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Para poder realizar una toma de decisiones política acertada y realizar una gestión apropiada de los ecosistemas forestales, es necesario contar con una información robusta, conocer las tendencias actuales y ser capaces de evaluar las consecuencias de las diferentes actuaciones posibles. Los Inventarios Forestales Nacionales (IFN) son las mayores fuentes de información forestal a nivel nacional y suponen un pilar fundamental para establecer políticas forestales. Para satisfacer las demandas de información, tanto nacionales como internacionales, cada país ha diseñado su IFN con una metodología propia considerando las características particulares de sus masas forestales. En este artículo se describe la metodología y orientación del IFN español a lo largo de los diferentes ciclos en los que se ha llevado a cabo. Además, se explica cómo da respuesta a los diferentes requerimientos de información internacionales y se señalan las necesidades de armonización con otros inventarios forestales nacionales para que sus indicadores sean comparables. Finalmente, se detallan los retos que afronta y la orientación de sus líneas futuras, como son el establecimiento de bases de datos abiertas y la ampliación de la toma de datos para obtener un inventario multi-objetivo que pueda responder a todos los requerimientos de información existentes.

La restauración ecológica de espacios afectados por minería a cielo abierto debe tener como objetivo reconstruir los ecosistemas naturales del entorno. En ambientes forestales, la presencia de especies leñosas proporciona el grado de integración y funcionalidad de las zonas en fase de recuperación, pero la presión social puede determinar que estas expectativas se limiten a obtener cubiertas de herbáceas para obtener una incorporación visual, "verde", rápida. El uso de enmiendas orgánicas y riego puede contribuir a acelerar el establecimiento de esta cubierta. Sin embargo, los proyectos de restauración deben considerar técnicas a corto plazo que compatibilicen la estabilización del substrato con la recuperación de las comunidades vegetales de referencia. Una cubierta herbácea densa, podría comprometer el establecimiento de componentes clave de los ecosistemas de referencia. En este documento presentamos los resultados de la evaluación del efecto de la aplicación de compost y riego sobre la tasa de erosión, la cobertura vegetal y la respuesta de brinzales de especies leñosas en una cantera de caliza situada en el Macizo del Garraf (Barcelona, España). La presencia de cubiertas herbáceas integró visualmente las áreas rápidamente y tuvo un efecto positivo sobre el control de la erosión superficial, aunque su composición y estructura fueron muy distintas a las de su entorno natural. La adición de compost y el riego incrementaron la cubierta herbácea. Al margen de Pinus halepensis, las especies leñosas plantadas presentaron una supervivencia del 50-60%. Dos especies, Rhamnus alaternus y Rosmarinus officinalis se vieron negativamente afectadas por la cubierta herbácea. A partir de los resultados obtenidos, discutimos el efecto de la introducción de leñosas sobre la diversidad y su papel como núcleos de dispersión y posterior expansión.

El objetivo de este trabajo fue evaluar el efecto de la asociación de Leucaena leucocephala, y su co-inoculación con una cepa del hongo micorrízico arbuscular (HMA) Claroideoglomus claroideum y un aislado local de rizobio, sobre el comportamiento de las gramíneas asociadas (Bouteloua gracilis, Bouteloua curtipendula y Setaria macrostachya). Se estudiaron las estructuras micorrízicas y la nodulación. Se realizaron tres experimentos independientes, uno por cada gramínea, en asociación con L. leucocephala co-inoculada y sin inocular, o sola (como testigo). Los pastos asociados con L. leucocephala co-inoculada produjeron mayor cantidad de tallos que aquellos asociados con L. leucocephala sin inocular. B. gracilis y B. curtipendula acumularon mayor biomasa cuando se asoció con L. leucocephala co-inoculada. Las concentraciones de clorofilas a, b y totales en S. macrostachya y la de clorofila b en B. gracilis se vieron favorecidas por la asociación con L. leucocephala. La co-inoculación promovió el desarrollo de estructuras micorrízicas en la rizósfera y el número de nódulos en raíces de L. leucocephala, aunque el porcentaje de nódulos efectivos no reflejó diferencias entre tratamientos. En conclusión, la asociación de gramíneas con L. leucocephala y su inoculación con HMA y aislados de rizobios locales no solo promueve el desarrollo de estructuras micorrízicas y la nodulación, sino también aumenta el crecimiento y el contenido de pigmentos fotosintéticos en las gramíneas asociadas

Seven coals from the Carbonera Formation and six from the Los Cuervos Fm., in the Casigua - El Cubo area, the State of Zulia, Venezuela, have been characterized according to physical (HGI hardness), rheological (FSI, plastometry, dilatometry) and chemical parameters (proximate and ultimate analysis, sulfur forms, major elements in ashes). The samples from Carbonera, c1assified as sapropelic coals because of their high hardness and calorific value, together with their position in the van Krevelen diagram, possess a low rank (high percentage of volatile matter and high H/C atomic ratio) and poor rheological properties (FSI= 1.0). These characteristics make the Carbonera Fm. coals apt as a source of synthetic fuels, chemicals and as a stoker. The samples from the Los Cuervos Fm., classified as high-volatile bituminous type A coal (ASTM D 388), present properties (low moisture, ash and sulfur content average heating value of 14940 BTU/lb (m.a.f.), low fouling and slagging indexes) similar to those of Guasare, and can be used as high-quality thermal coals. Their rheological properties (Gieseler fluidity and Audibert-Arnu dilatometry) limit their application in the coke industry to that of a minority component in blends with other, strongly coking coals.

Análisis del carbono en los suelos agrícolas de España. Aspectos relevantes en relación a la reconversión a la agricultura ecológica en el ámbito mediterráneo. Los niveles de carbono orgánico en suelos agrícolas son especialmente relevantes en los modelos de gestión que se basan en la reserva orgánica de nutrientes. La disminución de materia orgánica que ocurre en los suelos roturados puede en algunos casos determinar la degradación del suelo. Este hecho puede ser especialmente relevante en condiciones climáticas límite (secas y semiáridas). A partir del análisis de una base de datos de suelos españoles se discute la distribución del C en el horizonte superficial de suelo según el clima y según el uso. Para cada área climática, mediante comparación entre suelos forestales y agrícolas se observa que los suelos de clima semiárido presentan una mayor resistencia a la pérdida de C y una menor resiliencia que los suelos de climas más húmedos. Este hecho nos hace pensar que los suelos semiáridos pueden estar cerca de los umbrales de degradación y que por lo tanto su gestión debería evitar les pérdidas de materia orgánica.

The objective of this work was to evaluate the effect of the simple and combined inoculation with three local rhizobia isolates (R1, R2 and R3) and two species of arbuscular mycorrhizal fungi (Glomus cubense -AMF1- and Claroideoglomus claroideum -AMF2-) on mycorrhizal colonization, nodulation, growth and biomass production of Leucaena leucocephala in a substrate with a close to neutrality pH under greenhouse conditions. Thirteen treatments were evaluated in a completely randomized design with five replications. The inoculation and co-inoculation promoted greater plant growth with respect to the control without inoculation and to the fertilization treatment. Within the inoculation and co-inoculation treatments, one rhizobium isolate (R2) stood out for producing the highest plant height and leaflet production, while the R3 + AMF1 and R3 + AMF2 combinations promoted the highest plant height, and also promoted higher biomass together with R1 + AMF1. In addition, the R3 + AMF2 combination stood out for presenting a high number of AMF spores, frequency and intensity by AMF colonization, and nodule activity. It is concluded that inoculation with local rhizobia isolates and their combination with AMF favors the development of mycorrhizal structures, nodulation, growth and biomass production of L. leucocephala grown in a substrate with neutral pH. Isolate R2 and the combination R3 + AMF2 were identified as effective inoculants to increase plant growth.

One of the most challenging issues in Mediterranean ecosystems to date has been to understand the emergence of discontinuous changes or catastrophic shifts. In the era of the 2030 Sustainable Development Goals, which encompass ideas around Land Degradation Neutrality, advancing this understanding has become even more critical and urgent. The aim of this paper is to synthesize insights into the drivers, processes and management of catastrophic shifts to highlight ways forward for the management of Mediterranean ecosystems. We use a multidisciplinary approach that extends beyond the typical single site, single scale, single approach studies in the current literature. We link applied and theoretical ecology at multiple scales with analyses and modeling of human–environment–climate relations and stakeholder engagement in six field sites in Mediterranean ecosystems to address three key questions: i)How do major degradation drivers affect ecosystem functioning and services in Mediterranean ecosystems?ii)What processes happen in the soil and vegetation during a catastrophic shift?iii)How can management of vulnerable ecosystems be optimized using these findings?Drawing together the findings from the use of different approaches allows us to address the whole pipeline of changes from drivers through to action. We highlight ways to assess ecosystem vulnerability that can help to prevent ecosystem shifts to undesirable states; identify cost-effective management measures that align with the vision and plans of land users; and evaluate the timing of these measures to enable optimization of their application before thresholds are reached. Such a multidisciplinary approach enables improved identification of early warning signals for discontinuous changes informing more timely and cost-effective management, allowing anticipation of, adaptation to, or even prevention of, undesirable catastrophic ecosystem shifts.

Petrol engine with strautified charge has compression ratio 12-14 and air/fuel ratio 3 and more without detonation. Charge strautification increases part-load efficiency by 10-15%. Automotive diesel without supercharging has 50% smaller specific output and o 15% higher efficiency that engine strautified charge.

Vegetation health assessment by using airborne multispectral images throughout crop production cycles, among other precision agriculture technologies, is an important tool for modern agriculture practices. However, to really take advantage of crop fields imagery, specialized analysis techniques are needed. In this paper we present a geographic object-based image analysis (GEOBIA) approach to examine a set of very high resolution (VHR) multispectral images obtained by the use of small unmanned aerial vehicles (UAVs), to evaluate plant health states and to generate cropland maps for Capsicum annuum L. The scheme described here integrates machine learning methods with semi-automated training and validation, which allowed us to develop an algorithmic sequence for the evaluation of plant health conditions at individual sowing point clusters over an entire parcel. The features selected at the classification stages are based on phenotypic traits of plants with different health levels. Determination of areas without data dependencies for the algorithms employed allowed us to execute some of the calculations as parallel processes. Comparison with the standard normalized difference vegetation index (NDVI) and biological analyses were also performed. The classification obtained showed a precision level of about 95 % in discerning between vegetation and non-vegetation objects, and clustering efficiency ranging from 79 % to 89 % for the evaluation of different vegetation health categories, which makes our approach suitable for being incorporated at C. annuum crop’s production systems, as well as to other similar crops. This methodology can be reproduced and adjusted as an on-the-go solution to get a georeferenced plant health estimation.

In this paper it is proposed that one potential component by which the Musca domestica salivary gland hypertrophy virus (MdSGHV) infects individual flies is through cuticular damage. Breaks in the cuticle allow entry of the virus into the hemocoel causing the infection. Male flies typically have a higher rate of infection and a higher rate of cuticular damage than females. A model for the transmission of MdSGHV was formulated assuming several potential and recognized means of transmission. The model yields results that are in agreement with field data that measured the infection rate in house flies on dairy farms in Florida. The results from this model indicate that MdSGHV will be maintained at a stable rate within house fly populations and support the future use of MdSGHV as a birth control agent in house fly management.

The results of analysis of stress state of parts of gas-distribution mechanism of high-speed diesel.

On an example of designing a head of small-sized diesel engine MD-8 the technique and results of the analysis of a thermal condition of a design with use of toolkit Solid Works and COSMOS Works are resulted. It is shown, that existing in Autodesk Inventor the concept of the organization and construction of assembly units is most convenient in internal-combustion engine design in view of great volume of changing analyzed parameters.

Se evaluó el efecto del riego y fertilización sobre la calidad en postcosecha del zapote mamey (Pouteria sapota). Árboles de 20 años de edad provenientes de semilla fueron sometidos a dos frecuencias de riego por gravedad: tradicional (cada 10 días) y controlado a 20 milibares (cada 3 días); además, se evaluaron cuatro mezclas de nitrógeno (N), fósforo (P) y potasio (K): 0, 1, 1.5 y 2 kg de NPK al año, divididas en seis aplicaciones bimestrales. Las variables evaluadas en pulpa de frutos en madurez fisiológica (MF) y madurez comercial (MC) fueron: acidez, sólidos solubles totales (SST), firmeza, color (L,a,b), fenoles y carotenoides totales, pérdida de peso (PP) y concentración de NPK. El riego controlado a 20 mb mejoró la apariencia física de la pulpa (aumento del brillo) en MC e incrementó la concentración de carotenoides. La fertilización, también aumentó la concentración de carotenoides en frutos, mejorando su calidad y además, la pérdida de peso por transpiración fue menor respecto a los frutos de árboles no fertilizados. 2 kg de NPK causó mayor luminosidad en MC y 1.5 kg de NPK produjeron frutos con pulpa más roja. La disminución de la firmeza en frutos con MF causado por la fertilización con 1.5 y 2 kg de NPK, condiciona a un manejo cuidadoso del producto durante su cosecha y evitar heridas y golpes que afecten el proceso normal de maduración.

Recently, the use of small UAVs for monitoring agricultural land areas has been increasingly used by agricultural producers in order to improve crop yields. However, correctly interpreting the collected imagery data is still a challenging task. In this study, an automated pipeline for monitoring C. Annuum crops based on a deep learning model is implemented. The system is capable of performing inferences on the health status of individual plants, and to determine their locations and shapes in a georeferenced orthomosaic. Accuracy achieved on the classification task was 94.5. AP values among classes were in the range of [63,100] for plant location boxes, and in [40,80] for foliar area predictions. The methodology requires only RGB images, and so, it can be replicated for the monitoring of other types of crops by only employing consumer-grade UAVs. A comparison with random forest and large-scale mean shift segmentation methods which use predetermined features is presented. NDVI results obtained with multispectral equipment are also included.

Understanding both domestication processes and agricultural practices is an interdisciplinary endeavor. Ethnographic research is potentially helpful for reconstructing past events. Such knowledge is also crucial for documenting the links between biological and cultural diversity, as well as for future purposes such as innovation in food production and sustainability. Here, we review six ethnographic case studies in different pastoral socioecological systems of the American continent. The livestock species involved include the native South American camelids and Arctic reindeer, as well as some Old World species (mainly goats, sheep, and cattle). Starting with the Columbian exchange (15th-16th centuries) and continuing up to the present, Old World herbivores launched novel uses of the local flora which resulted in entirely new livelihoods and cultures, i.e., pastoralism with its variants. Three of these case studies approach specifically how herding ecologies (human–animal–plant relationships) stirred specific management practices (human–plant relationships) that in some instances have moved toward conscious human selection of plant phenotypes. The other examples correspond to three potential instances of similar ongoing processes that we propose on the basis of ethnobotanical and ethnozoological data that were produced separately by other authors. Based on the studies we have reviewed, along with additional information from other parts of the world, we are able to conclude that: (a) New World pastoralist societies are/have been continuously adding species to the humanity’s portfolio of useful plants; (b) animals have been aiding in this processes in different ways; and, (c) how human–animal–plant relationships unfold in the present could have been similar in the past, thus analogies may be proposed for explaining prehistoric multispecies interactions and their outcomes. With our review, we intend to bring more attention to contemporary pastoralists as plant managers, animals as agents in human-plant interactions, and domestication as a behavioral complex and multispecies process that is as important in the present or future as it was in the past. Our understanding of food production practices is not only fundamental for improving our current frameworks of governance, conservation, and restoration of useful species populations, but also of biocultural diversity altogether.