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21.
Malodor emissions limit public acceptance of using municipal biosolids as natural organic resources in agricultural production. We aimed to identify major odorants and to evaluate odor concentrations associated with land application of anaerobically digested sewage sludges (Class B) and their alkaline (lime and coal fly ash)-stabilized products (Class A). These two types of biosolids were applied at 12.6 tonnes ha(-1) (dry weight) to microplots of very fine clayey Vertisol in the Jezreel Valley, northern Israel. The volatile organic compounds (VOCs) emitted from the biosolids before and during alkaline stabilization and after incorporation into the soil were analyzed by headspace solid-phase microextraction followed by gas chromatography-mass spectrometry. Odor concentrations at the plots were evaluated on site with a Nasal Ranger field olfactometer that sniffed over a defined land surface area through a static chamber. The odors emitted by anaerobically digested sewage sludges from three activated sludge water treatment plants had one characteristic chemical fingerprint. Alkaline stabilization emitted substantial odors associated with high concentrations of ammonia and release of nitrogen-containing VOCs and did not effectively reduce the potential odor annoyance. Odorous VOCs could be generated within the soil after biosolids incorporation, presumably because of anaerobic conditions within soil-biosolids aggregates. We propose that dimethyl disulfide and dimethyl trisulfide, which seem to be most related to the odor concentrations of biosolids-treated soil, be used as potential chemical markers for the odor annoyance associated with incorporation of anaerobically digested sewage sludges.  相似文献   
22.
Nowadays there are approximately 80 Anglophone journals that deal primarily with disaster risk reduction (DRR) and allied fields. This large array signals a sustained, if uneven, growth in DRR scholarship but also competition between the offerings of different publishers and institutions. The purpose of this article is first to summarise the development of academic publishing on DRR from its early beginnings to the present day. The paper then evaluates the current state of publishing in this field and discusses possible future trends. Next, it identifies some possible opportunities, challenges, expectations, and commitments for journal editors both within DRR and academia more broadly, including those that refer to changes in the use of terminology, the relentless increase in the number of papers submitted, the expansion and dangers of predatory journals, different peer review models, open access versus paywalls, citations and bibliography metrics, academic social networks, and copyright and distribution issues.  相似文献   
23.
Measurements of the photosynthetic activity of symbiotic zooxanthellae in corals under natural growth conditions has been limited until recently, and this is one of the first reports on utilising a newly developed underwater pulse amplitude modulated (PAM) fluorometer (the Diving-PAM, Walz Gmbh, Germany) for such studies in situ. Photosynthetic responses to irradiance (photosynthetic photon flux, PPF) of the two faviid corals Favia favus (Forskål) and Platygyra lamellina (Ehrenberg) were measured while snorkelling or SCUBA diving (in August 1997), and we report here the results in terms of effective quantum yields of photosystem II (Y?) and estimated rates of photosynthetic electron transport (ETR, calculated as Y?×?0.5?× PPF?×?FA, where FA is the estimated fraction of light absorbed by the photosymbiont-containing tissue). Both species showed a reduction in Y with increasing actinic irradiances produced by the instrument above 500?μmol photons m?2 s?1, and the corresponding ETR values yielded apparently typical photosynthesis versus irradiance (P-I?) curves, which saturated between 1500 and 2000?μmol photons m?2 s?1. It was found that 30?s irradiation at each PPF level was sufficient to give optimal ETR values and, therefore, each P-I curve could be obtained within a few minutes. In situ point measurements from various areas of colonies under ambient light showed average ETR values within the range expected from the P-I curves. In order to test the Diving-PAM in an eco-physiologically relevant experiment, photosynthetic ETR versus PPF was measured for three sections of a large P. lamellina, each section of which received different natural irradiance levels. The results clearly demonstrated adaptations to the ambient light field in that vertical and downward-facing portions of the colony showed gradually lower maximal ETRs, steeper initial slopes of the P-I curves and, accordingly, lower light saturation points than upward-facing areas receiving higher light levels. Based on these trials, some evaluations are given as to the applicability of the Diving-PAM for photosynthetic measurements when monitoring similar corals.  相似文献   
24.
In this study eight different species of barnacles were found within nine species of sponges from the Red Sea. This brings to 11 the number of sponge-symbiotic barnacles reported from the Red Sea, two of these are new Acasta species (not described herein) and one (A. tzetlini Kolbasov) is a new record for this sea. This number is much higher than that of symbiotic barnacles found within sponges from either the N. Atlantic (2) or the Mediterranean (4). Two possible explanations for this are the presence of numerous predators in coral reefs and scarcity of available substrate for settlement. These factors can lead to high incidence of symbiotic relationships. Of the nine sponge species, only one (Suberites cf. clavatus) had previously been known to contain barnacles. Even at the family level, this is the first record of symbiotic barnacles in two out of the seven sponge families (Latrunculiidae, Theonellidae). Our present findings strengthen the apparent rule that the wider the openings in a barnacle shell, the fewer the host taxa with which it will associate, usually from one or two closely related families, and the more frequent it will associate with elastic sponges. Most Neoacasta laevigata found on Carteriospongia foliascens were located on the same side as the sponge's ostia, i.e. facing the incoming water. This adaptation allows the barnacles to catch more suspended particles from the water, provides them with more oxygen and prevents their exposure to discharged sponge waste. The highest density of barnacles observed on one face of a “leaf ” (with ostia) was 0.389 barnacles cm−2 (one barnacle per 2.57 cm2) and on average 0.181 ± 0.68, while the average on the other side was only 0.068 ± 0.52 barnacles cm−2. As indicated by the Morisita index, these barnacles most frequently (58%, n = 12) had a clumped spatial distribution (while the rest were randomly distributed), as is to be expected from such sessile organisms with internal fertilization via copulation. The presence of N. laevigata induced the growth of secondary perpendicular projections of its host C. foliascens. Of the N. laevigata examined, 17% brooded 324 ± 41 embryos each, of 286 ± 17 μm total length; only 5.7% (n = 123) were found to be dead. Size distribution analysis of skeletal elements from dead barnacles showed them to be significantly larger than the skeletal elements of the population of live barnacles ( p < 0.05). Received: 26 June 1998 / Accepted: 1 December 1998  相似文献   
25.
The knowledge produced by conservation scientists must be actionable in order to address urgent conservation challenges. To understand the process of creating actionable science, we interviewed 71 conservation scientists who had participated in 1 of 3 fellowship programs focused on training scientists to become agents of change. Using a grounded theory approach, we identified 16 activities that these researchers employed to make their scientific products more actionable. Some activities were more common than others and, arguably, more foundational. We organized these activities into 3 nested categories (motivations, strategies, and tactics). Using a co-occurrence matrix, we found that most activities were positively correlated. These correlations allowed us to identify 5 approaches, framed as profiles, to actionable science: the discloser, focused on open access; the educator, focused on science communication; the networker, focused on user needs and building relationships; the collaborator, focused on boundary spanning; and the pluralist, focused on knowledge coproduction resulting in valuable outcomes for all parties. These profiles build on one another in a hierarchy determined by their complexity and level of engagement, their potential to support actionable science, and their proximity to ideal coproduction with knowledge users. Our results provide clear guidance for conservation scientists to generate actionable science to address the global biodiversity conservation challenge.  相似文献   
26.
Lee  Eunjee  Livino  Angela  Han  Shin-Chan  Zhang  Ke  Briscoe  John  Kelman  Jerson  Moorcroft  Paul 《Regional Environmental Change》2018,18(6):1871-1881
Regional Environmental Change - Over the past 40&nbsp;years, the discharge in South America’s Paraná River basin has increased despite no evidence of significant rainfall increases...  相似文献   
27.
Olga Filippova  Ilan Noy 《Disasters》2020,44(1):179-204
New Zealand introduced a seismic retrofitting policy in the wake of the catastrophic Canterbury earthquakes of 2010–11. The aim was to enforce seismic strengthening of earthquake-prone commercial buildings throughout the country. This study focuses on regional urban centres and the economic obstacles to strengthening their aging building stock. In investigating one town, Whanganui, we describe conditions, analyse cases, and identify incentives that apply equally to many other towns in New Zealand. We argue that incentives that suit high-growth, high-value major urban centres are a poor fit for the periphery. Around the world, many places need to upgrade their privately-owned building stock to protect it from disasters, while governments face similar challenges as they struggle to initiate the strengthening of commercial buildings. We analyse the current incentive schemes that aim to support the achievement of policy goals and suggest alternative incentive schemes that can be implemented to improve strengthening outcomes.  相似文献   
28.
M. Ilan  Y. Loya 《Marine Biology》1990,105(1):25-31
Characteristics of the sexual reproduction and larval settlement of the haplosclerid spongeChalinula sp., which inhabits the shallow waters (1 to 6 m) of Eilat, Red Sea, were investigated from September 1985 through to November 1987. This species was found to be a simultaneous hermaphroditic brooder, hence gonochorism is not the rule in the order Haplosclerida. Brooding always takes place in special brooding chambers. While the oocytes in the brooding chambers are among the largest known in sponges (355±37µm), the spermatic cysts distributed in the choanosome are among the smallest known for this phylum (average 26±7µm).Chalinula sp. breeds throughout the year and in experiments most larvae (74%) settled within 1 to 8 h post-release, generally within 4.5 h. Metamorphosis from larval shape to a sessile sponge lasts 1 to 6 h. Thus, larvae had a short swimming period, settled fast, and metamorphosed rapidly (within 1 to 6 h). The large size of the larvae may contribute to their ability to rapidly reorganize their body shape into that of a sessile sponge. In addition, the existence of already differentiated choanocyte chambers in the larvae, facilitates fast construction of the water filtration system in the newly settled sponges. The reproductive and larval characteristics ofChalinula sp. enable the larvae to settle on any vacant space in the reef, which may explain its abundance in the Red Sea.  相似文献   
29.
With shrinking forest resources and increasing demands for timber, conflicts between forestry and wildlife become more contentious and more frequent. New decision support methods are needed to address complex multiple land use conflicts. Multiple accounts methods linked with GIS and production models enable us to address trade-offs between timber and non-timber values, thus facilitating the evaluation and comparison of different management scenarios in a rapid and spatially referenced manner. The approach is documented in a case study in the trans-boundary zone between two national parks in British Columbia, where caribou/logging conflicts are widespread.  相似文献   
30.
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