造纸污泥工厂化堆肥过程中理化性质的动态变化

工厂化强制通风静态垛好氧堆肥试验结果表明,造纸污泥与木屑按10∶1比例混合后,2~3 d即可达到60℃,高温期维持时间超过10 d,完全符合我国标准CJJ/T52-93规定,达到无害化要求;堆肥过程中堆体上层温度大于下层;高温堆肥后物料含水率降低20.2%,脱水效果明显;造纸污泥堆肥过程中物料的挥发性固体持续降低;堆体耗氧速率在升温阶段后期上升到最大值,此后持续降低,到堆肥后期趋于稳定。     

复合添加剂对污泥堆肥化重金属形态及生物有效性的影响

通过添加不同比例粉煤灰(0%、5%、15%、25%、35%)和生石灰(0%、1%)进行污泥堆肥试验,并将堆肥产品应用于玉米幼苗盆栽试验,研究不同处理对污泥堆肥产品重金属(Zn、Cu、Cd、Ni)形态分布和生物有效性的影响。研究结果可为粉煤灰和生石灰复合添加剂在城市污泥堆肥中的应用提供基础资料和科学依据。结果表明,(1)污泥堆肥过程中,p H值整体呈现上升-稳定下降-稳定的变化规律,重金属Zn、Cu、Cd、Ni含量因稀释效应呈现轻微下降;添加35%粉煤灰和1%生石灰处理,重金属Zn、Cu、Cd、Ni含量达到最小值,分别为611.20、226.18、1.49、68.74 mg?kg~(-1)。(2)Zn、Cd、Ni主要以残渣态形式存在,Cu主要以有机结合态形式存在。随着粉煤灰添加量增加,残渣态、有机结合态、铁锰氧化态Zn、Cd和残渣态、有机结合态Ni含量逐渐增大,交换态、碳酸盐态Zn、Cd、Ni含量逐渐减小,重金属生物有效性下降。(3)施用添加25%粉煤灰和1%生石灰的污泥肥料后,玉米地上部分干重最大为21.2 g,玉米重金属Zn、Cu、Ni、Cd含量均达到最小值19.44、13.73、0.08、0.45 mg?kg~(-1),基质重金属Zn、Ni分别达到最小值79.44、0.75 mg?kg~(-1)。以上结果说明,添加粉煤灰和生石灰进行污泥堆肥化对重金属总量影响不大,但能有效改变重金属形态,降低重金属生物有效性。其中,添加25%粉煤灰与1%生石灰污泥堆肥产品,有利于重金属由不稳定态转变成稳定态,也最有利于玉米幼苗生长。     

蚯蚓-稻壳炭联合堆肥对工业污泥中重金属的影响研究

蚯蚓堆肥相关研究多集中在生活污泥方面,对工业污泥的探索较少。该研究以马鞍山某钢铁污水处理站污泥为例,添加不同比例稻壳炭(2%、4%、8%),设置污泥单独堆肥、稻壳炭与污泥堆肥以及蚯蚓-稻壳炭联合污泥堆肥试验,探索蚯蚓与稻壳炭联合堆肥对工业污泥中重金属形态和生物有效性的影响。研究表明,(1)相比污泥单独堆肥,稻壳炭联合污泥堆肥能增加污泥pH、EC、TP和降低TOC、TN,而蚯蚓联合稻壳炭堆肥污泥可增加TN,并进一步增加污泥EC、TP,显著降低污泥的pH、TOC。(2)稻壳炭堆肥中重金属Zn、Cu、Pb、Cd含量因浓缩效应而上升;而蚯蚓联合稻壳炭堆肥,重金属含量显著下降,添加4%稻壳炭时,重金属Zn、Cu、Pb、Cd质量分数达到最小值,分别为856.64、137.10、158.92、15.48mg·kg-1。(3)重金属形态分析表明,随着稻壳炭比例增加,稻壳炭堆肥中重金属Zn、Cu、Pb、Cd的交换态和碳酸盐结合态转化为残渣态及铁锰氧化态的比例增大,添加8%稻壳炭时DTPA提取的有效态重金属质量分数最低,分别为705.72、47.95、50.43、4.47 mg·kg-1;蚯蚓-稻壳炭联合堆肥会使得污泥中重金属交换态、碳酸盐结合态、铁锰结合态和有机结合态均向残渣态转化,添加4%稻壳炭与蚯蚓的协同转化能力最大,Zn、Cu、Pb、Cd有效态重金属质量分数分别为629.84、38.63、36.76、1.63mg·kg-1,说明稻壳炭添加入蚯蚓堆肥可进一步降低工业污泥中重金属有效性,使重金属钝化。本研究可为稻壳炭联合蚯蚓堆肥处理工业污泥提供参考和科学依据。     

城市污泥好氧堆肥过程中重金属的形态转化

城市污泥是一种富含作物生长需要的多种养分的生物固体废弃物,但重金属问题又成为影响污泥农用的关键因素,而重金属的生物活性、迁移性及毒性不仅取决于总量,很大程度上取决于其存在的形态.该实验通过调节城市污泥的水分和C/N比,利用笔者所在课题组自行开发的好氧堆肥反应器进行城市污泥堆肥处理,经过为期20 d的好氧堆肥处理,研究堆肥前后污泥中的重金属总量和化学形态的变化.实验结果表明:堆肥处理由于添加能源调理剂等,使堆肥产品中的重金属含量低于原污泥,符合了农用污泥污染物控制标准;同时堆肥也改变了重金属的化学形态,降低了剧毒性的Cd的生物有效性.对污泥及堆肥的重金属形态研究发现:大部分重金属主要以残渣态形式存在,生物毒性很小,农用时的重金属污染度也很低.     

粪渣污泥好氧堆肥过程中主要理化性质的动态变化

进行了粪渣污泥的强制通风静态垛堆肥试验,分析了温度、氧气、含水率和挥发性有机物在堆肥不同阶段的变化特征。粪渣与木屑质量1∶1.5的比例下,能够实现快速高温好氧堆肥,堆体温度在高温期持续9d,达到无害化的卫生学要求。堆体耗氧速率在升温阶段后期上升到最大值,此后持续降低,到堆肥后期趋于稳定。据此提出了相应的通风策略。在堆肥过程中,物料的含水率和挥发性有机物含量持续降低,但到堆肥后期趋于稳定,堆肥结束时分别减小17个百分点和10.4个百分点。     

堆肥过程中腐殖质含量变化及其对重金属分配的影响

以H2O和Na4P2O7+NaOH连续浸提污泥堆肥过程中堆体的腐殖酸以及与其结合的重金属,分析腐殖酸及重金属含量随时间的变化规律。结果表明,堆肥过程中重金属主要以胡敏酸(HA)结合态为主,水溶态重金属含量较少,且重金属有效性与迁移性较低;堆肥结束时各水溶态重金属含量减少,HA-Pb、HA-Ni和HA-Cu含量占重金属总量的比例明显升高,与堆肥初始相比分别增加28.00、17.34和1.40百分点,堆肥促进了水溶态重金属向HA结合态转变;HA对几种重金属的固定能力由大到小依次为Cu、Pb、Ni和Zn。     

新型调理剂CTB-2污泥堆肥的氧气时空变化特征研究

采用新型CTB-2调理剂与城市污泥进行堆肥,研究了堆肥过程中氧气、温度的时空变化特征。结果表明,m（CTB-2调理剂）：m（污泥）=1：2能够有效降低污泥容重,改善堆体结构;堆体能够快速升温至高温期并持续7d以上,最终完成无害化;采用该比例的调理剂能够保证堆体的通风供氧,使堆体各层通风后的氧气体积分数都恢复至19％以上,最低氧气体积分数维持在数17％以上;堆肥过程中堆体的氧气体积分数、耗氧速率和温度都具有明显的层次效应,堆体耗氧速率呈先升高后降低的趋势,堆体通风后的氧气和最低氧气体积分数均随着堆肥的进行而增加。     

磷酸盐添加对快速好氧堆肥过程pH及腐熟效果的影响

随着我国环保政策的日趋严格,具有堆肥周期短、产品质量好、二次污染小等优点的反应器快速好氧堆肥工艺受到人们的广泛关注.然而,由于堆肥原料的有机物含量高,导致快速堆肥初期的有机酸累积,堆体pH偏低,影响堆肥效果.本研究拟通过添加磷酸盐,解决剩余污泥反应器快速堆肥过程出现的pH偏低问题.结果表明,添加磷酸盐可有效控制堆体pH,堆肥初期,HPO_4~-通过与有机酸解离产生的H~+反应生成H_2PO~-_4,提高堆体pH,堆肥后期,蛋白质降解产生较多NH~+_4,导致pH升高,堆体中的H_2PO~-_4通过与OH~-结合生成HPO_4~-,降低堆体pH.当HPO_4~-与H_2PO~-_4的摩尔比为2∶5时,堆体pH值可维持在6.0—8.5之间,有机物降解率最高,堆体的NH~+_4-N含量最大,达3.99 mg·g~(-1),堆肥过程的保氮效果较好,且所得堆肥产品的种子发芽指数也较高,腐熟程度良好.     

污泥堆肥过程中主要性质及氮素转变

目前堆肥过程中氮素损失比较严重,通常达到50%左右.针对这一问题,文章以污泥和秸秆为原料,进行了不同配比条件下高温好氧堆肥试验,研究了堆肥过程中各主要性质及各种形态氮素的转化规律.结果表明,堆肥有效实现了污泥无害化、减量化和资源化.在pH值和温度较高条件下的氨气大量挥发是堆肥过程氮素损失的重要途径,且不同的物料配比会对氮素损失造成影响,C/N比低的配比氮素损失较大.适当降低堆料温度、添加酸性物质以降低pH值等措施均可减少氮素损失.     

腐熟堆肥接种对蔬菜废物中高温好氧降解过程的影响

通过不同比例腐熟堆肥接种,进行蔬菜废物高温好氧降解试验,研究接种对蔬菜废物好氧降解过程的影响.结果表明:当接种率为5%,3%和1%时,增加腐熟堆肥接种比例有利于提高有机物的好氧降解率,试验末期有机物降解率分别为53.3%,50.0%和43.7%,糖类和纤维素类降解的差别是其降解率差距的主要来源;腐熟堆肥接种对堆肥过程中微生物演化规律影响明显,但接种率达到一定水平后,接种对生物相的影响会随堆肥过程而逐步消失;通过对微生物相演变与生物质降解过程的相关性分析,表明微生物种群增殖与特定生物质类型降解存在明显的相关性,从而提示了采用按堆肥过程中生物质分类的降解状况分段接种微生物的可能性.     

Achieving Open Access to Conservation Science

Conservation science is a crisis discipline in which the results of scientific enquiry must be made available quickly to those implementing management. We assessed the extent to which scientific research published since the year 2000 in 20 conservation science journals is publicly available. Of the 19,207 papers published, 1,667 (8.68%) are freely downloadable from an official repository. Moreover, only 938 papers (4.88%) meet the standard definition of open access in which material can be freely reused providing attribution to the authors is given. This compares poorly with a comparable set of 20 evolutionary biology journals, where 31.93% of papers are freely downloadable and 7.49% are open access. Seventeen of the 20 conservation journals offer an open access option, but fewer than 5% of the papers are available through open access. The cost of accessing the full body of conservation science runs into tens of thousands of dollars per year for institutional subscribers, and many conservation practitioners cannot access pay‐per‐view science through their workplace. However, important initiatives such as Research4Life are making science available to organizations in developing countries. We urge authors of conservation science to pay for open access on a per‐article basis or to choose publication in open access journals, taking care to ensure the license allows reuse for any purpose providing attribution is given. Currently, it would cost $51 million to make all conservation science published since 2000 freely available by paying the open access fees currently levied to authors. Publishers of conservation journals might consider more cost effective models for open access and conservation‐oriented organizations running journals could consider a broader range of options for open access to nonmembers such as sponsorship of open access via membership fees. Obtención de Acceso Abierto a la Ciencia de la Conservación     

Representation of the world's biophysical conditions by the global protected area network

Protected areas (PAs) are often implemented without consideration of already existing PAs, which is likely to cause an overrepresentation of certain biophysical conditions. We assessed the representativeness of the current PA network with regard to the world's biophysical conditions to highlight which conditions are underprotected and where these conditions are located. We overlaid terrestrial and marine PAs with information on biophysical conditions (e.g., temperature, precipitation, and elevation) and then quantified the percentage of area covered by the PA network. For 1 variable at a time in the terrestrial realm, high temperature, low precipitation, and medium and very high elevation were underrepresented. For the marine realm, low and medium sea surface temperature (SST), medium and high sea surface salinity (SSS), and the deep sea were underrepresented. Overall, protection was evenly distributed for elevation across the terrestrial realm and SST across the marine realm. For 2 variables at a time, cold and very dry terrestrial environments had mostly low protection, which was also the case for low SST and low and medium SSS across most depths for marine environments. Low protection occurred mostly in the Sahara and the Arabian Peninsula for the terrestrial realm and along the Tropic of Capricorn and toward the poles for the marine realm. Although biodiversity measures are of prime importance for the design of PA networks, highlighting biophysical gaps in current PAs adds a frequently overlooked perspective. These gaps may weaken the potential of PAs to conserve biodiversity. Thus, our results may provide useful insights for researchers, practitioners, and policy makers to establish a more comprehensive global PA network.     

Quantitative composition of the defensive secretion ofBledius species (Coleoptera: Staphylinidae: Oxytelinae) is adapted to naturally occurring predators

Summary The adaptation of defensive secretions to their target organisms was examined for the abdominal gland secretions ofBledius furcatus, B. spectabilis andB. arenarius. Therefore the target organisms of the secretion of theseBledius species (i.e. their predators) had to be identified. At the collection sites examined these were the earwigLabidura riparia, the antCataglyphis bicolor, the flyLispe candicans, different carabids of the generaPogonus, Dichirotrichus, Dyschirius, Bembidion andCalathus and the wading birdsHaematopus ostralegus andCalidris alba. The secretion of the abdominal glands contains the toxin ptoluquinone dissolved in either-dodecalactone and 1-undecene (B. furcatus andB. spectabilis) or in octanoic acid and octyloctanoate (B. arenarius). The ratio of these solvents is species-specific. Application experiments using some of the natural insect predators (L. riparia, C. bicolor, Pogonus, Di. gustavii, Dyschirius) revealed that these solvent ratios provided a more effective deterrent than other possible ratios. Thus by combining the solvents in certain ratios, the capability of cuticular penetration and therefore the effectiveness of the defensive secretions are adapted to their natural targets.     

Democracy versus development: New urban debates

The politics of development includes subtexts of choice, as underpinned by community consensus (or lack of it), against the larger backdrop of a liberal democracy, with its intricate power structures that influence the choice of concepts and often lead to complicity rather than consent. A dilemma exists between the understanding of field-level practitioners and that of academics, whose understandings of progress differ. Progress can (and often does) imply long-term change across generations whereas development is often more a matter of crisis management and delivering tangible results to end-users. This makes it a bone of contention across political systems, irrespective of local or global dynamics. Development can emerge as a tool to be wielded for power and further political mileage at the expense of progress. Progress cannot be studied as a counterpoint to development as the sense of history is often missing in development interventions. Development tends to be piecemeal as its very logic often stems from the rationale of power. This is not to suggest, however, that development is only about politics; it is definitely more than the politics of everyday life and involves all of civil society that requires its critical and immediate attention. In this sense, it has become a priority for politicians with an underlying agenda designed to out-manouevre dissent and all statements of protest.     

A framework to measure the wildness of managed large vertebrate populations

As landscapes continue to fall under human influence through habitat loss and fragmentation, fencing is increasingly being used to mitigate anthropogenic threats and enhance the commercial value of wildlife. Subsequent intensification of management potentially erodes wildness by disembodying populations from landscape-level processes, thereby disconnecting species from natural selection. Tools are needed to measure the degree to which populations of large vertebrate species in formally protected and privately owned wildlife areas are self-sustaining and free to adapt. We devised a framework to measure such wildness based on 6 attributes relating to the evolutionary and ecological dynamics of vertebrates (space, disease and parasite resistance, exposure to predation, exposure to limitations and fluctuations of food and water supply, and reproduction). For each attribute, we set empirical, species-specific thresholds between 5 wildness states based on quantifiable management interventions. We analysed data from 205 private wildlife properties with management objectives spanning ecotourism to consumptive utilization to test the framework on 6 herbivore species representing a range of conservation statuses and commercial values. Wildness scores among species differed significantly, and the proportion of populations identified as wild ranged from 12% to 84%, which indicates the tool detected site-scale differences both among populations of different species and populations of the same species under different management regimes. By quantifying wildness, this framework provides practitioners with standardized measurement units that link biodiversity with the sustainable use of wildlife. Applications include informing species management plans at local scales; standardizing the inclusion of managed populations in red-list assessments; and providing a platform for certification and regulation of wildlife-based economies. Applying this framework may help embed wildness as a normative value in policy and mitigate the shifting baseline of what it means to truly conserve a species.     

Some polyphagous Homoptera gain protection from their natural enemies by feeding on the toxic plantsSpartium junceum andErythrina corallodendrum (Leguminosae)

Summary Interactions were studied among alkaloid-containing legumes (Erythrina corallodendrum andSpartium junceum) and non-toxic plants (Citrus sinensis, Cucurbita moschata andEuphorbia tirucalli), several polyphagous homopterans,Aphis craccivora (Aphididae),Icerya purchasi, I. aegyptiaca (Margarodidae),Lepidosaphes ulmi (Diaspididae) andPlanococcus citri (Pseudococcidae), and some major natural enemies of these homopterans. Significant reductions in survival due to negative effects of alkaloid containing as compared with non-alkaloidal plants were recorded for the predatorsRodolia cardinalis andChilocorus bipustulatus, but not forCryptolaemus montrouzieri (Coleoptera: Coccinellidae),Chrysoperla carnea (Neuroptera: Chrysopidae) andSympherobius sanctus (Neuroptera: Sympherobiidae). The development time of the larvae or pupae ofR. cardinalis, C. carnea andS. sanctus was longer on the toxic plants than on the non-toxic ones. The percentage of parasitism ofA. craccivora collected from the non-alkaloidal plantsVicia palaestina andMelilotus albus was much higher than that onS. junceum. The parasitoid complexes ofA. craccivora differed between both plant groups. The nutritive value of honeydew ofI. purchasi andA. craccivora, as expressed by the life span ofEncyrtus infelix (Hymenoptera: Encyrtidae) adults, was also investigated. Life spans were significantly longer when the wasps fed on honeydew produced on non-alkaloidal plants (C. sinensis andPittosporum tobira) than on alkaloid containing plants whenI. purchasi — but notA. craccivora — was the producer. It is suggested that the chemical defense ofE. corallodendrum andS. junceum is exploited by polyphagous phytophages to reduce predation. In nature, population growth and density of four of the investigated homopterans are conspicuously high when they developed on the alkaloid containing plant species, and very low on non-alkaloid plants. The efficiency of their natural enemies may be reduced by sequestration of alkaloids (or other toxic plant compounds) or their transfer into excreted honeydew. Therefore it is assumed that a generalist phytophagous homopteran may be protected from its natural enemies, although at different rates of efficiency, if it can safely sequester the host allelochemical when it develops on toxic species within its host range.     

Sexual Predators,Energy Development,and Conservation in Greater Yellowstone

Abstract: In the United States, as elsewhere, a growing debate pits national energy policy and homeland security against biological conservation. In rural communities the extraction of fossil fuels is often encouraged because of the employment opportunities it offers, although the concomitant itinerant workforce is often associated with increased wildlife poaching. We explored possible positive and negative factors associated with energy extraction in the Greater Yellowstone Ecosystem (GYE), an area known for its national parks, intact biological diversity, and some of the New World's longest terrestrial migrations. Specifically, we asked whether counties with different economies—recreation (ski), agrarian (ranching or farming), and energy extractive (petroleum)—differed in healthcare (gauged by the abundance of hospital beds) and in the frequency of sexual predators. The absolute and relative frequency of registered sex offenders grew approximately two to three times faster in areas reliant on energy extraction. Healthcare among counties did not differ. The strong conflation of community dishevel, as reflected by in‐migrant sexual predators, and ecological decay in Greater Yellowstone is consistent with patterns seen in similar systems from Ecuador to northern Canada, where social and environmental disarray exist around energy boomtowns. In our case, that groups (albeit with different aims) mobilized campaigns to help maintain the quality of rural livelihoods by protecting open space is a positive sign that conservation can matter, especially in the face of rampant and poorly executed energy extraction projects. Our findings further suggest that the public and industry need stronger regulatory action to instill greater vigilance when and where social factors and land conversion impact biological systems.     

Comparison of the insecticidal effects of water extracted and intact aromatic plants onAcanthoscelides obtectus,a bruchid beetle pest of kidney beans

Summary Acanthoscelides obtectus (Say) is one of the most damaging pests of kidney beans,Phaseolus vulgaris L. worldwide. However, aromatic plants from the families Lamiaceae, Lauraceae, Myrtaceae and Poaceae can protect kidney beans by direct or delayed insecticidal effect, through increased adult mortality and inhibition of beetle reproduction (both oviposition and adult emergence). The efficiency of hydrodistillated and intact plants fromThymus vulgaris andT. serpyllum, Mentha piperata, Rosmarinus officinalis, Satureia hortensis, Eucalyptus globulus, Laurus nobilis, Origanum vulgare, andCymbopogon nardus was compared. For both extracts,Origanum vulgare had the best effect. The insecticidal effect was induced by more than the essential oils because no significant difference was noticed between distilled and intact plants extract. Inhibition of reproduction was particularly important. These results suggest that lipidic as well as non lipidic, allelochemicals, such as phenolics, or non-protein amino-acids, or flavonoids may be involved in the toxicity of aromatic plants to this beetle.     

Rapid,recurring, structured survey versus bioblitz for generating biodiversity data and analysis with a multispecies abundance model

A bioblitz inexpensively and quickly generates biodiversity data, but bioblitzes are often conducted with haphazard, unreplicated sampling. Results tend to be taxonomically, geographically, or temporally biased, lack metadata, and consist of lists of observed taxa that do not enable further analyses or correction for imperfect detection. A rapid, recurring, structured survey (RRSS) uses a structured sampling design and temporal and spatial replication to survey randomly selected sites on a conservation property. We participated in a loosely structured bioblitz and a subsequent RRSS at Big Canoe Creek Nature Preserve in Springville (St. Clair County), Alabama (USA) to compare observed richness derived from the 2 survey approaches. The RRSS data structure enabled us to fit models that accounted for imperfect detection to estimate abundances, occupancy probabilities, and habitat associations. The loosely structured bioblitz data could not be used in such models. We present a new integrated multispecies abundance model that we applied to avian RRSS data. Our model extension enables estimation for the community, employs data augmentation to estimate the number of undetected species, and incorporates covariates. The RRSS generated a more comprehensive and less biased list of observed taxonomic richness than the loosely structured bioblitz (e.g., 73 vs. 45 bird species and 104 vs. 63 insect families from the RRSS vs. loosely structured bioblitz, respectively). Models fit to the RRSS data identified seasonal patterns in avian community composition and allowed for estimation of habitat–occupancy relationships for insect taxa. The RRSS protocol has potential for broad transferability as a standardized, quick, and inexpensive way to inventory biodiversity and estimate ecological parameters while providing an outreach opportunity.     

Compliance with and ecosystem function of biodiversity offsets in North American and European freshwaters

Land-use change via human development is a major driver of biodiversity loss. To reduce these impacts, billions of dollars are spent on biodiversity offsets. However, studies evaluating offset project effectiveness that examine components such as the overall compliance and function of projects remain rare. We reviewed 577 offsetting projects in freshwater ecosystems that included the metrics project size, type of aquatic system (e.g., wetland and creek), offsetting measure (e.g., enhancement, restoration, and creation), and an assessment of the projects’ compliance and functional success. Project information was obtained from scientific and government databases and gray literature. Despite considerable investment in offsetting projects, crucial problems persisted. Although compliance and function were related to each other, a high level of compliance did not guarantee a high degree of function. However, large projects relative to area had better function than small projects. Function improved when projects targeted productivity or specific ecosystem features and when multiple complementary management targets were in place. Restorative measures were more likely to achieve targets than creating entirely new ecosystems. Altogether the relationships we found highlight specific ecological processes that may help improve offsetting outcomes.