Marlborough Sounds Resource Management Plan They include coastal, estuarine, riparian, ultramafic, subalpine and seral shrublands; coastal, ultramafic riparian, estuarine and alpine tussocklands, herbfields and rocklands (especially on bluffs); dunelands, estuarine rushlands, and various wetland communities. Disturbance and loss of indigenous vegetation cover correlates very well with altitude. Mid-altitude and upland forests, and alpine communities are still largely intact. Coastal and lowland forests have been extensively compromised and are fragmented or lost over much of the Sounds, especially in the drier parts; however a few exceptional areas are still intact. Alluvial communities, especially forests and wetlands, have been drastically compromised with very little remaining - almost regionally extinct. D’Urville Island, Mt Stokes and the forests of the upper Pelorus Valley and Tennyson Inlet retain much of their indigenous cover. They make a major contribution to the natural character of the Sounds as a whole. Lowland hill country with regenerating and old growth indigenous forest provides much natural character, despite a long history of modification and loss. The overall pattern is that natural character is better retained in the west and at higher altitudes. These western areas are representative of some of the natural character intrinsic to the Sounds and their preservation and restoration would contribute greatly to the Sounds as a whole. Where indigenous vegetation areas exist in the east, in low altitude areas of the Pelorus catchment, and in the low relief areas of outer Pelorus Sound, they break up the predominately modified landscape and make a strong contribution to the natural character of the Sounds as a whole. 2. Distinctive Biota, Natural Biodiversity, Productivity The ecological districts that make up the Sounds are further subdivided into eleven distinct terrestrial ecosystems, each with a unique combination of geology, landforms, climate, natural communities and biota. There is very high overall natural biodiversity due to habitat heterogeneity and the presence of island refuges. Generally natural productivity is moderate throughout the Sounds, with limited areas of extremely high productivity (seabird islands) and of very low productivity (ultramafic areas). The area contains over a third of New Zealand’s native plants species. 3. Biotic Patterns Natural biotic patterns are strongly influenced by intricate landforms, substrate and strong climatic gradients between the Inner and Outer Sounds, eastern and western Sounds, lowlands and uplands (eg; Pelorus lowlands with moderately high rainfall/low exposure, compared to the Cook Strait narrows with low rainfall/high exposure). Although relatively small in extent, the non-forest communities and alluvial communities of the Sounds are extremely important in adding to community and species biodiversity, many being highly distinctive and confined to the North Marlborough - Sounds - Cook Strait areas, providing vital habitat to numerous App Two - 6