A model-based assessment of the environmental impact of land-use change across scales in Southern Amazonia

Regional Environmental Change - This article describes the design of a new model-based assessment framework to identify and analyse possible future trajectories of agricultural development and...     

How to overcome the development deadlock in the Quilombo Vila Formosa,Brazil?

ABSTRACT

Although Brazilian Quilombolas possess specific land rights referring to their past as African slaves, the realization of such rights often fails due to the absence of land surveys, clarified institutional competencies and the general lack of power under which minorities suffer. Additional factors such as an expanding commercial agriculture contributing to land and water degradation and new actors introducing new logics intransparent to traditional populations often aggravate the situation. In order to identify options for traditional populations to overcome a development-deadlock typical for peripheral regions, the case of a Quilombo in Pará/Brazil will be analysed that has been struggling since decades with conflicting land tenure legislations and institutions. Starting from an inter- and transdisciplinary qualitative research process, scenario building by backcasting can represent an innovative approach to organize the central conflicts which have to be solved in order to overcome the development deadlock of the Quilombo Vila Formosa in Pará.     

Where to find a mate? Resource-based sexual communication of webbing clothes moth

Mate location in moths typically entails long-range attraction of males to female-produced pheromone. Here, we show that male and female webbing clothes moths, Tineola bisselliella, seek larval habitats (dry carrion, animal lairs, etc) to encounter mates. With males seeking, and arriving at, larval habitat earlier at night than females, male-produced pheromonal and sonic signals enhance the habitat's attractiveness to females. This resource-based mating strategy of T. bisselliella differs from that known for most other moths. It may have evolved in response to larval habitats that are patchy and temporary, but that disseminate attractive semiochemicals so abundantly that T. bisselliella encounter them more readily than their own pheromones.     

(<Emphasis Type="Italic">Z,Z</Emphasis>)-11,13-Hexadecadienyl acetate and (<Emphasis Type="Italic">Z,E</Emphasis>)-11,13,15-hexadecatrienyl acetate: synergistic sex pheromone components of oak processionary moth,Thaumetopoea processionea (Lepidoptera: Thaumetopoeidae)

Summary. Our objective was to identify sex pheromone components of the oak processionary moth, Thaumetopoea processionea (Lepidoptera: Thaumetopoeidae), whose larvae defoliate oak, Quercus spp., forests in Eurasia and impact human health. Coupled gas chromatographic-electroantennographic detection (GC-EAD) and GC-mass spectrometric (MS) analyses of pheromone gland extract of female T. processionea revealed two consistently EAD-active compounds. They were identified as (Z,Z)-11,13-hexadecadienyl acetate (Z11,Z13-16:OAc) and (Z,E)-11,13,15-hexadecatrienyl acetate (Z11,E13,15-16:OAc) by comparative GC, GC-MS and GC-EAD analyses of insect-produced compounds and authentic standards. In replicated field experiments (2000, 2001) in Nordbaden, Südbaden and Sachsen-Anhalt (Germany), Z11,Z13-16:OAc and Z11,E13,15-16:OAc in combination, but not singly, attracted significant numbers of male moths. It will now be intriguing to investigate whether Z11,E13,15-16:OAc, or its corresponding alcohol or aldehyde, serves as a pheromone component also in other species of the Thaumetopoeidae.     

Historical and current atmospheric deposition to the epilithic lichen Xanthoparmelia in Maricopa County,Arizona

Spatial patterns of atmospheric deposition of trace elements to an epilithic lichen were assessed using a spatial grid of 28 field sites in 1998 throughout Maricopa County, Arizona, USA. In addition, samples of Xanthoparmelia spp. from Arizona State University lichen herbarium material (1975-1976) was utilized for a limited number of sites in order to explore temporal trends. The lichen material was cleaned, wet digested and analyzed by ICP-MS for a suite of elemental concentrations [antimony (Sb), cadmium (Cd), cerium (Ce), chromium (Cr), cobalt (Co), copper (Cu), dysprosium (Dy), europium (Eu), gadolinium (Gd), gold (Au), holmium (Ho), lead (Pb), lutetium (Lu), neodymium (Nd), nickel (Ni), palladium (Pd), platinum (Pt), praseodymium (Pr), samarium (Sm), scandium (Sc), silver (Ag), terbium (Tb), thulium (Tm), tin (Sn), uranium (U), ytterbium (Yb), yttrium (Y), and zinc (Zn)]. Cluster analysis and principal component analysis suggest three major factors, which, depending on regional aerosol fractionation, explain most of the variation in elemental signatures: (1) a group of widely distributed rare earth elements (2) a highly homogenous Co, Cr, Ni, and Sc component representing the influence of mafic rocks, and (3) anthropogenic emissions. Elemental concentrations in Maricopa County lichens were generally comparable to those reported for relatively unpolluted areas. Only highly urbanized regions, such as the greater Phoenix Metropolitan Area and the NW corner of the county, exhibited elevated concentrations for Zn, Cu, Pb, and Cd. Lead levels in lichens have fallen over the last 30 years by 71%, while Zn concentrations for some regions have increased by as much as 245%. From the spatial pattern of elemental deposition for Cd, Cu, Ni, Pr, Pb, and Cu, we infer that agriculture, mining, industrial activities, and traffic probably are the major air pollutant sources in Maricopa County.     

The toxicity of soil samples containing TNT and other ammunition derived compounds in the enchytraeid and collembola-biotest

The effect of ammunition-like compounds and armament waste on the mortality and reproduction of terrestrial invertebrates was assayed by using two biotests: the enchytraeid-biotest withEnchytraeus crypticus and the collembola-biotest withFolsomia Candida. Toxicity was investigated by using standard soil (Lufa 2.2) spiked with 2,4,6-trinitrotoluene (TNT), hexahydro-l,3,5-trinitro-l,3,5-triazine (hexogen, RDX), octahydro-l,3,5,7-tetranitro-l,3,5,7-tetrazocine (octogen, HMX) and 2,4,6-triaminotoluene (TAT). Ecotoxicity was investigated with ammunition-contaminated soil material from the former ammunition plant “Tanne” at Clausthal-Zellerfeld (CTNTla) and the Brandplatz (incineration site) in Torgau-Elsnig (TETNT1a), Germany. TNT increased mortality and reduced reproduction of both test organisms corresponding to the concentrations used, whereas hexogen, octogen and TAT had no effect in the tested concentrations (1000-2000 mg/kg). From the two soil materials, TETNT1a was much more toxic than CTNT1a. The LC50(7d) in the enchytraeid-biotest was 570 mg TNT/kg and the EC50(28d) 369 mg TNT/kg soil material (dw). In the collembola-biotest the LC50(7d) was 185 mg TNT/kg and the EC50(28d) 110 mg TNT/kg soil matter (dw).     

Hierarchical Bayesian scaling of soil properties across urban, agricultural, and desert ecosystems.

Ecologists increasingly use plot-scale data to inform research and policy related to regional and global environmental change. For soil chemistry research, scaling from the plot to the region is especially difficult due to high spatial variability at all scales. We used a hierarchical Bayesian model of plot-scale soil nutrient pools to predict storage of soil organic carbon (oC), inorganic carbon (iC), total nitrogen (N), and available phosphorus (avP) in a 7962-km2 area including the Phoenix, Arizona, USA, metropolitan area and its desert and agricultural surroundings. The Bayesian approach was compared to a traditional approach that multiplied mean values for urban mesic residential, urban xeric residential, nonresidential urban, agricultural, and desert areas by the aerial coverage of each land-use type. Both approaches suggest that oC, N, and avP are correlated with each other and are higher (in g/m2) in mesic residential and agricultural areas than in deserts or xeric residential areas. In addition to traditional biophysical variables, cultural variables related to impervious surface cover, tree cover, and turfgrass cover were significant in regression models predicting the regional distribution of soil properties. We estimate that 1140 Gg of oC have accumulated in human-dominated soils of this region, but a significant portion of this new C has a very short mean residence time in mesic yards and agricultural soils. For N, we estimate that 130 Gg have accumulated in soils, which explains a significant portion of "missing N" observed in the regional N budget. Predictions for iC differed between the approaches because the Bayesian approach predicted iC as a function of elevation while the traditional approach employed only land use. We suggest that Bayesian scaling enables models that are flexible enough to accommodate the diverse factors controlling soil chemistry in desert, urban, and agricultural ecosystems and, thus, may represent an important tool for ecological scaling that spans land-use types. Urban planners and city managers attempting to reduce C emissions and N pollution should consider ways that landscape choices and impervious surface cover affect city-wide soil C, N, and P storage.     

Carbon-optimised land management strategies for southern Amazonia

Regional Environmental Change -     

Volatiles from the bark of trembling aspen, Populus tremuloides Michx. (Salicaceae) disrupt secondary attraction by the mountain pine beetle, Dendroctonus ponderosae Hopkins (Coleoptera: Scolytidae)

Summary. Coupled gas chromatographic-electroantennographic detection (GC-EAD) analysis of the Porapak Q-captured volatiles from the bark of trembling aspen, Populus tremuloides Michx., revealed four compounds that consistently elicited antennal responses by mountain pine beetles (MPBs), Dendroctonus ponderosae Hopkins. One of these, 1-hexanol, disrupted the capture of MPBs in multiple-funnel traps baited with the aggregation pheromones trans-verbenol and exo-brevicomin and the host kairomone myrcene, a blend of semiochemicals that mediates the secondary attraction response in which beetles mass attack and kill living pines. The other three EAD-active aspen bark volatiles, benzyl alcohol, benzaldehyde and nonanal, were inactive alone, but in binary and ternary combinations contributed to a disruptive effect in an additive and redundant manner when all four aspen bark volatiles were tested in all possible binary and ternary blends. The best ternary blend and the quarternary blend achieved ≥ 80% disruption. The quarternary blend enhanced the disruptive effect of the antiaggregation pheromone verbenone in traps, raising the disruptive effect to 98%, and also enhanced the inhibition of attack on attractant-baited lodgepole pines. This is the first demonstration of specific compounds from the bark of angiosperm trees that disrupt the secondary attraction response of sympatric coniferophagous bark beetles. The results support the hypothesis that such bark beetles are adapted to recognize and avoid non-host angiosperm trees by responding to a broad spectrum of volatiles that can act in various blends with equal effect. Received 27 October 1997; accepted 20 February 1998.