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91.
Marleen van de Kerkhof Annemarie Groot Marien Borgstein Leontien Bos-Gorter 《Agriculture and Human Values》2010,27(3):307-319
Environmental pollution, animal diseases, and food scandals have marked the agricultural sector in the Netherlands and elsewhere
in the 1990s. The sector was high on the political and societal agenda and plans were developed to redesign the sector into
a more sustainable direction. Generally, monitoring of the agricultural sector is done by means of quantitative indicators
to measure social, ecological, and economic performance. To give more attention to the normative character of sustainable
development, the Dutch Ministry of Agriculture, Nature, and Food Quality requested for a participatory approach to evaluate
Dutch agriculture, which was characterized by stakeholder workshops, dialogue, and learning. This article describes and reflects
on this approach, using the Fourth Generation Evaluation framework developed by Guba and Lincoln (Fourth generation evaluation,
1989). Although there are several improvements to be made, the evaluation approach was successful in the way that it gave insight
into perceptions, visions, and ambitions of agricultural stakeholders with regard to sustainability. It also encouraged learning
about ways to make the agricultural sector more sustainable. And it contributed to the development of a monitoring approach
that is complementary to the quantitative, indicator-based, evaluation approach that is generally used and that can be used
every few years to see how perceptions and ambitions of stakeholders have developed. 相似文献
92.
93.
S.J. De Groot 《Aquaculture (Amsterdam, Netherlands)》1979,18(1):69-70
A simple mechanical feeding device is described which can volumetrically deliver a preset quantity of pelleted or granulated dry fish feed. 相似文献
94.
S.J. De Groot 《Aquaculture (Amsterdam, Netherlands)》1979,16(3):277
95.
96.
Flow variability structures freshwater fish community traits and life‐history patterns such as migration patterns between fresh and saltwater (diadromy). Few studies, however, have explored relationships between diadromy and flow regime while accounting for other abiotic covariables. The present paper used canonical ordinations to remove the shared variation between groups of explanatory variables that explain variation in fish communities and examine two objectives with New Zealand fishes: (i) to compare the unique contributions of Hydrological Regime, Climate, Habitat and Spatial‐Seasonal data sets to the variation of diadromous and nondiadromous fishes and (ii) to compare the relative contributions of a Hydrological Variability and Low‐Flow data set to community structure of both life‐history patterns. All explanatory variables explained a total of 20.15% and 29.58% of the variation in diadromous and nondiadromous fishes, respectively. Objective 1 analyses showed that the largest unique component of variation was explained by Hydrological Regime for nondiadromous fishes (12.17%), while Climate uniquely explained the most variation in diadromous fishes (4.3%), followed closely by Hydrological Regime (3.08%). Objective 2 analyses showed that Hydrological Variability uniquely explained five and 11 times more variation than the Low‐Flow data set in diadromous and nondiadromous fishes, respectively. Findings illustrate the importance of hydrological regime to New Zealand freshwater fishes. Specifically, aspects of hydrological variability uniquely account for more variation than aspects of low flow. Differing relative influences of hydrology between life‐history patterns suggest that diadromy may mediate the influence of flow regime. Results outline difficulties for environmental flow settings when biota display differing life histories. 相似文献
97.
Cann HM de Toma C Cazes L Legrand MF Morel V Piouffre L Bodmer J Bodmer WF Bonne-Tamir B Cambon-Thomsen A Chen Z Chu J Carcassi C Contu L Du R Excoffier L Ferrara GB Friedlaender JS Groot H Gurwitz D Jenkins T Herrera RJ Huang X Kidd J Kidd KK Langaney A Lin AA Mehdi SQ Parham P Piazza A Pistillo MP Qian Y Shu Q Xu J Zhu S Weber JL Greely HT Feldman MW Thomas G Dausset J Cavalli-Sforza LL 《Science (New York, N.Y.)》2002,296(5566):261-262
98.
S.J. De Groot 《Aquaculture (Amsterdam, Netherlands)》1978,13(1):86-87
99.
The potential interactions among governmental policies, investments andeconomic growth are complex and manifold. This paper will perform a systematic comparative analysis of the various economic insights that are currently available on these complex relationships, both theoretically (by a selective literature review) and empirically (by reviewing the empirically obtained insights). Despite the wide variety of potential theoretical relationshipsbetween government expenditures, taxation and growth, most empirical analyses are restricted to simple linear regressions of growth on some measure of government expenditures. We will indicate directions for future empirical research that may enrich our knowledge about the complex relationship between fiscal policies and economic growth, not only nationally but also regionally. 相似文献
100.