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41.
G. Moreno S. Aviron S. Berg J. Crous-Duran A. Franca S. García de Jalón T. Hartel J. Mirck A. Pantera J. H. N. Palma J. A. Paulo G. A. Re F. Sanna C. Thenail A. Varga V. Viaud P. J. Burgess 《Agroforestry Systems》2018,92(4):877-891
Land use systems that integrate woody vegetation with livestock and/or crops and are recognised for their biodiversity and cultural importance can be termed high nature and cultural value (HNCV) agroforestry. In this review, based on the literature and stakeholder knowledge, we describe the structure, components and management practices of ten contrasting HNCV agroforestry systems distributed across five European bioclimatic regions. We also compile and categorize the ecosystem services provided by these agroforestry systems, following the Common International Classification of Ecosystem Services. HNCV agroforestry in Europe generally enhances biodiversity and regulating ecosystem services relative to conventional agriculture and forestry. These systems can reduce fire risk, compared to conventional forestry, and can increase carbon sequestration, moderate the microclimate, and reduce soil erosion and nutrient leaching compared to conventional agriculture. However, some of the evidence is location specific and a better geographical coverage is needed to generalize patterns at broader scales. Although some traditional practices and products have been abandoned, many of the studied systems continue to provide multiple woody and non-woody plant products and high-quality food from livestock and game. Some of the cultural value of these systems can also be captured through tourism and local events. However there remains a continual challenge for farmers, landowners and society to fully translate the positive social and environmental impacts of HNCV agroforestry into market prices for the products and services. 相似文献
42.
Yellowwood (Cladrastis kentukea) grows in small, widely scattered populations in the wild, but is also a popular ornamental tree that thrives when planted in urban areas outside its natural range. Since the small native populations of yellowwood in several states are considered at risk of extirpation, the cultivated population could serve as an ex situ repository of yellowwood genetic diversity that could be used to restore lost local populations of the species. The potential value of cultivated yellowwood for conservation depends on the genetic diversity among cultivated trees compared to natural populations. Using nuclear microsatellite markers, we genotyped 180 yellowwoods from natural populations in Indiana, Missouri, Arkansas, and Kentucky, along with 61 trees from urban parks and landscapes in Indiana, Ohio, and Missouri. We found that, even when statistics were adjusted based on population size, the urban “population” had higher genetic diversity than any of the wild populations sampled, indicating that commercially-grown yellowwood is most likely a mixture of genotypes from isolated wild populations. We observed strong genetic differentiation among wild populations, and evidence for inbreeding in at least one of the wild populations. 相似文献
43.
Baumgartner C Bollerhey M Ebner J Laacke-Singer L Schuster T Erhardt W 《Canadian journal of veterinary research》2010,74(3):200-208
The direct effects of ketamine-xylazine (KET-XYL) on vascular function have not been investigated in rabbits. The short-term cardiovascular effects of intravenous (IV) KET-XYL bolus injection, therefore, should be investigated using vascular ultrasonography.In this prospective experimental study, KET-XYL anesthesia was induced IV in 9 female New Zealand White rabbits before 3 defined test bolus injections of KET-XYL were given IV. Before and for 10 min after each KET-XYL injection vascular and hemodynamic variables were recorded at the left common carotid artery (ACC) after the 1st injection, and at the abdominal aorta (AA) after the 2nd injection. Echocardiography was performed after the 3rd injection to investigate changes in cardiac parameters.Ketamine-xylazine IV caused a significant increase in vessel diameter at the ACC and AA. Average volumetric flow significantly decreased at the ACC and pulsatility index significantly decreased at the AA. Fractional shortening (FS) and heart rate significantly decreased, while mean arterial blood pressure initially increased.Bolus injections of KET-XYL IV produced a transient vasodilatation at the ACC and AA. Despite central vasodilatation, bradycardia, and decrease of FS and average volumetric flow (VFave), mean arterial blood pressure did not significantly decrease indicating well-preserved cardiovascular compensatory mechanism after the ratio and doses of KET-XYL IV bolus injections used in this study. 相似文献
44.
Effects of urbanization on ground-dwelling spiders (Araneae) were studied using pitfall traps along an urban-suburban–rural
forest gradient in Debrecen (Hungary). We found that overall spider species richness was significantly higher in the urban
sites compared to the suburban and rural ones. The increased diversity was due to the significantly more open-habitat species
in the assemblages at the urban sites. This suggests that species from the surrounding matrix (grasslands and arable lands)
penetrated the disturbed urban sites. The ratio of forest species was significantly higher in the rural sites than in the
suburban and urban ones, suggesting that forest species are indeed sensitive to the disturbance caused by urbanization. Canonical
correspondence analysis revealed that the species composition changed remarkably along the urbanization gradient. Open-habitat
spiders were associated with the urban sites of higher ground and air temperature. Forest spiders were characteristic of the
rural sites with higher amount of decaying woods. Our findings suggest that the overall diversity was not the most appropriate
indicator of disturbance; species with different habitat affinity should be analyzed separately to get an ecologically relevant
picture of the effect of urbanization. 相似文献
45.
Márk Rékási Tibor Szili-Kovács Tünde Takács Botond Bernhardt Ildikó Puspán Rita Kovács 《Archives of Agronomy and Soil Science》2019,65(1):44-57
Achieving a sustainable increase in the fertility of sandy soils is a major problem. The application of biochar (BC) is a relatively new method, but results for a temperate climate are scarce. This work investigates various combined doses of BC and plant growth-promoting rhizobacteria inoculants on the fertility of acidic and calcareous sandy soils, hypothesising that joint application could have a synergistic impact. The effects were followed by measuring chemical (pH, organic matter, nutrient availability) and microbiological properties of the soil and maize biomass. 30 t ha?1 BC increased both pH (by 1 unit) and nitrification in acidic soil (causing a 60% drop in NH4-N concentration), and the phosphorus and potassium availability (by 53 and 80%, respectively) in both soils. Substrate-induced respiration increased by up to 100% and 50% in acidic and calcareous soil, respectively, in treatments involving both BC and inoculant. In acidic soil a BC dose of 3 t ha?1 resulted in a 70% decrease in arbuscular mycorrhizal fungal infection. Changes in maize grain yield were not significant, but the increase in above-ground biomass indicated that the combined application of BC and inoculant is more beneficial than separate application of these yield-increasing agents, primarily on acidic sand. 相似文献
46.
Thomas Eckert Mahena Jhrling-Butkus Helen Louton Monika Burg-Roderfeld Ruiyan Zhang Ning Zhang Karsten Hesse Athanasios K. Petridis Tibor Kor Jürgen Steinmeyer Roland Schauer Peter Engelhard Anna Kozarova John W. Hudson Hans-Christian Siebert 《Marine drugs》2021,19(10)
Osteoarthritis belongs to the most common joint diseases in humans and animals and shows increased incidence in older patients. The bioactivities of collagen hydrolysates, sulfated glucosamine and a special fatty acid enriched dog-food were tested in a dog patient study of 52 dogs as potential therapeutic treatment options in early osteoarthritis. Biophysical, biochemical, cell biological and molecular modeling methods support that these well-defined substances may act as effective nutraceuticals. Importantly, the applied collagen hydrolysates as well as sulfated glucosamine residues from marine organisms were strongly supported by both an animal model and molecular modeling of intermolecular interactions. Molecular modeling of predicted interaction dynamics was evaluated for the receptor proteins MMP-3 and ADAMTS-5. These proteins play a prominent role in the maintenance of cartilage health as well as innate and adapted immunity. Nutraceutical data were generated in a veterinary clinical study focusing on mobility and agility. Specifically, key clinical parameter (MMP-3 and TIMP-1) were obtained from blood probes of German shepherd dogs with early osteoarthritis symptoms fed with collagen hydrolysates. Collagen hydrolysate, a chondroprotective food supplement was examined by high resolution NMR experiments. Molecular modeling simulations were used to further characterize the interaction potency of collagen fragments and glucosamines with protein receptor structures. Potential beneficial effects of collagen hydrolysates, sulfated glycans (i.e., sulfated glucosamine from crabs and mussels) and lipids, especially, eicosapentaenoic acid (extracted from fish oil) on biochemical and physiological processes are discussed here in the context of human and veterinary medicine. 相似文献
47.
Viruss damage was observed on plants of Lolium perenne L. and Dactylis glomcrata L. undergoing growth-analysis studies. On the basis of visual symptoms the damage was presumed to be caused by barley-yellow-dwarf virus (BYDV) in ryegrass and by streak virus (CSV) in cocksfoot. The number of plants which could be clinically diagnosed as infected and the degree of damage were both positively correlated with temperature. It was inferred that at low temperatures both viruses could remain relatively inactive, or even latent. This was subsequently confirmed by removing cocksfoot plants from a heated glasshouse (19°–23°C) to a cold environment (6–10°C) which resulted in a progressive loss of symptoms in newly developing leaves. Some possible explanations and practical implications are briefly discussed. 相似文献
48.
OBJECTIVE: Comparison of 2 methods of surgical management of cranial cruciate ligament (CCL) injury in large-breed dogs using a radiographic osteoarthrosis (OA) scoring system. STUDY DESIGN: Retrospective study. ANIMALS: Client-owned dogs (n=66). METHODS: Radiographs were evaluated from dogs weighing >/=22.7 kg, with surgical management of CCL rupture using extracapsular repair (ECR) or tibial plateau leveling osteotomy (TPLO). Radiographs were taken immediately before surgery and >/=12 months later. An OA score was assigned to each set of radiographs taken at the preoperative and final examinations by evaluating 32 specific features of stifle OA. The difference between preoperative and final OA scores were subtracted and 2 final score categories of a change =5 or >5 were created. A logistic regression model was used to evaluate the effect of right versus left pelvic limb, age, preoperative weight, postoperative weight, days from surgery until final radiographic recheck, cranial cruciate status at surgery, medial meniscus status at surgery, and ECR versus TPLO. RESULTS: The ECR group had 27 stifles (22 dogs) and the TPLO group had 52 stifles (44 dogs). ECR dogs had a preoperative weight of 33.4+/-9.3 kg (range 22.7-54.1 kg) and a preoperative OA score of 13.0+/-8.4 (range 1-34) compared with TPLO dogs that had a preoperative weight of 38.9+/-9.1 kg (range 25-63.9 kg) and preoperative OA score of 15.9+/-8.4 (range 4-44). Postoperative weights for ECR and TPLO dogs were 33.6+/-9 kg (range 21.8-54.6 kg) and 39.4+/-10.1 kg (range 24-72 kg), respectively. Final OA scores were: ECR dogs, 26.3+/-10.8 (range, 10-54); TPLO dogs, 23.3+/-9.5 (range, 12-50). Dogs with a final change in OA score of >/=6 were 5.78 times more likely to have had ECR compared with those that had TPLO as stabilization procedure (odds ratio=5.78; Log-likelihood test P-value=.025). Other dependent variables were not significant. CONCLUSIONS: Based on logistic regression analysis, dogs with larger OA score differences were 5.78 times more likely to have had ECR than TPLO. CLINICAL RELEVANCE: Prospective, randomized surgical trials with pre-defined objective measures would be required to further evaluate the clinical importance of these preliminary findings which suggest that TPLO may help stabilize the cranial tibial thrust as originally proposed. 相似文献
49.
50.
In a model experiment, Holstein-Friesian dairy cows were fed on a corn-silage-based diet supplemented with 11.75 MJ NE1 per day of calcium soaps of palm oil fatty acids (CAS) or hydrogenated triglyceride (HTG) or without fat supplementation (control). All diets were fed to the cows over a period from 21 +/- 3 days (d) prior to the expected calving to d 100 +/- 5 postpartum. On d 25 (basal sample) and d 14 prepartum as well as on d 5 and 25 postpartum liver samples were collected by percutaneous biopsy. Total lipid content, fatty acid composition and glycogen of liver tissues were determined. At d 5 postpartum, both control and CAS cows had higher liver lipid (P < 0.05) and lower glycogen (P < 0.05) concentrations than cows in the HTG group. No significant (P < 0.05) differences were detected in liver fat content among the groups at d 14 prepartum or d 25 postpartum. The glycogen concentration slightly decreased in the liver of cows in each treatment group from d 14 prepartum to d 5 postpartum; however, this decrease was more intensive in both the control and CAS groups than in the HTG group. The variations in liver lipid concentrations were accompanied by significant changes in the proportion of C16:0, C16:1n-7, C18:0, C18:1n-9, C18:2n-6 and C20:4n-6 fatty acids in the liver lipids. The results show that HTG supplementation exerted more advantageous effects on liver lipid and glycogen metabolism than did CAS supplementation. 相似文献