Rates and processes of aeolian soil erosion in West Greenland

In arid landscapes across the globe, aeolian processes are key drivers of landscape change, but arid Arctic regions are often overlooked. In the Kangerlussuaq region of West Greenland, strong katabatic winds have removed discrete patches of soil and vegetation, exposing unproductive glacial till and bedrock. Although lake-sediment records suggest that landscape destabilization began approximately 1000 years ago, the upland soil erosion has never been directly dated. We use a novel application of lichenometry to estimate the rates and timing of soil erosion. We show that the formation of deflation patches occurred approximately 800–230 years ago, in general agreement with lake-sediment records. In West Greenland, the ‘Little Ice Age’ (AD 1350–1880) was characterized by a cold and arid climate, conditions that increased susceptibility to erosion. On average, deflation patches are expanding at a rate of 2.5 cm yr−1, and variation in the rate of patch expansion cannot be explained by proximity to the Greenland Ice Sheet (GrIS), slope, aspect, elevation, or patch size. An erosional threshold exists in this aeolian system, with climate conditions necessary for patch formation likely harsher than those necessary for continued patch expansion, a result that has implications for land management in arid regions. Currently, deflation patches are expanding throughout the study region and are forming in areas close to the GrIS, but future deflation rates are dependent on projected climate and potential land-use changes. Our results stress the importance of aeolian processes in arid polar landscapes such as Kangerlussuaq, and demonstrate the use of aeolian landforms in paleoclimate reconstructions and predicting future landscape change.

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Holocene lake sediment records from the Disko Bugt region, west Greenland, reveal rapid environmental change ∼4000 years ago

Quaternary International ◽

10.1016/j.quaint.2012.07.301 ◽

2012 ◽

Vol 279-280 ◽

pp. 68-69

Author(s):

Jason Briner

Keyword(s):

Environmental Change ◽

Lake Sediment ◽

West Greenland ◽

Sediment Records ◽

Rapid Environmental Change

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Evaluation of generic farming conditions in Eastern Lithuania

Žemės ūkio mokslai ◽

10.6001/zemesukiomokslai.v22i2.3111 ◽

2015 ◽

Vol 22 (2) ◽

Author(s):

Gintaras Jarašiūnas ◽

Irena Kinderienė

Keyword(s):

Soil Erosion ◽

Agricultural Sector ◽

Slope Aspect ◽

Agricultural Activity ◽

Hilly Terrain ◽

Climate Conditions ◽

Erosion Processes ◽

The Mean ◽

Agricultural Areas ◽

The Impact

Agricultural experts’ perception and knowledge towards farming conditions and natural agro-environmental problems are important to develop a sustainable rural strategy and may serve when planning land use in sloping agricultural areas to avoid land abandonment. The objective of investigations was to analyze the attitudes of agricultural experts in the Eastern Lithuania region towards the state of the generic agrarian sector, soil erosion processes and natural handicaps. Replies of respondents indicated that the means (the Likert Scale) of the evaluation towards the items “Soil quality”, “Agricultural sector development” and “Land suitability for generic agricultural activity” were 2.68, 3.11 and 2.73, respectively. The evaluations indicating that the mean score perceived by respondents towards impact of soil erosion on common farming activity in the region was 2.63. A questionnaire study showed that respondents recognized that the impact of terrain and soil texture factors on the potential of soil erosion processes is the highest in the region, thus the factor of soil type has been evaluated as the least important. The most frequently noticed topographical parameter of the terrain influencing the intensity of soil erosion was slope steepness (63.1% of respondents), followed by slope aspect (21.1%) and length (15.8%). Hilly terrain and soil acidity constraints by frequency 24.5 and 18.9%, respectively, have showed the most important attitude of respondents, in the content of the natural handicaps limiting successful farming activity in the region. However, the study disclosed that unfavourable climate conditions and soil cover diversity were the two least crucial natural constraints for farming. These empirical findings intended to bring benefits and can help in decision-making framework in order to decide the best soil conservation measures and improving farming conditions in agricultural areas under natural handicaps.

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FROM PRE-SETTLEMENT TO THE 21ST CENTURY - LAKE SEDIMENT RECORDS OF LAND USE AND CLIMATE CHANGE IN NEW ENGLAND

10.1130/abs/2016am-287650 ◽

2016 ◽

Author(s):

Lisa A. Doner ◽

Keyword(s):

Climate Change ◽

Land Use ◽

New England ◽

Lake Sediment ◽

21St Century ◽

Sediment Records

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Using SWAT to Evaluate Streamflow and Lake Sediment Loading in the Xinjiang River Basin with Limited Data

Water ◽

10.3390/w12010039 ◽

2019 ◽

Vol 12 (1) ◽

pp. 39 ◽

Cited By ~ 2

Author(s):

Lifeng Yuan ◽

Kenneth J. Forshay

Keyword(s):

Soil Erosion ◽

River Basin ◽

Lake Sediment ◽

Sediment Yield ◽

Sediment Load ◽

Poyang Lake ◽

Sediment Source ◽

Sediment Loading ◽

Source Areas ◽

Annual Sediment

Soil erosion and lake sediment loading are primary concerns of watershed managers around the world. In the Xinjiang River Basin of China, severe soil erosion occurs primarily during monsoon periods, resulting in sediment flow into Poyang Lake and subsequently causing lake water quality deterioration. Here, we identified high-risk soil erosion areas and conditions that drive sediment yield in a watershed system with limited available data to guide localized soil erosion control measures intended to support reduced sediment load into Poyang Lake. We used the Soil and Water Assessment Tool (SWAT) model to simulate monthly and annual sediment yield based on a calibrated SWAT streamflow model, identified where sediment originated, and determined what geographic factors drove the loading within the watershed. We applied monthly and daily streamflow discharge (1985–2009) and monthly suspended sediment load data (1985–2001) to Meigang station to conduct parameter sensitivity analysis, calibration, validation, and uncertainty analysis of the model. The coefficient of determination (R2), Nash–Sutcliffe efficiency (NSE), percent bias (PBIAS), and RMSE -observation’s standard deviation ratio (RSR) values of the monthly sediment load were 0.63, 0.62, 3.8%, and 0.61 during calibration, respectively. Spatially, the annual sediment yield rate ranged from 3 ton ha−1year−1 on riparian lowlands of the Xinjiang main channel to 33 ton ha−1year−1 on mountain highlands, with a basin-wide mean of 19 ton ha−1year−1. The study showed that 99.9% of the total land area suffered soil loss (greater than 5 ton ha−1year−1). More sediment originated from the southern mountain highlands than from the northern mountain highlands of the Xinjiang river channel. These results suggest that specific land use types and geographic conditions can be identified as hotspots of sediment source with relatively scarce data; in this case, orchards, barren lands, and mountain highlands with slopes greater than 25° were the primary sediment source areas. This study developed a reliable, physically-based streamflow model and illustrates critical source areas and conditions that influence sediment yield.

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Hybrid Integration Approach of Entropy with Logistic Regression and Support Vector Machine for Landslide Susceptibility Modeling

Entropy ◽

10.3390/e20110884 ◽

2018 ◽

Vol 20 (11) ◽

pp. 884 ◽

Cited By ~ 28

Author(s):

Tingyu Zhang ◽

Ling Han ◽

Wei Chen ◽

Himan Shahabi

Keyword(s):

Support Vector Machine ◽

Logistic Regression ◽

Landslide Susceptibility ◽

Shaanxi Province ◽

Slope Aspect ◽

Support Vector ◽

Operating Characteristics ◽

Study Region ◽

Susceptibility Maps ◽

Landslide Susceptibility Maps

The main purpose of the present study is to apply three classification models, namely, the index of entropy (IOE) model, the logistic regression (LR) model, and the support vector machine (SVM) model by radial basis function (RBF), to produce landslide susceptibility maps for the Fugu County of Shaanxi Province, China. Firstly, landslide locations were extracted from field investigation and aerial photographs, and a total of 194 landslide polygons were transformed into points to produce a landslide inventory map. Secondly, the landslide points were randomly split into two groups (70/30) for training and validation purposes, respectively. Then, 10 landslide explanatory variables, such as slope aspect, slope angle, altitude, lithology, mean annual precipitation, distance to roads, distance to rivers, distance to faults, land use, and normalized difference vegetation index (NDVI), were selected and the potential multicollinearity problems between these factors were detected by the Pearson Correlation Coefficient (PCC), the variance inflation factor (VIF), and tolerance (TOL). Subsequently, the landslide susceptibility maps for the study region were obtained using the IOE model, the LR–IOE, and the SVM–IOE model. Finally, the performance of these three models was verified and compared using the receiver operating characteristics (ROC) curve. The success rate results showed that the LR–IOE model has the highest accuracy (90.11%), followed by the IOE model (87.43%) and the SVM–IOE model (86.53%). Similarly, the AUC values also showed that the prediction accuracy expresses a similar result, with the LR–IOE model having the highest accuracy (81.84%), followed by the IOE model (76.86%) and the SVM–IOE model (76.61%). Thus, the landslide susceptibility map (LSM) for the study region can provide an effective reference for the Fugu County government to properly address land planning and mitigate landslide risk.

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Late Holocene environmental reconstructions and their implications on flood events, typhoon, and agricultural activities in NE Taiwan

Climate of the Past ◽

10.5194/cp-10-1857-2014 ◽

2014 ◽

Vol 10 (5) ◽

pp. 1857-1869 ◽

Cited By ~ 19

Author(s):

L.-C. Wang ◽

H. Behling ◽

T.-Q. Lee ◽

H.-C. Li ◽

C.-A. Huh ◽

...

Keyword(s):

Little Ice Age ◽

Southern Oscillation ◽

Phase 1 ◽

Warm Pool ◽

Ice Age ◽

Agricultural Activities ◽

Flood Events ◽

Climate Conditions ◽

Hydrological Conditions ◽

Enso Events

Abstract. We reconstructed paleoenvironmental changes from a sediment archive of a lake in the floodplain of the Ilan Plain of NE Taiwan on multi-decadal resolution for the last ca. 1900 years. On the basis of pollen and diatom records, we evaluated past floods, typhoons, and agricultural activities in this area which are sensitive to the hydrological conditions in the western Pacific. Considering the high sedimentation rates with low microfossil preservations in our sedimentary record, multiple flood events were. identified during the period AD 100–1400. During the Little Ice Age phase 1 (LIA 1 – AD 1400–1620), the abundant occurrences of wetland plant (Cyperaceae) and diatom frustules imply less flood events under stable climate conditions in this period. Between AD 500 and 700 and the Little Ice Age phase 2 (LIA 2 – AD 1630–1850), the frequent typhoons were inferred by coarse sediments and planktonic diatoms, which represented more dynamical climate conditions than in the LIA 1. By comparing our results with the reconstructed changes in tropical hydrological conditions, we suggested that the local hydrology in NE Taiwan is strongly influenced by typhoon-triggered heavy rainfalls, which could be influenced by the variation of global temperature, the expansion of the Pacific warm pool, and the intensification of El Niño–Southern Oscillation (ENSO) events.

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Investigation of Climate and Land Use Change Impacts on Stream Flow of Guder Catchment, Ethiopia

10.21203/rs.3.rs-976225/v1 ◽

2021 ◽

Author(s):

Bekam Bekele Gulti ◽

Boja Mokonnen Manyazew ◽

Abdulkerim Bedewi Serur

Keyword(s):

Climate Change ◽

Land Use ◽

Stream Flow ◽

Open Space ◽

Smart Growth ◽

Assessment Model ◽

Study Region ◽

Climate Conditions ◽

Change Impact ◽

The Impact

Abstract Climate change (CC) and land use/cover change (LUCC) are the main drivers of streamflow change. In this paper, we investigate the impact of climate and LULC change impact on stream flow of Guder catchment by using Soil and Water Assessment model (SWAT). The scenarios were designed in a way that LULC was changed while climate conditions remain constant; LULC was then held constant under a changing climate and combined effect of both. The result shows that, the combined impacts of climate change and LULC dynamics can be rather different from the effects that follow-on from LULC or climate change alone. Streamflow would be more sensitive to climate change than to the LULC changes scenario, even though changes in LULC have far-reaching influences on streamflow in the study region. A comprehensive strategy of low impact developments, smart growth, and open space is critical to handle future changes to streamflow systems.

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The Little Ice Age, the climatic background of present-day warming in Europe

Cuadernos de Investigación Geográfica ◽

10.18172/cig.3402 ◽

2018 ◽

Vol 44 (1) ◽

pp. 7 ◽

Cited By ~ 1

Author(s):

M. Oliva

Keyword(s):

Little Ice Age ◽

Ice Age ◽

Future Research ◽

Climate Regime ◽

European Continent ◽

Economic Implications ◽

Climate Conditions ◽

Wide Range ◽

Show Evidence ◽

Spatio Temporal

The Little Ice Age (LIA) constitutes the coldest period of the last millennia in Europe. A wide range of natural and historical records show evidence of colder climate conditions between the 14th and 19th centuries, together with a higher frequency of extreme hydroclimatic events. During these centuries, temperatures and precipitations showed different spatio-temporal patterns across Europe. This Special Issue includes eleven scientific works focusing on the climate regime, environmental dynamics as well as socio-economic implications of the LIA in Europe. Besides, this paper also identifies key guidelines for future research on the LIA causes and its consequences on environmental systems in the European continent.

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