The Cubango-Okavango River Basin Multi-Sector Investment Opportunities Analysis

The Okavango River Basin is a hotspot of bat diversity that requires urgent and adequate protection. To advise future conservation strategies, we investigated the relative importance of a range of potential environmental drivers of bat species richness and functional community composition in the Okavango River Basin. During annual canoe transects along the major rivers, originating in the central Angolan highlands, we recorded more than 25,000 bat echolocation calls from 2015 to 2018. We corrected for possible biases in sampling design and effort. Firstly, we conducted rarefaction analyses of each survey year and sampling appeared to be complete, apart from 2016. Secondly, we used total activity as a measure of sample effort in mixed models of species richness. Species richness was highest in the Angola Miombo Woodlands and at lower elevations, with higher minimum temperatures. In total, we identified 31 individual bat species. We show that even when acoustic surveys are conducted in remote areas and over multiple years, it is possible to correct for biases and obtain representative richness estimates. Changes in habitat heterogeneity will have detrimental effects on the high richness reported here and human land-use change, specifically agriculture, must be mediated in a system such as the Angolan Miombo Woodland.

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RESPONSE OF RIPARIAN VEGETATION IN AUSTRALIA"S LARGEST RIVER BASIN TO INTER AND INTRA-ANNUAL CLIMATE VARIABILITY AND FLOODING AS QUANTIFIED WITH LANDSAT AND MODIS

ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences ◽

10.5194/isprsarchives-xli-b8-577-2016 ◽

2016 ◽

Vol XLI-B8 ◽

pp. 577-578

Author(s):

M. Broich ◽

M. G. Tulbure

Keyword(s):

River Basin ◽

Vegetation Dynamics ◽

Riparian Vegetation ◽

Rainfall Variability ◽

Annual Rainfall ◽

Spatially Explicit ◽

Rainfall Gradient ◽

Vegetation Degradation ◽

Millennium Drought ◽

Okavango River

Australia is a continent subject to high rainfall variability, which has major influences on runoff and vegetation dynamics. However, the resulting spatial-temporal pattern of flooding and its influence on riparian vegetation has not been quantified in a spatially explicit way. Here we focused on the floodplains of the entire Murray-Darling Basin (MDB), an area that covers over 1M km2, as a case study. The MDB is the country’s primary agricultural area with scarce water resources subject to competing demands and impacted by climate change and more recently by the Millennium Drought (1999–2009). Riparian vegetation in the MDB floodplain suffered extensive decline providing a dramatic degradation of riparian vegetation. We quantified the spatial-temporal impact of rainfall, temperature and flooding patters on vegetation dynamics at the subcontinental to local scales and across inter to intra-annual time scales based on three decades of Landsat (25k images), Bureau of Meteorology data and one decade of MODIS data. Vegetation response varied in space and time and with vegetation types, densities and location relative to areas frequently flooded. Vegetation degradation trends were observed over riparian forests and woodlands in areas where flooding regimes have changed to less frequent and smaller inundation extents. Conversely, herbaceous vegetation phenology followed primarily a ‘boom’ and ‘bust’ cycle, related to inter-annual rainfall variability. Spatial patters of vegetation degradation changed along the N-S rainfall gradient but flooding regimes and vegetation degradation patterns also varied at finer scale, highlighting the importance of a spatially explicit, internally consistent analysis and setting the stage for investigating further cross-scale relationships. Results are of interest for land and water management decisions. The approach developed here can be applied to other areas globally such as the Nile river basin and Okavango River delta in Africa or the Mekong River Basin in Southeast Asia.

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RESPONSE OF RIPARIAN VEGETATION IN AUSTRALIA"S LARGEST RIVER BASIN TO INTER AND INTRA-ANNUAL CLIMATE VARIABILITY AND FLOODING AS QUANTIFIED WITH LANDSAT AND MODIS

ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences ◽

10.5194/isprs-archives-xli-b8-577-2016 ◽

2016 ◽

Vol XLI-B8 ◽

pp. 577-578

Author(s):

M. Broich ◽

M. G. Tulbure

Keyword(s):

River Basin ◽

Vegetation Dynamics ◽

Riparian Vegetation ◽

Rainfall Variability ◽

Annual Rainfall ◽

Spatially Explicit ◽

Rainfall Gradient ◽

Vegetation Degradation ◽

Millennium Drought ◽

Okavango River

Australia is a continent subject to high rainfall variability, which has major influences on runoff and vegetation dynamics. However, the resulting spatial-temporal pattern of flooding and its influence on riparian vegetation has not been quantified in a spatially explicit way. Here we focused on the floodplains of the entire Murray-Darling Basin (MDB), an area that covers over 1M km2, as a case study. The MDB is the country’s primary agricultural area with scarce water resources subject to competing demands and impacted by climate change and more recently by the Millennium Drought (1999–2009). Riparian vegetation in the MDB floodplain suffered extensive decline providing a dramatic degradation of riparian vegetation. We quantified the spatial-temporal impact of rainfall, temperature and flooding patters on vegetation dynamics at the subcontinental to local scales and across inter to intra-annual time scales based on three decades of Landsat (25k images), Bureau of Meteorology data and one decade of MODIS data. Vegetation response varied in space and time and with vegetation types, densities and location relative to areas frequently flooded. Vegetation degradation trends were observed over riparian forests and woodlands in areas where flooding regimes have changed to less frequent and smaller inundation extents. Conversely, herbaceous vegetation phenology followed primarily a ‘boom’ and ‘bust’ cycle, related to inter-annual rainfall variability. Spatial patters of vegetation degradation changed along the N-S rainfall gradient but flooding regimes and vegetation degradation patterns also varied at finer scale, highlighting the importance of a spatially explicit, internally consistent analysis and setting the stage for investigating further cross-scale relationships. Results are of interest for land and water management decisions. The approach developed here can be applied to other areas globally such as the Nile river basin and Okavango River delta in Africa or the Mekong River Basin in Southeast Asia.

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Relationships between NDVI , river discharge and climate in the Okavango River Basin region

International Journal of Climatology ◽

10.1002/joc.7267 ◽

2021 ◽

Author(s):

O. Moses ◽

R. C. Blamey ◽

C. J. C. Reason

Keyword(s):

River Basin ◽

River Discharge ◽

Okavango River ◽

Basin Region

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Investigating nitrate retention capacity, elementary and mineral composition of Kalahari sandy soils at Mashare farm in Namibia, Okavango river basin

Scientific African ◽

10.1016/j.sciaf.2019.e00193 ◽

2019 ◽

Vol 6 ◽

pp. e00193

Author(s):

Andrea Vushe ◽

Maggina Amutenya

Keyword(s):

Mineral Composition ◽

River Basin ◽

Sandy Soils ◽

Retention Capacity ◽

Nitrate Retention ◽

Okavango River

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Climate change impacts on river basin and freshwater ecosystems: some observations on challenges and emerging solutions

Journal of Water and Climate Change ◽

10.2166/wcc.2012.006 ◽

2012 ◽

Vol 3 (3) ◽

pp. 171-184 ◽

Cited By ~ 12

Author(s):

Avi Ostfeld ◽

Stefano Barchiesi ◽

Matthijs Bonte ◽

Carol R. Collier ◽

Katharine Cross ◽

...

Keyword(s):

Climate Change ◽

Water Management ◽

Case Studies ◽

River Basin ◽

Climate Change Impacts ◽

River Basin Management ◽

Freshwater Ecosystems ◽

Delaware River ◽

Change Models ◽

Okavango River

Despite uncertainty pertaining to methods, assumptions and input data of climate change models, most models point towards a trend of an increasing frequency of flooding and drought events. How these changes reflect water management decisions and what can be done to minimize climate change impacts remains unclear. This paper summarizes and extends the workshop outcomes on ‘Climate Change Impacts on Watershed Management: Challenges and Emerging Solutions’ held at the IWA World Water Congress and Exhibition, Montréal, 2010, hosted by the IWA Watershed and River Basin Management Specialist Group. The paper discusses climate change impacts on water management of freshwater ecosystems and river basins, and illustrates these with three case studies. It is demonstrated through the case studies that engagement of relevant stakeholders is needed early in the process of building environmental flows and climate change decision-making tools, to result in greater buy-in to decisions made, create new partnerships, and help build stronger water management institutions. New alliances are then created between water managers, policy makers, community members, and scientists. This has been highlighted by the demonstration of the Pangani integrated environmental flow assessment, through the Okavango River Basin case study, and in the more participatory governance approach proposed for the Delaware River Basin.

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