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121.
Assessing Integrated Pest Management Adoption: Measurement Problems and Policy Implications 总被引:1,自引:0,他引:1
For more than a decade, the U.S. government has promoted integrated pest management (IPM) to advance sustainable agriculture.
However, the usefulness of this practice has been questioned because of lagging implementation. There are at least two plausible
rationales for the slow implementation: (1) growers are not adopting IPM—for whatever reason—and (2) current assessment methods
are inadequate at assessing IPM implementation. Our research addresses the second plausibility. We suggest that the traditional
approach to measuring IPM implementation on its own fails to assess the distinct, biologically hierarchical components of
IPM, and instead aggregates growers’ management practices into an overall adoption score. Knowledge of these distinct components
and the extent to which they are implemented can inform government officials as to how they should develop targeted assistance
programs to encourage broader IPM use. We address these concerns by assessing the components of IPM adoption and comparing
our method to the traditional approach alone. Our results indicate that there are four distinct components of adoption—weed,
insect, general, and ecosystem management—and that growers implement the first two components significantly more often than
the latter two. These findings suggest that using a more nuanced measure to assess IPM adoption that expands on the traditional
approach, allows for a better understanding of the degree of IPM implementation. 相似文献
122.
Nicole E. Phillips 《Marine Biology》2011,158(10):2335-2342
This study evaluated whether larvae of the Indo-Pacific vermetid gastropod Dendropoma maximum are obligate planktotrophs, or whether they exhibit an intermediate feeding strategy. Experiments were conducted in Moorea,
French Polynesia (149°50′W, 17°30′S), Sep–Oct 2009, to examine D. maximum larval growth and metamorphic responses to different diets and amounts of food. Dendropoma maximum larvae required particulate food to undergo metamorphosis, but were able to survive and grow in the absence of food for up
to 20 days. Larvae in Low and Unfed food treatments exhibited phenotypic plasticity by growing a larger velum (the larval
feeding structure) compared with those in high food. Unfed D. maximum larvae had a slower initial growth rate; however, by 11-day post-hatch fed and unfed larvae had converged on the same mean
shell height (553 μm), which was only 10% larger than the initial size at hatching. Therefore, although the nutritional strategy
of D. maximum larvae is best described as obligate planktotrophy, it appears to approach an intermediate feeding strategy. 相似文献
123.
Is ISO 14001 a gateway to more advanced voluntary action? The case of green supply chain management 总被引:1,自引:0,他引:1
Toshi H. Arimura Nicole Darnall 《Journal of Environmental Economics and Management》2011,61(2):170-182
Using Japanese facility-level data, we estimate the effects of ISO 14001 certification on the promotion of more advanced practices, namely green supply chain management (GSCM). Our results show that ISO 14001 promotes GSCM practices. Facilities with environmental management systems (EMS) certified to ISO 14001 are 40% more likely to assess their suppliers' environmental performance and 50% more likely to require that their suppliers undertake specific environmental practices. Further, government programs that encourage voluntary EMS adoption indirectly promote GSCM practices. These programs increase the probabilities that facilities will assess their suppliers' environmental performance and require suppliers to undertake specific environmental practices by 7% and 8%, respectively. Combined, these findings suggest that there may be significant but previously unnoticed spillover effects of ISO 14001 and government promotion of voluntary action. 相似文献
124.
A marine spatial planning (MSP) initiative—if to be successful—has to be rooted in a thorough understanding of the tradition
and structures of the governance system in the area targeted for the initiative. After decades of a mainly sectoral approach
towards maritime affairs, governments began to recognised the need for a governance framework that applies a more integrated
approach to maritime policy. The new Integrated Maritime Policy of the European Union is only one example for such a changed
way of policy and decision making. The assembly of a governance baseline can help to identify the crucial hindering and success
factors for the implementation of MSP. A governance baseline has two parts. Part One focuses upon the past and current performance
of the governance system as it has responded—or failed to respond—to changes in the condition of ecosystems in a specific
locale. Part Two of a baseline outlines a strategic approach to the design of a new program and records the goals, objectives
and strategies of MSP implementation. Focus on both governance processes and their outcomes is essential and forms the core
justification for documenting governance responses to ecosystem change. 相似文献
125.
Parra A Oyarzún J Maturana H Kretschmer N Meza F Oyarzún R 《Environmental monitoring and assessment》2011,181(1-4):69-82
This contribution analyzes water chemical data for the Choapa basin, North Central Chile, for the period 1980-2004. The parameters considered are As, Cu Fe, pH, EC, SO??2, Cl?1, and HCO[Formula: see text], from samples taken in nine monitoring stations throughout the basin. Results show rather moderate contents of As, Cu, and Fe, with the exception of the Cuncumén River and the Aucó creek, explained by the influence of the huge porphyry copper deposit of Los Pelambres and by the presence of mining operations, respectively. When compared against results obtained in previous researches at the neighboring Elqui river basin, which host the El Indio Au-Cu-As district, a much reduced grade of pollution is recognized for the Choapa basin. Considering the effect of acid rock drainage (ARD)-related Cu contents on the fine fraction of the sediments of both river basins, the differences recorded are even more striking. Although the Los Pelambres porphyry copper deposit, on the headwaters of the Choapa river basin, is between one and two orders of magnitude bigger than El Indio, stream water and sediments of the former exhibit significantly lower copper contents than those of the latter. A main factor which may explain these results is the smaller degree of H(?+?)-metasomatism on the host rocks of the Los Pelambres deposit, where mafic andesitic volcanic rocks presenting propylitic hydrothermal alteration are dominant. This fact contrast with the highly altered host rocks of El Indio district, where most of them have lost their potential to neutralize ARD. 相似文献
126.
Susan A. Weiner David A. Galbraith Dean C. Adams Nicole Valenzuela Fernando B. Noll Christina M. Grozinger Amy L. Toth 《Die Naturwissenschaften》2013,100(8):795-799
DNA methylation plays an important role in the epigenetic control of developmental and behavioral plasticity, with connections to the generation of striking phenotypic differences between castes (larger, reproductive queens and smaller, non-reproductive workers) in honeybees and ants. Here, we provide the first comparative investigation of caste- and life stage-associated DNA methylation in several species of bees and vespid wasps displaying different levels of social organization. Our results reveal moderate levels of DNA methylation in most bees and wasps, with no clear relationship to the level of sociality. Strikingly, primitively social Polistes dominula paper wasps show unusually high overall DNA methylation and caste-related differences in site-specific methylation. These results suggest DNA methylation may play a role in the regulation of behavioral and physiological differences in primitively social species with more flexible caste differences. 相似文献
127.
128.
Tim W. Clark Nicole Mazur † Robert J. Begg ‡ and Steven J. Cork§ 《Conservation biology》2000,14(3):691-701
Abstract: Adequacy of the ongoing koala policy process and whether it can conserve koalas is currently in dispute. To address this issue, interdisciplinary guidelines are available to improve koala policy and management and to find consensus. These guidelines focus attention on five policy elements. The first three are rational, political, and moral perspectives on koala policy; the fourth the standpoint of a participant, and the fifth is knowledge integration for practical action. We discuss and illustrate these elements with koala case material. Rationality in policy is addressed through problem orientation, which requires participants to clarify goals, identify problems, and create alternatives in an iterative way. We examined the political dynamics—value clashes—in decision processes. A decision process ideally clarifies and secures common interests. We provide standards for each decision function, such as reliability, comprehensiveness, timeliness. Morality rests on basic premises that are used to justify policy positions. Clarification of the participant's standpoint addresses differing personalities, epistemologies, disciplines, and organizational and parochial biases. Integrating knowledge for practical policy action requires a conceptual framework that is up to the demands of the task. Together the five policy elements make up a logically comprehensive set of interrelated concepts for koala policy development, implementation, and appraisal. Many opportunities exist to use these guidelines skillfully in on-the-ground koala conservation efforts to improve koala policy outcomes. 相似文献
129.
130.