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Land use changes in Gishwati forest and its impact on biodiversity Full text
2009
Uwimana, M.F. | Duren, I. van | Laake, P. van | Leeuw, Jan de
Land use changes in Gishwati forest and its impact on biodiversity Full text
2009
Uwimana, M.F. | Duren, I. van | Laake, P. van | Leeuw, J. de
Fire and land use effects on biodiversity in the southern Sumatran wetlands Full text
2009
rizki pandu permana | robiyanto hendro susanto | meilanie buitenzorgy | unna chokkalingam | suyanto | iwan kurniawan
We studied the long-term effects of an intensified fire regime following logging and altered land use practices on the biodiversity and successional dynamics of forests on three sites (Sugihan, Mesuji, and Pampangan) of roughly 300 km2 each, distributed across the continuous wetland ecosystem of southern Sumatra. Satellite image analysis and ecological and socio-economic surveys were combined to reveal the vegetation characteristics, and links to fire, land use history, and site conditions. Since the 1970sâ??1980s, this ecosystem has been subject to widespread repeated fires associated with or following intensive logging, transmigration, and plantation development, sonor or swamp rice cultivation, and other local resource use. Burn traces in the soil profile suggest that earlier fire episodes were far more limited in their coverage than the severe and frequent burning of the recent past. The result has been a rapid transformation from mature, high mixed species forests to sedge grasslands, savannas, and open to dense mono-specific stands of fast-growing fire-adapted species. Current vegetation types are largely differentiated by structural rather than compositional differences, which are significantly linked to fire frequency or time since last fire. The more frequent and recent the fires, the more open the landscape, with reduced density and basal area of trees. At present, the area is very species-poor. Most patches in Sugihan and Mesuji are dominated by a single speciesâ??Melaleuca cajuputiâ??in the tree, sapling, and seedling layers except for degraded mixed forests which have a mix of species in all layers. Degraded mixed forests were more recently logged and burnt just once in 1991. Pampangan has a different species composition with all patches dominated by Combretocarpus rotundatus in the tree layer, which is linked to greater organic matter depth. However, in the deep peats of Pampangan the sapling and seedling layers are also dominated by Melaleuca cajuputi in most patches suggesting a future shift in overstory composition to this more freshwater wetland-adapted species. This compositional shift is likely due to peast subsidence and increased likelihood of flooding following repeated burning. The live fuel structure with tall, dense lower strata to mid-strata of flammable herbaceous and woody species and scattered to dense tree cover renders all the vegetation types extremely fire-prone in dry years. The flammable vegetation combined with increased development and population pressures on these last frontiers makes contiued wides pread fires highly likely. This will lead to further simplification of species composition and structure, and degradation of the landscape into treeless plains. Resource depletion has led to falling incomes and fewer livelihood options in southern Sumatra. Fires and their negative impacts have expanded into the northern provinces of Sumatra as well with timber and oil palm plantation development and/or migrating populations in search of livelihood options. Given the large contribution of peatland fires to trans-boundary haze, carbon emissions, and global warming, reducing and controlling fires in the wetlands of Sumatra is of high priority. Fire management issues and options for the wetlands of southern Sumatra are discussed | Unna Chokkalingam et al., 'Fire and land use effects on biodiversity in the southern Sumatran wetlands', Tropical Fire Ecology, pp.355-385, Springer Berlin Heidelberg, 2009
Show more [+] Less [-]Bioenergy to Biodiversity: Downscaling scenarios of land use change Full text
2009
MacKenzie, Ian | Dendoncker, Nicolas
Bioenergy crops are a key component of Scotland’s strategy to meet 2050 carbon emissions targets. The introduction of these crops could have large scale impacts on the biodiversity of lowland farmland. These impacts depend on the change in land use which in turn is governed by a wide range of social, economic and environmental factors. European scale scenarios have been used to model these factors and estimate future land uses. Divergent cenarios provide narratives that explore the outcome of different policy assumptions and can be used to explore an uncertain future and its potential impacts on biodiversity. Here we focus on SRC willow and Miscanthus as examples of woody and non wood bioenergy crops. The area of land modelled by the European scenarios is downscaled to the land parcel level. To achieve this, a methodology is developed that uses simple allocation rules based on the assumptions of the core scenarios. The results of the downscaling are then used to investigate the impact on biodiversity of different scenario assumptions at 2020 and 2050. The results show that only a small amount of agricultural land may be available in the strictest environmental scenarios. Downscaling reveals different spatial patterns of biodiversity networks arising from divergent policy assumption. Therefore the methodology provides a link between European land use change and landscape scale changes to biodiversity.
Show more [+] Less [-]Quantifying the effect of catchment land use and water nutrient concentrations on freshwater river and stream biodiversity Full text
2009
Weijters, M.J. | Janse, J.H. | Alkemade, R. | Verhoeven, J.T.A.
1.A major threat to freshwater taxon diversity is the alteration of natural catchment Land use into agriculture, industry or urban areas and the associated eutrophication of the water. In order to stop freshwater biodiversity loss, it is essential to quantify the relationships between freshwater diversity and catchment Land use and water nutrient concentrations.2.A literature survey was carried out on biodiversity data from rivers and streams. Fish and macroinvertebrates were selected as focal groups as they are widely used as indicator species of river and stream health. Only published data were selected that (a) compared data found at impaired sites with a pristine reference situation (either in time or space), (b) clearly defined the stressors studied (Land use cover and/or nutrient concentrations), and (c) clearly defined biodiversity (number of native species, species lists or IBI-scores).3.The number of native taxa found in each study was transferred in an index of relative taxon richness (RTR) ranging from 0 (severely altered) to 100 (pristine reference conditions). Only those taxa were included that were (at least) present in the most pristine situation. This made it possible to combine, compare and analyse results from different studies. Catchment Land use was expressed as the percentage of non-natural Land use (agriculture, industry, housing or mining). As a measure of nutrients, the concentrations of NO₃, NH₄, PO₄, total N and total P in the river and stream water were used.4.Over 240 published articles have been studied, but only 22 met the criteria described above and could be used for further analysis.5.This study showed that altered catchment Land use has a major effect on freshwater biodiversity and that the rate of species loss is serious; on average every 10% of lost natural catchment Land use cover leads to a loss of almost 6% (±0.83) of the native freshwater fish and macroinvertebrate species.
Show more [+] Less [-]Effects of land-use change on productivity depend on small-scale plant species diversity Full text
2009
Gross, Nicolas | Bloor, Juliette M.G. | Louault, Frédérique | Maire, Vincent | Soussana, Jean-François
Understanding the interplay between land-use change, species diversity and ecosystem function is critical for the prediction of global change impacts on ecosystem services. Biodiversity experiments with artificial species assemblages have shown that community-scale species richness may affect ecosystem productivity and spatial stability. However, the use of synthetic communities with controlled levels of species density for biodiversity experiments has been criticised and their relevance for natural communities has been questioned. Here, we use a land-use change experiment to investigate the biodiversity effects on production within managed, upland grasslands. We examine species diversity and productivity at both the small plant-neighbourhood scale (14×14 cm) and the field scale (15 m×25 m) for two land-use trajectories under field conditions: intensification through fertilisation, and extensification through the cessation of mowing. Both intensification and extensification were associated with a decrease in species number, but the magnitude of this decrease was greater at the small scale. Extensification was associated with a decrease in small-scale productivity whereas intensification had no significant effect on small-scale productivity. Effects of land-use treatments on biomass production were mediated by variation in small-scale species number; species number showed a significant positive relationship with small-scale productivity within each land-use treatment. Furthermore, species number was associated with a decrease in the variance of small-scale green biomass. In contrast, no species diversity effects were found on productivity at the field scale. Instead, field-scale species diversity decreased with increase in the total above-ground biomass (green biomass+litter). This study demonstrates that biodiversity effects can be observed under field conditions at the small scale and may play an important role for ecosystem functioning and stability even in low-diversity plant communities.
Show more [+] Less [-]The relevance of farming and farmland for maintaining the landscape and biodiversity of the Sava floodplains
2009
Zingstra, H.L. | Kis, A. | Ribaric, A. | Bakovic, D. | Ilijas, I. | Jeremic, J. | Galambos, L. | Szabados, K. | Vukelic, M. | Predic, T.
This report presents the results of the activities the land use working group performed in the frame of the Life 3rd countries project: “Protection of Biodiversity of the Sava River Basin Floodplains” (LIFE06 TCY INT 246) as mentioned under task C of the project proposal. The following deliverables of Task C are included in this report: - Assessment of traditional and ongoing land use activities and their relevance for maintaining the landscape and biodiversity ( chapter 5, 6 and 7) - Analysis of market conditions and product chains. ( chapter 8) - Action plan for restoring, maintenance and management of floodplain areas including guidelines for land use practices ( chapter 10) - Concepts for innovative land-use practices ( chapter 9) - Recommendations for setting up a support/incentives scheme for continuing traditional land uses ( chapter 9) The analysis of the land uses is relevant because in combination with the information about the distribution of habitats and species it provides an essential bases for the identification of threats and the design of the required restoration and management measures to secure favourable conservation status of the habitats and species. Given the time needed to make a full inventory of the land uses of all 49 project sites along the Sava River it was decided to focus on those sites that were indicated as most valuable for biodiversity. The sites are selected in close communication with the biodiversity working group because and selected because of the need to improve the protection status and to design management and restoration plans for these sites.
Show more [+] Less [-]The relevance of farming and farmland for maintaining the landscape and biodiversity of the Sava floodplains
2009
Zingstra, H.L. | Kis, A. | Ribaric, A. | Bakovic, D. | Ilijas, I. | Jeremic, J. | Galambos, L. | Szabados, K. | Vukelic, M. | Predic, T.
This report presents the results of the activities the land use working group performed in the frame of the Life 3rd countries project: “Protection of Biodiversity of the Sava River Basin Floodplains” (LIFE06 TCY INT 246) as mentioned under task C of the project proposal. The following deliverables of Task C are included in this report: - Assessment of traditional and ongoing land use activities and their relevance for maintaining the landscape and biodiversity ( chapter 5, 6 and 7) - Analysis of market conditions and product chains. ( chapter 8) - Action plan for restoring, maintenance and management of floodplain areas including guidelines for land use practices ( chapter 10) - Concepts for innovative land-use practices ( chapter 9) - Recommendations for setting up a support/incentives scheme for continuing traditional land uses ( chapter 9) The analysis of the land uses is relevant because in combination with the information about the distribution of habitats and species it provides an essential bases for the identification of threats and the design of the required restoration and management measures to secure favourable conservation status of the habitats and species. Given the time needed to make a full inventory of the land uses of all 49 project sites along the Sava River it was decided to focus on those sites that were indicated as most valuable for biodiversity. The sites are selected in close communication with the biodiversity working group because and selected because of the need to improve the protection status and to design management and restoration plans for these sites.
Show more [+] Less [-]The dimensions of land use change in rural landscapes: lessons learnt from the GB countryside surveys Full text
2009
Petit, Sandrine
Rural landscapes are highly dynamic and their change impacts on a number of ecological processes such as the dynamics of biodiversity. Although a substantial amount of research has focused on quantifying these changes and their impact on biodiversity, most studies have focused on single dimensions of land use change. This lack of integration in land use change studies can be explained by the fact that data on the spatial, temporal, and ecological dimensions of land use are seldom available for the same geographical location. In this paper, the benefits of taking into account these three dimensions are illustrated with results derived from the Great Britain Countryside Surveys (CS), a large-scale monitoring programme designed to assess change in the extent and ecological condition of British habitats. The overview of CS results presented in this paper shows that (1) changes in land use composition will translate into a variety of spatial patterns; (2) the temporal stability of land use is often lower than can be expected; and (3) there can be large-scale shifts in the ecological condition of the land use types that form our rural landscapes. The benefits of integrated rural landscape studies are discussed in the context of other national monitoring programmes.
Show more [+] Less [-]The linkages between land use change, land degradation and biodiversity across East Africa Full text
2009
Maitima, J.M. | Mugatha, Simon M. | Reid, Robin S. | Gachimbi, L.N. | Majule, A.E. | Lyaruu, H. | Pomery, D. | Mugisha, S. | Mathai, S.
Land use changes in East Africa have transformed land cover to farmlands, grazing lands, human settlements and urban centers at the expense of natural vegetation. These changes are associated with deforestation, biodiversity loss and land degradation. A synthesis of results of long term research by an interdisciplinary team reveals the linkages between land use change, biodiversity loss and land degradation. The results indicate that as native vegetation is lost, indigenous plant and animal biodiversity and plant cover are lost. Pastoralism maintains native plant and animal species more effectively than crop cultivation. As croplands expand, soil fertility and moisture drops and soils erode more easily. Farmers who grow many crops conserve native plant species better than those who grow only one crop. Increased crop diversity encourages regeneration of indigenous plant species. Moderate farming as in the less intensive low input rainfed mixed crop farming, in less forested areas increases tree cover thus increasing the biodiversity. Farmers’ who combine livestock rearing with cropping, use livestock manure to replenish soil nutrients in their farms and are thus able to maintain higher productivity. Farming in grasslands, woodlands and bushland areas where there are fewer trees, increases the diversity of habitats due to introduction of agrosystems that attract new species of birds. However, if the farming is intensified and the diversity of habitats is reduced biodiversity is also reduced. This paper presents findings of the investigations on these linkages in a diverse farming and herding systems ranging from lowlands to high mountains land uses.
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