A palaeoecological test of the land-use hypothesis for recent lake acidification in South-West Norway using hill-top lakes

1990 ◽  
Vol 4 (1) ◽  
Author(s):  
H.J.B. Birks ◽  
Frode Berge ◽  
J.F. Boyle ◽  
B.F. Cumming
Nature ◽  
1986 ◽  
Vol 322 (6075) ◽  
pp. 157-158 ◽  
Author(s):  
Vivienne J. Jones ◽  
Anthony C. Stevenson ◽  
Richard W. Battarbee
Keyword(s):  
Land Use ◽  

Oryx ◽  
1996 ◽  
Vol 30 (3) ◽  
pp. 207-217 ◽  
Author(s):  
Timothy G. O'Brien ◽  
Margaret F. Kinnaird

Bukit Barisan Selatan National Park in south-west Sumatra is one of the largest protected areas in Sumatra and thus of considerable importance to the conservation of biodiversity in Indonesia. Until recently, little was known of the wildlife in the park. The authors' surveys document the presence of an intact community of the birds and mammals known to occur in lowland Sumatran rain forests. While hunting and collection of forest products threaten a number of plant and animal species in the park, the primary threat to the park's integrity is from agricultural encroachment and expansion of enclaves beyond their boundaries. The future survival of Bukit Barisan National Park and its wildlife requires that active measures be taken to curb non-sustainable exploitation of plants and wildlife. It will also be necessary to resolve land-use conflicts with communities in, and adjacent to, the park.


This is a palaeolimnological study of two Norwegian soft-water lakes, one receiving high, the other low, deposition of sulphur and nitrogen compounds. At the site with low acid deposition inferred pH has oscillated between 5.6 and 5.9 and there is little evidence of atmospheric contamination. At the site with high acid deposition, many centuries of stability are followed by a rapid acidification from pH around 5 in 1900 to the present (1986) level of pH 4.4. In this lake, the sedimentary record indicates a close connection between acid deposition and recent lake acidification.


Iron Age de-settlement in Halsingland, Northern Sweden, can be regarded as a good analogue for the possible effects of land-use and vegetational changes on lake acidification without the effect of contemporary atmospheric pollution. Pollen analyses were used to identify vegetational change associated with a de-settlement period ca . 500 A. D. and diatom analyses to assess if there was any associated change in lake-water pH. A clear settlement horizon was found in the two lakes studied, indicating catchment disturbance associated with Iron Age agriculture. There was no change, however, in diatom reconstructed pH after de-settlement, during vegetation regeneration, when it has been postulated that the build up of raw humus and change of ion-exchange conditions would result in acidification. Importantly, one of the lakes began to acidify, before liming, under contemporary levels of acid deposition.


Author(s):  
Dada Ibilewa ◽  
Mustapha Aliyu ◽  
Usman O. Alalu ◽  
Taiwo Hassan Abdulrasheed

Geo-spatial assessment of land use/cover dynamics in Akoko South West Local Government was instigated to bridge the knowledge gap created by data deficiency on the nature, scope and magnitude of land use/cover change in the area. This was done through the analysis of Landsat images of three epochs from 2000 through 2010 to 2020. The processing of the satellite images was done in ArcGIS 10.8 while the analysis and 2030 projection was done in Microsoft office excel using the result from the analysis. QGIS was used to remove the scan lines error on the 2010 image. The result showed increasing built-up area, reducing vegetation and farmlands and diminishing rock outcrops. The changes vary among the different classification characteristics. The increasing change in the second epoch was higher in built up areas while rock outcrops increased in the first epoch. Farmland and vegetation were on reducing trend throughout the study period. However, the moderate change observed in the second epoch for the two land cover classes were not as significant as the first epoch. Government policies on forest reserve should strictly be adhered to in order to preserve the vegetation in the area. People of the area should be advised to diversify their economy in order to avoid total dependence on the forest reserve.


2019 ◽  
Vol 28 (3) ◽  
pp. 572-580
Author(s):  
Nayombe Moto Theophilus Mukete

The article is devoted to investigating a number of issues within the forest landscape of the Fako-Meme, south west region of Cameroon. An assessment of the history of economic development and use of forest in the studied territory was carried out. It was observed that the rate at which these forests are been hewn down for various purposes under the pretext of development leaves much to be desired. The deforestation of the forest with the attendant problems of resource degradation, environmental mutation is a cause for alarm. In order to understand the mutations taking place in the forest landscape, the history of forest use in 4 different periods: 1) the pre-colonial era (before the arrival of European explorers), (2) German colonial rule (1884-1916), (3) British colonial rule (1916-1961) and (4) Independence and post Independence Cameroon (1961-present day). It was observed that during the pre-colonial era the forest landscapes were very stable. Forest degradation in the territory started with the introduction of extensive mechanized agriculture introduced by the colonial masters through the opening of large agro-industrial plantations of rubber, palms and bananas. This forest ecological region suffers from a number of challenges. These problems were investigated in detail with proposals made for the sustainable management of forest resources in this forest ecosystem situated in    the heart of the humid tropical region of the South West of Cameroon. These forests provide for a wide range of human needs ; medicine, timber , fuel wood, non- timber forest products (NTFPs), food crop production and cash crop cultivation. The pattern of land-use change in the Fako-Meme region was studied in three distinctive periods (1978, 2000 and 2015). The results revealed that anthropogenic activities have been systematically raping the forest landscapes so that the environments are only a skeleton or shadow of their former selves. This is an ecological region in which forest gives way to farmlands and plantations. In this respect, we see that what was a forest landscape in the past is now consisting of a succession of cocoa farms, palm, rubber as well as other economic cash crop plantations, with cocoa being the most important cash crop in the region. Evidence from our analysis reveals that this region   has lost 42% of its forest cover within the period 1978-2015. This dynamic can be considered catastrophic. If this trend continues uninterruptedly in the region, then in 60-70 years, the Fako-Meme and the slopes of Mount Cameroon will remain without forest. It is easy to imagine the consequences of this. The study calls for urgent adaptive environmental strategies for the sustainable management of forest and its resources in the region.


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