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Using palm-mat geotextiles for soil conservation: II. Effects on in situ soil particle size distribution and nutrient concentration

Tue, 01 Jan 2013 00:00:00 GMT

Title: Using palm-mat geotextiles for soil conservation: II. Effects on in situ soil particle size distribution and nutrient concentration Authors: Bhattacharyya, R.; Fullen, Michael A.; Booth, C.A.; Black, A.W.; Townrow, D. Abstract: Although geotextile mats have considerable potential for soil conservation, field studies on their impacts on soil particle size distribution and nutrient conservation are scant. Hence, field experiments were conducted at Hilton, east Shropshire, U.K. (52°33′5.7″N, 2°19′18.3″W) during 2007–2009, to study the impacts of palm-mat geotextiles on topsoil (0–5 cm) particle size distribution and changes in selected nutrients (total P, K, Ca, Mg, S, Zn, Cu, Fe, Mn, Mo and Cl). Geotextile-mats constructed from Borassus aethiopum (Borassus palm of West Africa) and Mauritia flexuosa (Buriti palm of South America) leaves are termed Borassus mats and Buriti mats, respectively. Ten runoff plots (10×1 m on a 15° slope) were established, with duplicate treatments. The treatments were: (i) bare soil; (ii) permanent grass; (iii) bare soil with 1 m Borassus-mat buffer zones (area coverage ~10%) at the lower end of the plots; (iv) bare soil with 1 m Buriti-mat buffer zones (area coverage ~10%) at the lower end of the plots; and (v) completely-covered with Borassus mats. Initial and final topsoil samples were collected and analysed for sand (fine, medium and coarse), silt (fine, medium and coarse), clay and selected nutrients. Results revealed that soil silt and clay contents significantly (Pb0.05) decreased in the Borassus completely-covered plots with a concomitant increase in proportion of sand content after ~2 years. Both Borassus and Buriti buffer strip plots also had lower soil clay contents, indicating that palm-mat geotextile cover significantly affected particle size distribution, even after only 2 years. Buriti mat-cover within the buffer strip plots resulted in notably higher decrease in mean (n=2) clay content, with a concomitant increase in mean (n=2) sand contents compared with mean (n=18) clay and sand contents of bare soils within the same plots. Data indicate that total P and total K contents with Borassus completely-covered plots significantly (Pb0.01) increased and total Ca content decreased after ~2 years. However, except grassed plots, all plots had significant (Pb0.05) increases in total P concentrations. Borassus buffer strip plots also had significant (Pb0.05) decreases in total Ca contents over the initial contents. The increases in total P and K contents within Borassus complete-cover plots were significantly (Pb0.05) higher than both grassed and Buriti buffer strip plots. Borassus buffer strip plots significantly (Pb0.05) decreased total Ca content compared to bare and grassed plots. Treatments had no significant (P>0.05) effects on changes in other selected nutrients (total Mg, S, Zn, Cu, Fe, Mn, Mo and Cl) concentrations. In summary, it is evident that despite significant (Pb0.05) decreases in soil clay and total Ca contents, use of Borassus mats as buffer strips was very successful in conserving or improving other selected soil properties.

Production of polyhydroxyalkanoates from waste frying oil by Cupriavidus necator

Sat, 01 Jan 2011 00:00:00 GMT

Title: Production of polyhydroxyalkanoates from waste frying oil by Cupriavidus necator Authors: Verlinden, Rob A. J.; Hill, David J.; Kenward, Melvin A.; Williams, Craig D; Piotrowska-Seget, Zofia; Radecka, Iza K. Abstract: Polyhydroxyalkanoates (PHAs) are biopolymers, which can replace petrochemical plastics in many applications. However, these bioplastics are currently far more expensive than petrochemical plastics. Many researchers are investigating the use of inexpensive substrates derived from waste streams. Waste frying oil is abundant and can be used in PHA production without filtration. Cupriavidus necator (formerly known as Ralstonia eutropha) is a versatile organism for the production of PHAs. Small-scale batch fermentation studies have been set up, using different concentrations of pure vegetable oil, heated vegetable oil and waste frying oil. These oils are all rapeseed oils. It has been shown that Cupriavidus necator produced the homopolymer polyhydroxybutyrate (PHB) from the rapeseed oils. The achieved PHB concentration from waste frying oil was 1.2 g/l, which is similar to a concentration that can be obtained from glucose. The PHB harvest from pure oil and heated oil was 0.62 g/l and 0.9 g/l respectively. A feed of waste frying oil could thus achieve more biopolymer than pure vegetable oil. While the use of a waste product is beneficial from a life-cycle perspective, PHB is not the only product that can be made from waste oil. The collection of waste frying oil is becoming more widespread, making waste oil a good alternative to purified oil or glucose for PHB production. Description: "Open access"

Factors influencing the effectiveness of an agro-environmental project in China

Sat, 01 Jan 2011 00:00:00 GMT

Title: Factors influencing the effectiveness of an agro-environmental project in China Authors: Subedi, Madhu; Hocking, Trevor J.; Fullen, Michael A.; McCrea, Alison R.; Milne, Eleanor Abstract: A case study identified the factors affecting farmers’ adoption of improved technologies extended by an agricultural development project in a rural village in Yunnan Province, China. Project effectiveness was influenced by: the success and appropriateness of recommended technologies and associated infrastructure development; the use of participatory approaches; material and advisory support to local stakeholders; clear explanations of project objectives to farmers; benefits for small landholders; land rights for farmers; farmers’ awareness and dissemination activities; and project duration. Farmers’ adoption of technologies should be a major criterion in evaluating project success.

A comparative study of analytical methodologies to determine the soil organic matter content of Lithuanian Eutric Albeluvisols

Sun, 01 Jan 2006 00:00:00 GMT

Title: A comparative study of analytical methodologies to determine the soil organic matter content of Lithuanian Eutric Albeluvisols Authors: Jankauskas, Benediktas; Slepetiene, Alvyra; Jankauskiene, Genovaite; Fullen, Michael A.; Booth, Colin A. Abstract: Large archive databases of soil organic matter (SOM) widely exist in Lithuania and the other countries of Central and Eastern Europe. Despite the demise of the former Soviet Union over 16 years ago, and Lithuania's integration as a full European Union state, difficulties of SOM data acceptance remain where these results are presented for publication in international journals, due to methodological differences between laboratory protocols. Therefore, the scientific pilot project ‘Carbon sequestration in Lithuanian soils’, supported by the Leverhulme Trust (U.K.), included an objective to correlate soil carbon methodologies, using Lithuanian Eutric Albeluvisols. A comparison of SOM content data acquired using five different analytical methods is reported. The research programme included a specific objective to correlate analytical methods for SOM analyses. A total of 92 Eutric Albeluvisol samples were collected from topsoil (0–0.2 m: Ap, n=36; Ah, n=10) and subsoil (0.2–0.4 m: Bt, n=46) horizons of 46 long-term experimental field plots at the Kaltinenai Research Station of the Lithuanian Institute of Agriculture. Each sample was then subsampled and analysed for SOM using dry combustion (by automatic elemental analyser), Walkley–Black (USDA), Tyurin photometrical, Tyurin titrimetrical and loss-on-ignition (LoI) methods (the later performed, in parallel, in both Lithuania and U.K. laboratories). Linear correlation and paired regression equations were calculated. Correlation coefficients between the sets of results varied between r=0.81–0.96 (from 0–0.2 m, n=46, P<0.001) and r=0.76–0.98 (from 0.2–0.4 m, n=46, P<0.001). Based on the strength and significance of these relationships, it is proposed that simple linear or more complex paired regression equations can be confidently employed to recalculate SOM data between various analytical methodologies. Future work will continue these investigations on other soil units and environments, hereby enhancing the database.