• Field Case Studies of Soil Organic Matter Sequestration in Lithuania and the UK.

      Booth, Colin A.; Fullen, Michael A.; Jankauskas, Benediktas; Jankauskienė, Genovaitė; Slepetiene, Alvyra (WIT Press, 2008)
      Investigations have assessed the environmental benefits of soil organic matter (SOM) storage at two long-term European experimental research sites: (i) SOM data from a soil conservation (set-aside) site in the UK and (ii) SOM data from a carbon sequestration benchmarking site in Lithuania. The first case study (Hilton, UK) illustrates the environmental benefits of changes in SOM content before and after the adoption of set-aside, a recognized soil conservation technique. Ten run-off plots (7–15° gradients) were put to ley in 1991. Run-off and erosion rates decreased to tolerable levels once ~30% vegetation cover had established and remained low (mean of 69 plot years 0.21 t ha–1 year–1, SD 0.14). Meanwhile, SOM content increased consistently and significantly on the set-aside plots (mean of 2.22% by weight in 14 years) and soil erodibility significantly decreased. Results suggest using grass-leys for set-aside is a viable soil conservation technique, which may also contribute to carbon sequestration. The second case study (Kaltinenai, Lithuania) addresses the issue of comparing international SOM databases to assist carbon modelling and carbon sequestration estimates. Five analytical approaches have been used to calculate SOM. Linear correlation and paired regression equations were used to calculate the various techniques. Correlation coefficients varied between r = 0.83–0.98 (n = 92, 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. However, it also demonstrates the potential difficulty of international carbon benchmarking, as part of the global policy to ameliorate climate change.
    • Field studies of the effects of jute geotextiles on runoff and erosion in Shropshire, UK

      Mitchell, David J.; Barton, A.P.; Fullen, Michael A.; Hocking, Trevor J.; Zhi, Wu Bo; Zheng, Yi (Wiley InterScience, 2003)
      Jute geotextiles are widely used to stabilize steep banks and road cuttings. Jute protects bare surfaces until seeded grass becomes established, then after several years, the jute decays. To evaluate two types of jute geotextiles, eight erosion plots were established in July 1994 at the Hilton Experimental Site, Shropshire, UK. On 10 April 1995, the plots were treated as follows: (1) jute geotextile net; (2) jute mat; (3) perennial rye grass (Lolium perenne); and (4) bare soil, with duplicates of each treatment. Over one year, sediment yields from jute net and jute mat were 1.1% and 1.2%, respectively, of the yield from the bare control. Although both had similar soil protection qualities, runoff was very different. The runoff from the jute net was 35% and the jute mat 247% of the control. Results demonstrate the effectiveness of jute net for erosion and runoff control, while the jute mat may both conserve soil and 'harvest' rain or redirect runoff.
    • Grass ley set-aside and soil organic matter dynamics on sandy soils in Shropshire, UK

      Fullen, Michael A.; Booth, Colin A. (Wiley, 2006)
      Erosion plot studies at the Hilton Experimental Site, Shropshire, UK, evaluated the effects of set-aside on runoff, erosion and soil organic matter (SOM) dynamics. Ten runoff plots (slope angles 7-15°) were put to a grass ley in April 1991. Runoff and erosion rates during nine years were low, despite the occurrence of potentially erosive rains. Mean runoff was 0·24 per cent of precipitation (SD = 0·20, n = 89 plot years), compared with a 15-year mean value of 0·13 per cent (SD = 0·04) on permanent (control) grassland. The mean plot erosion rate was 0·21 t ha-1 a-1 (SD = 0·14, n = 69 plot years). Mean SOM content increased consistently and sign fi a tly on the set-aside plots, by a mean value of 1·07 per cent by weight (i.e. 1·07 g per 100 g of soil) in ten ye rs, from 2·04 per cent (1991) to 3·11 per cent (2001). Soil erodibility after six years of set-aside (sampling date 24 April 1997) was determined using a drip-screen rainfall simulator. Soil aggregate stability was higher on the grassed soils, compared with set-aside and bare arable soils. Despite no significant (P > 0·05) differences be w en grassland and set-asid oils, both these treatments were s gnificantly (P < 0·001) diff rent from bare soils. Contrary to the usually strong relationship between SOM and clay content, the percentage silt (r = 0·52, P < 0·001, n = 50) exhibited a stronger correlation with SOM than percentage clay content (r = 0·37, P < 0·01, n = 50). Furthermore, there were equally strong correlations between SOM and cumulative particle size fractions of both clay and silt contents (r = 0·51, P < 0·001, n = 50). In the absence of significant quantities of clay in these sandy soils, silts assist binding of SOM, which has significance for assessing soil carbon sequestration potential. Finally, future SOM and soil organic carbon benchmark work at the Hilton Site will improve harmonization of global SOM databases and enhance international estimates of rates and potential for soil carbon sequestration.
    • ShropshireA pilot project on the potential contribution of palm-mat geotextiles to soil conservation

      Davies, Kathleen; Booth, Colin A.; Fullen, Michael A. (Wiley InterScienceWiley, 2006)
      Geotextiles constructed from Borassus aethiopum (black rhun palm) leaves are currently being investigated for their effectiveness in decreasing water erosion. The study aims to develop sustainable methods of soil conservation where the material meets selected criteria (readily available, simple and cost-effective to manufacture, provides immediate erosion control and possibly increases soil fertility and organic matter content). Grid mats were manufactured in a cottage workshop in The Gambia, West Africa. They are currently under investigation at the Hilton Experimental Site in Shropshire, UK. Eight runoff plots (10 × 1 m on a 15° slope) are being used, with duplicate treatments: (i) bare soil; (ii) grassed; (iii) bare soil with 1 m palm-mat buffer zones at the lower end of the plots; and (iv) completely covered with palm-mats. Results from one year of field study (2002-03) indicate sediment yield is 36·8 per cent from replicated covered plots and 35·9 per cent from the replicated buffer zone plots, compared to the control bare plots. Sediment yield equated to 0·45 t ha-1 from bare soil, 0·09 t ha-1 from grassed plots and 0·17 t ha-1 from both the covered and buffer zone plots. The results suggest palm-mat application as protective buffer strips is highly effective in temperate climates. Future work is intended to follow this pilot study and develop well-researched guidelines for practical field applications in other global regions, namely Africa, Southeast Asia and South America.
    • Spatial variability in precipitation within the Hilton Experimental Site, Shropshire, UK (1982-2006).

      Subedi, Madhu; Fullen, Michael A. (Wiley InterScience, 2009)
      Accurate precipitation measurements are essential for many hydrological and hydrogeological management strategies. Precipitation at the Hilton Experimental Site has been regularly measured since 1982. This paper summarises 157 rain gauge years of precipitation data, recorded between 1982 and 2006, using 11 rain gauges on the 0·5 hectare site. Precipitation varied markedly within the site. Precipitation totals were notably different between two adjacent rain gauges, the mean difference being 0·3% of the total. Variations in mean annual precipitation within the site were 8%. Spatial variations in wind turbulence appeared to be the main factor influencing intra-site variability. Precipitation totals varied with gauge exposure, with surface level gauges receiving 5·9% more precipitation than standard rain gauges, the difference being less lower down the slope. On a steep (15° ) slope, basal sections had 2·5-7·9% more precipitation. Upper gauges received less, probably due to turbulence as increased exposure on the top of the slope resulted in precipitation being carried over the gauge orifice. Results confirm that due attention must be given to the inherent variability of precipitation amounts when calculating precipitation inputs. Copyright © 2008 John Wiley & Sons, Ltd.
    • Summary of teaching and research activities on the Hilton experimental site, East Shropshire, 1976-2010

      Fullen, Michael A. (School of Applied Sciences, University of Wolverhampton, 2010)
      The Hilton Experimental Site is used for a range of studies on soil erosion and conservation and for studies on water, sediment and solute dynamics within the 40 km2 Claverley Brook Catchment. The site is located 15 km west of Wolverhampton and 8 km east of Bridgnorth at 52o33’05.7”N, 2o19’18.3”W (U.K. National Grid Reference SO778952). It covers 0.52 hectares (5,214 m2) and has an upper elevation of 67.46 metres O.D.. The soil is a loamy sand (Psammept) of the Bridgnorth series. The site was established in 1976 and possesses a meteorological station, 21 runoff plots and soil moisture measuring equipment, including lysimeters. Stream monitoring equipment includes an Ott stage recorder at a rated section, an automatic water sampler and bedload traps. The Hilton Site supports undergraduate, postgraduate and staff research programmes.
    • Temporal changes in soil temperature at the Hilton Experimental Site, Shropshire, UK (1982-2006): Evidence of a warming trend?

      Subedi, Madhu; Fullen, Michael A. (Informaworld (Taylor & Francis), 2009)
      Soil temperature variations at different depths at a research site over a 25-year period (1982-2006) are discussed. Based on a database of 11,498 individual soil temperature measurements in loamy sand (Bridgnorth series) soils, soil temperature at the Hilton Experimental Site in Shropshire, UK, significantly increased between 1982 and 2006. The surface soil (0 cm) warmed twice as fast (∼0.1°C year-1) as soil at 100 cm depth (∼0.05°C year-1) and thus implies progressively steeper thermal gradients with soil depth through time. The trend of increase in soil temperatures at 0 cm was generally greater in winter. These observations contribute to the growing corpus of evidence of global warming.
    • Utilization of Palm-mat Geotextiles to Conserve Agricultural Soils.

      Bhattacharyya, Ranjan; Davies, Kathleen; Fullen, Michael A.; Booth, Colin A. (International Erosion Control Association (IECA), 2009)
      Previously, most studies on the effectiveness of geotextiles on soil erosion rates and processes were conducted in laboratory experiments for <1 h. Hence, at Hilton (52o33' N, 2o19' W), East Shropshire, UK, we investigated the effectiveness of employing palm-mat geotextiles (Borassus and Buriti mats) to reduce rainsplash erosion, runoff and soil loss under field conditions. This study is a component of the European Union-funded BORASSUS Project. The effects of Borassus mats on rainsplash erosion were studied for ~2 years (2002-2004), and re-established in January 2007 on a 0o slope. There were 12 experimental plots (six plots completely-covered with mats and six bare plots; each measuring 1.0 x 1.0 m). Runoff-plot studies were also conducted on the loamy sand soil at Hilton for 2 years (2002-2004) with duplicate treatments: (i) bare soil; (ii) grassed, (iii) bare soil with 1 m Borassus-mat buffer zones at the lower end of the plots and (iv) completely-covered with Borassus-mats. Each plot was 10 x 1 m on a 15o (26.6%) slope. To confirm the results, another set of experiments have been in progress at Hilton since January 2007, with one additional treatment (bare soil with 1 m Buriti-mat buffer zones) compared with the earlier experiment. Runoff and soil erosion were collected from each plot in a concrete gutter, leading to a 0.02 m3 (20 liters) capacity receptacle placed inside a 0.14 m3 (140 liters) capacity container. Results (06/10/02-02/09/04; total precipitation = 1038.3 mm) showed Borassus mats on bare soil reduced total rainsplash erosion by ~50% compared with bare plots (9.64 kg m-2; 1.97 lb ft-2). The use of Borassus mats on bare soil (during 01/22/07-01/21/08; total precipitation = 919.2 mm) also reduced soil splash erosion by ~90%. During 03/25/02-05/10/04 (total precipitation = 1319.8 mm) complete cover of Borassus mats on bare soil reduced total runoff by ~19% and soil erosion by ~64%. Furthermore, Borassus mats as 1 m buffer strips on bare soil reduced runoff by ~36% and soil erosion by ~57%. During 01/08/07-01/14/08 (total precipitation = 923.4 mm), plots with Borassus and Buriti mats as buffer strips on bare soil reduced sediment yield by ~93 and 98%, respectively, and runoff by ~83 and 63%, respectively. Buffer strips of Borassus mats were also as effective as complete cover of the same mats. Thus, utilization of palm-mat geotextiles as buffer strips on bare plots (area coverage ~10%) is highly effective for soil and water conservation.
    • Utilizing palm-leaf geotextile mats to conserve loamy sand soil in the United Kingdom.

      Bhattacharyya, Ranjan; Fullen, Michael A.; Davies, Kathleen; Booth, Colin A. (Amsterdam: Elsevier, 2009)
      Despite palm-leaf geotextile mats having the potential to advance soil conservation technologies, field studies using geotextiles as complete cover and buffer strips in reducing rates of soil erosion by water are limited. Hence, the utilization of these mats as a potential soil conservation technique is investigated at Hilton, east Shropshire, UK (52°33′5.7″N, 2°19′18.3″W). 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. Field experiments have been conducted at Hilton since January 2007, to study the effects of emplacing Borassus and Buriti mats on the erosion of a loamy sand soil. Two sets (12 plots each) of experiments were established to study the effects of Borassus and Buriti mats on splash height and splash erosion. In both sets, 6 randomly-selected plots were completely covered with mats, and the rest were bare. Ten runoff plots (10 × 1 m on a 15° slope) were also established, with duplicate treatments to study the effectiveness of these mats for soil and water conservation. The treatments were: (i) bare soil; (ii) permanent grassed; (iii) bare soil with 1 m Borassus mat buffer zones at the lower end of the plots; (iv) bare soil with 1 m Buriti mat buffer zones at the lower end of the plots and (v) completely covered with Borassus mats. Results (during 22/01/07–21/01/08; total precipitation = 919.0 mm; n = 22 sets of measurements) indicate that Borassus mat-cover on bare soil significantly (P < 0.05) reduced total soil splash erosion by 90% compared with bare plots (24.81 kg m−2). Plots with Borassus mats had 51% less mean splash height than bare plots (n = 21 sets of measurements). However, Buriti mat-cover on bare soils had no significant (P < 0.05) effect on soil splash height or splash erosion. Results of runoff plots (08/01/07–14/01/08; total precipitation = 923.4 mm; n = 29 sets of measurements) showed permanent grass plots had the smallest runoff coefficient and the largest sediment yield reduction effectiveness (SYRE). Total runoff from the Borassus buffer zone plots (4.1 L m−2) was 83% less than the bare plots and total sediment yield was 93% less than the bare plots (2.32 kg m−2). Although, Borassus buffer zone plots had similar effects in reducing soil loss to Borassus completely-covered plots, the later treatment yielded 50% more runoff. Borassus buffer strip plots had less SYRE than the Buriti buffer zone plots. Mass per unit area and thickness of both geotextiles decreased after 3 months of surface application. However, moisture sorption depth and cover percentage of both geotextiles increased. Hence, it is recommended to cover palm-mat geotextiles as buffer strips for soil and water conservation on erodible moderate slopes.