Stand structure and development after selective logging with systematically aligned skid trails, directional felling and climber cutting in a dipterocarp rainforest in Sabah, Malaysia

The tropical rainforests around the world are extremely diverse and support a huge number of timber tree species and have therefore been severely logged. One area that has produced, and still produces, large amounts of timber is Southeast Asia. In this region the most commercially important timber trees belong to the family dipterocarpacae, (dipterocarps). Logging is mostly carried out relatively unplanned and causes therefore great damage to the residual stand. Better planned logging and silvicultural activities, using (for instance) planned skid trails, directional felling and climber-cutting, should reduce the damage and create healthier residual stands. This study tested a logging method involving systematically aligned skid trails combined with directional felling, called supervised logging (SL) and compared it to the conventional logging (CL) practiced in the area. Both logging methods were combined with (CC) and without (NCC) climber cutting. All trees exceeding 10 cm in diameter at breast height (dbh), and a random selection of seedlings and saplings were measured before logging (1992) and for a period of eight years after logging (1993-2001). More trees tended (0.050 < P ≤ 0.100) to be logged where CL was applied than in SL plots (the mean numbers of all stems and dipterocarps logged per ha were 13.0 and 12.4, respectively, in CL plots, compared to 9.4 and 6.7 in SL plots). The skid trail network applied in SL resulted in disturbance to around 7 % of the soil cover. The corresponding figure for the unplanned skid trail network in CL was higher (ca. 10 %), but not significantly different. Climber cutting resulted in four more dipterocarp trees being logged ha-1, compared with NCC: a statistically significant difference (P ≤ 0.050). Basal area lost or severely damaged differed between methods for some diameter classes with mainly CL leading to greater losses. The residual stand contained statistically significantly more dipterocarp seedlings after CL than after SL, while saplings and trees showed the opposite trend, i.e. more individuals were left in the residual stand after SL than after CL. There were significantly (ca. 30%) more 10-29 cm dbh dipterocarp trees in the residual stand after SL than after CL. Cutting climbers had no initial effect on the residual stand in terms of densities of seedlings, saplings trees of either all species or dipterocarps. Data collected during the subsequent period show inter alia, that the net basal area increased at similar rates following both logging methods, considering all species. There was also no significant difference between SL and CL in terms of dipterocarp net basal area, although this parameter grew by 1.0 m2 ha-1 after SL and declined by 0.1 m2 ha-1 after CL. Climber cutting significantly and positively affected net basal area growth, which amounted to 6.4 m2 ha-1 and 3.3 m2 ha-1 in the CC and NCC plots, respectively. The substantially higher growth associated with CC was mainly due to the growth and recruitment of small trees, mainly pioneer species

Politics and preferences

The overall aim of this thesis is to better understand how politics and preferences influence policy outcomes. The thesis consists of two papers that examine two different policy outcomes in Swedish municipalities. Paper I analyzes the effect of income and education on the environmental policy performance of Swedish local governments. In estimating the effects of income and education we will also examine how they interact with political participation. To examine this I use panel data based on an environmental ranking of Swedish municipalities made every year between 1993 and 2001. The empirical results show that there is a positive relationship between income and the environmental policy performance. This relationship is however captured by controlling for the education level, which has a positive relationship with the environmental policy performance. Controlling for municipal fixed effects and relevant control variables does not change this result. Furthermore we find that political participation has significant interaction effects with both income and education. Paper II develops a regression discontinuity (RD) design to estimate the causal effect of political party power on the placement of refugee immigrants in Swedish municipalities. That Swedish municipalities have a proportional election system puts forward specific challenges for using a RD design, which this paper will provide solutions to. The identification strategy is based on the idea that a specific party getting one more seat or not in the municipal council can be considered as good as random if the party is close to a seat change. Even though this paper only looks at Swedish data the method could be applied to other countries with proportional election systems. The results of the paper show that the political party power has a large effect on the placement of refugee immigrants in Swedish municipalities

Population management of cone and seed insects in spruce seed orchards

Seed orchards have been established in order to produce high quality seeds for reforestation and forestation. However, seed production in spruce (Picea abies (L.) Karst.) seed orchards is severely hampered by cone- and seed-feeding insects. Therefore it is of great importance to find methods to reduce damages from insects. This thesis summarizes and discusses results presented in four papers concerning various methods and chemicals (insecticides and a pheromone) for damage reductions in spruce seed orchards. Area-wide application of the biological insecticide Turex 50 WP was shown to reduce damage by two of the four most serious pest species. Concerns were then raised that feeding by insects that are not affected by this insecticide may increase following its application, in response to the consequent increases in the availability of food and space, resulting in little no or difference in overall damage. A follow up study indicated that there would probably not be any problem with increased feeding by the larvae survived and that spraying of an insecticide not affecting all species would probably be cost effective. However, various species-related and abiotic factors (e.g. rain and temperature) affect the efficacy of insecticide treatments, both among and within years, and thus should be taken into account. A system that would be less sensitive to weather and also may affect all pest species and at the same time avoid affecting the surrounding environment is injectable systemic insecticides. In order to increase the cost efficiency a study was performed where insecticide was combined with the flower stimulating hormone gibberellin and successfully reduced damages and increased number of flowers. In order to know if and when an insecticide application should be carried out, pheromone for trapping insects is a useful tool. But in order to do so there must be a pheromone available. During the spring of 2009 a pheromone for C. strobilella was identified and synthesized. The study showed that the amount of pheromone released from the female was extremely low, 1 pg, so the male antenna is supersensitive in order to find females. This implies also that this species can be a good candidate for mating disruption

Autopoiesis Concepts for Chemical Origins of Life and Synthetic Biology [Stenogram of the popular lecture on the foreign bibliographic seminar]

The monograph (Luisi P.L. "The Emergence of Life: From Chemical Origins to Synthetic Biology", 2010, Cambridge University Press, Cambridge, New York etc., 315 p.) is a well-written, informative book providing a novel view on the interrelation between the abiogenesis as the natural origin of life and synthetic biology as the artificial synthesis of life. This concept is specially known as autopoiesis. As its name implies, it is a correlate of self-organization, but this word has quite a broad meaning in the literature. Consequently, some further restriction is required for this term in abiogenetic, as well as in "biogenetic" applications. There is, in fact, one basic reason for considering the abiogenetic problem in terms of self-organization theory. It follows from the extremely boundless complexity of biological systems

REXUS 2 - The first Eurolaunch Project

Sounding rocket and balloon launches have been conducted since more than 30 years at Swedish Space Corporation (SSC), ESRANGE. MORABA, the Mobile Rocket Base of the German Aerospace Center (DLR), has planned and performed sounding rocket and balloon launches throughout the world since the late sixties. With the creation of EuroLaunch, the long-lasting co-operation of the two complementary technical centres ESRANGE and MORABA is being enhanced and intensified. The REXUS 2 student rocket was the first project to be designed, built and launched under the EuroLaunch cooperation. A driving force in research by means of sounding rockets, has been the German Aerospace Center, which through its Mobile Rocket Base team, has conducted launches and operations all over the world. The Swedish Space Corporation and the German Aerospace Center have now entered into a deeper relationship by establishing a joint co-operation called EuroLaunch. On December 8th, 2003, a co-operation agreement was signed at ESRANGE. The agreement will strengthen the long-lasting and ongoing relationship between SSC and DLR within the area of sub-orbital services for upper atmosphere and microgravity research as well as future fields of research interest. EuroLaunch is currently involved in several projects which aim at strengthening the co-operation and also providing new possibilities to the scientific communities. The first EuroLaunch project was the REXUS 2 student rocket, which was successfully launched on October 28th, 2004 at ESRANGE. Within the REXUS 2 project the flexible work sharing of EuroLaunch has been put to its first test, as personnel from the two organisations have supported each other during heavy workload periods

Building need-based systems for complex hostile situations

The concept of need-based systems is that they are not instantiated until they are brought to use. Such systems are either designed, assembled and instantiated for very concrete needs, alternatively built on speculation. They are used for evaluation, training or for real. In most cases they are not instantiated, though possibly brought into use as needed. How should needs be expressed? Needs are expressed in terms of results and effects. They may be simple or complex, where complex needs can be seen as structured compositions of more basic needs. When facing a hostile situation, it is critical to have predicted all needs necessary for resolving the given assignment. The complexity of needs, and of their interdependencies may appear to be overwhelming, and it is important to find optimal solutions to the problem at hand. What is needed is a knowledge-based conceptual model that describes the inter-relation of needs, predictions and effects. This paper proposes a number of viewpoints and tools to be applied to the construction of need-based systems -- viewing needs as a resource economy, as a non-linear dynamical system, making use of game theory, decision theory, and risk management. Models for needs and predictions, and the ways they are utilized, extends current systems engineering methods

Gibbs properties of the fuzzy Potts model on trees and in mean field

We study Gibbs properties of the fuzzy Potts model in the mean field case (i.e on a complete graph) and on trees. For the mean field case, a complete characterization of the set of temperatures for which non-Gibbsianness happens is given. The results for trees are somewhat less explicit, but we do show for general trees that non-Gibbsianness of the fuzzy Potts model happens exactly for those temperatures where the underlying Potts model has multiple Gibbs measures

Uniqueness and non-uniqueness in percolation theory

This paper is an up-to-date introduction to the problem of uniqueness versus non-uniqueness of infinite clusters for percolation on ${\mathbb{Z}}^d$ and, more generally, on transitive graphs. For iid percolation on ${\mathbb{Z}}^d$, uniqueness of the infinite cluster is a classical result, while on certain other transitive graphs uniqueness may fail. Key properties of the graphs in this context turn out to be amenability and nonamenability. The same problem is considered for certain dependent percolation models -- most prominently the Fortuin--Kasteleyn random-cluster model -- and in situations where the standard connectivity notion is replaced by entanglement or rigidity. So-called simultaneous uniqueness in couplings of percolation processes is also considered. Some of the main results are proved in detail, while for others the proofs are merely sketched, and for yet others they are omitted. Several open problems are discussed.Comment: Published at http://dx.doi.org/10.1214/154957806000000096 in the Probability Surveys (http://www.i-journals.org/ps/) by the Institute of Mathematical Statistics (http://www.imstat.org