scholarly journals Landscape Characteristics Influence Ranging Behavior of Asian Elephants at The Human-Wildlands Interface in Myanmar

2021 ◽  
Author(s):  
Aung Nyein Chan ◽  
George Wittemyer ◽  
John McEvoy ◽  
Amirtharaj Christy Williams ◽  
Nick Cox ◽  
...  
Keyword(s):  
Land Use ◽  
Landscape Metrics ◽  
Spatial Configuration ◽  
Dry Season ◽  
Natural Vegetation ◽  
Range Size ◽  
Density Estimator ◽  
Ranging Behavior ◽  
Landscape Characteristics ◽  
Annual Range

Abstract ContextAsian elephant numbers are declining across much of their range driven largely by serious threats from land use change resulting in habitat loss and fragmentation. Myanmar, holding critical range for the species, is undergoing major developments due to recent sociopolitical changes. To effectively manage and conserve the remaining populations of endangered elephants in the country, it is crucial to understand their ranging behavior.ObjectivesOur objectives were to (1) estimate the sizes of dry, wet and annual ranges of free ranging elephants in Myanmar; and quantify the relationship between dry season (the period when human-elephant interactions are the most likely to occur) range size and configurations of agriculture and natural vegetation within the range, and 2) evaluate how percentage of agriculture within dry core range (50% AKDE range) of elephants relates to their daily distance traveled.MethodsWe used autocorrelated kernel density estimator (AKDE) based on a continuous-time movement modeling (ctmm) framework to estimate dry season (26 ranges from 22 different individuals), wet season (12 ranges from 10 different individuals), and annual range sizes (8 individuals), and reported the 95%, 50% AKDE, and 95% Minimum Convex Polygon (MCP) range sizes. We assessed how landscape characteristics influenced range size based on a broad array of 48 landscape metrics characterizing aspects of vegetation, water, and human features and their juxtaposition in the study areas. To identify the most relevant landscape metrics and simplify our candidate set of informative metrics, we relied on exploratory factor analysis and Spearman’s rank correlation coefficient. Based on this analysis we adopted a final set of metrics into our regression analysis. In a multiple regression framework, we developed candidate models to explain the variation in AKDE dry season range sizes based on the previously identified, salient metrics of landscape composition. ResultsElephant dry season ranges were highly variable averaging 792.0 km2 and 184.2 km2 for the 95% and 50% AKDE home ranges, respectively. We found both the shape and spatial configuration of agriculture and natural vegetation patches within an individual elephant’s range play a significant role in determining the size of its range. We also found that elephants are moving more (larger energy expenditure) in ranges with higher percentages of agricultural area.ConclusionOur results provide baseline information on elephant spatial requirements and the factors affecting them in Myanmar. This information is important for advancing future land use planning that takes into account space-use requirements for elephants. Failing to do so may further endanger already declining elephant populations in Myanmar and across the species’ range.

scholarly journals Landscape Characteristics Influence Ranging Behavior of Asian Elephants at the Human-wildlands Interface in Myanmar

2021 ◽  
Author(s):  
Aung Nyein Chan ◽  
G. Wittemyer ◽  
J. McEvoy ◽  
Amirtharaj Christy Williams ◽  
N. Cox ◽  
...  
Keyword(s):  
Land Use ◽  
Land Use Planning ◽  
Spatial Configuration ◽  
Dry Season ◽  
Natural Vegetation ◽  
Density Estimator ◽  
Ranging Behavior ◽  
Landscape Characteristics ◽  
Model Sets ◽  
Annual Range

Abstract Context Asian elephant numbers are declining across much of their range, driven largely by serious threats from land use change resulting in habitat loss and fragmentation. Myanmar, holding critical range for the species, is undergoing major developments due to recent sociopolitical changes. To effectively manage and conserve the remaining populations of endangered elephants in the country, it is crucial to understand their ranging behavior.Objectives Our objectives were to (1) quantify dry season range sizes of elephants in Myanmar and assess how they vary with different configurations of agriculture and natural vegetation; and (2) evaluate how percentage of agriculture within dry core range of elephants relates to their daily distance travelled.Methods We estimated dry season, wet season, and annual range sizes with autocorrelated kernel density estimator (AKDE) using a continuous-time movement modeling (ctmm) framework and reported the 95% and 50% AKDE and 95% Minimum Convex Polygon (MCP) range sizes. In a multiple regression framework, we developed candidate model sets to explain the variation in AKDE range sizes during the better sampled dry season when human-elephant interactions are the most likely to occur.Results Elephant dry season ranges were highly variable averaging 792 km2 and 184.2 km2 for the 95% and 50% AKDE home ranges, respectively. We found both the shape and spatial configuration of agriculture and natural vegetation patches within an individual elephant’s home range play a significant role in determining the size of its range. We also found that elephants are moving more (larger energy expenditure) in ranges with higher percentages of agricultural area.Conclusion Our results provide baseline information for advancing future land use planning that takes into account space-use requirements for elephants. Failing to do so may seriously further endangered declining elephant populations in Myanmar and across the species’ range.

scholarly journals Urban Spatial Configuration and Functional Runoff Connectivity: Influence of Drainage Grid Density and Landscape Metrics

Water ◽  
2019 ◽  
Vol 11 (12) ◽  
pp. 2661 ◽  
Author(s):  
Vincent Smets ◽  
Boud Verbeiren ◽  
Martin Hermy ◽  
Ben Somers
Keyword(s):  
Land Use ◽  
Landscape Metrics ◽  
Hydrological Modeling ◽  
Spatial Configuration ◽  
Curve Number ◽  
Strong Increase ◽  
Neutral Landscape Models ◽  
Landscape Models ◽  
Impervious Area ◽  
Cluster Area

Due to changing precipitation patterns induced by climate change, urban planners are confronted with new challenges to effectively mitigate rainfall runoff. An important knowledge gap that needs to be addressed before tackling these challenges is how and to which extent street/drainage grid density and spatial land use configuration influence the amount of runoff. Therefore, a virtual experiment was conducted to assess the influence of grid density and spatial land use configuration on the functional runoff connectivity (Fc), which is a measure of the easiness by which water flows through the landscape. Through the use of a design of experiments approach in combination with the SCS—Curve Number runoff model, a wide variety of neutral landscape models with a fixed percentage of pervious- and impervious cover were generated that maximized the variance of Fc. Correlations between landscape metrics and neutral landscape models were calculated. Our results indicated that, out of the 17 landscape metrics tested, the average impervious cluster area, the number of impervious clusters, the standard deviation of the cluster size, two proximity indexes and the effective impervious area were strongly correlated with Fc throughout all grid scenarios. The relationship between Fc on the one hand and the average impervious cluster area and the effective impervious area on the other hand, was modelled. The average impervious cluster area models showed a relationship with Fc that closely approximated a logarithmic function (R2: 0.49–0.73), while the effective impervious area models were found to have a linear relationship with Fc (R2: 0.63–0.99). A dense grid was shown to cause a strong increase in Fc, demonstrating the effectiveness of an urban grid in channeling and removing runoff. Our results further indicate that fine-grained landscapes with a lot of small impervious clusters are preferred over course-grained landscapes when the goal is to reduce Fc. In highly urbanized landscapes, where the percentage of impervious area is high, small changes in landscape pattern could significantly reduce Fc. By using a downward hydrological modeling approach this research aims to bring more clarity to the underlying variables influencing Fc, rather than trying to generate realistic prediction values.

scholarly journals Comparison of Landscape Metrics for Three Different Level Land Cover/Land Use Maps

2018 ◽  
Vol 7 (10) ◽  
pp. 408 ◽  
Author(s):  
Elif Sertel ◽  
Raziye Topaloğlu ◽  
Betül Şallı ◽  
Irmak Yay Algan ◽  
Gül Aksu
Keyword(s):  
Land Use ◽  
Land Cover ◽  
Landscape Metrics ◽  
Observation Data ◽  
Landscape Characteristics ◽  
Object Based ◽  
Level 3 ◽  
Level 1 ◽  
The Impact ◽  
Level 2

This research aims to investigate how different landscape metrics are affected by the enhancement of the thematic classes in land cover/land use (LC/LU) maps. For this aim, three different LC/LU maps based on three different levels of CORINE (Coordination of Information on The Environment) nomenclature were created for the selected study area using GEOBIA (Geographic Object Based Image Analysis) techniques. First, second and third level LC/LU maps of the study area have five, thirteen and twenty-seven hierarchical thematic classes, respectively. High-resolution Spot 7 images with 1.5 m spatial resolution were used as the main Earth Observation data to create LC/LU maps. Additional geospatial data from open sources (OpenStreetMap and Wikimapia) were also integrated to the classification in order to identify some of the 2nd and 3rd level LC/LU classes. Classification procedure was initially conducted for Level 3 classes in which we developed decision trees to be used in object-based classification. Afterwards, Level 3 classes were merged to create Level 2 LC/LU map and then Level 2 classes were merged to create the Level 1 LC/LU map according to CORINE nomenclature. The accuracy of Level 1, Level 2, Level 3 maps are calculated as; 93.50%, 89.00%, 85.50% respectively. At the last stage, several landscape metrics such as Number of Patch (NP), Edge Density (ED), Largest Patch Index (LPI), Euclidean Nearest Neighbor Distance (ENN), Splitting Index (SPLIT) and Aggregation Index (AI) metrics and others were calculated for different level LC/LU maps and landscape metrics values were compared to analyze the impact of changing thematic details on landscape metrics. Our results show that, increasing the thematic detail allows landscape characteristics to be defined more precisely and ensure comprehensive assessment of cause and effect relationships between classes.

STUDI BIONOMIK VEKTOR MALARIA DI KECAMATAN KALIBAWANG, KULONPROGO

2018 ◽  
Vol 4 (2) ◽  
Author(s):  
Sardjito Eko Windarso dkk
Keyword(s):  
Land Use ◽  
Malaria Vector ◽  
Rainy Season ◽  
Dry Season ◽  
Physical Factors ◽  
Mosquito Vector ◽  
Anopheles Species ◽  
Commercial Farming ◽  
Study Results ◽  
Dry And Rainy Seasons

The increasing of malaria cases in recent years at Kecamatan Kalibawang has been suspected correspond with the conversion of farming land-use which initiated in 1993. Four years after the natural vegetation in this area were changed become cocoa and coffee commercial farming estates, the number of malaria cases in 1997 rose more than six times, and in 2000 it reached 6085. This study were aimed to observe whether there were any differences in density and diversity of Anopheles as malaria vector between the cocoa and mix farming during dry and rainy seasons. The results of the study are useful for considering the appropriate methods, times and places for mosquito vector controlling. The study activities comprised of collecting Anopheles as well as identifying the species to determine the density and diversity of the malaria vector. Both activities were held four weeks in dry season and four weeks in rainy season. The mea-surement of physical factors such as temperature, humidity and rainfall were also conducted to support the study results. Four dusuns which meet the criteria and had the highest malaria cases were selected as study location. Descriptively, the results shows that the number of collected Anopheles in cocoa farming were higher compared with those in mix horticultural farming; and the number of Anopheles species identifi ed in cocoa farming were also more varied than those in the mix horticultural farming.Key words: bionomik vektor malaria, anopheles,

Habitat selection and range size of grass snakes Natrix natrix in an agricultural landscape in southern England

2009 ◽  
Vol 30 (3) ◽  
pp. 379-388 ◽  
Author(s):  
Christopher Reading ◽  
Gabriela Jofré
Keyword(s):  
Agricultural Landscape ◽  
Habitat Preferences ◽  
Range Size ◽  
Southern England ◽  
Natrix Natrix ◽  
Deciduous Woodland ◽  
Annual Range ◽  
Close Proximity ◽  
Habitat Boundaries ◽  
Size Estimates

AbstractThe range sizes and habitat preferences of nine adult European grass snakes (Natrix natrix) were determined from radio-tracking data obtained within a landscape of mixed deciduous woodland and pastoral fields in southern England. These data were analysed using RANGES7v0.81 software. Concave polygons resulted in overall individual range size estimates that varied between 0.18-9.41 ha. However, for individuals that were radio-tracked for more than one season, annual range size estimates ranged between 1.29 ha and 3.56 ha and some snakes shifted their range between seasons. Grass snakes showed a strong preference for habitat boundaries and interfaces and an avoidance of woodland, and fields that were used for grazing. The attributes common to habitats that snakes preferred were a combination of basking site availability and a close proximity to relatively dense vegetation that offered potential protection from predators. The attributes common to habitats that snakes avoided were a lack of basking sites in woodland, and cover, in fields. Grass snakes selected banks as hibernation sites, the majority of which were within woodland.

scholarly journals Effects of habitat structure and land-use intensity on the genetic structure of the grasshopper species Chorthippus parallelus

2014 ◽  
Vol 1 (2) ◽  
pp. 140133 ◽  
Author(s):  
Kerstin R. Wiesner ◽  
Jan Christian Habel ◽  
Martin M. Gossner ◽  
Hugh D. Loxdale ◽  
Günter Köhler ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Land Use ◽  
Genetic Structure ◽  
Sampling Site ◽  
Land Use Intensity ◽  
Habitat Size ◽  
Grasshopper Species ◽  
Chorthippus Parallelus ◽  
Landscape Characteristics ◽  
Local Populations

Land-use intensity (LUI) is assumed to impact the genetic structure of organisms. While effects of landscape structure on the genetics of local populations have frequently been analysed, potential effects of variation in LUI on the genetic diversity of local populations have mostly been neglected. In this study, we used six polymorphic microsatellites to analyse the genetic effects of variation in land use in the highly abundant grasshopper Chorthippus parallelus . We sampled a total of 610 individuals at 22 heterogeneous grassland sites in the Hainich-Dün region of Central Germany. For each of these grassland sites we assessed habitat size, LUI (combined index of mowing, grazing and fertilization), and the proportion of grassland adjoining the sampling site and the landscape heterogeneity (the latter two factors within a 500 m buffer zone surrounding each focal site). We found only marginal genetic differentiation among all local populations and no correlation between geographical and genetic distance. Habitat size, LUI and landscape characteristics had only weak effects on most of the parameters of genetic diversity of C. parallelus ; only expected heterozygosity and the grasshopper abundances were affected by interacting effects of LUI, habitat size and landscape characteristics. The lack of any strong relationships between LUI, abundance and the genetic structure might be due to large local populations of the species in the landscape, counteracting local differentiation and potential genetic drift effects.

scholarly journals Estimating population and livestock density of mobile pastoralists and sedentary settlements in the south-eastern Lake Chad area

2015 ◽  
Vol 10 (1) ◽  
Author(s):  
Vreni Jean-Richard ◽  
Lisa Crump ◽  
Abbani Alhadj Abicho ◽  
Ali Abba Abakar ◽  
Abdraman Mahamat II ◽  
...  
Keyword(s):  
Land Use ◽  
Population Density ◽  
Small Ruminants ◽  
Dry Season ◽  
Land Use Management ◽  
Lake Chad ◽  
Mobile Pastoralists ◽  
Livestock Density ◽  
Density Dynamics ◽  
First Time

Mobile pastoralists provide major contributions to the gross domestic product in Chad, but little information is available regarding their demography. The Lake Chad area population is increasing, resulting in competition for scarce land and water resources. For the first time, the density of people and animals from mobile and sedentary populations was assessed using randomly defined sampling areas. Four sampling rounds were conducted over two years in the same areas to show population density dynamics. We identified 42 villages of sedentary communities in the sampling zones; 11 (in 2010) and 16 (in 2011) mobile pastoralist camps at the beginning of the dry season and 34 (in 2011) and 30 (in 2012) camps at the end of the dry season. A mean of 64.0 people per km2 (95% confidence interval, 20.3-107.8) were estimated to live in sedentary villages. In the mobile communities, we found 5.9 people per km2 at the beginning and 17.5 people per km2 at the end of the dry season. We recorded per km2 on average 21.0 cattle and 31.6 small ruminants in the sedentary villages and 66.1 cattle and 102.5 small ruminants in the mobile communities, which amounts to a mean of 86.6 tropical livestock units during the dry season. These numbers exceed, by up to five times, the published carrying capacities for similar Sahelian zones. Our results underline the need for a new institutional framework. Improved land use management must equally consider the needs of mobile communities and sedentary populations.

scholarly journals Modeling Land Use Changes and their Impacts on Non-Point Source Pollution in a Southeast China Coastal Watershed

2018 ◽  
Vol 15 (8) ◽  
pp. 1593 ◽  
Author(s):  
Xin Zhang ◽  
Lin Zhou ◽  
Yuqi Liu
Keyword(s):  
Land Use ◽  
Point Source ◽  
River Basin ◽  
Landscape Metrics ◽  
Land Use Changes ◽  
Landscape Patterns ◽  
Cultivated Land ◽  
Point Source Pollution ◽  
Coastal Watershed ◽  
Non Point Source Pollution

Changes in landscape patterns in a river basin play a crucial role in the change on load of non-point source pollution. The spatial distribution of various land use types affects the transmission of non-point source pollutants on the basis of source-sink theory in landscape ecology. Jiulong River basin in southeast of China was selected as the study area in this paper. Aiming to analyze the correlation between changing landscape patterns and load of non-point source pollution in this area, traditional landscape metrics and the improved location-weighted landscape contrast index based on the minimum hydrological response unit (HRULCI) were applied in this study, in combination with remote sensing and geographic information system (GIS) technique. The results of the landscape metrics showed the enhanced fragmentation extent and the decreasing polymerization degree of the overall landscape in the watershed. High values of HRULCI were concentrated in cultivated land, while low HRULCI values mostly appeared in forestland, indicating that cultivated land substantially enhanced non-point source pollution, while forestland inhibited the pollution process.

scholarly journals Integrated Landscape Change Analysis of Protected Areas and their Surrounding Landscapes: Application in the Brazilian Cerrado

2020 ◽  
Vol 12 (9) ◽  
pp. 1413 ◽  
Author(s):  
Beatriz Bellón ◽  
Julien Blanco ◽  
Alta De Vos ◽  
Fabio de O. Roque ◽  
Olivier Pays ◽  
...  
Keyword(s):  
Land Use ◽  
Protected Areas ◽  
Landscape Change ◽  
Vegetation Index ◽  
Productivity Loss ◽  
Landscape Dynamics ◽  
Natural Vegetation ◽  
Local Analysis ◽  
Area Network ◽  
Conservation Areas

Remote sensing tools have been long used to monitor landscape dynamics inside and around protected areas. Hereto, scientists have largely relied on land use and land cover (LULC) data to derive indicators for monitoring these dynamics, but these metrics do not capture changes in the state of vegetation surfaces that may compromise the ecological integrity of conservation areas’ landscapes. Here, we introduce a methodology that combines LULC change estimates with three Normalized Difference Vegetation Index-based proxy indicators of vegetation productivity, phenology, and structural change. We illustrate the utility of this methodology through a regional and local analysis of the landscape dynamics in the Cerrado Biome in Brazil in 2001 and 2016. Despite relatively little natural vegetation loss inside core protected areas and their legal buffer zones, the different indicators revealed significant LULC conversions from natural vegetation to farming land, general productivity loss, homogenization of natural forests, significant agricultural expansion, and a general increase in productivity. These results suggest an overall degradation of habitats and intensification of land use in the studied conservation area network, highlighting serious conservation inefficiencies in this region and stressing the importance of integrated landscape change analyses to provide complementary indicators of ecologically-relevant dynamics in these key conservation areas.

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