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1

Assessing the suitability of habitat for wintering Siberian cranes (Leucogeranus leucogeranus) at different water levels in Poyang lake area, China

100%
Chen B., Cui P., Xu H., Lu X., Lei J., Wu Y., Shao M., Ding H., Wu J., Cao M., Liu G.
Polish Journal of Ecology
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2016
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tom 64
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nr 1
Poyang lake area (1000–3246 km²) is the most important wintering ground for the globally critically endangered Siberian crane (Leucogeranus leucogeranus). More than 98% of the Siberian crane population overwinters in Poyang lake area. Remote-sensing and the spatial analysis tools of geographic information system (GIS) technology were used to assess the suitability of the habitat for wintering Siberian cranes in Poyang lake area at different water levels. The results demonstrated that as the water level increased within the range of 7.93–12.16 m, the area of unsuitable habitat increased gradually, but the areas of good, fair and poor habitat decreased. When the water level reached 12.16 m, good habitat for Siberian cranes covered an area of only 3005 ha, which is only 0.93% of the area of the total lake area. When human disturbance factors including vehicles, fishing and construction activities were added to the analysis of the current distribution of Siberian crane habitat, the results again indicated that the area of good habitat decreased with an increase in water level within the range of 7.93–12.16 m. Additionally, the areas of good habitat occurred primarily in the region of two national nature reserves, which are the Poyang Lake National Nature Reserve and the Nanjishan National Nature Reserve. Our study provides important data and an important theoretical basis for water level management and nature reserve construction in Poyang lake area.
2

Identification of driving factors for presence of endemic species in the Aglasun district of the Mediterranean Region, Turkey

84%
Ozkan K.
Polish Journal of Ecology
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2012
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tom 60
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nr 2
This study was addressed to environmental factors significantly influencing the habitat preferences of endemic species and to obtain a model of their common habitat preferences in the Aglasun district. The district, covering an area of 55,000 hectares, is located in the lakeland subregion of the Mediterrranean region, Turkey. Data were collected from 199 sample plots (20 × 20 m ) and in total 40 endemic taxa was recorded in 124 plots which include minimum one endemic species. Wilcoxon rank-sum statistic and Pearson chisquared tests were used for continuous and categorical explanatory variables, respectively. The factors playing important roles in habitat preferences of endemic species were following: altitude, radiation index, soil texture, landscape position and landform. Generalized additive model was used for modelling the habitat preferences of endemic taxa. To obtain the best model, all significant environmental factors were evaluated by selecting stepwise option. Finally, the best model was obtained (training AUC = O.816, and crossvalidation AUC = 0.800) by using altitude and landform variables.
3

Key factors in the site selection of Rosa canina (L.) – applying the generalized additive model

84%
Guner S. T., Ozkan K., Comez A.
Polish Journal of Ecology
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2011
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tom 59
|
nr 3
Determining suitable sites for species is of great importance in the choice of plant species to be used for ecosystem restoration. The number of plant species to be used in restoration of degraded ecosystems is restricted by climate in arid and semi arid regions. Planting with economically important species in addition to ecological aspects is preferred by decision makers in Mediterrenian countries including Turkey. This study was addressed to determine the significant environmental factors influencing the distribution of dog rose hip (Rosa canina) and to obtain its distribution model. The study was carried out in an area of 26,400 km2 in The Inner Anatolia which has semiarid climate. 106 sample plots, 20 x 20 m in size, were selected from different sites with and without Rosa canina in the summer of 2007. Wilcoxon rank-sum statistic for continuous variables and Pearson Chi-square tests for categorical variables were applied. Altitude, slope degree, available water capacity, soil reaction and soil K, Ca, Mg content as well and total calcium carbonate amount as the continuous variables and northwest- northeast group of aspect, metamorphic group of bedrock as the categorical variables were determined as the significant factors influencing the presence of dog rose. Generalized Additive Model (GAM) was performed for modeling the distribution of the species. To obtain the best model, all significant environmental factors were evaluated. The best model result was obtained (training Area Under Curve (AUC) = 0.902 and cross-validation AUC = 0.841) by means of altitude, slope degree, aspect, and bedrock. Interspecific correlation analysis (ICA) was applied to define indicator species accompanying the dog rose. Dog rose distribution was positively correlated with Cistus laurifolius, Pyrus elaeagnifolia, Lonicera caucasica subsp. orientalis, Quercus vulcanica and Amelanchier rotundifolia subsp. Rotundifolia. The results obtained from this study are crucial for estimation of the suitable areas for Dog rose in restoration studies of natural ecosystems in the Mediterranean region, including Anatolia in Turkey.
4

The impact of climate change on habitat suitability for Artemisia sieberi and Artemisia aucheri (Asteraceae) – a modeling approach

84%
Mousaei Sanjerehei M., Rundel P. W.
Polish Journal of Ecology
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2017
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tom 65
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nr 1
We determined the current potential distribution of Artemisia sieberi and A. aucheri, two important widespread rangeland shrub species in Iran, using bioclimatic variables with and without the addition of elevation (E) to the MaxEnt model. The impact of climate change on the habitat suitability of the Artemisiaspecies was modeled for mid century under the projected climate change of GFDL-ESM2G (RCP2.6) model, a warmer and slightly wetter condition, and CCSM4 (RCP4.5) model, a warmer and drier condition. The results showed that annual precipitation (AP) and temperature annual range (TAR) were the most important drivers of A. aucheri distribution at a regional scale. With the addition of E to the model, we found that E and AP were the most significant factors in determining the habitat suitability of this species. The most significant factors influencing A. sieberi distribution were AP and annual mean temperature (AMT). E was not identified as the important variable influencing A. sieberi distribution when was added to the model in spite of its high correlation to AMT (|r| > 0.8), while AP was the most important, indicating that A. sieberi is less dependent on elevation than A. aucheri. A. aucheri is regarded as a high elevation species (E > 2500 m) which can be distributed in colder and wetter areas as compared to A. sieberi, a mid-elevation species (E < 2500 m). The projected climate change using both models has a much more impact on A. aucheri, potentially driving more losses and fewer gains in climatically suitable habitat of this species as compared to A. sieberi suggesting the adaptation of the later to a wider range of climatic conditions than A. aucheri. The results of the current and future distribution modeling of the Artemisia species is significant in managing susceptible habitats of these species for climate change and for habitat restoration.
5

Habitat suitability, corridors and dispersal barriers for large carnivores in Poland

84%
Huck M., Jedrzejewski W., Borowik T., Milosz-Cielma M., Schmidt K., Jedrzejewska B., Nowak S., Myslajek R. W.
Acta Theriologica
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2010
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tom 55
|
nr 2
177-192
Carnivores are often particularly sensitive to landscape fragmentation. Ecological corridors may help to connect local populations, ensuring gene flow and retaining viable meta-populations. We aimed to establish habitat suitability models for two large carnivores in Poland, the grey wolf Canis lupus Linnaeus, 1758 and the Eurasian lynx Lynx lynx Linnaeus, 1758, based on ecological niche factor analysis (ENFA). Secondly, we calculated least cost paths (LCPs) based on cost values obtained from ENFA. Thirdly, we determined structures that might act as barriers, thus diminishing the value of the corridor unless appropriate conservation measures are taken. We compared some of the results with actual dispersal data of four lynx in eastern Poland. Results indicate that both species are highly marginalised. Less habitat that is currently available in Poland is suitable for lynx than for wolves. We determined a total of 76 LCPs. Comparison of these theoretical corridors with actual dispersal routes suggests that the traits of calculated LCPs are mostly within the range of those of real routes. We highlight a variety of features that might act as barriers, such as major roads (including planned highways), urbanized areas, and large un-forested areas. We give suggestions where concerted conservation efforts (eg wildlife passages) might be particularly well-directed.
6

Land use and land cover change in protected areas: using remote sensing to survey suitable habitats of brown bear Ursus arctos

84%
Farashi A., Parvian N., Najafabadi M. S.
Polish Journal of Ecology
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2016
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tom 64
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nr 3
In recent years, brown bear Ursus arctos populations in Iran have experienced a clear trend of reduction and the species is now officially listed as threatened under provincial legislation. Anthropogenic habitat alteration and increasing human access to previously remote landscapes are potential source of stress for this species in Iran. Therefore, land cover changes in the Chelcheli protected area were mapped for 1991–2013 using time sequential Landsat TM and ETM at 30 meters resolution. Moreover, Maximum entropy (MaxEnt) modeling was used to investigate habitat selection of brown bear. The results showed that suitable patches overlapped with forest areas (Hyrcanian forest) and rivers. Our results also indicate that the brown bear habitat suitability is negatively influenced by human disturbance (e.g., roads, settlements). Increased human disturbance in brown bear habitat in recent decades may cause bears to avoid the disturbed areas. Therefore, the management plans should focus on reducing the human infrastructures around brown bear habitat. A suggestion is to place the core secure areas for brown bear inside the suitable habitat close to rivers where the human access is restricted. Promoting awareness of biodiversity conservation among tourism should also be one of the major focuses of management plans.
7

Analyses of least cost paths for determining effects of habitat types on landscape permeability: wolves in Poland

84%
Huck M., Jedrzejewski W., Borowik T., Jedrzejewska B., Nowak S., Myslajek R. W.
Acta Theriologica
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2011
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tom 56
|
nr 1
Determining ecological corridors is crucial for conservation efforts in fragmented habitats. Commonly employed least cost path (LCP) analysis relies on the underlying cost matrix. By using Ecological Niche Factor Analysis, we minimized the problems connected with subjective cost assessment or the use of presence/absence data. We used data on the wolf presence/absence in Poland to identify LCPs connecting patches of suitable wolf habitat, factors that influence patch occupancy, and compare LCPs between different genetic subpopulations. We found that a lower proportion of cities and roads surrounds the most densely populated patches. Least cost paths between areas where little dispersal takes place (i.e., leading to unpopulated patches or between different genetic subpopulations) ran through a higher proportion of roads and human settlements. They also crossed larger maximal distances over deforested areas. We propose that, apart from supplying the basis for direct conservation efforts, LCPs can be used to determine what factors might facilitate or hinder dispersal by comparing different subsets of LCPs. The methods employed can be widely applicable to gain more in-depth information on potential dispersal barriers for large carnivores.
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