A Fifty-Year Perspective on the Indian Reorganization Act

The achievement of John Collier, commissioner of Indian Affairs under Franklin Delano Roosevelt and father of the Indian Reorganization Act (IRA), has been increasingly ignored or denigrated by the anthropological profession, upon whose advice Collier relied to reverse the nation's Indian policy and resuscitate the inherent powers of Indian tribes. I assert that but for the IRA, Indian tribal governments would probably not exist today. I also attempt to refute those critics who assert (1) that the U.S. government imposed elective systems on the Indians against their will; (2) that even though Indian voters may have voted to accept the IRA, the vast majority indicated their rejection of the act by not voting at all; (3) that IRA governments are "puppet" governments; and (4) that Indians have lost independence and freedom as a result of the IRA. The tribal structures created or revived by the IRA are now vigorous and growing in power and authority, and I postulate that with the growth among anthropologists of a "resistance model" of Indian. White relations and the gradual repudiation of the assimilationist model held by most anthropologists 50 years ago, Collier's policy of locating tribal autonomy within the federal system of government rather than in resistance to it came to be seen as a "cop-out" by anthropologists who failed to realize that without the policy Indian tribal governments would probably soon have ceased to exist.     

景观生态学:两栖动物生态学研究的新途径

全球两栖动物正以远超过自然灭绝的高速率灭绝,这与生境丧失和景观破碎化有着直接关系。生境丧失导致两栖动物的生存空间减少,使局部种群消失,而景观破碎化则导致两栖动物种群之间的隔离度增加,不利于动物的繁殖和扩散。但两者往往是同时出现,相互作用。复合种群、景观连接度、景观遗传学及景观模型模拟等理论和方法的发展,为在生境丧失与破碎化景观下两栖动物的种群结构、组成和动态变化研究提供了理论基础和技术方法。同时景观生态学中特别重视研究的尺度,生境破碎化是发生在景观尺度下的生境变化过程,因此对生境破碎化的影响应该从现有的主要集中在斑块尺度和斑块-景观尺度转变到景观尺度上来。     

Spatially Explicit Modeling in Ecology: A Review

The use of spatially explicit models (SEMs) in ecology has grown enormously in the past two decades. One major advancement has been that fine-scale details of landscapes, and of spatially dependent biological processes, such as dispersal and invasion, can now be simulated with great precision, due to improvements in computer technology. Many areas of modeling have shifted toward a focus on capturing these fine-scale details, to improve mechanistic understanding of ecosystems. However, spatially implicit models (SIMs) have played a dominant role in ecology, and arguments have been made that SIMs, which account for the effects of space without specifying spatial positions, have an advantage of being simpler and more broadly applicable, perhaps contributing more to understanding. We address this debate by comparing SEMs and SIMs in examples from the past few decades of modeling research. We argue that, although SIMs have been the dominant approach in the incorporation of space in theoretical ecology, SEMs have unique advantages for addressing pragmatic questions concerning species populations or communities in specific places, because local conditions, such as spatial heterogeneities, organism behaviors, and other contingencies, produce dynamics and patterns that usually cannot be incorporated into simpler SIMs. SEMs are also able to describe mechanisms at the local scale that can create amplifying positive feedbacks at that scale, creating emergent patterns at larger scales, and therefore are important to basic ecological theory. We review the use of SEMs at the level of populations, interacting populations, food webs, and ecosystems and argue that SEMs are not only essential in pragmatic issues, but must play a role in the understanding of causal relationships on landscapes.     

Products and Ecological Models: A Population Ecology Perspective

Industrial ecology has used the systems ecology model, with its emphasis on the flows of energy and nutrients, as a tool to find ways to minimize the adverse environmental effects of industrial activity. A second ecosystem model, the population ecology model, emphasizes intra-and inter-specific interactions of many types. When applied to industrial systems, it suggests an increased focus on products. It therefore can provide a useful complement to the systems ecology approach. If industrial processes that are less harmful to the environment are to be successfully implemented, they will have to produce products that can successfully penetrate the marketplace. A number of historical examples are used to illustrate the many product interactions discussed.     

扬子鳄(Alligator sinensis)生态学研究进展

简要介绍了半个多世纪以来,扬子鳄自然种群的变化、种群衰落的原因、生活史对策、栖息地选择、行为生态、生理生态等方面的主要研究成果,并对将来的研究进行了展望。     

干旱与半干旱地区苔藓植物生态学研究综述

苔藓植物一般生活在阴湿的地方,但也有不少种类具有极强的耐旱性,在干旱和半干旱地区也有分布,在干旱和半干旱地区,影响苔藓植物分布的环境因子包括降水,pH值,CaCO3含量,植被盖度,有机质含量以及土壤质地等,其中起沙,固沙和生态小环境的改善中发挥着不可替代的作用。     

复口吸虫的研究进展

复口吸虫是淡水鱼类的一种常见的寄生虫,在欧洲、亚洲和北美等地区均有复口吸虫的分布。复口吸虫的生活史是一个复杂过程,分别经过虫卵、毛蚴、胞蚴、尾蚴、后囊蚴和成虫阶段,其中间寄主分别为第一中间寄主螺、第二中间寄主鱼和终末寄主鸟。在自然水体里,特别是在人工养殖水体中,复口吸虫具有明显的致病性,能使第二中间寄主鱼产生一系列的病症,严重的能引起寄主鱼的大量死亡。科学家对其的研究比较深入和广泛,而本文仅对复口吸虫的分类学、生活史、流行病学和致病机理的研究进展进行介绍。     

Protozoan Ecology: A Note on Its Current Status

Most data in the broad field of protozoan ecology, even if onerestricts the subject to consideration of free-living species,are scattered through the literature and are generally of anunsophisticated nature. Review articles are few in number and/orout of date. In view of their high adaptability, their ubiquitousness,their numerousness, and their short generation time, it is perhapssurprising that protozoan forms have not been subjected to morestudy, both intensive and extensive in kind. The recognitionin recent years of the possible role(s) played by the Protozoain problems of pollution has caused renewed interest in manyof these microorganisms. The inherent difficulties of propertaxonomic identification of the species under study and of morerefined methods for carrying out desirable laboratory experimentationcan be overcome, but time, motivation, and technical innovativenessare required. Because protozoan species are the ideal organismsto be investigated in many environmental situations, the fieldof protozoan ecology should develop significantly in the yearsahead.     

Restoration Ecology and the Ecosystem Perspective

The ecosystem perspective provides a framework within which most other aspects of the ecology of restoration can be incorporated. By considering the ecosystem functions of a restoration project, the restorationist is forced to consider the placement of the project in the landscape—its boundaries, its connections or lack thereof to adjoining ecosystems, and its receipts and losses of materials and energy from its physical surroundings. These characteristics may set limits on the kind(s) of biotic communities that can be created on the site. The ecosystem perspective also gives restorationists conceptual tools for structuring and evaluating restorations. These include the mass balance approach to nutrient, pollutant, and energy budgets; subsidy/stress effects of inputs; food web architecture; feedback among ecosystem components; efficiency of nutrient transfers, primary productivity and decomposition as system-determining rates; and disturbance regimes. However, there are many uncertainties concerning these concepts, their relation to each other, and their relationships to population- and community-level phenomena. The nature of restoration projects provides a unique opportunity for research on these problems; the large spatial scale of restorations and the freedom to manipulate species, soil, water, and even the landscape could allow ecosystem-level experiments to be conducted that could not be performed otherwise.     

Breeding Ecology of Mottled Ducks: A Review

Mottled ducks (Anas fulvigula) are endemic to the Gulf Coast of North America, and their range stretches from Alabama to the Laguna Madre of Mexico, with a distinct population in peninsular Florida and an introduced population in South Carolina. As one of the few non-migratory ducks in North America, mottled ducks depend on a variety of locally available habitat throughout the annual cycle, and threats to these landscapes may affect mottled ducks more acutely than migratory species. Annual population monitoring has revealed declines in mottled duck populations in Texas and Louisiana since 2008, and the genetic integrity of the Florida population has been muddled by the presence of large numbers of feral mallards (Anas platyrhynchos) resulting in hybridization. Similar to other closely related dabbling ducks, mottled duck populations are influenced by recruitment and breeding season survival, so changes in these factors may contribute to population decline. Accordingly, researchers have attempted to address various aspects of mottled duck breeding season ecology and population dynamics since the 1950s. We conducted a literature review on this topic by searching a combination of key terms using Google Scholar, including mottled duck, nesting ecology, habitat use, breeding incidence, nest success, brood, and breeding season survival, and followed citation trees to eventually aggregate information from nearly 50 publications on mottled duck breeding ecology. Our review concluded that mottled ducks use brackish and intermediate coastal marsh, including managed impoundments, and agricultural land during the breeding season. Their nests can be found in pastures, levees, dry cordgrass marsh, cutgrass marsh, spoil banks, and small islands. Nesting propensity and nest success estimates are often lower than other waterfowl species that are characterized by stable or increasing populations. Broods use wetlands composed of a mix of open water with submerged and emergent vegetation. Breeding season survival is higher for the Florida population than the western Gulf Coast population, but adult survival in both geographies is comparable to (or higher than) that of other dabbling duck species. Breeding habitat use, breeding season survival, and nest-site selection and success have been studied extensively in mottled ducks, whereas information on nesting propensity, renesting intensity, and post-hatch ecology is lacking. © 2021 The Wildlife Society.     

根系分泌物生态学研究

在植物生长过程中 ,由根系的不同部位分泌或溢泌一些无机离子及有机化合物 ,这些物质统称为根系分泌物。植物在其生长过程中不断地分泌无机离子及有机化合物 ,这是植物长期适应外界环境而形成的一种适应机制。早在 2 0世纪 5 0年代就有人对植物根系分泌物进行了研究 ,Ｒｏｖｉｒａ等[4 3] 和Ｖａｎｃｕｒａ等[4 7] 对根土界面根系分泌物进行了系统的研究 ,切尔诺布里维卡[2 6 ] 研究了植物根系分泌物的生物学作用 ,揭示了其在间作中的作用 ,直到 70年代对根系分泌物的研究才出现了蓬勃发展的趋势。近年来的研究表明 ,根系分泌物是保持根际微…     

水生低等脊椎动物病毒生态学研究

初次系统介绍两栖类、爬行类和鱼类病毒学的专著<低等脊椎动物病毒学>于1989年问世[1],是目前尚处在萌芽期的水生低等脊椎动物病毒生态学的基础文献之一.可将生态学分为以个体和群体为中心同其环境关系的宏观生态学、以(单)细胞为中心同其环境关系的微生态学、及以细胞内的生物活性分子为中心同其分子环境关系的分子生态学[2]等3个层次.水生低等脊椎动物病毒生态学旨在阐明病毒与宿主及水环境之间的各种作用及其机理,探讨病毒与宿主在水体环境中相互作用而产生的生理平衡态与病理失调的机制,以因势利导,寻求维持宿主生理平衡、防止病理失调及保护水体环境的措施.     

Accounting for Imperfect Detection in Ecology: A Quantitative Review

Detection in studies of species abundance and distribution is often imperfect. Assuming perfect detection introduces bias into estimation that can weaken inference upon which understanding and policy are based. Despite availability of numerous methods designed to address this assumption, many refereed papers in ecology fail to account for non-detection error. We conducted a quantitative literature review of 537 ecological articles to measure the degree to which studies of different taxa, at various scales, and over time have accounted for imperfect detection. Overall, just 23% of articles accounted for imperfect detection. The probability that an article incorporated imperfect detection increased with time and varied among taxa studied; studies of vertebrates were more likely to incorporate imperfect detection. Among articles that reported detection probability, 70% contained per-survey estimates of detection that were less than 0.5. For articles in which constancy of detection was tested, 86% reported significant variation. We hope that our findings prompt more ecologists to consider carefully the detection process when designing studies and analyzing results, especially for sub-disciplines where incorporation of imperfect detection in study design and analysis so far has been lacking.     

A Review and Perspective on Cathodoluminescence Analysis of Halide Perovskites

Halide perovskite solar cells have achieved a certified efficiency of 25.2%, surpassing CdTe and CuInGaSe₂, which have long been regarded as the most‐efficient thin‐film photovoltaic materials. As this exciting class of materials continues to mature, researchers will require characterization techniques capable of exposing the interplay among structure, chemistry, and optoelectronic properties to inform processing strategies and increase both device efficiencies and long‐term stability. Cathodoluminescence microscopy is an ideal technique to provide such information due to the high spatial resolution and robust optical information acquired. Here, the current body of work related to cathodoluminescence analysis of halide perovskite materials for optoelectronic applications is surveyed. This review demonstrates how cathodoluminescence can monitor degradation due to environmental stressors, phase segregation resulting from material processing, and other halide perovskite‐centric material issues. A persistent concern associated with e‐beam‐based analysis of halide perovskites is what effect the electron beam has on the material properties being probed. Addressing this, a detailed discussion is provided on the origin of the cathodoluminescence signal and a review of studies focused on revealing changes in the properties of halide perovskites resulting from e‐beam excitation. Finally, a perspective on future opportunities to expand the role of cathodoluminescence analysis for halide perovskites is provided.     

种子生态学专辑评述

通过多次到中国学术访问, 得知许多中国学者围绕植物种子在基础研究和应用领域开展了多学科的研究。此次《植物生态学报》种子生态学专辑将向读者集中介绍中国学者在种子生态学这一有趣专题的研究进展。该专辑刊登了23篇论文, 包括19篇研究论文和4篇综述论文, 涉及种子传播、种子性状、种子休眠和萌发、土壤种子库以及幼苗生长对变化环境的响应等多方面的研究内容, 我们对这些论文进行了简单的评述。由于篇幅的限制, 该专辑所刊登出的论文只是当前中国学者对植物种子多方面研究的一小部分内容。该专辑的刊出将为国内外学者对种子研究的合作交流提供便利, 也将向参加中国2013年第四届国际种子生态学学术研讨会的国内外专家介绍中国学者在种子生态学等领域的研究现状。     

第七届热带森林生态学学术研讨会述评

为持续加强热带森林生态学科技工作者之间的相互了解、促进学术交流与合作。2016年8月12—14日在海口举行了以"做实生态学基础,服务美丽热区建设"为主题的第七届热带森林生态学学术研讨会,有18位生态学领域的研究者做了学术报告,报告内容涵盖了热带森林生态服务功能评估、热带森林生态系统物质与能量的循环、环境对热带森林物质能量循环的影响、海南岛植物区系与海南岛的起源、热带植物种类资源调查分析、热带生态资源资产核算、热带人工林生态及科学发展、以及热带森林生态学野外观测技术等。