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41.
In recent decades, the Philippines have put much effort into designing strategies for motivating upland communities to plant trees. The accomplishments of these programs have been variable, however, and need further investigation. Focusing on five villages located in the uplands in north-east Luzon, this paper assesses the response to a government program that supplied tenure security to upland farmers in exchange for tree planting, implemented through an NGO project that supported farmers with advice, logistics and free seedlings. Response was measured as the percentage of households that joined the program, the percentage of their lots that they submitted for tenure contract and the percentage of these lots that were actually planted with more than 50 trees. The resulting overall tree adoption rate was that 22% of the lots in the villages had been planted, with a variation of 15–35% between villages. Main motivational factors were the land tenure prospect and the perceived stable markets for fruit and timber. Farmers were not only motivated but also capacitated, both financially and in terms of the bureaucratic procedures, by the NGO project. Without these, the government program could only have benefited the few well-off and educated farmers. The case study stands, therefore, as an example of effective government-NGO partnership. 相似文献
42.
Inge M Krijger Steven R Belmain Grant R Singleton Peter WG Groot Koerkamp Bastiaan G Meerburg 《Pest management science》2017,73(12):2397-2402
Current reactive pest management methods have serious drawbacks such as the heavy reliance on chemicals, emerging genetic rodenticide resistance and high secondary exposure risks. Rodent control needs to be based on pest species ecology and ethology to facilitate the development of ecologically based rodent management (EBRM). An important aspect of EBRM is a strong understanding of rodent pest species ecology, behaviour and spatiotemporal factors. Gaining insight into the behaviour of pest species is a key aspect of EBRM. The landscape of fear (LOF) is a mapping of the spatial variation in the foraging cost arising from the risk of predation, and reflects the levels of fear a prey species perceives at different locations within its home range. In practice, the LOF maps habitat use as a result of perceived fear, which shows where bait or traps are most likely to be encountered and used by rodents. Several studies have linked perceived predation risk of foraging animals with quitting‐harvest rates or giving‐up densities (GUDs). GUDs have been used to reflect foraging behaviour strategies of predator avoidance, but to our knowledge very few papers have directly used GUDs in relation to pest management strategies. An opportunity for rodent control strategies lies in the integration of the LOF of rodents in EBRM methodologies. Rodent management could be more efficient and effective by concentrating on those areas where rodents perceive the least levels of predation risk. © 2017 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. 相似文献
43.
Jeroen C.J. Groot André Jellema Walter A.H. Rossing 《European Journal of Agronomy》2010,32(1):112-119
Spatial planning aimed at multifunctional agriculture can be seen as a negotiation process on environmental, social and economic aspects of land use. Complexity arises due to the high number of stakeholders and due to the limited knowledge, which is often organized along disciplinary divides. This paper sets out from the premise that the role of agronomy in such land use planning processes can be strengthened by approaches that allow multi-objective and multi-scale evaluation of spatially explicit land use alternatives. We present an application of the explorative Landscape IMAGES framework, which employs the Differential Evolution optimization strategy and the concepts of Pareto optimality that are relatively easy to implement and to combine with spatially explicit indicator assessments. This technique yields a set of solutions, each representing a spatial configuration of hedgerows in a landscape along with the performance of the landscape in terms of Pareto rank and efficiency. The methodology was applied in a redesign of the structure of linear landscape elements in an agri-ecological zone in The Netherlands where 7 indicators representing ecological quality, landscape character and implementation costs were considered. The case study was developed in interaction with an NGO involved in landscape management planning and implementation.Spatial cohesion in the landscape was found to increase with larger total hedgerow length, but could also be improved without increasing the total length (and therefore costs of establishment and maintenance). Trade-offs existed with other objectives, since this change would involve replacing hedgerows currently positioned in the longitudinal direction (L) of the fields by hedgerows in the transversal direction (T). This change would compromise cultural heritage value as expressed in the L/T ratio, and it would require removal of mature hedgerows in some places and adding of new hedgerows elsewhere in the landscape, thereby increasing implementation costs.The approach was evaluated positively in terms of design validity, output validity and end-user validity. The role of the Landscape IMAGES framework in setting a research agenda to enhance the role of agronomy in multifunctional land use planning is discussed. 相似文献
44.
Ton?i Rezi? Michaela Zeiner Bo?idar ?antek Sr?an Novak 《Water, air, and soil pollution》2011,214(1-4):343-355
Mixed microbial culture was isolated from heavy metal-contaminated ground soils located inside iron, vinyl and cement factory area. Isolated mixed microbial culture was used for the heavy metal ions (Fe2+, Cu2+, Ni2+ and Zn2+) removal process in horizontal rotating tubular bioreactor (HRTB). In this research, the effect of bioreactor process parameters on the bioprocess dynamics in the HRTB was studied. Results of this research have shown that profiles of heavy metals concentration were gradually reduced along HRTB at all combinations of bioreactor process parameters [inflow rates (0.5?C2.0 L?h-1) and rotation speed (5?C30 min-1)]. Hydrodynamic conditions and biomass sorption capacity have main impact on the metal ions removal efficiency that was varied in the range of 38.1% to 95.5%. Notable pH gradient (cca 0.7 pH unit) along the HRTB was only observed at the inflow rate of 2.0 L?h-1. On the basis of obtained results, it is clear that medium inflow rate (F) has higher impact on the heavy metal removal process than bioreactor rotation speed (n) due to the fact that increase of inflow rate was related to the reduction of equilibrium time for all examined metal ions. Furthermore, equilibrium times for all metal ions are significantly shorter than medium residence times at all examined combinations of bioreactor process parameters. The main impact on the biofilm sorption capacity has covalent index of metal ions and biofilm volumetric density. The sorption capacity of suspended microbial biomass is closely related to its concentration. Results of this research have also shown that the removal of heavy metals ion can be successfully conducted in an HRTB as a one-step process. 相似文献
45.
Federico Tinivella Lucia M. Hirata Mikael A. Celan Sandra A. I. Wright Tahsein Amein Annegret Schmitt Eckhard Koch Jan M. van der Wolf Steven P. C. Groot Dietrich Stephan Angelo Garibaldi Maria Lodovica Gullino 《European journal of plant pathology / European Foundation for Plant Pathology》2009,123(2):139-151
Greenhouse trials were carried out in order to test the efficacy of different seed treatments as alternatives to chemicals
against Colletotrichum lindemuthianum cause of anthracnose on bean and Ascochyta spp. cause of Ascochyta blights on pea, respectively. Resistance inducers, commercially formulated microorganisms, non-formulated
selected strains of different microorganisms (fungi, bacteria and yeasts) and plant extracts were applied as dry or liquid
seed treatments on naturally infested seeds. Seedling emergence and disease incidence and/or severity were recorded. Almost
all seed treatments turned out to be ineffective in controlling the Ascochyta infections, which is in line with the literature
stating that these pathogens are difficult to control. The only alternative treatments that gave some control of Ascochyta spp. were thyme oil and a strain of Clonostachys rosea. The resistance inducers tested successfully controlled infections of bean by C. lindemuthianum. Among the formulated microorganisms, Bacillus subtilis-based formulations provided the best protection from anthracnose. Some strains of Pseudomonas putida, a disease-suppressive, saprophytic strain of Fusarium oxysporum and the mustard powder-based product Tillecur also proved to be effective against bean anthracnose. However, among the resistance
inducers as well as among the other groups, certain agents caused a significant reduction of plant emergence. Different alternative
seed treatments can therefore be used for the control of C. lindemuthianum on bean, while on pea only thyme oil and a strain of Clonostachys rosea showed some effectiveness against Ascochyta spp. 相似文献
46.
47.
Abstract— The clinical and histopathological features of discoid lupus erythematosus (DLE) are described in four European short-haired cats. Pinnal involvement seems to be highly predictable in feline DLE. In addition an indication exists for the initiating role of exposure to the sun in this disease. Résumé— Les aspects cliniques et histopathologiques du lupus érythémateux discoide (DLE) sont décrits chez quatre chats européens à poils courts. L'atteinte du pavilion auriculaire semble très fréquente dans le DLE félin. En outre, l'exposition au soleil semble jouer un röle déterminant dans cette entité nosologique. Zusammenfassung— Die klinischen und histopathologischen Merkmale des diskoiden Lupus erythematosus (DLE) bei vier Europäisch-Kurzhaarkatzen werden beschrieben. Beim felinen DLE scheint die Pinna regelmäßig mitbetroffen zu sein. Nach dieser Untersuchung besteht Anlaß zur Vermutung, daß die Sonnenexposition bei dieser Krankheit eine auslösende Rolle spielt. 相似文献
48.
‘De Groene Vlieg’ (the Green Fly) is an independent company offering various services concerning integrated pest management in open field agriculture in the Netherlands. One such service is the supervised control of carrot fly (Psila rosae). From 1993 to 2008 the company has monitored the carrot fly population on a total of nearly 65 000 hectares resulting in an extensive dataset. The data was not collected according to proper experimental methods, hence it is titled dirty, but the size of the dataset does allow valuable insights to be gained. De Groene Vlieg monitors the carrot fly population on each field separately. Sticky traps are collected weekly and flies are counted in the laboratory. Growers receive messages containing advice regarding when to apply insecticides and they are responsible for doing so. Overall, over a third of the fields require no spraying at all and for 75% of the fields growers are advised to spray three times or less. One insight from the dataset is that small carrots require more insecticide treatments than large carrots (‘winter carrots’). Reasons for this difference are probably both regional and cultural. Additionally, focusing on a small and uniform area reveals that carrot fly population dynamics are highly variable between years. Another insight is that sowing date has a large effect on the number of insecticide sprayings that are required. Fields sown before the first flight have more flies in the second flight than fields sown later. Comparison of biological and conventional carrot fields shows that carrot fly populations are similar for the first flight. However, during the second flight the number of flies is much higher on organic fields than on conventional ones. Finally, insecticide seed treatment with chlorfenvinphos to control the reproduction of the first flight appears slightly more efficient than supervised control. However, supervised control seems as efficient as seed treatment with clothianidin and beta cyfluthrin. 相似文献
49.
50.