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1.
Establishing nature reserves protects species from land cover conversion and the resulting loss of habitat. Even within a reserve, however, many factors such as fires and defoliating insects still threaten habitat and the survival of species. To address the risk to species survival after reserve establishment, reserve networks can be created that allow some redundancy of species coverage to maximize the expected number of species that survive in the presence of threats. In some regions, however, the threats to species within a reserve may be spatially correlated. As examples, fires, diseases, and pest infestations can spread from a starting point and threaten neighboring parcels’ habitats, in addition to damage caused at the initial location. This paper develops a reserve site selection optimization framework that compares the optimal reserve networks in cases where risks do and do not reflect spatial correlation. By exploring the impact of spatially-correlated risk on reserve networks on a stylized landscape and on an Oregon landscape, this analysis demonstrates an appropriate and feasible method for incorporating such post-reserve establishment risks in the reserve site selection literature as an additional tool to be further developed for future conservation planning. 相似文献
2.
Habitat destruction is driving biodiversity loss in remaining ecosystems, and ecosystem functioning and services often directly depend on biodiversity. Thus, biodiversity loss is likely creating an ecosystem service debt: a gradual loss of biodiversity‐dependent benefits that people obtain from remaining fragments of natural ecosystems. Here, we develop an approach for quantifying ecosystem service debts, and illustrate its use to estimate how one anthropogenic driver, habitat destruction, could indirectly diminish one ecosystem service, carbon storage, by creating an extinction debt. We estimate that c. 2–21 Pg C could be gradually emitted globally in remaining ecosystem fragments because of plant species loss caused by nearby habitat destruction. The wide range for this estimate reflects substantial uncertainties in how many plant species will be lost, how much species loss will impact ecosystem functioning and whether plant species loss will decrease soil carbon. Our exploratory analysis suggests that biodiversity‐dependent ecosystem service debts can be globally substantial, even when locally small, if they occur diffusely across vast areas of remaining ecosystems. There is substantial value in conserving not only the quantity (area), but also the quality (biodiversity) of natural ecosystems for the sustainable provision of ecosystem services. 相似文献
3.
In many economies, wealth is strikingly concentrated. Entrepreneurs--individuals with ownership in for-profit enterprises--comprise a large portion of the wealthiest individuals, and their behavior may help explain patterns in the national distribution of wealth. Entrepreneurs are less diversified and more heavily invested in their own companies than is commonly assumed in economic models. We present an intentionally simplified individual-based model of wealth generation among entrepreneurs to assess the role of chance and determinism in the distribution of wealth. We demonstrate that chance alone, combined with the deterministic effects of compounding returns, can lead to unlimited concentration of wealth, such that the percentage of all wealth owned by a few entrepreneurs eventually approaches 100%. Specifically, concentration of wealth results when the rate of return on investment varies by entrepreneur and by time. This result is robust to inclusion of realities such as differing skill among entrepreneurs. The most likely overall growth rate of the economy decreases as businesses become less diverse, suggesting that high concentrations of wealth may adversely affect a country's economic growth. We show that a tax on large inherited fortunes, applied to a small portion of the most fortunate in the population, can efficiently arrest the concentration of wealth at intermediate levels. 相似文献
4.
Integrating economic costs into conservation planning 总被引:3,自引:0,他引:3
Naidoo R Balmford A Ferraro PJ Polasky S Ricketts TH Rouget M 《Trends in ecology & evolution》2006,21(12):681-687
Recent studies that incorporate the spatial distributions of biological benefits and economic costs in conservation planning have shown that limited budgets can achieve substantially larger biological gains than when planning ignores costs. Despite concern from donors about the effectiveness of conservation interventions, these increases in efficiency from incorporating costs into planning have not yet been widely recognized. Here, we focus on what these costs are, why they are important to consider, how they can be quantified and the benefits of their inclusion in priority setting. The most recent work in the field has examined the degree to which dynamics and threat affect the outcomes of conservation planning. We assess how costs fit into this new framework and consider prospects for integrating them into conservation planning. 相似文献
5.
John C. Withey Joshua J. Lawler Stephen Polasky Andrew J. Plantinga Erik J. Nelson Peter Kareiva Chad B. Wilsey Carrie A. Schloss Theresa M. Nogeire Aaron Ruesch Jorge Ramos Jr Walter Reid 《Ecology letters》2012,15(11):1249-1256
Efficient conservation planning requires knowledge about conservation targets, threats to those targets, costs of conservation and the marginal return to additional conservation efforts. Systematic conservation planning typically only takes a small piece of this complex puzzle into account. Here, we use a return‐on‐investment (ROI) approach to prioritise lands for conservation at the county level in the conterminous USA. Our approach accounts for species richness, county area, the proportion of species' ranges already protected, the threat of land conversion and land costs. Areas selected by a complementarity‐based greedy heuristic using our full ROI approach provided greater averted species losses per dollar spent compared with areas selected by heuristics accounting for richness alone or richness and cost, and avoided acquiring lands not threatened with conversion. In contrast to traditional prioritisation approaches, our results highlight conservation bargains, opportunities to avert the threat of development and places where conservation efforts are currently lacking. 相似文献
6.
Fengchao Yu Sarah E. Haynes Guo Ci Teo Dmitry M. Avtonomov Daniel A. Polasky Alexey I. Nesvizhskii 《Molecular & cellular proteomics : MCP》2020,19(9):1575-1585
Highlights
- •MSFragger now supports raw timsTOF PASEF data.
- •IonQuant performs fast and accurate feature detection and quantification.
- •MSFragger and IonQuant provide excellent performance for timsTOF PASEF data.
- •Flexibility allows for complex analyses, such as semi-enzymatic and open search.
7.
Kent Kovacs Stephen Polasky Erik Nelson Bonnie L. Keeler Derric Pennington Andrew J. Plantinga Steven J. Taff 《PloS one》2013,8(6)
We evaluate the return on investment (ROI) from public land conservation in the state of Minnesota, USA. We use a spatially-explicit modeling tool, the Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST), to estimate how changes in land use and land cover (LULC), including public land acquisitions for conservation, influence the joint provision and value of multiple ecosystem services. We calculate the ROI of a public conservation acquisition as the ratio of the present value of ecosystem services generated by the conservation to the cost of the conservation. For the land scenarios analyzed, carbon sequestration services generated the greatest benefits followed by water quality improvements and recreation opportunities. We found ROI values ranged from 0.21 to 5.28 depending on assumptions about future land use change, service values, and discount rate. Our study suggests conservation is a good investment as long as investments are targeted to areas with low land costs and high service values. 相似文献
8.
C. Packer A. Loveridge S. Canney T. Caro S.T. Garnett M. Pfeifer K.K. Zander A. Swanson D. MacNulty G. Balme H. Bauer C.M. Begg K.S. Begg S. Bhalla C. Bissett T. Bodasing H. Brink A. Burger A.C. Burton B. Clegg S. Dell A. Delsink T. Dickerson S.M. Dloniak D. Druce L. Frank P. Funston N. Gichohi R. Groom C. Hanekom B. Heath L. Hunter H.H. DeIongh C.J. Joubert S.M. Kasiki B. Kissui W. Knocker B. Leathem P.A. Lindsey S.D. Maclennan J.W. McNutt S.M. Miller S. Naylor P. Nel C. Ng'weno K. Nicholls J.O. Ogutu E. Okot‐Omoya B.D. Patterson A. Plumptre J. Salerno K. Skinner R. Slotow E.A. Sogbohossou K.J. Stratford C. Winterbach H. Winterbach S. Polasky 《Ecology letters》2013,16(5):635-641
Conservationists often advocate for landscape approaches to wildlife management while others argue for physical separation between protected species and human communities, but direct empirical comparisons of these alternatives are scarce. We relate African lion population densities and population trends to contrasting management practices across 42 sites in 11 countries. Lion populations in fenced reserves are significantly closer to their estimated carrying capacities than unfenced populations. Whereas fenced reserves can maintain lions at 80% of their potential densities on annual management budgets of $500 km−2, unfenced populations require budgets in excess of $2000 km−2 to attain half their potential densities. Lions in fenced reserves are primarily limited by density dependence, but lions in unfenced reserves are highly sensitive to human population densities in surrounding communities, and unfenced populations are frequently subjected to density‐independent factors. Nearly half the unfenced lion populations may decline to near extinction over the next 20–40 years. 相似文献
9.
Daniel A. Polasky Daniel J. Geiszler Fengchao Yu Alexey I. Nesvizhskii 《Molecular & cellular proteomics : MCP》2022,21(3):100205
Rapidly improving methods for glycoproteomics have enabled increasingly large-scale analyses of complex glycopeptide samples, but annotating the resulting mass spectrometry data with high confidence remains a major bottleneck. We recently introduced a fast and sensitive glycoproteomics search method in our MSFragger search engine, which reports glycopeptides as a combination of a peptide sequence and the mass of the attached glycan. In samples with complex glycosylation patterns, converting this mass to a specific glycan composition is not straightforward; however, as many glycans have similar or identical masses. Here, we have developed a new method for determining the glycan composition of N-linked glycopeptides fragmented by collisional or hybrid activation that uses multiple sources of information from the spectrum, including observed glycan B-type (oxonium) and Y-type ions and mass and precursor monoisotopic selection errors to discriminate between possible glycan candidates. Combined with false discovery rate estimation for the glycan assignment, we show that this method is capable of specifically and sensitively identifying glycans in complex glycopeptide analyses and effectively controls the rate of false glycan assignments. The new method has been incorporated into the PTM-Shepherd modification analysis tool to work directly with the MSFragger glyco search in the FragPipe graphical user interface, providing a complete computational pipeline for annotation of N-glycopeptide spectra with false discovery rate control of both peptide and glycan components that is both sensitive and robust against false identifications. 相似文献
10.
Projecting global land-use change and its effect on ecosystem service provision and biodiversity with simple models 总被引:5,自引:0,他引:5
Nelson E Sander H Hawthorne P Conte M Ennaanay D Wolny S Manson S Polasky S 《PloS one》2010,5(12):e14327