Geography and Recovery under the U.S. Endangered Species Act

Abstract: The U.S. Endangered Species Act (ESA) defines an endangered species as one “at risk of extinction throughout all or a significant portion of its range.” The prevailing interpretation of this phrase, which focuses exclusively on the overall viability of listed species without regard to their geographic distribution, has led to development of listing and recovery criteria with fundamental conceptual, legal, and practical shortcomings. The ESA's concept of endangerment is broader than the biological concept of extinction risk in that the “esthetic, ecological, educational, historical, recreational, and scientific” values provided by species are not necessarily furthered by a species mere existence, but rather by a species presence across much of its former range. The concept of “significant portion of range” thus implies an additional geographic component to recovery that may enhance viability, but also offers independent benefits that Congress intended the act to achieve. Although the ESA differs from other major endangered‐species protection laws because it acknowledges the distinct contribution of geography to recovery, it resembles the “representation, resiliency, and redundancy” conservation‐planning framework commonly referenced in recovery plans. To address representation, listing and recovery standards should consider not only what proportion of its former range a species inhabits, but the types of habitats a species occupies and the ecological role it plays there. Recovery planning for formerly widely distributed species (e.g., the gray wolf [Canis lupus]) exemplifies how the geographic component implicit in the ESA's definition of endangerment should be considered in determining recovery goals through identification of ecologically significant types or niche variation within the extent of listed species, subspecies, or “distinct population segments.” By linking listing and recovery standards to niche and ecosystem concepts, the concept of ecologically significant type offers a scientific framework that promotes more coherent dialogue concerning the societal decisions surrounding recovery of endangered species.     

Effectiveness of Scat‐Detection Dogs in Determining Species Presence in a Tropical Savanna Landscape

Abstract: Most protected areas are too small to sustain populations of wide‐ranging mammals; thus, identification and conservation of high‐quality habitat for those animals outside parks is often a high priority, particularly for regions where extensive land conversion is occurring. This is the case in the vicinity of Emas National Park, a small protected area in the Brazilian Cerrado. Over the last 40 years the native vegetation surrounding the park has been converted to agriculture, but the region still supports virtually all of the animals native to the area. We determined the effectiveness of scat‐detection dogs in detecting presence of five species of mammals threatened with extinction by habitat loss: maned wolf (Chrysocyon brachyurus), puma (Puma concolor), jaguar (Panthera onca), giant anteater (Myrmecophaga tridactyla), and giant armadillo (Priodontes maximus). The probability of scat detection varied among the five species and among survey quadrats of different size, but was consistent across team, season, and year. The probability of occurrence, determined from the presence of scat, in a randomly selected site within the study area ranged from 0.14 for jaguars, which occur primarily in the forested areas of the park, to 0.91 for maned wolves, the most widely distributed species in our study area. Most occurrences of giant armadillos in the park were in open grasslands, but in the agricultural matrix they tended to occur in riparian woodlands. At least one target species occurred in every survey quadrat, and giant armadillos, jaguars, and maned wolves were more likely to be present in quadrats located inside than outside the park. The effort required for detection of scats was highest for the two felids. We were able to detect the presence for each of five wide‐ranging species inside and outside the park and to assign occurrence probabilities to specific survey sites. Thus, scat dogs provide an effective survey tool for rare species even when accurate detection likelihoods are required. We believe the way we used scat‐detection dogs to determine the presence of species can be applied to the detection of other mammalian species in other ecosystems.     

Invasive Species Research to Meet the Needs of Resource Management and Planning

Abstract: As zebra mussels (Dreissena polymorpha) continue to spread among inland lakes of the United States and Canada, there is growing interest from professionals, citizens, and other stakeholders to know which lakes are likely to be colonized by zebra mussels. Thus, we developed a classification of lake suitability for zebra mussels on the basis of measured or estimated concentrations of dissolved calcium in lake water and applied the classification to >11,500 lakes in Wisconsin and the Upper Peninsula of Michigan. The majority of lakes (58%) were classified as unsuitable (<10 mg/L Ca) for survival and reproduction of zebra mussels, 27% were identified as suitable (≥21 mg/L Ca), and 15% were classified as borderline suitable (≥10 and <21 mg/L Ca). Of the 77 inland lakes with confirmed zebra mussel records for which data on dissolved calcium were available, our method classified 74 as suitable and 3 as borderline suitable. To communicate this lake‐specific suitability information and to help prioritize regional efforts to monitor and prevent the expansion of zebra mussels and other invasive species, we developed a web‐based interface (available from http://www.aissmartprevention.wisc.edu/ ). Although we are still uncertain of how access to suitability information ultimately affects decision making, we believe this is a useful case study of building communication channels among researchers, practitioners, and the public.     

昌黎生态监控区夏季浮游植物群落年际变化特征分析

为研究昌黎生态监控区夏季浮游植物群落结构特征及其与环境因子关系,采用2005~2013年夏季(8月)昌黎生态监控区海域浮游植物及环境因子的监测资料,基于Arc GIS 10.0和Canoco软件平台,运用典范对应分析方法,对浮游植物群落结构进行分析.结果表明,近9 a共鉴定出浮游植物3门23科39属105种,其中,硅藻门16科32属90种,占浮游植物总数的85.7%;甲藻门共6科6属14种,占总种类数的13.3%;金藻门1种.各年的优势种存在很大差异,按照优势度Y值的大小包括辐射圆筛藻(Coscinodiscus radiatus)、柔弱角毛藻(Coscinodiscus debilis)、笔尖根管藻(Rhizosolenia styliformis)、柏氏角管藻(Cerataulina bergoni)、威氏圆筛藻(Coscinodiscus wailesii)、海链藻(Thalassiosira sp.)、三角角藻(Ceratium tripos)、洛氏角毛藻(Coscinodiscus wailesii)、中肋骨条藻(Ceratium tripos)等.夏季细胞丰度年际变化较大,呈现逐渐降低的趋势.浮游植物的多样性指数H'值介于0.015~3.889,均匀度指数J值介于0.009~1,年际变化幅度较小;各站位间物种分布不均匀,优势种较少且优势度较大.对浮游植物群落与环境因子进行典范对应分析(CCA),结果表明影响夏季浮游植物群落结构变化的环境因子包括水温、营养盐(磷酸盐、硝酸氮、氨氮)、盐度等,且是各个环境因子相互作用的结果.     

水稻不同生育期根际与非根际土壤胞外酶对施氮的响应

与稻田土壤碳氮循环(矿化、转化等)密切相关的酶活性可以反映微生物的生长和代谢过程.为明确水稻不同生育期根际与非根际土壤胞外酶对施氮的响应,采用根际袋法区分水稻根际和非根际土壤,利用96微孔酶标板荧光分析法,测定其碳氮过程关键酶β-1,4-葡萄糖苷酶(BG)和β-1,4-N-乙酰氨基葡萄糖苷酶(NAG)活性,探讨根际效应、施氮和生育期对土壤酶活的影响及其调控机制.结果表明,施氮使拔节期土壤BG酶活性相对于不施氮处理降低了7.4~13.5 nmol·(g·h)~(-1),而使成熟期BG酶活性增大了7.0~31.4 nmol·(g·h)~(-1),同时根际与非根际土壤中BG酶活性也随水稻的生育期而发生相应的变化.与不施氮处理相比,施氮使水稻成熟期非根际土壤NAG酶活性增加了1.1倍,根际土壤降低了0.3倍.施氮和生育期显著影响土壤BG酶活性,而水稻生育期、施氮和根际效应及其交互作用均对NAG酶活性有极显著影响.RDA分析表明土壤微生物生物量碳(MBC)和可溶性有机碳(DOC)含量主要影响水稻根际土壤胞外酶活性;而非根际土壤中酶活性的变化主要受微生物生物量氮(MBN)和铵态氮(NH_4~+-N)的影响.土壤酶活性与多种因素存在复杂关系,需要综合考虑植物生理特征、土壤酶活性和土壤特征,分析N添加对微生物群落组成的影响.     

西安市重污染与清洁天PM2.5组分及其活性氧物质对比

针对重霾污染,在西安市冬季重污染日(2015-11-30~2015-12-09)和清洁日(2016-01-13~2016-01-22)各进行了为期10d的PM_(2.5)采集,测量其中的有机碳、元素碳,及NH_4~+、NO_3~-、SO_4~(2-)等无机水溶性离子,探讨两种污染条件下的组分特征及其成因.结果表明:观测期,重霾日和清洁日PM_(2.5)质量浓度分别为(170±47.5)μg·m~(-3)和(48.6±17.9)μg·m~(-3),且重霾日伴随低能见度、高湿静风等多种不利气象条件;重霾日二次无机离子(NH_4~+、NO_3~-、SO_4~(2-))组分占PM_(2.5)质量浓度的49.8%±13.1%,而清洁日为19.4%±5.95%,并且重霾日硫氧化速率(sulfur oxidation ratio,SOR)和氮氧化速率(nitrogen oxidation ratio,NOR)分别为0.282±0.157和0.269±0.124,远高于清洁日(SOR和NOR分别为0.189±0.057和0.077±0.046),重霾日二次有机组分浓度[(6.22±3.87)μg·m~(-3)]是清洁日[(1.44±1.63)μg·m~(-3)]的5倍,表明二次污染及不利气象条件是造成重霾期间相关组分浓度升高的重要原因.最后,通过二氯荧光黄双乙酸盐(2',7'-DCFH)化学荧光分析法测定了其中活性氧物质(reactive oxygen species,ROS)的浓度,探讨其对于二次无机组分形成的影响,结果表明观测期ROS平均浓度(以H_2O_2计)分别为(4.99±1.54)nmol·m~(-3)(重霾期),(0.492±0.356)nmol·m~(-3)(清洁期),二次反应及积累效应可能是西安重霾条件下ROS浓度升高的主要原因.NO_3~-、SO_4~(2-)与ROS均呈现正相关(P0.05),表明ROS可能通过二次氧化过程参与到二次无机组分形成过程中.     

Research on the degradation mechanism of pyridine in drinking water by dielectric barrier discharge

Pyridine, an important chemical raw material, is widely used in industry, for example in textiles,leather, printing, dyeing, etc. In this research, a dielectric barrier discharge(DBD) system was developed to remove pyridine, as a representative type of nitrogen heterocyclic compound in drinking water. First, the influence of the active species inhibitors tertiary butanol alcohol(TBA),HCO_3~-, and CO_3~(2-)on the degradation rate of pyridine was investigated to verify the existence of active species produced by the strong ionization discharge in the system. The intermediate and final products generated in the degradation process of pyridine were confirmed and analyzed through a series of analytical techniques, including liquid chromatography–mass spectrometry(LC–MS), high performance liquid chromatography(HPLC), ion chromatography(IC), total organic carbon(TOC) analysis, ultraviolet(UV) spectroscopy, etc. The results showed that the degradation of pyridine was mainly due to the strong oxidizing power of ozone and hydroxyl radical produced by the DBD system. Several intermediate products including 3-hydroxyl pyridine, fumaric acid, 2, 3-dihydroxypyridine, and oxalic acid were detected. Nitrogen was removed from the pyridine molecule to form nitrate. Through analysis of the degradation mechanism of pyridine, the oxidation pathway was deduced. The study provided a theoretical and experimental basis for the application of DBD strong ionization discharge in treatment of nitrogen heterocyclic compounds in drinking water.     

蚯蚓-微生物协同作用过程中的微生物特性

在环境污染治理领域,被誉为"生态型工程师"的蚯蚓在污水/污泥资源化处理与处置,以及土壤的生态修复中备受关注。蚯蚓通过掘洞、摄食、分泌黏液和排泄蚓粪等方式调控系统中微生物的数量、活性及群落结构,与微生物协同互作强化了生物系统中物质转化与能量流动关系。蚯蚓-微生物协同共生的相互依存关系是此类技术展现低耗高效和生态友好特点的关键。通过综述经人工强化的蚯蚓-微生物互作生态系统中,蚯蚓对微生物的量、活性、群落结构以及食物网的影响,探讨了该生态系统中物质转化和能量流动的特点,并展望了蚯蚓-微生物互作技术研究及应用的发展方向。     

不同粒径羟基磷灰石对污染土壤铜镉磷有效性和酶活性的影响

为研究不同粒径羟基磷灰石对重金属污染土壤的修复效果,采用向污染土壤添加常规磷灰石（150 μm）、微米（3 μm）和纳米（40 nm）羟基磷灰石的田间原位试验方法,考察其钝化修复5 a后对土壤铜镉磷有效性和酶活性的影响.结果表明:3种粒径羟基磷灰石均提高了土壤pH,降低了土壤交换性酸和交换性铝的含量,且微米羟基磷灰石处理效果最好.常规磷灰石、微米和纳米羟基磷灰石处理分别使w（离子交换态铜）降低了62.6%、74.3%和70.4%,w（离子交换态镉）降低了15.7%、25.3%和26.7%.3种材料均增加了土壤w（TP）,其中4.61%~17.4%和73.4%~89.8%分别转化为树脂磷和稳定态磷.微米羟基磷灰石处理分别使土壤脲酶活性和微生物量碳含量提高了4.66和0.66倍.研究显示,微米羟基磷灰石更有利于铜和镉由活性态向非活性态转化,增加土壤磷的有效性,提高土壤微生物活性,在我国南方重金属污染红壤区具有较好的应用潜力.      

废弃尾矿库15种植物对重金属Pb、Zn的积累和养分吸收

在废弃的铅锌尾矿库进行人工植被恢复试验.对3年生15种植物重金属积累和养分吸收特性的研究表明,植物对土壤重金属和养分的吸收积累因植物种类、部位、金属种类和种植时间的不同而有显著差异.树木不同器官Pb质量浓度高低的总趋势为根〉叶〉茎,部分树种Zn质量浓度表现为叶〉根和茎;在15种参试植物中,加拿大紫荆根系Pb和Zn质量浓度均处于最高水平（分别为1 803 mg.kg-1和2 120 mg.kg-1）,盐肤木具有最高的茎枝Pb、叶片Pb和Zn质量浓度（分别为280、546和1 507 mg.kg-1）,旱柳具有最高的茎枝Zn质量浓度（729 mg.kg-1）和较高的叶片Zn质量浓度（1 153 mg.kg-1）.枫香、紫花苜蓿对Pb,旱柳、盐肤木、紫花苜蓿对Zn的转移系数TF值均〉1.植物Pb的富集系数BCF值均小于0.17,旱柳、盐肤木、紫花苜蓿Zn的BCF值达0.37～0.43.固氮植物体内N含量显著高于其它植物,火炬树、臭椿对P和夹竹桃对K的吸收积累能力强.随着种植时间的增加,植株体内有重金属质量浓度增加、营养元素含量下降的趋势.盐肤木、旱柳等重金属积累树种及紫穗槐、紫花苜蓿、截叶胡枝子、桤木等固氮植物在铅锌尾矿治理中具有应用前景.