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Productivity benchmarks for community-based genetic improvement of Abergelle, Central Highland and Woyto-Guji indigenous goat breeds in Ethiopia Полный текст
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 Полный текст
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.
Показать больше [+] Меньше [-]Reproduction and survival analysis of Boer and their crosses with Central Highland goats in Ethiopia Полный текст
2019
Mustefa, A. | Banerjee, S. | Gizaw, Solomon | Taye, M. | Getachew, T. | Areaya, A. | Abebe, A. | Besufekad, S.
Growth performance of Boer goats and their F1 and F2 crosses and backcrosses with Central Highland goats in Ethiopia Полный текст
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.
Показать больше [+] Меньше [-]Reproductive performance indicators of dairy cattle in selected small-scale dairy farms in semi-arid Eastern Kenya Полный текст
2019
Mungube, E.O. | Njarui, D.M.G. | Maichomo, M.W. | Olum, M.O. | Ndirangu, P.N. | Kabirizi, J. | Ndikumana, J. | Mwangi, G.
Habitat management for capercaillie Tetrao urogallus L. leks: the survey of vegetation changes Полный текст
2019
Straupe, I., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Liepa, L., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Zalite, A.A., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
The capercaillie Tetrao urogallus L. is a typical bird species inhabiting structurally diverse coniferous forests. To increase the habitat quality of capercaillie leks, experimentally the habitat restoration in degraded ecosystems has been practiced. The main habitat restoration events are related to the reversion of hydrological regime and understorey layer management. The aim of this study was to find out how the management of lek sites – mowing of Ledum palustre L. and ground vegetation – promotes the regeneration of the vegetation typical of the capercaillie leks. Three sample plot blocks of 10x30 m have been established, which have been divided into 3 variants of 10x10 m. The first is a control plot, in the second plot an entire ground vegetation mowing was performed, while in the third plot – the ground vegetation mowing in a 3 m wide strip was carried out. The vegetation was determined using the BraunBlanquet recording form before the management – in August 2015, and after the management – in August 2017. The condition of the habitat of capercaillie is inadequate before management, since Ledum palustre prevails in the ground vegetation. Both types of ground vegetation management have had a significant impact on the projective cover of Ledum palustre. After mowing the entire area, it has decreased by half, but after mowing in a strip, it has decreased by 30%. The ground vegetation mowing in a strip enhances positively the regeneration of dwarf shrubs and herbaceous vegetation.
Показать больше [+] Меньше [-]Transformation of the organic matter of forest and postagrogenic soils of the boreal zone of Russia Полный текст
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.
Показать больше [+] Меньше [-]Impact of forest soil enrichment with nitrogen fertilizer on throughfall and soil water chemical properties Полный текст
2019
Karklina, I., Latvian State Forest Research Inst. Silava, Salaspils (Latvia);University of Latvia, Riga (Latvia) | Stola, J., Latvian State Forest Research Inst. Silava, Salaspils (Latvia)
A demand for wood resources is increasing. In addition to drainage and appropriate regeneration and thinning, the forest soil fertilization may increase the future harvest rates. Therefore, the improved growth of forest stands raises in priority among the research topics related to forestry. The objective of the study is to evaluate the impact of nitrogen fertilizer on soil water and throughfall water chemical composition to elaborate recommendations for the forest fertilization. The trials were conducted in a birch stand and in three coniferous stands. Nitrogen containing mineral fertilizer (ammonium nitrate) was distributed in the study sites, while the control plots were left without any treatment. The water samples were collected a season before and a season after the soil treatment. The pH level, total nitrogen, potassium and phosphate were determined in throughfall and soil water samples. The chemical properties of throughfall water differed depending on the forest stand type. The concentration of nitrogen was higher in throughfall water samples collected from the birch stand. The mean concentration of total nitrogen was 1.6 ± 0.3 mg LE−1 in the throughfall water samples from the birch stand compared to 1.03 ± 0.11 mg LE−1 in the throughfall water samples from the coniferous stands. Although the forest soil was enriched with the nitrogen fertilizer, there was a significant increase in concentrations of potassium and phosphate in soil water samples from certain stands. It can be explained with changes in pH level that occurred after the forest soil treatment with ammonium nitrate. There was also a significant increase in total nitrogen concentrations in soil water samples at the depth of 30 cm from the treated plots of the coniferous stands – 15 ± 6 mg LE−1, compared to 1.5 ± 0.03 mg LE−1 in the samples from the control plots. However, the concentrations decreased within two months and remained at a steady rate – slightly above the control level.
Показать больше [+] Меньше [-]Developing a framework for characterizing recreational potential of forest areas using weighted criteria analysis Полный текст
2019
Jurmalis, E., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Libiete, Z., Latvian State Forest Research Inst. Silava, Salaspils (Latvia)
Forests offer a wide variety of ecosystem services, including cultural or recreational services. In that sense, state-owned forest lands hold the biggest responsibility to acknowledge and provide these services, where it is economically and ecologically viable. Suitability analysis has been extensively used to provide information on species conservation measures, and it is possible to apply similar techniques for potential supply of recreational services. A simple weighted overlay analysis was conducted to locate forest land areas most suitable for potential recreational activities. Several criteria were selected for the analysis, including forest stand parameters such as forest stand age, forest stand type and species, topographical diversity and remoteness. Basis for the weighting of the selected criteria were obtained from the social surveys, previous research work done in Latvia and the Baltics, and European scale scientific data on recreation preferences. The analysis showed that 20% of the total model area analysed provide substantially high recreation potential. Furthermore, these preliminary data can be used for surveying and facilitating community involvement processes. Local tourism and nature leisure activities can be promoted by exploring possibilities of alternative forestry planning options, utilizing such multifunctional assessments of recreational supply.
Показать больше [+] Меньше [-]The efficiency of forest drainage system sedimentation ponds in the context of water quality Полный текст
2019
Kalvite, Z., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Libiete, Z., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Klavins, I., Latvian State Forest Research Inst. Silava, Salaspils (Latvia)
The establishment, maintenance and renovation of forest drainage systems are carried out to ensure the development of high quality forest stands and to secure access to forest resources, but it also poses a risk of erosion and increased discharge of suspended solids and nutrients associated with it. The aim of the study was to analyse the efficiency of standard-sized sedimentation ponds built by JSC ‘Latvia’s State Forests’ for sediment and nutrient retention during and after drainage network maintenance. To assess the efficiency of standard-sized sedimentation ponds six study sites were established and various chemical and physical parameters were measured for three years to evaluate water quality and to estimate runoff of plant nutrients and suspended solids. Sampling was carried out before and during drainage network maintenance and during two years following it. Despite the fact that some effect in reducing suspended solid export from catchments was observed, the results revealed insufficient efficiency of the sedimentation ponds in retaining plant nutrients and eroded matter during and after the drainage network maintenance. Retention of Ntot, N-NO3 sup(-) , P-PO4 sup(3-), N-NH4 sup(+) and DOC was ambiguous. It was concluded that other water protection structures should be considered or different parameters of sedimentation ponds should be used to improve the water quality exiting the drainage systems and entering waterbodies.
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