Energy and Water Related Parameters in Tomato and Cucumber Greenhouse Crops in Semiarid Mediterranean Regions. A Review, Part II: Irrigation and Fertigation

Increasing agricultural systems’ resource efficiency is the key action for producing adequate food quantities in semi-arid Mediterranean regions while coping with water scarcity, environmental constraints and economic issues. Optimisation of irrigation and fertigation practices imposes different approaches, considering plant-water-soil relationships based on prevailing greenhouse microclimatic conditions, ensuring optimal production per drop of water and unit of fertiliser. In the content of "precision agricultural farming systems", nutrient uptake modelling, phyto-sensing, smart and sustainable technologies must be applied for monitoring and evaluating water and nutrients crops supply. However, in many cases, the use of irrigation and fertigation recipes given in the literature may not be compatible in the Mediterranean, as they usually originated based on northern European climatic conditions. The objective of this work is an attempt to understand various aspects of irrigation and fertigation management in vegetable fruiting crops such as tomato and cucumber towards nutrients and water resource sustainability in Mediterranean greenhouses.

Assessment of Postharvest Losses Due to Catching Undersized Fishery Commodities and Size-Dependent Pricing in the Philippines

The continuing decline in catch rates instigates various fishing adjustments to keep up with the demands of a growing population. Fishery resources are being caught before they can attain their optimum harvestable size. Undersized catch elicits lower economic value; thus, considered as losses in postharvest fisheries. The present study focused on generating actual data on the volume of undersized catches in selected landing sites in the Philippines. It aims to quantify the magnitude of postharvest and financial losses incurred from catching fishery commodities below their marketable sizes. The estimated loss at 0.97% and 4.02% for capture and aquaculture commodities, respectively, was equivalent to PHP 15,235,290 financial loss. Estimation of losses by commodity showed that squid recorded the highest at 20.14%, followed by tilapia (9.61%), blue swimming crab (4.48%), shrimp (2.75%), small pelagics (1.98%), mussel (1.46%), oceanic tuna (0.91%), by-catch (0.79%), milkfish (0.09%), and oyster (0.02%). Excessive catching of undersized BSC and squid in Western Visayas may lead to overexploitation of resources and may adversely affect subsequent recruitment in the long run. The study's results indicate that catching undersized species could lead to substantial postharvest losses and subsequent loss of potential revenue to the industry players. Allowing the stocks to attain their maximum biomass level will minimize postharvest losses; thus, maximizing utilization of resources and benefits derived from the sector. Unrestrained catching of undersized fishery commodities undermines resource sustainability, economic potential, and food security. The strengthening of regulatory frameworks is, therefore, necessary to address both economic and ecological impacts.

Trade and Resource Sustainability with Asset Markets

Trade changes incentives to protect an open-access natural resource independently of its effect on the resource price. General equilibrium linkages cause resource policy to affect the price of privately owned assets regardless of whether they are used in the resource sector. In the closed economy, the asset market in our overlapping generations setting creates incentives for currently living agents to protect the natural resource. The interplay of the asset market and general equilibrium effects causes trade to reverse these incentives. Trade liberalization and the establishment of formal property rights are policy complements: the former makes the latter more important.

The Seaweed Information System (SIRULA): A Preliminary Concept and Integrated Design

Seaweed is one of the fisheries commodities, which has been proven to improve the household income of coastal and small island communities in Indonesia for the last two decades. The global need for seaweed is rising, since it is used as a raw material for many industries, i.e.: food, pharmaceuticals, cosmetics, livestock feed, and fertilizers. These factors have encouraged the Government of Indonesia to increase the quantity and quality of seaweed commodities until it reaches a strategic position in the fisheries sector. One of the efforts in enhancing the data and information reliability, which will support all business actors from upstream to downstream; to accelerate the industrialization and production, resource sustainability, and improving the welfare of coastal and small island communities. This paper aims to provide an overview of the concept and design of seaweed information systems, based on the principles of traceability, sustainability, production process improvement, and system integration. It is expected that business actors, resources managers, and policymakers will take advantage of information system, where reliable data and information can be accessed easily in real-time.

New approaches to value creation in the tourism sector - the circular economy

"ABSTRACT. The circular economy is an alternative economic model to the current linear economy. The main feature of the circular economy is to preserve the value of resources. The circular economy generates indisputable environmental benefits, social benefits and added value for companies, aspects necessary to guarantee resource sustainability and ecological diversity in a globalized, complex and often unpredictable global context. Despite the fact that tourism plays an important role in the economic development of tourist regions and in the integration of these economies in the process of globalization, it puts great pressure on natural resources and the environment. Tourism activity generates environmental impacts and economic impacts. The aim of this paper is to analyze the future tendencies of tourism, how the circular economy can create value for the tourism sector and the steps to be followed to create a sustainable model. The society we live in has exhausted the resources needed to meet the future needs of an increasingly affected planet. Tourism is a sector sensitive environmentally, because while exploiting resources for its economic development, compromising their future growth. For this reason, it is very important to adopt tourism practices that promote respect for the planet - Earth, because we destroy our home and today we are already living the consequences and the circular economy is born of the real need to save the planet we live on. Change is the key to a sustainable model. Today there are endless opportunities, we need to rethink our current system and open up to new perspectives through innovation and creativity. Keywords: Circular economy, Sustainable tourism, Resources, Tourism JEL classification: Z32, L83, Q01, Q56 "

MATHEMATICAL MODELS AND METHODS FOR ASSESSING AND MANAGING RESOURCE SUSTAINABILITY OF ENTERPRISE DEVELOPMENT

В статье предложены математические модели и методы получения комплексной оценки ресурсной устойчивости и достижения определенных показателей развития за счет применения интенсивных технологий использования ресурсов предприятия. This article proposes mathematical models and methods for obtaining a comprehensive assessment of resource sustainability and achieving certain development indicators through the use of intensive technologies for the use of enterprise resources.

Long-Term Conservation Effects of Protected Areas in Stochastic Population Dynamics

Terrestrial and marine protected areas are essential tools in mitigating anthropogenic impacts and promoting population persistence and resource sustainability. Adequately implemented protected areas (PAs) aim to promote conservation by increasing population size and reducing its variability. To resolve how these effects depend on PA features, I develop and analyze new models of stochastic processes that encompass the fluctuations generated by demographic or environmental stochasticity in PAs management. The stochastic model is built upon individual processes. In the model, density-independent mortality, migration between PAs and non-PAs, organism preference for PAs, and size characterize the features of the PA. The effect of PAs size is also examined. The long-term conservation effects are quantified using the coefficient of variation (CV) of population size in PAs, where a lower CV indicates higher robustness in stochastic variations. The results from this study demonstrate that sufficiently reduced density-independent mortality in PAs and high site preference for PAs and immigration rate into PAs are likely to decrease the CV. However, different types of stochasticity induce rather different consequences: under demographic stochasticity, the CV is always reduced because PAs increase the population size therein, but an increased population size by PAs does not always decrease the CV under environmental stochasticity. The deterministic dynamics of the model are investigated, facilitating effective management decisions.