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Monitoring Bark Beetle Forest Damage in Central Europe. A Remote Sensing Approach Validated with Field Data
Get PDFOver the last decades, climate change has triggered an increase in the frequency of sprucebark beetle (Ips typographusL.) in Central Europe. More than 50% of forests in the Czech Republic areseriously threatened by this pest, leading to high ecological and economic losses. The exponentialincrease of bark beetle infestation hinders the implementation of costly field campaigns to prevent andmitigate its effects. Remote sensing may help to overcome such limitations as it provides frequent andspatially continuous data on vegetation condition. Using Sentinel-2 images as main input, two modelshave been developed to test the ability of this data source to map bark beetle damage and severity.All models were based on a change detection approach, and required the generation of previous forestmask and dominant species maps. The first damage mapping model was developed for 2019 and2020, and it was based on bi-temporal regressions in spruce areas to estimate forest vitality and barkbeetle damage. A second model was developed for 2020 considering all forest area, but excludingclear-cuts and completely dead areas, in order to map only changes in stands dominated by alivetrees. The three products were validated with in situ data. All the maps showed high accuracies (acc>0.80). Accuracy was higher than 0.95 and F1-score was higher than 0.88 for areas with high severity,with omission errors under 0.09 in all cases. This confirmed the ability of all the models to detectbark beetle attack at the last phases. Areas with no damage or low severity showed more complexresults. The no damage category yielded greater commission errors and relative bias (CEs=0.30-0.42,relB=0.42-0.51). The similar results obtained for 2020 leaving out clear-cuts and dead trees provedthat the proposed methods could be used to help forest managers fight bark beetle pests. These bioticdamage products based on Sentinel-2 can be set up for any location to derive regular forest vitalitymaps and inform of early damage.O
Effect of genotype and sex of piglets on their losses before weaning
Get PDFThe aim of the experiment was to analyze selected reproductive characteristics in sows and losses of piglets according to their age and to evaluate the effect of sex on survivability of piglets before weaning. The experimental observation involved 80 sows with their second litters (40 sows of genotye I and 40 sows of genotype II). The sows were mated with a boar of Danish Duroc. No significant difference was found between the evaluated genotypes of sows in numbers of live-born piglets and reared piglets, however it is evident that better results were reached by the sows of the genotype II. Also the losses of piglets per litter were lower, by 0.65 piece (P <- 0.05). In sows of the genotype I a high correlation (P <- 0.01) was confirmed between the number of live-born piglets and the number of reared piglets per litter (r = 0.750). Another correlation was found between the number of live-born piglets and their losses before weaning (r = 0.716). Similar trend was observed in the genotype II, however without significant correlation between the number of live-born piglets and the losses of piglets before weaning. The results also revealed that the piglets died mostly before the 14th day of age, while the losses of male piglets were more frequent than of female piglets. Losses of female piglets of the genotype I before the 14th day of age were 6.82 %, in the genotype II they were 3.01 %. In this period, the losses of male piglets reached 9.56 % in the genotype I and 4.49 % in the genotype II. From the 14th day to weaning the losses of female piglets counted 2.39 % vs. 0.75 %, the losses of male piglets 1.37 % vs. 2.88 %. The total losses from birth to weaning were 9.22 % vs. 3.76 % in female piglets and 10.92 % vs. 7.37 % in male piglets.O
Effects of a Trench as a Moisture Harvesting Structure on the Biomass Production and Growth of Trees Planted to Restore Degraded Land, Southern Ethiopia
Get PDFKnowledge about the biomass productivity of trees planted in a rainwater harvesting structure, i.e., a trench (T), relative to a normal pit (P) on degraded land is scarce. The objective of this research paper is to compare the effect of T with P on the growth and biomass production of the Acacia saligna and Casuarina equisetifolia which were planted on degraded land. All the individual stems of both species in the T and P, their diameters at breast height (DBH) and heights in 2016 and 2020 were measured. Species-specific allometric equations were used to quantify the biomass production of the studied species. The t-tests were used for data analysis; both A. saligna and C. equisetifolia individuals planted in the T had higher DBH and height increment as compared with A. saligna and C. equisetifolia that were planted and grown in a P. The results also revealed significant differences on the mean DBH and height of A. saligna and C. equisetifolia planted in a T and P (p < 0.05). Between 2016 and 2020, the total biomass (TB) of A. saligna planted in a T and in a P increased significantly (p < 0.05) on average by 25.5 kg/tree and 7.7 kg/tree, respectively (p < 0.05). Similarly, the mean TB values of the C. equisetifolia planted in a T and a P between 2016 and 2020 increased significantly (p < 0.05) by 28.9 kg/tree and 13.1 kg/tree, respectively. Finally, establishing trenches to restore degraded lands was shown to facilitate growth and biomass production of planted species on degraded land.O
Socioeconomic Impact of Mining in the Atiwa Forest Reserve of Ghana on Fringe Communities and the Achievement of SDGs: Analysis from the Residents' Perspective
Get PDFThe Atiwa forest reserve of Ghana sits upon roughly 150 million tons of bauxite. The Government has decided to mine and use the proceeds for national infrastructure development programs. This article examines the impact of mining on the residents' livelihoods and the achievement of the SDGs from the perspective of the residents. A questionnaire was administered to 197 respondents. Per the findings, the residents around the forest reserve do not consent to the proposed mining project. Although they give credit to its possible job creation opportunities, the irreplaceable nature of the forest reserve urges them not to consent to the initiative. They depend on the rivers and streams for their livelihoods, and the affected districts are also among Ghana's major cocoa producers. These farmers depend on these water bodies for irrigation. It is necessary to preserve them in order to sustain the production of these cash crops that make a direct contribution to the country's GDP.O
Organic Food Needs More Land and Direct Energy to Be Produced Compared to Food from Conventional Farming: Empirical Evidence from the Czech Republic
Get PDFThis study investigated direct energy consumption and land performance under two different methods of farming-organic and conventional. The aim of our study was to examine the performance of farmers in the Czech Republic and identify the differences between organic and conventional farming regarding food safety and direct energy consumption. Based on the data from the Farm Accountancy Data Network of the EU, we measured the performance of both organic and conventional farmers in terms of product per unit of land and direct energy consumption per unit of product regarding the natural condition of the farm localization. Our findings show that organic farms produce lower output with less direct energy per unit of land; however, they need more direct energy for one unit of production. We found that a product from organic agriculture consumes 1.7-fold greater direct energy than a conventional product. The worse the natural conditions for farming, the broader the difference between organic and conventional regimes regarding their performance and energy consumption. Our conclusions may help shape agricultural policy in the Czech Republic, where organic farming is receiving systematic political support, leading to an increase in the proportion of organically farmed arable land.O
The Effects of Potassium Silicate as a Component of Nutrient Medium for Selected in Vitro Cultures of Prunus and Corylus Genera
Get PDFEven though silicon is frequent compound in soil, its use in plant nutrient media is rare. Based on known physiological role and up to now performed studies it seems that silicon has a good potential to improve growth characteristics of in vitro cultivated plants. Before practical application, however, it is always necessary to assess the optimal conditions of application with regard to the fact that plant reactions to different chemicals added to nutritional media can vary on the species or even cultivar level. The presented study evaluate effects of potassium silicate used in in vitro cultivation media on growth parameters of Prunus persica x Prunus davidiana 'Cadaman,'Prunus x amygdalopersica 'GF 677'and Corylus avellana 'Tonda di Giffoni'genotypes, which are frequently subject of commercial in vitro multiplication. In fact, four different concentrations of potassium silicate was added to the multiplication media, control medium was left silicon-free. Three different characteristics were observed during cultivation - number of new shoots per explant, weight of a new plant and length of new shoots, from which number of new shoots per explant was considered the most important factor. In all cases a positive effects of potassium silicate on the condition and other growth parameters of treated cultures were observed. In 'Cadaman'culture significant growth changes appeared on media with 20 mg.l-1 potassium silicate, which can be recommended for future applications. For 'GF 677'the best results were obtained on media with 2 mg.l-1 which can be recommended for improving condition and number of shoots on new plants. For hazelnut genotype 'Tonda di Giffoni'best results were obtained on media with 10 mg.l-1 of potassium silicate, but also use of 5 mg.l-1 of potassium silicate significantly improved growth parameters. Generally, presented study provides important and practically useful insights into the practical use of silicon in cultivation media designated for commercial in vitro micropropagation.O
The State of the Art of Use of the Concept of Ecosystem Services within Spatial Plans in the Czech Republic
Get PDFAlthough the use and management of ecosystem services (ES) resources and the promotionof their provision are a standard and necessary part of spatial planning tools and documents, a directimplementation of this concept is exceptional. Researchers and entire projects have so far focusedmainly on identification of ecosystem services and their resources in urban environment, or on theanalysis of their occurrence in spatial planning documents. That was the goal of our research as well.Spatial planning documents, systematically and methodically re-defined using ecosystem services,are what is still lacking. Our article presents the results of the analysis of the use of ecosystem servicesin spatial plans of five cities, regional centers in the Czech Republic. We used a text evaluationmethodology focused on the explicit and implicit expression of ecosystem services. We analyzed theoverall approach to the creation of spatial plans. In addition to the spatial plans, we also analyzedtheir assignments (SPA). We found that the current spatial planning methodology does not work withthe ecosystem services approach (ESA) systemically. It focuses mainly on ES resources and implicitlyenvisages their provision. SPAs are a more flexible and effective tool for enforcing ESA in spatialplanning than the lengthy legislative process. However, this presupposes greater knowledge of SPAamong the public and decision makers.O
Epigeic spiders from lowland oak woodlands in the south Moravia region (Czech Republic)
Get PDFThis paper presents spider faunistics from abandoned coppice oak forest stands located along the South Moravia region. Spiders were collected from May to July 2012 by pitfall trapping at eight different localities. We collected 1945 adult spiders representing 20 families, 53 genera, and 90 species. More than one-third of all the species are known to be xerothermophilous with ecological restrictions to open and partly shaded habitats such as forest-steppe and sparse forests which belong to endangered habitats along central Europe. The most abundant species were Pardosa alacris, P. lugubris and Arctosa lutetiana from the family Lycosidae. In the surveyed area, 24 species were found listed in the Red List of Threatened Species in the Czech Republic (CR - 1 species, EN - 2 species, VU - 15 species, LC - 6 species). In general, we discovered a substantially diversified spider community with a large presence of rare and endangered species characteristic for open and xeric habitats.O
Evironmental Tax. Are Vehicle Registers in the EU Prepared?
Get PDFThe market system is unavailable to reflect negative externalities, caused by road motor trafic, in the realized prices. For that purpose, it would be appropriate to implement a general environmental road tax in the European Union member states. The question is whether the national registers of vehicles are prepared for such a change. Whether this is the case at present, may be found out by means of analyses of the available national registers. The next step is synthetic: the data must be subsequently completed on the basis of the knowledge of needs of currently existing systems of road motor vehicles taxation. In the end, the identified results may be supplemented with the known data published by international institutions. The results of the research show that the present systems of road motor vehicles taxation are utterly different and distortive. Only 12 countries of the European Union have registers which were clearly identified as prepared for the application of the environmental tax. Registers of the remaining countries do not contain one or more data that are necessary for the implementation of the environmental tax. For this reason we may assume that regardless of other determinants, environmental road tax shall not be introduced throughout the European Union in the foreseeable future.O
Quality of Word Vectors and Its Impact on Named Entity Recognition in Czech
Get PDFNamed Entity Recognition (NER) focuses on finding named entities in text and classifying them into one of the entity types. Modern state-of-the-art NER approaches avoid using hand-crafted features and rely on feature-inferring neural network systems based on word embeddings. The paper analyzes the impact of different aspects related to word embeddings on the process and results of the named entity recognition task in Czech, which has not been investigated so far. Various aspects of word vectors preparation were experimentally examined to draw useful conclusions. The suitable settings in different steps were determined, including the used corpus, number of word vectors dimensions, used text preprocessing techniques, context window size, number of training epochs, and word vectors inferring algorithms and their specific parameters. The paper demonstrates that focusing on the process of word vectors preparation can bring a significant improvement for NER in Czech even without using additional language independent and dependent resources.O