Objective: To study the growth, accumulation and soil nutrient content of each overseeded species under different interharvesting intensity treatments of Eucalyptus, and to explore the best re-cultivation method suitable for mixed overseeded species after Eucalyptus interharvesting. Methods: In Guangxi state-owned Qipo forest, Eucalyptus tailorii with different planting densities (DH32-29) were mixed with Castanopsis hystrix, Mytilaria laosensis and Michelia macclurei, and four different treatments (CK, LT, MT and HT) were established for re-cultivation of Eucalyptus near-mature forests with different logging intensities, and the differences in growth conditions and soil physicochemical properties of each species were analyzed. Results: (1) As the proportion of Eucalyptus allocation decreased, the growth of Eucalyptus diameter at breast height, tree height and individual wood volume could be promoted; the growth of the three parameters of HT and MT Eucalyptus were significantly different from LT and CK. (2) The average wood volume per plant of the set species in the CK and LT treatments was Mytilaria laosensis > Michelia macclurei > Castanopsis hystrix, while in the MT and HT treatments it was Mytilaria laosensis > Castanopsis hystrix > Michelia macclurei. (3) The differences in soil aeration, total saturated water holding capacity, capillary water holding capacity, and field water holding capacity in soil layers of different depth varied. In the same soil layer, soil aeration, total porosity and capillary porosity were HT > CK > LT > MT; saturated water holding capacity and capillary water holding capacity were HT > CK > LT > MT, while field water holding capacity was CK > HT > LT > MT. (4) Organic matter, pH, total nitrogen, total phosphorus, total potassium, fast-acting nitrogen, fast-acting phosphorus, and fast-acting potassium changed with varying soil depth in each treatment.
The propagation of plant material in the arracacha crop is commonly done vegetatively through asexual seed, this activity has allowed its multiplication and conservation over time. The plant material available is of low quality, affecting the development and potential yield of the crop and therefore the producer’s income. The objective of the research was to comparatively analyze two technologies for the production of arracacha seed: local technology and Agrosavia technology. The information for the local technology was obtained from surveys applied to farmers and the selection was made using the deterministic sampling technique, and for the Agrosavia technology through the recording of data and production costs in research lots at commercial scale. Descriptive statistics and calculation of economic return indicators were applied for the two situations. The results show that the use of quality seed allows obtaining higher seed production (251,559 unit ha-1) and tuberous roots (25,875 kg ha-1), being superior to local technology by 14% and 28% respectively; thus, the arracacha producer acquires greater economic efficiency by obtaining lower unit cost per kilo produced and better net income with a marginal rate of return of 316.45. The results achieved are useful for farmers, companies and entities that wish to produce quality seed and support the arracacha production system in Colombia.
The purpose of this article is to determine the equitability of airport and university allocations throughout Ethiopian regional states based on the number of airports and institutions per 1 million people. According to the sample, the majority of respondents believed that university allocation in Ethiopia is equitable. In contrast, the majority of respondents who were asked about airports stated that there is an uneven distribution of airports across Ethiopia’s regional states. Hence, both interviewees and focus group discussants stated that there is a lack of equitable distribution of universities and airports across Ethiopia’s regional states. This paper contributes a lesson on how to create a comprehensive set of determining factors for equitable infrastructure allocation. It also provides a methodological improvement for assessing infrastructure equity and other broader implications across Ethiopian regional states.
Species of the Moraceae family are of great economic, medicinal and ecological importance in Amazonia. However, there are few studies on their diversity and population dynamics in residual forests. The objective was to determine the composition, structure and ecological importance of Moraceae in a residual forest. The applied method was descriptive and consisted of establishing 16 plots of 20 m × 50 m (0.10 ha), in a residual forest of the Alexánder von Humboldt substation of the National Institute of Agrarian Innovation-INIA, Pucallpa, department of Ucayali, where individuals of arboreal or hemi-epiphytic habit, with DBH ≥ 2.50 cm, were evaluated. The floristic composition was represented by 33 species, distributed in 12 genera; five species not recorded for Ucayali were found. Structurally, the family was represented by 138 individuals/ha with a horizontal distribution similar to an irregular inverted “J”. However, there were different horizontal structures among species. It was determined that 85% of the species were in diameter class I (2.50 to 9.99 cm), being the most abundant Pseudolmedia laevis (Ruiz & Pav.) J.F. Macbr. (41.88 individuals/ha); and the most dominant were Brosimum utile (Kunth) Oken (1.71 m2∕ha) and Brosimum alicastrum subsp. bolivarense (Pittier) C.C.Berg (0.90 m2/ha). Likewise, P. laevis and B. utile were the most ecologically important. The information from the present research will allow the establishment of a baseline, which can be used to propose the management of Moraceae in residual forests in the same study area.
Lettuce (Lactuca sativa L.) is the main leafy vegetable grown in Brazil. Its productivity and quality are limited by the growing season, the nearby environment and the type of cultivar adopted. The objective of this work was to verify at different times of the year the best planting environment for lettuce cultivation in a semi-humid tropical climate. For this purpose, an experiment was set up in three different seasons (October–November 2014, January–March, May–July 2015). The experimental design was randomized blocks, in a 3 × 3 × 2 factorial arrangement, consisting of three seasons, three cultivars (cvs. Vera®, Tainá® and Rafaela®) and two growing environments (low tunnel with beds protected with mulching consisting of soil protection with plastic fabric covering, and beds without protection or conventional cultivation) and four replicates per treatment. Plant biomass, stem length, head diameter, number of leaves per head and crop productivity were evaluated as response parameters. The results showed that the May–July period favored biomass production, head diameter and productivity. Despite the similarity between varieties, the variety Vera® is more productive in biomass, number of leaves per head, stem length and productivity. The low tunnel planting system with mulching is adequate under the conditions evaluated for lettuce cultivation. This system in the May–July period favors a superior development in the characteristics biomass, head diameter and productivity, if compared to conventional cultivation during the October–November period.
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