Browsing by Subject "irrigation"

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  • Christersson, Jenni (Helsingin yliopisto, 2015)
    This case study sheds new light on rural water use and related social, aconomic and environmental dimensions and proposes government intervention in order to ensure water rights and protect public value of fairness. The aim is to highlight farmers’ perspectives on irrigation water use and related obstacles, and specifically distinguish if views are connected to farmers’ underlying socioeconomic or agro-ecologic factors. For further considerations adaptive capacity of community for irrigation water fees is explored. The research material consists of semi-structured interviews for farmers (n=63), government organizations (n=3) and agricultural enterprises (n=2). Economic groups were formed via analysis of asset-based economic status. Grouping based on agricultural water use was conducted through categorization. Costs and lack of knowledge were identified as the main barriers for adopting advanced irrigation technology. The study showed prevailing allocation system is in need of reformation. When designing rural policy, farmers’ perceptions should be respected. Water allocation is considered unfair community-wide and social conflicts are largely faced. Those who do not suffer from conflicts are most commonly rich. Technology transfer offer potential benefits, but community needs to be mobilized. Grouping based on irrigation water usage may be used for targeting policies. Economic grouping may be used for distinguishing farmers’ behavior when designing change in economic conditions or conflict resolution strategy. The complementary role of this study is to bring out special focus on development for institutional capacity-building; strengthening the forcing nature of laws and user rights. This may reduce the attractiveness for corruption in the process. Under these conditions, the greatest benefits may be obtained by giving top priority instead of irrigation improvement, but conflict mediation and establishment of water markets.
  • Vitt, Anton; Babenka, Andrei; Bostrom, Elisabeth A.; Gustafsson, Anders; Lira, Ronaldo; Slizen, Veronica; Sorsa, Timo; Tervahartiala, Taina; Buhlin, Kåre (2020)
    To evaluate the effect of adjunctive antiseptic irrigation of periodontal pockets on microbial and cytokine profiles. Fifty-nine patients with severe periodontitis were allocated to one of three groups for scaling and root planing facilitated with different adjunctive antiseptics: 1% polyhexamethyleneguanidine phosphate (PHMG-P) (n = 19), 0.2% chlorhexidine (CHX) (n = 21) or distilled water (n = 19). Gingival crevicular fluid and subgingival bacterial samples were collected at baseline, and at 2 weeks, and 1 and 4 months. The levels of interleukin (IL)-1 beta, IL-8, IL-10, and IL-17A, matrix metalloproteinase (MMP)-8, Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola, Fusobacterium nucleatum,Aggregatibacter actinomycetemcomitans, and Prevotella intermedia were determined. There were no intergroup differences in cytokine concentrations and bacterial counts at any follow-up, however, varying patterns were observed. In the PHMG-P and water groups IL-1 beta expression peaked at 2 weeks and then gradually declined. In all three groups, the dynamics of MMP-8 concentration were non-linear, increasing by 2 weeks and then declining to below baseline (p > 0.05). P. gingivalis and T. forsythia declined within the first month and increased thereafter, not regaining the baseline level. Adjunctive antiseptic treatment was associated with changes in biomarkers and bacterial counts in the course of the study. The effects of adjunctive antiseptic irrigation were limited in the applied protocol.
  • Karhula, Tuomo (Helsingfors universitet, 2012)
    The aim of this research was to find out how split-root fertigation affects the tield and quality of greenhouse tomato grown under modern greenhouse conditions. The aim was to find out if split-root fertigation produces bigger and better quality crop than traditional fertigation. In addition water use efficiency was compared between the split-root and traditional fertigation approaches. The study was conducted at MTT Agrifood Research Finland (Piikkiö) during 3.4.- 24.11.2009 in greenhouse. In split-root fertigation approach the roots of the tomato plants were divided into two comparments where the other compartment was fertigated with low electrical conductivity (EC) solution and the other on with concentrated EC solution. In traditional fertigation treatment the roots were also divided into two compartments but both parts were fertigated with solutions of equal EC. In split-root fertigation plant is able to take water from dilute solution and nutrients from concentrated solution. High EC can inrcease tomatos quality but decrease yield. Split-root fertigation enables use of high EC and low EC solutions to achieve the best quality tomatoes and most yield. During the cultivation period, the EC values of the nutrient solutions were maintained in their target values for almost all the time. The traditional fertigation approach produced more marketable yield and first class yield in number of fruits per plant than the split-root approach. The differences in the two approaches were statistically significant. One of the most factors that decreased the volume of marketable yield by was blossom-end rot. Water use efficiency was calculated by dividing the marketable yield by the volume of the water used during growth season. The split-root fertigation approach produced 164 g/l and the traditional fertigation 171 g/l of fruits per used litre of water. However, the difference was not statistically significant. Further research on split-root fertigation is needed. Based on the literature it the concentrated compartment in the split-root fertigation system may induce drought stress signals, which eventually reduc optimal production.
  • Kymäläinen, Anni (Helsingfors universitet, 2013)
    In Finland, potato is cultivated on more than 22 000 hectares, which makes it one of the most important crops. Potato is considered drought sensitivive because of it´s shallow roots. Thus, irrigation is recommended to improve not only the yield but to ensure good tuber quality. However irrigation is increases production costs. Nitrogen fertilization also affects yield and tuber quality but excess nitrogen can increase costs, nutrient leaching and reduce tuber quality. Thus, the equipment that can be used to estimate nutrient deficiencies have become more common. The effect of irrigation and nitrogen fertilization on growth and tuber yield of potato was investigated during 2001 – 2003 at Potato Research Institute in Lammi, Finland. Irrigation methods were surface irrigation and subsurface drip irrigation. Nitrogen was applied as a single dose when planting or as sidedress. Further interest was to find out whether SPAD values could be used to evaluate both the demand and timing of potato nitrogen fertilization. Irrigation did not affect potato development, tuber yield or starch content. Irrigation methods had no effect on tuber yield either. However, irrigation reduced the yield of marketable tuber yield. The benefit of drip irrigation was the possibility of combined irrigation and fertilizer application. Nitrogen increased tuber yield. The potato stand that received nitrogen as a single dose produced the greatest yield. However, even the potato stand which did not receive nitrogen produced quite large yield, over 30 tn/ha. In 2003, the stands which were given sidedress nitrogen with drip irrigation produced even greater yield than the ones that had been given nitrogen as a single dose. The stands which did not receive nitrogen had highest starch content. The SPAD values were used when estimating the demand of nitrogen fertilization with drip irrigation. SPAD measurements are easily conducted and non-destructive. SPAD values can be used to estimate the demand and timing of fertilization, even though there seems to be slight delay until the values indicate the nutrient deficiency.
  • Peltonen-Sainio, Pirjo; Laurila, Heikki; Jauhiainen, Lauri; Alakukku, Laura (2015)
  • Väisänen, Janne (Helsingin yliopisto, 2019)
    Reducing global carbon dioxide emissions is one of the main targets in the fight against climate change. Forests are important carbon pools and the arid regions of the world hold a great carbon sequestration potential. Dryland afforestation could play a considerable part in climate change mitigation. The aim of this study is to understand plantation forestry and the costs of afforestation work in arid and semi-arid regions. The main objective of the study is to estimate the establishment costs of 5.000-hectare irrigated forest plantation in Morocco, planned by the Finnish energy company St1. The plantation establishment costs are consisted of labor factors, such as preparing and mapping the cultivated area, fencing, seedling production, tillage, planting and aftercare, and other maintenance operation. The irrigation cost consist of developing the irrigation system, operation and maintenance costs and the price of desalinated seawater used in the plantation. The research timeframe was set to be from 0 to 5 years, assuming that this period covers the major cost factors of the plantation establishment. According to the results, the total establishment cost of the St1’s 5.000-hectare forest plantation, planned in Morocco, is estimated to be approximately EUR39 million and the cost per hectare around EUR7800. The total cost of cultivation is estimated to be about EUR18 million and the total cost of irrigation in the first four years are around EUR21 million.