Eared Dove, Southern Lapwing, Chimango Caracara, Rufous-collared Sparrow are species commonly found in agroecosystems and urban areas . Interestingly, abundance of Eared Dove and Chimango caracara were negatively related to the proportion of fragments but positively associated to the presence of fragments, indicating that even small fragments could be favor these species. Plot and landscape scale were important for conservation within this agroecosystem . This result indicated that both core areas of native vegetation as well as fragments of native vegetation within vineyards are necessary to enhance birds in agroecosystem. My results agree in part with others findings that the plot scale are more relevant for predicting distribution of birds in agroecosystem . Landscape scale was important for some communities as for granivores, indicating that multiple scales should be considered for this study area. My findings also coincide others highlighting the significance of small structural features such as single trees or hedgerows for increase birds within agroecosystems . This could be related to agriculture is a recent driver of land use change in comparison with other regions such as Europe where agriculture has a long history of habitat modification . These results should be interpreted in light of study limitations. Firstly, I did not measure micro-scale variables, as inter row cover crops or bare soil, that could shape bird communities in vineyards . However, previous research showed that these variables could be more significant during winter and not for the reproductive season in central Chile . Secondly, I did not assess the influence of the agricultural management as a covariate with bird abundance. Our study design cannot disentangle the interactions between agricultural management and landscape complexity.
Indeed,30 litre plant pots some of the vineyards that present high landscape complexity were managed conventionally while other vineyards that were managed organically presented low landscape complexity or were surrounded by other crops . Recent literature reveals that in highly mobile species such as birds, the proportion of natural vegetation within the landscape appears to be more relevant than conventional/organic management . Conservation of Forest-Matorral will play a fundamental role for the dynamics of whole bird communities. Given the potential for habitat fragments in and around the vineyard to enhance bird composition across the vineyard landscape and the fact that these fragments can be easily maintained or restored within vineyards, at low economic cost for vineyard production, I propose that maintaining and restoring fragments of native habitat should be widely adopted by grape growers . Restoration approaches should vary depending on the conservation goal. For example, in order to increase the potential ecosystem services provided by insectivore birds, fragments and large areas or Forest-Matorral are essential for a landscape planning in this area. In contrast, in order to conserve endemic rhynocriptids, preserving and restoring large areas of native vegetation is crucial. Most Scleorphyllous forest and Chilean Matorral is located in private sector, and the majority of the vineyards participating in this research own adjacent hills with native vegetation. A lack of policies and incentives that promote conservation of these ecosystems is still a challenge. Recently, laws approved by the Chilean parliament favor private parks, but incentives for conservation are still poor, with a lack of practical legal recognition and depend on individual species preferences by landowners . Simultaneously, land use change by vineyards is a continuous threat for wild areas due to continuous growth trends in the last 30 years .
Vineyard industry sales are valued at US $2,200 million for the year 2011 and projected to reach US $4,500 million in 2020 . The main driver of this industry is international market demand . Lack of land planning and restrictions to agricultural expansion are not currently part of the Chilean economic growth model . However, consumers demand could play a significant role in driving wine industry innovation toward a more sustainable arena . Strategies that preserve and restore fragments of native vegetation and core areas within vineyards can provide a successful approach for bird conservation in Chilean agroecosystems. Agricultural water districts are perhaps the most important players in efforts to reform water-resource management in California. According to several observers, a key impediment to the evolution of California water markets is the requirement in state law that water districts must approve any transfer of water rights outside of their borders . Agricultural irrigation districts have been particularly reluctant to participate in sales that would apparently transfer water from low-valued agricultural uses to higher-valued urban and industrial consumption. How these districts might distribute the costs and benefits associated with these trades has been the focal point of removing this particular barrier to developing viable water markets . In addition, the 1992 Central Valley Project Improvement Act focused on water districts as the agents for implementing water conservation and efficiency measures . On the other hand, recent attempts to establish water market protocols in California that bypass district control have met stiff resistance to date from agricultural interests. 1 Proposals by economists to reform water-resource management and to develop water markets generally have not considered the institutional context in which the targeted agricultural districts operate. Most analyses of water rights markets assume that the participants are attempting to gain the maximum net profits or monetary benefits.
However, this presumption may be off target, particularly if public-enterprise agencies dominate the water management structure as is the case in California. Given that most future water transfers in California are likely to occur among public agencies, looking beyond typical neo-classical assumptions about the “theory of the firm” may be important to understanding how water markets might develop . Previous political economy studies of irrigation districts have looked at some of aspects of how district decision-making processes work , but none has examined California districts across political structures in an economic framework. The emergence of two recent issues adds to the importance of better understanding the incentives embodied in various water-district forms. The first is that use of any electoral system other than universally-enfranchised, popular-vote was challenged successfully in part in federal court . The Association of California Water Agencies intervened with an amicus curiae brief to defend the voting system now in use in California water districts . The second is the recent passage of Proposition 218 in November 1996. This new law requires in many instances that certain types of special-purpose taxes must be approved by a majority vote of the assessed-benefit, and fees and charges by a majority of “property owners” within the relevant jurisdiction . Many of the dynamics that now affect water districts using”assessed-value voting will come to bear in a larger context among many local governments.The one example of a political-science study examined how the various electoral rules affected voter participation . The authors, in a report done for the California Department of Water Resources, attempted to explain why property-based rules led to less “democratic” processes than the popular-based methods. Unfortunately,25 liter pot plastic the predictive theory was unclear in the analysis, and the statistical analysis did not strongly support the thesis. Two comparative studies used sociological methods. Coontz examined the historical development of the Kings River Water Association and maintains that districts single-rnindedly pursued physical acquisition and control of water rights either through construction of diversion facilities or by appealing to outside government agencies for assistance in funding of upriver storage structures . Eventually, a strong contractual arrangement was structured, and the previously strife-torn parties successfully stood in concert against the U.S. Bureau of Reclamation during contract negotiations. In the Grasslands Area, Coontz found that the legacy of Miller-Lux had left control of the region’s water rights and leadership role to the Central California Irrigation District . As part of the Miller-Lux operations, neighboring farmers were allocated water portions greater than they might have achieved in fighting MillerLux and losing. This cooperative arrangement among districts and farmers continues today. Both of these situations represent bargaining solutions driven by the perceived disagreement outcomes by each party. In the first case, the upstream districts could physically control the flow of the Kings River, while the downstream Tulare Lake farmers could appeal to outside political power in the USBR and the city of Los Angeles.
The result was a hard-driven bargain that required strictly defined behavior. In the second case, Miller-Lux, and later CCID, controlled the lion’s share of local water rights. As a result, its neighbors were quite willing to accept a cooperative rather than confrontational solution since they could face substantial losses if they defected. The classical paradigm in which the district maximizes the total net benefits of all members is the most frequently seen in the economic literature. In each case, the water district is entirely transparent to the motives of the farmers themselves. In other words, these models simply assume that district managers use maximizing aggregate net income as their objective function. The district managers have no individual motives themselves nor do they consider any other objectives than resource-use efficiency. The three more recent political-economy models approach differently the question of how districts’ policies are chosen . The first two models treat the institutional management-selection rules as the focal point of policy decisions, while the latter one examines the importance of informal political influence. The first and third models put the districts’ managers at the center of the decision making process, while the second one implies that decisions directly reflect the wishes of the districts’ members. The latter two models rely on information about individual members within each district, either about farming activities or relative political influence. None of the models assume that a district manager maximizes the total net benefits to member, but rather coalitions are built by targeting benefits to certain groups within a district. In the first model, district managers attempt to maximize district profits while maintaining a sufficient level of voting support in a median-voter or “isoprofit/isovote” model . This model focuses on managers as the decision-making unit. Unfortunately, McDowell, did not adequately specify the empirical model to give meaningful empirical results. In the second model, management policies are chosen based on which policy draws the greatest political support among the district’s members, which is done by comparing the relative economic benefits that each would receive . This approach views the members’ operations as the units of analysis and aggregates to the district level. The model sees the managers as simply transparent to the decision-making process. In the third model, the district managers attempt to maximize the benefits of the members subject to a distribution based on the relative political strengths of each member . This model examines the motives of both the managers and members and creates a two-stage optimization model, McDowell, examine whether government-enterprise managers respond to the sometimes divergent interests of “voter-consumers” in a manner different from those of private enterprises . Public managers must balance maintaining political support that ensures their tenure with maximizing net benefits to consumers of the districts’ services. The analytic framework uses the median-voter paradigm . M&U hypothesize that if political support is not proportional to revenue responsibility, i.e., the districthas many voters of whom few pay related fees or taxes, then interests diverge between the disparate groups within the district, They further ask whether cross-subsidies through pricing are more likely in the case of government enterprises. M&U build on Peltzman’s model in which the district manager attempts to maximize voter support subject to the constraint that total district benefits exceed a certain level . The dual of this problem is to minimize the economic benefits forgone to achieve a majority vote. The result is finding the tangency of the isovote and isoprofit curves in the multiple-group/price space. The isovote curve represents the combination of prices to the relevant groups within the district that maintain the same level of political support. The isoprofit curve represents the combination of prices to the relevant groups within the district that maintain the same level of total net benefits to the district. If the political process transmits voter support in proportion to the revenues generated by the consumers in each group, then the tangency should lie along the 45 degree line from the origin, Le., the relative prices for each group should be the same.