839 research outputs found
Drought resistance of willow short rotation coppice genotypes
No full textThis thesis reports on an investigation of drought resistance of willow SRC genotypes. Experiments were conducted at Silsoe, Bedfordshire, in pots and field trials in 2002 and in lysimeters in 2003 to evaluate the range of water use efficiency (WUE) of 50 willows varieties (Salix sp.) and isolate morpho-physiological traits related to WUE and drought resistance. Within the genotype pool tested there was a wide range of responses. The results depict the morpho-physiology of an ideal candidate that plant breeding could produce for drier area of UK, which are summarised below. Its cuttings do not develop calluses when stored in darkness at +4°C. After planting, the candidate does not grow rapidly but has an early exponential phase of stem elongation, after a year of growth it has few stems per stool ( 8) hairless leaves are characterised by small adaxial epidermal cells (AECS < 330µm2). The ideal candidate prioritises less biomass to its root system (root/shoot < 0.8) mainly in the top 0.2 m. When grown under optimum condition, the large leaf area has high stomatal conductance and leaf temperature. As water stress progresses, the leaf area decreases leaving little time for leaves to senesce and few yellow leaves remain on the stems. The stomatal conductance decreases slowly and the leaf temperature is almost unaffected. If water stress occurs before August the candidate is able to recover faster the initial physiological state and grow new leaves when re-watered. The results indicate that the best parents to produce such candidate are S. viminalis and S. schwerinii or their related hybrids. Water use (WU) of high yielding willow short rotation coppice hybrids is similar which indicates that the opportunity to reduce WU is limited and that productivity can be only improved by increasing WUE to produce above ground biomass and drought resistance. The current willow breeding programme has great chance to produce hybrids with high WUE however the production of a progeny population from high yielding hybrids that contrast widely in resistance to water stress is recommended. In theory, from such a population, valuable data on morpho-physiological traits related to drought resistance and high WUE can be collected and help genomics to develop quantitative trait loci to the condition that reference hybrids are grown along to quantify the level of water stress experienced by the planting
Willow growth in response to nutrients and moisture on a clay landfill cap soil. II: Water use
No full textThis paper describes studies into the effects of soil factors and water stress on water use by willow (Salix viminalis L.) on a clay landfill cap soil and a sandy loam. Individual plants were grown in lysimeters containing these soils under different watering regimes and with different soil amendment treatments. Stemflow and throughfall were measured to determine rainfall entering the lysimeters and evapotranspiration (ET) calculated from a water balance. With plentiful water, seasonal ET increased annually in most treatments, reflecting increases in plant leaf area and dry matter production. For the most vigorous plants, in the sandy loam treatment, it increased from about 360 l plant-1 in the establishment year to almost 1200 l plant-1 in the third year. Seasonal ET was highly correlated with leaf area duration. Nutritional amendment of Oxford clay resulted in plants with larger leaf area and higher dry matter production and seasonal ET than in the unamended treatment. Water stress reduced seasonal ET by up to 41%, as a result of defoliation and stomatal closure. In unstressed plants, in the sandy loam treatment, daily ET rates per unit leaf area reached a maximum of about 1.5 l m-2 d-1 in July. Without nutritional amendment, water use efficiency (WUE) calculated from plant ET and root, stump and stem dry weight, was low for the unamended Oxford clay treatment (1.4 g kg-1) but was similar in the amended clay (5.0 g kg-1) and sandy loam (4.9 g kg-1) treatments. The study has shown the dependence of biomass production by willow on Oxford clay on both nutritional amendment and water availability. Although both nutrients and water could be supplied at these sites by growing SRC within a leachate management system, there are several practical issues like the narrow window of opportunity for mechanised operations and concerns about long-term sustainability which still need to be addressed
Valuing the risk associated with willow and miscanthus relative to conventional agricultural systems
No full textThe agronomic characteristics of willow and miscanthus make these crops highly susceptible to risk. This is particularly true in a country such as Ireland which has limited experience in the production of these crops. Issues such as soil and climate suitability have as yet to be resolved. The lengthy production lifespan of energy crops only serve to heighten the level of risk that affects key variables. The uncertainty surrounding the risk variables involved in producing willow and miscanthus, such as the annual yield level and the energy price, make it difficult to accurately calculate the returns of such a project. The returns from willow and miscanthus are compared with those of conventional agricultural enterprises using Stochastic Efficiency with Respect to a Function (SERF). A risk premium is calculated which farmers would need to be compensated with in order for them to be indifferent between their current enterprise and switching to biomass crop production. With the exception of spring barley, a risk premium is required if farmers are to be indifferent between their current enterprise and willow or miscanthus. The value of the risk premium required to entice farmers to switch to miscanthus production is significantly less than that required for willow. This suggests that a greater level of risk is associated with willow than with miscanthus.Biomass, SERF, Risk Premium, Resource /Energy Economics and Policy, Risk and Uncertainty,
Combustion characteristics of some imported feedstocks and short rotation coppice (SRC) willow for UK power stations
No full textThe availability and sustainability of biomass is very crucial in the production of energy using biomass. Currently nearly two thirds of the biomass in the UK is being imported due to the limited supply of indigenous resources. The Green House Gas (GHG) emissions from importing these fuels are very high. The imported feed
stocks studied here (PKE, shea, olive and DDGS) exhibited high N and ash contents and also high slagging and fouling tendencies which are undesirable fuel traits. The
high N contents and S content (in the case of DDGS) emit NOx and SOx emissions respectively which cause acid rain and photochemical smog and are harmful to human health. Due to the poor quality of these fuels for use in boilers and furnaces, and the need for Green House Gas savings, indigenous fuels with better combustion properties need to be produced.
Energy crops like SRC willow and Miscanthus have remarkably better fuel properties (eg low ash and nitrogen contents) and there is potential to grow them in the UK. In order to help farmers to increase the yields and grow these crops in a more sustainable way, some agronomic studies have been carried out. The influence of 6 different fertilizer treatments with varying nitrogen levels, (0, 150 and 250
Kg/hectare), the addiition of K (150Kg N + 100Kg K), the addition of S (150 Kg N + 80 Kg S) and sewage pellets on SRC willow are studied. These crops are sampled twice a year for 3 years. It was found that fertilizer treatments do have an impact on the fuel properties (eg the application of N and K increase the C content and the CV
of the fuel). Different parts of the crop also exhibit different fuel properties (eg leaves have higher nitrogen and ash contents which are undesirable qualities during
combustion) hence it is important to avoid such parts. Sampling time also has a very big impact as the composition of the crop changes over the growth period. The optimum harvest time for SRC willow would be spring, after senescence when the leaves have fallen and some of the nutrients have translocated into the soil for the
next growing season.
Different genotypes of SRC willow with varying biochemical compositions were also studied to enable farmers to try and breed different genotypes with desired fuel properties for the next generation. 6 genotypes with varying biochemical
composition (highest and lowest hemicelluloses, cellulose and lignin contents) were studied. From these, one genotype S.elaeagnos Scop showed remarkably different properties compared to the other 5 genotypes. All the genotypes except S.elaeagnos Scop had very high ash melting temperatures (>1500oC) and low slagging and fouling tendencies. S.elaeagnos Scop exhibits good grinding properties. The
pyrolysis products of SRC willow are highly sensitive to its hemicelluloses and lignin contents. Due to its different properties S.elaeagnos Scop is of great interest
for further investigation especially for its grinding ability.
Overall, there is a potential for the UK to grow its own SRC willow. A larger dataset is required for the fertilizer application experiment to make firm conclusions since it is insufficiently small at the moment. A larger selection of genotypes would also need to be studied in order to help farmers breed a larger variety of SRC willow
Allen Collection; no.10684
No full textBlack and white image of a large conglomerate cliff. Three caves are pictured above the base of the cliff. Foreground; along bank of dry creek bed are small Oak, Willow, Sycamore, and Cottonwood trees. Written in white pencil below image on matte paper; "'Up on the Sycamore' Find the Cliff Dwellers." Image mounted on black matte paper.Master file: image/tiff; 194,338 KB; Computer Hardware: Intel Pentium (R) 4 3.20 GHz/ 1.99 GB RAM manufactured by Dell; Operating system: Windows XP 2002; Creation software: Adobe Photoshop CS2 version 9.0.2; Scanner: flatbed reflective scanner Microtek 1000XL; Scanner software: Microtek SilverFast Ai 6.4.2r2b; Scanned by Jason Dunlap on 2010-01-05
Review of the effects of energy crops on hydrology.
No full text1) MAFF has recently launched a scheme to support the expansion of the area of
energy crops grown in England in order to meet the nation’s Kyoto targets for
the reduction in CO2 emissions. This has highlighted concerns about the possible
effects of willow short rotation coppice (SRC) and Miscanthus on the hydrology
of catchments in which they are grown. High levels of water use by these crops
could result in less surface runoff, decreased aquifer recharge and hence
reduced stream flow (Chapter
Comics and human rights: an interview with G. Willow Wilson
No full textMaria Werdine Norris is a final year PhD candidate at the London School of Economics and Political Science. Her research is on the British Counterterrorism strategy and legislation, with a focus on nationalism, security and human rights. You can find her on Twitter as @MariaWNorris G. Willow Wilson is the award-winning author of Ms. Marvel. She lived in Egypt during her early twenties; her first graphic novel, Cairo, was based there and was listed as a top graphic novel for teens by both the American Library Association and the School Library Journal. Her comic series Air was nominated for the Eisner Award, and her first novel, Alif the Unseen, won the 2013 World Fantasy Award
13 Willow Ptarmigan
No full textLagopus lagopus (Linnaeus) 1758 Other vernacular names: Alaska ptarmigan, Alexander ptarmigan, Allen ptarmigan, Arctic grouse, red grouse (Scotland form), Scottish grouse, white grouse, white-shafted ptarmigan, willow grouse, willow partridge. Range: Circumpolar. In North America from northern Alaska, Banks Island, Melville Island, Victoria Island, Boothia Peninsula, Southampton Island, Baffin Island, and central Greenland south to the Alaska Peninsula, southeastern Alaska, central British Columbia, Alberta, Saskatchewan, Manitoba, central Ontario, central Quebec, and Newfoundlan
Willow River, British Columbia:
No full textThe collection consists of 1 large broadsheet (52 x 36 cm.) printed both sides in red and black, giving a general map of central British Columbia, an official plan of the townsite of Willow River, just north of Fort George, and b/w photos of northern scenes; accompanied by a detailed sheet with prices of the lots for sale in Willow River, and a promotional letter with original stamped mailing envelope from the Transcontinental Townsite Company (Winnipeg)--8 paragraphs promoting the real estate value of the lots for sale. Includes letter written and sent to Wm. L. Clay of Rochester, New York, from the secretary and general manager of Transcontinental Townsite Company of Winnipeg, Manitoba, dated April 9th, 1913, announcing the sale of lots in the town of Willow River, British Columbia
Children behind bars : why the abuse of child imprisonment must end /
No full textBased on a wide range of research and first-person interviews, this book presents the shocking truth about child prisons and argues passionately for their closing. Carolyne Willow draws on human rights legislation and progress in the care and treatment of vulnerable children elsewhere to outline the harsh realities of penal child custody-hunger, dirty cells, the authorized infliction of severe pain, bullying and intimidation, and much more. Exploring these issues through the lens of protection rather than punishment, this compelling book reaches beyond any one country to address the plight of child prisoners around the globe.Specialized.Previously issued in print: 2015.Includes bibliographical references and index.Based on a wide range of research and first-person interviews, this book presents the shocking truth about child prisons and argues passionately for their closing. Carolyne Willow draws on human rights legislation and progress in the care and treatment of vulnerable children elsewhere to outline the harsh realities of penal child custody-hunger, dirty cells, the authorized infliction of severe pain, bullying and intimidation, and much more. Exploring these issues through the lens of protection rather than punishment, this compelling book reaches beyond any one country to address the plight of child prisoners around the globe.Specialized.Description based on online resource; title from PDF title page (viewed on April 27, 2023)
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