize the impact of drought, floods or other hazards. This function places the Authority at the centre of ensuring that people are not greatly affected by droughts and floods. Given this legal position, it is incumbent upon the Authority to ensure that the Ministry of Water Resources is appropriately advised to adopt measures to adapt and cope with climate change.

ZINWA can promote climate change adaptation, and has the power to construct, establish, acquire, maintain or operate dams, reservoirs, canals, water distribution works and hydropower stations in any area. These powers are provided in the Schedule to Section 6 of the Act and place the Authority at the core of ensuring water availability even during times of shortage.

The Water Act establishes Catchment Councils and Sub-catchment Councils, which have responsibility for managing river systems. The key functions of these Councils include: preparation

and updating outline plans for river systems; deciding and enforcing water allocations and reallocation; working with ZINWA to maintain a database and information system for the catchment; determining applications for the use of water and imposing the conditions that are necessary; monitoring the activities of Sub-catchment councils (by Catchment Councils); and maintaining all registers of permits issued for access by members of the public. Under Section 12 (1), Catchment Councils have the following powers: to grant or refuse applications for a provisional permit or temporary permit for use of water; to carry out inspections; to revise or cancel permits; to grant permits for the construction of water storage works; to ensure compliance with the Water Act.

The functions of Catchment and Sub-catchment Councils provide an institutional framework for adaptation to climate change in the water sector.

Despite the fact that the legislation governing water has important climate change implications, it makes no explicit reference to climate change. Further, the implementation and enforcement of various pieces of legislation is often hindered by political, economic and social factors. These include shortages of funds, fuel, transport and equipment, and government interference in the operations of public bodies and local authorities. Communities also lack knowledge of these laws and how to claim their rights, which also stifle implementation and enforcement of these laws.

In document Sviluppo e Applicazioni di Tecniche di Automazione in Fotogrammetria dei Vicini (Page 114-120)