An Anatomy of Adaptation to Climate Change and Variability

Adaptation to climate variability and change is important both for impact assessment (to estimate adaptations which are likely to occur) and for policy development (to advise on or prescribe adaptations). This paper proposes an "anatomy of adaptation" to systematically specify and differentiate adaptations, based upon three questions: (i) adapt to what? (ii) who or what adapts? and (iii) how does adaptation occur? Climatic stimuli include changes in long-term mean conditions and variability about means, both current and future, and including extremes. Adaptation depends fundamentally on the characteristics of the system of interest, including its sensitivities and vulnerabilities. The nature of adaptation processes and forms can be distinguished by numerous attributes including timing, purposefulness, and effect. The paper notes the contribution of conceptual and numerical models and empirical studies to the understanding of adaptation, and outlines approaches to the normative evaluation of adaptation measures and strategies.     

A re-examination of petrogenesis and 40Ar/39Ar systematics in the Chain of Ponds K-feldspar: “diffusion domain” archetype versus polyphase hygrochronology

K-feldspar (Kfs) from the Chain of Ponds Pluton (CPP) is the archetypal reference material, upon which thermochronological modeling of Ar diffusion in discrete “domains” was founded. We re-examine the CPP Kfs using cathodoluminescence and back-scattered electron imaging, transmission electron microscopy, and electron probe microanalysis. ⁴⁰Ar/³⁹Ar stepwise heating experiments on different sieve fractions, and on handpicked and unpicked aliquots, are compared. Our results reproduce the staircase-shaped age spectrum and the Arrhenius trajectory of the literature sample, confirming that samples collected from the same locality have an identical Ar isotope record. Even the most pristine-looking Kfs from the CPP contains successive generations of secondary, metasomatic/retrograde mineral replacements that post-date magmatic crystallization. These chemically and chronologically distinct phases are responsible for its staircase-shaped age spectra, which are modified by handpicking. While genuine within-grain diffusion gradients are not ruled out by these data, this study demonstrates that the most important control on staircase-shaped age spectra is the simultaneous presence of heterochemical, diachronous post-magmatic mineral growth. At least five distinct mineral species were identified in the Kfs separate, three of which can be traced to external fluids interacting with the CPP in a chemically open system. Sieve fractions have size-shifted Arrhenius trajectories, negating the existence of the smallest “diffusion domains.” Heterochemical phases also play an important role in producing nonlinear trajectories. In vacuo degassing rates recovered from Arrhenius plots are neither related to true Fick’s Law diffusion nor to the staircase shape of the age spectra. The CPP Kfs used to define the “diffusion domain” model demonstrates the predominance of metasomatic alteration by hydrothermal fluids and recrystallization in establishing the natural Ar distribution among different coexisting phases that gives rise to the staircase-shaped age spectrum. Microbeam imaging of textures is as essential for ⁴⁰Ar/³⁹Ar hygrochronology as it is for U–Pb geochronology.     

Digital preprocessing techniques for GLORIA II sonar images

Image processing techniques are discussed that correct distortions in GLORIA II side scan sonar imagery including water column offset, slant-range distortion, multiple returns, aspect ratio, speckle noise, striping, and cross-track power drop-off. The software operates within NASA's ELAS image processing system and is applied to the original 12-bit GLORIA II data. Procedures are discussed for generating large scale mosaics and three-dimensional overlays with sea floor bathymetry. The results are shown in four sonographs acquired off the southern coast of California.     

Private rights,public benefits: Industry-driven seabed protection

New Zealand has a large exclusive economic zone (EEZ) that contains a variety of marine habitats and commercially-important species. The commercial fishing industry operating within New Zealand's EEZ is of significant value to the economy and fisheries resources are managed through the extensive use of Individual Transferable Quotas (ITQs). One of the benefits of ITQs has been to better align some of the private incentives of quota owners with the public interest. These incentives contributed to an initiative proposed by the fishing industry to close large areas of New Zealand's EEZ to protect the seabed from trawling. These closed areas are termed benthic protection areas (BPAs) and protect the benthic biodiversity of about 1.1 million square kilometres of seabed—approximately 30% of New Zealand's EEZ. A significant proportion of New Zealand's known seamounts and active hydrothermal vents are protected by these closed areas. We describe and discuss the criteria used to select BPAs and some of the criticism of this marine protection initiative. We argue that the assignment of strong property rights in fishing resources was an important precondition to an industry initiative that has a significant public benefit. Where private and public interests are well aligned, government can adopt an enabling and facilitation role, ceding direct control of processes in order to get the results the align with the public interest.     

Environmental impacts of shrimp farming with special reference to the situation in the continental United States

Shrimp culture technology has resulted in development of a major shrimp farming industry worldwide. Without the shrimp farming industry, increasing demands for shrimp by consumers could not be met, resulting in increased pressure on wild shrimp resources. Unfortunately, there are realized and potential adverse environmental effects on estuarine ecosystems as a result of shrimp farming. The effects can be categorized as wetland destruction for construction of shrimp farms, hypernutrification of estuarine ecosystems by shrim pond effluent, “biological pollution” of native shrimp stocks through escapement of aquaculture stocks, water use and entrainment of estuarine biota, and impacts of shrimp farm chemicals on estuarine systems. While the shrimp farming industry in the United States is small, the United States is effectively addressing all the realized and potential environmental impacts through regulation and research at the federal and state levels. Areas of regulation and research include stringent prohibitions on wetland destruction, regulation of effluents and support of research to eliminate and/or reduce effluents, escapement prevention technology and development of high-health stocks, minimizing entrainment of estuarine biota through water conservation and screening technology, and regulation of chemical use in the shrimp farming industry and support of research on shrimp pathology and environmentally safe disease control. Work is still in progress and not all problems have been resolved to the complete satisfaction of shrimp farmers and estuarine conservationists. However, the situation in the United States should serve as a model of how to encourage sustainable economic development through commercial shrimp farming while abating adverse environmental impacts on estuarine systems. To further improve the situation, the development and adoption of “best management practices” for shrimp aquaculture are recommended.     

Products and Mechanism of the Gas Phase Reaction of Ozone with β-Pinene

Gas phase ozonolysis of -pinene was performedin a 570 l static reactor at 730 Torr and 296 K insynthetic air and the products were analysed by acombination of gas phase FTIR spectroscopy, HPLC andIC analyses of gas phase and aerosol samples,respectively. The reaction mechanism was investigatedby adding HCHO, HCOOH and H₂O as Criegeeintermediate scavenger and cyclohexane as OH radicalscavenger. Main identified products (yields inparentheses) in the presence of cyclohexane as OHradical scavenger were HCHO (0.65 ± 0.04),nopinone (0.16 ± 0.04), 3-hydroxy-nopinone (0.15± 0.05), CO₂ (0.20 ± 0.04), CO (0.030± 0.002), HCOOH (0.020 ± 0.002), the secondaryozonide of -pinene (0.16 ± 0.05), andcis-pinic acid (0.02 ± 0.01). The decompositionof the primary ozonide was found to yieldpredominantly the excited C₉-Criegee intermediateand HCHO (0.84 ± 0.04) and to a minor extent theexcited CH₂OO intermediate and nopinone (0.16± 0.04). Roughly 40% of the excitedC₉-Criegee intermediate becomes stabilised andcould be shown to react with HCHO, HCOOH and H₂O. The atmospherically important reaction of thestabilised C₉-Criegee intermediate with H₂Owas found to result in a nopinone increase of (0.35± 0.05) and in the formation of H₂O₂(0.24 ± 0.03). Based on the observed products,the unimolecular decomposition/isomerisationchannels of the C₉-Criegee intermediate arediscussed in terms of the hydroperoxide and esterchannels. Subsequent reactions of the nopinonylradical, formed in the hydroperoxide channel, lead tomajor products like 3-hydroxy-nopinone but also tominor products like cis-pinic acid. A mechanismfor the formation of this dicarboxylic acid isproposed and its possible role in aerosol formationprocesses discussed.     

Middle Campanian–lowermost Maastrichtian nannofossil and foraminiferal biostratigraphy of the northwestern Australian margin

The middle–late Campanian was marked by an increase in the bioprovinciality of calcareous microfossil assemblages into distinct Tethyan, Transitional, and Austral Provinces that persisted to the end of the Maastrichtian. The northwestern Australian margin belonged to the Transitional Province and the absence of key Tethyan marker species such as Radotruncana calcarata and Gansserina gansseri has led petroleum companies operating in the area to use the locally developed KCCM integrated calcareous microfossil zonation scheme. The KCCM zonation is a composite scheme comprising calcareous nannofossil (KCN), planktonic foraminiferal (KPF) and benthonic foraminiferal (KBF) zones. This paper presents the definitions and revisions of Zones KCCM8–19, from the highest occurrence (HO) of Aspidolithus parcus constrictus to the lowest occurrence (LO) of Ceratolithoides aculeus, and builds on our previous early–late Maastrichtian study. The presence of a middle–upper Campanian disconformity is confirmed by microfossil evidence from the Vulcan Sub-basin, Exmouth and Wombat plateaus, and the Southern Carnarvon Platform. In the Vulcan Sub-basin and on the Exmouth Plateau (ODP Hole 762C) the hiatus extends from slightly above the LO of common Rugoglobigerina rugosa to above the LO of Quadrum gothicum. On the Wombat Plateau (ODP Hole 761B) it spans from above the LO of Heterohelix semicostata to above the LO of Quadrum gothicum; and in the Southern Carnarvon Platform the disconformity has its longest duration from above the HO of Heterohelix semicostata to above the LO of Quadrum sissinghii. A significant revision of the events which define Zones KCCM18 and 19 was necessary owing to the observation that the LO of Ceratolithoides aculeus occurs below the HOs of Archaeoglobigerina cretacea and Stensioeina granulata incondita and the LO of common Rugoglobigerina rugosa. In the original zonation these events were considered to be coincident.     

中国中部南洛河流域地貌、黄土堆积与更新世古人类生存环境

本文结合最近获得的新资料,对南洛河流域的地貌、黄土沉积和更新世环境进行综合分析。结果表明,南洛河上、中游地貌表现为河流峡谷和山间盆地相间分布的特征,盆地中河流阶地发育; 下游为平缓的山前平原和低山丘陵。黄土在全流域的山顶、河流阶地和盆地等各种地貌部位均有分布。黄土沉积受地形影响较大,上游黄土堆积速率低、颗粒细; 在下游有风道直通的地方,黄土堆积速率高、颗粒粗。在不同地貌部位,黄土开始堆积的年代不同,黄土底界的年代从早更新世到晚更新世均有所见。对埋藏旧石器的年代研究表明,南洛河流域的古人类活动从早更新世晚期(约800ka)开始,到晚更新世后期(约30ka)结束,期间有多期遗存。初步的孢粉和有机碳同位素分析表明,这里曾是森林草原景观,冰期时,乔木植被以松属为主,C4类型草本减少; 而间冰期时,乔木植被以松属-榆科占主导地位,C4类植物增多。古人类在黄土堆积期和古土壤发育期都可能在这个地方活动,但这一认识需要更多的证据支持。丰富的石制品分布和较为连续的黄土沉积,使南洛河流域成为理解更新世人类行为与环境的重要区域。     

Acute toxicity of bromochlorinated seawater to selected estuarine species with a comparison to chlorinated seawater toxicity

The acute toxicity of bromochlorinated estuarine water (ca. 20%) was determined for several estuarine organisms. The most sensitive species were oysters (Crassostrea virginica, larvae and juveniles) and copepods (Acartia tonsa) with 48-h LC₅₀'s of 0·10 to 0·21 mg BrCl/litre. Palaemonetes pugio was most tolerant with a 96-h LC₅₀ of 0·70 mg BrCl/litre. The fish species tested (Menidia menidia, Brevoortia tyrannus and Leiostomus xanthurus) all had a 96-h LC₅₀ of 0·21–0·23 mg BrCl/litre.The BrCl toxicity data are compared with Cl₂ toxicity data for the same species. When the LC₅₀'s are expressed as equivalents per litre, BrCl is found to be two to four times less toxic than Cl₂. The ranking of species in terms of sensitivity is the same for both disinfectants.Some data are provided concerning the decay rates of BrCl and Cl₂ in estuarine water. BrCl was found to decay more rapidly than Cl₂ at higher ammonia levels (0·25 mg NH₄-N/litre). The question of chemical speciation is discussed with particular reference to the differential toxicities.