• Day-to-day variability in the carbon isotope composition of phloem sap (δ 13 C hd ) and ecosystem respiratory CO 2 (δ 13 C R ) were measured to assess the tightness of coupling between canopy photosynthesis (δ 13 C hd ) and ecosystem respiration (δ 13 C R ) in two mature Nothofagus solandri (Hook. f.) forests in New Zealand. • Abundant phloem-tapping scale insects allowed repeated, nondestructive access to stem phloem sap 1-2 m above ground.δ 13 C hd was compared with δ 13 C predicted by an environmentally driven, process-based canopy photosynthesis model. Keeling plots of within-canopy CO 2 were used to estimate δ 13 C R . • By including a lag of 3 d, there was good agreement in the timing and direction of variation in δ 13 C hd and predictions by the canopy photosynthesis model, suggesting that δ 13 C hd represents a photosynthesis-weighted, integrative record of canopy photosynthesis and conductance. • Significant day-to-day variability in δ 13 C R was recorded at one of the two forests. At this site, δ 13 C R reflected variability in δ 13 C hd only on days with <2 mm rain. We conclude that the degree of coupling between canopy photosynthesis and ecosystem respiration varies between sites, and with environmental conditions at a single site.

https://www.jstor.org/stable/pdfplus/1514693.pdf

Variation in the degree of coupling between δ13C of phloem sap and ecosystem respiration in two mature Nothofagus forests

Rod P. MACFARLANE, PEtER A. MAddISoN, IAN G. ANdREW, JoCELyN A. BERRy, PEtER M. JoHNS, RoBERt J. B. HoARE, MARIE-CLAudE LARIvIÈRE, PENELoPE GREENSLAdE, RoSA C. HENdERSoN, CouRtENAy N. SMItHERS, RICARdo L. PALMA, JoHN B. WARd, RoBERt L. C. PILGRIM, dAvId R. toWNS, IAN McLELLAN, dAvId A. J. tEuLoN, tERRy R. HItCHINGS, vICtoR F. EAStoP, NICHoLAS A. MARtIN, MuRRAy J. FLEtCHER, MARLoN A. W. StuFKENS, PAMELA J. dALE, dANIEL BuRCKHARdt, tHoMAS R. BuCKLEy, StEvEN A. tREWICK

Phylum Arthropoda, subphylum hexapoda: Protura, springtails, Diplura, and insects

Summary • Day-to-day variability in the carbon isotope composition of phloem sap ( δ 13 C hd ) and ecosystem respiratory CO 2 ( δ 13 C R ) were measured to assess the tightness of coupling between canopy photosynthesis ( δ 13 C hd ) and ecosystem respiration ( δ 13 C R ) in two mature Nothofagus solandri (Hook. f.) forests in New Zealand. • Abundant phloem-tapping scale insects allowed repeated, nondestructive access to stem phloem sap 1‐2 m above ground. δ 13 C hd was compared with δ 13 C predicted by an environmentally driven, process-based canopy photosynthesis model. Keeling plots of within-canopy CO 2 were used to estimate δ 13 C R . • By including a lag of 3 d, there was good agreement in the timing and direction of variation in δ 13 C hd and predictions by the canopy photosynthesis model, suggesting that δ 13 C hd represents a photosynthesis-weighted, integrative record of canopy photosynthesis and conductance. • Significant day-to-day variability in δ 13 C R was recorded at one of the two forests. At this site, δ 13 C R reflected variability in δ 13 C hd only on days with <2 mm rain. We

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phloem sap and ecosystem respiration in two mature Nothofagus forests

The invertebrates directly associated with the southern hemisphere tree genus Nothofagus are described and discussed in terms of their organization into guilds and attributes of their hostplants Using literature records, comparisons are made of the guild composition between host species and provenances; a full invertebrate-hostplant list is appended Sap-sucking Homoptera are particularly diverse and usually host-species specific whereas defoliating insects seem less prevalent and less specific Few seed-eating insects are reported Some provenances and hostplants exhibit local radiations in certain taxa, such as Eriococcidae in New Zealand, Notophorina psyllids in South America and scolytid beetles on N dombeyi Environmental stresses such as drought, disturbance and landslips, can induce outbreaks of certain scale insects and borers, affecting the dynamics of the forest Generally, however, the influence of invertebrates appears benign, but occasional large-scale defoliation is observed on N solandri var cliffortioides, N moorei, N antarctica and N pumilio Collectively this fauna has two elements: a geographically recurrent Gondwanic element, usually monophagous, and a provenance-specific element (often polyphagous) locally recruited following vicariance of the host genus The fauna of Nothofagus can be in stark contrast to that of adjacent forest types In Australia, the insect profile of Nothofagus has more in common with fagaceous trees on other continents than the more recent Eucalyptus forests which surround it There is almost no evidence of fauna transfer from Nothofagus to Eucalyptus Relative to New Zealand, the Australian Nothofagus fauna is depauperate and may reflect truncation in Pleistocene glaciations Typically low insect populations on these trees may partly explain the limited range of insectivorous birds and spiders observed in Australia Much more data on the phytophagous insects of this biome is needed for comparative purposes The fauna of the montane tropical subgenus Brassospora pollen group is almost unknown but could hold the key to the origin of fagaceous insect communities more generally The conservation value of remaining Nothofagus forests is enhanced by recognition of their co-adapted fauna, some of which are arranged in stable functional groups likely to give valuable insight into invertebrate-hostplant interactions originating in the Cretaceous Elucidation of its role in the processes of these unique forests remains a fertile field for endeavour in the future

Nothofagus (Fagaceae) and its invertebrate fauna—an overview and preliminary synthesis

Keystone Species: Competition for Honeydew Among Exotic and Indigenous Species

The endemic New Zealand coccoid genera Coelostomidia , Platycoelostoma , and Ultracoelostoma are revised. Four new species are described, and six species are redescribed, with designation of lectotypes as necessary. The immature female life stages of all ten species and the male stages of five are described and illustrated. The adult females and first instars of two introduced species of Icerya are described. Keys are given to all life stages of the endemic genera. The life histories of Coelostomidia wairoensis (Maskell) and Ultracoelostoma brittini n. sp. are described and illustrated. Brief summaries are given of the classification of the Margarodidae, their economic importance, biology, life history, host-plant associations, and collection and mounting techniques. Work done on this group in New Zealand is reviewed Checklist of taxa Subfamily COELOSTOMIDIINAE Tribe Coelostomidiini Genus Coelostomidia Cockerell deboerae new species jenniferae new species montana (Green) pilosa (Maskell) wairoensis (Maskell) zealandica (Maskell) Genus Ultracoelostoma Cockerell assimile (Maskell) brittini new species dracophylli new species Tribe Platycoelostomini Genus Platycoelostoma Morrison and Morrison compressa (Maskell) Subfamily MONOPHLEBINAE Tribe Iceryini Genus Icerya Signoret purchasi Maskell

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Clare F Morales

Papers

Margarodidae (Insecta: Hemiptera).