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Productivity benchmarks for community-based genetic improvement of Abergelle, Central Highland and Woyto-Guji indigenous goat breeds in Ethiopia Texto completo
2019
Jembere, Temergen | Haile, Aynalem | Dessie, Tadelle | Kebede, Kefelegn | Okeyo Mwai, Ally | Rischkowsky, Barbara A.
Productivity benchmarks for community-based genetic improvement of Abergelle, Central Highland and Woyto-Guji indigenous goat breeds in Ethiopia Texto completo
2019
Jembere, Temesgen | Haile, Aynalem | Dessie, Tadelle | Kebede, Kefelegn | Mwai, Ally Okeyo | Rischkowsky, Barbara
Assessments of production parameters and flock productivity were made in three indigenous goat breeds of Ethiopia. The goat breeds included Abergelle (AB), Central Highland (CH) and Woyto-Guji (WG). Objectives of this work were to estimate production parameters including three month weight (3mw), kidding intervals (KI) and litter size (LSB) at birth for the breeds and to assess their productivity at flock level that could be used as benchmark for evaluation of genetic progress to be realized. As AB is used for milk production, adjustment was made to their 3mw. The overall mean of 3mw (kg) were 7.44, 10.96 and 9.38 for AB, CH and WG goat breeds, respectively. Generally, wet season, male sex and single birth resulted in higher 3mw for three breeds. The overall means of KI were 362, 268 and 309 days for the breeds in respective order. The overall means of the LSB for the goat breeds, in respective order, were 1.03, 1.40 and 1.09 per doe per parturition. The flock productivity ranged from 0.27 to 0.53. Higher LSB, survival to three months (S3M), 3mw and number of parturition per year (N) resulted in higher flock productivity. CH goat breed had the highest flock productivity. The parameters estimated in this paper could be used as benchmarks for the designed CBBP of goats in the studied localities.
Mostrar más [+] Menos [-]Growth performance of Boer goats and their F1 and F2 crosses and backcrosses with Central Highland goats in Ethiopia Texto completo
2019
Mustefa, A. | Gizaw, Solomon | Banerjee, S. | Abebe, A. | Taye, M. | Areaya, A. | Besufekad, S.
This study aims to investigate genetic and non-genetic factors affecting growth performance of Boer goats and their crosses with Central Highland goats (CHG) reared on-station at Ataye site of Debre-Birhan Agricultural Research Center in Ethiopia. A total of 512 kids of Boer (B), F1 (B X CHG) and F2(a) (F1 X F1) crossbreds and backcrosses F2(b) (B X F1) born from 381 kiddings recorded between 2012 and 2017 were used for the analysis of body weight at birth, at weaning, at six-month, at yearling and body weight gain to weaning, weaning to six-month and six-month to yearling. The overall least-squares means across genotypes for birth weight (BW), weaning weight (WW), six-month weight (6MW), yearling weight (YW) were 3.05±0.06 kg, 10.9±0.36 kg, 12.5±0.51 kg and 18.3±0.88 kg, respectively for Boer and 2.62±0.04 kg, 8.80±0.22 kg, 11.2±0.31 kg and 16.7±0.48 kg, respectively for F1. Similarly, the BW and WW of the F2(a) and F2(b) were (2.50±0.13 kg and 8.37±0.74 kg) and (2.94±0.15 kg and 9.80±0.75 kg) respectively. The overall least-squares means across breed groups for daily weight gain to weaning, weaning to six-month and six-month to yearling were 83.9±3.76 g, 25.6±3.29 g and 27.6±2.69 g, respectively for Boer, and 67.0±2.26 g, 31.5±2.00 g and 28.4±1.46 g, respectively for F1. Similarly, daily weight gains to weaning was 67.7±7.66 g and 78.7±7.74 g for the F2(a) and F2(b) respectively. Sex, type of birth, year of birth and season of birth affected the studied traits, while, doe parity has no significant effect except at the later age weight gain. In conclusion, the overall growth performances of all the studied genotypes were below expectations which indicates their sub-optimal adaptability to the study area. In addition to the genotype, the non-genetic factors affect the growth performance, so improvement in growth performances is possible by minimizing environmental effects.
Mostrar más [+] Menos [-]Development of young stands after different intensity regeneration fellings Texto completo
2019
Klavins, I., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Kalvite, Z., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Libiete, Z., Latvian State Forest Research Inst. Silava, Salaspils (Latvia)
The share of the renewable resources used continues to grow due to environmental, economic and political reasons. Consequently, intensification of forest management is on-going and expected to continue in the future. Logging residues, such as treetops, branches and stumps, are a significant renewable energy source. Since the logging residues are noticeably richer in nutrients than conventionally harvested stems, there is a concern related to the negative impact of intensified harvesting on the ecosystems, productivity of the sites and sustainability of forestry in general. To evaluate the impact, this study has compared different intensity harvesting effect on the next rotation young stand productivity in eight sites in Latvia. In a nutrient-rich site, the productivity of Norway spruce was higher in the whole-tree harvest (WTH) subplot comparing to stem-only harvesting (SOH) subplot three years after the planting. Productivity of Scots pine in oligotrophic conditions was observed to be higher in SOH subplot comparing to WTH subplot two and three years after planting. Furthermore, in a site on a mineral soil relatively richer in nutrients no significant differences were observed. Comparing WTH to whole tree harvest + stump biomass (SB) extraction subplots, the productivity of Norway spruce was higher in WTH four to five years after the planting; in a mixed stand of Norway spruce and black alder no productivity differences of spruce were detected, but productivity of black alder was higher in WTH+SB subplot five years after the planting; in black alder stands a significantly higher productivity was observed in WTH subplot four and five years after the planting.
Mostrar más [+] Menos [-]Macrostructure and density of pine and spruce wood on fallow lands on North-West of Russia Texto completo
2019
Danilov, D., Leningrad Scientific Research Inst. of Agriculture ''Belogorka'', Belogorka village, Gatchina district, Leningrad region (Russian Federation);Saint-Petersburg State Forest Technical Univ. named after S.M. Kirov (Russian Federation) | Janusz, S., Saint-Petersburg State Forest Technical Univ. named after S.M. Kirov (Russian Federation)
Growing spruce and pine wood on land being out of active agricultural use is important for many European regions. The study of the qualitative characteristics of coniferous wood makes it possible to predict target indicators of the obtained raw materials. The influence of xylem structural elements on the density of spruce pine wood on the postagrogenic lands of the boreal zone of Russia was studied. The objects of the research were spruce-pine stands growing on old arable land in the Gatchina district of the Leningrad region. Depending on the share of the species, various anatomical indicators of the macro-structure of wood influence the formation of the spruce and pine wood density. For the spruce part of the forest stand, the width of the annual increase makes a greater contribution to the formation of indicators of wood density. For the pine part of the forest stand the density of the wood correlates with the proportion of late xylem. With a different proportion of the species, the influence of macro-structural elements on the density of wood changes. Conducted analysis of variance showed a significant effect of the forest stand composition on the anatomical macro-structure of spruce and pinewood.
Mostrar más [+] Menos [-]Evaluation of potential impact of soil scarification pattern on trees’ damages in future commercial thinning Texto completo
2019
Kaleja, S., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Spalva, G., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Lazdins, A., Latvian State Forest Research Inst. Silava, Salaspils (Latvia)
The aim of the study is to analyse the empirical data collected in 2017, explaining the distribution of mechanically damaged trees left after the commercial thinning, in order to characterize the potential impact of the change of soil scarification working direction on the intensity of damage to the trees left in the felling during the following pre-commercial thinning. The study found that extraction or leaving logging residues in the felling area did not significantly affect the productivity of the soil scarification, but in areas where logging residues were extracted, the depth of the furrows increased significantly, implying a better quality of soil preparation in these areas. The study did not identify the correlation between strip-road patterns (combined or uncoupled ends) with damage intensity, but the research hypothesis was confirmed that the number and proportion of damaged trees is significantly increasing at the ends of the technological corridors. A bigger increase of proportion of damaged trees at the end of strip-roads was found in pine stands. When modelling the effect of soil preparation and logging design on the proportion of damaged trees, species specific parameters should be used – the proportion of damaged trees at the corridor ends in pine stands is 68%, in spruce stands – 45% compared to the rest of the stand. The rest of the stand can be characterized by production statistics or by the results of the study – the average proportion of damaged trees in spruce stands is 4.9% and in pine stands – 0.8% of the remaining trees.
Mostrar más [+] Menos [-]Transformation of the organic matter of forest and postagrogenic soils of the boreal zone of Russia Texto completo
2019
Vaiman, A., Leningrad Scientific Research Inst. of Agriculture ''Belogorka'', Belogorka village, Gatchina district, Leningrad region (Russian Federation);Saint-Petersburg State Forest Technical Univ. named after S.M. Kirov (Russian Federation) | Danilov, D., Leningrad Scientific Research Inst. of Agriculture ''Belogorka'', Belogorka village, Gatchina district, Leningrad region (Russian Federation);Saint-Petersburg State Forest Technical Univ. named after S.M. Kirov (Russian Federation) | Zhigunov, A., Leningrad Scientific Research Inst. of Agriculture ''Belogorka'', Belogorka village, Gatchina district, Leningrad region (Russian Federation);Saint-Petersburg State Forest Technical Univ. named after S.M. Kirov (Russian Federation)
The purpose of the study was to compare forest and postagrogenic soils by parameters such as carbon content in organic matter and total nitrogen to predict the fertility state of lands that are at the stage of restoration of woody vegetation. Areas with similar soil formation conditions were selected on the postagrogenic and forested lands having mature forest stands related with such types of forest: Myrtillosum forest, Oxalidosum and Herbosa-Composita forest, and also areas under the soil complexes of postagrogenic fallow lands. A number of physico-chemical indicators for the soil were assessed according to the methods generally accepted in soil science: the particle size distribution, the bulk density and the thickness of the pedogenic horizons were determined. An analysis of the carbon stocks in organic matter (Corg) and nitrogen (Ntotal) in the genetic horizons of the soils of myrtillosum, Oxalidosum and Herbosa-Composita forest types shows an increase in the content of organic matter and total nitrogen from Myrtillosum to Herbosa-Composita forest type. A comparative analysis of the physical and agrochemical state of postagrogenic and forest soils showed that, despite the previous anthropogenic impact, the agroland horizon retains a high content of organic matter and total nitrogen. The properties of postagrogenic soils in the studied areas are not deteriorated, and the transformation towards the natural forest soils of the region is not observed, despite the long period of fallowing.
Mostrar más [+] Menos [-]Forest management challenges and opportunities of two-layered birch and spruce stands in Latvia Texto completo
2019
Vuguls, J., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Snepsts, G., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Libiete, Z., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Zalitis, P., Latvian State Forest Research Inst. Silava, Salaspils (Latvia)
Forestry in Latvia in the 20th century was strongly focused on the establishment and management of pure Scots pine and Norway spruce stands trying to avoid any admixture of other tree species. Knowledge on the economic feasibility of the mixed stands’ management is still rather poor in Latvia, while at the same time the establishment of mixed stands of Norway spruce and birch species has become an attractive management objective in Finland and Sweden. This paper used the data from the Latvian National Forest inventory to quantify the amount of birch stands with the second layer of spruce, as the first step to justify the development of recommendations for alternative management options in this type of stands. According to the results, there are 121 752 ha of birch stands with the second layer of Norway spruce, and most of those are located in Hylocomiosa, Oxalidosa, Myrtillosa mel. and Myrtillosa turf.mel. site types. The mean standing volume of birch stands with Norway spruce understorey was higher than in birch stands with no spruce understorey, and Hylocomiosa, Oxalidosa, Myrtillosa mel. were the most productive site types both in terms of total standing volume and that of the Norway spruce growing in the second layer. Analysed data also revealed that the management of birch stands already now differs strongly in state and private forests, in the latter being more focused on selective fellings. It is possible to develop and test alternative management methods of birch stands with the second layer of Norway spruce to maximise yield and reduce expenses of forest regeneration.
Mostrar más [+] Menos [-]Post-storm regeneration of Norway spruce Texto completo
2019
Snepsts, G., Latvian State Forest Research Inst. Silava, Salaspils (Latvia); Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Donis, J., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Strelnieks, K., MVR LUX, SIA, Riga (Latvia) | Krisans, O., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Desaine, I., Skogssallskapet, SIA, Riga (Latvia) | Adamovics, A., Latvian State Forest Research Inst. Silava, Salaspils (Latvia)
Impact of abiotic (wind, summer drought) and secondary (bark beetle (Scolytinae)) or primary (cervids (Cervidae)) biotic factors affect the survival of Norway spruce (Picea abies (L.) Karst.) that is an economically important tree species. Norway spruce is mostly regenerated via planting – thus with significant investment. Therefore it is important to improve the resistance of Norway spruce stands as much as possible. Aim of the study was to characterize damages in Norway spruce stands by cyclonic wind storm and the regeneration of the stands, destroyed by the storm. Data from 4491 Norway spruce dominated stand, destroyed by the storm of 2005, from State Forest service database were obtained. Areas of post-storm sanitary clearcuts ranged from 0.1 to 7.6, mean 0.9 ± 0.02 ha. Most of the clearcuts were larger than 0.5 ha, demonstrating a relatively large size of gaps created by this natural disturbance. Changes of dominant trees species after the storm were statistically significantly affected by the forest type and type of regeneration. Overall, it happened in 55% of the former Norway spruce areas and was predominantly in cases, where natural regeneration was practiced. No indications of measures to increase stability of future stands against wind damages were found.
Mostrar más [+] Menos [-]Analysis of landscape paintings to highlight the importance of forest ecosystem services in Latvia Texto completo
2019
Paulina, I., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Libiete, Z., Latvian State Forest Research Inst. Silava, Salaspils (Latvia)
Forests and woodlands provide a wide variety of ecosystem services that are usually classified within three categories: provisioning services, regulating (supporting) services and cultural services. While provisioning and regulating services are widely analysed, there is a lack of information about the cultural ecosystem services, particularly some sub-categories of these. In this study, we have focused on inspiration for creativity as a sub-category of cultural ecosystem services provided by forests and analysed the depiction of forest ecosystems in landscape paintings of Latvian artists. It may be concluded that forest ecosystems serve as an important source of inspiration for creativity and art, as may be seen in the landscape paintings of Latvian artists of the 20th century. Characteristic landscape features of birth and living places of the artists are reflected in their works. The performed analysis is the first of its kind in Latvia, and it may be further expanded, either by incorporating other aspects of creativity or adding economic dimension, for example, by surveying the art market.
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