Recycling of Nutrients

Insects such as the black soldier fly (BSF; Hermetia illucens) are currently being promoted as an alternative protein source for animals and organic waste management agents. To play the dual roles sustainably, there is need to reduce reliance on wild BSF and develop an appropriate farming methodology for the insect. This study aimed at improving larvae production in a black soldier fly colony previously established from the wild in Kenya. The study explored the effect of four locally available organic wastes as feedstocks for production the black soldier fly larvae. Separate feeding trials on faecal sludge (FS), banana peelings (BP), brewer’s waste (BW) and restaurant food waste (FR) was done and their effect on BSF larvae growth rate, larvae weight, total prepupal yield in grams, crude protein and lipid (ether extract) content analysed. The efficiency of the BSF larvae to consume and therefore reduce the waste load of the different substrates was also evaluated. Results showed that...

The aim of this paper is to compute the macronutrients mining by crops (output of nitrogen N, phosphorus P, and potassium K) and the addition through organic manure (input of N, P, K), in the barley (Hordeum vulgare L.) and wheat (Triticum aestivum L.) cultivation in a small, family managed farm, located in Hemis Shupkachan village, central Leh district. Moreover, a static balance is computed by measuring the difference between macronutrients contained in the manure spread on the fields, and in the crops harvested, without quantifying soil nutrient stock or the contributions from the rotation of crops. The evaluation is done at small farm level, < 1 hectare, because the majority of the District’s farmers, 62%, belong in this category. However results could lead to wider considerations regarding the importance of the traditional soil fertility practices in Ladakh.

Insects such as the black soldier fly (BSF; Hermetia illucens) are currently being promoted as an alternative protein source for animals and organic waste management agents. To play the dual roles sustainably, there is need to reduce reliance on wild BSF and develop an appropriate farming methodology for the insect. This study aimed at improving larvae production in a black soldier fly colony previously established from the wild in Kenya. The study explored the effect of four locally available organic wastes as feedstocks for production the black soldier fly larvae. Separate feeding trials on faecal sludge (FS), banana peelings (BP), brewer’s waste (BW) and restaurant food waste (FR) was done and their effect on BSF larvae growth rate, larvae weight, total prepupal yield in grams, crude protein and lipid (ether extract) content analysed. The efficiency of the BSF larvae to consume and therefore reduce the waste load of the different substrates was also evaluated. Results showed that...

The concept of waste recycling has been getting increasing attention in Saudi Arabia in recent years. The country produces around 15 million tons of municipal solid waste each year with an average daily rate of 1.4 kg per person. This rate is projected to double (30 million tons per year) by 2033 with current annual population growth rate of 3.4%. The major ingredients of Saudi Arabian municipal solid waste are food waste (40-51%), paper (12-28%), cardboard (7%), plastics (5-17%), glass (3-5%), wood (2-8%), textile (2-6%), metals (2-8%) etc. depending on the urban activities and population density of studied region.

This study attempts to contemplate the respondents’ behaviors regarding
recycling, with the purpose of identifying the factors that influence their behaviors. The
study is based on a survey that was conducted with 230 nationwide university students
and guidelines borrowed from the Theory of Planned Behavior and The Theory of
Reasoned action. The data collected was evaluated by applying the Structure Equation
Modelling technique. The study concluded that peoples’ attitudes are largely subject to
the moral values and general norms of their own society. Additionally, an individual’s
response towards recycling is greatly determined by the extent of his/her awareness
towards the environment, as well as his/her personal knowledge. Another conclusion
was that an individual’s past experience towards recycling contributes to his/her attitude
(willingness or apprehension about recycling) in the future. Furthermore, although the
convenience and cost of recycling were found to be reasonably significant determinants
about one’s recycling behavior, it was determined that time commitment is the most
decisive factor that influences an individual’s willingness to or not to recycle. The
study’s findings have not only established the authority of Theory of Planned Behaviour and Theory of Reasoned Action, but it has also presented propositions and
recommendations for future research. The inferences were based on the study’s respondents,
hence, so their validity can be applied to various scenarios involving local
educational institutions or government structures. The goal of the study is to encourage
people to engage in positive recycling behavior

Se presenta el plan de manejo ambientalmente amigable, de la Unidad de Manejo Ambiental El Tepez.  Es un programa integral, para las 42 hectáreas (420,000 metros cuadrados) de gran diversidad biótica, cuyo centro es un zoocriadero de tepezcuintle (agouti paca).  El Ejido Ursulo Galvan es la sede de la UMA, ubicado en el Municipio de Othón P. Blanco, Estado Libre y Soberano de Quintana Roo, Estados Unidos Mexicanos.

Makanan sebagai sumber protein, karbohidrat, lemak, vitamin, dan mineral sangat diperlukan bagi kesehatan fisik, pertumbuhan, dan mengatur proses metabolisme. Makanan yang berkualitas, aman dan menarik dapat diperoleh melalui perlakuan yang tepat pada setiap tahapan produksi, mulai dari persiapan, pengolahan, penyimpanan, pemasaran dan penggunaannya. Makanan yang tidak aman jika dikonsumsi dapat menimbulkan gangguan kesehatan bahkan berakibat pada kematian (Suryana, 1994, dalam Sundari, 2013). Undang-undang Nomor 7 Tahun 1996 menyatakan bahwa kualitas pangan yang dikonsumsi harus memenuhi beberapa kriteria, diantaranya adalah aman, bergizi, bermutu, dan dapat dijangkau oleh daya beli masyarakat. Aman maksudnya mencakup bebas dari cemaran biologis, mikrobiologi, kimia, logam berat, dan cemaran lain yang dapat mengganggu, merugikan dan membahayakan kesehatan manusia (Mudjajanto, 2014). Dalam Islam dikenal dengan istilah makanan halalan thayyiban. Makanan halalan (halal) yaitu makanan yang tidak diharamkan, dan tidak menyalahi hukum syari`at Islam untuk dikonsumsi sesuai Al-Qur'an dan sunnah nabi. Makanan yang baik atau dalam istilah agama thayyiban yaitu baik dari sudut pemenuhan kebutuhan gizi bagi tubuh, pengolahan makanan baik, dan bahan campuran yang baik. Saat ini, Industri pangan di Indonesia telah berkembang dengan pesat, ditandai dengan munculnya industri kecil dan industri rumah tangga yang 1

Previous and current agricultural practices have contributed to environmental pollution, which is further affecting food security, human health, and climate. Yet, agriculture cannot be eliminated, because, of its promising role in ending hunger, reducing poverty, improving nutrition, and achieving food security in low-middle income countries. Hence, there is a need for shift from 'unclean' practices to sustainable practices. Similarly, differences in pollution, among nations call for regional changes or intervention in agri-food practices to reduce global pollution. These practices are essential for African and Asian countries. Of the many methods proposed in this review, localized technology improvement and globalized sustainable intensification are of high impact models having the potential of mitigating greenhouse gases up to an extent of 30%. Various methods of achieving these measures include, but not limited to, the shift in management systems of crop and livestock production, encouraging agriculture and veterinary practices with less environmental impact and high adaptation, enabling nutrient recycling or recovery, resource-use efficiency, mitigation of nitrous oxide and methane from soil, implementation of integrated farming system and insect farming. Government agencies along with agri-food producers, processors, and farmers must be ready to change their current agricultural practices by adopting new methods. The review conclude that the sustainable agricultural production is possible through the use of low-priced local resources that are capable of increasing soil carbon storage, thus combating the pollution in countries with a transition economy.

Abrupt sunlight reduction scenarios (ASRS) following catastrophic events, such as a nuclear war, a large volcanic eruption or an asteroid strike, could prompt global agricultural collapse. There are low-cost foods that could be made available in an ASRS: resilient foods. Nutritionally adequate combinations of these resilient foods are investigated for different stages of a scenario with an effective response, based on existing technology. While macro-and micronutrient requirements were overall met, some-potentially chronic-deficiencies were identified (e.g., vitamins D, E and K). Resilient sources of micronutrients for mitigating these and other potential deficiencies are presented. The results of this analysis suggest that no life-threatening micronutrient deficiencies or excesses would necessarily be present given preparation to deploy resilient foods and an effective response. Careful preparedness and planning-such as stock management and resilient food production ramp-up-is indispensable for an effective response that not only allows for fulfilling people's energy requirements, but also prevents severe malnutrition.

"E-waste" is a popular, informal name for electronic products nearing the end of their "useful life. "Ewastes are considered dangerous, as certain components of some electronic products contain materials that are
hazardous, depending on their condition and density. The hazardous content of these materials pose a threat to human health and environment. Discarded computers, televisions, VCRs, stereos, copiers, fax machines, electric lamps, cell phones, audio equipment and batteries if improperly disposed can leach lead and other substances into soil and
groundwater. Many of these products can be reused, refurbished, or recycled in an environmentally sound manner so that they are less harmful to the ecosystem. This paper highlights the hazards of e-wastes, the need for its appropriate management and options that can be implemented.

Insects such as the black soldier fly (BSF; Hermetia illucens) are currently being promoted as an alternative protein source
for animals and organic waste management agents. To play the dual roles sustainably, there is need to reduce reliance on
wild BSF and develop an appropriate farming methodology for the insect. This study aimed at improving larvae production
in a black soldier fly colony previously established from the wild in Kenya. The study explored the effect of four locally
available organic wastes as feedstocks for production the black soldier fly larvae. Separate feeding trials on faecal sludge
(FS), banana peelings (BP), brewer’s waste (BW) and restaurant food waste (FR) was done and their effect on BSF larvae
growth rate, larvae weight, total prepupal yield in grams, crude protein and lipid (ether extract) content analysed. The
efficiency of the BSF larvae to consume and therefore reduce the waste load of the different substrates was also evaluated.
Results showed that BSF larvae fed on FR had significantly higher (P<0.05) total mean yield and average individual weight
of 196.9±4.0 g and 0.101±0.002 g, respectively, followed by BW (154.8±6.5 g, 0.078±0.02 g), FS (138.7±5.0 g, 0.070±0.001
g) and with BP the lowest (108.9±5.6 g, 0.055±0.002 g). The harvested BSF larvae crude protein was significantly higher
for FS and BW at 45.4±0.1% and 43.0±1.0%, respectively. However, ether extract content was variable and dependent
on feedstock used with lower values reported for FS and BW (18.1±0.3% and 27.2%, respectively), and highest for food
remains prepupa (36%). Dry matter reduction ranged between 50.3-81.8% with corresponding bioconversion and feed
conversion rates ranging from 14.9-20.8% and 2.6-4.5, respectively, was achieved for the substrates used. These results
indicated the potential of utilising BSF composting in valorisation of the local organic wastes for their bioremediation from
the environment. Due to their availability in large quantities and their low cost, these organic wastes can form important
feedstock resources for the sustainable production of BSF larvae as a future alternative protein source for both animal
feeds at farm level and industrial scale. In conclusion, embracing nutrient recycling through BSF technology by resource constrained
farmers in Kenya will contribute to food security through supply of proteins for production of poultry and fish.
Keywords: bioremediation, food remains, banana peels, bioconversion rate, value addition.

Increasing urbanization and industrialization have resulted in a dramatic increase in the volume of wastes generated worldwide. The treatment of wastewater results in large amounts of municipal treated sewage sludge, or biosolids. Sludge has traditionally been disposed through ocean-dumping, landfilling, or incineration. But due to increasingly stringent environmental regulations, these disposal methods are being phased out. With increasing populations worldwide, biosolids production is likely to continue to increase in a near future. The safe disposal of biosolids is a major environmental challenge. Land application of biosolids is largely considered the best option of disposal because it offers the possibility of recycling plant nutrients, provides organic material, improves soil's chemical and physical properties and enhances crop yields. The use of biosolids is increasingly being considered as a feasible and technical solution to reverse degraded and less productive lands, and to promote the reestablishment of a vegetative cover. However, benefits have to be carefully weighed against potential deleterious effects related to non-point source pollution. Environmental risks include increased potentially trace elements (PTE) input, leaching of nitrogen (N) in subsurface drainage and groundwater, contamination of surface water with soluble and particulate phosphorus (P), vector attraction, and reduced air quality by emission of volatile organic compounds, among others. Most countries regulate concentrations of PTE and pathogens in biosolids and mandate maximum permissible loading rates into soil to manage contaminants. Nevertheless, concerns associated with adverse environmental effects due to land application of biosolids continue. This chapter investigates the environmental impact of biosolids land application related to soil properties. * torri@agro.uba.ar.

How to cite this book Chapter:
Torri S, Cabrera M. 2017 Environmental impact of biosolids land application. In: Organic Waste: Management Strategies, Environmental Impact and Emerging Regulations, Editor: M Collins, Nova Science Publishers, Inc., Hauppauge, NY 11788, ISBN: 978-1-53610-936-8, 185-208, 226 pp

This study presents an example of blackwater (0.8 L flush water, faeces, urine and toilet paper) composting from low-flush vacuum toilets, which is a part of a pilot-scale source separation system at a remote tourist facility. Blackwater (BW) was collected from vacuum toilets into a tank and applied over peat filters for particle retention and dewatering on the gravity principle to obtain a solid fraction (SF). Before composting, SF was mixed with pine bark and wheat bran. With no mixing, the thermophilic phase was achieved only in the middle layer and lasted for three weeks. Sanitation was indicated by the inactivation of enterobacterial pathogens, the absence of parasites, and the cessation of phytotoxicity (cress seed germination index !80%). High temperatures and high levels of NH 4 þ in the collecting tank, the peat filters and six weeks of SF composting are plausible reasons for the reduction of pathogens. At the end of composting, the NH 4 þ eN/NO 3 À eN mass ratio was between 0.5 and 3.0, which indicates mature compost that is ready for use in agriculture. In terms of the percentage of dry matter, the nutrients were nitrogen: phosphorus: potassium ¼ 3.0:3.2:1.6, with a favourable ratio of C:N ¼ 10, indicating the biological stability of the produced compost. The tested pilot-scale model has thus proved that the composting of SF is a viable option as a part of the separation system.

Anthroponics is a recirculating soilless agriculture system that uses natural bacterial cycles to convert human biowaste into plant fertilizer. In this investigation the concept of anthroponics and the underlying processes are explained, and an overview on the existing knowledge of urine and anthroponics systems is also presented.

A small experiment was conducted in Malmö, Sweden. The method involved building three anthroponic systems and collecting urine samples from one healthy individual. The objective was to calculate an average and median time for urine volatilization to ammonia, and to cultivate Lactuca sativa in the anthroponic systems under different dosages of urine. The systems were tested for Total Ammonia Nitrogen (NH4+/NH3), Nitrite (NO2-), Nitrate (NO3-), Electrical Conductivity (EC) and pH.

The first batch of urine had an average volatilization time of 4,7 weeks and a median volatilization time of 5 weeks. The second batch of urine had an average volatilization time of 4,7 weeks and a median volatilization time of 4 weeks. The third batch of urine had an average volatilization time of 4 weeks and a median volatilization time of 2 weeks. For the anthroponic systems, the aged urine used to cycle the systems and create the bacterial colony was sufficient to grow all of the crops from seedling to harvest, thus diverging from the original protocol. Each system used 100mL of aged urine during a total period of 35 days: System 1 produced 225g of lettuce, System 2 produced 221g of lettuce, and System 3 produced 180g of lettuce.

In conclusion, the average amount of urine produced by an adult human per day can grow around 3kg of lettuce. Current requirements for ageing urine for safe anthroponic use take a long time for any scalable solution in agriculture or wastewater treatment. Better measuring techniques, longer testing periods and more research is recommended in this field in order to draw an improved representative conclusion.

Background The objective of this study was to develop a consortium of effective microorganisms to hasten the composting process and to reduce the composting period. Results An efficient microorganism (EM) consortium was developed using Candida tropicalis (Y6), Phanerochaete chrysosporium (VV18), Streptomyces globisporous (C3), Lactobacillus sp. and enriched photosynthetic bacterial inoculum for rapid composting of paddy straw. Paddy straw was amended with poultry droppings to narrow down its C:N ratio for faster degradation. Composting was carried out in open pits with EM consortium and compared with compost inoculant (CI) consisting of Aspergillus nidulans (ITCC 2011), Trichoderma viride (ITCC 2211), Phanerochaete chrysosporium (NCIM 1073) and A. awamori (F-18). Changes in biochemical and physiochemical parameters like C:N ratio, pH, EC and humus were studied over a period of 60 days to test compost maturity and stability along with microbial and extracellular hydrolytic enzyme activities. Paddy straw amended with EM and CI hasten the composting process by bringing C:N ratio down to 15:1 and achieving a total humus content of 4.82 % within 60 days. High activity of hydrolytic enzyme carboxymethyl cellulase (CMCase) (0.43 IU/g) and microbial activity in terms of dehydrogenase (158.64 lg TPF/g/day) was observed in this treatment. The activity of xylanase was positively correlated (r = 0.987) with alkali-soluble carbon.

District heating networks are commonly addressed in the literature as one of the most effective solutions for decreasing the greenhouse gas emissions from the building sector. These systems require high investments which are returned through the heat sales. Due to the changed climate conditions and building renovation policies, heat demand in the future could decrease, prolonging the investment return period. The main scope of this paper is to assess the feasibility of using the heat demand – outdoor temperature function for heat demand forecast. The district of Alvalade, located in Lisbon (Portugal), was used as a case study. The district is consisted of 665 buildings that vary in both construction period and typology. Three weather scenarios (low, medium, high) and three district renovation scenarios were developed (shallow, intermediate, deep). To estimate the error, obtained heat demand values were compared with results from a dynamic heat demand model, previously developed and validated by the authors. The results showed that when only weather change is considered, the margin of error could be acceptable for some applications (the error in annual demand was lower than 20% for all weather scenarios considered). However, after introducing renovation scenarios, the error value increased up to 59.5% (depending on the weather and renovation scenarios combination considered). The value of slope coefficient increased on average within the range of 3.8% up to 8% per decade, that corresponds to the decrease in the number of heating hours of 22-139h during the heating season (depending on the combination of weather and renovation scenarios considered). On the other hand, function intercept increased for 7.8-12.7% per decade (depending on the coupled scenarios). The values suggested could be used to modify the function parameters for the scenarios considered, and improve the accuracy of heat demand estimations. Abstract In the Kingdom of Saudi Arabia (KSA), millions of worshippers come from across the globe to perform religious rituals of Pilgrimage (Hajj) and Umrah. Madinah-tul-Munawara is one of the holiest city, where pilgrims come after performing rituals in Makkah. In this city, most of the collected municipal solid waste (MSW) is disposed of in the landfills after a partial recycling of paper, cardboard, and metals (~10-20% of total MSW). The Saudi's government has recently launched a new policy of Vision 2030, which outlined the safeguard of local environment through increased efficiency of waste recycling and management, pollution prevention strategies and generating renewable energy from indigenous sources, including the waste. Currently, the recycling practices in KSA are mainly regulated by an informal sector through waste pickers or waste scavengers. This has led to the need of recycling schemes, especially in the holiest cities of Makkah and Madinah through a public-private partnership (PPP). Huge amounts of energy can be conserved, that would otherwise be spent on raw material extraction, transportation, and manufacturing of materials, through recycling into the same materials. Around 10,009 TJ of energy can be saved through recycling of 24.21% of MSW in Madinah city, including glass, metals, aluminum, cardboard, and paper. It is estimated that around 10,200 tons of methane (CH4) emissions and 254,600 Mt.CO2 eq. of global warming potential (GWP) can also be saved. In addition, carbon credit revenue of US $5.92 million, and landfill diversion worth of US $32.78 million can be achieved with a net revenue of US $49.01 million every year only by recycling 24.21% of MSW in Madinah city. The waste recycling doesn't require high technical skills and labor, and complicated technologies for large-scale implementation, and therefore, can be implemented easily in the holiest cities of Makkah and Madinah to achieve multiple economic and environmental benefits. Abstract In the Kingdom of Saudi Arabia (KSA), millions of worshippers come from across the globe to perform religious rituals of Pilgrimage (Hajj) and Umrah. Madinah-tul-Munawara is one of the holiest city, where pilgrims come after performing rituals in Makkah. In this city, most of the collected municipal solid waste (MSW) is disposed of in the landfills after a partial recycling of paper, cardboard, and metals (~10-20% of total MSW). The Saudi's government has recently launched a new policy of Vision 2030, which outlined the safeguard of local environment through increased efficiency of waste recycling and management, pollution prevention strategies and generating renewable energy from indigenous sources, including the waste. Currently, the recycling practices in KSA are mainly regulated by an informal sector through waste pickers or waste scavengers. This has led to the need of recycling schemes, especially in the holiest cities of Makkah and Madinah through a public-private partnership (PPP). Huge amounts of energy can be conserved, that would otherwise be spent on raw material extraction, transportation, and manufacturing of materials, through recycling into the same materials. Around 10,009 TJ of energy can be saved through recycling of 24.21% of MSW in Madinah city, including glass, metals, aluminum, cardboard, and paper. It is estimated that around 10,200 tons of methane (CH4) emissions and 254,600 Mt.CO2 eq. of global warming potential (GWP) can also be saved. In addition, carbon credit revenue of US $5.92 million, and landfill diversion worth of US $32.78 million can be achieved with a net revenue of US $49.01 million every year only by recycling 24.21% of MSW in Madinah city. The waste recycling doesn't require high technical skills and labor, and complicated technologies for large-scale implementation, and therefore, can be implemented easily in the holiest cities of Makkah and Madinah to achieve multiple economic and environmental benefits.

The paper examines the biowaste management issues across rural areas of Romania in the context of
poor waste management infrastructure in the last decade (2003-2012). Biowaste is the main fraction of
municipal waste, thus a proper management is a key challenge in order to sustain a bioeconomy in the
near future. The amount of biowaste generated and uncollected by waste operators is generally uncontrolled
disposed if not recovered through home composting. The paper points out the role of home composting in diverting the biowaste from wild dumps and landfills for the regions covered or not by waste collection services. Home composting and the biowaste losses are further assessed based on several scenarios (worse-case, pessimistic, realistic, optimistic) where the net loads of greenhouse gasses (GHG) are calculated at national and regional levels. The transition of home composting techniques, from open piles to plastic bins with respect to standard guidelines will improve the home composting performance in terms of compost quality and net GHG's savings, supporting a bio-based economy which will lead towards a sustainable rural development. Regional disparities are revealed across Romanian
counties and the paper opens new research perspectives regarding which options should be adopted by
counties and rural municipalities in the biowaste management process.

Launched in May 2011, the new global magazine Southern Innovator is about the people across the global South shaping our new world, eradicating poverty and working towards the achievement of the Millennium Development Goals (MDGs).
They are the innovators.

Issue 1 covered the theme of mobile phones and information technology. Issue 2 covered the theme of youth and entrepreneurship. Issue 3 covered the theme of agribusiness and food security. Issue 4 covered the theme of cities and urbanization. Issue 5 covers the theme of waste and recycling.

Abrupt sunlight reduction scenarios (ASRS) following catastrophic events, such as a nuclear war, a large volcanic eruption or an asteroid strike, could prompt global agricultural collapse. There are low-cost foods that could be made available in an ASRS: resilient foods. Nutritionally adequate combinations of these resilient foods are investigated for different stages of a scenario with an effective response, based on existing technology. While macro- and micronutrient requirements were overall met, some—potentially chronic—deficiencies were identified (e.g., vitamins D, E and K). Resilient sources of micronutrients for mitigating these and other potential deficiencies are presented. The results of this analysis suggest that no life-threatening micronutrient deficiencies or excesses would necessarily be present given preparation to deploy resilient foods and an effective response. Careful preparedness and planning—such as stock management and resilient food production ramp-up—is ind...

RESUMEN
El tamo de arroz es uno de los residuos agrícolas lignocelulósicos más abundantes en el planeta, luego de los residuos producidos por los cultivos de maíz y trigo, con una producción mundial estimada de 1000 millones de toneladas según estadísticas de la FAO. En el contexto de la agricultura moderna es determinante lograr un manejo ambientalmente sostenible de este recurso me-diante su incorporación al suelo, de tal forma que se logre el reciclaje de nutrientes, evitando la incorporación de patógenos al sistema y la inmovilización de elementos como el nitrógeno por la comunidad microbiana. El objetivo de este trabajo consistió en la evaluación de un inoculo microbiano mixto a partir de productos comerciales basados en hongos del género Trichoderma y bacterias aerobias formadoras de endosporas, con potencial degradador del tamo de arroz, así como el empleo de bacterias pro-motoras de crecimiento vegetal al momento de la siembra, que pudieran aprovechar los nutrientes del proceso de descomposi-ción del tamo de arroz, potenciando su actividad biológica. Los tratamientos fueron evaluados bajo diferentes relaciones C:N del tamo de arroz que favorecieran el proceso de degradación, mediante la adición de nitrógeno inorgánico. Los resultados del traba-jo permitieron identificar que la aplicación de una enmienda de nitrógeno a una relación C:N 35 más una dosis adicional de urea al momento de la siembra de las semillas de arroz, fue el tratamiento más adecuado para potenciar el efecto de los microorganis-mos e incrementar las variables agronómicas obtenidas mediante un esquema de fertilización convencional del cultivo. Palabras clave: Tamo de arroz; relación C:N; Trichoderma spp.; reciclaje de nutrientes; promoción de crecimiento vegetal en arroz.
ABSTRACT
Rice straw is one of the most abundant lignocellulosic agricultural residues on the world, after residues produced by maize and wheat crops, with an estimated global production of 1000 million tones according to FAO statistics. In the context of modern agriculture, it is essential to achieve an environmentally sustainable management of this resource, through the incorporation of rice straw into the soil, in order to achieve nutrient recycling avoiding the incorporation of pathogens into the system and the

This paper presents an example of the importance of evapotranspiration in constructed wetlands, with vertical subsurface flow, comparing different methods of treatment efficiency calculations and discussing the influence of evapotranspiration on removal rates. The application of reed, marked by high transpiration ability, is a cheap and effective method of landfill leachate disposal. A 2-year study examined the effectiveness of leachate treatment in constructed wetlands with reed. Two kinds of vertical subsurface flow systems: first with sand, and second with combined two layers of sewage sludge and sand has been tested. 1, 3, and 5 mm d−1 hydraulic loading rates of landfill leachate have been applied. Daily evapotranspiration was in the range from 0.98 to 2.99 mm d−1 in the first year of research and from 2.56 to 4.61 mm d−1 in the second year. The influence of evapotranspiration rate on chemical oxygen demand (COD) removal rate was examined. Two methods of removal efficiency calculation have been used: first based on inlet and outlet COD concentrations, second on mass balance determination. Research showed that the removal efficiency calculated as a comparison between initial and final concentration is significantly lower, than expected from mass balance, especially, when higher hydraulic loading rates were applied.

Western Kenya is one of Africa’s most densely populated rural areas, characterised by intensive smallholder crop–livestock systems on degraded lands managed with small inputs of mineral fertiliser and animal manure. Competing uses for crop residues and other organic resources often results in poor nutrient cycling efficiencies at farm scale. Modifying livestock feeding, retaining more crop residues in the field, and improving manure management can help conserving considerable amount of nutrients on-farm. To examine to what extent such strategies would be feasible, we analysed whole-farm nutrient cycling efficiencies (NCE) of a range of farms differing in resource-endowment and production orientation, identifying the most efficient farmer strategies considering labour and financial constraints. Nutrient concentration in excreted cattle manure was relatively small (i.e., N < 1.7%; P < 0.6%). Current manure management practices led to low NCE’s (average 27%) due to nutrient losses from excretion through storage and application. Farmers have few incentives to improve manure management given the small amounts of excreta and nutrients to be recycled. Yet, manure, both composted and fresh, represented the greatest N (16 kg ha−1 season−1) and C returns to the soil (312 kg C ha−1 season−1). Retention of crop residues was the cheapest source of nutrient inputs for the next crop, especially when compared with manure, but farmers prioritised its use for cattle feeding. Our findings highlight the critical lack of nutrients and organic residues on smallholder farms in the densely-populated highlands of East Africa, as well as low NCE when it comes to manure. In these conditions, efficient nutrient cycling for manure and improved cattle feeding are essential to increase use efficiencies of any possible external nutrient added in these farms.

A novel ammonia stripping method, including a CO 2 pre-stripper was used to treat a mix of supernatant liquor from an anaerobic digester and urine in order to recycle nitrogen as ammonium sulfate at full-scale in the WWTP Kloten/Opfikon. Waste streams were not generated, since the ammonia was recovered as a marketable nitrogen fertilizer, turning a waste product into a valuable product. The efficiency of this system was increased by means of the addition of pre-treated urine collected separately at EAWAG building. The separation step was performed by the use of water free urinals and urine diversion flush toilets. An increase of 10% in the liquid flux with the addition of the urine translated into a 40% increase of the ammonia concentration in the inlet of the stripping unit. The achievement of these percentages generated a proportional increase in the fertilizer production. The urine pre-treatment was carried out by adding magnesium to produce a precipitate of struvite. The first experiments with the combined treatment showed the feasibility of the combination of the separation and pre-treatment steps.

Background Disposal of vegetable waste in landfills and illegal sites leads to emission of greenhouse gases and leachate production, thereby imposing major environmental issues. As an alternative, this waste can be successfully recycled for its high nutrient content using composting process. Results Five trials were made with the ratio of 6:3:1 of trial 1 (50 kg), trial 2 (70 kg), trial 3 (90 kg), trial 4 (120 kg) and trial 5 (150 kg) by adding 10 kg of dry leaves in each of the trials as bulking agent.

This book presents the most successfull programe of cooking oil recycling  from Brazil. The CEO of Recoleo Co. Nivia Freitas and the UFMG Prof. Ricardo MP Coelho explain the program using a clear and objetive style aimed to attrack local decision makers to support new firmas of cooking oil recycling in the country.

Nitrogen loss from applied fertilizer can be a significant environmental quality issue if NO3 moves to surface or ground water. The Iowa nutrient reduction strategy science assessment identified winter cereal rye (Secale cereal L.) cover crop as a practice that can significantly reduce N and P loss (41% NO3-N and 21% P reduction) from corn (Zea mays L.) and soybean [Glycine max. (L.) Merr.] fields. Cereal rye, when used as a cover crop, through its fibrous root system is able to explore the soil and use residual NO3N. In order to further understand the effectiveness of rye as a cover crop for scavenging and recycling N, there is a need to understand the amount of root/shoot biomass and N and carbon (C) partitioning between roots and shoots at the time of rye termination. This study was conducted at the Climate and Corn-Based Cropping Systems Coordinated Agricultural Project (CSCAP) cover crop site, located at the Ag. Engineering and Agronomy Research Farm, Iowa State University near...

Anaerobic digestion is often applied for biological conversion and valorization of organic waste, waste water and other biomass sources as renewable energy and biofuel in the form of biomethane. Composition of the material remaining after digestion, or digestate, is highly dependent on processed feedstocks. This by-product is usually rich in nutrients such as nitrogen and phosphorus, so it is potentially reusable as fertilizer or nutritive broth in agricultural systems. Alternatively, the digestate may need post-treatment based on nutrient removal or recovery strategies. The use of life-cycle assessment tools is becoming popular to analyze nutrient handling scenarios. This study reviews, through a bibliometric-based approach, the research outputs and global trends in the area of knowledge of nutrient management from digestates in the last 30 years, 2017 included. Documentary production followed an upward trend, with a relative productivity in the last 3 years greater than 37% of the total number of appeared publications. China, USA and Spain were the three most prolific countries. The particular interest in nutrient management alternatives and its evolution were identified. Trends for promoting sustainability include low environmental impact, holistic agro-energy solutions, reduced consumption of resources during digestate processing, and circular economy scenarios based on concepts such as (bio)refinery and recovery of valuable and marketable products.

One of the major concerns regarding municipal wastewater treatment plant discharge is the rising concentration of nutrient compounds, specifically nitrogen and phosphorus.
Nitrogen and phosphorus are the primary causes of cultural eutrophication (i.e., nutrient enrichment due to human activities) in surface waters. The most recognizable manifestations of this eutrophication are algal blooms that occur during the summer. Chronic symptoms of over-enrichment include low dissolved oxygen, fish kills, murky water, and depletion of desirable flora and fauna.

In this paper, a process that can simultaneously, but independently recover nitrogen and phosphorus from wastewater will be presented. This process can enable municipalities to develop useful fertilizer products from the nitrogen and phosphorus, that are present in wastewater.

The lack of space and opportunity for development have been identified as key reasons behind the stagnation of the European aquaculture industry. With the historical loss and degradation of current European wetlands there is an opportunity for harnessing the commercial investment of the aquaculture industry in construction of dual purpose wetlands that incorporate both conservation and extensive aquaculture activities. These wetlands can be used to expand the area available to suitable aquaculture into ecologically sensitive areas, such as Natura 2000 sites. Veta la Palma (VLP) situated in the Doñana Natural Park (and a Natura 2000 site) is an example of such an aquaculture development and a possible model for future opportunities. In the current study some of the important ecosystem services that are provided by VLP are assessed. The provisioning services of VLP were the economic rationale for the investment and more than 820 tonnes yr-1 of fish and shrimp is produced, through a mixture of semi-extensive and extensive aquaculture. The regulating services include nutrient absorption, and the flow of river water through VLP and high primary production results in the absorption of 377 tonnes of dissolved inorganic nitrogen yr-1, and 516 tonnes of C yr-1. Supporting services include the provision of habitat for more than 94 bird and 21 fish species. The primary production that supports the birds, extensive and semi-extensive aquaculture production was also estimated to be 167,000 t, 50,000 t and 133,000 t yr-1, respectively. The losses to birds are substantial and these estimates indicate that almost half of the primary production supports the wetland birds which directly consume 249 tonnes of fish and 2578 tonnes of invertebrates per annum. However it is the ecological credentials of the farm that enable premium prices and hence ensure the economic viability of the farm. The study demonstrates the possibility of using aquaculture to mitigate the historical loss of wetlands, provide significant ecosystem services and contribute to achievement of the European environmental legislative goals, and furthers the opportunity for the expansion of aquaculture into sensitive but impacted habitats.

Nanoencapsulation/nanocarrier systems like nanoemulsions, nanoliposomes, solid lipid nanoparticles, biopolymeric nanocarriers, nature-inspired nanocapsules, have been shown with the capacity to encapsulate food constituents. To understand the current status of nanoencapsulation of food, the authors examined recently published reviews and deemed further synthesis regards the aspects applied to (food) bioactive constituents needful. In this paper, the nanoencapsulation of food bioactive constituents and its associated processes was revisited. How nanoencapsulation delivers and same time protects the bioactivity of nutrients, nutraceuticals, and other food constituents is discussed. The major bioavailability methods employed to nanoencapsulate nutrients, nutraceuticals, and other food components, which include emulsification, coacervation and supercritical fluid; inclusion complexation, emulsification solvent evaporation, and nanoprecipitation; electrospraying and electrospinning, are tersely summarized. Diverse methodologies employed during the nanoencapsulation of food constituents has enabled the delivery and protection of nutrients, nutraceuticals and other bioactive ingredients.

This paper presents an example of the importance of evapotranspiration in constructed wetlands, with vertical subsurface flow, comparing different methods of treatment efficiency calculations and discussing the influence of evapotranspiration on removal rates. The application of reed, marked by high transpiration ability, is a cheap and effective method of landfill leachate disposal. A 2-year study examined the effectiveness of leachate treatment in constructed wetlands with reed. Two kinds of vertical subsurface flow systems: first with sand, and second with combined two layers of sewage sludge and sand has been tested. 1, 3, and 5 mm d −1 hydraulic loading rates of landfill leachate have been applied. Daily evapotranspiration was in the range from 0.98 to 2.99 mm d −1 in the first year of research and from 2.56 to 4.61 mm d −1 in the second year. The influence of evapotranspiration rate on chemical oxygen demand (COD) removal rate was examined. Two methods of removal efficiency calculation have been used: first based on inlet and outlet COD concentrations, second on mass balance determination. Research showed that the removal efficiency calculated as a comparison between initial and final concentration is significantly lower, than expected from mass balance, especially, when higher hydraulic loading rates were applied.

Soil nutrient cycling in the soil-plant system of crops relies on the effects of the agronomical practices on soil conditions, especially soil microbial population mediating soil carbon transformation (either mineralization or stabilization), nitrogen cycle including soil nitrogen transformation, uptake and return from plants, and nitrogen losses, and the fate of other elements mediating these trade-offs, including phosphorous. Arbuscular mycorrhizal fungi (AMF) are widespread, soil-borne microbes living in an obligate symbiotic status with most of the land plants. Such symbiosis can bring considerable benefits to plant growth, uptake of nutrients, and soil conditions. However, such benefits are not frequently seen in the field since the agronomical practices, especially tillage and use of fungicides, impair its development, which can partly be overcome by inoculation. Also, the increase of CO2 concentration with climate change and nitrogen fertilization could negatively affect the ...

The EU is currently addressing the problem of depletion of phosphate, which is a source of phosphorus. Due to the usage of modern digestate treatment enabling macroelements recycling, the digestate can be a suitable substitute for anorganic fertilizers. This experiment is focused on improving the soil properties due to digestate application in sugar beet growing region. Applicated digestate comes from a biogas plant of agricultural cooperative Velešovice. The obtained results show better physical properties (soil structure, stability of soil aggregates) and differences in pH values, Cox (%) and nutrient content between variants.

The present work leads to sustainability (responsible management of resources consumption) of both paper and sugar industries. It, simultaneously, upgrades recycled waste paper (namely old newsprint) and creates a new use for molasses (an important byproduct of the sugar industry). This study introduces -for the first time world wide- a novel environmentally safe approach to upgrade recycled natural cellulose fibers (waste paper namely old newsprint), for use as specialty paper green nanocomposites suitable for several advanced purposes. The recycled cellulose fibers are upgraded by increasing their alpha cellulose content, and restoring their natural nanoporous structure, which is -normally- collapsed due to the first cycle of papermaking. Molasses is then incorporated into this restored nanoporous structure to obtain paper green nanocomposites filled with kaolin in presence of molasses. In comparison to conventionally recycled waste paper, the green paper nanocomposites -produced in this work- exhibit high dry and wet strength, and a surprisingly tremendous retention of inorganic fillers used in papermaking. This was achieved through a green nanotechnology process, where the solvent used is water (the ideal green solvent). The input and output components are renewable environmentally safe materials i.e. waste paper (cellulose fibers) and molasses (a by product of the sugar industry). The procedures used are simple physical processes conducted at room temperature rather than hazardous chemical reactions. Thus, saving energy, and decreasing the risk of chemical and thermal accidents, pollutive releases, explosions, and fires.

Demand for rice in Uganda surpasses the supply and results in importation of over 30% of the rice consumed. Actual rice yields are still very low (1.5 t ha-1) compared to the potential yield (8 t ha-1). Therefore, this study aimed at establishing the major limiting nutrients and estimation of optimum fertilizer requirements for lowland rice for increased and sustainable production. The study was conducted in two seasons Eastern Uganda. Two sets of trials were conducted; nutrient omission trial for estimating indigenous nutrient supply of the major nutrients and response function and the recovery efficiency trial for estimating recovery of applied Nitrogen. Both
experiments were laid in a RCBD, where the first one involved 8 treatments of NPK (t0, t1, t2, t4, t5, t6, t7 and t8) each at different rates. While the second experiment involved two treatments (t0 and t1) of N fertilizer. Applications of nitrogen significantly increased yield components and consequently the grain yield of rice. The major limiting nutrient for lowland rice production is nitrogen and the soil nitrogen supplying potential can support yield target of 2.8 t ha-1. Whereas, the indigenous Phosphorus and Potassium supply can support yield target of up to 9 t ha-1 and therefore, not limiting at achievable yield targets of 6 tha-1. Use of internal efficiencies was promising in analysis of nutrient status and nutrient requirement to achieve the specific yield targets. 65 kg N ha-1 is the optimum rate for lowland rice and this corresponds to a target yield of 5 t ha-1. Get more articles at: http://www.innspub.net/volume-7-number-2-august-2015-ijaar/

"In the present study, a monolithic alumina coated microfiltration ceramic membrane was used for solid particulates removal and nutrients recovery from anaerobic digester complex effluent streams. The aim was to test the effect of the cake layer developed by the solids, on the surface of the membrane channels, to the filterability of these materials. The solids content ranged between 2.6 g/L to 15.1 g/L. During practical application, two processing techniques targeting the enhanced recovery of the materials of interest including ammonia, phosphate, calcium bicarbonate and volatile fatty acids, namely dewatering and diafiltration, were used. These had an immediate effect on the solids content (PDS 13μm to 3.97μm) enhancing the filterability of the effluents. Their processability was evaluated in terms of flux, cross flow velocity, membrane resistance and cake resistance. Important findings of this study is the nonalignment of the flux rates to the cake resistance, explained by the formation of a compressible, permeable cake layer that allowed the continuous operation of the system, under constant low pressure conditions (TMP 15 psi). Permeate flux remained constant to 120 L/m2 h when applying diafiltration, while when dewatering process is used the permeate flux remained constant at 115.4 L/m2 h.
Keywords: sludge; ceramic filter; cake resistance; flux; cross flow filtration"

The need for better nutrient management has spurred efforts towards more comprehensive recycling of nutrients contained in human excreta to agriculture. Research in this direction has intensified throughout the past years, continuously unfolding new knowledge and technologies. The present review aspires to provide a systematic synthesis of the field by providing an accessible overview of terminology, recovery pathways and treatment options, and products rendered by treatment. Our synthesis suggests that, rather than focusing on a specific recovery pathway or product and on a limited set of nutrients, there is scope for exploring how to maximize nutrient recovery by combining individual pathways and products and including a broader range of nutrients. To this end, finding ways to more effectively share and consolidate knowledge and information on recovery pathways and products would be beneficial. The present review aims to provide a template that aims to facilitate designing human excreta management for maximum nutrient recovery, and that can serve as foundation for organizing and categorizing information for more effective sharing and consolidation.

This paper presents an example of the importance of evapotranspiration in constructed wetlands, with vertical subsurface flow, comparing different methods of treatment efficiency calculations and discussing the influence of evapotranspiration on removal rates. The application of reed, marked by high transpiration ability, is a cheap and effective method of landfill leachate disposal. A 2-year study examined the effectiveness of leachate treatment in constructed wetlands with reed. Two kinds of vertical subsurface flow systems: first with sand, and second with combined two layers of sewage sludge and sand has been tested. 1, 3, and 5 mm d −1 hydraulic loading rates of landfill leachate have been applied. Daily evapotranspiration was in the range from 0.98 to 2.99 mm d −1 in the first year of research and from 2.56 to 4.61 mm d −1 in the second year. The influence of evapotranspiration rate on chemical oxygen demand (COD) removal rate was examined. Two methods of removal efficiency calculation have been used: first based on inlet and outlet COD concentrations, second on mass balance determination. Research showed that the removal efficiency calculated as a comparison between initial and final concentration is significantly lower, than expected from mass balance, especially, when higher hydraulic loading rates were applied.

The tropical ocean contains very little food or nutrients. Like life in a desert, life in the tropical ocean is difficult for all organisms. Yet, coral reefs are colorful oases full of life in the middle of this marine desert. How can millions of species call coral reefs their home? All organisms living there play their roles in recycling the small amounts of food and nutrients that are available. Because nothing is ever truly wasted, coral reefs can flourish in a marine desert that has hardly any food. Although coral reefs existed on this planet long before the dinosaurs, they are facing serious problems today. Warming oceans can harm corals, leading to the loss of coral reefs. However, corals in the northern Red Sea are very resistant to warm temperatures. Some scientists believe that these Red Sea reefs may be able to survive even when reefs are disappearing elsewhere around the world.

Experimentos de manipulação podem contribuir para a compreensão do papel ecológico da serapilheira em ecossistemas florestais. No entanto, há poucos estudos desta natureza. Os efeitos da remoção da camada de serapilheira (RS) foram avaliados sobre a comunidade de artrópodes do solo em dois plantios abandonados de Corymbia citriodora, em diferentes estágios de regeneração natural de espécies nativas de Mata Atlântica. Armadilhas de queda foram instaladas aleatoriamente em 5 parcelas (5 x 20 m) de RS e controle (CT), no plantio com 19 anos de idade (P19: estágio menos avançado; maior participação da serapilheira de eucalipto) e plantio com 42 anos (P42: estágio mais avançado de regeneração; maior participação da serapilheira de espécies nativas), nas estações chuvosa e seca, na Reserva Biológica União, RJ, Brasil. A maioria dos grupos taxonômicos apresentou inibição da abundância com a RS, no P19 e P42. De uma maneira geral, Diptera, Poduromorpha, Pseudoscorpionida, Symphypleona e larvas de Coleoptera foram os principais grupos impactados negativamente pela RS. Por outro lado, alguns grupos foram favorecidos pela RS, principalmente Entomobryomorpha e Formicidae. A RS diminuiu a riqueza total, uniformidade e diversidade de artrópodes edáficos em ambos os plantios. Contudo, este efeito negativo foi mais importante no P19, no qual também ocorreu a diminuição da abundância total e riqueza média. O maior fechamento do dossel provavelmente minimizou o impacto negativo da RS sobre os artrópodes edáficos no P42.

This work evaluated the performance of an innovative anoxic-aerobic algal-bacterial photobioreactor coupled with biogas upgrading for the treatment of domestic wastewater via nitrification-denitrification. The process, which incorporated a biomass settling step followed by recycling to the anoxic tank, was operated at a hydraulic retention time of 2 days, a sludge retention time of ≈11 days under a 12 h/12 h light/dark irradiation cycle at 392 μE m−2 * s−1. An increase in the removal efficiency of TN from 38% to 81%, NH4+ from 39% to 97%, and P-PO43− from 59% to 64% were recorded when additional CO2 was supplied to the photobioreactor via biogas scrubbing, which supported an almost complete nitrification of the NH4+ to NO3− and promoted microalgae growth (with the subsequent enhancement in N and P assimilation). TOC removal remained constant at 90 ± 2% regardless of the addition of CO2, while the effluent biomass concentration averaged 26 ± 12 mg TSS/L. A DGGE-sequencing analysis of the bacterial community revealed the occurrence of 10 phyla, Proteobacteria being the dominant phylum. Finally, the morphological characterization of the microalgae population dynamics revealed a gradual dominance of the genus Scenedesmus, which accounted for 94–100% at the end of the experiment.

A year-long series of monthly experiments with laboratory enclosures were conducted with water from Blanes Bay (NW Mediterranean) to analyse the change in the short-time response of the osmotrophic planktonic community to simulated turbulence and nutrient input events. Both experimental factors triggered a relative increase of biomass in the enclosures, in terms of chlorophyll a, bacteria and particulate organic matter. Ratios of particulate organic nitrogen to phosphorus became lower in the water than in the sediment, although turbulence partially smoothed out this difference. Initial physico-chemical conditions significantly influenced the short-time responses to experimental forcing. The response to turbulence, in terms of chlorophyll a, was maximum in spring. The response to nutrient enrichment was found to be seasonal, and was correlated with photoperiod and temperature, and also in situ nitrate and silicate concentrations and Secchi depth, which are proxies of recent inputs of nutrients resulting from episodes of resuspension and river discharge. This study shows robust qualitative regularities in the response of the osmotrophic planktonic community to episodes of turbulence and nutrient enrichment, with quantitative variability throughout the year, depending mostly on the recent record of hydrodynamic forcing.

Soil nutrient cycling in the soil-plant system of crops relies on the effects of the agronomical practices on soil conditions, especially soil microbial population mediating soil carbon transformation (either mineralization or stabilization), nitrogen cycle including soil nitrogen transformation, uptake and return from plants, and nitrogen losses, and the fate of other elements mediating these trade-offs, including phosphorous.

The lack of space and opportunity for development have been identified as key reasons behind the stagnation of the European aquaculture industry. With the historical loss and degradation of current European wetlands there is an opportunity for harnessing the commercial investment of the aquaculture industry in construction of dual purpose wetlands that incorporate both conservation and extensive aquaculture activities. These wetlands can be used to expand the area available to suitable aquaculture into ecologically sensitive areas, such as Natura 2000 sites. Veta la Palma (VLP) situated in the Doñana Natural Park (and a Natura 2000 site) is an example of such an aquaculture development and a possible model for future opportunities. In the current study some of the important ecosystem services that are provided by VLP are assessed. The provisioning services of VLP were the economic rationale for the investment and more than 820 tonnes yr-1 of fish and shrimp is produced, through a mixture of semi-extensive and extensive aquaculture. The regulating services include nutrient absorption, and the flow of river water through VLP and high primary production results in the absorption of 377 tonnes of dissolved inorganic nitrogen yr-1 , and 516 tonnes of C yr-1. Supporting services include the provision of habitat for more than 94 bird and 21 fish species. The primary production that supports the birds, extensive and semiextensive aquaculture production was also estimated to be 167,000 t, 50,000 t and 133,000 t yr-1 , respectively. The losses to birds are substantial and these estimates indicate that almost half of the primary production supports the wetland birds which directly consume 249 tonnes of fish and 2578 tonnes of invertebrates per annum. However it is the ecological credentials of the farm that enable premium prices and hence ensure the economic viability of the farm. The study demonstrates the possibility of using aquaculture to mitigate the historical loss of wetlands, provide significant ecosystem services and contribute to achievement of the European environmental legislative goals, and furthers the opportunity for the expansion of aquaculture into sensitive but impacted habitats.

Verschiedene Bioökonomie-Strategien zielen auf die Substitution fossiler Brennstoffe durch nachwachsende Rohstoffe. Jedoch ist auch die Produktion agrarischer Ressourcen im derzeitigen Modell der industriellen Landwirtschaft ein extraktives System, das auf die ständige Zufuhr externer Nährstoffe angewiesen ist. Nach einer historisch-theoretischen Analyse dieser Nährstoffflüsse geht der Beitrag auf den Nährstoff Phosphor bzw. den Rohstoff Phosphatgestein ein. Es zeigt sich, dass Phosphatgestein, jahrzehntelang eine „billige Massenware“, ab 2007 zu einem strategischen Rohstoff wurde, wobei auch Analysen über ein mögliches Fördermaximum (Peak Phosphorus) um das Jahr 2030 entstanden sind. Anhand exemplarischer Strategien staatlicher und privater Akteure zum Umgang mit der neuen Situation wird deutlich, dass die Kontrolle über Phosphor-Flüsse zunehmend umkämpft ist. Der Beitrag argumentiert, dass Bioökonomie-Strategien bereits bestehende Auseinandersetzungen um die Phosphatversorgung verschärfen und globale Ungleichheiten verstärken, die unter anderem in Ernährungskrisen hervortreten. Technologische Erneuerungen, die auch im Rahmen der Bioökonomie vorangetrieben werden, erlauben nur eine bedingte Abkehr vom extraktiven Charakter der Landwirtschaft, können aber die Interessen dominanter Akteure sichern.

Schlagwörter: Phosphatgestein, Bergbau, peak phosphorus, Düngemittel, Industrielle Landwirtschaft, Bioökonomie, Güterketten, Ernährungskrisen, Globale Ungleichheit, Brasilien, Peru, Nährstoff-Recycling

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The Extractive Basis of the Bioeconomy. Synthetic Fertilisers, Peak Phosphorus and Alternative Technologies

Abstract

Various bioeconomy strategies aim to replace fossil resources with renewable agrarian resources without departing from the agro-industrial model. Paradoxically, the bioeconomy model is an extractive system itself, dependent on the constant supply of mineral resources to replace the nutrients extracted from the soil. Using a historical-theoretical approach, this article first analyses the flows of nutrients in this system and then focuses specifically on the nutrient phosphorus and the raw material phosphate rock. Classified as a “low-cost bulk commodity” for decades, since 2007 phosphate rock has become a strategic resource and scholars have started debating the possibility of reaching “Peak Phosphorus” by 2030. By analysing state and private actor strategies to adapt to this emerging situation, it becomes clear that the control over flows of phosphorous is increasingly contested. This article argues that bioeconomy strategies are aggravating existing conflicts over phosphate supply, as well as global inequalities, which inter alia become evident in food crises. Technological innovations, which are promoted within bioeconomy strategies, only reduce the extractive character of industrial agriculture in a limited way, while also securing the interests of dominant actors.

Keywords: phosphate rock, mining, peak phosphorus, fertilizer, industrial agriculture, bioeconomy, commodity chains, food crises, global inequality, Brazil, Peru, nutrient-recycling

To examine N-isotope ratios (15 N/ 14 N) in tissues and shell organic matrix of bivalves as a proxy for natural and anthropogenic nutrient fluxes in coastal environments, Pinctada imbricata, Isognomon alatus, and Brachidontes exustus bivalves were live-collected and analyzed from eight sites in Bocas del Toro, Panama. Sites represent a variety of coastal environments, including more urbanized, uninhabited, riverine, and oceanic sites. Growth under differing environmental conditions is confirmed by δ 18 O values, with open ocean Escudo de Veraguas shells yielding the highest average δ 18 O (−1.0) value and freshwater endmember Rio Guarumo the lowest (−1.7). At all sites there is no single dominant source of organic matter contributing to bivalve δ 15 N and δ 13 C values. Bivalve δ 15 N and δ 13 C values likely represent a mixture of mangrove and seagrass N and C, although terrestrial sources cannot be ruled out. Despite hydrographic differences between end-members, we see minimal δ 15 N and δ 13 C difference between bivalves from the river-influenced Rio Guarumo site and those from the oceanic Escudo de Veraguas site, with no evidence for N from open-ocean phytoplankton in the latter. Populated sites yield relative 15 N enrichments suggestive of anthropogenic nutrient input, but low δ 15 N values overall make this interpretation equivocal. Lastly, δ 15 N values of tissue and shell organic matrix correlate significantly for pterioideans P. imbricata and I. alatus. Thus for these species, N isotope studies of historical and fossil shells should provide records of ecology of past environments.

A field experiment was conducted in the Experimental Research Farm of Omdurman Islamic University, Sudan to determine short-term effect of irrigation intervals (7 and 10 days) and sun-dried or composted sewage sludge, recommended mineral fertilizer on straw dry matter yield (SDMY) and N, P and K content of fodder sorghum and soil properties. In the 7 and 10 days irrigation intervals, composted, sun-dried sludge and mineral fertilizer have significantly increased SDMY over the control by 51, 98, 67 and 78, 19, 33%, respectively. Apparent N use efficiency (ANUE) in composted and sun dried plots irrigated at either 7 or 10 days was 9-36 and 16-74%, respectively. Reducing the irrigation interval has significantly increased salinity by 13%. Increasing irrigation interval has decreased bulk density by 5%. It could be concluded that, application of composted sludge is a useful practice for improvement of soil properties and consequent yield increase.