Cryptic herbivores mediate the strength and form of ungulate impacts on a long-lived savanna tree

Plant populations are regulated by a diverse array of herbivores that impose demographic filters throughout their life cycle. Few studies, however, simultaneously quantify the impacts of multiple herbivore guilds on the lifetime performance or population growth rate of plants. In African savannas, large ungulates (such as elephants) are widely regarded as important drivers of woody plant population dynamics, while the potential impacts of smaller, more cryptic herbivores (such as rodents) have largely been ignored. We combined a large-scale ungulate exclusion experiment with a five-year manipulation of rodent densities to quantify the impacts of three herbivore guilds (wild ungulates, domestic cattle, and rodents) on all life stages of a widespread savanna tree. We utilized demographic modeling to reveal the overall role of each guild in regulating tree population dynamics, and to elucidate the importance of different demographic hurdles in driving population growth under contrasting consumer communities. We found that wild ungulates dramatically reduced population growth, shifting the population trajectory from increase to decline, but that the mechanisms driving these effects were strongly mediated by rodents. The impact of wild ungulates on population growth was predominantly driven by their negative effect on tree reproduction when rodents were excluded, and on adult tree survival when rodents were present. By limiting seedling survival, rodents also reduced population growth; however, this effect was strongly dampened where wild ungulates were present. We suggest that these complex interactions between disparate consumer guilds can have important consequences for the population demography of long-lived species, and that the effects of a single consumer group are often likely to vary dramatically depending on the larger community in which interactions are embedded.     

Approaches to integrated water resource development and management

In southern Africa institutional capacity in the water sector is severely limited by diminishing regular budget and external assistance allocations. The result has been an overall decline in operational water resource management. This is ironic given the international community's current concern with 'integrated' or 'comprehensive' water resources management. Often, so-called integrated attempts at river basin planning and development have been conceived within the framework of a river basin authority or regional master plans. Such large-scale attempts have not necessarily been compatible either with the national capacity in water resources management or the existing institutional and legislative frameworks. In many cases the actual integration of a basin's physical resources and social, economic and environmental demands is poorly executed. To examine a way forward in resolving what is clearly an unsustainable state of affairs, a diagnostic study of the Kafue Basin, Zambia, was carried out in order to identify a set of water resource management options for a basin currently under stress. A physical framework for the Kafue Basin was established and principal subcatchments and hydro-geological subsystems identified. Current water resource issues in the basin are discussed and a multiobjective approach is proposed to allow intersectoral competition for the basin's limited water resources to be reconciled.     

Identification of chlordane compounds in harbour seals from the coastal waters of the Netherlands

In a study of two unknown compounds in blubber of harbour seals (Phoca vitulina) of the Dutch North Sea coast combined capillary gas chromaiographic mass spectrometric data indicated the presence of trans-nonachlor and oxychlordane. These compounds have never been identified in environmental biota in The Netherlands before.     

Gravity orientation in social wasp comb cells (Vespinae) and the possible role of embedded minerals

Social wasps and hornets maintain their nest in the dark. The building of the combs by all Vespinae is always in the direction of the gravitational force of Earth, and in each cell's ceiling, at least one 'keystone' is embedded and fastened by saliva. The sensory mechanisms that enable both building of sizeable symmetrical combs and nursing of the brood in the darkness merit investigation, and the aim of the present study was to identify and characterize the 'keystones' that exist in the ceiling and in the walls of the social wasp comb cells. Bio-ferrography was used to isolate magnetic particles on slides. These slides, as well as original cells, were analyzed in an environmental scanning electron microscope by a variety of analytical tools. It was found that both the roof and the walls of each comb cell bear minerals, like ferrites, as well as Ti and Zr. The latter two elements are less abundant in the soil around the nest. Ti and Zr are known to reflect infrared (IR) light. IR imaging showed a thermoregulatory center in the dorsal thorax of the adult Oriental hornet. It is not known yet whether these insects can sense IR light.     

The energetic costs of stereotyped behavior in the paper wasp, Polistes dominulus

Polistes wasps engage in many behavioral interactions. Although there has been debate over the meaning of these interactions, these stereotypical behaviors can be used to determine a colony’s linear dominance hierarchy. Due to the implicit relationship between behavioral and reproductive dominance, behavioral interactions are commonly used to distinguish the reproductively dominant alpha foundress from the beta foundress. It has been suggested that in order to maintain reproductive control, the alpha foundress is forced to remain at a physiologically constrained activity limit. This, in turn, may allow aggressive interactions to be used as determinants influencing reproductive partitioning between cooperating individuals. Energetic costs can place important limitations on behavior, but the energetic cost of the interactions has not previously been measured. To address this, we measured the CO₂ production of 19 non-nestmate pairs displaying interactive and noninteractive behavior. The rate of energy used during interaction behavior was positively associated with published rankings of aggression. However, our results indicate that interactions are not very energetically costly in Polistes, particularly when compared to the likely cost of foraging. These data suggest that maintaining reproductive dominance is not very energetically expensive for the dominant and that the dominant foundress expends energy at a lower rate than the subordinate foundress. Electronic Supplementary Material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Statistical and Hybrid Methods Implemented in a Web Application for Predicting Reservoir Inflows during Flood Events

Reservoir management is a critical component of flood management, and information on reservoir inflows is particularly essential for reservoir managers to make real‐time decisions given that flood conditions change rapidly. This study's objective is to build real‐time data‐driven services that enable managers to rapidly estimate reservoir inflows from available data and models. We have tested the services using a case study of the Texas flooding events in the Lower Colorado River Basin in November 2014 and May 2015, which involved a sudden switch from drought to flooding. We have constructed two prediction models: a statistical model for flow prediction and a hybrid statistical and physics‐based model that estimates errors in the flow predictions from a physics‐based model. The study demonstrates that the statistical flow prediction model can be automated and provides acceptably accurate short‐term forecasts. However, for longer term prediction (2 h or more), the hybrid model fits the observations more closely than the purely statistical or physics‐based prediction models alone. Both the flow and hybrid prediction models have been published as Web services through Microsoft's Azure Machine Learning (AzureML) service and are accessible through a browser‐based Web application, enabling ease of use by both technical and nontechnical personnel.     

Les Reciproqueteurs: post-regulatory corporatism

ABSTRACT

Reflexive governance can be understood as an emergent encapsulated trust-building corporatism where network participants are neither state functionaries nor market entrepreneurs but network reciproqueteurs. This paper argues that such reflexive network governance results in a post-regulatory corporatism (PRC)—a more adaptable, less formalized, and flexible mode of interest intermediation, policy-making, and policy-implementation than previous modes of corporatist intermediation. Functional differentiation processes engender ‘negotiated connected contracts' in rescaled space in between inter-regional assemblages, a mode of structurally coupling new social partners in the emergent transnational knowledge-based economy. This involves the building of new social capital of network trust-building manifested in the norms of reciprocity and reflexive law constituted as a new mode of protocolism: one associated with the social learning and policy designing necessary for ecological systems' autopoeisis, resilience, and sustainability. This paper conceptualizes reflexive network governance as protocolism in constellations of PRC and discusses examples from the area of environmental policy-making. PRC is understood as a new mode of negotiated rule-making: as a recursive protocolism of multi-stakeholder social pacts constituted by frame agreements and negotiated connected network contracts.