Assessing nitrogen and phosphorus removal potential of five plant species in floating treatment wetlands receiving simulated nursery runoff

The feasibility of using floating treatment wetlands (FTWs) to treat runoff typical of commercial nurseries was investigated using two 8-week trials with replicated mesocosms. Plants were supported by Beemat rafts. Five monoculture treatments of Agrostis alba (red top), Canna × generalis ‘Firebird’ (canna lily), Carex stricta (tussock sedge), Iris ensata ‘Rising Sun’ (Japanese water iris), Panicum virgatum (switchgrass), two mixed species treatments, and an unplanted control were assessed. These plant species are used for ornamental, wetland, and biofuel purposes. Nitrogen (N) and phosphorus (P) removals were evaluated after a 7-day hydraulic retention time (HRT). N removal (sum of ammonium-N, nitrate-N, and nitrite-N) from FTW treatments ranged from 0.255 to 0.738 g·m^?2·d^?1 (38.9 to 82.4% removal) and 0.147 to 0.656 g·m^?2·d^?1 (12.9 to 59.6% removal) for trials 1 and 2, respectively. P removal (phosphate-P) ranged from 0.052 to 0.128 g·m^?2·d^?1 (26.1 to 64.7% removal) for trial 1, and 0.074 to 0.194 g·m^?2·d^?1 (26.8 to 63.2% removal) for trial 2. Panicum virgatum removed more N and P than any other FTW treatment and the control in both trials. Results show that species selection and timing of FTW harvest impact the rate and mass of nutrient remediation. FTWs can effectively remove N and P from runoff from commercial nurseries.

     

Small farm ponds: overlooked features with important impacts on watershed sediment transport

Despite their size, small farm ponds are important features in many landscapes. Yet hydrographical databases often fail to capture these ponds, and their impacts on watershed processes remain unclear. For a 230‐km² portion of central Texas, United States (U.S.), we created a historical inventory of ponds and quantified the accuracy of automated detection methods under varying drought conditions. In addition, we documented pond dredging/enlargement events and identified sites that had been abandoned. We also analyzed sediment cores from downstream reservoirs to track changes in watershed sediment transport. Over 75 years, pond densities increased more than 350% — to among the highest documented in the U.S. — and the ability of automated methods to detect these ponds was highly dependent on drought severity (R² = 0.96). Approximately 5% of ponds present in the 1950s were no longer present in 2012, while 33% were dredged between 1937 and 2012. Downstream reservoir sedimentation has decreased by an average of 55% as ponds have increased in number. These findings suggest that small ponds and the maintenance of trapping efficiency have large‐scale impacts on sediment dynamics. Accurately accounting for these storage effects is vital to water resource planning efforts.     

Crowded skies: Conflicts between expanding goose populations and aviation safety

We here review the collision risks posed by large-bodied, flocking geese to aircraft, exacerbated by recent major increases in northern hemisphere goose populations and air traffic volume. Mitigation of goose–aircraft strike risks requires knowledge of local goose movements, global goose population dynamics and ecology. Airports can minimise goose strikes by managing habitats within the airport property, applying deterrents to scare geese away and lethal control, but goose migration and movements at greater spatial scales present greater challenges. Habitat management outside of airports can locally reduce goose attractiveness of peripheral areas, but requires stakeholder involvement and coordination. Information on bird strike rates, individual goose movements and goose population dynamics is essential to understand how best to reduce the risk of goose strikes. Avian radar provides tactical information for mitigation measures and strategic data on local patterns of goose migration and habitat use. In the face of expanding air traffic, goose distributions and populations, these threats need to be integrated with other local, national and international stakeholder involvement to secure viable solutions to multiple conflicts.     

Why geese benefit from the transition from natural vegetation to agriculture

The energy and nutrient content of most agricultural crops are as good as or superior to natural foods for wild geese and they tend to be available in agricultural landscapes in far greater abundance. Artificial grasslands (fertilised native swards and intensively managed reseeds) offer far superior quality forage and higher intake rates than seminatural or natural grasslands. The availability of such abundant artificial food explains the abandonment of traditional habitats for farmland by geese over the last 50–100 years and favours no reduction in current levels of exploitation of agriculture. Continental scale spatial and temporal shifts among geese undergoing spring fattening confirm their flexibility to respond rapidly to broadscale changes in agriculture. These dramatic changes support the hypothesis that use of agricultural landscapes has contributed to elevated reproductive success and that European and North American farmland currently provides unrestricted winter carrying capacity for goose populations formerly limited by wetlands habitats prior to the agrarian revolution of the last century.     

Hydroxypropyl-β-cyclodextrin as non-exhaustive extractant for organochlorine pesticides and polychlorinated biphenyls in muck soil

Hydroxypropyl-β-cyclodextrin (HPCD) was used as a non-exhaustive extractant for organochlorine pesticides (OCs) and polychlorinated biphenyls (PCBs) in muck soil. An optimized extraction method was developed which involved using a HPCD to soil mass ratio of 5.8 with a single extraction period of 20 h. An aging experiment was performed by spiking a muck soil with ¹³C-labeled OCs and non-labeled PCBs. The soil was extracted with the optimized HPCD method and Soxhlet apparatus with dichloromethane over 550 d periodically. The HPCD extractability of the spiked OCs was greater than of the native OCs. A decreased in HPCD extractability was observed for the spiked OCs after 550 d of aging and their extractability approached those of the natives. The partition coefficient between HPCD and soil (log K_CD-Soil) was negatively correlated with the octanol-water partition coefficient (log K_OW) with r² = 0.67 and p < 0.05.     

Brominated flame retardants in the Australian population: 1993-2009

Brominated flame retardants, including hexabromocyclododecane (HBCD) and polybrominated diphenyl ethers (PBDEs) are used to reduce the flammability of a multitude of electrical and electronic products, textiles and foams. The use of selected PBDEs has ceased, however, use of decaBDE and HBCD continues. While elevated concentrations of PBDEs in humans have been observed in Australia, no data is available on other BFRs such as HBCD. This study aimed to provide background HBCD concentrations from a representative sample of the Australian population and to assess temporal trends of HBCD and compare with PBDE concentrations over a 16 year period. Samples of human milk collected in Australia from 1993 to 2009, primarily from primiparae mothers were combined into 12 pools from 1993 (2 pools); 2001; 2002/2003 (4 pools); 2003/2004; 2006; 2007/2008 (2 pools); and 2009. Concentrations of ∑HBCD ranged from not quantified (nq) to 19 ng g(-1)lipid while α-HBCD and γ-HBCD ranged from nq to 10 ng g(-1)lipid and nq to 9.2 ng g(-1)lipid. β-HBCD was detected in only one sample at 3.6 ng g(-1)lipid while ∑(4)PBDE ranged from 2.5 to 15.8 ng g(-1)lipid. No temporal trend was apparent in HBCD concentrations in human milk collected in Australia from 1993 to 2009. In comparison, PBDE concentrations in human milk show a peak around 2002/03 (mean ∑(4)PBDEs=9.6 ng g(-1)lipid) and 2003/04 (12.4 ng g(-1)lipid) followed by a decrease in 2007/08 (2.7 ng g(-1)lipid) and 2009 (2.6 ng g(-1)lipid). In human blood serum samples collected from the Australian population, PBDE concentrations did not vary greatly (p=0.441) from 2002/03 to 2008/09. Continued monitoring including both human milk and serum for HBCD and PBDEs is required to observe trends in human body burden of HBCD and PBDEs body burden following changes to usage.     

New Humanitarianism: Does It Provide a Moral Banner for the 21st Century?

There is a 'new humanitarianism' for the new millennium. It is 'principled', 'human-rights based' and politically sensitive. Above all it is new. It marks a break from the past and a rejection of the traditional principles that guided humanitarianism through the last century. New humanitarians reject the political naivety of the past, assess the long-term political impact of relief and are prepared to see humanitarian aid used as a tool to achieve human rights and political goals. New Humanitarianism is compelling, in tune with our times and offers a new moral banner for humanitarians to cling to as we enter the new millennium. Or does it? After outlining the key elements of new humanitarianism, including the human rights approach and developmental relief, the paper spells out some of the dangers. The author claims that new humanitarianism results in an overt politicisation of aid in which agencies themselves use relief as a tool to achieve wider political goals. The paper shows how this approach has spawned a new conditionality which allowsfor aid to be withheld and has produced a moral hierarchy of victims in which some are more deserving than others. The paper concludes with a plea for a revival of the principle of universalism as the first step to a new set of principles.     

Simulating Unstressed Crop Development and Growth Using the Unified Plant Growth Model (UPGM)

Since initial development of the EPIC model in 1989, the EPIC plant growth component has been incorporated into other erosion and crop management models (e.g., WEPS, WEPP, SWAT, ALMANAC, and GPFARM) and subsequently modified to meet research objectives of the model developers. This has resulted in different versions of the same base plant growth component. The objectives of this study are the following: (1) describe the standalone Unified Plant Growth Model (UPGM), initially derived from the WEPS plant growth model, to be used for merging enhancements from other EPIC-based plant growth models; and (2) describe and evaluate new phenology, seedling emergence, and canopy height sub-models derived from the Phenology Modular Modeling System (PhenologyMMS V1.2) and incorporated into UPGM. A 6-year (2005–2010) irrigated maize (Zea mays L.) study from northeast Colorado was used to calibrate and evaluate UPGM running both the original (i.e., based on WEPS) and new phenology, seedling emergence, and canopy height sub-models. Model statistics indicated the new sub-models usually resulted in better simulation results than the original sub-models. For example when comparing original and new sub-models, respectively, for predicting canopy height, the root mean square error (RMSE) was 53.7 and 40.7 cm, index of agreement (d) was 0.84 and 0.92, relative error (RE) was 26.0 and ?1.26 %, and normalized objective function (NOF) was 0.47 and 0.33. The new sub-models predict leaf number (old sub-models do not), with mean values for 4 years of 2.43 leaves (RMSE), 0.78 (d), 18.38 % (RE), and 0.27 (NOF). Simulating grain yield, final above ground biomass, and harvest index showed little difference when running the original or new sub-models. Both the new phenology and seedling emergence sub-models respond to varying water deficits, increasing the robustness of UPGM for more diverse environmental conditions. Future research will continue working to incorporate existing enhancements from other EPIC-based plant growth models to unify them into one model such as multispecies competition and N cycling.     

Roads, Development, and Conservation in the Congo Basin

Abstract: Road density is closely linked to market accessibility, economic growth, natural resource exploitation, habitat fragmentation, deforestation, and the disappearance of wildlands and wildlife. Research in the Republic of Congo shows that roads established and maintained by logging concessions intensify bushmeat hunting by providing hunters greater access to relatively unexploited populations of forest wildlife and by lowering hunters' costs to transport bushmeat to market. Reconciling the contrary effects of roads on economic development and biodiversity conservation is one of the key challenges to wildlife managers in all nations. As the Democratic Republic of Congo prepares to reconstruct its almost completely collapsed road system, the government, donors, and conservation organizations have a unique opportunity to strategically prioritize investment in segments of the network that would maximize local and national economic benefits while minimizing adverse effects on forest wildlife.     

The consequences of poaching and anthropogenic change for forest elephants

Poaching has devastated forest elephant populations (Loxodonta cyclotis), and their habitat is dramatically changing. The long‐term effects of poaching and other anthropogenic threats have been well studied in savannah elephants (Loxodonta africana), but the impacts of these changes for Central Africa's forest elephants have not been discussed. We examined potential repercussions of these threats and the related consequences for forest elephants in Central Africa by summarizing the lessons learned from savannah elephants and small forest elephant populations in West Africa. Forest elephant social organization is less known than the social organization of savannah elephants, but the close evolutionary history of these species suggests that they will respond to anthropogenic threats in broadly similar ways. The loss of older, experienced individuals in an elephant population disrupts ecological, social, and population parameters. Severe reduction of elephant abundance within Central Africa's forests can alter plant communities and ecosystem functions. Poaching, habitat alterations, and human population increase are probably compressing forest elephants into protected areas and increasing human–elephant conflict, which negatively affects their conservation. We encourage conservationists to look beyond documenting forest elephant population decline and address the causes of these declines when developing conversation strategies. We suggest assessing the effectiveness of the existing protected‐area networks for landscape connectivity in light of current industrial and infrastructure development. Longitudinal assessments of the effects of landscape changes on forest elephant sociality and behavior are also needed. Finally, lessons learned from West African elephant population loss and habitat fragmentation should be used to inform strategies for land‐use planning and managing human–elephant interactions.