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The poultry industry is one of the largest and fastest growing sectors of livestock production in the world. The estimated 2010 world flock was over 18 billion birds with a yearly manure output of 22 million tonnes. Storage and disposal of raw poultry manure has become an environmental problem because of the associated air, water and soil pollution. Environmental and health problems such as odor and pathogens that may arise during and after land application of raw manure can be eliminated by drying. Dried manure can be utilized as a soil conditioner to improve soil tilth and reduce the problems associated with soil compaction and as a feed for ruminants because of its high nitrogen content. The aim of this study was to investigate the kinetics of thin layer drying of poultry manure and evaluate the effects of drying with heated air on the chemical and biological properties of manure. The effects of temperature and depth of manure layer were evaluated. The profile of the moisture content of poultry manure followed an exponential decay curve. The moisture decay constant was affected by the drying temperature and the depth of the manure layer. At the three temperature levels studied, the time required to dry poultry manure in 1 cm-deep layer was the least, followed by 2 and 3 cm-deep layers, respectively. The diffusion coefficient increased with both temperature and depth of drying layer, but did not show a linear increase with either variable. The optimum depth for drying manure (at which the highest drying effectiveness occurred) was 3 cm. Drying manure at 40-60°C resulted in the loss of 44-55% of the total Kjeldahl nitrogen, with losses increasing with both the temperature and depth of manure. The pH of the manure decreased from the initial value of 8.4 before drying to about 6.6 after drying. The odor analysis indicated that dried poultry manure did not have an offensive odor. Drying achieved 65.3 and 69.3% reductions in odor intensity and offensiveness, respectively. Reductions in the number of bacteria, mold/yeast and E.coli were 65-99, 74-99 and 99.97% respectively. The greatest reductions in microbial population occurred at the highest temperatures (60°C) and the thinest manure depths (1 cm). Heated air drying of poultry manure at temperatures between 40 and 60°C was effective in killing pathogens and removing odor.

Nature-based solutions may actively reduce hydro-meteorological risks in urban areas as a part of climate change adaptation. However, the main reason for the increasing uptake of this type of solution is their many benefits for the local inhabitants, including recreational value. Previous studies on recreational value focus on studies of existing nature sites that are often much larger than what is considered as new NBS for flood adaptation studies in urban areas. We thus prioritized studies with smaller areas and nature types suitable for urban flood adaptation and divided them into four common nature types for urban flood adaptation: sustainable urban drainage systems, city parks, nature areas and rivers. We identified 23 primary valuation studies, including both stated and revealed preference studies, and derived two value transfer functions based on meta-regression analysis on existing areas. We investigated trends between values and variables and found that for the purpose of planning of new NBS the size of NBS and population density were determining factors of recreational value. For existing NBS the maximum travelling distance may be included as well. We find that existing state-of-the-art studies overestimate the recreational with more than a factor of 4 for NBS sizes below 5 ha. Our results are valid in a European context for nature-based solutions below 250 ha and can be applied across different NBS types and sizes.

COVID-19 has changed the permeability of borders in transboundary environmental governance regimes. While borders have always been selectively permeable, the pandemic has reconfigured the nature of cross-border flows of people, natural resources, finances and technologies. This has altered the availability of spaces for enacting sustainability initiatives within and between countries. In Southeast Asia, national governments and businesses seeking to expedite economic recovery from the pandemic-induced recession have selectively re-opened borders by accelerating production and revitalizing agro-export growth. Widening regional inequities have also contributed to increased cross-border flows of illicit commodities, such as trafficked wildlife. At the same time, border restrictions under the exigencies of controlling the pandemic have led to a rolling back and scaling down of transboundary environmental agreements, regulations and programs, with important implications for environmental democracy, socio-ecological justice and sustainability. Drawing on evidence from Southeast Asia, the article assesses the policy challenges and opportunities posed by the shifting permeability of borders for organising and operationalising environmental activities at different scales of transboundary governance.

AbstractIn order to yield some insights into the planktonic food web structure of new reservoirs, size‐fractionated biomass and productivity of phytoplankton were examined from 1996 to 1997 (following the 1995 flooding of the Sep Reservoir, Puy‐de‐Dôme, France), in relation to nutrients (P, N) and metazooplankton (Rotifers, Cladocera, Copepods). Autotrophic nanoplankton (ANP, size class 3–45 μm) dominated the phytoplankton biomass (as Chlorophyll a) and production, while autotrophic picoplankton (APP, 0.7–3 μm) exhibited the lowest and relatively constant biomass and production. Cells of the autotrophic microplankton (AMP, >45 μm) were considered inedible for planktonic herbivores. The production‐biomass diagram for the different size classes and the positive correlation between APP production and ANP + AMP production suggested that grazing was potentially more important than nutrients in shaping the phytoplankton size structure. Metazooplankton biomass was low compared to other newly flooded reservoirs or to natural lakes with phytoplankton biomass similar to that of the Sep Reservoir. This resulted in low ratios (metazooplankton to edible phytoplankton) both in terms of production (average 0.43% in 1996 and 0.76% in 1997) and biomass, suggesting that only a small fraction of phytoplankton was directly consumed by metazooplankton. We suggest that the observed low ratios in the Sep Reservoir, reflect possible low metazooplankton inputs in the main influents, changes in hydrologic conditions and a high potential role of microheterotrophs. The latter role was supported by (i) the positive inter‐annual correlation between ciliates and phytoplankton, (ii) the significant and negative correlations between ciliates and metazooplankton, and (iii) the significant and negative correlations between total metazooplankton biomass and total phosphorus (TP), whereas neither TP nor total metazooplankton biomass was correlated with phytoplankton variables.

The Comcaac nation (seri) resides mainly in two towns of the State of Sonora: Desemboque and Punta Chueca. Currently, the Comcaac people face conditions of vulnerability due to the absence of water and energy. In 2020, a project with solar energy technologies was carried out in the community of Desemboque to ensure water supply and electrical energy, financed by the Honnold foundation. However, the results of this effort have not fulfilled the expectations. What happened? Through the analysis carried out by the transdisciplinary research collective, which is made up of 16 researchers from 7 institutions, national and foreign, obstacles to the development of local sustainability were identified, and the need to expand the analysis in different dimensions is recognized. This research is developed within the context of the execution of the project with funding from FORDECYT-PRONACES 315254 "Energy, water and food security for indigenous peoples in semi-arid coastal regions of Northern Mexico". (CONACYT, 2021a).

Abstract The effects of extractives, particle size, and crop species on the contents of structural carbohydrates, lignins, and micro-components in Canada Prairie Spring (CPS) wheat, durum wheat, barley, oat, and triticale straw, as well as flax shives, were determined. Extraction for 24 h in water followed by 7 h in ethyl alcohol (EtOH) yielded 20.2% extractives in triticale straw. Acid insoluble lignin decreased from 17.6% in native triticale straw to 13.6% in 24 h water + 7 h EtOH extracted triticale straw. The sample particle size influenced the values of glucan, xylan, acid insoluble lignin, ash, and extractives. Glucan, xylan, and acid insoluble lignin levels increased with increasing particle size. Protein, ash, and extractive levels decreased with increasing particle size. For flax shives, glucan, xylan, and acid insoluble lignin levels increased with increasing particle size from 19.1% to 33.2%, from 6.7% to 18.8%, and from 17.4% to 25.7%, respectively. The protein, ash, and extractive levels in flax shives decreased with increasing particle size from 6.5% to 1.9%, from 27.7% to 0.9%, and from 15.0% to 3.8%, respectively. Total glycans, lignin and extractive levels for the various straws, from the medium particle sized fraction, were 56.6–63.9, 14.7–19.4, and 6.8–20.2%, respectively. Total glycans, lignin, and extractives levels from the medium particle sized flax shives were 51.8, 25.8, and 6.46%, respectively. The composition of the medium particle size fraction reflected the composition of the corresponding original sample.

A life cycle analysis (LCA) for pyrolysis biochar systems was carried out to determine greenhouse gas balance, carbon cycling, and the economics of biochar production from different agricultural residues and wastes. Investigating a range of feedstocks (forest residues, corn stover, etc.) provided insight into the use of biomass residues rather than bioenergy crops as biochar production substrates and the resulting energy and climate change impacts. The analyses were conducted based on various optimized pyrolysis parameters for corn fodder and forest residue. The observed reductions of greenhouse gas (GHG) emissions (CO2 equivalent per Mg dry feedstock) for both corn fodder and forest residue were mainly contributed by the stable carbon in the biochar. Corn fodder showed a greater reduction in emissions than forest residue, indicating the corn fodder’s greater economic potential for soil sequestration of stable carbon. The relative GHG emission analysis found that the optimization of a biomass pyrolysis system for biochar production is better suited for soil sequestration of stable carbon than as a fuel source. The economic viability of the pyrolysis-biochar system is largely dependent on the costs of feedstock production, pyrolysis, and the value of C offsets. The LCA reported in this study can be instrumental in assessing the environmental potential of biochar production and its application in the region.

Abstract In-woods torrefaction of forest residues to produce biochar can sequester CO2 in long-lived products at potentially lower-cost and complexity than centralized biochar production. Yet there are major uncertainties around operations, cost, and emissions associated with in-woods processing. We present a technoeconomic and emissions analysis for mobile in-woods biochar production systems employing oxidative torrefaction, associated with a timber harvest in Jackson Demonstration State Forest (JDSF) of California as case study. Most of the processing site area is required for the pile of grinded slash feed and drying operations. Breakeven production costs for transport, processing, and application together range between 567 and 573 USD/ton biochar-C (equivalent to 392–341 USD/ton biochar). The dryer, if employed, and the reactor constitute the major portion of capital costs. Labor constitute the largest portion of operating costs, followed by tub grinder rental and biochar application within the forest soil. The requirement of a separate dryer can be relaxed for a mobile in-woods facility, as oxidative torrefaction provides the opportunity to process feedstock with relatively high moisture content (~50%). The respective net GHG emissions for two systems with and without dryer are 5.43 and 7.94 ton CO2 eq/ton biochar-C. However, when the emissions from natural decay of slash (if left unprocessed) are accounted as avoided emissions, the systems with and without dryer result in the respective GHG emission benefits of 6.61 and 4.85 ton CO2 eq/ton biochar-C. The systems reach their break-even point when CO2 emission benefits are valued at a minimum of 85.7–118.1 USD/ton CO2.