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71.
Widespread human action and behavior change is needed to achieve many conservation goals. Doing so at the requisite scale and pace will require the efficient delivery of outreach campaigns. Conservation gains will be greatest when efforts are directed toward places of high conservation value (or need) and tailored to critical actors. Recent strategic conservation planning has relied primarily on spatial assessments of biophysical attributes, largely ignoring the human dimensions. Elsewhere, marketers, political campaigns, and others use microtargeting—predictive analytics of big data—to identify people most likely to respond positively to particular messages or interventions. Conservationists have not yet widely capitalized on these techniques. To investigate the effectiveness of microtargeting to improve conservation, we developed a propensity model to predict restoration behavior among 203,645 private landowners in a 5,200,000 ha study area in the Chesapeake Bay Watershed (U.S.A.). To isolate the additional value microtargeting may offer beyond geospatial prioritization, we analyzed a new high-resolution land-cover data set and cadastral data to identify private owners of riparian areas needing restoration. Subsequently, we developed and evaluated a restoration propensity model based on a database of landowners who had conducted restoration in the past and those who had not (n = 4978). Model validation in a parallel database (n = 4989) showed owners with the highest scorers for propensity to conduct restoration (i.e., top decile) were over twice as likely as average landowners to have conducted restoration (135%). These results demonstrate that microtargeting techniques can dramatically increase the efficiency and efficacy of conservation programs, above and beyond the advances offered by biophysical prioritizations alone, as well as facilitate more robust research of many social–ecological systems.  相似文献   
72.
Based on a case study of the Stadshaven port redevelopment in Rotterdam, this paper explores whether existing spatial planning mechanisms and processes can be used to facilitate local-level investment in climate-resilient public infrastructure and/or whether new processes and mechanisms are required to encourage investment in climate adaptation. The study reveals several key findings. First, a lack of conventional funding sources or formalised regulatory framework allowed room for experimentation with existing mechanisms and flexible strategies. Second, project planners are currently ambivalent towards introducing new mechanisms as a means to overcome implementation challenges. The case provides evidence about the role of the governance process, not simply as a means of system coordination that exists in isolation from institutional norms and values, but rather as a space for innovation, which can contribute towards reducing the financial gap associated with climate adaptation.  相似文献   
73.
Finding sustainable ways to increase the amount of private land protected for biodiversity is challenging for many conservation organizations. In some countries, organizations use revolving‐fund programs, whereby land is purchased and then sold to conservation‐minded owners under condition they enter into a conservation covenant or easement. The sale proceeds are used to purchase, protect, and sell additional properties, incrementally increasing the amount of protected private land. Because the effectiveness of this approach relies on selecting appropriate properties, we explored factors currently considered by practitioners and how these are integrated into decision making. We conducted exploratory, semistructured interviews with managers from each of the 5 major revolving funds in Australia. Responses indicated although conservation factors are important, financial and social factors are also highly influential. A major determinant was whether the property could be resold within a reasonable period at a price that replenishes the fund. To facilitate resale, often selected properties include the potential for the construction of a dwelling. Practitioners face with clear trade‐offs between conservation, financial, amenity, and other factors in selecting properties and 3 main challenges: recovering the costs of acquisition, protection, and resale; reselling the property; and meeting conservation goals. Our findings suggest the complexity of these decisions may constrain revolving‐fund effectiveness. Drawing from participant responses, we identified potential strategies to mitigate these risks, such as providing adequate recreational space without jeopardizing ecological assets. We suggest managers could benefit from a shared‐learning and adaptive approach to property selection given the commonalities between programs. Understanding how practitioners deal with complex decisions in the implementation of revolving funds helps identify future research to improve the performance of this conservation tool.  相似文献   
74.
Effective conservation policies require comprehensive knowledge of biodiversity. However, knowledge shortfalls still remain, hindering possibilities to improve decision making and built such policies. During the last 2 decades, conservationists have made great efforts to allocate resources as efficiently as possible but have rarely considered the idea that if research investments are also strategically allocated, it would likely fill knowledge gaps while simultaneously improving conservation actions. Therefore, prioritizing areas where both conservation and research actions could be conducted becomes a critical endeavor that can further maximize return on investment. We used Zonation, a conservation planning tool and geographical distributions of amphibians, birds, mammals, and reptiles to suggest and compare priority areas for conservation and research of terrestrial vertebrates worldwide. We also evaluated the degree of human disturbance in both types of priority areas by describing the value of the human footprint index within such areas. The spatial concordance between priority conservation and research areas was low: 0.36% of the world's land area. In these areas, we found it would be possible to protect almost half of the currently threatened species and to gather information on nearly 42% of data-deficient (DD) species. We also found that 6199 protected areas worldwide are located in such places, although only 35% of them have strict conservation purposes. Areas of consensus between conservation and research areas represent an opportunity for simultaneously conserving and acquiring knowledge of threatened and DD species of vertebrates. Although the picture is not the most encouraging, joint conservation and research efforts are possible and should be fostered to save vertebrate species from our own ignorance and extinction.  相似文献   
75.
Calf suckling behaviour is a valid measure of maternal investment in the Saharan arrui, Ammotragus lervia sahariensis, since this variable is strongly correlated with the inter-birth interval. High-ranking females allocate their resources preferentially towards their sons, as the average suckling rate is significantly higher in male calves than in female calves during their 1st month of life, when maternal investment reaches the highest values of the whole lactation period. However, average suckling-bout duration shows no sex differences. Some maternal behaviours, such as sniffing and licking, are strongly correlated with suckling events. Only during the calves’ 1st week is the mother responsible for maintaining proximity; but from the following week on the calves are mainly responsible for maintaining it. In addition, when the calves are 1 month old, high-ranking females tend to maintain a stronger link with their male calves. Female calves spend more time with their mothers than male calves during their 1st month of life, if the mother’s rank is lower than 60%; otherwise, the opposite occurs, male calves being close to their mothers for longer, even from their 1st week of life. Finally, the higher the maternal rank the higher the proportion of male calves delivered. Received: 18 April 1995/Accepted after revision: 11 February 1996  相似文献   
76.
In Lepidoptera polyandry is common and females may increase their lifetime reproductive output through repeated matings if they acquire essential resources from male ejaculates. However, the paternity of males mating with previously-mated females is far from assured unless sperm precedence is absolute. In this study on the polyandrous armyworm, Pseudaletia unipuncta, we used two strains of male (the black-eyed wild type and a red-eyed homozygous, recessive mutant), mated with red-eyed females, to determine (i) whether male investment has any impact on female reproductive output, and (ii) if females do benefit from multiple matings, to what extent males fertilize the eggs to which they contributed. Multiple mating resulted in a significant increase in both the fecundity and longevity of females. However, the degree of sperm precedence (those eggs fertilized by the second male) varied from 0–100%, but was not affected by either male size or age, or by the duration of copulation. In cases where sperm precedence was <50% (x = 12%) females produced significantly more eggs (1384 versus 940) prior to the second mating than females where sperm precedence was >50% (x = 89%), indicating that the quality of the first mating influenced the fertilization success of the female's second mate.  相似文献   
77.
Body size has often been related to reproductive success in bees and wasps. The objective of this 3-year study was to analyze the relationship between nesting female body size, provisioning rate and longevity and their effect on several traits related to parental investment and reproductive success in the solitary bee Osmia cornuta. Body size was not correlated to longevity, and it was only correlated to provisioning rate in the third year (with poor weather conditions during nesting). Variation in fecundity, offspring size and offspring mortality was not well explained by nesting female body size in any of the 3 years. However, in the third year, small females biased their investment toward males, the sex requiring smaller pollen–nectar provisions. Large females were more successful usurpers of other females' nests, but fecundity of usurpers was no higher than fecundity of nonusurpers. Large females were more likely to establish at the release site, probably in relation to size-dependent vigor at emergence. A review of the literature on parental investment in solitary aculeate Hymenoptera showed a stronger relationship between body size and reproductive success in wasps than in bees. In O. cornuta, fecundity was strongly related to longevity and provisioning rate in all 3 years. Offspring size was associated with provisioning rate in 1 year, when females with higher provisioning rates tended to produce larger sons and daughters. Both longevity and provisioning rate appeared to be strongly conditioned by stochastic events.  相似文献   
78.
Allocation of parental investment is predicted to be equal at the population level between both sexes of offspring, and should lead to sex ratio biases in species that exhibit a sex-difference in parental care. Sex-differences in parental care are rarely quantified. We measured daily energy expenditure in free-living nestlings of the extremely sexually size dimorphic European sparrowhawk (Accipiter nisus), using the doubly labelled water method. These data were combined with measured growth characteristics to estimate daily and total metabolised energy intake of male and female young during the nestling stage. Females reached an asymptotic body mass 1.6 times higher than males. This resulted in a total metabolised energy an estimated 1.4 times higher for the nestling stage. Furthermore, we observed a decline in daily metabolised energy with an increase in brood size, which was significantly stronger for females than for males. These results are discussed in the context of Fishers equal allocation theory. Empirical evidence of a sex ratio bias at the end of parental care, with an overall excess of males, is lacking in this species. Consequently, our data do not support the idea of equal allocation between the sexes. The observed sex difference in daily metabolised energy in response to brood size may give scope for sex ratio bias at the level of the individual brood.  相似文献   
79.
从环境污染治理投资的相关因子和系数分析入手,对治理投资质量和效果分别建立了量化函数关系,由此计算结果与理论标准值比较,则可确定其投资质量与回报结果。  相似文献   
80.
Abstract:  Uncertainty in the implementation and outcomes of conservation actions that is not accounted for leaves conservation plans vulnerable to potential changes in future conditions. We used a decision-theoretic approach to investigate the effects of two types of investment uncertainty on the optimal allocation of global conservation resources for land acquisition in the Mediterranean Basin. We considered uncertainty about (1) whether investment will continue and (2) whether the acquired biodiversity assets are secure, which we termed transaction uncertainty and performance uncertainty, respectively. We also developed and tested the robustness of different rules of thumb for guiding the allocation of conservation resources when these sources of uncertainty exist. In the presence of uncertainty in future investment ability (transaction uncertainty), the optimal strategy was opportunistic, meaning the investment priority should be to act where uncertainty is highest while investment remains possible. When there was a probability that investments would fail (performance uncertainty), the optimal solution became a complex trade-off between the immediate biodiversity benefits of acting in a region and the perceived longevity of the investment. In general, regions were prioritized for investment when they had the greatest performance certainty, even if an alternative region was highly threatened or had higher biodiversity value. The improved performance of rules of thumb when accounting for uncertainty highlights the importance of explicitly incorporating sources of investment uncertainty and evaluating potential conservation investments in the context of their likely long-term success.  相似文献   
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