Temporal Analysis of Genetic Structure to Assess Population Dynamics of Reintroduced Swift Foxes

Reintroductions are increasingly used to reestablish species, but a paucity of long‐term postrelease monitoring has limited understanding of whether and when viable populations subsequently persist. We conducted temporal genetic analyses of reintroduced populations of swift foxes (Vulpes velox) in Canada (Alberta and Saskatchewan) and the United States (Montana). We used samples collected 4 years apart, 17 years from the initiation of the reintroduction, and 3 years after the conclusion of releases. To assess program success, we genotyped 304 hair samples, subsampled from the known range in 2000 and 2001, and 2005 and 2006, at 7 microsatellite loci. We compared diversity, effective population size, and genetic connectivity over time in each population. Diversity remained stable over time and there was evidence of increasing effective population size. We determined population structure in both periods after correcting for differences in sample sizes. The geographic distribution of these populations roughly corresponded with the original release locations, which suggests the release sites had residual effects on the population structure. However, given that both reintroduction sites had similar source populations, habitat fragmentation, due to cropland, may be associated with the population structure we found. Although our results indicate growing, stable populations, future connectivity analyses are warranted to ensure both populations are not subject to negative small‐population effects. Our results demonstrate the importance of multiple sampling years to fully capture population dynamics of reintroduced populations. Análisis Temporal de la Estructura Genética para Evaluar la Dinámica Poblacional de Zorros (Vulpes velox) Reintroducidos     

Mitigating the Effect of Development on Bats in England with Derogation Licensing

The Convention on Biological Diversity has catalyzed worldwide awareness of threats to biological diversity and stimulated global conservation strategies. These have led to national and international legislation and have generated debate about the most effective conservation actions. Under the EU Habitats Directive, all member states are obliged to establish a system for strict protection of species listed in Annex IV(a), which includes all bats. In England, this obligation has resulted in legislation that allows for derogation from strict protection under license, provided activities are undertaken to mitigate any potential negative effects on bat numbers. We used an evidence‐based approach to assess the cost‐effectiveness of mitigation strategies and the English bat‐derogation licensing process as a whole. We analyzed data from 389 bat derogation licenses issued in England from 2003 to 2005 relating to 1776 roosts and 15 species to determine the nature and extent of development and mitigation activities and their effects on bats. Overall the effects of licensed activities on roosts were negative. Despite the level of protection afforded to bats, the majority (68%) of roosts for which derogation licenses were issued were destroyed. There were species‐specific differences in the probability of roosts being destroyed, and impacts on roosts did not reflect a species’ conservation status. Information provided by licensees was inadequate and inconsistent. Most licensees (67%) failed to submit postdevelopment reports, and postdevelopment monitoring was conducted at only 19% of sites. Despite a minimum of £4.13 million spent on mitigation structures for bats from 2003 to 2005, it was unclear whether the licensing process meets EU obligations. On the basis of our results, we believe there is a need to overhaul the licensing process, to establish a comprehensive, standardized postdevelopment monitoring system, and to demonstrate that mitigation is commensurate with Britain's legal obligations. Mitigando el Efecto del Desarrollo sobre los Murciélagos en Inglaterra con Licencias de Derogación     

Fire Mosaics and Reptile Conservation in a Fire‐Prone Region

Fire influences the distribution of fauna in terrestrial biomes throughout the world. Use of fire to achieve a mosaic of vegetation in different stages of succession after burning (i.e., patch‐mosaic burning) is a dominant conservation practice in many regions. Despite this, knowledge of how the spatial attributes of vegetation mosaics created by fire affect fauna is extremely scarce, and it is unclear what kind of mosaic land managers should aim to achieve. We selected 28 landscapes (each 12.6 km²) that varied in the spatial extent and diversity of vegetation succession after fire in a 104,000 km² area in the semiarid region of southeastern Australia. We surveyed for reptiles at 280 sites nested within the 28 landscapes. The landscape‐level occurrence of 9 of the 22 species modeled was associated with the spatial extent of vegetation age classes created by fire. Biogeographic context and the extent of a vegetation type influenced 7 and 4 species, respectively. No species were associated with the diversity of vegetation ages within a landscape. Negative relations between reptile occurrence and both extent of recently burned vegetation (≤10 years postfire, n = 6) and long unburned vegetation (>35 years postfire, n = 4) suggested that a coarse‐grained mosaic of areas (e.g. >1000 ha) of midsuccessional vegetation (11–35 years postfire) may support the fire‐sensitive reptile species we modeled. This age class coincides with a peak in spinifex cover, a keystone structure for reptiles in semiarid and arid Australia. Maintaining over the long term a coarse‐grained mosaic of large areas of midsuccessional vegetation in mallee ecosystems will need to be balanced against the short‐term negative effects of large fires on many reptile species and a documented preference by species from other taxonomic groups, particularly birds, for older vegetation. Mosaicos de Fuego y la Conservación de Reptiles en una Región Propensa al Fuego     

Paradigms for parasite conservation

Parasitic species, which depend directly on host species for their survival, represent a major regulatory force in ecosystems and a significant component of Earth's biodiversity. Yet the negative impacts of parasites observed at the host level have motivated a conservation paradigm of eradication, moving us farther from attainment of taxonomically unbiased conservation goals. Despite a growing body of literature highlighting the importance of parasite‐inclusive conservation, most parasite species remain understudied, underfunded, and underappreciated. We argue the protection of parasitic biodiversity requires a paradigm shift in the perception and valuation of their role as consumer species, similar to that of apex predators in the mid‐20th century. Beyond recognizing parasites as vital trophic regulators, existing tools available to conservation practitioners should explicitly account for the unique threats facing dependent species. We built upon concepts from epidemiology and economics (e.g., host‐density threshold and cost‐benefit analysis) to devise novel metrics of margin of error and minimum investment for parasite conservation. We define margin of error as the risk of accidental host extinction from misestimating equilibrium population sizes and predicted oscillations, while minimum investment represents the cost associated with conserving the additional hosts required to maintain viable parasite populations. This framework will aid in the identification of readily conserved parasites that present minimal health risks. To establish parasite conservation, we propose an extension of population viability analysis for host–parasite assemblages to assess extinction risk. In the direst cases, ex situ breeding programs for parasites should be evaluated to maximize success without undermining host protection. Though parasitic species pose a considerable conservation challenge, adaptations to conservation tools will help protect parasite biodiversity in the face of an uncertain environmental future.     

The silvering process of European eel (Anguilla anguilla) influences PAH metabolite concentrations in bile fluid: consequences for monitoring

The stock of the catadromous European eel (Anguilla anguilla L.) continues to decline and there is growing evidence that poor health status due to contaminants might be a key element in this decrease. Organic contaminants such as polycyclic aromatic hydrocarbons (PAHs) belong to the major threats to yellow eel in their growth habitat and their metabolites are detectable in the bile. Starting the silvering process eels undergo physiological and morphological changes including cessation of feeding and downstream migration back to their spawning grounds. Reduced feed intake results in a diminishment of bile production and induces accumulation of e.g. PAH-metabolites in bile. Therefore, the aim of the present study was to demonstrate the impact of silvering on biliary PAH metabolite concentrations and to utilize normalization procedures to overcome silvering related accumulation effects of PAH-metabolites in eel bile. We investigated the hydroxyl-metabolites of pyrene (1-OH Pyr) and phenantrene (1-OH Phen) in the bile of different maturation stages of eels (silvering index I-V) from nine German rivers. We detected increasing absolute PAH metabolite levels in bile during the silvering process. The highest rise could be observed at the transition from pre migration stage III to the migrating stage IV, suggesting the onset of cessation of feeding at this stage. A cessation bias in PAH metabolite measurement could be diminished by normalization of absolute values against bile pigments (A₃₈₀, biliverdin). In conclusion, we demonstrated the impact of silvering on PAH metabolite concentrations in eel bile and present suitable normalization procedures to overcome silvering related accumulation effects. Thus, for a future eel monitoring we recommend (1) to regularly monitor PAH metabolites in bile, (2) to determine silvering index of eel and (3) to normalize PAH metabolite values in bile based on maturation/silvering stages. The knowledge of the silvering stage is mandatory for an unbiased evaluation of PAH contamination of European eel towards an international harmonized eel monitoring program.     

新型结构ABR的设计与水力特性研究

针对ABR自身的缺点,设计出一种新型结构的ABR.该反应器为双层结构,共有5部分组成,各部分容积各不相同.该反应器的设计思想是将ABR与生物滤池以及活性炭吸附等工艺相联合.这种设计能够最大程度地发挥各工艺的优势,进而达到更好的处理效果.通过脉冲响应实验对该反应器的水力特性进行研究,得出不同水力停留时间(HRT)下的停留...     

Adsorption of Pb(II) on variable charge soils amended with rice-straw derived biochar

Two Ultisols and one Oxisol from tropical regions of southern China were incubated with rice straw biochar to investigate the effect of biochar on their surface charge and Pb(II) adsorption using batch methods. The incorporation of biochar induced a remarkable increase in soil cation exchange capacity after 30 d of incubation. The incorporation of biochar significantly increased the adsorption of Pb(II) by these variable charge soils; the enhancement of adsorption of Pb(II) by these soils increased with the addition level of biochar. Adsorption of Pb(II) involved both electrostatic and non-electrostatic mechanisms; however, biochar mainly increased Pb(II) adsorption through the non-electrostatic mechanism via the formation of surface complexes between Pb²⁺ and functional groups on biochar. There was greater enhancement of biochar on the non-electrostatic adsorption of Pb(II) by the variable charge soils at relatively low pH. Therefore, the incorporation of biochar decreased the activity and availability of Pb(II) to plants through increased non-electrostatic adsorption of Pb(II) by acidic variable charge soils.     

HRT对固定床厌氧反应器运行效果的影响

为了考察水力停留时间(HRT)对炭纤维载体固定床厌氧反应器运行效果的影响,在进水COD分别为20 000~25 000 mg/L和40 000~45 000 mg/L2个浓度范围下,研究了不同HRT对反应器运行效果的影响。结果表明,通过HRT的调整,在达到相同有机负荷(OLR)下,进水COD为20 000~25 000 mg/L的COD去除率和产气量,明显比进水COD为40 000~45 000 mg/L的运行效果好;进水COD为20 000~25 000 mg/L,HRT为14 h,相应的OLR为41.09 kgCOD/(m3.d)时,COD去除率仍然维持在68%以上,沼气容积产气率达到14.55 m3/(m3.d)。炭纤维载体固定床厌氧反应器具有较高的COD去除率、产气效率以及抵抗低pH、高负荷冲击的能力,运行过程中没有发生反应器堵塞的现象。     

祁连山北坡自然恢复杨桦林地植物功能型组成及其影响因素

依据生活型(乔木、藤本、灌木、半灌木、多年生禾草、多年生杂类草和一二年生草本)和水分生态型(旱生、旱中生、中生和湿生)将祁连山北坡次生杨桦林28个调查样地中的81个物种划分为18种植物功能型(Plant functiontypes,PFTs),并通过典范对应分析(CCA)方法研究植物功能型与环境因子间的关系.结果表明:自然恢复杨桦林地植物功能型主要集中在中生多年生杂类草(PFTs16)、湿生多年生杂类草(PFTs23)、旱中生多年生杂类草(PFTs9)和中生灌木(PFTs18)4个植物功能型上;乔、灌、草三层冠层特征和中生植物的大量出现,反映了群落植物生活型趋于复杂化和结构化,生态型逐渐向中生化方向演替的特点;土壤容重、有机碳和全氮含量主要影响植物的生活型分异特征,土壤含水量和林冠郁闭度是植物的水分生态型分异的主要环境因子,而坡位、坡度控制着群落植物总体分布格局的形成.图1表3参31