scholarly journals Predicting the Distribution of Oxytropis ochrocephala Bunge in the Source Region of the Yellow River (China) Based on UAV Sampling Data and Species Distribution Model

2021 ◽  
Vol 13 (24) ◽  
pp. 5129
Author(s):  
Xinyu Zhang ◽  
Yaxin Yuan ◽  
Zequn Zhu ◽  
Qingshan Ma ◽  
Hongyan Yu ◽  
...  
Keyword(s):  
Species Distribution ◽  
Yellow River ◽  
Source Region ◽  
Regional Scale ◽  
Animal Husbandry ◽  
Aerial Photographs ◽  
Distribution Model ◽  
Suitable Habitat ◽  
Observation Data ◽  
Distribution Ranges

Oxytropis ochrocephala Bunge is an herbaceous perennial poisonous weed. It severely affects the production of local animal husbandry and ecosystem stability in the source region of Yellow River (SRYR), China. To date, however, the spatiotemporal distribution of O. ochrocephala is still unclear, mainly due to lack of high-precision observation data and effective methods at a regional scale. In this study, an efficient sampling method, based on unmanned aerial vehicle (UAV), was proposed to supply basic sampling data for species distribution models (SDMs, BIOMOD in this study). A total of 3232 aerial photographs were obtained, from 2018 to 2020, in SRYR, and the potential and future distribution of O. ochrocephala were predicted by an ensemble model, consisting of six basic models of BIOMOD. The results showed that: (1) O. ochrocephala mainly distributed in the southwest, middle, and northeast of the SRYR, and the high suitable habitat of O. ochrocephala accounted for 3.19%; (2) annual precipitation and annual mean temperature were the two most important factors that affect the distribution of O. ochrocephala, with a cumulative importance of 60.45%; and (3) the distribution probability of O. ochrocephala tends to increase from now to the 2070s, while spatial distribution ranges will remain in the southwest, middle, and northeast of the SRYR. This study shows that UAVs can potentially be used to obtain the basic data for species distribution modeling; the results are both beneficial to establishing reasonable management practices and animal husbandry in alpine grassland systems.

scholarly journals Protected areas’ effectiveness under climate change: a latitudinal distribution projection of an endangered mountain ungulate along the Andes Range

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e5222 ◽  
Author(s):  
Carlos Riquelme ◽  
Sergio A. Estay ◽  
Rodrigo López ◽  
Hernán Pastore ◽  
Mauricio Soto-Gamboa ◽  
...  
Keyword(s):  
Climate Change ◽  
Protected Areas ◽  
Species Distribution ◽  
Climate Models ◽  
Species Distribution Model ◽  
Global Climate Models ◽  
Distribution Model ◽  
Suitable Habitat ◽  
Climate Change Scenarios ◽  
Distribution Ranges

BackgroundClimate change is one of the greatest threats to biodiversity, pushing species to shift their distribution ranges and making existing protected areas inadequate. Estimating species distribution and potential modifications under climate change are then necessary for adjusting conservation and management plans; this is especially true for endangered species. An example of this issue is the huemul (Hippocamelus bisulcus), an endemic endangered deer from the southern Andes Range, with less than 2,000 individuals. It is distributed in fragmented populations along a 2,000 km latitudinal gradient, in Chile and Argentina. Several threats have reduced its distribution to <50% of its former range.MethodsTo estimate its potential distribution and protected areas effectiveness, we constructed a species distribution model using 2,813 huemul presence points throughout its whole distribution range, together with 19 bioclimatic layers and altitude information from Worldclim. Its current distribution was projected for years 2050 and 2070 using five different Global Climate Models estimated for scenarios representing two carbon Representative Concentration Routes (RCP)—RCP4.5 and RCP6.0.ResultsBased on current huemul habitat variables, we estimated 91,617 km2of suitable habitat. In future scenarios of climate change, there was a loss of suitable habitat due to altitudinal and latitudinal variation. Future projections showed a decrease of 59.86–60.26% for the year 2050 and 58.57–64.34% for the year 2070 according to RCP4.5 and RCP6.0, respectively. Protected areas only covered only 36.18% of the present distribution, 38.57–34.94% for the year 2050 and 30.79–31.94% for 2070 under climate change scenarios.DiscussionModeling current and future huemul distributions should allow the establishment of priority conservation areas in which to focus efforts and funds, especially areas without official protection. In this way, we can improve management in areas heavily affected by climate change to help ensure the persistence of this deer and other species under similar circumstances worldwide.

Soft rock cliff retreat under changing climate drivers

2020 ◽  
Author(s):  
Thomas Spencer ◽  
Susan Brooks
Keyword(s):  
North Sea ◽  
Regional Scale ◽  
Soft Rock ◽  
Water Levels ◽  
Sediment Supply ◽  
Aerial Photographs ◽  
Observation Data ◽  
Short Term ◽  
Sediment Release ◽  
Cliff Retreat

&lt;p&gt;Shoreline retreat can happen rapidly in cliffs composed of loosely consolidated glacial and pre-glacial sediments. Typical centennial-scale average retreat rates for some cliffed coastlines of East Anglia, UK are 2 - 5 m a&lt;sup&gt;-1&lt;/sup&gt; where cliffs have no protection from storm energetics. Recent research using pre- and post-storm clifftop (geomorphological) surveys, as well as aerial photographs, has shown that in single events retreat can be 3 &amp;#8211; 4 times the long-term average, with up to 15 m of retreat in a single event. Periods of clifftop stasis are thus interspersed with short term shocks, when meteorological conditions generate energetic drivers of change (elevated still water levels, high onshore waves, high rainfall inputs). Furthermore, short term shocks deliver enhanced sediment supply to the nearshore region, which is an important factor to take into account within future management planning strategies. &amp;#160;&lt;/p&gt;&lt;p&gt;This paper uses the latest Earth Observation data to quantify and evaluate rates of soft rock cliff retreat, thereby identifying periods when short term shocks have been delivered to the cliffs. It then explores the climate drivers of these shocks and assesses the associated synoptic meteorological scenarios. Finally it considers the implications for quantities of sediment released, in terms of both overall magnitude and alongshore variability.&lt;/p&gt;&lt;p&gt;Results suggest that three recent events stand out as having a significant impact on rates of cliff retreat and associated sediment release on the Suffolk coast, southern North Sea. The &amp;#8220;Big Freeze&amp;#8221; of the UK winter of 2010-11 involved a protracted period of easterly air flow from mid-November and into December, 2010. The process drivers were high magnitude onshore winds, generating nearshore waves of around 4 m. The 5 December 2013 North Sea surge similarly resulted in rapid cliff retreat and sediment release. In this event winds were alongshore so the wave impacts were lower, but the elevated water levels generated by the surge meant that wave action could be directed onto the cliffs. By far the biggest recent event in terms of storm forcing energetics was the February &amp;#8211; March 2018 &amp;#8220;Beast from the East&amp;#8221; and &amp;#8220;Mini Beast&amp;#8221;, where persistent onshore winds generated waves of almost 4.5 m at Southwold Approaches (highest on record) that coincided with two phases of high spring tides (no surge). When regional-scale Sudden Stratospheric Warming (SSW) generates strong and persistent easterly winds there are widespread potentially irreversible consequences for cliff and beach sediments around the western North Sea coastline.&lt;/p&gt;

Species Distribution Models (SDM) – A Strategic Tool for Predicting Suitable Habitats for Conserving the Target Species

2017 ◽  
pp. 427-440
Author(s):  
Balaguru Balakrishnan ◽  
Nagamurugan Nandakumar ◽  
Soosairaj Sebastin ◽  
Khaleel Ahamed Abdul Kareem
Keyword(s):  
Species Distribution ◽  
Spatial Data ◽  
Environmental Variables ◽  
Species Distribution Models ◽  
Species Distribution Model ◽  
Distribution Model ◽  
Suitable Habitat ◽  
Target Species ◽  
Distribution Models ◽  
Suitable Habitats

Conservation of the species in their native landscapes required understanding patterns of spatial distribution of species and their ecological connectivity through Species Distribution Models (SDM) by generation and integration of spatial data from different sources using Geographical Information System (GIS) tools. SDM is an ecological/spatial model which combines datasets and maps of occurrence of target species and their geographical and environmental variables by linking various algorithms together, that has been applied to either identify or predict the regions fulfilling the set conditions. This article is focused on comprehensive review of spatial data requirements, statistical algorithms and softwares used to generate the SDMs. This chapter also includes a case study predicting the suitable habitat distribution of Gnetum ula, an endemic and vulnerable plant species using maximum entropy (MaxEnt) species distribution model for species occurrences with inputs from environmental variables such as bioclimate and elevation.

Spatial simulation of water supply service flow in Ningxia, China

2020 ◽  
Author(s):  
Jie Xu ◽  
Gaodi Xie ◽  
Yu Xiao ◽  
Jingya Liu ◽  
Keyu Qin ◽  
...  
Keyword(s):  
Water Supply ◽  
River Basin ◽  
Water Conservation ◽  
Arid Regions ◽  
Yellow River ◽  
Source Region ◽  
Regional Scale ◽  
Tibet Plateau ◽  
Residual Water ◽  
Semi Arid

&lt;p&gt;Transregional Ecosystem Service (ES) flows are ubiquitous and are receiving more attention in an increasingly metacoupled world. Water has typical flow properties and is a common flow medium of Water-related Ecosystem Services (WES), such as water supply, water conservation, etc. Ningxia is in a transition zone from semi-arid to arid areas of the Yellow River basin of China. Its role in the water transfer from the Qinghai-Tibet Plateau to the downstream city and agriculture is important in allocating the scarce water resources in (semi-)arid regions. This study described the water flow process to/from Ningxia and revealed the supply-demand balance of water in Ningxia and its adjacent basins. On the grid scale, the total dynamic residual water in Ningxia from 2000 to 2015 was 2.20&amp;#215;10&lt;sup&gt;12&lt;/sup&gt; m&lt;sup&gt;3&lt;/sup&gt;~6.26&amp;#215;10&lt;sup&gt;12&lt;/sup&gt; m&lt;sup&gt;3&lt;/sup&gt;. However, there was still a dynamic water demand gap of -72.25&amp;#215;10&lt;sup&gt;8&lt;/sup&gt; m&lt;sup&gt;3&lt;/sup&gt; ~ -59.08&amp;#215;10&lt;sup&gt;8&lt;/sup&gt; m&lt;sup&gt;3&lt;/sup&gt;, which could only be supplemented by manual water intake. At the regional scale, Ningxia had two sides, which was both the beneficiary of the upper Xiaheyan basin, Qingshui River - Kushui River basin, Xiaheyan - Shizuishan basin, Hexi Inland River-Shiyang River basin, Hexi Inland Rive-Hexi desert basin and internal flow area, and the supplier of the downstream Shizuishan - Hekou town, Longmen to Sanmenxia subbasin. As the benefitting district, the total net inflow water supply service in the supply area from 2000 to 2015 was 135.86&amp;#215;10&lt;sup&gt;8&lt;/sup&gt; m&lt;sup&gt;3 &lt;/sup&gt;~ 294.22&amp;#215;10&lt;sup&gt;8&lt;/sup&gt; m&lt;sup&gt;3&lt;/sup&gt;, among which the non-Ningxia region in the sub-basin above the Xiaheyan basin was the main source region of water supply service in Ningxia. As the supply area, the net outflow volume of water supply service in Ningxia from 2000 to 2015 was 72.83&amp;#215;10&lt;sup&gt;8&lt;/sup&gt; m&lt;sup&gt;3&lt;/sup&gt;~200.46&amp;#215;10&lt;sup&gt;8&lt;/sup&gt; m&lt;sup&gt;3&lt;/sup&gt;, mainly flowing to non-Ningxia regions from Shizuishan to Hekou town. Overall, the net volume of water supply service flowing into Ningxia from 2000 to 2015 ranged from 63.03&amp;#215;10&lt;sup&gt;8&lt;/sup&gt; m&lt;sup&gt;3&lt;/sup&gt; to 93.76&amp;#215;10&lt;sup&gt;8&lt;/sup&gt; m&lt;sup&gt;3&lt;/sup&gt;. This study can enhance the understanding of trans-boundary telecoupling relationship of WES in Ningxia and contribute to form a foundation for interregional management and allocation of WES in (semi-)arid regions to promote equity in sustainable regional development.&lt;/p&gt;

scholarly journals Predicting the Current and Future Suitable Habitat Distribution of Swimming Crab (Portunus trituberculatus) using the Species Distribution Model under Climate Change

2021 ◽  
Author(s):  
Xinyu Liu ◽  
Xiaolu Han ◽  
Zhiqiang Han
Keyword(s):  
Climate Change ◽  
Species Distribution ◽  
Species Distribution Model ◽  
Seawater Temperature ◽  
The Yellow Sea ◽  
Distribution Model ◽  
Portunus Trituberculatus ◽  
Suitable Habitat ◽  
Different Seasons ◽  
Rcp 8.5

Species have shown their habital variations in responding to climate change, especially during the spring and summer spawning seasons. The species distribution model (SDM) is considered the most favorable tool to study the potential effects of climate change on species distribution. Therefore, we developed the ensemble SDM to predict the changes in species distribution of Portunus trituberculatus among different seasons in 2050 and 2100 under the climate scenarios RCP4.5 and RCP8.5. The results of SDM indicate that the distribution of this species will move northward and have obviouse seasonal variations. Meanwhile, the suitable habitat for the species will be significantly reduced in summer, with loses rates ranging from 45.23% (RCP4.5) to 88.26% (RCP.8.5) by 2100s. Habitat reduction will mainly occur in the East China Sea and southern part of the Yellow Sea, while there will be a small increase in the northern Bohai Sea. These findings will be important to manage the ecosystem and fishery, provide an information forecast of this species in the future, and maintain species diversity if the seawater temperature rises.

scholarly journals Better providers of habitat for Javan slow loris (Nycticebus javanicus E. Geoffroy 1812): A species distribution modeling approach in Central Java, Indonesia

2020 ◽  
Vol 21 (5) ◽  
Author(s):  
Mahfut Sodik ◽  
Satyawan Pudyatmoko ◽  
Pujo Semedi Hargo Yuwono ◽  
Muhammad Tafrichan ◽  
Muhammad Ali Imron
Keyword(s):  
Species Distribution ◽  
Species Distribution Modeling ◽  
Distribution Model ◽  
Suitable Habitat ◽  
Conservation Areas ◽  
Slow Loris ◽  
Modeling Approach ◽  
Central Java ◽  
Distribution Modeling ◽  
Central Java Province

Abstract. Sodik M, Pudyatmoko S, Yuwono PSH, Tafrichan M, Imron MA. 2020. Better providers of habitat for Javan slow loris (Nycticebus javanicus E. Geoffroy 1812): A species distribution modeling approach in Central Java, Indonesia. Biodiversitas 21: 1890-1900. The Javan slow loris is an arboreal and nocturnal primate endemic to Java, which is known to inhabit primary and secondary forest habitats, such as swamps, plantations, and bamboo forest. The population of the Javan slow loris continues to decline significantly due to forest degradation, habitat loss/fragmentation, and illegal trade. Conservation of this small primate in Java has been hampered by a paucity of local data on how conservation areas support this species. This study aims to build a spatial distribution model of the Javan slow loris and analyzing the role of each stakeholder plays on land use type to support the conservation of N. javanicus. By utilizing Species Distribution Modeling (SDM) with Maximum Entropy species distribution modeling approach, the researchers were able to highlight the importance of which conservation areas in Central Java that play crucial role to conserve the N. javanicus population. Data on the presence of the Javan slow loris was obtained from the result of a survey undertaken in 2017 and communication with researchers. Elevation, slope, landcover, rainfall, distance to road, distance to settlement, distance to river (water source), and NDVI were used as environmental variables. Results showed that 0.76% (25,715.4 ha) of the total area of the Central Java Province is suitable for their habitat. In addition, results revealed that 2.2% of suitable habitat is present within conservation areas, 4.6% in protected forest areas, and 93.2% outside of protected areas. The Javan slow loris is predicted to be mostly scattered in the northern part of Central Java Province. The Javan slow loris is widely distributed in plantations, their most dominant habitat. The findings of this study show that the small percentage of suitable habitat presents within protected forest and conservation areas cannot sustainably maintain the extant Javan slow loris population. Thus, it is important for the Indonesian government and other key related stakeholders to work together in combination with educating local communities to preserve the habitat and population of N. javanicus.

scholarly journals Defining Conservation Requirements for the Suweon Treefrog (Dryophytes suweonensis) Using Species Distribution Models

Diversity ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 69
Author(s):  
Il-Kook Park ◽  
Daesik Park ◽  
Amaël Borzée
Keyword(s):  
Habitat Loss ◽  
Species Distribution ◽  
Species Distribution Model ◽  
Rice Paddy ◽  
Habitat Characteristics ◽  
Distribution Model ◽  
Suitable Habitat ◽  
Rice Paddies ◽  
Agricultural Wetlands ◽  
North East

Numerous amphibian species are declining because of habitat loss and fragmentation due to urbanization of landscapes and the construction of roads. This is a mounting threat to species restricted to habitats close to urban areas, such as agricultural wetlands in North East Asia. The Suweon treefrog (Dryophytes suweonensis) falls into the list of species threatened with habitat loss and most populations are under threat of extirpation. Over the last decades, sub-populations have become increasingly disconnected and specifically the density of paved roads has increased around the only site connecting northern and southern Seoul populations. We surveyed this locality in Hojobeol, Siheung, Republic of Korea in 2012, 2015 and 2019 to first confirm the decline in the number of sites where D. suweonensis was present. The second objective was to analyze the habitat characteristics and determine the remaining suitable habitat for D. suweonensis through a species distribution model following the maximum entropy method. Our results show that rice paddy cover and distance from the paved road are the most important factor defining suitable habitat for D. suweonensis. At this locality, uninterrupted rice paddies are a suitable habitat for the species when reaching at least 0.19 km2, with an average distance of 138 ± 93 m2 from the roads. We link the decrease in the number of sites where D. suweonensis is present with the decrease in rice paddy cover, generally replaced by localized infrastructures, greenhouses and habitat fragmentation. Rice paddies should remain connected over a large area for the protection of the remaining populations. In addition, habitat requirements should be integrated in the requisites to designate protected areas.

scholarly journals Undetected but widespread: the cryptic invasion of non-native cattail (Typha spp.) in a Pacific Northwest estuary

2021 ◽  
Author(s):  
Daniel James Stewart ◽  
W. Gregory Hood ◽  
Tara G. Martin
Keyword(s):  
Cultural Values ◽  
Pacific Northwest ◽  
Species Distribution ◽  
Species Distribution Model ◽  
River Estuary ◽  
Typha Latifolia ◽  
Tidal Marshes ◽  
Distribution Model ◽  
Suitable Habitat ◽  
Hybrid Cattail

Abstract Early detection of invasive species is an important predictor of management success. Non-native narrow-leaved cattail (Typha angustifolia) has been detected in the Fraser River Estuary (FRE) in recent decades, but questions around their degree of establishment, and the potential emergence of hybrid cattail (Typha x glauca), remain unanswered. This study models the current and potential future distribution of non-native cattails in the FRE using a unique combination of spectral imagery analysis and species distribution modelling. Contrary to our expectation, we find that non-native cattails are already widespread, currently occupying approximately 4% of FRE tidal marshes. Though never formally recorded in the FRE, hybrid cattail is the more abundant of the two taxa, suggesting that heterosis may be facilitating this invasion. In our species distribution model, we distinguish between site suitability (ability to establish and persist) and site susceptibility (risk of being colonized when suitable). Our model predicts that 28% of the estuary has > 50% probability of suitability, and 21% has > 50% probability of susceptibility to non-native Typha, indicating the scale of this invasion may increase over time. Restoration projects had proportionally more cattail, susceptible habitat, and suitable habitat than the overall estuary, casting doubt on their effectiveness at mitigating wetland destruction. Due to their resemblance to native Typha latifolia, these cattails qualify as cryptic invaders, which explains how they were able to establish and remain undetected for decades. Regional eradication is unlikely given the extent of invasion, therefore management should prioritize areas of high conservation and cultural values.

scholarly journals Comprehensive Research on Remote Sensing Monitoring of Grassland Degradation: A Case Study in the Three-River Source Region, China

2019 ◽  
Vol 11 (7) ◽  
pp. 1845 ◽  
Author(s):  
Ying Zhang ◽  
Chaobin Zhang ◽  
Zhaoqi Wang ◽  
Ru An ◽  
Jianlong Li
Keyword(s):  
Remote Sensing ◽  
Net Primary Productivity ◽  
Comprehensive Evaluation ◽  
Yellow River ◽  
Source Region ◽  
Regional Scale ◽  
Vegetation Coverage ◽  
Grassland Degradation ◽  
Annual Change ◽  
Remote Sensing Monitoring

In this study, we proposed climate use efficiency (CUE), a new index in monitoring grassland ecosystem function, to mitigate the disturbance of climate fluctuation. A comprehensive evaluation index (EI), combining with actual vegetation net primary productivity (NPP), CUE, vegetation coverage, and surface bareness, was constructed for the dynamic remote sensing monitoring of grassland degradation/restoration on a regional scale. By using this index, the grassland degradation/restoration in the Three-River Source Region (TRSR) was quantitatively evaluated during 2001–2016, which has been an important ecological barrier area in China. Results showed the following: During the study period, the grassland of Yellow River source (SRYe) had high vegetation coverage, NPP, CUE, and low bareness, whereas Yangtze River source (SRYa) had low vegetation coverage, NPP, CUE, and high bareness. The vegetation coverage and CUE of the grassland showed upward trends, with annual change rates of 0.75% and 0.45% year −1. The surface bareness and NPP showed downward trends, with annual change rates of −0.37% year−1 and −0.24 g C m−2 yr−2, respectively. Assessment of EI revealed that 67.18% of the grassland of TRSR showed a recovery trend during the study period. The overall restoration of the SRYe was the best, followed by SRYa. However, the status of Lancang River source (SRLa) was poor.

scholarly journals Quantification of land-sea nutrient fluxes supplied by allis shad across the species' range

2021 ◽  
Author(s):  
Camille Poulet ◽  
Betsy L. Barber-O'Malley ◽  
Géraldine Lassalle ◽  
Patrick Lambert
Keyword(s):  
Ecosystem Services ◽  
Species Distribution ◽  
Large Scale ◽  
Western Europe ◽  
Species Distribution Model ◽  
Distribution Model ◽  
Nutrient Loads ◽  
Allis Shad ◽  
Distribution Ranges ◽  
Nutrient Subsidies

Diadromous species act as nutrient vectors between their marine and freshwater habitats. Few valuations of this regulating service exist and none at the scale of species distribution ranges. This large-scale approach seems particularly relevant for species moving and exchanging individuals across borders and territories as these populations may strongly depend upon each other in terms of population viability and provision of ecosystem services. The development of a new nutrient routine within an existing mechanistic species distribution model provided estimates of the 'maximum potential' of the anadromous allis shad (Alosa alosa) to provide nitrogen and phosphorous subsidies throughout Western Europe. During their seasonal reproductive migration, shad provided low amounts of nutrient subsidies when compared to North-American anadromous species and annual riverine nutrient loads. However, these subsidies are delivered as pulses concentrated in space and time, suggesting that more work is needed to figure out the significance of these shad-derived nutrients in terms of riverine ecosystem functioning. The evidence of a substantial flow of strayers delivering nutrient subsidies in several rivers confirmed the need for large-scale management of migratory species to ensure a sustainable provision of ecosystem services.

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