Eradication of Invasive Mammals on Islands Inhabited by Humans and Domestic Animals

Abstract: Non‐native invasive mammal species have caused major ecological change on many islands. To conserve native species diversity, invasive mammals have been eradicated from several islands not inhabited by humans. We reviewed the challenges associated with campaigns to eradicate invasive mammals from islands inhabited by humans and domestic animals. On these islands, detailed analyses of the social, cultural, and economic costs and benefits of eradication are required to increase the probability of local communities supporting the eradication campaign. The ecological benefits of eradication (e.g., improvement of endemic species’ probability of survival) are difficult to trade‐off against social and economic costs due to the lack of a common currency. Local communities may oppose an eradication campaign because of perceived health hazards, inconvenience, financial burdens, religious beliefs, or other cultural reasons. Besides these social challenges, the presence of humans and domestic animals also complicates eradication and biosecurity procedures (measures taken to reduce the probability of unwanted organisms colonizing an island to near zero). For example, houses, garbage‐disposal areas, and livestock‐feeding areas can provide refuges for certain mammals and therefore can decrease the probability of a successful eradication. Transport of humans and goods to an island increases the probability of inadvertent reintroduction of invasive mammals, and the establishment of permanent quarantine measures is required to minimize the probability of unwanted recolonization after eradication. We recommend a close collaboration between island communities, managers, and social scientists from the inception of an eradication campaign to increase the probability of achieving and maintaining an island permanently free of invasive mammals.     

Generality of Models that Predict the Distribution of Species: Conservation Activity and Reduction of Model Transferability for a Threatened Bustard

Abstract:  Predictive models can help clarify the distribution of poorly known species but should display strong transferability when applied to independent data. Nevertheless, model transferability for threatened tropical species is poorly studied. We built models predicting the incidence of the critically endangered Bengal Florican ( Houbaropsis bengalensis ) within the Tonle Sap (TLS) floodplain, Cambodia. Separate models were constructed with soil, land-use, and landscape data and species incidence sampled over the entire floodplain (12,000 km²) and from the Kompong Thom (KT) province (4000 km²). In each case, the probability of Bengal Florican presence within randomly selected 1 × 1 km squares was modeled by binary logistic regression with multimodel inference. We assessed the transferability of the KT model by comparing predictions with observed incidence elsewhere in the floodplain. In terms of standard model-validation statistics, the KT model showed good spatial transferability. Nevertheless, it overpredicted florican presence outside the KT calibration region, classifying 491 km² as suitable habitat compared with 237 km² predicted as suitable by the TLS model. This resulted from higher species incidence within the calibration region, probably owing to a program of conservation education and enforcement that has reduced persecution there. Because both research and conservation activity frequently focus on areas with higher density, such effects could be widespread, reducing transferability of predictive distribution models.     

The Use of Ecologically Based Screening Criteria in a Community-sponsored Open Space Preservation Programme

The Meridian Township Land Preservation Programme is the first community-sponsored, open space and natural areas preservation programme in Michigan using ecological principles in the ranking of properties for acquisition. The programme was established through a collaborative, multi-stakeholder effort that resulted in a model ordinance, operating procedures, guidelines for landowners to nominate their properties for consideration, and a set of criteria for property selection. The screening criteria include ecological value, natural or functional value, parcel size, surrounding land use, environmental quality, and aesthetic value. The criteria were developed to reflect principles established by landscape ecology and land conservation objectives to maintain a maximum degree of biodiversity and to develop, manage and maintain ecological infrastructure through management of protected areas. The programme is entirely funded through a local millage, which will raise nearly $10 million over 10 years. The target for acquisition of open space is approximately 10% of the currently undeveloped parcels in the township.     

Shrinking Tropical Forests, Human Agents of Change, and Conservation Policy

Abstract:  Human agents of landscape transformation in the tropics affect forests differently as the forests decline in size. Five agents of change—road builders, corporate concession holders, community forest managers, park advocates, and urban consumers—have different effects on large forests in remote tropical regions than they do on remnant forests in settled agricultural regions. Because forests vary so much in size across tropical regions, these differences in the effects of agents on forests have important implications for regional conservation efforts. To make these implications explicit, I compared the effects of the five agents in regions with large forests with their effects in regions with small forests. The comparisons indicated that, as forests declined in size, new roads no longer destroyed forests, corporate loggers left the forests, community forest managers became more effective, parks became less feasible as a means of conservation, and urban consumers initiated tree planting. My results suggest that awareness about the changing effects of humans on landscapes with shrinking forests can serve as a useful tool in formulating regionally appropriate policies for conserving tropical forests.     

Permanent Sovereignty over Natural Resources Recent Developments in the Mineral Sector

The United Nations has been concerned with the application of the principle of permanent sovereignty over natural resources and the exercise by developing countries of control over the exploitation of their natural resources for many years. Probably the most serious concern in recent years has been the impact of the world-wide recession on investment in mineral exploration and production facilities in developing countries. Growing difficulties in attracting investment funds have caused a re-examination of existing investment, mining and tax legislation. Recent mineral development agreements assign a higher priority to investment promotion; this reflects a change from earlier years—during the 1960s and 1970s—when many developing countries were in a stronger position because equity and loan capital for mineral projects was more readily available. Pendant de nombreuses années, les Nations Unies se sont préoccupées de la mise en oeuvre par les pays en développement du principe de leur souveraineté permanente sur leurs ressources naturelles ainsi que de l'exercice de leur droit de contrôle sur la mise en production de ces mêmes ressources. En toute vraisemblance, le problème le plus sérieux qui s'est posé au cours de ces dernières années a été le poids de la récession économique mondiale sur les investissements dans les domaines de l'exploration et de la production minières dans les pays en développement. Les difficultés grandissantes à obtenir des capitaux ont conduit à réexaminer les investissements existants ainsi que la législation minière et fiscale. De récents accords de développement minier réservent une priorité plus importante à la promotion des investissements. Ceci reflète un changement par rapport aux années précédentes—celles des décennies 60 et 70—au cours desquelles de nombreux pays en développement avaient une position beaucoup plus forte car il était plus facile de trouver des capitaux propres et des prêts financiers pour les projets miniers. Las Naciones Unidas ha estado interesado en la aplicación del principio de soveranía permanente de los recursos naturales y el ejercicio del control por parte de los países en desarrollo sobre su explotación. Probablemente la mayor preocupación en an?os recientes ha sido el impacto de la recesión mundial de las inversiones en la exploración y producción de minerales en los países en desarrollo. La dificultad creciente en atraer inversiones ha motivado el examen de la legislación existente sobre inversiones, minería e impuestos. Recientes acuerdos sobre desarrollo de minerales asigna mayor prioridad a la promoción de inversiones; esto representa un cambio con respecto a an?os anteriores—décadas del 60 y 70—cuando los países en desarrollo tenían una posición fuerte debido a que el capital de riesgo y préstamos para proyectos en minería eran abundante.     

城市污水处理厂好氧颗粒污泥的特性

对城市污水处理厂曝气池中筛选出的好氧颗粒污泥进行了分析.结果表明,这些颗粒污泥的直径主要在0.2～0.8 mm范围;平均圆度为1.29;沉淀速率约在10～42 m h-1之间;比耗氧速率(SOUR)为14.2～18.9 mg g-1h-1,小于活性污泥;挥发性物质占总固体的量与活性污泥基本相似.这些颗粒污泥占污泥总量的0.1%～0.5%.颗粒污泥的激光共聚焦扫描显微镜(CLSM)图像显示:颗粒污泥内部几乎都由胞外聚合物(EPS)组成;细菌主要分布在颗粒污泥表面至100μm厚度区域,少部分分布在100～400μm厚度区域.     

Modeling the Effects of Anthropogenic Habitat Change on Savanna Snake Invasions into African Rainforest

Abstract:  We used a species-distribution modeling approach, ground-based climate data sets, and newly available remote-sensing data on vegetation from the MODIS and Quick Scatterometer sensors to investigate the combined effects of human-caused habitat alterations and climate on potential invasions of rainforest by 3 savanna snake species in Cameroon, Central Africa: the night adder (Causus maculatus) , olympic lined snake (Dromophis lineatus) , and African house snake (Lamprophis fuliginosus) . Models with contemporary climate variables and localities from native savanna habitats showed that the current climate in undisturbed rainforest was unsuitable for any of the snake species due to high precipitation. Limited availability of thermally suitable nest sites and mismatches between important life-history events and prey availability are a likely explanation for the predicted exclusion from undisturbed rainforest. Models with only MODIS-derived vegetation variables and savanna localities predicted invasion in disturbed areas within the rainforest zone, which suggests that human removal of forest cover creates suitable microhabitats that facilitate invasions into rainforest. Models with a combination of contemporary climate, MODIS- and Quick Scatterometer-derived vegetation variables, and forest and savanna localities predicted extensive invasion into rainforest caused by rainforest loss. In contrast, a projection of the present-day species-climate envelope on future climate suggested a reduction in invasion potential within the rainforest zone as a consequence of predicted increases in precipitation. These results emphasize that the combined responses of deforestation and climate change will likely be complex in tropical rainforest systems.