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Context
Pattern-based spatial analysis provides methods to describe and quantitatively compare spatial patterns for categorical raster datasets. It allows for spatial search, change detection, and clustering of areas with similar patterns.
ObjectivesWe developed an R package motif as a set of open-source tools for pattern-based spatial analysis.
MethodsThis package provides most of the functionality of existing software (except spatial segmentation), but also extends the existing ideas through support for multi-layer raster datasets. It accepts larger-than-RAM datasets and works across all of the major operating systems.
ResultsIn this study, we describe the software design of the tool, its capabilities, and present four case studies. They include calculation of spatial signatures based on land cover data for regular and irregular areas, search for regions with similar patterns of geomorphons, detection of changes in land cover patterns, and clustering of areas with similar spatial patterns of land cover and landforms.
ConclusionsThe methods implemented in motif should be useful in a wide range of applications, including land management, sustainable development, environmental protection, forest cover change and urban growth monitoring, and agriculture expansion studies. The motif package homepage is https://nowosad.github.io/motif.
相似文献2.
The possibility of application of agglomerate elastomers (EPP) as media for biological bed in aquaculture 
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下载免费PDF全文 Mateusz Sikora Joanna Nowosad Mateusz Biegaj Dariusz Kucharczyk Marcin Dębowski 《Aquaculture Research》2018,49(9):2988-2994
The aim of the study was to determine the possibility of experimental media (agglomerate elastomers EPP) application as biological media bed, which serves the purpose of water purification in recirculating aquaculture systems (RAS). RAS enables mass‐production of fish in small volume of water in a limited area. This involves the possibility of multiple usage of water during culture. However, for that purpose of maintaining proper physico‐chemical parameters, water purification from products of metabolism, especially toxic nitrogen compounds, is required. One of the simplest and most effective ways to achieve it is combining application of two types of water filtration: mechanical and biological. It is needed to study new media for biological bed with proper filling is able to purify water from toxic nitrogen compounds. 相似文献
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Effect of temperature on growth and survival of maraena whitefish Coregonus maraena (Bloch 1779) larvae in controlled conditions 下载免费PDF全文
下载免费PDF全文 Roman Sebesta Dariusz Kucharczyk Joanna Nowosad Mateusz Sikora Vlastimil Stejskal 《Aquaculture Research》2018,49(9):3151-3157
This 28‐day study investigated the effect of three rearing temperatures, 11, 15 and 19°C, on survival and growth of maraena whitefish fry in a recirculating aquaculture system. Three groups of larvae in three repetitions were reared in recirculating system. Each group comprised 200 larvae. Feeding level was fixed at 500–700 Artemia sp. metanauplii per fish per day. Larvae were fed fresh live brine shrimp at 10 ml/tank every 3 hr. Significantly higher body weight (p = 0.00), total length (p = 0.00), larval yield (p = 0.00) and condition factor (p = 0.00) were obtained at 19°C compared to 15 and 11°C, as well as at 15°C compared to 11°C. Significantly higher survival (p = 0.00) was observed in larvae reared at 11 and 15°C compare to 19°C and no significant differences were observed between 11°C compared to 15°C. No significant differences in size heterogeneity among treatments were found (p = 0.46). In larviculture, the optimal assessed temperature for growth of maraena whitefish was 19°C, with highest survival observed at 11°C, at the end of this 28 days trial. The findings in this study apply to the particular study location and may not be applicable more broadly. 相似文献
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Joanna Nowosad Daniel Żarski Maria Biłas Katarzyna Dryl Sławomir Krejszeff Dariusz Kucharczyk 《Aquaculture International》2013,21(3):629-637
This paper presents the first data on ammonia excretion by fed and starved juvenile common tench. The aim of the study was to determine the amount of ammonia excretion by juvenile common tench Tinca tinca (L.), fed with a commercial feed under intensive rearing conditions. Rearing was conducted for a period of 4 weeks at a water temperature of 27 °C. On the test day, the amounts of ammonia excreted by starved fish (over 12 h: control group) and fish fed with a morning feed dose (3 % of biomass: experimental group) were determined at 1, 3, 5, 7, 9 and 11 h after feeding. Ammonia excretion measurements were taken in 7-day intervals. Despite the increased growth rate in successive weeks of experiment, the amount of ammonia excreted by the fish was always at a similar level within the control (maximum 0.26 mg g?1) and the experimental group (maximum 0.39 mg g?1). This paper presents for the first time reliable amount of ammonia excreted by fed and starved juvenile common tench. The obtained results may also increase the effectiveness of intensive rearing procedures (taking into account stocking density and feeding regime) and allow to design the most effective biofiltration capacity of recirculating aquaculture systems for the commercial production of this species. 相似文献
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K. Palińska-Żarska D. Żarski S. Krejszeff J. Nowosad M. Biłas K. Trejchel D. Kucharczyk 《Aquaculture International》2014,22(1):13-27
The study concerns investigation of early larval development of burbot, Lota lota. As part of a two-year study, the first 15 days (until the end of yolk sac resorption) of burbot larvae development under controlled conditions were examined. The aim of the study was to observe the moment of swim bladder inflation and the behavioural aspects of this process, as well as the analysis of yolk and oil droplet resorption and the beginning of exogenous nutrition. It was observed that larvae began to inflate their swim bladder on the 3rd day post-hatch. On 5 DPH, none of the larvae without an inflated bladder was able to swim up the distance separating it (10 cm) from the water surface. Since 9 DPH, 50 % of larvae started exogenous feeding, and the absence of yolk was observed on 13 DPH and oil droplet on 14 DPH, while on 15 DPH, 100 % of feeding larvae were observed. The presented results indicate that the analyzed period is critical for burbot, and it is characterized by a high mortality rate (over 60 %). Additionally, the results suggest that, under controlled conditions, the latest moment when burbot larvae should be given exogenous food is 9–10 DPH and until the moment of the swim bladder inflation, larvae should be kept in tanks with a low water depth (up to 10 cm). The data presented in this study could have a significant influence on the efficiency of larvae rearing, both for aquaculture and for restocking purposes. 相似文献
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Jan Bocianowski Kamila Nowosad Piotr Szulc 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2019,69(1):75-81
The objective of this study was to assess soil tillage methods by years interaction for harvest index (HI) of maize (Zea mays L.) grown in West Poland by the additive main effects and multiplicative interaction model. The study comprised four soil tillage methods, analysed in 12 years through field trials arranged in a randomised complete block design, with four replicates. HI of the tested soil tillage methods varied from 0.354 to 0.692 throughout the 12 years, with an average of 0.530. In the variance analysis, 57.06% of the total harvest index variation was explained by years, 2.39% by differences between soil tillage methods, and 8.71% by soil tillage methods by years interaction. HI is highly influenced by year factors. The method of reduced conventional tillage [autumn shallow ploughing (15 cm), cultivator with string roller in spring] was the most stable (additive main effects and multiplicative interaction stability value, ASV=0.410) for the HI values among studied soil tillage methods. This result confirms the opinion on the possibility of shallowing autumn ploughing in the cultivation of maize for grain. 相似文献
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A 11-year survey on helminth intestinal infection of horses was done in seven provinces of southern Poland. 21,641 faecal samples were collected from horses of different age, sex, breed and management system originating from 84 farms. Age was the major factor influencing the cyathostome egg excretion, the maximum being observed in yearlings and second year horses. Parascaris was found mostly in foals and yearlings. The main factor for Anoplocephala was the access to pasture. The level of cyathostome egg shedding (EPG) could be related to sex (geldings had higher values of EPG), breed (Thoroughbred had higher EPG than other breeds), and type of farm (large farms had higher EPG than others). The change during the survey of anthelmintic treatment (from benzimidazole or pyrantel embonate to avermectins) was associated with lower cyathostome EPG, and this was probably due to partial resistance to benzimidazole. The seasonality of egg shedding (lowest from November to January included) was due to management (leaving the pasture to stable, anthelmintic treatment in October). The influence of climate on EPG was significant but small, annual rainfalls and average temperature being associated negatively and positively, respectively, with high cyathostome EPG. 相似文献
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