scholarly journals Analysis of the Characteristics of Climate Change in the Ecologically Vulnerable Area of the Mu Us Dune Field under the Background of Global Warming

2021 ◽  
Vol 13 (4) ◽  
pp. 627
Author(s):  
Guanwen Huang ◽  
Hai Zhu ◽  
Juqing Zhang ◽  
Bohan Liu
Keyword(s):  
Spatial Distribution ◽  
Environmental Changes ◽  
Average Rate ◽  
Precipitable Water ◽  
Research Field ◽  
Average Level ◽  
Vegetation Coverage ◽  
Dune Field ◽  
Rate Of Increase ◽  
Surrounding Areas

The Mu Us dune field is one of China’s four major dune fields, which are ecologically vulnerable areas of northwest semiarid land across Shaanxi, Ningxia, and Inner Mongolia, also very sensitive to the global temperature rise and environmental changes. This paper uses data on the temperature, precipitation, and precipitable water vapor (PWV) in the Mu Us dune field and its surrounding areas to analyze and discuss the time series and spatial distribution characteristics of these three factors in this area. The results of the study show that, in recent years, the trend of temperature increase in the Mu Us dune field has been higher than the average level in China, but this trend has gradually subsided since 2000. The spatial distribution of temperature presents an obvious characteristic of gradual increase from north to south and is affected by latitude, altitude, and topography. The annual cumulative precipitation of the Mu Us dune field is lower than the average level in China. However, in recent years, the rate of the increase in precipitation in this area has been significantly higher than that of the average rate of increase in China. The eastern part of the dune field has the most precipitation, which gradually decreases to the west. The spatial distribution of precipitation is greatly affected by monsoon factors in the region and the distribution of rivers. In the research field, PWV has been rising in recent years, which is greatly related to the increase of vegetation coverage in this region. This demonstrates that the Mu Us dune field has experienced a “warmer and wetter” trend in recent years.

Lake and inland dunes as interconnected Systems: The story of Lake Tresssee and an adjacent dune field (Schleswig-Holstein, North Germany)

The Holocene ◽  
2020 ◽  
pp. 095968362098168
Author(s):  
Christian Stolz ◽  
Magdalena Suchora ◽  
Irena A Pidek ◽  
Alexander Fülling
Keyword(s):  
Water Level ◽  
Bronze Age ◽  
Environmental Changes ◽  
High Water ◽  
Alluvial Fan ◽  
Water Levels ◽  
Lake Area ◽  
Dune Field ◽  
The North ◽  
Sand Drift

The specific aim of the study was to investigate how four adjacent geomorphological systems – a lake, a dune field, a small alluvial fan and a slope system – responded to the same impacts. Lake Tresssee is a shallow lake in the North of Germany (Schleswig-Holstein). During the Holocene, the lake’s water surface declined drastically, predominately as a consequence of human impact. The adjacent inland dune field shows several traces of former sand drift events. Using 30 new radiocarbon ages and the results of 16 OSL samples, this study aims to create a new timeline tracing the interaction between lake and dunes, as well, as how both the lake and the dunes reacted to environmental changes. The water level of the lake is presumed to have peaked during the period before the Younger Dryas (YD; start at 10.73 ka BC). After the Boreal period (OSL age 8050 ± 690 BC) the level must have undergone fluctuations triggered by climatic events and the first human influences. The last demonstrable high water level was during the Late Bronze Age (1003–844 cal. BC). The first to the 9th century AD saw slightly shrinking water levels, and more significant ones thereafter. In the 19th century, the lake area was artificially reduced to a minimum by the human population. In the dunes, a total of seven different phases of sand drift were demonstrated for the last 13,000 years. It is one of the most precisely dated inland-dune chronologies of Central Europe. The small alluvial fan took shape mainly between the 13th and 17th centuries AD. After 1700 cal. BC (Middle Bronze Age), and again during the sixth and seventh centuries AD, we find enhanced slope activity with the formation of Holocene colluvia.

scholarly journals Development and Assessment of a New Framework for Agricultural Nonpoint Source Pollution Control

Water ◽  
2021 ◽  
Vol 13 (22) ◽  
pp. 3156
Author(s):  
Lili Zhou ◽  
Runzhe Geng
Keyword(s):  
Spatial Distribution ◽  
Large Scale ◽  
Factor Model ◽  
Five Factor Model ◽  
Pollution Source ◽  
Nonpoint Source ◽  
Vegetation Coverage ◽  
Buffer Strip ◽  
Rural Living ◽  
Agricultural Nonpoint Source

The transport of agricultural nonpoint source (NPS) pollutants in water pathways is affected by various factors such as precipitation, terrain, soil erosion, surface and subsurface flows, soil texture, land management, and vegetation coverage. In this study, based on the transmission mechanism of NPS pollutants, we constructed a five-factor model for predicting the path-through rate of NPS pollutants. The five indices of the hydrological processes, namely the precipitation index (α), terrain index (β), runoff index (TI), subsurface runoff index (LI), and buffer strip retention index (RI), are integrated with the pollution source data, including the rural living, livestock and farmland data, obtained from the national pollution source census. The proposed model was applied to the headwater of the Miyun Reservoir watershed for identifying the areas with high path-through rates of agricultural NPS pollutants. The results demonstrated the following. (1) The simulation accuracy of the model is acceptable in mesoscale watersheds. The total nitrogen (TN) and total phosphorus (TP) agriculture loads were determined as 705.11 t and 3.16 t in 2014, with the relative errors of the simulations being 19.62% and 24.45%, respectively. (2) From the spatial distribution of the agricultural NPS, the TN and TP resource loads were mainly distributed among the upstream of Dage and downstream of Taishitun, as well as the towns of Bakshiying and Gaoling. The major source of TN was found to be farmland, accounting for 47.6%, followed by livestock, accounting for 37.4%. However, the path-through rates of TP were different from those of TN; rural living was the main TP source (65%). (3) The path-through rates of agricultural NPS were the highest for the towns of Wudaoying, Dage, Tuchengzi, Anchungoumen, and Huodoushan, where the path-through rate of TN ranged from 0.17 to 0.26. As for TP, it was highest in Wudaoying, Kulongshan, Dage, and Tuchengzi, with values ranging from 0.012 to 0.019. (4) A comprehensive analysis of the distribution of the NPS pollution load and the path-through rate revealed the towns of Dage, Wudaoying, and Tuchengzi as the critical source areas of agricultural NPS pollutants. Therefore, these towns should be seriously considered for effective watershed management. In addition, compared with field monitoring, the export coefficient model, and the physical-based model, the proposed five-factor model, which is based on the path-through rate and the mechanism of agricultural NPS pollutant transfer, cannot only obtain the spatial distribution characteristics of the path-through rate on a field scale but also be applicable to large-scale watersheds for estimating the path-through rates of NPS pollutants.

scholarly journals Diagnóstico ambiental qualitativo no “lixão” da cidade de Pombal, Paraíba

2017 ◽  
Vol 12 (1) ◽  
pp. 61
Author(s):  
Naiara Angelo Gomes ◽  
José Cleidimário Araújo Leite ◽  
Camilo Allyson Simões de Farias ◽  
Ana Paula Oliveira Silva ◽  
Fernanda Carolina Monteiro Ismael
Keyword(s):  
Adverse Effects ◽  
Solid Waste ◽  
Environmental Changes ◽  
Research Field ◽  
Social Health ◽  
Government Agencies ◽  
Solid Waste Disposal ◽  
Atmospheric Air ◽  
Photo Documentation ◽  
Negative Impacts

<p>A destinação ambientalmente inadequada de resíduos sólidos urbanos provoca diversos impactos negativos no meio ambiente, especialmente nos componentes ambientais: solo, água e ar atmosférico. Neste sentido, para que esses efeitos adversos sejam identificados, é necessário conhecer as características do ambiente na área em questão. Neste estudo, objetivou-se a elaboração de um diagnóstico ambiental qualitativo dos meios físico, biótico e antrópico da área do lixão da cidade de Pombal, Estado da Paraíba. A metodologia utilizada teve por base consultas a órgãos públicos, pesquisas bibliográficas, visitas de campo e fotodocumentação. De acordo com os resultados, verificou-se a ocorrência de várias alterações ambientais adversas significativas nos meios físico, biótico e antrópico, típicas da destinação ambientalmente inadequada de resíduos sólidos em “depósitos” a céu aberto, o que tem resultado em uma degradação ambiental local e acarretado danos sociais, sanitários e ecológicos para o município.</p><p align="center"><strong><em>Qualitative Environmental diagnosis in the “dumpsite” of city Pombal, Paraíba</em></strong></p><p><strong>Abstract</strong><strong>: </strong>Environmentally inadequate disposal of municipal solid waste causes many negative impacts on the environment, especially in the environmental components: soil, water and atmospheric air. Then, for these adverse effects were identified, it is necessary to know the characteristics of the environment in the area in question. This study aims to develop a qualitative environmental diagnosis of the physical, biotic and anthropic environment of the dumpsite of <em>Pombal</em> in state of <em>Paraíba</em>, Brazil. The methodology used in the study was based on consultations in government agencies, bibliographic research, field visits and photo documentation. According to the results, it were noted the occurrence of a number of significant adverse environmental changes in the physical, biotic and anthropic environment, typical of solid waste disposal in "deposits" at  openwork, which has resulted in a local environmental degradation and have caused social, health and ecological damage to the municipality.</p>

Knowledge management within a strategic alliances context: past, present and future

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Nisha Bamel ◽  
Vijay Pereira ◽  
Umesh Bamel ◽  
Giuseppe Cappiello
Keyword(s):  
Knowledge Management ◽  
Strategic Alliances ◽  
Design Methodology ◽  
Strategic Alliance ◽  
Average Rate ◽  
Research Field ◽  
Intellectual Structure ◽  
Content Type ◽  
Current State ◽  
Literature Reviews

Purpose This paper aims at reviewing the extant knowledge management (KM) research field within a strategic alliance context to understand the historical roots, its temporal progression, current state and potential future in a meaningful way. Design/methodology/approach Data for this study was retrieved from the Scopus database using a systematic literature search process. The bibliometric characteristics of 393 research documents were analyzed using bibliometric and structured network analysis. Findings The findings of the study suggest that the publication in the field have been growing with an average rate of 8.48%. This analysis also lists the most productive and impactful authors, main outlets, and the most impactful secondary and primary publication in the field. In addition, the conceptual and intellectual structure of the research field was constructed and discussed. Originality/value This paper uses an objective and quantitative approach by reviewing the related publications and virtually included all the relevant publications in the analysis, which was seen to be uneconomical when doing traditional literature reviews.

Using Diatoms as Ecological and Paleoecological Indicators in Riverine Environments

2007 ◽  
Vol 13 ◽  
pp. 121-130
Author(s):  
Jeffery R. Stone
Keyword(s):  
Spatial Distribution ◽  
Environmental Changes ◽  
Climatic Factors ◽  
Diatom Assemblages ◽  
Meandering River ◽  
Rates Of Change ◽  
Terminal Lakes ◽  
Riverine Systems ◽  
The Impact ◽  
Selection Of

Fossil diatom assemblages are useful for reconstructing past environmental changes in riverine systems. However, few studies have attempted to utilize paleolimnological techniques in these settings. Analysis of sediments from riverine environments can provide key information predating the impact of human development, which cannot be acquired by other means. Paleolimnological techniques can be used to determine the natural variability in these systems and to estimate the magnitude and rates of change that the environment may have undergone as a result of anthropogenic or climatic factors, and to provide realistic goals for management of negatively-impacted systems.Reconstructing past riverine settings requires an understanding of the factors that control the spatial distribution of diatoms in riverine settings; this paper discusses the impact of resources, stressors, and disturbance events, which are the primary controls on the distribution of benthic diatoms in modern riverine environments. A selection of case studies that utilize paleolimnological techniques to infer past stream hydrology are also discussed; these examples encompass the use of fossil diatom assemblages from sediments recovered from lowland floodplain and meandering river systems, estuarine environments, fluvial lakes, arctic deltaic environments, and terminal lakes.

Microbial resistance and resilience in response to environmental changes under the higher intensity of human activities than global average level

2020 ◽  
Vol 26 (4) ◽  
pp. 2377-2389 ◽  
Author(s):  
Laibin Huang ◽  
Junhong Bai ◽  
Xiaojun Wen ◽  
Guangliang Zhang ◽  
Chengdong Zhang ◽  
...  
Keyword(s):  
Human Activities ◽  
Environmental Changes ◽  
Average Level ◽  
Microbial Resistance ◽  
Global Average

scholarly journals Identification of Dominant Factors Affecting Soil Erosion and Water Yield within Ecological Red Line Areas

2020 ◽  
Vol 12 (3) ◽  
pp. 399 ◽  
Author(s):  
Jiangbo Gao ◽  
Yuan Jiang ◽  
Huan Wang ◽  
Liyuan Zuo
Keyword(s):  
Land Use ◽  
Spatial Distribution ◽  
Soil Erosion ◽  
Spatial Heterogeneity ◽  
Remote Sensing Data ◽  
Vegetation Coverage ◽  
Water Yield ◽  
Land Use Type ◽  
Functional Areas ◽  
Red Line

Soil conservation and water retention are important metrics for designating key ecological functional areas and ecological red line (ERL) areas. However, research on the quantitative identification of dominant environmental factors in different ecological red line areas remains relatively inadequate, which is unfavorable for the zone-based management of ecological functional areas. This paper presents a case study of Beijing’s ERL areas. In order to objectively reflect the ecological characteristics of ERL areas in Beijing, which is mainly dominated by mountainous areas, the application of remote sensing data at a high resolution is important for the improvement of model calculation and spatial heterogeneity. Based on multi-source remote sensing data, meteorological and soil observations as well as soil erosion and water yield were calculated using the revised universal soil loss equation (RUSLE) and integrated valuation of ecosystem services and tradeoffs (InVEST) model. Combining the influencing factors, including slope, precipitation, land use type, vegetation coverage, geomorphological type, and elevation, a quantitative attribution analysis was performed on soil erosion and water yield in Beijing’s ERL areas using the geographical detector. The power of each influencing factor and their interaction factors in explaining the spatial distribution of soil erosion or water yield varied significantly among different ERL areas. Vegetation coverage was the dominant factor affecting soil erosion in Beijing’s ERL areas, explaining greater than 30% of its spatial heterogeneity. Land use type could explain the spatial heterogeneity of water yield more than 60%. In addition, the combination of vegetation coverage and slope was found to significantly enhance the spatial distribution of soil erosion (>55% in various ERL areas). The superposition of land use type and slope explained greater than 70% of the spatial distribution for water yield in ERL areas. The geographical detector results indicated that the high soil erosion risk areas and high water yield areas varied significantly among different ERL areas. Thus, in efforts to enhance ERL protection, focus should be placed on the spatial heterogeneity of soil erosion and water yield in different ERL areas.

scholarly journals Evaluation of Humidity Correction Methods for Vaisala RS92 Tropical Sounding Data

2015 ◽  
Vol 32 (3) ◽  
pp. 397-411 ◽  
Author(s):  
Hungjui Yu ◽  
Paul E. Ciesielski ◽  
Junhong Wang ◽  
Hung-Chi Kuo ◽  
Holger Vömel ◽  
...  
Keyword(s):  
Global Climate ◽  
Microwave Radiometer ◽  
Tropical Indian Ocean ◽  
Precipitable Water ◽  
Ground Station ◽  
Uncertainty Estimates ◽  
Wide Range ◽  
Mean Differences ◽  
Surrounding Areas ◽  
Statistical Consistency

AbstractThis study examines the DigiCORA and Global Climate Observing System Reference Upper-Air Network (GRUAN) humidity corrections of Vaisala RS92 radiosondes at three sites over the tropical Indian Ocean and surrounding areas during the Dynamics of the Madden–Julian Oscillation (DYNAMO) field campaign in 2011. The proprietary DigiCORA correction algorithm is built into the ground station software provided by Vaisala, whereas the GRUAN correction is an open source algorithm. Included in the GRUAN data product are uncertainty estimates for their corrections. This information is used to examine the statistical consistency of the various corrections.In general, the algorithms produce a positive relative humidity (RH) correction that increases with altitude related primarily to a solar radiation dry bias adjustment. For example, in daytime soundings the relative RH correction increases from a few percent for temperatures >0°C to 20%–40% between 100 and 200 hPa. Comparison of corrected RH vertical profiles show only small differences (on the order of a few percent or less at any given level) between the DigiCORA and GRUAN algorithms, such that these corrections are considered to be statistically consistent at most levels.In evaluating corrected humidity data with independent estimates of total precipitable water (TPW), good agreement was found at all sites between corrected sounding and ground-based microwave radiometer (MWR) estimates of TPW with mean differences ≤0.9 mm (or <2%), which is well within the uncertainty of these measurements. Overall, the correction algorithms examined herein perform well over a wide range of tropical moisture conditions.

How grass contributes to controlling hillslope erosion

2020 ◽  
Author(s):  
Chengzhong Pan ◽  
Lan Ma
Keyword(s):  
Spatial Distribution ◽  
Soil Erosion ◽  
High Efficiency ◽  
Northern China ◽  
Bare Soil ◽  
Soil Characteristics ◽  
Vegetation Coverage ◽  
Grass Cover ◽  
Run Off ◽  
Set Up

&lt;p&gt;The aim of this study was to investigate how the spatial distribution of grass influenced run-off and erosion from a hillslope with loess and cinnamon soils in the rocky area of Northern China. We set up a trial to test the two soils with different treatments, including bare soil (BS), grass strips on the upper (UGS) and lower (DGS) parts of the slope, grass cover over the entire slope (GS), and a grass carpet on the lower part of the slope (GC), under simulated rainfall conditions. The results showed that the run-off coefficients for the loess and cinnamon soils decreased by between 4% and 20% and by between 2% and 37%, respectively, when covered with grass. Grass spatial distribution had little effect on the run-off, but more effect on erosion than vegetation coverage degree. The most effective location of grass cover for decreasing hillslope erosion was at the foot, and the high efficiency was mainly due to controlling of rill formation and sediment deposition. The soil loss from GS, DGS, and GC on the loess and cinnamon soils was between 77% and 93% less and 55% and 80% less, respectively, compared with the loss from BS. However, the soil characteristics had little effect on soil erosion for well-vegetated slopes. The results highlight the importance of vegetation re-establishment at the foot of hillslope in controlling soil erosion.&lt;/p&gt;

The Life System of Cardiaspina Albitextura (Psyllidae), 1950-74.

1975 ◽  
Vol 23 (4) ◽  
pp. 523 ◽  
Author(s):  
LR Clark ◽  
MJ Dallwitz
Keyword(s):  
Population Density ◽  
Natural Enemies ◽  
Average Rate ◽  
The Other ◽  
Population Densities ◽  
Insect Abundance ◽  
Complete Development ◽  
Rate Of Increase ◽  
Adverse Weather ◽  
Survival And Reproduction

In 1958-63 and 1964-71 the life systems of four kinds of test-forming psyllid that coexist on Eucalyptus blakelyi were investigated intensively in a comparative study of insect abundance. This paper deals mainly with C. albitextura, which was kept under observation from 1950 to 1974. (The others were two species of Glycaspis, Spondyliaspis sp, and Creiis costatus.) The results indicate that the differences in maximal abundance reached by the four kinds of psyllid are mainly the outcome of differences in their ability tg utilize the leaves of the host plant as a source of food, C. albitextura being much more effective than the other species. For the latter, it appears that the principal environmental determinant of abundance was the number of feeding places where nymphs could survive long enough to complete development. That number varied according to foliage and weather. C. albitextura also differed from the other species by having its population densities held for long periods far below the levels at which the food supply would be limiting, by restrictions imposed upon reproduction by adverse weather and foliage conditions (the latter being due partly to poor synchronization between the emergence of adults in spring and the occurrence of foliage attractive for oviposition), and by high mortalities due to natural enemies. The life system of C. albitextura lacks an element that can stabilize abundance at low population densities, but adverse environmental influences usually limit the rate of increase greatly when abundance is low. The magnitude of the average rate of increase to high levels of population density, and the length of time for which high average densities are maintained, depend upon the frequency with which favourable conditions of weather, foliage and predation combine to promote both survival and reproduction.

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