scholarly journals A Spatially Distributed Investigation of Stream Water Temperature in a Contemporary Mixed-Land-Use Watershed

Water ◽  
2020 ◽  
Vol 12 (6) ◽  
pp. 1756 ◽  
Author(s):  
Jason P. Horne ◽  
Jason A. Hubbart
Keyword(s):  
Land Use ◽  
Water Temperature ◽  
Agricultural Land ◽  
Stream Water ◽  
Winter Season ◽  
Negative Relationship ◽  
Conservation Strategies ◽  
Land Use Land Cover ◽  
Spatially Distributed ◽  
Mixed Land Use

Stream water temperature (°C) is an important physical variable that influences many biological and abiotic water quality processes. The intermingled mosaic of land-use/land-cover (LULC) types and corresponding variability in stream water temperature (Tw) processes in contemporary mixed-land-use watersheds necessitate research to advance management and policy decisions. Water temperature was analyzed from 21 gauging sites using a nested-scale experimental watershed study design. Results showed that forested land use was negatively correlated (α = 0.05) with mean and maximum Tw. Agricultural land use was significantly positively correlated (α = 0.05) with maximum Tw except during the spring season. Mixed development and Tw were significantly correlated (α = 0.05) at quarterly and monthly timescales. Correlation trends in some reaches were reversed between the winter and summer seasons, contradicting previous research. During the winter season, mixed development showed a negative relationship with minimum Tw and mean Tw. During the summer season, higher minimum, maximum, and mean Tw correlations were observed. Advanced understanding generated through this high-resolution investigation improves land managers’ ability to improve conservation strategies in freshwater aquatic ecosystems of contemporary watersheds.

scholarly journals Using occupancy models to assess the direct and indirect impacts of agricultural expansion on species’ populations

2020 ◽  
Vol 29 (13) ◽  
pp. 3669-3688
Author(s):  
Asunción Semper-Pascual ◽  
Julieta Decarre ◽  
Matthias Baumann ◽  
Micaela Camino ◽  
Yamil Di Blanco ◽  
...  
Keyword(s):  
Land Use ◽  
Land Use Change ◽  
Direct Effect ◽  
Indirect Effects ◽  
Agricultural Land ◽  
Conservation Strategies ◽  
Agricultural Expansion ◽  
Direct And Indirect Effects ◽  
Occupancy Models ◽  
Occupancy Modelling

Abstract Land-use change is a global threat to biodiversity, but how land-use change affects species beyond the direct effect of habitat loss remains poorly understood. We developed an approach to isolate and map the direct and indirect effects of agricultural expansion on species of conservation concern, using the threatened giant anteater (Myrmecophaga tridactyla) in the Gran Chaco as an example. We reconstructed anteater occupancy change between 1985 and 2015 by fitting single-season occupancy models with contemporary camera-trap data and backcasting the models to 1985 and 2000 land-cover/use maps. Based on this, we compared the area of forest loss (direct effect of agricultural expansion) with the area where forests remained but occupancy still declined (indirect effect of agricultural expansion). Anteater occupancy decreased substantially since 1985, particularly after 2000 when agriculture expanded rapidly. Between 1985 and 2015, ~ 64,000 km2 of forest disappeared, yet occupancy declined across a larger area (~ 102,000 km2), extending far into seemingly untransformed habitat. This suggests that widespread sink habitat has emerged due to agricultural land-use change, and that species may lose their habitat through direct and indirect effects of agricultural expansion, highlighting the urgent need for broad-scale conservation planning in the Chaco. Appropriate management responses could proactively protect more habitat where populations are stable, and restore habitat or address causes of mortality in areas where declines occur. Our work also highlights how occupancy modelling combined with remote sensing can help to detect the direct and indirect effects of agricultural expansion, providing guidance for spatially targeting conservation strategies to halt extinctions.

Effects of land-use/land-cover changes on land crab,Cardisoma guanhumi, abundance in Puerto Rico

2008 ◽  
Vol 24 (4) ◽  
pp. 417-423 ◽  
Author(s):  
Yogani Govender ◽  
Alberto M. Sabat ◽  
Elvira Cuevas
Keyword(s):  
Land Use ◽  
Puerto Rico ◽  
Land Cover ◽  
Soil Temperature ◽  
Surface Soil ◽  
Negative Relationship ◽  
Land Use Land Cover ◽  
Land Crab ◽  
Cardisoma Guanhumi ◽  
Crab Abundance

AbstractThe land crabCardisoma guanhumipopulations have been on the decline in Puerto Rico for the last three decades. While some studies suggest overexploitation and pesticides as causing the observed population declines, the effect of land-use/land-cover (LULC) changes have not been investigated. In this study we compared the abundance and size ofCardisoma guanhumiin five different LULC types (mangroves, grasslands, forest, urban and industrial), and investigated the relationship between differences in physical microhabitat conditions among the LULC types with crab abundance and size. Although no significant differences in size were found among the different LULC types, crabs were significantly less abundant in grassland sites. Surface soil temperature, depth to groundwater and air temperature were found to vary significantly among the LULC types. Of these, only surface soil temperatures had a significant negative relationship with crab abundance. It appears that high variation in soil temperature and a high groundwater table observed in the grasslands is most detrimental to crabs. Interestingly, during the time when land crab populations declined there was corresponding change of LULC from agriculture to grasslands.Cardisoma guanhumiis resilient to changes in LULC, however, changes that alter their access to groundwater and escape from high soil temperature reduce their habitat.

Level of Urbanization and Land Use/Land Cover Landscape Pattern of Relationship Analysis

2013 ◽  
Vol 316-317 ◽  
pp. 197-199 ◽  
Author(s):  
Chen Guang Xu ◽  
Amat Anwar
Keyword(s):  
Land Use ◽  
Population Density ◽  
Land Use Change ◽  
Landscape Pattern ◽  
Agricultural Land ◽  
Land Use Intensity ◽  
Land Use Land Cover ◽  
Rapid Urbanization ◽  
Relationship Analysis ◽  
The Relationship

On the basis of analysis of the development of urbanization and land use change in Zhengzhou City in2004-2010, The drive mechanism of the intensity of land use change in the research context of rapid urbanization, To explore the degree of land use change human driving factors, Drive and build a model, The results show that: Unit of agricultural land and the ratio of the output value of the land for construction as well as population density and land use intensity positive correlation, Making land use intensity tends to increase, The population density growth, Urbanization of the population and economic non-farm is the main driving factor for the intensity of land use change. And then proceed to the analysis of the spatial pattern of Zhengzhou City, Investigate the level of urbanization and land use / cover the relationship between landscape pattern.

scholarly journals Classification of various land features using RISAT-1 dual polarimetric data

2014 ◽  
Vol XL-8 ◽  
pp. 833-837 ◽  
Author(s):  
V. N. Mishra ◽  
P. Kumar ◽  
D. K. Gupta ◽  
R. Prasad
Keyword(s):  
Land Use ◽  
Land Cover ◽  
Agricultural Land ◽  
Uttar Pradesh ◽  
Land Cover Classification ◽  
Support Vector ◽  
Land Use Land Cover ◽  
Remotely Sensed Data ◽  
Sar Data ◽  
Land Cover Maps

Land use land cover classification is one of the widely used applications in the field of remote sensing. Accurate land use land cover maps derived from remotely sensed data is a requirement for analyzing many socio-ecological concerns. The present study investigates the capabilities of dual polarimetric C-band SAR data for land use land cover classification. The MRS mode level 1 product of RISAT-1 with dual polarization (HH & HV) covering a part of Varanasi district, Uttar Pradesh, India is analyzed for classifying various land features. In order to increase the amount of information in dual-polarized SAR data, a band HH + HV is introduced to make use of the original two polarizations. Transformed Divergence (TD) procedure for class separability analysis is performed to evaluate the quality of the statistics prior to image classification. For most of the class pairs the TD values are greater than 1.9 which indicates that the classes have good separability. Non-parametric classifier Support Vector Machine (SVM) is used to classify RISAT-1 data with optimized polarization combination into five land use land cover classes like urban land, agricultural land, fallow land, vegetation and water bodies. The overall classification accuracy achieved by SVM is 95.23 % with Kappa coefficient 0.9350.

scholarly journals Assessment of Change in the Built-Up Index of Uyo Metropolis and Its Environs Using Remote Sensing

2019 ◽  
Vol 4 (6) ◽  
pp. 84-89 ◽  
Author(s):  
Aniekan Effiong Eyoh ◽  
Akwaowo Ekpa
Keyword(s):  
Remote Sensing ◽  
Land Use ◽  
Quantitative Analysis ◽  
Land Cover ◽  
Agricultural Land ◽  
Remote Sensing Data ◽  
Land Use Land Cover ◽  
Positive Growth ◽  
Bare Land ◽  
Erdas Imagine

The research was aim at assessing the change in the Built-up Index of Uyo metropolis and its environs from 1986 to 2018, using remote sensing data. To achieve this, a quantitative analysis of changes in land use/land cover within the study area was undertaken using remote sensing dataset of Landsat TM, ETM+ and OLI sensor images of 1986, 2000 and 2018 respectively. Supervised classification, using the maximum likelihood algorithm, was used to classify the study area into four major land use/land cover types; built-up land, bare land/agricultural land, primary swamp vegetation and secondary vegetation. Image processing was carried out using ERDAS IMAGINE and ArcGIS software. The Normalised Difference Built-up Index (NDBI) was calculated to obtain the built-up index for the study area in 1986, 2000 and 2018 as -0.20 to +0.45, -0.13 to +0.55 and -0.19 to +0.63 respectively. The result of the quantitative analysis of changes in land use/land cover indicated that Built-up Land had been on a constant and steady positive growth from 6.76% in 1986 to 11.29% in 2000 and 44.04% in 2018.

scholarly journals Retrieval of Land-Use/Land Cover Change (LUCC) Maps and Urban Expansion Dynamics of Hyderabad, Pakistan via Landsat Datasets and Support Vector Machine Framework

2021 ◽  
Vol 13 (16) ◽  
pp. 3337
Author(s):  
Shaker Ul Din ◽  
Hugo Wai Leung Mak
Keyword(s):  
Land Use ◽  
Support Vector Machine ◽  
Land Cover ◽  
Land Cover Change ◽  
Agricultural Land ◽  
Urban Expansion ◽  
Support Vector ◽  
Land Use Land Cover ◽  
Landsat Images ◽  
Barren Land

Land-use/land cover change (LUCC) is an important problem in developing and under-developing countries with regard to global climatic changes and urban morphological distribution. Since the 1900s, urbanization has become an underlying cause of LUCC, and more than 55% of the world’s population resides in cities. The speedy growth, development and expansion of urban centers, rapid inhabitant’s growth, land insufficiency, the necessity for more manufacture, advancement of technologies remain among the several drivers of LUCC around the globe at present. In this study, the urban expansion or sprawl, together with spatial dynamics of Hyderabad, Pakistan over the last four decades were investigated and reviewed, based on remotely sensed Landsat images from 1979 to 2020. In particular, radiometric and atmospheric corrections were applied to these raw images, then the Gaussian-based Radial Basis Function (RBF) kernel was used for training, within the 10-fold support vector machine (SVM) supervised classification framework. After spatial LUCC maps were retrieved, different metrics like Producer’s Accuracy (PA), User’s Accuracy (UA) and KAPPA coefficient (KC) were adopted for spatial accuracy assessment to ensure the reliability of the proposed satellite-based retrieval mechanism. Landsat-derived results showed that there was an increase in the amount of built-up area and a decrease in vegetation and agricultural lands. Built-up area in 1979 only covered 30.69% of the total area, while it has increased and reached 65.04% after four decades. In contrast, continuous reduction of agricultural land, vegetation, waterbody, and barren land was observed. Overall, throughout the four-decade period, the portions of agricultural land, vegetation, waterbody, and barren land have decreased by 13.74%, 46.41%, 49.64% and 85.27%, respectively. These remotely observed changes highlight and symbolize the spatial characteristics of “rural to urban transition” and socioeconomic development within a modernized city, Hyderabad, which open new windows for detecting potential land-use changes and laying down feasible future urban development and planning strategies.

scholarly journals Land Use and Land Cover Change as an Indicator of Watershed Urban Development in the Kenyan Lake Victoria Basin

2021 ◽  
Vol 16 (2) ◽  
pp. 335-345
Author(s):  
Dancan Otieno Onyango ◽  
Christopher O. Ikporukpo ◽  
John O. Taiwo ◽  
Stephen B. Opiyo
Keyword(s):  
Land Use ◽  
Land Cover ◽  
Agricultural Land ◽  
Lake Victoria ◽  
Water Bodies ◽  
Natural Environments ◽  
Land Use Land Cover ◽  
Lake Victoria Basin ◽  
Ecological Value ◽  
Bare Land

The socio-economic and ecological value of Lake Victoria is threatened by significant regional development and urbanization. This study analyzed spatial-temporal land use/land cover changes in the Kenyan Lake Victoria basin from 1978–2018 using Landsat 3, 4-5 and 8 imagery, with a view to identifying the extent and potential impacts of urbanization on the basin. Supervised image classification was undertaken following the Maximum Likelihood algorithm to generate land use/land cover maps at ten-year intervals. Results indicate that the basin is characterized by six main land use/land cover classes namely, agricultural land, water bodies, grasslands and vegetation, bare land, forests and built-up areas. Further, the results indicate that the basin has experienced net increases in built-up areas (+97.56%), forests (+17.30%) and agricultural land (+3.54%) over the last 40 years. During the same period, it experienced net losses in grassland and vegetation (-37.36%), bare land (-9.28%) and water bodies (-2.19%). Generally, the changing landscapes in the basin are characterized by conversion of natural environments to built-up environments and driven by human activities, urban populations and public policy decisions. The study therefore recommends the establishment of a land use system that creates a balance between the ecological realm and sustainable development.

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