River Basin
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2021 ◽  
Vol 45 ◽  
pp. 62-71
Author(s):  
Evgeny S. Koshkin ◽  
Vitaly G. Bezborodov ◽  
Aleksandr A. Kuzmin

New finds of seven East Asian Lepidoptera species in the Russian part of the southern Priamurye (Amur Basin area) are presented. Lobocla bifasciata (Bremer et Grey, 1853) (Hesperiidae), Acosmeryx naga (Moore, [1858]) and Rhagastis mongoliana (Butler, [1876]) (Sphingidae) were found in the Amur Oblast’ for the first time. Ambulyx tobii (Inoue, 1976) (Sphingidae) was first discovered in the Khabarovsk Kray; it was also found in the Chernigovsky district of the Primorsky Kray, northward from the previously known localities. New finds of very rare nemoral species, Chrysozephyrus brillantinus (Staudinger, 1887) (Lycaenidae) and Clanis undulosa Moore, 1879 (Sphingidae), in the Khabarovsk Kray are reported. It is shown that the subtropical and tropical species Siglophora sanguinolenta (Moore, 1888) (Nolidae), first collected in Russia in 2020, has successfully naturalized in the southern Khabarovsk Kray. New finds of these species indicate that the species have extended their ranges northward and naturalized in new areas. This has occurred due to climate changes in the Amur River basin over the past decades such as the rising average annual and average air temperatures during cold periods.


Atmosphere ◽  
2021 ◽  
Vol 12 (10) ◽  
pp. 1253
Author(s):  
Hongxiang Ouyang ◽  
Zhengkun Qin ◽  
Juan Li

Assimilation of high-resolution geostationary satellite data is of great value for precise precipitation prediction in regional basins. The operational geostationary satellite imager carried by the Himawari-8 satellite, Advanced Himawari Imager (AHI), has two additional water vapor channels and four other channels compared with its predecessor, MTSAT-2. However, due to the uncertainty in surface parameters, AHI surface-sensitive channels are usually not assimilated over land, except for the three water vapor channels. Previous research showed that the brightness temperature of AHI channel 16 is much more sensitive to the lower-tropospheric temperature than to surface emissivity, which is similar to the three water vapor channels 8–10. As a follow-up work, this paper evaluates the effectiveness of assimilating brightness temperature observations over land from both the three AHI water vapor channels and channel 16 to improve watershed precipitation forecasting through both case analysis (in the Haihe River basin, China) and batch tests. It is found that assimilating AHI channel 16 can improve the upstream near-surface atmospheric temperature forecast, which in turn affects the development of downstream weather systems. The precipitation forecasting test results indicate that adding the terrestrial observations of channel 16 to the assimilation of AHI data can improve short-term precipitation forecasting in the basin.


Gigabyte ◽  
2021 ◽  
Vol 2021 ◽  
pp. 1-14
Author(s):  
Alexandre Wagner Silva Hilsdorf ◽  
Marcela Uliano-Silva ◽  
Luiz Lehmann Coutinho ◽  
Horácio Montenegro ◽  
Vera Maria Fonseca Almeida-Val ◽  
...  

2021 ◽  
Author(s):  
Pragya Pradhan ◽  
Trang Thi Huyen Pham ◽  
Sangam Shrestha ◽  
Loc Ho ◽  
Edward Park

Abstract This study aims to project the compound impacts of climate change and human activities, including agriculture expansion and hydropower generation, on the future water availability in the Sre Pok River Basin. The five regional climate models (RCMs): ACESS, REMO2009, MPI, NorESM, CNRM were selected for the future climate projection under two scenarios i.e., RCP 4.5 and RCP 8.5. Our results reveal that the future annual rainfall is expected to decrease by 200 mm whereas the average temperature is expected to increase by 0.69°C to 4.16°C under future scenarios. The future water availability of Sre Pok River Basin was projected using soil and water assessment tool (SWAT). Next, the CROPWAT model was used to examine the irrigation water requirement and the HEC-ResSim model to simulate the hydropower generation of Buon Tuar Sarh reservoir. The future simulation indicates the decrease in future water availability, increasing demand for irrigation water and decreases in hydropower generation for the future periods. The irrigated areas are increases from 700 ha to 1500 ha as per the provincial development plan. This study also examines the present and future drought conditions of Sre Pok River via streamflow drought index (SDI). Our results expect to contribute toward supporting the planning and management of water resources for agriculture and to efficiently cope with drought conditions in the studied basin and beyond.


2021 ◽  
Vol 100 (5) ◽  
pp. 199-202
Author(s):  
O.G. Litovchenko ◽  
◽  
E.N. Saitova ◽  

The aim of the study is to determine the features of time and amplitude indicators of the electrocardiogram (ECG) in 7 years olds, born and living in the Northern region. Materials and methods of research: 252 7-year-old children from various educational institutions of Surgut were examined. Time and amplitude indicators of the ECG, the position of the electrical axis of the heart (EAH) were determined in 12 standard leads, the comparative analysis of the ECG indicators was carried out by gender identity. Results: all study participants had a sinus heart rate. Dysfunctions of cardiac automatism in the form of sinus tachycardia and bradycardia were found in 52,8% of 7-year-old children living in the Middle Ob river basin. A deviation of the QRS wave for more than 90 ms in 28,5% of the examined children was revealed.


2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Peter C. Nwilo ◽  
Caleb O. Ogbeta ◽  
Olagoke E. Daramola ◽  
Chukwuma J. Okolie ◽  
Michael J. Orji

Abstract Gullies and other forms of erosion have been the greatest environmental problem and catastrophe in most high- and low-income countries. The challenge posed by soil erosion has compromised agricultural productivity, environmental biodiversity and food safety for the world's population. It is important to identify vulnerable areas to soil erosion in each region to initiate remedial measures. This study demonstrates the use of watershed morphometry coupled with weighted sum analysis (WSA) to estimate the soil erosion susceptibility of the Imo River Basin sub-watersheds (SWs) in South-Eastern Nigeria using satellite remote-sensing data and geographic information system (GIS) analysis. To this end, Shuttle Radar Topography Mission (SRTM), a Digital Elevation Model (DEM) with 30 m spatial resolution was used to extract and analyse 18 morphometric parameters including basic, linear, shape and relief. The method of receiver operating characteristics (ROC) curves was used to validate the model's prediction accuracy. This morphometry-based analysis resulted in the SWs being classified into zones of low, medium, high and very high erosion susceptibility. With regard to erosion susceptibility, 41.51% of the basin (2494.68 km2) is in the very high priority zone; while 10.50%, 44.33% and 3.66% of the basin are in the high, medium and low priority zones respectively. Validation of the final erosion susceptibility map showed a prediction accuracy of 81%. The use of satellite imagery and morphometric analysis in this study was cost- and time-effective for identifying areas susceptible to soil erosion.


2021 ◽  
Vol 24 (3) ◽  
pp. 245-264
Author(s):  
Renato Pereira Lopes ◽  
Sergio Rebello Dillenburg ◽  
Jamil Corrêa Pereira ◽  
Alcides Nóbrega Sial

The Pampa in subtropical Brazil (State of Rio Grande do Sul) is the only area of South America known so far where fossils of the Pleistocene giant megatheriid sloths Megatherium americanum, characteristic of subtropical-temperate areas, and Eremotherium laurillardi, widespread in the tropical zone, were discovered in the same deposits (Pessegueiro Creek and Chuí Creek), but it is not clear whether this co-occurrence is a product of taphonomic mixture, or co-existence, which would imply niche partitioning. In order to understand their paleoecology and reconstruct the associated paleoenvironments, dentin samples of both megatheriids from the two sites were analyzed for their carbon (δ13C) and oxygen (δ18O) isotope ratios. The δ13C values of Megatherium indicate mixed diet of C3-C4 plants with higher content of the latter in Pessegueiro Creek, whereas the δ13C values of Eremotherium indicate C3-dominated diets, the more negative value in Pessegueiro Creek possibly related to the canopy effect. The δ18O of Eremotherium points to 18O-depleted water sources, possibly also influenced by the diet, whereas Megatherium ingested 18O-enriched water. The results show that co-existence of both megatheriids would have been ecologically possible, and that the Pampa was occupied by open grasslands/woodlands, with closed forests in Pessegueiro Creek. The δ13C of Eremotherium from intertropical Brazil indicate a more generalist habit than Megatherium from subtropical Brazil and Argentina, which probably facilitated its dispersion from the tropics up to subtropical areas along two different routes, one along the coastal plain, and the other along the Paraná River Basin across central South America, following the southward expansion of riparian forests during warmer stages. The reduction of those forests during intervening cold stages possibly led to its disappearance in southern Brazil. Keywords: Quaternary, paleobiogeography, stable isotopes, Pampa, coastal plain, megafauna.


Forests ◽  
2021 ◽  
Vol 12 (10) ◽  
pp. 1315
Author(s):  
Hualin Li ◽  
Jianzhong Feng ◽  
Linyan Bai ◽  
Jianjun Zhang

Quantifying the phenological variations of Populus euphratica Olivier (P. euphratica) resulting from climate change is vital for desert ecosystems. There has previously been great progress in the influence of climate change on vegetation phenology, but knowledge of the variations in P. euphratica phenology is lacking in extremely arid areas. In this study, a modified method was proposed to explore P. euphratica phenology and its response to climate change using 18-year Global Land Surface Satellite (GLASS) leaf area index (LAI) time series data (2000–2017) in the upper Tarim River basin. The start of the growing season (SOS), length of the growing season (LOS), and end of the growing season (EOS) were obtained with the dynamic threshold method from the reconstructed growth time series curve by using the Savitzky–Golay filtering method. The grey relational analysis (GRA) method was utilized to analyze the influence between the phenology and the key climatic periods and factors. Importantly, we also revealed the positive and negative effects between interannual climate factors and P. euphratica phenology using the canonical correlation analysis (CCA) method, and the interaction between the SOS in spring and EOS in autumn. The results revealed that trends of P. euphratica phenology (i.e., SOS, EOS, and LOS) were not significant during the period from 2000–2017. The spring temperature and sunshine duration (SD) controlled the SOS, and the EOS was mainly affected by the temperature and SD from June–November, although the impacts of average relative humidity (RH) and precipitation (PR) on the SOS and EOS cannot be overlooked. Global warming may lead to SOS advance and EOS delay, and the increase in SD and PR may lead to earlier SOS and later EOS. Runoff was found to be a more key factor for controlling P. euphratica phenology than PR in this region.


2021 ◽  
Vol 11 (10) ◽  
Author(s):  
Morteza Lotfirad ◽  
Arash Adib ◽  
Jaber Salehpoor ◽  
Afshin Ashrafzadeh ◽  
Ozgur Kisi

AbstractThis study evaluates the impact of climate change (CC) on runoff and hydrological drought trends in the Hablehroud river basin in central Iran. We used a daily time series of minimum temperature (Tmin), maximum temperature (Tmax), and precipitation (PCP) for the baseline period (1982–2005) analysis. For future projections, we used the output of 23 CMIP5 GCMs and two scenarios, RCP 4.5 and RCP 8.5; then, PCP, Tmin, and Tmax were projected in the future period (2025–2048). The GCMs were weighed based on the K-nearest neighbors algorithm. The results indicated a rising temperature in all months and increasing PCP in most months throughout the Hablehroud river basin's areas for the future period. The highest increase in the Tmin and Tmax in the south of the river basin under the RCP 8.5 scenario, respectively, was 1.87 °C and 1.80 °C. Furthermore, the highest reduction in the PCP was 54.88% in August under the RCP 4.5 scenario. The river flow was simulated by the IHACRES rainfall-runoff model. The annual runoff under the scenarios RCP 4.5 and RCP 8.5 declined by 11.44% and 13.13%, respectively. The basin runoff had a downward trend at the baseline period; however, it will have a downward trend in the RCP 4.5 scenario and an upward trend in the RCP 8.5 scenario for the future period. This study also analyzed drought by calculating the streamflow drought index for different time scales. Overall, the Hablehroud river basin will face short-term and medium-term hydrological drought in the future period.


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