Manuel Abad

Bio: Manuel Abad is an academic researcher from King Juan Carlos University. The author has contributed to research in topics: Ostracod & Estuary. The author has an hindex of 30, co-authored 128 publications receiving 3552 citations. Previous affiliations of Manuel Abad include Polytechnic University of Valencia & University of Atacama.

Assessment of the fertiliser potential of digestates from farm and agroindustrial residues

Abstract: The sustainability of biogas production systems depends greatly on the appropriate disposal of the digestates produced. The main agrochemical characteristics of 12 digestates from the anaerobic co-digestion of farm and agroindustrial residues were determined and compared with quality standards to assess their potential use as fertilisers. The digestates have a high fertilising potential, associated mainly with their contents of NH4-N; however, their recycling in agriculture might be restricted by their Cu and Zn contents, salinity, biodegradability, phytotoxicity and hygiene characteristics, which must be addressed to obtain the maximum benefits. Such characteristics determine the need for applying pre- or post-treatments to increase digestate quality until acceptable levels. Therefore, digestate quality must be taken into account when managing the co-digestion process, including substrate selection, in order to use digestates as fertilisers without the additional cost of post-digestion conditioning treatments.

Influence of particle size on physical and chemical properties of coconut coir dust as container medium

Abstract: The influence of particle size (diameter between 2 mm) on the physical, physico-chemical and chemical properties of a coconut coir dust from Mexico was studied. Particle size significantly affected the physical properties, especially the air–water relationships. Air content increased and water-holding capacity (total and readily available) decreased with increasing particle diameter. The easily-available water content did not reveal a clear pattern of variation, showing the largest value in the fraction 0.125–0.25 mm. Particle size equivalent to 0.5 mm brought about an important and highly significant change in the physical properties studied. Coconut coir dust particle size also affected the physico-chemical and chemical characteristics, but to a lesser degree. Both the electrical conductivity and the available macro- and micro-element concentrations were significantly higher in the smaller size ranges, the largest values being obtained in the finest particle size fraction (<0.125 mm).

The Theory of Island Biogeography

Abstract: Preface to the Princeton Landmarks in Biology Edition vii Preface xi Symbols Used xiii 1. The Importance of Islands 3 2. Area and Number of Speicies 8 3. Further Explanations of the Area-Diversity Pattern 19 4. The Strategy of Colonization 68 5. Invasibility and the Variable Niche 94 6. Stepping Stones and Biotic Exchange 123 7. Evolutionary Changes Following Colonization 145 8. Prospect 181 Glossary 185 References 193 Index 201

A critical review on anaerobic co-digestion achievements between 2010 and 2013

Abstract: Anaerobic digestion is a commercial reality for several kinds of waste. Nonetheless, anaerobic digestion of single substrates presents some drawbacks linked to substrate characteristics. Anaerobic co-digestion, the simultaneous digestion of two or more substrates, is a feasible option to overcome the drawbacks of mono-digestion and to improve plants economic feasibility. At present, since 50% of the publication has been published in the last two years, anaerobic co-digestion can be considered the most relevant topic within anaerobic digestion research. The aim of this paper is to present a review of the achievements and perspectives of anaerobic co-digestion within the period 2010-2013, which represents a continuation of the previous review made by the authors [3]. In the present review, the publications have been classified as for the main substrate, i.e., animal manures, sewage sludge and biowaste. Animal manures stand as the most reported substrate, agro-industrial waste and the organic fraction of the municipal solid waste being the most reported co-substrate. Special emphasis has been made to the effect of the co-digestion over digestate quality, since land application seems to be the best option for digestate recycling. Traditionally, anaerobic co-digestion between sewage sludge and the organic fraction of the municipal solid waste has been the most reported co-digestion mixture. However, between 2010 and 2013 the publications dealing with fats, oils and greases and algae as sludge co-substrate have increased. This is because both co-substrates can be obtained at the same wastewater treatment plant. In contrast, biowaste as a main substrate has not been as studied as manures or sewage sludge. Finally, three interdisciplinary sections have been written for addressing novelty aspects in anaerobic co-digestion, i.e., pre-treatments, microbial dynamics and modeling. However, much effort needs to be done in these later aspects to better understand and predict anaerobic co-digestion.

Agricultural benefits and environmental risks of soil fertilization with anaerobic digestates: a review.

Abstract: Intensive soil fertilization with mineral fertilizers has led to several issues such as high cost, nitrate pollution and loss of soil carbon. Fertilization with organic matter such as compost therefore represents an alternative for sustainable agriculture. Traditional organic amendments such as manures, composts and sewage sludge have been extensively studied in the past. However, applications of biogas digestates and their impacts on the environment and human health are still unexplored. Recent articles report the agricultural potential and conflicting results of digestate performances. As a consequence, the effectiveness of digestate as organic amendment and fertilizer is still under debate. Here we review the legislative, chemical, agronomic and environmental literature on anaerobic digestates. We found that digestates can be considered as organic amendments or organic fertilizers, when properly handled and managed. Indeed we further show that anaerobic digestates have a higher potential to harm the environment and human health than undigested animal manures and slurries. The main points are the following: (1) Most solid digestates comply with the European organic matter minimal requirement for an organic amendment; (2) the fertilizer values of liquid digestates lie between those of livestock manures and inorganic fertilizers; (3) anaerobic digestates have higher NH3 emission potential than undigested animal manures and slurries and, consequently, pose a greater risk to the broad environment; (4) high Cu and Zn concentrations in digestates from co-digestion of pig and cattle slurry feedstock could jeopardize the sustainability of agricultural soils and (5) high Mn concentrations in digestates can induce Mn toxicity in agricultural soils, upon repeated applications.

Innovations in the Development and Application of Edible Coatings for Fresh and Minimally Processed Fruits and Vegetables

Abstract: One of the major growth segments in the food retail industry is fresh and minimally processed fruits and vegetables. This new market trend has thus increased the demands to the food industry for seeking new strategies to increase storability and shelf life and to enhance microbial safety of fresh produce. The technology of edible coatings has been considered as one of the potential approaches for meeting this demand. Edible coatings from renewable sources, including lipids, polysaccharides, and proteins, can function as barriers to water vapor, gases, and other solutes and also as carriers of many functional ingredients, such as antimicrobial and antioxidant agents, thus enhancing quality and extending shelf life of fresh and minimally processed fruits and vegetables. This review discusses the rationale of using edible coatings on fresh and minimally processed produce, the challenges in developing effective coatings that meet the specific criteria of fruits and vegetables, the recent advances in the development of coating technology, the analytical techniques for measuring some important coating functionalities, and future research needs for supporting a broad range of commercial applications.