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To authenticate to the full-text of this article, please visit this link: http://dx.doi.org/10.1111/j.1365-2745.2009.01533.x Byline: Ingo Feeser (*), Michael O'Connell Keywords: biogeography; coprophilous fungal spores; environmental change; karst; land use; late Holocene; non-pollen palynomorphs; pollen analysis; soil erosion; vegetation dynamics Abstract: Summary The study focuses on species-rich, upland, heathy vegetation with arctic-alpine floristic affinities and Sesleria grasslands in the karstic Burren region, western Ireland. The investigations aimed at reconstructing the long-term development of these high conservation-value communities and the role of farming in their formation and long-term survival. The methods used included pollen analysis and 14C-dating of short monoliths and investigation of grykes (fissures in karstic limestone) for evidence of soil erosion. Special attention was paid to fossil, coprophilous fungal spores as indicators of local grazing. The strong local character of the pollen records facilitated identification of inter-site differences as well as regional patterns. It is shown that open pine woodland characterized the Cappanawalla uplands between c. 1500 BC and 500 BC. It is proposed that such woodlands, with floristic affinities to Scandinavian open pine woodlands on calcareous soils, provided a suitable environment for the present-day, open heath vegetation with species such as Dryas octopetala, Arctostaphylos uva-ursi, Geranium sanguineum and Empetrum nigrum. Burning of vegetation as a management tool was important in the uplands over most of the last two millennia. Firing seems to have ceased with the onset of more intensive grazing regimes in the 18th century. Synthesis. Upland palaeoarchives, derived from shallow peaty deposits, show that the upland Burren supported mainly plagioclimax Corylus-dominated woody vegetation and grasslands from c. 1500 BC (beginning of present record), until possibly as late as the 17th century AD. In the uplands of the north-western Burren, open, species-rich pinewoods with hazel dominated. The northern-arctic elements in the present-day upland flora survived clearances, involving initially Pinus sylvestris (c. 500 BC) and subsequently Corylus avellana (c. AD 1600). Colluvial material retrieved from grykes supports the idea of considerable soil loss occurring as late as the first and early 2nd millennium AD. The investigations highlight the potential of upland palaeoarchives, consisting of short sequences, for elucidating vegetation and land-use dynamics in karstic environments such as the Burren. Article History: Received 3 February 2009; accepted 9 June 2009 Handling Editor: Richard Bradshaw Article note: (*) Correspondence author. E-mail: ingo.feeser@nuigalway.ie

To authenticate to the full-text of this article, please visit this link: http://dx.doi.org/10.1111/j.1745-5871.2008.00554.x Byline: LEA WITTENBERG (1), MOSHE INBAR (1) Keywords: forest fire; soil erosion; vegetation recovery rates; Mediterranean ecosystems Abstract: Abstract The Mediterranean ecosystem of Mt. Carmel, Israel, is subjected to an increasing number of forest fires of various extents and severities. The impacts of forest fires on runoff and erosion are widely documented and include increased peak flows and soil loss until the return of a vegetation cover. Most studies, however, treat fire as a single event, whereas the present study is aimed at exploring the long-term effects of repeated forest fires on eco-geomorphic processes. The study integrates the results of plot-based, detailed analysis of post-fire runoff and erosion with vegetation recovery analysis, at a temporal-spatial scale which includes the effect of reburning. Our results indicate that forest fires lead to a significant increase in runoff and sediment yields, particularly during the first two years following the disturbance, up to five orders of magnitude higher than from the adjacent unburnt control plots. Author Affiliation: (1)Department of Geography and Environmental Studies, University of Haifa, Haifa, Israel, 31905. Article History: Received 15 January 2007; Revised 29 October 2007; Accepted 27 August 2008 Article note: (*) Corresponding author. Email: leaw@geo.haifa.ac.il

To authenticate to the full-text of this article, please visit this link: http://dx.doi.org/10.1111/j.1745-5871.2008.00555.x Byline: BINGQI ZHU (1), XIAOPING YANG (1) Keywords: chemical weathering; detrital sediments; CIA; geomorphology; desert; China Abstract: Abstract Based on the analysis of major-element compositions of detrital sediments from the Taklamakan Desert of northwestern China, this paper aims to study chemical weathering in a hyper-arid desert environment. The major-element compositions are basically similar to the Upper Continental Crust but show a clear enrichment of CaO and depletion of [Na.sub.2]O and [K.sub.2]O, indicating the enrichment of carbonates and the decomposition of sodium and potassium silicates. The indexes of chemical alteration are relatively low and correlate negatively with the content of [Na.sub.2]O, implying that the degree of chemical weathering is weak and mainly controlled by the weathering of sodium feldspars. An A-CN-K model demonstrates that the detrital sediments from the Taklamakan Desert have a high homogeneity in the trend of chemical weathering. They are weathered less than sands and soil in many other Chinese deserts, and also less than similar detrital sediments in many other countries. This evidence suggests a low degree of mineralogical maturity in the Taklamakan Desert. The aeolian sediments of different ages have similar indexes of chemical weathering, suggesting that the degree of chemical weathering was consistent in the Taklamakan Desert throughout the period of aeolian deposition. The low degree of chemical weathering is caused principally by extreme aridity, rapid rejuvenation of detrital sediments associated with strong aeolian processes, and an intensive input of fluvial deposits, as well as a lack of vegetation. Due to the high concentration of erodible minerals, the desert is quite vulnerable to soil erosion and land degradation. Author Affiliation: (1)Institute of Geology and Geophysics, Chinese Academy of Sciences (CAS), P.O. Box 9825, Beijing 100029, China. Article History: Received 13 January 2008; Revised 2 August 2008; Accepted 8 September 2008 Article note: (*) Corresponding author. Email: xpyang@263.net.cn

To purchase or authenticate to the full-text of this article, please visit this link: http://dx.doi.org/10.1111/j.1745-5871.2008.00533.x Byline: J.P. TERRY (1), R. LAL (2), S. GARIMELLA (3) Keywords: floodplains; accretion rates; Cs-137 method; Labasa River; Fiji Abstract: Abstract The 137Cs (caesium-137) method was used to investigate medium-term rates of sediment deposition on the floodplain of the Labasa River, on Vanua Levu island in northern Fiji. The Labasa basin is commercially important for sugarcane farming, which provides much revenue and sustains the economy in the greater Labasa area. Alluvium was sampled at three riverbank sites in vertical increments of 30 mm. Measured net vertical accretion rates, based on analysis of depth-profiles of 137Cs activity, ranged from 10 mm yr.sup.-1 at a low-lying site near a tributary confluence with the main river, to 60 mm yr.sup.-1 on a levee that was elevated slightly above the adjacent floodplain. These rates of accretion are high, but in general agreement with rates recorded using similar methods in other tropical Pacific island river systems. Soil erosion under sugarcane on hilly parts of the lower Labasa basin is an important factor in rapid floodplain development. Observations made during Cyclone Ami, which traversed Vanua Levu island in early 2003, illustrate the major contribution of severe storm events to floodplain sediment supply, by triggering numerous landslides on catchment slopes and in-channel debris floods, and by generating large-magnitude overbank floods. Author Affiliation: (1)Department of Geography, National University of Singapore, 1 Arts Link, Singapore 117570. (2)Division of Physics, The University of the South Pacific, Private Mail Bag, Suva, Fiji Islands. (3)School of Engineering and Physics, The University of the South Pacific, Private Mail Bag, Suva, Fiji Islands. Article History: Received 14 September 2007; Revised 9 November 2007; Accepted 29 November 2007 Article note: (*) Corresponding author. Email: geojpt@nus.edu.sg

In the absence of direct erosion measurements, the soil activity of the fallout radionuclide caesium-137 ([sup.137]Cs) offers an attractive tool for the estimation of long-term (approximately 45 years) net surface and minor rill soil erosion rates for hillslopes. A transect-based soil sampling technique was applied to one woodland and five grazed pasture hillslopes in the Williams River water-supply catchment in the Hunter Valley, New South Wales. An Australian regression model (SOILOSS) relating net soil loss from runoff-erosion plots to [sup.137]Cs deficit in soils was used to calculate a weighted net surface and minor rill erosion rate for the six hillslopes. The net median surface erosion rates ranged between 0.00 and 0.64 t [ha.sup.-1] [yr.sup.-1] with the average median soil erosion rate of 0.19 t [ha.sup.-1] [yr.sup.-1] (std. dev. = 0.23), indicating that these hillslopes were unlikely to be major sources of sediment to the catchment's waterways. Net soil loss rates were also shown to be low in comparison to Australia-wide data and comparable to hillslope data obtained elsewhere in the same region. Minimum and maximum error bounds were provided with each erosion rate to account for radionuclide detector count error. For one hillslope the estimated error due to detection was 1.34 t [ha.sup.-1] [yr.sup.-1], while the remaining five hillslopes exhibited error of up to 0.41 t [ha.sup.-1] [yr.sup.-1]. Correlation analyses between the net soil loss rates and physical hillslope characteristics were non-significant. KEY WORDS Soil erosion; caesium-137; hillslopes; SOILOSS; sediment tracing; Reduced Major Axis (RMA) analysis

Historically land reserve programs have been used to reduce soil erosion. Slippage, which occurs when the number of acres enrolled in a reserve program is not met by an equivalent reduction of acreage in production, has limited reserve success, however. This study addresses the effect of slippage on conservation reserves in southwestern Kansas from 1988-1994. Slippage has varied considerably on both spatial and temporal bases. At one extreme the programs were 100% successful in removing land from production, but at the other extreme, slippage rendered reserve programs nearly useless. Overall, slippage in the study area has greatly reduced conservation reserve effectiveness. Key Words: agriculture, conservation reserves, slippage, Kansas, soil.