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Hypotheses on inland valley development for smallholder dairy production in three West African countries Côte d'Ivoire, Mali and Nigeria
2007
Agyemang, K. | Yapi-Gnoare, C.V. | Ouologuem, B. | Barje, P.P. | Adediran, S.A.
A set of pre-formulated hypotheses about the potentials of inland valleys to agricultural production in general, and livestock (dairy) - based enterprises in particular, were tested with data collected from five regions comprising 71 villages/towns and 630 households in three countries (Nigeria, Mali and Côte d'Ivoire). The study was undertaken to test hypothesis concerning the potentials of the inland valleys systems to agricultural production, and those pertaining to the intensification of livestock production in the valleys systems and their relationships with demand for livestock (dairy) products. Results from the analysis showed that many of the previously held views about inland valley and their potential were supported by the data from the three countries. Most of the hypotheses relating directly with inland valley potentials were accepted in the majority of locations. However, there were few hypotheses which were not supported by data from all countries and study sites. The overall assessment from the surveys is that the potentials of the inland valleys towards dairy production are currently good in all the countries and could be better if the resources available in the inland valley environments (for example crop residues) are better managed and utilized. Intensive use of inland valleys was related more to population density than access to market. Similarly consumption levels of domestic dairy products were influenced by population concentration. Instead access to market influenced positively farmers' practices towards specialization and intensification of dairy production. Increase demand for milk and dairy products is met by intensification and not by increase in herd size. Efforts to ensure continued milking through feeding was not related to herd size. As revenues (sales and home consumption) increased, more lands were left to fallow. These results confirm the assertion that the presence of inland valley systems for cropping and livestock rearing promotes diversification of agriculture, and presumably reduces farmers' production risks.
显示更多 [+] 显示较少 [-]Territorial organisation of game management in Latvia
2010
Baumanis, J., Latvia Univ. of Agriculture, Jelgava (Latvia) | Ozolins, J., Latvian State Forest Research Inst. Silava, Salaspils (Latvia)
The number of the most important game animals of artiodactyla species (moose, red deer, roe deer, wild boar) has been increasing in Latvia during the last 10 years. At the same time, the number of hunting districts where the census of these game animals is taken is also increasing, whereas the average area of the districts is diminishing. The studies show that at present the area of many hunting districts is notably smaller than the individual territory inhabited by these species. This particular study aims at establishing whether there is a relationship between the area of a hunting district on which a census is taken and the number of animals counted, as well as whether the number of animals is really increasing or the increase in the number is attributed to an increase in the census unit number. It was established that in respect of the four species there is a significant correlation between the area of the hunting district and the density of animals in the district. The number of moose and red deer may be assessed more objectively in the districts with an area exceeding 5,000 hectares. The census of roe deer and wild boars is notably influenced by the area of the territory where the census is taken, but the analysis does not explicitly show whether the number of roe deer and wild boars is under-assessed in large districts or over-assessed in the small ones.
显示更多 [+] 显示较少 [-]Litter invertebrate communities in pine forests of different age (Baranivka area, Ukraine)
2012
Kalynovskyi, N., Zhytomyr National Agroecological Univ. (Ukraine)
Litter invertebrate communities in pine forests of different age (cut, six-year-old, 45-, 62-, and 105-year-old) in the Baranivka area of Zhytomyr Polissya (northwestern part of Ukraine) were studied. Samples were collected in April, August, and November 2011. 99% of extracted invertebrates were represented by mites (Acari) and springtails (Collembola). With forest age, the following tendencies were observed: mean absolute density of mites, springtails, and all litter-inhabiting animals increased; relative abundance of mites increased, but relative abundance of springtails decreased; taxonomic richness of invertebrate communities increased. In all samples, the most represented taxon was suborder Oribatida. The most diverse litter invertebrate community was in the 45-year-old forest. Similar compositions of invertebrate community were in the 45-, 62-, and 105-year-old forests as well as the cut and six-year-old ones.
显示更多 [+] 显示较少 [-]Distribution and status of common juniper (Juniperus communis L.) in Lithuanian pine stands
2012
Vaitkeviciute, R., Aleksandras Stulginskis Univ., Akademija, Kauno reg. (Lithuania)
Distribution and status of common juniper (Juniperus communis L.) in Lithuanian Pine stands are investigated in the study. The research was conducted in pure pine stands on sites with normal humidity and poor fertility in South – South Eastern parts of Lithuania. 40 stands were selected for data collection. Temporary rectangular sample plots with area of 10 square m were selected. According to method of underbrush evaluation, diameter root neck level, height and state index was measured for 3 juniper individuals located near the centre of sample plots. The number of sample plots depended on the area of each stand, but it was not lower than 10 in each stand. Average diameter of junipers was 3.03 cm, average height – 2.03 m. It was determined that average density of juniper individuals is 5055 individuals per hectare, and separately in vacciniosum and vaccinio – myrtilosum forest types - 4844 and 5282 individuals per hectare respectively. Average state index of juniper individuals in 6 grade scale was 2.96, which is near to grade 3 (slightly damaged). Results of the study show that distribution, status and dendrometric characteristics of junipers are different in adjacent regions of pine provenance.
显示更多 [+] 显示较少 [-]Mean basic density and its axial variation in Scots pine, Norway spruce and birch stems
2017
Liepins, J., Latvian State Forest Research Inst. Silava, Salaspils (Latvia);Latvia Univ. of Agriculture, Jelgava (Latvia) | Liepins, K., Latvian State Forest Research Inst. Silava, Salaspils (Latvia)
The objective of this study is to evaluate the performance of models developed by Repola (2006) to estimate the vertical changes of the basic density of Scots pine (Pinus sylvestris L.), Norway spruce (Picea abies [L.] Karst), and birch spp. (mainly Betula pendula Roth) stemwood in the forests of Latvia and to develop a model for the estimation of average knot-free stem density with bark (SD) using diameter at breast height as an independent variable. The study material comprised a total of 81 spruce, 102 pine, and 105 birch stems representing a wide range of tree growing conditions in Latvia and covering all age classes. The knot-free stemwood density (SWD) of pine and birch demonstrate strong vertical dependence along the stem, while for spruce the variation pattern was less pronounced and seemed to be nearly constant along the stem. The SWD estimated by Repola’s models was 4.3% lower for spruce, but 3.4% higher for pine and 2.2% for birch comparing to average values obtained in this study. Sigmoidal regression equations constructed in our study explained 67%, 27% and 54% of variations for predicting SD for pine, spruce and birch, respectively. Birch stemwood has a highest basic SWD – 470 kg mE-3, followed by pine – 397 kg mE-3 and spruce – 385 kg mE-3. According to our results, the birch bark turned to be denser than the birch stemwood, being vice versa for the studied coniferous species.
显示更多 [+] 显示较少 [-]A survey of statistics of building fires in Latvia
2020
Grants, E., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
A survey of 8985 records on all fires in Latvia in 2019 gathered by State Fire and Rescue Service was performed to find out if gathered data is suitable and complete for establishment of statistical database for fire protection engineering. The purpose of the survey is to assess suitability of provided content for further studies of the characteristic building fire occurrence probabilities in different building occupancy classes and to obtain solid background for calculations of national values of fire activation partial safety factors which could be implemented in National Annex of Eurocode 1 part 1–2. Study contains data about the total number of building fires with relevance to their occupancy types and review of recorded fire causes for residential buildings that provide overall insight on typical causes of fires in dwellings.
显示更多 [+] 显示较少 [-]Relation between spread of cultural heritage and indicators of regional development: case of Latgale region (Latvia)
2007
Paiders, J., University of Latvia, Riga (Latvia) | Sture, I., University of Latvia, Riga (Latvia)
The paper deals with statistic analysis of the relation between variables of cultural heritage and that of regional development in Latgale region. Latgale was selected as the study area - it is one of the five cultural or historical ethnographic regions of Latvia with stable original features, which are formed in the result of the specific historical processes but stands out among other regions of Latvia with the lowest indicators of development. According to the results of analysis of correlation, the number of architectural and archaeological monuments per 1000 people or their density in area have no close correlation with the major part of the parameters under examination. The analysis of regression was carried out between 'the number of architectural monuments against the area', and 'the natural logarithm from the density of population in 2005'. The ratio is expressed by the function y = 0.0339x**2 - 0.1422x + 0.1671, where y is the number of architectural monuments per square kilometre, but x - natural logarithm from the density of population (the number of people per square kilometre). The coefficient of determination for this relation is almost the same as for a functional one - 0.9499. Both for the coefficients of the equation and free member of equation have very high validity (t - empirical respectively 21.7; -11.1; 7.9).
显示更多 [+] 显示较少 [-]An analysis of the carrying capacity of Lakshadweep coral reefs
1997
Rodrigues, C.L.
The Chinyanja triangle in the Zambezi River Basin, southern Africa: status of, and prospects for, agriculture, natural resources management and rural development
2014
Amede, Tilahun | Tamene, Lulseged D. | Harris, D. | Kizito, Fred | Xueliang Cai