An Overview of Larch/C++: Behavioral Specifications for C++ Modules

An overview is presented of the behavioral interface specification language Larch/C++. The features of Larch/C++ used to specify the behavior of C++ functions and classes, including subclasses, are described, with examples. Comparisons are made with other object-oriented specification languages. An innovation in Larch/C++ is the use of examples in function specifications. Copyright (c) Kluwer Academic Publishers, 1996. Used by permission. An abbreviated and earlier version of this paper is chapter 8 in the book Specification of Behavioral Semantics in Object-Oriented Information Modeling, edited by Haim Kilov and William Harvey (Kluwer Academic Publishers, 1996), pages 121-142

Component Composition in Business and System Modelling

Bespoke development of large business systems can be couched in terms of the composition of components, which are, put simply, chunks of development work. Design, mapping a specification to an implementation, can also be expressed in terms of components: a refinement comprising an abstract component, a concrete component and a mapping between them. Similarly, system extension is the composition of an existing component, the legacy system, with a new component, the extension. This paper overviews work being done on a UK EPSRC funded research project formulating and formalizing techniques for describing, composing and performing integrity checks on components. Although the paper focuses on the specification and development of information systems, the techniques are equally applicable to the modeling and re-engineering of businesses, where no computer system may be involved

Synergies of planning for forests and planning for Natura 2000: Evidences and prospects from northern Italy

Improvements in the management of Natura 2000 sites are essential to achieve the targets set out by the Habitats and Birds Directives of the European Union. A current focus is on the development of management plans, which are fundamental instruments in the implementation of conservation measures. This study explores the viability of using existing forest plans to assist in this purpose. As case study, we consider the regulatory framework of the Veneto Region, northern Italy. We collected quantitative and qualitative data on forest plans at the regional and at three sub-regional spatial scales: local, district, and biogeographical. Forest plans cover about 54% of the terrestrial area of Natura 2000 sites in Veneto, and 75% of Sites of Community Importance in the Alpine biogeographical region. At the local scale of analysis, metrics from forest plans represent a valuable historical record which can be used to interpret the current state and future trends, especially for forests with long management records. These data can be used to assess biodiversity indicators for the monitoring of Natura 2000 forest and non-forest habitats, in compliance with Article 17 of the Habitats Directive. Moreover, the heterogeneous stand conditions which are promoted by some forest management approaches can improve the conservation efforts for some habitats and species. The scale of local forest plans are typically the most appropriate for implementing habitat management strategies. From this study, we conclude that management authorities should take advantage of the wide spatial coverage and distribution of existing forest plans, especially in mountain areas inside and outside the Natura 2000 network, for the successful conservation of European Union habitats and species

Larch Status A

LARCH is a model that is used by the Netherlands Environmental Assessment Agency (PBL) for ex-ante and ex-post evaluations of Dutch nature policies. LARCH generates the potential habitat networks of a species. LARCH will not predict the actual distribution of a specie

Retrospective Analysis of Wood Anatomical Traits Reveals a Recent Extension in Tree Cambial Activity in Two High-Elevation Conifers

The study of xylogenesis or wood formation is a powerful, yet labor intensive monitoring approach to investigate intra-annual tree growth responses to environmental factors. However, it seldom covers more than a few growing seasons, so is in contrast to the much longer lifespan of woody plants and the time scale of many environmental processes. Here we applied a novel retrospective approach to test the long-term (1926–2012) consistency in the timing of onset and ending of cambial activity, and in the maximum cambial cell division rate in two conifer species, European larch and Norway spruce at high-elevation in the Alps. We correlated daily temperature with time series of cell number and lumen area partitioned into intra-annual sectors. For both species, we found a good correspondence (1–10 days offset) between the periods when anatomical traits had significant correlations with temperature in recent decades (1969–2012) and available xylogenesis data (1996–2005), previously collected at the same site. Yet, results for the 1926–1968 period indicate a later onset and earlier ending of the cambial activity by 6–30 days. Conversely, the peak in the correlation between annual cell number and temperature, which should correspond to the peak in secondary growth rate, was quite stable over time, with just a minor advance of 4–5 days in the recent decades. Our analyses on time series of wood anatomical traits proved useful to infer on past long-term changes in xylogenetic phases. Combined with intensive continuous monitoring, our approach will improve the understanding of tree responses to climate variability in both the short- and long-term context

Chemical composition of the humus layer, mineral soil and soil solution of 150 forest stands in the Netherlands in 1990

A nationwide assessment of the chemical composition of the humus layer, mineral topsoil (0-30 cm) and soil solution in both topsoil and subsoil (60-100 cm) was made for 150 forest stands in the year 1990. The stands, which were part of the national forest inventory on vitality, included seven tree species and were all located on non-calcareous sandy soils. Results show increased levels of nitrogen, aluminium, lead and cadmium in at least one of the various soil compartments, indicating the occurrenceof eutrophication, acidification and heavy-metal pollution. Tree species and stand characteristics, such as tree height and canopy coverage, appear to have the largest effect on the concentration level of the various chemical parameters by influencing the input by atmospheric deposition. The various assessments allowed the calculation of various parameters related to aluminium dissolution, cation exchange and phosphate adsorption, to be used in simulation models

Additive model of Larix sp. forest stand biomass sensitive to temperature and precipitation variables in Eurasia

The first attempt of modeling changes in additive component composition of biomass of Larix sp. communities on the Trans-Eurasian hydrothermal gradients based on regional peculiarities of age and morphology of the forests is attempted. The increase of all biomass components of the tree layer with increasing temperature at the constant precipitation and its decrease with increasing precipitation at the constant temperature is established. The positive relationship of the understory biomass with the temperature in the areas of insufficient moisture as the transition to moisture-rich areas is replaced by the opposite one. The development of such models for basic forest-forming species in Eurasia will give possibility to predict any changes in the biological productivity of forest cover of Eurasia in relation to climate change. © 2019 IOP Publishing Ltd. All rights reserved

A comparison of statistical models for short categorical or ordinal time series with applications in ecology

We study two statistical models for short-length categorical (or ordinal) time series. The first one is a regression model based on generalized linear model. The second one is a parametrized Markovian model, particularizing the discrete autoregressive model to the case of categorical data. These models are used to analyze two data-sets: annual larch cone production and weekly planktonic abundance.Comment: 18 page

Chemical composition of the humus layer, mineral soil and soil solution of 200 forest stands in the Netherlands in 1995

A nationwide assessment of the chemical composition of the soil solid phase and the soil solution in the humus layer and two mineral layers (0-10 cm and 10-30 cm) was made for 200 forest stands in the year 1995. The stands were part of the national forest inventory on vitality, included seven tree species and were all located on non-calcareous sandy soils. The soils are nearly all characterized by high nitrogen and metal contents in the humus layer ans low pH and base saturation values in the minerallayer, indicating the occurrence of eutrophication, acidification and heavy metal pollution. Of those stands, 124 were also sampled and analysed in 1990. Compared with 1990, results for the humus layer show a decrease (release) in nitrogen and metal contents and pools, and a decrease in total and exchangeable pools of base cations, combined with increase in hydrogen saturation. This indicates a decrease in eutrophication but an ongoing acidification. The soil solution, however, shows a decrease in Al/Caand NH4/K ratios, implying a slight recovery from acidification. For the mineral soil, the changes in element pools are too unreliable to draw any distinct conclusion