| 1 | Relationship between niche breadth and range shifts of Rhinopoma muscatellum(Chiroptera:Rhinopomatidae)in climate change scenarios in arid and semiarid mountainous region of Iran显示文摘Rapid climate change has provided the opportunity for many species to learn to adapt fast enough to modify their range distribution.The positive and negative responses of the species in terms of distribution are related to parameters such as kind of species,degree of specialization,size and movement skills,and such factors.Moving to high elevations and transitions to higher latitudes are among the strategies proposed as a solution to the negative effects of climate change.Therefore,predicting how different species respond to climate change can help predict the conservation program for them.Species distribution models(SDMs)are widely used to predict the geographical distribution of habitat suitability and species occurrence.Rhinopoma muscatellum is one of the three mousetailed bats(Rhinopomatidae)inhabiting the southeastern,southern,and southwestern parts of Iran and its distribution range to the interior and northern parts of Iran has been limited by the Elburz and Zagros Mountain.To study the effect of climate change on this species,range shifts and coverage of protected regions,74 presence points and environmental variables(climate,topography,anthropogenic,and vegetation)in MaxEnt software were used.Before the implementation of the model,the autocorrelation of the presence points was reduced and the selection of pseudo absent points was limited by using the bias grid.Climate variables were prepared for Mid-Holocene,Current,Climate Current,and Future scenarios in 2070(RCP2.6,RCP4.5,RCP6,and RCP8.5).In order to evaluate the overlap of ecological niche,the Schoener’s D and I statistic metrics were used.Also,to measure the breadth of the niches,B1(inverse concentration)and B2(uncertainty)metrics in ENMTOOLS software were employed.TSS statistics were used as a threshold.Species distribution trend changes in climatic scenarios were performed by the Mann Kendall(MK)test.Based on the results,the AUC values for current and future climate models were calculated to be 0.89 and 0.85,respectively.The distance from settlement,soil organic carbon,and altitude variables have the greatest impact on the current distribution of the species;and among the climatic variables,Isothermality(Bio3),Temperature Seasonality(Bio4),and Max Temperature of Warmest Month(Bio5)had the greatest impact on species distribution.The results showed that in climate change scenarios by 2070,the distribution range and breadth of climatic niche of Rhinopoma muscatellum will be significantly increased(P-value<0.05),habitat fragmentation will be reduced,and in RCP8.5 scenario it will reach the maximum distribution(39.38%of total Iran).This increase will cover the Elburz and Zagros mountain ranges,and a large part of the country will be suitable for the species.In response to current climate change,migration to higher latitudes was identified in this study.Among the main different classes of protected regions in Iran(National parks,Wildlife refuges,and Protected areas),protected areas in all scenarios had the most coverage of the suitable species habitat. | Sasan KAFAEI Peyman KARAMI Robab MEHDIZADEH Vahid AKMALI | 2021 | Journal of Mountain Science2021，18，9： | 1 |
| 2 | Estimation of sediment load and erosion of different geological units: A case study from a basin of north-eastern Iran显示文摘Erosion of geological units and sediment load in rivers can be considered as the serious problems in recent decades.Increasing sediment loads generate major hazards for water resources development,particularly in terms of loss of reservoir storage due to sedimentation and siltation of water distribution systems.In this paper,the performance of four sediment rating curve (SRC) development methods was evaluated for the Shirin Darreh River(SDR) basin (1750 km^(2)),located in North Khorasan Province,Iran.Data of flow discharge (Q) and suspended sediment flux (SSF)(Q-SSF pairs,N=957)and daily flow discharge,recorded by the Regional Water Company of North Khorasan (RWCNK) at the Qaleh-Barbar (QB) gauging site during 1989-2018 were used.The flow discharge classification method performed best by meeting the desired criteria of most statistical indices,including normalized root mean square error (NRMSE),mean bias error (MBE),mean absolute error (MAE),index of agreement (d),and coefficient of determination (R^(2)).Based on the optimized method,the rate of suspended sediment transportation at the study site was estimated about2.7×10^(6) ton year^(-1).Erodibility of the exposed formations in the study area was estimated based on a factorial scoring model (FSM).Three indices,focused on the outcrop and erodibility,were calculated for the geological units at sub-basin and total scales.Marl deposits are the most extensive geological unit in the three sub-basins and the maximum formation outcrop ratio (FOR) and participation in erosion (PCE)were obtained for these rocks at total scale.In fact,marl unit can be regarded as the main source to supply the suspended sediments in the study basin. | Maryam TAJBAKHSHIAN Abolfazl MOSAEDI Mohamad Hosein MAHMUDY GHARAIE Sayyed Reza MOUSSAVI HARAMI | 2021 | Journal of Mountain Science2021，18，6： | 0 |
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