National Repository of Grey Literature 6 records found  Search took 0.01 seconds. 
Establishment of agroforestry systems on agricultural land
Krčmářová, Jana ; Szabó, Péter ; Kala, Lukáš ; Doležalová, H. ; Snášelová, M. ; Králík, T. ; Jobbiková, J. ; Vávrová, K. ; Weger, J. ; Ehrenbergerová, L. ; Martiník, A. ; Chládová, A. ; Kotrba, R. ; Houška, J. ; Lojka, B.
The current intensive and industrial agriculture in the Czech Republic has many nega-tive impacts on the environment. Agroforestry, i.e. growing trees on agricultural land while maintaining agricultural production, can minimize these negative effects. Tree species grown in agroforestry systems (AFS) fulfil a productive function and at the same time provide important ecosystem services. The aim of this methodology is to define agroforestry, characterize individual types of AFS and estimate their extent in the Czech Republic. The aim is to provide background materials on the basis of which it is possible to establish agroforestry systems on agricultural land. The result is a clear definition, classification and characterization of different AFS in Czechia. Furthermore, their extension is estimated, and their historical roots explained. The methodology of establishment of AFS proposes a suitable design, list of suitable of woody species and describes the procedure of correct tree planting and management. An important part of the methodology is the analysis of the legislative environment for tree planting on agri-cultural land, economic evaluation of AFS and also the selection of suitable subsidy titles for such establishment. Last but not least, the methodology summarizes the existing capacity building and education in agroforestry in the Czech Republic.
Impact of agroforestry on dragonflies diversity
Kajzrová, Soňa ; Lojka, Bohdan (advisor)
Tropical rain forests around the world suffer from deforestation, which is caused mainly by small-scale farmers. These farmers largely employ slash-and-burn methods to clear the land for agricultural settlement. Agroforestry systems are widely found in the humid tropics, where they could have great potential to increase the productivity of farming systems and sustain continuous crop production and they are also supposed to conserve biodiversity. As a group of freshwater invertebrates, dragonflies (Odonata) are commonly used as ecological indicators of freshwater ecosystems. The main objective of the study is to assess the impact of land use changes on dragonflies (Odonata) species richness and diversity, namely primary and secondary forest, cocoa agroforest and slash-and-burn agriculture in the Tropical Africa. We hypothesize, that the species richness and diversity of dragonflies decrease with disturbance of the ecosystems, along the land-use changes gradient.
Mophological and molecular diversity of a tropical tree species Guazuma crinita in the Peruvian Amazon
Tuisima Coral, Lady Laura ; Lojka, Bohdan (advisor) ; Helena, Helena (referee)
Fast growing tree species Guazuma crinita (Malvaceae) was selected as a priority species for domestication in the Peruvian Amazon due its important contribution to the livelihood of local farmers. Its domestication process is still in an early age as for many tropical tree species little is known about its genetic variability and we dont know anything about the impact of domestication on its genetic resources. The main objective of this research was to assess the genetic variability of G. crinita within and among populations in the Peruvian Amazon by the use of morphological (wood physical traits) and molecular (ISSR and AFLP) markers. Wood physical properties among six G. crinita provenances were evaluated. Wood samples were drilled from the base middle and top of the stem of 12 randomly selected eight-years-old trees for determination of wood measurement. Pearson correlations between physical properties were also determined. All wood physical properties except green density differed significantly among provenances. We also found statistically significant variation due to stem level position. The moderately dense wood and the coefficient of anisotropy (1.6) suggested that G. crinita has stable wood; they represent important advantages in terms of costs for transport and transformation process. The results suggested potential to select provenances with desirable wood properties for further breeding and domestication. Due to the variation found even in limited tree samples it is recommended further analysis with more extensive number of samples from different provenances and planting zones. This research presents the first assessment of genetic variability based on inter-simple sequence repeat (ISSR) markers for 44 G. crinita genotypes from a clonal garden multiplication established in the Peruvian Amazon Research Institute (IIAP) in Ucayali region. Ten ISSR primers amplified a total of 65 bands of which 61 were polymorphic (93.8%). The range of DNA amplification varied from 260 to 2200 bp. Among the provenances overall genetic differentiation (Gst) was 0.03 indicating 97% of genetic diversity within provenances. Gene flow (Nm) was 12.9 alleles per generation. Cluster analysis was not related with geographic origin suggesting a common gene pool which was supported by calculation of weak positive correlation was found between genetic and geographic distance. With the use of AFLP markers an insight on how domestication process does impact G. crinita genetic resources is also reported on this research work. I was able to generate fingerprint for 58 leaf samples representing eight provenances and three population types, 19 from a natural regenerated population 15 cultivated in home garden nursery and 24 from a collection of genotypes considered as semi-domesticated population. Seven selective AFLP primer combinations were used. A total of 171 fragments were amplified with 99.42% of polymorphism at species level. Each type of population generated fragments with 72.51% 49.12% and 54.39% of polymorphic fragments respectively. Neis genetic diversity and Shannon index information were found to be higher in the population of natural regeneration compared to overall semi-domesticated population (He = 0.10 and 0.9; I = 0.19 and 0.16 respectively). The analysis of molecular variation (AMOVA) showed higher variation within provenances rather than among (84% and 4% respectively). UPGMA clusters analysis and PCoA did not showed correspondence between genetic and geographic distance in addition their correlation was not significant. There was a significant genetic differentiation among types of population suggesting slight genetic bottleneck in semi-domesticated populations yet with relatively high levels of genetic variation. In situ conservation for populations with high levels of genetic diversity was recommended. In addition proper management of natural regeneration and ex situ genotype collections might be a good conservation strategy to maintain G. crinita genetic resources. The use of morphological (wood physical traits) and molecular markers were successful to reveal genetic variability of G. crinita and they could be used for other tropical tree species. For further researches it is emphasis to extent the number of samples and geographic scale.
Agroforestry Systems in Czech Republic
Zelba, Ondřej ; Lojka, Bohdan (advisor) ; Antonín, Antonín (referee)
Temperate agroforestry has been described and categorized several times and there are numerous definitions in use. Even though several agroforestry practices have been traditionally used in Czech Republic, any inventory of farms or plots where agroforestry is currently practiced is still missing. This study aimed to find a practical and relatively easy method to identify agroforestry systems on farmland. Firstly, several European surveys such as Land Use and Cover Area Frame Survey (LUCAS) and Corine Land Cover (CLC) were examined to evaluate their applicability in inventory of agroforestry, and several methods of identifying trees in agricultural land blocks were reviewed. The thesis tried out a method that uses Corine Land Cover data in ArcGIS software to identify out patches of land that fall into the annual crops with permanent crops category. It then found agricultural land blocks with trees in those polygons. In the last part of the study, farmers owning plots in the agroforestry field blocks were located in the land registry and a questionnaire was sent out to them regarding the origin, function, and use of the trees in the agricultural blocks to collect information about the land-use systems. In total 3,071 hectares of field blocks were identified to fit the agroforestry conditions, mostly in the South Moravia region. Most of the found areas are in proximity of towns Velké Pavlovice, Louka u Ostrohu, Strážnice na Moravě, Moravský Žižkov, and Šakvice. The areas found there have many small plots that are each owned by a different owner, which creates a very heterogenous landscape. The area is well known for its fruit orchards and the questionnaire answers confirm that the area is indeed suitable for trees like apricots and cherries. The answers have also shown that the agricultural production directly neighboring with the trees used to be much more varied in the past. The thesis also reviewed legislative options for the support of agroforestry and suggested an improved ruleset to determine if a land-use system should be supported by subsidies for agroforestry systems.
Morphological and genetic diversity of camu-camu (Myrciaria dubia, Mc Vaugh) in Peruvian Amazon
Šmíd, Jan ; Lojka, Bohdan (advisor) ; Petra, Petra (referee)
Camu-camu (Myrciaria dubia, McVaugh) is currently one of the most important fruit species that is grown in the Peruvian Amazon, as well as in Brazil, Colombia or Bolivia. Larger plantations were established only in the last two decades and a substantial part of the production is still obtained by collecting fruits from the wild. Domestication of the species is still at its very beginning; most of the farmers cultivate the plants without any breeding or just after simple selection. The aim of this study was to characterize the morphological and genetic variability of cultivated and natural populations of camu-camu in the Peruvian Amazon and also to compare the variability among and within these populations. In total we have sampled 13 populations; 10 wild populations in Iquitos region, three cultivated populations in Pucallpa in Peruvian Amazon. For genetic analysis, the leaf tissue samples were collected from ten individuals from each population (n=126), and for morphological data were collected from five trees of each population (n=65). To assess the genetic diversity, we used seven microsatellite primers that were developed from available DNA sequences. Using various genetic softwares, major indexes of variability were detected and dendrograms of relatedness of populations and individuals were created. The statistical analysis did not reveal statistically significant differences for most of the morphological descriptors, except for the fruit parameters. Surprisingly, the trees from wild populations had higher fruit and pulp weight and their fruits contained less seeds compared to cultivated populations. The observed heterozygosity was 0.347 and 0.404; expected 0.516 and 0.506; inbreeding coefficient was 0.328 and 0.200 for wild and cultivated populations, respectively. Wild populations could be divided according to the dendrogram into two completely different groups. In cultivated populations, their approximate origin was determined. All the results indicated a high genetic variability but also a high degree of inbreeding. This can be explained by isolation of the populations from each other or low number of individuals in the population. This high level of diversity can be explored for selection of superior individuals and further possibilities of breeding.
Genetic diversity of baobab (&-lt;i&-gt;Adansonia digitata&-lt;/i&-gt; L.) along an elevation transect in Kenya
Chládová, Anna ; Lojka, Bohdan (advisor) ; Petra, Petra (referee)
@Adansonia digitata@L. (Malvaceae) is a huge multipurpose tree of the savannahs of sub-Saharan Africa with high economic potential for local communities. The edible fruits and leaves are known for their high nutritional values and can be used fresh or processed. However, a high intra-specific variability regarding morphology, genetics and nutritional content of baobab and its products is documented for several African regions, while data for Kenya is largely lacking. This study aimed at documenting the genetic and morphological variability of baobab accessions in Kenya and at checking the presence of the newly described diploid baobab species @Adansonia kilima@. Samples were collected from 204 baobab trees from seven populations defined by geographical distance in South-eastern and Coastal Kenya at altitudes of 6-1,058 m asl. Leaf or bark samples for genetic diversity assessment were collected from all 204 trees, while leaves only from 65 and fruits from 76 trees (all in inland locations) for morphological analyses based on the publication Descriptors for Baobab. Nine microsatellite loci were used to assess genetic variation and results analysed with specific software because of the tetraploid nature of baobab. Overall genetic diversity was high and all loci were polymorphic. The mean gene diversity was 0.803 and observed heterozygosity was 0.907. Analysis of molecular variance (AMOVA) revealed low variation among populations (12.4%) and high variation within populations (87.6%). Bayesian clustering and Principal Coordinate Analysis divided the accessions into two clusters, one with only inland and one with coastal accessions. Although the presence of @Adansonia kilima@ was previously postulated for Kenya, flow cytometry did not detect any among the analysed samples as only tetraploids were observed. Regarding morphological characteristics, no differences among the fruit accession from inland populations were found (no fruits were collected in coastal areas). Leaf morphological data showed significant differences between inland and coastal populations with longest leaflets and leaf petioles in accession from the Coast, thus confirming the results obtained for genetic analysis. This study contributes to the overall knowledge of the genetic diversity of baobab in Kenya and can contribute to the development of germplasm conservation strategies and domestication programs for baobab.

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