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This paper examines the possibilities of developing agri-environmental policy measures in Israel, focusing on market-oriented instruments. A conceptual framework for developing agri-environmental policy measures is presented, first in very broad lines (mandatory regulations, economic instruments and advisory measures) and subsequently focusing on economic instruments, and specifically, on market-oriented ones. Two criteria of choice between the measures are suggested: their contribution to improving the effectiveness of the policy; and the feasibility of their implementation. This is the framework used for analyzing agri-environmental measures in Israel. Israel currently implements a mix of mandatory regulations, economic instruments and advisory measures to promote the agri-environment. The use of additional economic instruments may improve the effectiveness of the policy. When comparing the effectiveness of various economic measures, we found that the feasibility of implementation of market-oriented instruments is greater, due to the Israeli public’s preference for strengthening market orientation in the agricultural sector. Four market-oriented instruments were practiced in a pilot project conducted in an Israeli rural area. We found that in this case study, the institutional feasibility and acceptance by stakeholders were the major parameters influencing the implementation of the market-oriented instruments, whereas the instruments’ contribution to enhancing the ecological or economic effectiveness were hardly considered by the stakeholders as arguments in favor of their use.  相似文献   
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In Brazil’s semi-arid Northeast, most rural dwellers derive income from the dry Caatinga forest through livestock farming, fruit collection, and firewood extraction. However, recurring droughts and inadequate land use practices jeopardize farmers’ livelihoods. The drought-resistant, endemic Umbuzeiro tree provides fruit for direct consumption and allows for the creation of transformed products. The planting of this native species can enhance the well-being of the ecosystem and establish future benefits for smallholdings. However, it is crucial that when taking up innovative practices to cope with environmental change, a willingness to apply them should be fostered among local farmers. We used constellation analysis as a transdisciplinary approach to identify elements of current land management which subsequently defined the nodes of a Bayesian network (BN). We developed probabilities of practice uptake that strengthen success, namely the conservation of natural resources while securing the incomes of smallholders. In collaboration with stakeholders and experts, 25 identified nodes for the BN were tested under various scenarios. Adopting all suggested innovative practices secures the final objectives—ecosystem health and farmer benefits (approx. 90%). The analysis quantified the relevance of single issues that may impede farmers to adopt the practices, such as having to cultivate seedlings or avoiding long-term investments. Further crucial actions include the fencing-off of livestock and marketing pathways. Affordable credit, research, and supportive farmers’ institutions can encourage farmers to implement innovative practices. The use of modeled scenarios can provide evidence, which might encourage sustainable land management.  相似文献   
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Summary. Soil organisms in direct and indirect interaction with plant roots affect aboveground herbivores, likely by inducing different plant responses. We investigated the combined effects of the root-knot nematode Meloidogyne incognita (in direct interaction with roots) and the endogeic earthworm Octolasion tyrtaeum (in indirect interaction with roots) on the performance of Brassica oleracea. Both earthworms and nematodes increased N uptake and shoot biomass of B. oleracea. Earthworm activity mobilized more soil N than litter N, and herbivory by nematodes tended to increase the microbial biomass in soil. Only the structural class of sulphur containing glucosinolates was affected by the soil organisms. Earthworms decreased glucoiberin concentrations in B. oleracea shoots. Glucoraphanin was affected by an interaction between earthworms and nematodes.  相似文献   
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Forest encroachment threatens the biological diversity of grasslands globally. Positive feedbacks can reinforce the process, affecting soils and ground vegetation, ultimately leading to replacement of grassland by forest species. We tested whether restoration treatments (tree removal, with or without fire) reversed effects of nearly two centuries of encroachment by Abies grandis and Pinus contorta into dry, montane meadows in the Cascade Range, Oregon, USA. In nine, 1-ha plots containing a patchy mosaic of meadow openings and forests of varying age (20 to > 140 yr), we compared three treatments affecting the ground vegetation: control (no trees removed), unburned (trees removed, slash burned in piles leaving 90% of the area unburned), and burned (trees removed, slash broadcast burned). We quantified changes over 3-4 years in soils, abundance and richness of species with differing habitat associations (meadow, forest, and ruderal), and recruitment of conifers. Except for a transient increase in available N (especially in burn scars), effects of burning on soils were minimal due, in part, to mixing by gophers. Tree removal greatly benefited meadow species at the expense of forest herbs. Cover and richness of meadow species increased by 47% and 38% of initial values in unburned plots, but changed minimally in burned plots. In contrast, cover and richness of forest herbs declined by 44% and 26% in unburned plots and by 79% and 58% in burned plots. Ruderal species and conifer seedlings were uncommon in both treatments. Although vegetation was consumed beneath burn piles, meadow species recovered significantly after three years. Long-term tree presence did not preclude recovery of meadow species; in fact, colonization was greater in older than in younger forests. In sum, temporal trends were positive for most indicators, suggesting strong potential for restoration. Contrary to conventional wisdom, tree removal without fire may be sufficient to shift the balance from forest to meadow species. In meadows characterized by historically infrequent fire, small-scale disturbances and competitive interactions may be more critical to ecosystem maintenance and restoration. Managers facing the worldwide phenomenon of tree invasion should critically evaluate the ecological vs. operational need for fire in ecosystem restoration.  相似文献   
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