Differentiation of the dynamic variables affecting rooting ability in juvenile and mature cuttings of cherry (Prunus avium)

The rooting potential of four types or origins of Prunus avium cuttings from the same mature trees (over 20 years-old) was compared using a mist propagation bed during early Summer (June).The cuttings originated from juvenile sucker shoots of the current and previous year, and mature crown shoots (current year's lateral `long-shoots' and multi-year terminal `short shoots').The morphological differences in inter-node length, stem diameter and leaf area between the four cutting types were highly significant (P = 0.05), leading to large differences in cutting volume and, so it is argued, to assimilate reserves. Juvenile cuttings rooted well (65% and 77% rooting for hardwood and softwood shoots, respectively), while mature cuttings rooted poorly (4% and 7% for mature hardwood and softwood cuttings, respectively). Leaf abscission was significantly more frequent in mature hardwood cuttings (16 - 78%) than in the other cutting types (1.6 - 9%) at the end of the propagation period. Leaf loss resulted from two processes: abscission and leaf rotting. Physiologically (i.e., in carbon assimilation, leaf transpiration and stomatal conductance), the four cutting types were not significantly different early in the post-severance period (day-4); but, by day-22, stomatal conductance was lowest in mature hardwood cuttings that still had leaves. At this time, the most physiologically-active unrooted cuttings were from juvenile hardwood and mature softwood shoots. The extent of physiological and morphological variability between cutting types and their probable impact on processes affecting rooting ability is complex and highly interactive. Consequently, it is not possible to explain the causes of the variation in rooting ability between juvenile and mature cuttings, although this study suggests that the constraints to rooting are likely to reflect physiological differences between the different cutting types. It is concluded that, to resolve the debate about factors that affect the rooting ability of juvenile and mature cuttings (i.e., ontogenetic vs. physiological ageing), there is a need to achieve morphological and physiological comparability in the tissues

How should regional biodiversity be monitored?

We consider quantification of biodiversity in the context of targets set by the Convention on Biological Diversity. Implicit in such targets is a requirement to monitor biodiversity at a regional level. Few monitoring schemes are designed with these targets in mind. Monitored sites are typically not selected to be representative of a wider region, and measures of biodiversity are often biased by a failure to account for varying detectability among species and across time. Precision is often not adequately quantified. We review methods for quantifying the biodiversity of regions, consider issues that should be addressed in designing and evaluating a regional monitoring scheme, and offer a practical guide to what types of survey are appropriate for addressing different objectives for biodiversity monitoring

Integrating health and environmental impact analysis

Scientific investigations have progressively refined our understanding of the influence of the environment on human health, and the many adverse impacts that human activities exert on the environment, from the local to the planetary level. Nonetheless, throughout the modern public health era, health has been pursued as though our lives and lifestyles are disconnected from ecosystems and their component organisms. The inadequacy of the societal and public health response to obesity, health inequities, and especially global environmental and climate change now calls for an ecological approach which addresses human activity in all its social, economic and cultural complexity. The new approach must be integral to, and interactive, with the natural environment. We see the continuing failure to truly integrate human health and environmental impact analysis as deeply damaging, and we propose a new conceptual model, the ecosystems-enriched Drivers, Pressures, State, Exposure, Effects, Actions or ‘eDPSEEA’ model, to address this shortcoming. The model recognizes convergence between the concept of ecosystems services which provides a human health and well-being slant to the value of ecosystems while equally emphasizing the health of the environment, and the growing calls for ‘ecological public health’ as a response to global environmental concerns now suffusing the discourse in public health. More revolution than evolution, ecological public health will demand new perspectives regarding the interconnections among society, the economy, the environment and our health and well-being. Success must be built on collaborations between the disparate scientific communities of the environmental sciences and public health as well as interactions with social scientists, economists and the legal profession. It will require outreach to political and other stakeholders including a currently largely disengaged general public. The need for an effective and robust science-policy interface has never been more pressing. Conceptual models can facilitate this by providing theoretical frameworks and supporting stakeholder engagement process simplifications for inherently complex situations involving environment and human health and well-being. They can be tools to think with, to engage, to communicate and to help navigate in a sea of complexity. We believe models such as eDPSEEA can help frame many of the issues which have become the challenges of the new public health era and can provide the essential platforms necessary for progress