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2022 ◽  
Author(s):  
Ziyan Li ◽  
Derek Elsworth ◽  
Chaoyi Wang

Abstract Fracturing controls rates of mass, chemical and energy cycling within the crust. We use observed locations and magnitudes of microearthquakes (MEQs) to illuminate the evolving architecture of fractures reactivated and created in the otherwise opaque subsurface. We quantitatively link seismic moments of laboratory MEQs to the creation of porosity and permeability at field scale. MEQ magnitudes scale to the slipping patch size of remanent fractures reactivated in shear - with scale-invariant roughnesses defining permeability evolution across nine decades of spatial volumes – from centimeter to decameter scale. This physics-inspired seismicity-permeability linkage enables hybrid machine learning (ML) to constrain in-situ permeability evolution at verifiable field-scales (~10 m). The ML model is trained on early injection and MEQ data to predict the dynamic evolution of permeability from MEQ magnitudes and locations, alone. The resulting permeability maps define and quantify flow paths verified against ground truths of permeability.


Author(s):  
M. Y. Ozturk ◽  
I. Colkesen

Abstract. The aim of the current study was to evaluate the performance of patch-based classification technique in land use/land cover classification and to investigate the effect of patch size in thematic map accuracy. To reach desired goal, recently proposed ensemble learning classifiers (i.e., XGBoost and CatBoost) were utilized to classify produced image patches obtained from high-resolution WorldView-2 (WV-2) satellite image. . In order to analyse the effect of varying patch size on classification accuracy, three different window sizes (i.e., 3 × 3, 7 × 7 and 11 × 11) were applied to WV-2 imagery for extracting image patches. Constructed image patches were classified using XGBoost and CatBoost ensemble learning classifiers and thematic maps were constructed for varying patch sizes. Results showed that while XGBoost and CatBoost showed similar classification performances for varying patch size and the estimated highest overall accuracy were %68, %82 and %92 for 11x11, 7 × 7 and 11 × 11 patch sizes, respectively. These findings confirmed that defining class boundaries on the high-resolution image using smaller patches increases the accuracy of thematic maps. In addition, results of patch-based classification were compared the results of LULC maps produced by same classifiers using pixel-based classification method. Overall accuracy of pixel-by-pixel classification of WV-2 image reached to about %94. Furthermore, CatBoost showed superior classification performance in all time compared to XGBoost. All in all, pixel-based CatBoost was found to be more successful in LULC mapping of fine resolution image.


2021 ◽  
Vol 9 ◽  
Author(s):  
Ingrid de Mattos ◽  
Bárbara Zimbres ◽  
Jader Marinho-Filho

Landscape conversion of natural environments into agriculture and pasture are driving a marked biodiversity decline in the tropics. Consequences of fragmentation might depend upon habitat amount in the landscape, while the quality of remnants can also affect some species. These factors have been poorly studied in relation to different spatial scales. Furthermore, the impacts of these human-driven alterations may go beyond species loss, possibly causing a loss of ecosystem function and services. In this study, we investigated how changes in landscape configuration (patch size and isolation), habitat loss (considering a landscape gradient of 10, 25, and 40% of remnant forest cover), and habitat quality (forest structure) affect small mammal abundance, richness, taxonomic/functional diversity, and species composition in fragmented landscapes of semideciduous forests in the Brazilian Cerrado. Analyses were performed separately for habitat generalists and forest specialists. We live-trapped small mammals and measured habitat quality descriptors four times in 36 forest patches over the years 2018 and 2019, encompassing both rainy and dry seasons, with a total capture effort of 45,120 trap-nights. Regression analyses indicated that the effect of landscape configuration was not dependent on the proportion of habitat amount in the landscape to determine small mammal assemblages. However, both patch size and habitat loss impacted different aspects of the assemblages in distinct ways. Smaller patches were mainly linked to an overall increase in small mammal abundance, while the abundance of habitat generalists was also negatively affected by habitat amount. Generalist species richness was determined by the proportion of habitat amount in the landscape. Specialist richness was influenced by patch forest quality only, suggesting that species with more demanding habitat requirements might respond to fragmentation and habitat loss at finer scales. Taxonomic or functional diversity were not influenced by landscape structure or habitat quality. However, patch size and habitat amount in the landscape were the major drivers of change in small mammal species composition in semideciduous forests in the Brazilian savanna.


2021 ◽  
Author(s):  
◽  
Nicky OliverSmith

<p>Urban revegetation programmes are an important contribution to the biodiversity of our landscape environment. Wellington city has, for nearly two decades, promoted revegetation of the city with a focus in latter years on eco-sourced native species. This is a substantial urban greening project planting 100,000 native plants per annum. This thesis analyses the native revegetation programme and posits recommendations for continuance and enhancement for consideration.  Data were collected from a sample set of twenty revegetated sites and four reference sites in Wellington city. Two transects per site were set up with invertebrate pitfall traps, lizard pitfall traps, lizard tree covers, bird count stations and vegetation surveys. The data were collected over a twelve-month period. Ordination was used to examine the community composition of revegetation sites in relation to each other and the four reference sites. Multiple regression was used to examine the influence of patch age, patch size, isolation and residential land cover upon a range of biodiversity variables.   The key findings of this study are that revegetated sites lacked the level of ground cover by native seedlings that were characteristic of the mature reference sites. Also found was that revegetation sites in Wellington City require around ten years of growth before natural regeneration of native seedlings began to become apparent.  Large native birds were more likely to be found in close proximity to mature primary bush, confirming that mature primary bush is an essential element of the landscape. Weta were found in increased numbers as distance from mature primary bush increased. Northern grass skinks were the only species of lizard found, in association with a higher proportion of residential area in the matrix.   The key management recommendations of this study are; the development of a collaborative connective strategy; further enrichment planting designed to maximize structural diversity over time; the investment in well planned robust monitoring programmes.  This research contributes to the understanding of biodiversity outcomes of an urban native revegtation programme, providing baseline data for future monitoring purposes.</p>


2021 ◽  
Author(s):  
◽  
Nicky OliverSmith

<p>Urban revegetation programmes are an important contribution to the biodiversity of our landscape environment. Wellington city has, for nearly two decades, promoted revegetation of the city with a focus in latter years on eco-sourced native species. This is a substantial urban greening project planting 100,000 native plants per annum. This thesis analyses the native revegetation programme and posits recommendations for continuance and enhancement for consideration.  Data were collected from a sample set of twenty revegetated sites and four reference sites in Wellington city. Two transects per site were set up with invertebrate pitfall traps, lizard pitfall traps, lizard tree covers, bird count stations and vegetation surveys. The data were collected over a twelve-month period. Ordination was used to examine the community composition of revegetation sites in relation to each other and the four reference sites. Multiple regression was used to examine the influence of patch age, patch size, isolation and residential land cover upon a range of biodiversity variables.   The key findings of this study are that revegetated sites lacked the level of ground cover by native seedlings that were characteristic of the mature reference sites. Also found was that revegetation sites in Wellington City require around ten years of growth before natural regeneration of native seedlings began to become apparent.  Large native birds were more likely to be found in close proximity to mature primary bush, confirming that mature primary bush is an essential element of the landscape. Weta were found in increased numbers as distance from mature primary bush increased. Northern grass skinks were the only species of lizard found, in association with a higher proportion of residential area in the matrix.   The key management recommendations of this study are; the development of a collaborative connective strategy; further enrichment planting designed to maximize structural diversity over time; the investment in well planned robust monitoring programmes.  This research contributes to the understanding of biodiversity outcomes of an urban native revegtation programme, providing baseline data for future monitoring purposes.</p>


2021 ◽  
Vol 11 ◽  
Author(s):  
Yaoying Liu ◽  
Zhaocai Chen ◽  
Jinyuan Wang ◽  
Xiaoshen Wang ◽  
Baolin Qu ◽  
...  

PurposeThis study focused on predicting 3D dose distribution at high precision and generated the prediction methods for nasopharyngeal carcinoma patients (NPC) treated with Tomotherapy based on the patient-specific gap between organs at risk (OARs) and planning target volumes (PTVs).MethodsA convolutional neural network (CNN) is trained using the CT and contour masks as the input and dose distributions as output. The CNN is based on the “3D Dense-U-Net”, which combines the U-Net and the Dense-Net. To evaluate the model, we retrospectively used 124 NPC patients treated with Tomotherapy, in which 96 and 28 patients were randomly split and used for model training and test, respectively. We performed comparison studies using different training matrix shapes and dimensions for the CNN models, i.e., 128 ×128 ×48 (for Model I), 128 ×128 ×16 (for Model II), and 2D Dense U-Net (for Model III). The performance of these models was quantitatively evaluated using clinically relevant metrics and statistical analysis.ResultsWe found a more considerable height of the training patch size yields a better model outcome. The study calculated the corresponding errors by comparing the predicted dose with the ground truth. The mean deviations from the mean and maximum doses of PTVs and OARs were 2.42 and 2.93%. Error for the maximum dose of right optic nerves in Model I was 4.87 ± 6.88%, compared with 7.9 ± 6.8% in Model II (p=0.08) and 13.85 ± 10.97% in Model III (p&lt;0.01); the Model I performed the best. The gamma passing rates of PTV60 for 3%/3 mm criteria was 83.6 ± 5.2% in Model I, compared with 75.9 ± 5.5% in Model II (p&lt;0.001) and 77.2 ± 7.3% in Model III (p&lt;0.01); the Model I also gave the best outcome. The prediction error of D95 for PTV60 was 0.64 ± 0.68% in Model I, compared with 2.04 ± 1.38% in Model II (p&lt;0.01) and 1.05 ± 0.96% in Model III (p=0.01); the Model I was also the best one.ConclusionsIt is significant to train the dose prediction model by exploiting deep-learning techniques with various clinical logic concepts. Increasing the height (Y direction) of training patch size can improve the dose prediction accuracy of tiny OARs and the whole body. Our dose prediction network model provides a clinically acceptable result and a training strategy for a dose prediction model. It should be helpful to build automatic Tomotherapy planning.


2021 ◽  
Author(s):  
◽  
Jennifer Glynn Vinton

<p>Avian community composition fluctuates across the landscape at different scales of space and time. These fluctuations may be modified at the broader scale of landscape and at the local scale of habitat patch. A species' ecology also influences its occurrence and abundance in the landscape. This thesis investigates the spatial and temporal distribution of the avian community in Wellington. Wellington is an interesting case study because it has a diverse range of landscapes influenced by the proximity of hills to the coast (see Appendix 3). I assess the effect of landscape classification on the richness and abundance of birds and the role of fine patch structure in shaping this distribution. My study was located within a 5-km radius of Wellington City's central business district (41 degrees 16' S, 174 degrees 46' E). I used six strip-transects divided into 400m length segments that traversed through high to lower density residential suburbs and green space inter-digitated with built habitat, and established five-minute count (FMBC) points at each segment interval along these routes for a total of 49 points. I used ArcGIS to analyse the habitat patch types in the 100-m areas surrounding the FMBC. I recorded avian species type and abundance along the strips and at the FMBC during the morning and evening. A total of 35 bird species and 10966 individuals were recorded along the strip-transects and 34 bird species and 5960 individuals at the FMBCs. House sparrow, then starling and blackbacked gull, rock pigeon, blackbird and silvereye were the most common and widely spread species. Results indicated that landscape type modified avian biodiversity with the highest number of species (S) recorded in green landscapes (n = 10, S = 15.9) and the lowest in wharf littoral (n = 2, S = 7.5) and low-density commercial sites (n = 3, S = 6.67). The diversity of the landscape within an area did not influence avian biodiversity. I found that total species abundance did not change across the landscape but that the species' ecology did influence where it occurred and its abundance in the landscape. Dietary diversity particularly influenced a species' abundance. Both season and time of day altered species richness and abundance, with lower values of richness recorded in autumn (morning period = 13.5, evening period = 10.7). I found that avian communities in the Wellington urban area were dominated by six common species but that many more species were present in much lower numbers at fewer sites. Results showed an inverse relationship between species richness and abundance - while the greater biomass (abundance) of birds concentrated at FMBC within the built commercial centre and surrounding higher density housing areas, richness increased with distance from the built centre to residential and green sites. I found no relationship between species richness and the total number of individuals present at any point, and the total biomass and abundance of birds was also independent of patch size. Neither habitat patch diversity nor average patch size influenced species diversity across the community of birds, but the effect of average patch size was less at patches between 300 and 1500 metres. The abundance of some individuals in their favoured patch type did vary in response to patch structure with the strongest relationships seen for blackbird and house sparrow. These results suggest that birds are responding to cues at the larger scale of landscape first rather than to fine patch structure within the urban setting, and therefore that landscape is a more important influence in driving bird biodiversity.</p>


2021 ◽  
Author(s):  
◽  
Jennifer Glynn Vinton

<p>Avian community composition fluctuates across the landscape at different scales of space and time. These fluctuations may be modified at the broader scale of landscape and at the local scale of habitat patch. A species' ecology also influences its occurrence and abundance in the landscape. This thesis investigates the spatial and temporal distribution of the avian community in Wellington. Wellington is an interesting case study because it has a diverse range of landscapes influenced by the proximity of hills to the coast (see Appendix 3). I assess the effect of landscape classification on the richness and abundance of birds and the role of fine patch structure in shaping this distribution. My study was located within a 5-km radius of Wellington City's central business district (41 degrees 16' S, 174 degrees 46' E). I used six strip-transects divided into 400m length segments that traversed through high to lower density residential suburbs and green space inter-digitated with built habitat, and established five-minute count (FMBC) points at each segment interval along these routes for a total of 49 points. I used ArcGIS to analyse the habitat patch types in the 100-m areas surrounding the FMBC. I recorded avian species type and abundance along the strips and at the FMBC during the morning and evening. A total of 35 bird species and 10966 individuals were recorded along the strip-transects and 34 bird species and 5960 individuals at the FMBCs. House sparrow, then starling and blackbacked gull, rock pigeon, blackbird and silvereye were the most common and widely spread species. Results indicated that landscape type modified avian biodiversity with the highest number of species (S) recorded in green landscapes (n = 10, S = 15.9) and the lowest in wharf littoral (n = 2, S = 7.5) and low-density commercial sites (n = 3, S = 6.67). The diversity of the landscape within an area did not influence avian biodiversity. I found that total species abundance did not change across the landscape but that the species' ecology did influence where it occurred and its abundance in the landscape. Dietary diversity particularly influenced a species' abundance. Both season and time of day altered species richness and abundance, with lower values of richness recorded in autumn (morning period = 13.5, evening period = 10.7). I found that avian communities in the Wellington urban area were dominated by six common species but that many more species were present in much lower numbers at fewer sites. Results showed an inverse relationship between species richness and abundance - while the greater biomass (abundance) of birds concentrated at FMBC within the built commercial centre and surrounding higher density housing areas, richness increased with distance from the built centre to residential and green sites. I found no relationship between species richness and the total number of individuals present at any point, and the total biomass and abundance of birds was also independent of patch size. Neither habitat patch diversity nor average patch size influenced species diversity across the community of birds, but the effect of average patch size was less at patches between 300 and 1500 metres. The abundance of some individuals in their favoured patch type did vary in response to patch structure with the strongest relationships seen for blackbird and house sparrow. These results suggest that birds are responding to cues at the larger scale of landscape first rather than to fine patch structure within the urban setting, and therefore that landscape is a more important influence in driving bird biodiversity.</p>


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