Influence of cultivation, settlements and water sources on wildlife distribution and habitat selection in south-east Kajiado, Kenya

2008 ◽  
Vol 35 (2) ◽  
pp. 117-124 ◽  
Author(s):  
J. K. MWORIA ◽  
J. I. KINYAMARIO ◽  
J. M. GITHAIGA
Keyword(s):  
Land Use ◽  
Vegetation Type ◽  
Land Use Changes ◽  
Water Sources ◽  
Small Scale ◽  
Grass Cover ◽  
Wet Season ◽  
Seasonal Ponds ◽  
Land Use Types ◽  
Wildlife Distribution

SUMMARYIn Kenya, lands surrounding wildlife protected areas (PAs), referred to as dispersal areas, have undergone widespread land use changes, but these have been little studied. This study investigated impacts of different land use types on wildlife distribution and composition. Transect data from stratified random sampling based on land use and vegetation type were analysed using correlation and canonical correspondence analysis (CCA). Household density and cultivation intensity were negatively correlated with grass cover and were greatest on small-scale farms and lowest in a dedicated PA. Three patterns of wildlife distribution were identified. Wildlife density in communal grazing and the PA was significantly higher than on other land use types. While most wildlife used pastoral ranches in the wet season, larger herbivores moved to the PA during the dry season. Wildlife density along the grass cover gradient, which was a disturbance gradient, was dome shaped, indicating that wildlife tolerated moderate levels of disturbance. The primary factors influencing wildlife distribution were vegetation type and proximity to water sources in the dry and wet seasons, respectively. The apparent anomaly in the wet season is attributed to wildlife moving from Chyulu, which lacked seasonal ponds, to the lowland Masaai ranches, which had plenty of ponds. In both seasons, cattle density was the most important secondary factor. To mitigate declining wildlife trends, management should ensure a heterogeneity of vegetation types is maintained and wildlife retain access to seasonal water sources.

scholarly journals A Model-Based Tool for Assessing the Impact of Land Use Change Scenarios on Flood Risk in Small-Scale River Systems—Part 1: Pre-Processing of Scenario Based Flood Characteristics for the Current State of Land Use

Hydrology ◽  
2021 ◽  
Vol 8 (3) ◽  
pp. 102
Author(s):  
Frauke Kachholz ◽  
Jens Tränckner
Keyword(s):  
Land Use ◽  
River Flow ◽  
Land Use Changes ◽  
Small Rivers ◽  
Small Scale ◽  
Model Parameters ◽  
Ungauged Catchments ◽  
Model Based ◽  
Current State ◽  
The Impact

Land use changes influence the water balance and often increase surface runoff. The resulting impacts on river flow, water level, and flood should be identified beforehand in the phase of spatial planning. In two consecutive papers, we develop a model-based decision support system for quantifying the hydrological and stream hydraulic impacts of land use changes. Part 1 presents the semi-automatic set-up of physically based hydrological and hydraulic models on the basis of geodata analysis for the current state. Appropriate hydrological model parameters for ungauged catchments are derived by a transfer from a calibrated model. In the regarded lowland river basins, parameters of surface and groundwater inflow turned out to be particularly important. While the calibration delivers very good to good model results for flow (Evol =2.4%, R = 0.84, NSE = 0.84), the model performance is good to satisfactory (Evol = −9.6%, R = 0.88, NSE = 0.59) in a different river system parametrized with the transfer procedure. After transferring the concept to a larger area with various small rivers, the current state is analyzed by running simulations based on statistical rainfall scenarios. Results include watercourse section-specific capacities and excess volumes in case of flooding. The developed approach can relatively quickly generate physically reliable and spatially high-resolution results. Part 2 builds on the data generated in part 1 and presents the subsequent approach to assess hydrologic/hydrodynamic impacts of potential land use changes.

scholarly journals Evaluating the Contribution of Trees outside Forests and Small Open Areas to the Italian Landscape Diversification during the Last Decades

Forests ◽  
2018 ◽  
Vol 9 (11) ◽  
pp. 701 ◽  
Author(s):  
Lorenzo Sallustio ◽  
Marco di Cristofaro ◽  
Maaz Hashmi ◽  
Matteo Vizzarri ◽  
Tommaso Sitzia ◽  
...  
Keyword(s):  
Land Use ◽  
Large Scale ◽  
Land Use Changes ◽  
Canopy Cover ◽  
Integrated Approach ◽  
Small Scale ◽  
Trees Outside Forests ◽  
Large Scale Assessment ◽  
Average Size ◽  
Policy And Planning

Land use by humans strongly alters the landscape mosaic, either by reducing or increasing its heterogeneity. One of the most recent and widespread land use changes in Europe has been the spontaneous reforestation of marginal agricultural lands. These primarily affected small landscape patches, such as trees outside forests (TOF) and small open areas (SOA), often represent the most diversifying features of landscape’ structures. Nevertheless, only small-scale studies can be found in the literature and thus it remains a relatively unexplored issue. Integrating inventory and cartographic approaches, this work assesses changes in abundance, coverage, and average size of small patches in Italy between 1990 and 2013. Main results showed an overall increase in number and coverage of small patches during the reference period. The average patch size remains unaltered for TOF but decreases significantly for SOA, due to trees encroachment and canopy cover increasing in forests. Our findings confirm the important changes in Mediterranean land mosaics and contribute to a better understanding of current conditions and recent trends regarding TOF and SOA. The integrated approach has proven to be helpful for the large-scale assessment of small patches dynamics, representing a viable monitoring tool to encourage the inclusion of small patches in landscape policy and planning.

scholarly journals Effects of Climate and Land Use changes on Vegetation Dynamics in the Yangtze River Delta, China Based on Abrupt Change Analysis

2020 ◽  
Vol 12 (5) ◽  
pp. 1955
Author(s):  
Lei Wan ◽  
Huiyu Liu ◽  
Haibo Gong ◽  
Yujia Ren
Keyword(s):  
Land Use ◽  
Vegetation Dynamics ◽  
Abrupt Change ◽  
Land Use Changes ◽  
Yangtze River Delta ◽  
Change Analysis ◽  
Land Use Types ◽  
Natural Land ◽  
Abrupt Change Analysis ◽  
Relationship Of

Vegetation dynamics is thought to be affected by climate and land use changes. However, how the effects vary after abrupt vegetation changes remains unclear. Based on the Mann-Kendall trend and abrupt change analysis, we monitored vegetation dynamics and its abrupt change in the Yangtze River delta during 1982–2016. With the correlation analysis, we revealed the relationship of vegetation dynamics with climate changes (temperature and precipitation) pixel-by-pixel and then with land use changes analysis we studied the effects of land use changes (unchanged or changed land use) on their relationship. Results showed that: (1) the Normalized Vegetation Index (NDVI) during growing season that is represented as GSN (growing season NDVI) showed an overall increasing trend and had an abrupt change in 2000. After then, the area percentages with decreasing GSN trend increased in cropland and built-up land, mainly located in the eastern, while those with increasing GSN trend increased in woodland and grassland, mainly located in the southern. Changed land use, except the land conversions from/to built-up land, is more favor for vegetation greening than unchanged land use (2) after abrupt change, the significant positive correlation between precipitation and GSN increased in all unchanged land use types, especially for woodland and grassland (natural land use) and changed land use except built-up land conversion. Meanwhile, the insignificant positive correlation between temperature and GSN increased in woodland, while decreased in the cropland and built-up land in the northwest (3) after abrupt change, precipitation became more important and favor, especially for natural land use. However, temperature became less important and favor for all land use types, especially for built-up land. This research indicates that abrupt change analysis will help to effectively monitor vegetation trend and to accurately assess the relationship of vegetation dynamics with climate and land use changes.

scholarly journals Conflict between humans and elephants on private land in northern Kenya

Oryx ◽  
1994 ◽  
Vol 28 (2) ◽  
pp. 119-127 ◽  
Author(s):  
Chris R. Thouless
Keyword(s):  
Land Use ◽  
Protected Areas ◽  
Human Population ◽  
Water Sources ◽  
Small Scale ◽  
Private Land ◽  
Northern Kenya ◽  
Small Scale Farmers

About 3000 elephants live in the Laikipia/Sambnru region of northern Kenya – the largest remaining population outside the country's formal protected areas. The elephants occasionally kill or injure people, damage the crops of small-scale farmers, drive cattle away from water sources and cause a range of other problems for the human population. As a result, a number of elephants have been shot for control purposes in recent years and others have died as a result of poisoning, snares or spearing. The author examines the conflict between elephants and humans in areas of differing land use and makes suggestions for resolving at least some of the problems.

scholarly journals Using Landsat Thematic Mapper (TM) sensor to detect change in land surface temperature in relation to land use change in Yazd, Iran

Solid Earth ◽  
2016 ◽  
Vol 7 (6) ◽  
pp. 1551-1564 ◽  
Author(s):  
Sajad Zareie ◽  
Hassan Khosravi ◽  
Abouzar Nasiri ◽  
Mostafa Dastorani
Keyword(s):  
Land Use ◽  
Surface Temperature ◽  
Land Surface Temperature ◽  
Land Surface ◽  
Land Use Changes ◽  
Thermal Conditions ◽  
Kappa Coefficient ◽  
Thematic Mapper ◽  
Landsat Thematic Mapper ◽  
Land Use Types

Abstract. Land surface temperature (LST) is one of the key parameters in the physics of land surface processes from local to global scales, and it is one of the indicators of environmental quality. Evaluation of the surface temperature distribution and its relation to existing land use types are very important to the investigation of the urban microclimate. In arid and semi-arid regions, understanding the role of land use changes in the formation of urban heat islands is necessary for urban planning to control or reduce surface temperature. The internal factors and environmental conditions of Yazd city have important roles in the formation of special thermal conditions in Iran. In this paper, we used the temperature–emissivity separation (TES) algorithm for LST retrieving from the TIRS (Thermal Infrared Sensor) data of the Landsat Thematic Mapper (TM). The root mean square error (RMSE) and coefficient of determination (R2) were used for validation of retrieved LST values. The RMSE of 0.9 and 0.87 °C and R2 of 0.98 and 0.99 were obtained for the 1998 and 2009 images, respectively. Land use types for the city of Yazd were identified and relationships between land use types, land surface temperature and normalized difference vegetation index (NDVI) were analyzed. The Kappa coefficient and overall accuracy were calculated for accuracy assessment of land use classification. The Kappa coefficient values are 0.96 and 0.95 and the overall accuracy values are 0.97 and 0.95 for the 1998 and 2009 classified images, respectively. The results showed an increase of 1.45 °C in the average surface temperature. The results of this study showed that optical and thermal remote sensing methodologies can be used to research urban environmental parameters. Finally, it was found that special thermal conditions in Yazd were formed by land use changes. Increasing the area of asphalt roads, residential, commercial and industrial land use types and decreasing the area of the parks, green spaces and fallow lands in Yazd caused a rise in surface temperature during the 11-year period.

scholarly journals Soil carbon response to land-use change: Evaluation of a global vegetation model using meta-data

2016 ◽  
Author(s):  
Sylvia S. Nyawira ◽  
Julia E. M. S. Nabel ◽  
Axel Don ◽  
Victor Brovkin ◽  
Julia Pongratz
Keyword(s):  
Land Use ◽  
Land Use Change ◽  
Soil Carbon ◽  
Vegetation Type ◽  
Land Use Changes ◽  
Climatic Conditions ◽  
Carbon Gain ◽  
Meta Data ◽  
Vegetation Models ◽  
Global Vegetation

Abstract. Global model estimates of soil carbon changes from past land-use changes remain uncertain. We develop an approach for evaluating dynamic global vegetation models (DGVMs) against existing observational meta-data on soil carbon changes following land-use change. Using the DGVM JSBACH, we perform idealized simulations where the entire globe is covered by one vegetation type, which then undergoes a land-use change to another vegetation type. We select the grid cells that represent the climatic conditions of the meta-data and compare the mean simulated soil carbon changes to the meta-data. Our simulated results show model agreement with the meta-data on the direction of changes in soil carbon for some, but not all land-use changes, while the magnitude of simulated changes is smaller than in the meta-data. The conversion of crop to forest results in soil carbon gain of 10 % and that of forest to crop to a loss of −15 % compared to a gain of 42 % and loss of −40 %, respectively, in the meta-data. However, the conversion of crop to grass results in a small soil carbon loss (−4 %), while the meta-data indicate a gain in soil carbon of 38 %. These model deviations from the meta-data are substantially reduced by explicitly accounting for crop harvesting and switching off burning in grasslands in the model. We conclude that our idealized simulation approach provides an appropriate framework for evaluating DGVMs against meta-data and that this evaluation helps to identify the causes of deviation of simulated soil carbon changes from the meta-data.

scholarly journals Larval Ecology of Anopheles Mosquitoes in Kudat, Sabah

2021 ◽  
Author(s):  
Wilfredo Escalante Aure ◽  
Nelia Palaria Salazar ◽  
Tock Hing Chua
Keyword(s):  
Land Use ◽  
Plasmodium Knowlesi ◽  
Land Use Changes ◽  
Rubber Tree ◽  
Tree Plantation ◽  
Breeding Sites ◽  
Larval Habitats ◽  
Anopheles Mosquitoes ◽  
Land Use Types ◽  
Average Maximum

The emergence of human Plasmodium knowlesi malaria appeared to have been precipitated by the displacement of the natural environment of macaques and Anopheles mosquitoes resulting from deforestation and land-use changes in Malaysia. A longitudinal survey of larval habitats was conducted from May 2015 to April 2016 in the District of Kudat, Sabah to better understand how these changes have affected mosquitoes across six land use categories. Larvae were collected by dipping and reared in the laboratory for the identification of adults. Five anopheline and three culicine species were present: Anopheles balabacensis, An. barbirostris, An. lesteri, An. borneensis, An. umbrosus, Aedes albopictus, Culex gelidus, and Toxorhynchites sp. An. balabacensis was found in all six land-use types. Biodiversity by genera was high in all land-use types. The relative importance of land use types and larval habitats as sources of potential vectors was analyzed by the Kruskal-Wallis H test by ranks. In decreasing order Anopheles larvae were found in rubber tree plantation > coconut plantation > clearing site > palm oil plantation > forest > settlement area. Important larval habitats were intermittent stream > ditch > pond > artificial container > puddle > river > slow-flowing stream. Eighteen breeding sites of An. balabacensis were within (500 m) the average maximum flight range of the species and houses at risk for malaria. Knowledge gained from the study can be used to assess the need for vector control in preventing the spread of P. knowlesi in vulnerable areas.  

scholarly journals Alluvial Water Source Capacity under the Climate Change and Other Impacts—Case Study of the Pek River in Serbia

Proceedings ◽  
2018 ◽  
Vol 2 (11) ◽  
pp. 596
Author(s):  
Dejan Dimkić ◽  
Stevan Prohaska ◽  
Bojan Stanković ◽  
Predrag Pajić
Keyword(s):  
Climate Change ◽  
Land Use ◽  
River Discharge ◽  
Land Use Changes ◽  
Water Source ◽  
Water Sources ◽  
Hydraulic Connection ◽  
Two Factors ◽  
Human Use

River discharge changes, in addition to natural variability, depend on several factors. Three factors are the most important: climate change (CC), changes in human use of water (HU), and land use changes (LU). River discharge has hydraulic connection with its alluvial sources and both are sensitive to climate and other changes. Alluvial water sources (ALWSs) are often used for water supplying purposes. The question is what could we expect in the future? Are they more or less sensible on climate change and other two factors, compare to river discharge changes, or it differ from case to case?

Development of a Multi-Hazard Landscape for Exposure and Risk Interpretation: The PRISM Approach

2019 ◽  
Vol 6 (1) ◽  
pp. 74-94 ◽  
Author(s):  
Kyle D. Buck ◽  
Kevin J. Summers ◽  
Stephen Hafner ◽  
Lisa M. Smith ◽  
Linda C. Harwell
Keyword(s):  
Land Use ◽  
Mitigation Strategies ◽  
Western United States ◽  
Small Scale ◽  
Land Area ◽  
Natural Systems ◽  
Multiple Hazards ◽  
Dynamic Risk ◽  
Land Use Types ◽  
Temporal Profiles

Background: Multi-hazard risk assessment has long been centered on small scale needs, whereby a single community or group of communities’ exposures are assessed to determine potential mitigation strategies. While this approach has advanced the understanding of hazard interactions, it is limiting on larger scales or when significantly different hazard types are present. In order to address some of these issues, an approach is developed where multiple hazards coalesce with losses into an index representing the risk landscape. Methods: Exposures are assessed as a proportion of land-area, allowing for multiple hazards to be combined in a single calculation. Risk calculations are weighted by land-use types (built, dual-benefit, natural) in each county. This allows for a more detailed analysis of land impacts and removes some of the bias introduced by monetary losses in heavily urbanized counties. Results: The results of the quantitative analysis show a landscape where the risk to natural systems is high and the western United States is exposed to a bulk of the risk. Land-use and temporal profiles exemplify a dynamic risk-scape. Conclusion: The calculation of risk is meant to inform community decisions based on the unique set of hazards in that area over time.

Sign in / Sign up

Export Citation Format

Share Document