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81.
Caught between ongoing habitat destruction and funding shortfalls, conservation organizations are using systematic planning approaches to identify places that offer the highest biodiversity return per dollar invested. However, available tools do not account for the landscape of funding for conservation or quantify the constraints this landscape imposes on conservation outcomes. Using state‐level data on philanthropic giving to and investments in land conservation by a large nonprofit organization, we applied linear regression to evaluate whether the spatial distribution of conservation philanthropy better explained expenditures on conservation than maps of biodiversity priorities, which were derived from a planning process internal to the organization and return on investment (ROI) analyses based on data on species richness, land costs, and existing protected areas. Philanthropic fund raising accounted for considerably more spatial variation in conservation spending (r2 = 0.64) than either of the 2 systematic conservation planning approaches (r2 = 0.08–0.21). We used results of one of the ROI analyses to evaluate whether increases in flexibility to reallocate funding across space provides conservation gains. Small but plausible “tax” increments of 1–10% on states redistributed to the optimal funding allocation from the ROI analysis could result in gains in endemic species protected of 8.5–80.2%. When such increases in spatial flexibility are not possible, conservation organizations should seek to cultivate increased support for conservation in priority locations. We used lagged correlations of giving to and spending by the organization to evaluate whether investments in habitat protection stimulate future giving to conservation. The most common outcome at the state level was that conservation spending quarters correlated significantly and positively with lagged fund raising quarters. In effect, periods of high fund raising for biodiversity followed (rather than preceded) periods of high expenditure on land conservation projects, identifying one mechanism conservation organizations could explore to seed greater activity in priority locations. Our results demonstrate how limitations on the ability of conservation organizations to reallocate their funding across space can impede organizational effectiveness and elucidate ways conservation planning tools could be more useful if they quantified and incorporated these constraints.  相似文献   
82.
Many drivers of mangrove forest loss operate over large scales and are most effectively addressed by policy interventions. However, conflicting or unclear policy objectives exist at multiple tiers of government, resulting in contradictory management decisions. To address this, we considered four approaches that are being used increasingly or could be deployed in Southeast Asia to ensure sustainable livelihoods and biodiversity conservation. First, a stronger incorporation of mangroves into marine protected areas (that currently focus largely on reefs and fisheries) could resolve some policy conflicts and ensure that mangroves do not fall through a policy gap. Second, examples of community and government comanagement exist, but achieving comanagement at scale will be important in reconciling stakeholders and addressing conflicting policy objectives. Third, private‐sector initiatives could protect mangroves through existing and novel mechanisms in degraded areas and areas under future threat. Finally, payments for ecosystem services (PES) hold great promise for mangrove conservation, with carbon PES schemes (known as blue carbon) attracting attention. Although barriers remain to the implementation of PES, the potential to implement them at multiple scales exists. Closing the gap between mangrove conservation policies and action is crucial to the improved protection and management of this imperiled coastal ecosystem and to the livelihoods that depend on them.  相似文献   
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84.
Abstract: Spatial and temporal dynamics of ecological processes have long been considered important in marine systems, but seldom have conservation objectives been set for them. Climate change makes the consideration of the dynamics of ecological processes in the design of marine protected areas critical. We analyzed sea‐surface temperature (SST) trends and variability in Great Barrier Reef Marine Park (GBRMP) for 25 years and formulated and tested whether three sets of notional conservation objectives were met to illustrate the potential for planning to address climate change. Given mixed and limited evidence that no‐take areas increase resilience to disturbances such as anomalously high temperatures (i.e., temperatures ≥1 °C above weekly mean temperature), our conservation objectives focused on areas less likely to be affected by such events at extents ranging from the entire Great Barrier Reef to the system of no‐take zones and individual no‐take zones. The objective sets were (1) at least 50% of temperature refugia (i.e., pixels that had high‐temperature anomalies <5% or <7% of the time) within no‐take zones, (2) maximum occurrence of high‐temperature anomalies is <10%,< 20%, or <30% of total no‐take area 90% of the time, and (3) coverage of any single no‐take zone by high‐temperature anomalies occurs <5% or <10% of the time. We used satellite imagery from 1985–2009 to measure SST to determine high‐temperature anomalies. SSTs in the Great Barrier Reef increased significantly in some regions, and some of the conservation objectives were met by the park's current zoning plan. Dialogue between conservation scientists and managers is needed to develop appropriate conservation objectives under climate change and strategies to meet them.  相似文献   
85.
Nylon bags containing yellow leaves of Rhizophora apiculata and Avicennia marina, were immersed for 80 days from August to October, 1996. the decomposing leaves were collected every 10 days and analysed for dry weight loss and six biochemical parameters: tannins, total amino acids, total sugars, total nitrogen, total lipids and fatty acid profile. the leaf weight initially decreased very rapidly by about 50% of the start in two species of mangroves within 10 days. Similar changes were observed with tannins, total amino acids and sugars. However, the concentration of nitrogen increased significantly with decomposition. There was no significant change in total lipid and fatty acid profile. the highest concentration of fatty acid in the decomposing leaves was palmitic acid (16:0). Unsaturated fatty acids such as, 18:1 w7c and 18:1 w9c were found to be present in decomposing leaves of both species.  相似文献   
86.
Abstract: Achieving multiple conservation objectives can be challenging, particularly under high uncertainty. Having agreed to limit seahorse (Hippocampus) exports to sustainable levels, signatories to the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) were offered the option of a single 10‐cm minimum size limit (MSL) as an interim management measure for all Hippocampus species (≥34). Although diverse stakeholders supported the recommended MSL, its biological and socioeconomic implications were not assessed quantitatively. We combined population viability analysis, model sensitivity analysis, and economic information to evaluate the trade‐off between conservation threat to and long‐term cumulative income from these exploited marine fishes of high conservation concern. We used the European long‐snouted seahorse (Hippocampus guttulatus) as a representative species to compare the performance of MSLs set at alternative biological reference points. Our sensitivity analyses showed that in most of our scenarios, setting the MSL just above size at maturity (9.7 cm in H. guttulatus) would not prevent exploited populations from becoming listed as vulnerable. By contrast, the relative risk of decline and extinction were almost halved—at a cost of only a 5.6% reduction in long‐term catches—by increasing the MSL to the size reached after at least one full reproductive season. On the basis of our analysis, a precautionary increase in the MSL could be compatible with sustaining fishers' livelihoods and international trade. Such management tactics that aid species conservation and have minimal effects on long term catch trends may help bolster the case for CITES trade management of other valuable marine fishes.  相似文献   
87.
Abstract: In many areas of the developing world, the establishment of permanent marine reserves is inhibited by cultural norms or socioeconomic pressures. Community conserved areas that are periodically harvested are increasingly being implemented as fisheries management tools, but few researchers have empirically compared them with permanently closed reserves. We used a hierarchal control‐impact experimental design to compare the abundance and biomass of reef fishes, invertebrates, and substrate composition in periodically harvested and permanent reserves and in openly fished (control sites) of the South Pacific island country of Vanuatu. Fished species had significantly higher biomass in periodically harvested reserves than in adjacent openly fished areas. We did not detect differences in substratum composition between permanent reserves and openly fished areas or between permanent reserves and periodically harvested reserves. Giant clams (tridacnids) and top shells (Trochus niloticus) were vulnerable to periodic harvest, and we suggest that for adequate management of these species, periodically harvested community conservation areas be used in conjunction with other management strategies. Periodic harvest within reserves is an example of adaptive and flexible management that may meet conservation goals and that is suited to the social, economic, and cultural contexts of many coastal communities in the developing world.  相似文献   
88.
人工污水对白骨壤生长的影响   总被引:12,自引:3,他引:12  
在模拟潮汐条件下以正常、5倍和10倍浓度的人工污水处理红树林植物白骨壤la生幼苗,测定植株的根长、根径、茎高、茎径、叶片数、生物量以及开花结果等指标。结果表明:正常浓度和5倍浓度组的上述指标显著高于对照组,10倍浓度组的这些指标大于或接近对照组;说明:一定浓度的污水可以促进白骨壤的生长和开花结果。  相似文献   
89.
江涛  冻文静  吴霓  江天久 《中国环境科学》2011,31(11):1864-1869
对海洋卡盾藻日本株(Chattonella marina Japan,CMJP)在不同盐度、营养盐条件及不同生长期的过氧化氢产生特点进行了研究.结果表明:H2O2浓度峰值出现在CMJP对数生长期(4~8d),以第6d达到最大,为0.97×10-4nmol/cell.在N:P为8:1和16:1的情况下,CMJP生长较快,藻细胞在对数生长末期之前一直保持较高密度.CMJP产生的H2O2量与藻类生长呈现出一定的相反趋势,在藻细胞适宜生长的N:P下,产生的H2O2浓度较小.在N:P为16:1时单个藻细胞的H2O2量最低(0.40×10-4nmol/cell),仅是N:P为32:1时(1.17 ×10-4nmol/cell)的1/3,N:P为8:1时,单个藻细胞的H2O2浓度为0.63 ×10-4nmol/cell. CMJP在盐度为20,25psu时生长较好且藻细胞达到较高密度,在盐度为10,15,30psu时藻密度较低,表明低盐和高盐条件均不利于CMJP的生长.盐度对CMJP过氧化氢的产量有一定的影响,在高盐度下单个藻细胞的H2O2产量增加,盐度为30psu时,H202浓度最高(1.1×10-4nmol/cell).  相似文献   
90.
The conservation implications of large‐scale rainforest clearing and fragmentation on the persistence of functional and taxonomic diversity remain poorly understood. If traits represent adaptive strategies of plant species to particular circumstances, the expectation is that the effect of forest clearing and fragmentation will be affected by species functional traits, particularly those related to dispersal. We used species occurrence data for woody plants in 46 rainforest patches across 75,000 ha largely cleared of forest by the early 1900s to determine the combined effects of area reduction, fragmentation, and patch size on the taxonomic structure and functional diversity of subtropical rainforest. We compiled species trait values for leaf area, seed dry mass, wood density, and maximum height and calculated species niche breadths. Taxonomic structure, trait values (means, ranges), and the functional diversity of assemblages of climbing and free‐standing plants in remnant patches were quantified. Larger rainforest patches had higher species richness. Species in smaller patches were taxonomically less related than species in larger patches. Free‐standing plants had a high percentage of frugivore dispersed seeds; climbers had a high proportion of small wind‐dispersed seeds. Connections between the patchy spatial distribution of free‐standing species, larger seed sizes, and dispersal syndrome were weak. Assemblages of free‐standing plants in patches showed more taxonomic and spatial structuring than climbing plants. Smaller isolated patches retained relatively high functional diversity and similar taxonomic structure to larger tracts of forest despite lower species richness. The response of woody plants to clearing and fragmentation of subtropical rainforest differed between climbers and slow‐growing mature‐phase forest trees but not between climbers and pioneer trees. Quantifying taxonomic structure and functional diversity provides an improved basis for conservation planning and management by elucidating the effects of forest‐area reduction and fragmentation. Efectos de la Forma de Crecimiento y Atributos Funcionales en la Respuesta de Plantas Leñosas al Desmonte y Fragmentación de Bosque Lluvioso Subtropical  相似文献   
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