REPORT OF THE PLANNING COMMITTEE FOR THE NORTHEAST EXTENSION SEMINAR ON PUBLIC ISSUES INVOLVING LAND

Land Economics/Use,

PUBLIC AND PRIVATE PROPERTY RIGHTS

Land Economics/Use,

Different investment treaties, different effects

Until recently, quantitative assessments of International Investment Agreements (IIAs) have tended to treat them as interchangeable. Such assessments assume that the only measure of investor protections encoded in IIAs is whether a treaty had been signed and/or entered into force. However, the actual investment effects of investment treaties depend greatly on context

Evaluation of Economic Injury Level, Biological Control, and Host Plant Resistance for Soybean Aphid in NY

Objectives: 1. Evaluate soybean yield loss at different aphid densities in a field cage experiment and in field surveys in order to define an economic injury level (EIL) for New York. 2. Conduct a survey of soybean variety trials to determine relative abundance and yield impacts of soybean aphid, Aphis glycines Matsumura on commonly grown soybean varieties in New York. Soybean rust, Phakopsora pachyrhizi , will also be surveyed for detection. 3. Survey natural enemies (predators, parasitoids and fungal pathogens) affecting soybean aphid in New York State. Evaluate the importance of these natural enemies (especially fungal epizootics) for controlling soybean aphids while soybean plants grow and soybeans develop. 4. Enhance cooperative extension outreach efforts, communication, networking, regarding soybean aphid, optimize rapid and early detection of this exotic pest: Continue to increase awareness of soybean aphid and its importance to NY field personnel (producers, crop consultants, agricultural industry, field crop extension educators). Utilize electronic technology and traditional approaches to strengthen timely communication and convey survey activities and findings to Northeast region clientele, and other stakeholders. 5. Share survey findings with appropriate soybean IPM workers in the Northeast and north central US (Northeast IPM and NC 502), state and federal agencies (USDA National Agricultural Pest Information System (NAPIS), USDA Cooperative Agricultural Pest Survey (CAPS), and USDA Animal Plant Health Inspection Service (APHIS))

Interrelationships Among Airports And The Hinterland Players. A Value Network Analysis Approach

The measure of an airport performance and its efficiency is generally made using operational and financial data, thus providing a position rank in respect to a set of airports. But this methodology, by itself, cannot provide the true relationships between a certain position in the rank of an airport and the generated value associated with that position, either within the entire business system of the airport or within the inter-relationships that it establishes with the surrounding community. To understand the role that airport infrastructure plays within the regional development, not only a variety of relationships must be recognized, but also how they create or may create value. For better understanding of how processes and people create value in an airport network ecosystem, it is possible to use Value Network Analysis (VNA). VNA is a methodology that provides a capability to understand, visualize and optimize internal and external value networks of complex economic ecosystems, thus capturing dynamics of the entire system. This paper presents a map of the interrelationships between the airport's players and the hinterland's players in three different scenarios, the air traveler, the supply chain, and the infrastructure development, considering the related impacts in the form of the tertiary effects and the perpetual effects. The first scenario results from the existence of the air transport services for the use of individuals. The second is related with the airport suppliers and the services supplies to the air passenger and cargo when companies need a high speed and quality transport services. The third scenario considers perpetual effects associated with the regional economy considering that an infrastructure investment will raise the level of activity and stimulates productivity. These scenarios are comprised in a adapted model with four interconnected interface domains that we assume reinforce the sustainability of airport business activities within a territory in the long-term: Economic Development, Land Use, Infrastructures and Governance. This model is essentially an organizing tool that identifies key policy areas to improve integrated decision-making processes and is a conceptual framework for future research. The application of VNA methodology allows the recognition and assessment of impacts and relationships between multiple systems, thus avoiding an ad-hoc analysis and compartmentalized of issues. In the context of the present study not only a variety of relationships are recognized, but also how they create or may create value, allowing a better understanding of the role that airport infrastructure plays within the regional development

Ecological classification of southern intertidal zones of Qeshm Island, based on CMECS model

The “Coastal and Marine Ecological Classification Standard (CMECS)”, a new approach to ecological classification, was applied to 122 km of the southern intertidal zone of Qeshm Island located the Hormouz Strait - the Persian Gulf. Two components of this model, Surface Geology (SGC) and Biotic Cover (BCC) were used. Considering the extent and geomorphological alternations of the covered area, 12 sampling sites within 5 sub-regions were designated using by GPS. In total, 60 habitats (biotopes) with 47 codes were determined; this variety of biotopes is directly related to the diverse surface geology (substrate) of the covered area. Most of the biotopes and codes were recorded in the mid-eastern coastal zone, due to heterogeneity in substrate structure associated with numerous ecological niches in rocky shores. Crustacean species such as Eriphia smithi, Thalamita prymna, Molluscan species such as Clypeomorous bifisciatus, Cerithium caeruleum and echinoderm species such as Echinometra mathaei and Ophiactis sp. were characteristic of rocky shores, while Crustacea groups including Ocypode rotundata and Dotilla sp., and Umbonium vestiarium (Mollusca) were characteristic of sandy shores. Although the highest number of codes was recorded in Zeitun Park site (Eastern coast), it did not possess the expected specific species (such as Diadema setosum, Linckia multiflora and Ophiocoma scolopendrina), that were encountered in sites with similar surface geology. This could have been caused by tourist traffic at the Zeitun Park site

Cannibalism as a life boat mechanism

Under certain conditions a cannibalistic population can survive when food for the adults is too scarce to support a non-cannibalistic population. Cannibalism can have this lifeboat effect if (i) the juveniles feed on a resource inaccessible to the adults; and (ii) the adults are cannibalistic and thus incorporate indirectly the inaccessible resource. Using a simple model we conclude that the mechanism works when, at low population densities, the average yield, in terms of new offspring, due to the energy provided by one cannibalized juvenile is larger than one

Density-Dependence as a Size-Independent Regulatory Mechanism

The growth function of populations is central in biomathematics. The main dogma is the existence of density dependence mechanisms, which can be modelled with distinct functional forms that depend on the size of the population. One important class of regulatory functions is the $\theta$-logistic, which generalises the logistic equation. Using this model as a motivation, this paper introduces a simple dynamical reformulation that generalises many growth functions. The reformulation consists of two equations, one for population size, and one for the growth rate. Furthermore, the model shows that although population is density-dependent, the dynamics of the growth rate does not depend either on population size, nor on the carrying capacity. Actually, the growth equation is uncoupled from the population size equation, and the model has only two parameters, a Malthusian parameter $\rho$ and a competition coefficient $\theta$. Distinct sign combinations of these parameters reproduce not only the family of $\theta$-logistics, but also the van Bertalanffy, Gompertz and Potential Growth equations, among other possibilities. It is also shown that, except for two critical points, there is a general size-scaling relation that includes those appearing in the most important allometric theories, including the recently proposed Metabolic Theory of Ecology. With this model, several issues of general interest are discussed such as the growth of animal population, extinctions, cell growth and allometry, and the effect of environment over a population.Comment: 41 Pages, 5 figures Submitted to JT

Gene surfing

Spatially resolved genetic data is increasingly used to reconstruct the migrational history of species. To assist such inference, we study, by means of simulations and analytical methods, the dynamics of neutral gene frequencies in a population undergoing a continual range expansion in one dimension. During such a colonization period, lineages can fix at the wave front by means of a ``surfing'' mechanism [Edmonds C.A., Lillie A.S. & Cavalli-Sforza L.L. (2004) Proc Natl Acad Sci USA 101: 975-979]. We quantify this phenomenon in terms of (i) the spatial distribution of lineages that reach fixation and, closely related, (ii) the continual loss of genetic diversity (heterozygosity) at the wave front, characterizing the approach to fixation. Our simulations show that an effective population size can be assigned to the wave that controls the (observable) gradient in heterozygosity left behind the colonization process. This effective population size is markedly higher in pushed waves than in pulled waves, and increases only sub-linearly with deme size. To explain these and other findings, we develop a versatile analytical approach, based on the physics of reaction-diffusion systems, that yields simple predictions for any deterministic population dynamics