botanical specialist report january 2013 ranobe mine rpt english cb0503… · aristida sp. indet....

Botanical Specialist Report – January 2013

Coastal & Environmental Services Ranobe Mine Project 27

Plate 4-2: A: Limestone forest/thicket on steep limestone slopes. B. Dense shrub cover emerging from slabs of limestone, and C: Dry season indictating areas of limestone slopes cleared for the cultivation of maize.



Plate 4-3: A: Limestone forest and B: Degraded Limestone forest

Plate 4-4: A. Adansonia za – Delonix bolviniana Forest community with Adansonia za and Euphorbia tirucalli shrub in foreground. B. Characteristic elongated fruit of Adansonia za.



The following were present in at least 3 of the 5 plots:

Trees or large shrubs

Adansonia za Allophylus dissectus Cedrelopsis grevei Chadsia grevei Colvillea racemosa Commiphora aprevalii Commiphora simplicifolia Delonix boiviniana Delonix floribunda Entada chrysostachys

Euphorbia tirucalli Gardenia decaryi Givotia madagascariensis Hypoestes poissonii Mimosa grandidieri Mundulea micrantha Phyllanthus casticum Stereospermum variabile Strychnos madagascariensis

Herbs and small shrubs

Acalypha decaryana Camarotea souiensis Henonia scoparia

Lasiocladus anthospermifolius Oplonia minor Sida acuta

Climbers

Aristolochia albida Meiostemon humbertii Paederia grandidieri

Peponium poissonii

Present throughout were:

Cedrelopsis grevei Commiphora aprevalii

Limited to this community were:

Henonia scoparia Sida acuta

Delonix boiviniana Hypoestes poissonii

4.2.4 Community D: Spiny Thicket This community is found on the coastal plain between the Ranobe Exploration Area and the coast, and 157 species were recorded in the plots sampled. In the project area it forms the dominant type of vegetation, and is very species rich. Along the western edge of the project area a broad transition zone exists between the Adansonia rubrostipa thicket and the Adansonia za (Community C) forest. There is clearly a transition within the thicket from the east to the west, and from the north to the south that was reflected in our analysis. Rejo-Fienana (1995) separated a community characterized by Didierea madagascariensis, Givotia madagascariensis, and Adansonia rubrostipa (Plate 4-5) further inland from one characterised by Didierea madagascariensis (Plate 4-6), Cedrelopsis greveana and Euphorbia stenoclada nearer to the coast. To the south the density of Didierea madagascariensis increases relative to other tall species, primarily the result of selective exploitation of the more useful species. Common species of the spiny thicket are shown in Plate 4-7 below. The Adansonia rubrostipa thicket described here is very restricted in extent, and although the characteristic baobab species extend in a narrow coastal belt southwards to near Itampolo and north to near Mahajanga, many of the other species present have a very restricted range. It appears to be limited by the Fiherenanana River in the south, but extends along the coastal plain north of the Manombo River into the southern part of the Mikea Forest. Further to the north the vegetation changes gradually, and some of the species characteristics of the thicket in the project area are replaced by others. The spiny thicket of the area is extensively degraded and there is very little intact thicket remaining at all. Even the areas mapped as Spiny thicket are extensively degraded with few hardwood trees remaining. In addition, two other levels of degradation are apparent. Degraded Spiny thicket shows the removal of much of the vegetation, with primarily Didiera madagascariensis remaining. Very Degraded Spiny thicket is almost completely denuded of vegetation due to wood harvesting and fire. These areas are largely bare soil with some scattered thicket species. Plate 4-8 indicates these three levels of degradation within the Spiny thicket community.



The following were present in at least 5 of the 9 plots:


Adansonia rubrostipa Allophylus dissectus Boscia madagascariensis Capurodendron greveanum Cedrelopsis grevei Chadsia grevei Clerodendrum globosum Commiphora aprevalii

Commiphora falcata Commiphora laxecymigera Commiphora orbicularis Commiphora simplicifolia Delonix floribunda Didierea madagascariensis Entada chrysostachys


Karomia glabrescens

Climbers

Cissus bosseri Combretum grandidieri

Helinus brevipes

The following were present in all or all but 1 plot:

Chadsia grevei Commiphora orbicularis Commiphora simplicifolia

Entada chrysostachys Gardenia decaryi

The following were present in no more than 3 other plots:

Adansonia rubrostipa Capurodendron greveanum

Cissus bosseri Commiphora falcata



Plate 4-5: Adansonia rubrostipa, the common baobab of the Adansonia rubrostipa spiny thicket community. A: The trees in a small patch; B: Buds and flowers; C: Old fruits on the ground amongst other detritus.



Plate 4-6: Didierea madgascariensis, a dominant species of the Adansonia rubrostipa spiny thicket.



Plate 4-7: A: Aloe divaricata, a common succulent found in open spaces within the spiny thicket, B: Flowers of the climber, Combretum grandidieri, and C: Flowers of Fernandoa madagascariensis in the Adansonia rubrostipa spiny thicket community.



Plate 4-8: The Spiny Thicket has been further divided into three types, with different levels of degradation. A: Spiny Thicket, B: Degraded Spiny Thicket and C: Very Degraded Spiny Thicket.



4.2.5 Community E: Tamarindus Bushclumps This community is found throughout the Ranobe Exploration Area at sites where more extensive forest patches are absent. It consists of patches of woody vegetation of varying sizes associated with open areas that are largely denuded of woody plants (Community F). In some cases the Bushclumps consist of a single large tree, often Tamarindus indica, with an associated community of smaller trees or shrubs, climbers and herbs in its shade that differ substantially from those found in the surrounding open areas. In these communities we recorded 28 species in the plots sampled (Sclerocarya birrea was seen in many bushclumps, but was not actually found in any of the plots sampled). The bushclumps and the associated open areas form a mosaic that we interpret as secondary vegetation that has resulted from human impact, and is maintained as sub-climax by grazing and burning (Plate 4-9). It is not certain what the original vegetation of these areas would have been. However, we believe that it does not represent a form of degraded Adansonia za forest as might be supposed, but that it represents the remnants of gallery forest. This forest type occurs on deep sand along rivers or underground watercourses throughout south-west Madagascar, but has largely been destroyed or degraded. The species compliment of the bushclumps provides supportive evidence for this hypothesis.

Species common to most plots:


Albizia aurisparsa Catunaregam spinosa Commiphora aprevalii Commiphora simplicifolia Didierea madagascariensis Diospyros sakalavarum Entada chrysostachys Euclinia suavissima Fernandoa madagascariensis Flacourtia amontchi

Grewia calvata Grewia franciscana Grewia lavanalensis Ixora malacophylla Neobeguea mahafaliensis Phyllarthron bernierianum Sclerocarya birrea subsp caffra Tamarindus indica Tetrapterocarpon geayi Zanthoxylum decaryi

Climbers

Abrus precatorius Gouania callmanderi Helinus brevipes Paederia grandidieri Secamonopsis madagascariensis

Paederia grevei Pentopetia androsaemifolia Pentopetia ovalifolia Peponium poissonii

The following were present in all plots:

Commiphora aprevalii Euclinia suavissima Flacourtia indica Fernandoa madagascariensis

Grewia calvata Grewia lavanalensis Paederia grandidieri Tamarindus indica

The following were not present elsewhere or in one other plot:

Abrus precatorius Catunaregam spinosa

Diospyros sakalavarum Flacourtia amontchi



Plate 4-9: A: Disturbed area with Tamarindus indica Bushclumps in open herbaceous communities of B: Tephrosia purpurea. 4.2.6 Community F: Open areas between bushclumps This community is found throughout the Project Area where the woody vegetation has been destroyed, and a community dominated by grasses and other herbs has become established. However species richness is low, with only 30 species being recorded in our study. Many of the plants are annuals or short-lived perennials, and at dry times bare ground and dead stems are all that can be seen. However, at the time of our work, the legume Tephrosia purpurea subsp leptostachya was dominant at most sites (although it was absent from one). The open areas are presumed to be maintained largely by grazing and trampling by domestic stock, whether fire plays a significant role is unknown. Signs of regeneration of woody vegetation are visible with saplings of some of the tree species typical of bushclumps or forest being present, among which Chadsia grevei and Entada chrysostachys were the most common. In some areas climbers such as Combretum albiflorum or Microsteira ampihamensis form dense tangled mounds which may be important as nurse sites for the establishment of tree seedlings and as refuges for animals.



30 species were recorded in this community as follows:

Grasses and sedges:

Acroceras boivinii Aristida sp. indet. Bulbostylis sp. indet Cenchrus ciliaris Dactyloctenium ctenoides

Digitaria sp. indet Hyperthelia dissoluta Panicum maximum Panicum sp. indet


Abutilon pseudocleistogamum Acanthospermum hispidum Achyranthes aspera Aerva javanica Bidens bipinnata Boerhavia diffusa Cleome grandidieri Commelina ramulosa Euphorbia hirta

Indigofera tinctoria Perotis patens Rapona tiliifolia Rhinacanthus nasutus Sida cordifolia Tephrosia purpurea Tridax procumbens Vernonia neoperrieriana Waltheria indica

Woody plants:

Chadsia grevei Entada chrysostachys

Succulent

Aloe divaricata

The following were present in 3 or more of plots:

Dactyloctenium ctenoides Panicum maximum

Sida cordifolia Tephrosia purpurea

Found in 5 of the 6 plots:

Tephrosia purpurea

Widespread in other plots

Chadsia grevei Entada chrysostachys

4.2.7 Community G: Intermediate Forest This community type is found on the Western edge of the Project Area. Although it cannot be statistically differentiated from the spiny thicket or the dry forest, it does form an ecotone between the two. This vegetation type includes elements of both the dry forest and spiny thicket and it forms an important transition zone. There is species overlap between those recorded in both the dry forest and spiny thicket. All these areas are degraded and two different levels of degradation have been recorded: Intermediate Forest and Degraded Intermediate Forest, but it is clear that all of this vegetation type is degraded (Plate 4-10).

Plate 4-10: A: Intermediate forest/Thicket and B: Degraded Intermediate Forest/Thicket



4.2.8 Comparison of vegetation communities The vegetation communities we report are related to those of previous studies in the area as summarised in Table 4-1 below. Table 4-1: The vegetation communities recognised in the present and previous studies

2012 2007 Phillipson et al., (2003).

Woods (2003) Rejo-Fienana (1995)

Community A: Colvillea-Tamarindus forest patches


Not studied Limestone Thicket/Dry Dense Forest transition

Not studied

Community B: Limestone forest

Community B: Limestone forest/thicket

(iv) Thicket on limestone

Limestone Thicket

Not studied

Community C: Dry Forest

Community C: Adansonia za - Delonix boiviniana forest

(iii) Baobab (Adansonia za) forest

Dry Dense Forest Zone 3 (in part)

Community D1: Spiny Thicket

Community D1: Adansonia rubrostipa thicket

(i) Thicket on unconsolidated sand ii) Secondary thicket on unconsolidated sand

High Thicket Zones 1 and 2

Community E: Tamarindus Bushclumps

Community E: Tamarindus Bushclumps

(v) Wooded grassland (part of)

Savanna (part of) Zone 4

Community F: Open areas

Community F: Open areas

(v) Wooded grassland (part of)

Savanna (part of) Not studied

Community G: Intermediate Forest

Community D2: Adansonia rubrostipa intermediate thicket/forest

Not studied Not studied Not studied

The vegetation in the entire project area (between the Fiherenana and Manombo Rivers) is of considerable importance in terms of its beta diversity (the communities of plants that it contains) and its alpha diversity (the species present). Most important in this regard is the thicket vegetation on the sandy coastal plain with Adansonia rubrostipa often dominating (Community D), and the thicket and forest at the edge of the limestone plateau (Community B). Both of these vegetation types are exceptionally rich in species, a high proportion of which are very localized in distribution. In the project area as a whole, much of this vegetation was more-or-less intact in 2007, but in 2012 no intact areas remain. The area is under severe human pressure, particularly from charcoal production. The other communities that we recognise are of more limited extent. 4.3 Vegetation mapping Our interpretation of the satellite image with respect to our vegetation classification is given in Figure 4-4. 4.3.1 Vegetation of the Ranobe Exploration Area The predominant vegetation in the Ranobe Exploration Area is a mosaic of Tamarindus Bushclumps (Community E) and open areas (Community F). This vegetation type is common throughout south-west Madagascar, and being a secondary vegetation type it has a low alpha diversity. It is dominant in the lower lying valley between the Limestone Plateau to the east and the red dunes to the west.



The Limestone thicket and forest (Community B) occurs along the eastern edge of the Ranobe Exploration Area, and extends east across the Limestone Plateau. This community is restricted to the limestone substrate. It is also largely cleared within the Ranobe Exploration Area, where maize is grown on the limestone slopes. Small, isolated patches of Colvillea-Tamarindus forest (Community A) are found within the more extensive Adansonia za - Delonix boiviniana forest (Community C), both of which occur along the eastern boundary of the Ranobe Exploration Area, adjacent to or within small valleys that intrude into the Limestone Plateau. These two communities share some species with Community B, but have a species composition that is sufficiently distinct to have been clearly separated by TWINSPAN from Community B. Within the Ranobe Exploration Area many of the areas covered by Communities A and C are degraded, and as a result, the alpha diversity of these communities is much lower than that of the more widespread Communities B and D. The coastal Adansonia rubrostipa thicket (Community D) is found to the west of the Ranobe Exploration Area, and extends westwards towards the sea, where it dominates on red, sandy soils. Closer to the coast species composition changes in response to edaphic and other factors. Within the Ranobe Exploration Area a forest that is transitional between the coastal Adansonia rubrostipa thicket (Community D) and the Adansonia za - Delonix boiviniana forest (Community C) occurs along the south-western edge of the Ranobe Exploration Area (Community G). These plant communities have a very high alpha diversity, with Community G representing an ecotone between Communities D and C. Thus, the species rich and widespread Adansonia rubrostipa thicket that characterises the so-called PK32 area does not occur within the Ranobe Exploration Area. The existence of forested areas (even though these have become degraded since 2007) (Community C) that traverse the Ranobe Exploration Area in two places is particularly important. These forested areas provide an ecological corridor between the limestone vegetation (Community B) and the spiny vegetation communities (mainly Communities C & D) that dominate the sandy areas. They allow for a transition of vegetation ranging from the thicket of the limestone escarpment (Community B) in the east, traversing the forested areas (Communities A & C) to the thicket of the coastal plain to the west (i.e. a series from Communities B to A to C to D). These linking corridors of thicket and forest are an important refuge of plant communities and plant and animal species, which are characteristic of this unique transitional zone. They also provide a potential migration route for plant and animal species between the different ecological areas and this is important in terms of ecosystem function. It is clear that similar forests do not occur to the north within the project area, but the extent to which similar forests may occur along the ecotone of the limestone plateau and the coastal plain to the south is unknown. Satellite imagery suggests that vegetation in similar positions to the south is more open and probably much more degraded, but this has not been confirmed on the ground. 4.3.2 Vegetation from the Ranobe Exploration Area to Toliara The vegetation occurring from the southern edge of the Ranobe Exploration Area to the city of Toliara shows distinctive vegetation types. On the limestone Community B (the limestone forest) is found. Much of this is relatively intact midway between the Ranobe Exploration Area and the city (including the adjacent spiny thicket, Community D), due to an interesting rural legend and it is known that people will not go into these areas to collect wood for charcoal. It is likely that this will not remain intact for long considering the rapid rate of degradation in the the area. Already large tracts of the Limestone Forests have been cleared for wood for charcoal and building, as well as for maize fields. To the West of the Limestone Forest Community D, the Spiny Thicket, which is the most dominant vegetation type of the region is found. This has also been extensively degraded and although the whole area could not be covered, it is clear that there are very few patches of relatively intact vegetation. As mentioned above, there are some areas that people will not clear and these areas remain in good condition. River flood plains are extensively farmed and the forest cleared for fields as well as for charcoal.



A relatively small area of Community G, Intermediate Forest occurs to the west of the Ranobe Exploration Area and extends some way south of the Ranobe Exploration Area. This vegetation type is also extensively degraded and no intact areas were found to exist in the 2012 study. Any isolated patches of less degraded vegetation form an integral part of the ecosystem providing corridors and important ecosystem services. Even areas that are degraded or very degraded should not be underestimated in terms of the biodiversity and ecosystem services they provide. In addition to the vegetation types described above, several other units have been mapped that are not necessarily relevant to an assessment of impacts from the mine and haul roads. These include: Beach, Erosion, Mangrove Swamps, Plantation, Settlement: Houses and associated fields, Settlement: Fields, Settlement: River fields, Wetlands: pan and Wetlands: River (Plate 4-11). Of these, only the mangrove swamps form a vegetation type. These are mostly very degraded areas but still serve an essential role in ecosystem functioning.



Plate 4-11: Units mapped in the vegetation map not forming specific vegetation communities. A: Beach, B: Mangrove swamps, C: Settlement: Houses and Associated Fields, D: Settlement: Fields, E: Settlement: River fields and F: Wetland: River.



Figure 4-4: Vegetation map of Project Area showing the vegetation communities within the Ranobe Exploration Area and mining license area.



4.3.3 Degradation and Human Impacts Within the Ranobe Exploration Area and the wider project area, the effect of human impacts on the vegetation is apparent. These include both long term and short term impacts. Long term impacts have resulted in the development of relatively stable secondary vegetation, notably the Tamarindus Bushclump mosaic. The existence and boundaries of this vegetation in what is now the Ranobe Exploration Area is visible on old maps (e.g. the FTM map based on 1964 aerial photographs), suggesting that this vegetation has changed little over the past four decades. It is believed (but we do not have proof), that the original Toliara to Morombe road passed through this area before the coastal road was constructed, and, if this is true, the conversion of the original vegetation may have taken place along this old communication route. The bushclump mosaic may be important as habitats for wild animals and for grazing of domesticated livestock, and also contain certain plant species that are not found elsewhere in the project area. Short term impacts, notably the complete destruction of the vegetation by fire, may eventually result in the establishment of stable secondary vegetation, but if areas are used for crop production then the natural vegetation is largely destroyed. In general, the areas that have been destroyed recently are those that naturally support a different vegetation type to those traditionally used for pastoral and arable practices. Therefore, little is known about natural regeneration of vegetation cover in these areas, nor about the ability of the local human population to convert degraded areas into stable and productive agricultural land. It is interesting to note that the vegetation in the northern half of the Ranobe Exploration Area is more degraded than the southern portion, which is further away from the villages, which are generally closer to the river and the more fertile, alluvial soils that can be irrigated. The northern half is dominated by the Bushclumps and open grasslands, indicating that the natural vegetation has been transformed through significant loss of woody species and loss of biodiversity. By contrast, in the southern half of the Ranobe Exploration Area the vegetation tends to be somewhat more intact although still degraded. Throughout the Project area, the herbaceous legume Tephrosia purpurea subsp leptostachya is one of the most important primary colonisers of open areas, and certain shrubs (notably Combretum albiflorum and Microsteira ampihamensis) play an important role as nurse sites for the establishment of seedlings of certain pioneer tree species. Thus, if natural successionary processes are allowed to proceed, bushclumps may start to form in the open areas around clusters of pioneer tree species and around individual trees or small patches of forest that have escaped destruction. In this way, a mosaic of bushclumps and open areas will form. With moderate regular human disturbance, i.e. grazing, trampling and burning of the open areas, such areas may persist and become relatively stable, like the mosaic of Communities E and F that predominate in the Ranobe Exploration Area, but eventually the bushclumps may coalesce to form a more-or-less continuous forest or thicket in the absence of disturbance. Human impacts have resulted in the loss of large numbers of both hard and softwood trees throughtout the entire project area (in addition to the Ranobe Exploration Area, discussed above). This degradation is occurring at an extremely rapid pace. The original study done in 2007 indicated the presence of areas of intact vegetation both within and surrounding the Ranobe Exploration Area, in 2012, this is no longer the case. The majority of the vegetation is degraded with very few isolated patches of relatively intact vegetation. An indication of the rapidity of the degradation can be seen in Figure 4-5 below. This imagery shows intact vegetation in green, and degraded or cleared vegetation in orange. The first image shows the area in 2006, and the second in 2012. Over a period of 6 years 18 400 ha of vegetation has been cleared (Figure 4-5). In 2006, 18% of the PK32 area had been cleared compared to 2012 where 31% of the area had been cleared. It is clear that an incredible amount of degradation has occured during this time period.



Figure 4-5: Satellite images showing the spread of cleared areas over a 6 year period from A: 2006 to B: 2012. Plate 4-6 indicates the major causes of degradation in the area. The areas of natural vegetation remaining are criss-crossed with tracks for the zebu that are used to pull carts for collecting from the forest areas. This has opened up all of the vegetation of the area, and tracks allow for access to vast areas of vegetation. Some areas are almost completely cleared and these can be seen on satellite imagery. Many of the large trees are used to make boats (see the Resource Use report for details), and the chopping down of these large trees creates open areas. The most destructive of all of the pressures on the vegetation is the production of charcoal. As there are few or no hardwoods left for making charcoal, softwoods, shrubs and even Didieria madagascariensis are now used for charcoal production. In some areas the result of this is completely bare ground with some scraggling herbs and climbers. Poles are also harvested for building, resulting in the loss of saplings. Another huge impact on the vegetation is the setting of fires. Local people will set fires in order to encourage the growth of grass for the grazing of domestic cattle. Although this does encourage grass growth, fire kills any seedlings, and also kills much larger plants. If frequently burned, the indigenous vegetation cannot recover and the result is large open areas that are completely bare in the dry season. This has potential secondary impacts such as erosion and the loss of topsoil.



Plate 4-6: Major impacts on the vegetation throughout the project area. A: Aerial imagery of zebu tracks crisscrossing the vegetation of the project area, B: Zebu tracks through Intermediate thicket, C: The remnants of a tree after a boat has been made, D: A local boat, E: most f the trees and shrubs are felled for the making of charcoal, F: Poles are cut for building and G: Areas are burned to create grazing for zebu cattle.



5. SENSITIVITY Considering the levels of endemicity in Madagascar as a whole, and the potential global importance of the biodiversity of the project area, it is necessary to draw on a number of different norms and standards regarding sensitivity and conservation importance. The sensitivity analysis aims to determine, using both published data as well as data from baseline studies of the site itself, the ecological sensitivity of the entire project site. The ecological sensitivity is independent of project activities and indicates which areas that have high, medium and low sensitivity to environmental perturbations and development, with development ideally restricted to the low sensitivity areas. This identification of ecologically sensitive areas provides a tool for determining where development should take place, and where ecological corridors, or conservation areas should be placed. 5.1 IFC Standards: Performance Standard 6 This standard addresses biodiversity and has criteria for the determination of areas earmarked for development as Critical Habitat. Two questions need to be answered in order to determine this, and are applied only to Endangered or Critically Endangered Species:

1. Which areas will be impacted? 2. Where else in the world or Madagascar do the species in the specific areas live?

The management areas in which these occur must either:

1. Sustain >= 10% of the global population of the species or; 2. Be one of 10 or fewer sites globally that sustain the species

Considering the high levels of endemicity in Madagascar, the already degraded nature of the study site, and the threat of the current rate of degradation leading to the loss of habitat, it can be clearly stated that the study site as a whole must be defined as a Critical Habitat as defined by IFC Performance Standard 6. 5.2 High Conservation Value Forests A “Toolkit for Identifying High Conservation Value (HCV) Forest” has been developed by Proforest (Jennings et al. 2003). The HCV system is based on the properties of forests, whether these properties (or values) relate to wildlife habitat, watershed protection, resource use, archaeology or other uses/values. In some cases these values are of outstanding significance or are of critical importance, and in these cases the forest can be considered of High Conservation Value (an HCV forest sensu Jennings et al. 2003). Six different HCV categories have been defined and are presented in Table 5-1 below (taken from Jennings et al. (2003). The work done at Ranobe for the ESIA, from identification of species of special concern to the sensitivity analysis provides sufficient data to determine whether or not any areas of the site fall into any of the HCV categories. It must be noted that this is a tentative and preliminary HCV assessment and the field data gathered is certainly not enough to clearly define actual HCV status. The vegetation types described in Chapter 4, above, were each assigned an HCV value, resulting in a preliminary HCV map for the study site (Figure 5-1). Table 5-2 below indicates the process in assigning each vegetation type to an HCV category.



Table 5-1: The six HCV Categories (taken from Jennings et al. (2003). HCV Description

HCV 1 Forest areas containing globally, regionally or nationally significant concentrations of biodiversity values (e.g. endemism, endangered species, refugia).

HCV 2 Forest areas containing globally, regionally or nationally significant large landscape level forests, contained within, or containing the management unit, where viable populations of most if not all naturally occurring species exist in natural patterns of distribution and abundance.

HCV 3 Forest areas that are in or contain rare, threatened or endangered ecosystems.

HCV 4 Forest areas that provide basic services of nature in critical situations (e.g. watershed protection, erosion control).

HCV 5 Forest areas fundamental to meeting basic needs of local communities (e.g. subsistence, health).

HCV 6 Forest areas critical to local communities‟ traditional cultural identity (areas of cultural, ecological, economic or religious significance identified in cooperation with local communities).

Table 5-2: HCV values for each vegetation type Vegetation type Salient features HCV Status

For all vegetation types Within the Madagascar and Indian Ocean Islands Biodiversity Hotspot

Within the WWF Madagascar Spiny Thicket Ecoregion


Isolated areas of forest

Important for use for the communityof the area HCV 5

Community B: Limestone forest

Presence of species of special concern

Globally important levels of endemism

Habitat for animal species

Important resource for the community

Areas determined as Very Degraded have been assigned an HCV category of 5

HCV 1

Community C: Dry Forest Presence of species of special concern



Restricted range

Important resource for the community


HCV 1

Community D: Spiny Thicket Presence of species of special concern



Restricted range

Important resource for the community (essential)


HCV 1

Community E: Tamarindus bushclumps and Community F: Open areas between bushclumps

These areas are essential for grazing, and for collection of timber and non-timber forest products.

HCV 5

Community G: Intermediate Forest

Presence of species of special concern



Restricted range

Important resource for the community (essential)


HCV 1



Figure 5-1: Tentative High Conservation Value Forest map of the project area and surrounds, indicating the majority of the area forming an HCV 1. The Ranobe Exploration Area is outlined in black and the mining license area’s in blue and orange.



5.3 Sensitivity The sensitivity map was developed by identifying areas of high, medium and low sensitivity (Figure 5-2). Areas of high sensitivity include process areas such as rivers, wetlands and streams that are important for ecosystem functioning, including surface and ground water as well as animal and plant dispersal. High sensitivity is also usually given to areas that have high species richness and are not significantly impacted by current land use and hence are not degraded. They also contain the majority of species of special concern found in the area and may contain high numbers of globally important species, or comprise part of a globally important vegetation type. Medium sensitivity is given to areas that, despite being somewhat degraded, still provide a valuable contribution to biodiversity and ecosystem functioning as they are not very degraded and have a relatively high species richness. These areas may also contain species of special concern. Low sensitivity is given to areas that are highly impacted by current land use and thus highly degraded and provide no value to the ecosystem and are highly unlikely to harbour any species of special concern. In the case of the project area, much of the area is rated as having a high ecological sensitivity. This is due to the overall high levels of endemism of the area, and the contribution that this vegetation provides to the biodiversity of the region despite its current state of degradation. It is important to note that continued land use by the local communities is expected to completely eradicate the natural vegetation of the region in a relatively short time. This would result in the ecological sensitivity of the entire area being reduced to low, with irreparable loss of globally important biodiversity, endemicity and ecosystems. Areas of natural vegetation that are more degraded have been assigned a medium ecological sensitivity due to the loss of species due to local pressures on the environment. Low sensitivity areas are those that do not support indigenous vegetation at all (fields and cleared areas). Ideally, development should be restricted to those areas that have a low ecological sensitivity, and exclude those areas with a high or medium ecological sensitivity. Although the WWF has assigned much of the area to a protected area named PK32, this area is not managed for conservation in any way and is rapidly being degraded by charcoal production, wood harvesting, burning and agriculture.

botanical specialist report january 2013 ranobe mine rpt english cb0503… · aristida sp. indet....

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