Biotic Impoverishment and Homogenization in Unfragmented Forest Understory Communities

Abstract:  Ecological change is often hard to document because of a lack of reliable baseline data. Several recent then-versus-now surveys of temperate forest and grassland communities demonstrate losses of local plant species, but most are based on data from a single site. We resurveyed understory communities in 62 upland forest stands in northern Wisconsin (U.S.A.) for which quantitative baseline data exist from 50 years ago. These stands are within a largely unfragmented region but vary in species composition and successional stage. We collected data on changes in (1) total and native species richness, (2) the ratio of exotic to native species, (3) the relative abundance of habitat generalists, and (4) community similarity among sites. We also compared how these rates of change varied over time. Over the past 50 years, native species density declined an average of 18.5% at the 20-m² scale, whereas the ratio of exotic species to native species increased at 80% of all sites. Habitat generalists increased, and habitat specialists declined, accounting in part for an 8.7% rise in average similarity in species composition among sites. Most of these changes cannot be related to succession, habitat loss, or invasion by exotic species. Areas without deer hunting showed the greatest declines in native species density, with parks and research natural areas faring no better than unprotected stands. Animal-pollinated and animal-dispersed species also declined, particularly at unhunted sites. These results demonstrate the power of quantitative multistand data for assessing ecological change and identify overabundant deer as a key driver of community change. Because maintaining forest habitats alone fails to preserve plant diversity at local scales, local biotic simplification seems likely to continue in the region unless active efforts are taken to protect diversity.     

Viability Analysis of Reef Fish Populations Based on Limited Demographic Information

Abstract:  Marine protected areas (MPAs) that allow some degree of artisanal fishing have been proposed to control the overexploitation of marine resources while allowing extraction by local communities. Nevertheless, the management of MPAs is often impaired by the absence of data on the status of their resources. We devised a method to estimate population growth rates with the type of data that are usually available for reef fishes. We used 7 years of spatially explicit abundance data on the leopard grouper ( Mycteroperca rosacea ) in an MPA in the Gulf of California, Mexico, to construct a matrix population model that incorporated the effects of El Niño/La Niña Southern Oscillation on population dynamics. An environmental model that estimated different demographic estimates for El Niño and La Niña periods performed better than a single-environment model, and a single-habitat model performed better than a model that considered different depths as different habitats. Our results suggest that the population of the leopard grouper off the main island of the MPA is not viable under present conditions. Although the impact of fishing on leopard grouper populations in the MPA has not yet been established, fishing should be closed as a precautionary measure at this island if a priority of the MPA is to ensure the sustainability of its fish populations.     

Lag Effects in the Impacts of Mass Coral Bleaching on Coral Reef Fish, Fisheries, and Ecosystems

Abstract:  Recent episodes of coral bleaching have led to wide-scale loss of reef corals and raised concerns over the effectiveness of existing conservation and management efforts. The 1998 bleaching event was most severe in the western Indian Ocean, where coral declined by up to 90% in some locations. Using fisheries-independent data, we assessed the long-term impacts of this event on fishery target species in the Seychelles, the overall size structure of the fish assemblage, and the effectiveness of two marine protected areas (MPAs) in protecting fish communities. The biomass of fished species above the size retained in fish traps changed little between 1994 and 2005, indicating no current effect on fishery yields. Biomass remained higher in MPAs, indicating they were effective in protecting fish stocks. Nevertheless, the size structure of the fish communities, as described with size-spectra analysis, changed in both fished areas and MPAs, with a decline in smaller fish (<30 cm) and an increase in larger fish (>45 cm). We believe this represents a time-lag response to a reduction in reef structural complexity brought about because fishes are being lost through natural mortality and fishing, and are not being replaced by juveniles. This effect is expected to be greater in terms of fisheries productivity and, because congruent patterns are observed for herbivores, suggests that MPAs do not offer coral reefs long-term resilience to bleaching events. Corallivores and planktivores declined strikingly in abundance, particularly in MPAs, and this decline was associated with a similar pattern of decline in their preferred corals. We suggest that climate-mediated disturbances, such as coral bleaching, be at the fore of conservation planning for coral reefs.     

Collaborating to Conserve Large Mammals in Southeast Asia

Abstract:  Depressed mammal densities characterize the interior of many Southeast Asian protected areas, and are the result of commercial and subsistence hunting. Local people are part of this problem but can participate in solutions through improved partnerships that incorporate local knowledge into problem diagnosis. The process of involving local people helps build a constituency that is more aware of its role (positive and negative) in a protected area and generates site-specific conservation assessments for management planning. We illustrate the practical details of initiating such a partnership through our work in a Thai wildlife sanctuary. Many protected areas in Southeast Asia present similar opportunities. In local workshops, village woodsmen were led through ranking exercises to develop a spatially explicit picture of 20-year trends in the abundance of 31 mammal species and to compare species-specific causes for declines. Within five taxonomic groups, leaf monkeys (primates), porcupines (rodents), tigers (large carnivores), civets (small carnivores), and elephants (ungulates) had declined most severely (37–74%). Commercial hunting contributed heavily to extensive population declines for most species, and subsistence hunting was locally significant for some small carnivores, leaf monkeys, and deer. Workshops thus clarified which species were at highest risk of local extinction, where the most threatened populations were, and causes for these patterns. Most important, they advanced a shared problem definition, thereby unlocking opportunities for collaboration. As a result, local people and sanctuary managers have increased communication, initiated joint monitoring and patrolling, and established wildlife recovery zones. Using local knowledge has limitations, but the process of engaging local people promotes collaborative action that large mammals in Southeast Asia need.     

Nature reserve construction and its contribution to the biodiversity conservation in China mainland

ＮａｔｕｒｅｒｅｓｅｒｖｅｃｏｎｓｔｒｕｃｔｉｏｎａｎｄｉｔｓｃｏｎｔｒｉｂｕｔｉｏｎｔｏｔｈｅｂｉｏｄｉｖｅｒｓｉｔｙｃｏｎｓｅｒｖａｔｉｏｎｉｎＣｈｉｎａｍａｉｎｌａｎｄ￥ＪｉａｎｇＭｉｎｇｋａｎｇ；ＸｕｅＤａｙｕａｎ（ＮａｎｊｉｎｇＩｎｓｔｉｔ...     

Road accident fatality risks for “vulnerable” versus “protected” road users in northern Ghana

Background: Road traffic injuries (RTIs) are a serious epidemic that claims more than a million lives across the globe each year. The burden of RTIs is particularly pronounced in Africa and other low- and middle-income countries. The unfavorable disparity of the burden of road trauma in the world is largely attributable to unsafe vehicles, lack of appropriate road infrastructure, and the predominance of vulnerable road users (VRUs) in developing countries. However, little research exists in northern Ghana to highlight the scale and risk of death among road users.

Objective: The objective of this research was to establish the relative risk of death among road users in northern Ghana.

Methods: Crash data from police reports between 2007 and 2011 were analyzed for the Upper Regions of Ghana. Conditional probabilities and multivariable logistic regression techniques were used to report proportions and adjusted odds ratios (AORs), respectively.

Results: Generally, crashes in northern Ghana were extremely severe; that is, 35% of all injury related collisions were fatal. The proportion of fatal casualties ranged between 21% among victims of sideswipe collisions and 41% among pedestrians and victims of rear-end collisions. Though males were 6 times more likely to die than females overall, females were more likely to die as pedestrians (90% of all female casualty deaths) and males were more likely to die as riders/drivers (78% of all male casualty deaths). Pedestrians were 3 times more likely to die (odds ratio [OR] = 3.1; 95% confidence interval [CI], 2.4 to 4.1) compared with drivers/riders. Compared with drivers, the odds of death among cyclists was about 4 times higher (AOR = 3.6; 95% CI, 2.3 to 5.6) and about 2 times higher among motorcyclists (AOR = 1.6; 95% CI, 1.2 to 2.2). Compared with casualties aged between 30 and 59 years, children under 10 years and those aged 60 years and above were independently 2 times more likely to die in traffic collisions.

Conclusion: Provision of requisite road infrastructure is vital for the safety of VRUs in northern Ghana. Cycle paths and lanes (for cyclists) as well as sidewalks (for pedestrians) in particular will separate VRUs from motorists and improve their safety. Enforcement of traffic laws particularly regarding helmet use, speeding, and alcohol use will be beneficial. Introduction of the demerit points system in the enforcement of traffic regulations may have significant deterrent effects on road users who have the penchant for violating traffic regulations. Road safety education is also required to create responsible road users.     

国家公园建设背景下的公益型保护地研究进展

当前我国自然保护地体系改革正处于关键时期,公益型保护地是一种利用社会公益力量,由政府监督、民间管理并协调保护与发展的新型保护地模式。该模式注重社会公益力量在自然保护地建设中的作用,能够补充已有保护地资金、技术和人力的不足,填补了我国目前保护地体系的空缺。本文论述了国家公园建设背景下的公益保护地的内涵,分析了当前公益保护地的特征,讨论了国内外公益型保护地的运营管理机制,包括土地权利的获得、基于协议保护机制的保护地运营、特许经营在保护地的实施和社区保护模式的成功经验。今后我国公益型保护地的建设应鼓励公益组织与民间力量参与,在管理理念上应坚持保护第一和公益性,促进管理体制转变和科学划定界限,并完善公益组织参与保护地建设的激励和监督机制。     

沙区沙化土地封禁保护补偿标准的估算——最小数据方法在甘肃省民勤县的运用

论文以甘肃省民勤县沙化土地封禁保护实践工作为研究背景,运用最小数据方法,估算了激励沙区农户将沙化耕地自愿转化为封禁土地的生态补偿（封禁补偿）标准。以水资源服务表征土地管理方式转变之后的生态系统服务产出,由调查获得的农户机会成本推导出了水资源服务供给曲线,并计算出了封禁补偿标准与土地转化比例、水资源服务供给量之间的定量关系。研究结果表明：1）实施封禁补偿,可激励农户改变沙化耕地利用方式,减少农业用水需求量,增加生态用水供给量,对民勤和石羊河流域生态保护意义重大;2）民勤县规划封禁保护区总面积为1.55万hm²,期望水资源服务产出为1.02亿m³,需要按照19 770元·hm^-2的标准补偿才能激励农户实现这一政策目标;3）以新一轮退耕还林补偿标准3 600元·hm^-2为参照线,只能促使3.51%的沙化耕地转化为封禁土地,在设计封禁补偿机制时,需要提高封禁补偿标准。