Evolution-based approach needed for the conservation and silviculture of peripheral forest tree populations

The fate of peripheral forest tree populations is of particular interest in the context of climate change. These populations may concurrently be those where the most significant evolutionary changes will occur; those most facing increasing extinction risk; the source of migrants for the colonization of new areas at leading edges; or the source of genetic novelty for reinforcing standing genetic variation in various parts of the range. Deciding which strategy to implement for conserving and sustainably using the genetic resources of peripheral forest tree populations is a challenge. Here, we review the genetic and ecological processes acting on different types of peripheral populations and indicate why these processes may be of general interest for adapting forests and forest management to climate change. We particularly focus on peripheral populations at the rear edge of species distributions where environmental challenges are or will become most acute. We argue that peripheral forest tree populations are “natural laboratories” for resolving priority research questions such as how the complex interaction between demographic processes and natural selection shape local adaptation; and whether genetic adaptation will be sufficient to allow the long-term persistence of species within their current distribution. Peripheral populations are key assets for adaptive forestry which need specific measures for their preservation. The traditionally opposing views which may exist between conservation planning and sustainable forestry need to be reconciled and harmonized for managing peripheral populations. Based on existing knowledge, we suggest approaches and principles which may be used for the management and conservation of these distinctive and valuable populations, to maintain active genetic and ecological processes that have sustained them over time

THE IMPORTANCE OF WOODY PLANT INTRODUCTION FOR FOREST TREES IMPROVEMENT

The history of woody plant introduction is closely linked with that of transportationand the European exploration of the planet (16th–19th centuries). Each colonialpower established major botanical gardens and experimental stations in variousparts of the world. By the 20th century, the purpose of introductions shifted fromfood plants to timber and other species yielding non-agricultural products. Finally,during the latter part of the 20th century the importance of ornamental speciesincreased dramatically, especially to the more developed and wealthier regions.Over the past two centuries many species have started to spread in their introducedranges. Until relatively recently the majority of introduced woody species havebeen highly beneficial, if not essential, to humanity’s development, but now everincreasingnumbers of species are becoming detrimental to the maintenance of theearth’s biodiversity and to the well-being of human societies. Throughout the 19thand specially in 20th century the large-scale planting of trees for timber productionhas been one of the main reasons for the introductions of a large number of species,especially conifers e.g. Pinus, Picea. Pseudotsuga and Poplars and Willowsspecies. By using methods of mass and individual selection and by establishing ofprovenances tests, as well as by half and full sib lines of selected exotics test trees,genetical potential productivity and adaptability of introduced species have beentested in numerous experimental plots in areas where introduced have been done.This paper attempts to unravel the relationships between humans and woody plantsby looking at the changes in the introduction of species, the way they are perceivedby different human groups and the impact these non native species have on foresttrees improvement and other human activities

Effect of Herbicide Clopyralid and Imazamox on Dehydrogenase Enzyme in Soil of Regenerated Pedunculate Oak Forests

Clopyralid and imazamox are successfully used for weed control during the first years of regeneration of pedunculate oak forests. Hence, the question that arises is how these herbicides affect microorganisms, especially the activity of dehydrogenase enzyme, when they reach the soil. Two study sites were selected in regenerated pedunculate oak forests, and the two herbicides were applied in two doses that are used for weed control (clopyralid, 100 g a.i. ha−1 and 120 g a.i. ha−1; imazamox, 40 g a.i. ha−1 and 48 g a.i. ha−1). The effect of the herbicides was evaluated 7, 14, 21, 30, and 60 days after application. A significant reduction in dehydrogenase activity was found on days 7 and 14 at both sites. However, after 14 days there was a recovery of dehydrogenase activity for all treatments such that the values obtained on day 21 did not differ from the control values. The effect of clopyralid and imazamox on dehydrogenase activity was not dose-dependent. Dehydrogenase activity also depended on soil properties, soil sampling time and climatic conditions during the investigation years. The results show that clopyralid and imazamox can reduce soil dehydrogenase activity, but this effect is transient. This can be attributed to the ability of microorganisms to overcome the stress caused by the herbicide by developing the capability to utilize herbicides as a nutrient source and proliferating in such an environment

How Do Stakeholders Working on the Forest-Water Nexus Perceive Payments for Ecosystem Services?

Nowadays, great emphasis is placed on the relationship between forest and water because forests are considered as substantial sources of many water ecosystem services. The aim of this paper is to analyze the stakeholder opinions towards the relationship between forests and water and the potential development of water-related payments for ecosystem services (PES) schemes. The study is developed in the context of COST Action CA15206-PESFOR-W (Forests for Water) aimed at synthesizing current knowledge about the PES schemes across Europe. The stakeholder opinions were mapped out using a structured questionnaire consisting of 20 questions divided into four thematic sections. The data were collected through an online survey. The results showed opinions of 142 stakeholders from 23 countries, mainly from Eastern Europe and the Mediterranean Basin. In order to analyze the collected data, the stakeholders were grouped in buyers, sellers, intermediaries, and knowledge providers. The survey results indicated that the most important category of water ecosystem services according to our sample of stakeholders is regulating services followed by provisioning services. Further findings pointed out the highest importance that shared values and direct changes in land management can have when designing water-related PES schemes. The role of public authorities and collective collaboration of different stakeholders, with emphasis on local and expert knowledge, are also identified as of crucial importance. The results show that stakeholder opinions can serve as a starting point when designing PES schemes

Disentangling climate from soil nutrient effects on plant biomass production using a multispecies phytometer

Plant community biomass production is co-dependent on climatic and edaphic factors that are often covarying and non-independent. Disentangling how these factors act in isolation is challenging, especially along large climatic gradients that can mask soil effects. As anthropogenic pressure increasingly alters local climate and soil resource supply unevenly across landscapes, our ability to predict concurrent changes in plant community processes requires clearer understandings of independent and interactive effects of climate and soil. To address this, we developed a multispecies phytometer (i.e., standardized plant community) for separating key drivers underlying plant productivity across gradients. Phytometers were composed of three globally cosmopolitan herbaceous perennials, Dactylis glomerata, Plantago lanceolata, and Trifolium pratense. In 2017, we grew phytometer communities in 18 sites across a pan-European aridity gradient in local site soils and a standardized substrate and compared biomass production. Standard substrate phytometers succeeded in providing a standardized climate biomass response independent of local soil effects. This allowed us to factor out climate effects in local soil phytometers, establishing that nitrogen availability did not predict biomass production, while phosphorus availability exerted a strong, positive effect independent of climate. Additionally, we identified a negative relationship between biomass production and potassium and magnesium availability. Species-specific biomass responses to the environment in the climate-corrected biomass were asynchronous, demonstrating the importance of species interactions in vegetation responses to global change. Biomass production was co-limited by climatic and soil drivers, with each species experiencing its own unique set of co-limitations. Our study demonstrates the potential of phytometers for disentangling effects of climate and soil on plant biomass production and suggests an increasing role of P limitation in the temperate regions of Europe

ConservePlants : an integrated approach to conservation of threatened plants for the 21st century

Even though plants represent an essential part of our lives offering exploitational, supporting and cultural services, we know very little about the biology of the rarest and most threatened plant species, and even less about their conservation status. Rapid changes in the environment and climate, today more pronounced than ever, affect their fitness and distribution causing rapid species declines, sometimes even before they had been discovered. Despite the high goals set by conservationists to protect native plants from further degradation and extinction, the initiatives for the conservation of threatened species in Europe are scattered and have not yielded the desired results. The main aim of this Action is to improve plant conservation in Europe through the establishment of a network of scientists and other stakeholders who deal with different aspects of plant conservation, from plant taxonomy, ecology, conservation genetics, conservation physiology and reproductive biology to protected area's managers, not forgetting social scientists, who are crucial when dealing with the general public.peer-reviewe