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41.
Campbell TA Long DB Lavelle MJ Leland BR Blankenship TL Vercauteren KC 《Preventive veterinary medicine》2012,104(3-4):249-257
We studied the effects of baiting on feral swine (Sus scrofa) movements and corresponding likelihood of disease spread under real and simulated culling pressure. Our objectives were to determine the proportion of feral swine that used the bait station site, and if baiting of feral swine altered areas of utilization, distances from location centroids to treatment location (control or bait station), and movement rates by survivors during culling activities. We hypothesized that the bait station would increase the sedentary nature of feral swine, thus reducing the potential for dispersal and hence disease dispersal. Our experiment was conducted between February and May 2011 on the Rob and Bessie Welder Wildlife Foundation (WWF) in San Patricio County, Texas. We trapped 83 feral swine and placed GPS collars on 21 animals. We established and maintained a centralized bait station on one side of the WWF from 13 March to 27 April. We conducted population-wide culling activities, including trapping, controlled shooting, drive shooting, and aerial gunning, from 3 to 27 April and removed 143 feral swine (4.6feral swine/km(2)). Areas of utilization did not differ between treatments (control or bait station). However, we found location centroids of bait station site feral swine to be closer to the treatment location than those of control site animals and daily movement rates of bait station site feral swine to be 39% greater than movement rates of control site animals. Based on our observation that only 62% of feral swine trapped in proximity to the bait station used it, we cannot recommend baiting as an alternative to fences for containing animals during culling activities. However, there is value in using bait stations to describe patterns of feral swine movements, facilitate observation, and improve efficacy when conducting removals. 相似文献
42.
Maaike C.C. De Graaf Roland Bobbink Nina A.C. Smits Rudy Van Diggelen Jan. G.M. Roelofs 《Biological conservation》2009,142(10):2191-2201
The northwest European heathland landscape with its characteristic communities of nutrient-poor and acidic soils has a high nature value, because of its locally high biodiversity and the distinct site conditions. In order to conserve and restore the heathlands, numerous rehabilitation projects have been performed, although with varying success. This is partly due to the fact that the key biogeochemical processes distinguishing the various vegetation types within the heathlands are not known in detail.Therefore, we performed a statistical survey on the main communities and their soil characteristics. In addition, we analyzed the data for key factors determining biodiversity in the heathland landscape.Data from previous studies and surveys was used to compile a dataset of 267 vegetation relevés (classified as EUNIS habitat types) with extensive soil measurements (22 parameters). A canonical discriminant analysis revealed that soil acidity explained most of the differences between the habitat types, while soil moisture content and soil fertility were less important. Acidity-related factors as Al3+, Al/Ca-ratio and pH were also strongly correlated to plant diversity in the majority of the habitat types, respectively, the species-rich Nardus grasslands, the Rhynchosporion communities and the species-rich Molinia meadows. In the dry heaths and over the total heathland landscape, plant diversity was negatively correlated with soil -concentrations. Only in wet heath, nutrient availability, in this case P, was the primary factor in explaining plant diversity.This study presents ranges for all major soil parameters for the studied well-developed heathland habitat types, thereby providing clear guidelines for conservation and restoration. 相似文献
43.
Cornelis?A.?M.?van?GestelEmail author Maaike?Kruidenier Matty?P.?Berg 《Biology and Fertility of Soils》2003,37(2):115-123
The activities of earthworms, springtails and mites in the decomposition of different substrates were examined by applying three different test methods: wheat straw degradation, the cotton-strip assay and the bait-lamina test. The main aim was to determine the potential of these three methods to describe the (direct and indirect) contribution of soil invertebrates to decomposition processes in soil. Animals were introduced at different densities to mesocosms consisting of intact soil cores taken from grassland. Wheat straw mass loss, determined after 27 days, and cotton tensile strength loss, measured after 14 days, did not significantly differ for the different densities of earthworms, springtails and mites. These findings indicate that cellulose degradation and wheat straw decomposition are more dependent on microbial activity, rather than on the abundance and activity of soil invertebrates. Soil microbial activity, measured as dehydrogenase activity at the end of the 75-day incubation period, did not show any correlation with animal density. Bait-lamina consumption rate was highest for the mesocosms containing earthworms, and increased with increasing earthworm density. Bait-lamina consumption in the mesocosms inoculated with springtails or mites only was not significantly different from that in the controls without animals. In the case of the mites this might at least partly be explained by the low densities used in this experiment. It may be concluded that whilst the bait-lamina test gives the best reflection of the biological activity of soil animals, in particular earthworms, wheat straw and cotton strip decomposition rates are more indicative of microbial activity in the soil. 相似文献
44.
O'Donoghue EM Somerfield SD Shaw M Bendall M Hedderly D Eason J Sims I 《Journal of agricultural and food chemistry》2004,52(17):5383-5390
The storage, soluble, and structural carbohydrates of two onion cultivars, the hard, pungent Pukekohe Longkeeper (PLK) and the softer, milder Houston Grano, were analyzed to determine differences that might be related to their response to sulfur nutrition received during growth as well as their postharvest attributes and end-use suitability. PLK tissue contained 1.37 times more dry matter than Grano and was composed of more fructan and sucrose and less glucose and fructose than Grano [corrected] There were also differences in neutral sugar content, especially galactose, and the amount, size, and content of pectin fractions soluble in chelator and weak alkali. These two onion cultivars differed in their capacity to take up sulfur, but there was no statistical association between sulfur supply and any measured dry matter component. 相似文献
45.
Núbia Rosa da Silva Maaike De Ridder Jan M. Baetens Jan Van den Bulcke Mélissa Rousseau Odemir Martinez Bruno Hans Beeckman Joris Van Acker Bernard De Baets 《Annals of Forest Science》2017,74(2):30