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1. A comparison of single- and multi-site calibration and validation: a case study of SWAT in the Miyun Reservoir watershed, China

Author:
Bai, Jianwen; Shen, Zhenyao; Yan, Tiezhu
Source:
Frontiers of earth science 2017 v.11 no.3 pp. 592-600
ISSN:
2095-0195
Subject:
topography,   etc   ; basins; case studies; climate; humans; hydrologic models; monitoring; pollutants; soil; spatial variation; watersheds; China;     Show all 12 Subjects
Abstract:
... An essential task in evaluating global water resource and pollution problems is to obtain the optimum set of parameters in hydrological models through calibration and validation. For a large-scale watershed, single-site calibration and validation may ignore spatial heterogeneity and may not meet the needs of the entire watershed. The goal of this study is to apply a multi-site calibration and vali ...
DOI:
10.1007/s11707-017-0656-x

2. Acquisition and automated rectification of high-resolution rgb and near-ir aerial photographs to estimate plant biomass and surface topography in arid agro-ecosystems

Author:
SELSAM, PETER; SCHAEPER, WOLFGANG; BRINKMANN, KATJA; BUERKERT, ANDREAS
Source:
Experimental agriculture 2017 v.53 no.1 pp. 144-157
ISSN:
1469-4441
Subject:
topography,   etc   ; aerial photography; agroecosystems; automation; cameras; computer software; cost effectiveness; flight; geometry; georeferencing; landscapes; models; monitoring; phytomass; soil; unmanned aerial vehicles; vegetation;     Show all 17 Subjects
Abstract:
... Increasing image resolution and shrinking camera size facilitates easy mounting of digital cameras on Unmanned Aerial Vehicles (UAVs) to collect large amounts of high-resolution aerial photos for soil surface and vegetation monitoring. Major challenges remain geo-referencing of these images, reliable stitching (mosaicking), elimination of geometric image distortions and compensation of limited ima ...
DOI:
10.1017/S0014479716000089

3. A framework for habitat monitoring and climate change modelling: construction and validation of the Environmental Stratification of Estonia

Author:
Villoslada, Miguel; Bunce, Robert G. H.; Sepp, Kalev; Jongman, Rob H. G.; Metzger, Marc J.; Kull, Tiiu; Raet, Janar; Kuusemets, Valdo; Kull, Ain; Leito, Aivar
Source:
Regional environmental change 2017 v.17 no.2 pp. 335-349
ISSN:
1436-3798
Subject:
topography,   etc   ; agroecosystems; biodiversity; climate change; climatic factors; data collection; environmental impact; habitats; land cover; landscapes; models; monitoring; principal component analysis; soil; Estonia;     Show all 15 Subjects
Abstract:
... Environmental stratifications provide the framework for efficient surveillance and monitoring of biodiversity and ecological resources, as well as modelling exercises. An obstacle for agricultural landscape monitoring in Estonia has been the lack of a framework for the objective selection of monitoring sites. This paper describes the construction and testing of the Environmental Stratification of ...
DOI:
10.1007/s10113-016-1002-7

4. Agricultural Land Fragmentation at Urban Fringes: An Application of Urban-To-Rural Gradient Analysis in Adelaide

Author:
Wadduwage, Suranga; Millington, Andrew; Crossman, Neville D.; Sandhu, Harpinder
Source:
Land 2017 v.6 no.2
ISSN:
2073-445X
Subject:
topography,   etc   ; agricultural land; agroecosystems; geometry; habitat fragmentation; land use change; landscapes; planning; soil; urbanization;     Show all 10 Subjects
Abstract:
... One of the major consequences of expansive urban growth is the degradation and loss of productive agricultural land and agroecosystem functions. Four landscape metrics—Percentage of Land (PLAND), Mean Parcel Size (MPS), Parcel Density (PD), and Modified Simpson’s Diversity Index (MSDI)—were calculated for 1 km × 1 km cells along three 50 km-long transects that extend out from the Adelaide CBD, in ...
DOI:
10.3390/land6020028

5. An evaluation method of the sustainability of water resource in karst region: a case study of Zunyi, China

Author:
Li, Bo; Wang, Ganlu; Ding, Hanghang; Chen, Yulong
Source:
Appl Water Sci 2017 v.7 no.3 pp. 1391-1397
ISSN:
2190-5487
Subject:
topography,   etc   ; case studies; desertification; economic systems; ecosystems; humans; karsts; soil; water requirement; water resources; China;     Show all 11 Subjects
Abstract:
... Water resource is of great significance to the survival and development of human. However, the water resource system in karst regions is sensitive to external interference owing to the special geological processes which cause soil impoverishment, severe rocky desertification and large topographic height difference. Therefore, evaluating the sustainability of the water resource in karst regions is ...
DOI:
10.1007/s13201-015-0362-3

6. Assessing the geomorphic disturbance from fires on coastal dunes near Esperance, Western Australia: implications for dune de-stabilisation

Author:
Shumack, Samuel; Hesse, Paul
Source:
Aeolian research 2017
ISSN:
1875-9637
Subject:
topography,   etc   ; biomass; dunes; germination; remote sensing; sand; soil; vegetation; wildfires; wind; Western Australia;     Show all 11 Subjects
Abstract:
... Fire is commonly listed as a contributing disturbance to dune re-activation. This paper aims to characterise post-fire disturbance to vegetation and soil surface, and aeolian activity on coastal dunes. Field data were collected in February 2016 at two sites on coastal dunes near Esperance, Western Australia (WA) after recent wildfires in November 2015 and January 2016. We measured wind profiles at ...
DOI:
10.1016/j.aeolia.2017.08.005

7. Assessment of Sedimentation Rate in Rain-Fed Irrigation Tank Systems Under Different Agro-Climatic Zones in Karnataka, India

Author:
Satishkumar, U.; Dasog, G. S.; Balakrishnan, P.; Ramaswamy, K.
Source:
Agricultural research 2017 v.6 no.1 pp. 47-56
ISSN:
2249-720X
Subject:
topography,   etc   ; agroclimatology; climatic factors; control methods; flood control; irrigation; longevity; models; prediction; sediment yield; sediments; soil; tanks; water harvesting; India;     Show all 15 Subjects
Abstract:
... The tank systems spread across Karnataka in southern India serve as traditional but sustainable means of water harvesting and flood control measures and a source of protective irrigation. In recent decades, these are fast losing their storage capacity due to sedimentation. To derive appropriate plans for rate of desiltation and reclamation, ruling rate of sedimentation and life expectancy of these ...
DOI:
10.1007/s40003-016-0237-3

8. Availability and species diversity of forest products in a Neotropical rainforest landscape

Author:
Navarrete-Segueda, Armando; Martínez-Ramos, Miguel; Ibarra-Manríquez, Guillermo; Cortés-Flores, Jorge; Vázquez-Selem, Lorenzo; Siebe, Christina
Source:
Forest ecology and management 2017 v.406 pp. 242-250
ISSN:
0378-1127
Subject:
topography,   etc   ; Neotropics; aboveground biomass; aluminum; environmental factors; forest management; forest products; landscapes; linear models; nitrogen; ordination techniques; pH; phosphorus; regression analysis; soil; sustainable forestry; trees; tropical rain forests; Mexico;     Show all 19 Subjects
Abstract:
... Tropical rainforests harbor a high diversity of tree species, offering a potentially rich array of timber (TFP) and non-timber (NTFP) forest products. The supply of such products has been commonly evaluated at the local (plot) scale; however, little is known about how their availability and diversity change at the landscape scale, particularly in heterogeneous environments. This information is cri ...
DOI:
10.1016/j.foreco.2017.08.037

9. Catchment-scale surface water-groundwater connectivity on China's Loess Plateau

Author:
Li, Zhi; Lin, Xueqing; Coles, Anna E.; Chen, Xi
Source:
Catena 2017 v.152 pp. 268-276
ISSN:
0341-8162
Subject:
topography,   etc   ; electrical conductivity; groundwater; hydrologic cycle; isotopes; loess; oxygen; runoff; soil; stream flow; surface water; water management; watersheds; weathering; wet season; China;     Show all 16 Subjects
Abstract:
... Thick loess deposits (up to 200m deep) and a large unsaturated zone (up to 100m below the soil surface) complicate the interactions between surface water and groundwater in China's Loess Plateau, especially in catchments characterized by tableland-gully topography in this region. In the Heihe watershed, electrical conductivity (EC), chloride (Cl) concentrations, and stable water isotope data (δD a ...
DOI:
10.1016/j.catena.2017.01.026

10. CFD wind turbines wake assessment in complex topography

Author:
Daaou Nedjari, Hafida; Guerri, Ouahiba; Saighi, Mohamed
Source:
Energy conversion and management 2017 v.138 pp. 224-236
ISSN:
0196-8904
Subject:
topography,   etc   ; equations; fluid mechanics; models; soil; wind farms; wind speed; wind turbines; Algeria;     Show all 9 Subjects
Abstract:
... The purpose of this work is to numerically study the wind turbine wake evolution in farm over both complex and flat terrain. The nonlinear, aerodynamic interaction between the rotor wake and the wind farm terrain is modeled using the Hybrid method combining CFD (Computational Fluid dynamics) with the actuator disk model. The rotor defined as a function of the wind speed and the thrust coefficient ...
DOI:
10.1016/j.enconman.2017.01.070

11. Characterization and source analysis of water-soluble inorganic ionic species in PM2.5 in Taiyuan city, China

Author:
He, Qiusheng; Yan, Yulong; Guo, Lili; Zhang, Yanli; Zhang, Guixiang; Wang, Xinming
Source:
Atmospheric research 2017 v.184 pp. 48-55
ISSN:
0169-8095
Subject:
topography,   etc   ; air; ammonium nitrate; ammonium sulfate; autumn; biomass; branches; burning; calcium; cations; chlorides; coal; combustion; corn stover; fluorides; heat; industry; inorganic ions; ion exchange chromatography; magnesium; particulates; pollutants; potassium; seasonal variation; sodium; soil; summer; trees; urban areas; wind speed; winter; China; United States;     Show all 33 Subjects
Abstract:
... PM2.5 samples were collected in urban area in Taiyuan for four seasons from August 2009 to April 2010. The Water-soluble inorganic ions (WSI, including F−, Cl−, NO3−, SO42−, Na+, NH4+, K+, Mg2+, and Ca2+) were analyzed by ion chromatography. The daily PM2.5 levels in the field samples varied from 49.90 to 477.93μg/m3 with the mean of 209.54μg/m3, which all largely exceeded the PM2.5 24-hour limita ...
DOI:
10.1016/j.atmosres.2016.10.008

12. Characterizing long-term soil and water erosion and their interactions with various conservation practices in the semi-arid Zulihe basin, Dingxi, Gansu, China

Author:
Zhang, Fu; Xing, Zisheng; Zhao, Chuanyan; Deng, Juli; Yang, Bing; Tian, Qing; Rees, Herb W.; Badreldin, Nasem
Source:
Ecological engineering 2017 v.106 pp. 458-470
ISSN:
0925-8574
Subject:
topography,   etc   ; afforestation; basins; climate change; conservation practices; conservation programs; data collection; grasses; land management; landscapes; pollution load; ponds; rain; regression analysis; runoff; sediment transport; sediment yield; soil; soil conservation; terraces; water conservation; water erosion; watersheds; wet season; China;     Show all 25 Subjects
Abstract:
... Located in a 200–400mm precipitation zone, the Zulihe basin (Zulihe River basin) in China is highly sensitive to climate change and land management. The relatively concentrated rainfall during the wet season (June-September) often leads to severe soil and water erosion. With a dataset collected at the outlet of the basin during 1955-2013, we first examined the trends in precipitation, runoff gener ...
DOI:
10.1016/j.ecoleng.2017.04.056

13. Climate, Topography, and Canopy Chemistry Exert Hierarchical Control Over Soil N Cycling in a Neotropical Lowland Forest

Author:
Osborne, Brooke B.; Nasto, Megan K.; Asner, Gregory P.; Balzotti, Christopher S.; Cleveland, Cory C.; Sullivan, Benjamin W.; Taylor, Philip G.; Townsend, Alan R.; Porder, Stephen
Source:
Ecosystems 2017 v.20 no.6 pp. 1089-1103
ISSN:
1432-9840
Subject:
topography,   etc   ; Neotropics; canopy; catenas; global change; humid zones; landscapes; lowland forests; mineralization; nitrification; nitrogen; nitrogen cycle; nutrient availability; rain; soil; space and time; species diversity; stable isotopes; terraces; tropical forests; Costa Rica;     Show all 21 Subjects
Abstract:
... Nutrient availability varies substantially across lowland tropical forests and constrains their responses to global change. However, interactions among regional, landscape, and local controls of nutrient availability are poorly understood. In that context, we explored the effects of rainfall, topography, and canopy chemistry on nitrogen (N) cycling across the Osa Peninsula (Costa Rica). We sampled ...
DOI:
10.1007/s10021-016-0095-7

14. Climatic thresholds shape northern high‐latitude fire regimes and imply vulnerability to future climate change

Author:
Young, Adam M.; Higuera, Philip E.; Duffy, Paul A.; Hu, Feng Sheng
Source:
Ecography 2017 v.40 no.5 pp. 606-617
ISSN:
0906-7590
Subject:
topography,   etc   ; boreal forests; carbon; carbon cycle; climate change; ecoregions; ecosystems; fire regime; flammability; landscapes; latitude; models; probability; regression analysis; soil; spatial variation; summer; temperature; temporal variation; tundra; wildfires; Alaska;     Show all 22 Subjects
Abstract:
... Boreal forests and arctic tundra cover 33% of global land area and store an estimated 50% of total soil carbon. Because wildfire is a key driver of terrestrial carbon cycling, increasing fire activity in these ecosystems would likely have global implications. To anticipate potential spatiotemporal variability in fire‐regime shifts, we modeled the spatially explicit 30‐yr probability of fire occurr ...
DOI:
10.1111/ecog.02205

15. Comparing catchment hydrologic response to a regional storm using specific conductivity sensors

Author:
Inserillo, E. Ashley; Green, Mark B.; Shanley, James B.; Boyer, Joseph N.
Source:
Hydrological processes 2017 v.31 no.5 pp. 1074-1085
ISSN:
0885-6087
Subject:
topography,   etc   ; correlation; electrical conductivity; human health; humans; hydrograph; infrastructure; land cover; landscapes; lotic systems; rain; riparian buffers; soil; soil organic matter; solutes; storms; stormwater; streams; temperature; watersheds; New Hampshire;     Show all 21 Subjects
Abstract:
... A better understanding of stormwater generation and solute sources is needed to improve the protection of aquatic ecosystems, infrastructure, and human health from large runoff events. Much of our understanding of water and solutes produced during stormflow comes from studies of individual, small headwater catchments. This study compared many different types of catchments during a single large eve ...
DOI:
10.1002/hyp.11091

16. Comparing the use of training data derived from legacy soil pits and soil survey polygons for mapping soil classes

Author:
Heung, Brandon; Hodúl, Matúš; Schmidt, Margaret G.
Source:
Geoderma 2017 v.290 pp. 51-68
ISSN:
0016-7061
Subject:
topography,   etc   ; algorithms; data collection; environmental factors; information systems; logit analysis; models; prediction; principal component analysis; soil; soil classification; soil surveys; uncertainty; British Columbia;     Show all 14 Subjects
Abstract:
... Machine-learners used for digital soil mapping are generally trained using either data derived from field-observed soil pits or from soil survey polygons - although no direct comparison of the accuracy resulting from the two methods has yet to be undertaken. This study examined such a comparison over the Okanagan Valley and Kamloops region of British Columbia where good quality soil pit and soil s ...
DOI:
10.1016/j.geoderma.2016.12.001

17. Deforestation induces shallow landsliding in the montane and subalpine belts of the Urbión Mountains, Iberian Range, Northern Spain

Author:
García-Ruiz, José M.; Beguería, Santiago; Arnáez, José; Sanjuán, Yasmina; Lana-Renault, Noemí; Gómez-Villar, Amelia; Álvarez-Martínez, Javier; Coba-Pérez, Paz
Source:
Geomorphology 2017 v.296 pp. 31-44
ISSN:
0169-555X
Subject:
topography,   etc   ; clay; deforestation; flocks; grasslands; land cover; land use; landslides; mountains; sheep; soil; summer; treeline; Spain;     Show all 14 Subjects
Abstract:
... In this study the spatial distribution of shallow landslides in the upper montane and subalpine belts of the Urbión Mountains (Iberian Range, northern Spain) was investigated, particularly in relation to the spatial organization of deforestation and land cover. The upper montane and subalpine belts have been deforested several times since the Neolithic Period, to enlarge the area of summer grassla ...
DOI:
10.1016/j.geomorph.2017.08.016

18. Determination of Areas Susceptible to Landsliding Using Spatial Patterns of Rainfall from Tropical Rainfall Measuring Mission Data, Rio de Janeiro, Brazil

Author:
Guimarães, Renato Fontes; Machado, Wátila Portela; de Carvalho, Osmar Abílio; Montgomery, David R.; Gomes, Roberto Arnaldo Trancoso; Greenberg, Harvey M.; Cataldi, Márcio; Mendonça, Pedro Coutinho
Source:
ISPRS international journal of geo-information 2017 v.6 no.10
ISSN:
2220-9964
Subject:
topography,   etc   ; cohesion; digital elevation models; landslides; rain; soil; vegetation; Brazil;     Show all 8 Subjects
Abstract:
... Spatial patterns of shallow landslide initiation reflect both spatial patterns of heavy rainfall and areas susceptible to mass movements. We determine the areas most susceptible to shallow landslide occurrence through the calculation of critical soil cohesion and spatial patterns of rainfall derived from TRMM (Tropical Rainfall Measuring Mission) data for Paraty County, State of Rio de Janeiro, Br ...
DOI:
10.3390/ijgi6100289

19. Disturbance automated reference toolset (DART): Assessing patterns in ecological recovery from energy development on the Colorado Plateau

Author:
Nauman, Travis W.; Duniway, Michael C; Villarreal, Miguel L; Poitras, Travis B.
Source:
The Science of the total environment 2017 v.584-585 pp. 476-488
ISSN:
0048-9697
Subject:
topography,   etc   ; Coleogyne ramosissima; artificial intelligence; energy; grasslands; humans; oils; plateaus; satellites; shrublands; soil; vegetation index; United States;     Show all 13 Subjects
Abstract:
... A new disturbance automated reference toolset (DART) was developed to monitor human land surface impacts using soil-type and ecological context. DART identifies reference areas with similar soils, topography, and geology; and compares the disturbance condition to the reference area condition using a quantile-based approach based on a satellite vegetation index. DART was able to represent 26–55% of ...
DOI:
10.1016/j.scitotenv.2017.01.034

20. Disturbance-grazer-vegetation interactions maintain habitat diversity in mountain pasture-woodlands

Author:
Peringer, Alexander; Buttler, Alexandre; Gillet, François; Pătru-Stupariu, Ileana; Schulze, Kiowa A.; Stupariu, Mihai-Sorin; Rosenthal, Gert
Source:
Ecological modelling 2017 v.359 pp. 301-310
ISSN:
0304-3800
Subject:
topography,   etc   ; Fagus sylvatica; Picea abies; canopy gaps; cattle; cutting; forest damage; forests; grasslands; grazing; habitats; landscapes; logging; models; natural resources conservation; photographs; soil; treeline; trees; wilderness; windthrow;     Show all 21 Subjects
Abstract:
... Low-intensity livestock grazing is a widespread management tool in order to maintain habitat diversity in mountain pasture-woodlands for nature conservation purposes. Historical photographs indicate that forest disturbance significantly contributed to forest-grassland mosaic pattern formation. Disturbance-grazer interactions are however poorly understood and the effects of logging or windthrow are ...
DOI:
10.1016/j.ecolmodel.2017.06.012