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Evelyn Fox Keller’s work has long focused on the discontinuities that seem to punctuate discourses on living systems. The discourse of gene action, for example, focuses on the uncanny shift of agen...

Compaction-induced soil degradation is of growing importance as field machinery continues to increase in power and mass. Approaches to managing the impacts of soil compaction include minimisation (reduce load), remediation (tillage) and confinement (control traffic). Integrated ‘swarms’ of low-mass autonomous machinery have recently been suggested as a means of reducing compaction and an alternative to controlled traffic. In this study, combine and potato harvester machinery relationships were used to predict the specifications of potential low-mass harvesters for use in soil compaction modelling. Results suggested that combine harvester gross vehicle mass (GVM) must be less than 6 Mg to keep the modelled soil bulk density below 1.4 Mg m-3. With this constraint, 6-9 small harvesters (~50 kW) would be required to replace one Class 9 (>300 kW) harvester. A fleet of this size would require access to unloading facilities every 2.5-3 min for the modelled yield conditions. For root and tuber harvesting, which results in a high degree of soil disturbance, no low-mass harvester option was found that would avoid compacting the soil to unacceptable limits. Avoiding soil compaction while maintaining acceptable productivity will pose considerable design and logistics challenges for low-mass grain, root and tuber vegetable harvest machinery. The integration of controlled traffic farming (CTF) and medium-capacity autonomous machines (~10-20 Mg GVM for combine harvesters) may be a better solution for both soil compaction and operational logistics than low-mass swarm technology.

The activities of innovation system actors, particularly the importance of networks, entrepreneurs, and the role of intermediaries have not yet been integrated into a framework that explains innovation system performance at the project level. This study contributes by exploring the role of the innovation system’s actors with respect to its performance. Innovation system performance is studied using multiple cases of projects using statistical inference, network analysis, and fuzzy-set qualitative comparative analysis. The number of actors effectively involved in projects is positively associated with innovation system performance. The network of relationships in the case study innovation system was relatively open, such that the contribution of some actors only became available to the system through the conduit of other actors. Both researchers and intermediaries are highly involved and effective, and the intermediaries’ effectiveness contributes to innovation system performance. However, the perceived involvement or effectiveness of these and other actors did not, alone, ensure that the conditions required for innovation system performance were met. The research method and results apply to any innovation project, particularly those in highly regulated, technological fields. The present study’s findings demonstrate the application of innovation system theory at the project level. The study has important implications for integrating entrepreneurial marketing into innovation system policy and practice.

Salinity stress tolerance is a complex polygenic trait composed of numerous sub-traits that operate at very different timescales. This work elucidates the time-dependence and physiological mechanisms conferring differential salinity stress tolerance between Atriplex lntiformis (halophyte) and Medicago arborea (glycophyte) exposed to prolonged NaCl treatments grown in various soil types. Plant (leaf sap Na+, K+ and Cl− concentrations and osmolality, chlorophyll content, stomatal conductance) and soil characteristic (pH, soil and leachate electrical conductivity) were measured at monthly intervals for up to five months of salinity treatments and then correlated with each other. The overall poor performance of salt-grown M. arborea (compared with A. lentiformis) was associated with several factors. This included: (i) its strong reliance on organic osmolytes (hence, associated carbon costs) for osmotic adjustment; (ii) poor K+ retention that compromised stomatal opening; (iii) its inability to prevent Na+ loading into the xylem; and (iv) its poor shoot tissue tolerance, most likely due to inability to provide efficient Na+ sequestration in vacuoles. Also, the salinity of sandy loam soil was only ~50% of the salinity of irrigation water suggesting the possibility of long-term usage of saline irrigation in soils with low clay content.

The concept of irrigating crops with saline irrigation water is not new, but impacts of this practice on soil properties remain debatable, particularly the use of highly saline water. In this work, key soil chemical properties were assessed to a depth of 300 cm following 2.5 years of application of highly saline irrigation to a sodic texture-contrast soil (Brown Sodosol) in south-eastern Tasmania, Australia. Control plots (rainfall only) were compared to irrigation treatments of low (0.8 dS/m) and high salinity (16 dS/m) waters at application rates of both 200 and 800 mm/year. Whilst significant increases in both electrical conductivity and chloride concentration occurred throughout the soil profile in the high salinity treatment, these values were well below those of the irrigation water, indicating effective deep leaching. In the upper soil profile, 0–50 cm, of the high salinity treatments both the exchangeable Na+ and its ratio to total base cations (ESP) were significantly increased whilst the lower soil profile between 50 and 200 cm, was improved via both reduced alkalinity and sodicity. Leaching of the exchangeable base cations Ca2+, Mg2+ and K+ was significant in the upper soil profile (0–50 cm). As expected, the low salinity treatment (0.8 dS/m) had minimal impacts on soil chemical properties. The upper topsoil (0–10 cm) total organic carbon was significantly reduced in the high salinity plots and was negatively correlated with Cl− concentration. The data confirms the general concerns about application of saline irrigation, namely increased whole profile salinisation and upper soil profile (0–50 cm) sodicity, but they also show unexpected and desirable reductions in the lower soil profile (> 50 cm) alkalinity and sodicity. It appears the Na+ ions present in the saline waters led to differential leaching of base cations from the rooting zone, especially Ca2+ which then ameliorate the alkalinity and sodicity deeper in the soil profile (> 50 cm). Thus, surface application of gypsum may help sustain the application of highly saline waters; alternatively, subsurface irrigation above the sodic clayey subsoils could be trailed.

Innovation systems provide a structured approach to understanding innovation performance and failure. Two innovation system theories, structural and functional, provide the basis for understanding the failures of projects within the single innovation system under investigation. Many indicators of the strength of conditions in the model are important to innovation system performance. Fuzzy set qualitative comparative analysis is suitable for the validation of formative measurement models. The survey instrument meets validity criteria to the extent of this research and is a useful diagnostic tool for innovation system performance.

Innovation systems provide an approach to understanding, and managing, the innovation process. The application of structural theory from the sectoral innovations systems literature and the functional theory from technological systems literature to a series of projects provides an opportunity to explore how weaknesses in the innovation system relate to innovation failure. Findings from fuzzy set qualitative comparative analysis of multiple cases indicate that the weaknesses of the innovation system are recurrent across cases, and therefore, amenable to policy or management intervention to improve innovation outcomes. The weaknesses in structural theory conditions are more consistent than the weaknesses in technological theory conditions.

Background: Young saplings of Hopea odorata, a native dipterocarp in Vietnam, require shading to prevent photoinhibition but they must avoid competition that stagnates their growth.Aims: To develop a silvicultural regime by examining how the biomass production of H. odorata changes along a light gradient in gaps within Acacia hybrid plantations.Methods: Hopea odorata saplings were planted in 22-m-diameter circular gaps within a 3-year-old Acacia hybrid plantation and in 5-m and 7.5-m-wide strip gaps within a 2.5-year-old Acacia hybrid plantation.Results: In the circular gap, biomass growth increased nearly tenfold from the gap perimeter (GP) to about 9 m from the perimeter, and then decreased. This was associated with a fivefold increase in the absorption of photosynthetically active radiation (APAR) and a nearly twofold increase in light-use efficiency (LUE). The increasing APAR was primarily related to increasing H. odorata crown sizes and a reduction in shading from the Acacia hybrid. In the strip gaps...

Background: Mixtures of tropical acacia nurse crops and understorey native species have been established to aid forest restoration in Vietnam, but with partial success. Knowledge of physiological mechanisms underlying competitive interactions remains limited.Aims: To examine growth and physiological responses of Hopea odorata, a shade-tolerant dipterocarp, established within an Acacia hybrid (Acacia mangium × Acacia auriculiformis) nurse-crop plantation.Methods: H. odorata seedlings were planted within three 22-m diameter gaps in a 3-year-old Acacia hybrid plantation in Central Vietnam. Growth and physiology responses to an environmental gradient in gaps were examined over 2 years.Results: Growth rate and maximum rates of photosynthesis and stomatal conductance of H. odorata saplings increased significantly with increases in relative daily incident photosynthetically active radiation from 24% at the gap perimeter (GP) to 61% at the gap centre. Leaf N, P, and chlorophyll concentration were unaffected by po...

Large amounts of industrial wastewater, often of high in salt content, are produced by urban activities or industries which require reuse or disposal and thus can be potentially used in agriculture to ease the pressure on freshwater supply for irrigation. At the same time, plant performance in the field may be determined not only by salt concentration per se but also by confounding effects associated with soil physical and chemical properties. The purpose of this study was to investigate the effect of saline water irrigation (0–16 dS/m range) on the performance of two plant species, Atriplex lentiformis (xero halophyte) and Medicago arborea (glycophyte) grown in three soil texture setups – (1) clay, (2) sandy loam and (3) sandy loam over clay (texture-contrast) – under glasshouse conditions. Both plant species yielded higher biomass in the clay texture compared to other soil texture setups under all irrigation treatments. There was no significant variation in chlorophyll fluorescence with salt treatments but stomatal conductance was significantly reduced (up to 70%) by salinity in M. arborea. Overall, leaf ion content (Na+ and Cl _) also increased with increasing salinity treatment in both plants, but significant effects were seen only in sandy loam soil for both species. Both osmotic effect and specific ionic toxicity impacted physiological performance in M. arborea while A. lentiformis plants were insensitive to both components of salt stress. Plant performance in the sandy soil was not as good as in clay, indicating that soil texture and structure may have a significant role in the salt stress process under saline irrigation.

Theories of laughter exemplify the radical difference between descriptive language (“labels”) and actuality (“what occurs, including labels”). This difference is figured by Henri Bergson in his classic treatment of laughter as the mismatch between the mechanical and the living, a differential locus modeled herein with the help of a banana peel.

Biochar is increasingly being used as a soil amendment to both increase soil carbon storage and improve soil chemical and biological properties. To better understand the shorter-term (10 months) impacts of biochar on selected soil parameters and biological process in three different textured soils, a wide range of loading rates was applied. Biochar derived from eucalypt green waste was mixed at 0, 2.5, 5, 10 % (wt/wt) with a reactive black clay loam (BCL), a non-reactive red loam (RL) and a brown sandy loam (BSL) and placed in pots exposed to the natural elements. After 10 months of incubation, analysis was performed to determine the impacts of the biochar rates on the different soil types. Also, microbial biomass was estimated by the total viable counts (TVC) and DNA extraction. Moreover, potential nitrification rate and community metabolic profiles were assayed to evaluate microbial function and biological process in biochar-amended soils. The results showed that biochar additions had a significant impact on NH4 and NO3, total C and N, pH, EC, and soil moisture content in both a soil type and loading-dependent manner. In the heavier and reactive BCL, no significant impact was observed on the available P and K levels, or the total exchangeable base cations (TEB) and CEC. However, in the other lighter soils, biochar addition had a significant effect on the exchangeable Al, Ca, Mg, and Na levels and CEC. There was a relatively limited effect on microbial biomass in amended soils; however, biochar additions and its interactions with different soils reduced the potential nitrification at the higher biochar rate in the two lighter soils. Community metabolic profile results showed that the effect of biochar on carbon substrate utilization was both soil type and loading dependent. The BCL and BSL showed reduced rates of substrate utilization as biochar loading levels increased while the opposite occurred for the RL. This research shows that biochar can improve soil carbon levels and raise pH but varies with soil type. High biochar loading rates may also influence nitrification and the function and activity of microbial community in lighter soils.

Systematic approaches to understanding innovation are common, but these approaches still need testing as theories. This study aims to fill that gap by constructing sectoral and technological innovation-system failure models as theories and by testing those models using a multiple case study and fuzzy set qualitative comparative analysis. Both theories predict innovation system performance. Qualitative comparative analysis proved useful in both constructing and testing theory.

The use of biochar and compost as soil amendments and their comparative effects on microbial activities and related processes were investigated in an apple orchard site at Mountain River in Tasmania, Australia. Biochar derived from Acacia green waste was applied at a rate of 47 ton ha−1 just before planting and has been in situ for 3.5 years. Compost produced by the Luebke system was also applied separately at 10 ton ha−1 as a top dressing one week after planting. Chemical analysis indicated that there was no significant impact on total ions by either biochar or compost additions. However, organic carbon was significantly increased (p = 0.009) by 23% for biochar and 55% for compost treatments. Soil pH decreased in both biochar and compost treatments. Microbial abundance was improved after the addition of biochar, but the effect of compost addition was greater. There were no significant differences across a panel of enzyme activities among treatments. There were slight increases in alkaline phosphatase while fluorescein diacetate activity and hydrolysis activity slightly decreased. The entire community of the soil was assessed using 16S rRNA and 18S rRNA genes amplicon pyrosequencing. Significant differences in bacterial and fungal but not archaeal or other eukaryota community components were observed. These results indicated that biochar and compost carbon amendments can subtly affect the community structure of the orchard soils despite active application of inorganic and organic fertilizers. The overall effects on fundamental activity is largely neutral, however, likely due to the enormous structural resilience and functional redundancy present.

The world's food production will need to increase by up to 70% by 2050 to match the predicted population growth. Achieving this goal will be challenging due to the decreased availability of arable land, resulting from urbanization and land degradation. Soil salinity is a major factor contributing to the latter process. While some improvement in crop yields in saline soils may be achieved as a consequence of single gene transfers, the real progress may be achieved only via a painfully slow “pyramiding” of essential physiological traits. Given the time constraints, a safer solution to meet the 2050 challenge may be to find alternative crop and forage species for farming in salt-affected conditions and to restore salt-affected areas. This review focuses on the suitability of halophytes to become important components of 21st century farming systems. We provide a comprehensive summary of the current use of halophytes for human food consumption, for forage and animal feeds, as oilseed and energy crops, and for desalination and phytoremediation purposes. We argue that the use of halophytes may be a viable commercial alternative to ease pressure on the requirement of good quality land and water for conventional cropping systems and the utilization of land degraded by salinity.

The effects of biochar soil amendment on perennial plant nutrition and growth are poorly understood. We investigated the effects of a green waste biochar on apple rootstock (Malus domestica var. M26) nutrition and growth in a series of pot trials. Apple rootstocks were grown for 5 months in both soil and sand media, with and without biochar, under a range of fertilization, pH, and soil biological regimes. Plant biomass and leaf nutrient concentration of apple rootstocks and substrate-induced respiration (SIR) of the soil were measured. Addition of biochar was associated with significant increases in leaf concentrations of calcium (Ca), boron (B), and sulfur (S) for apple rootstocks grown in sand. Increased uptake of S has not previously been reported and may be the result of the relatively high S content of the biochar used in this trial that resulted from the low temperature used to pyrolize the biomass. Plant dry mass significantly increased by between 75% and 220% where sand was amended with biochar for every fertilization treatment. Small, but statistically significant, increases in soil pH, from pHc (CaCl2 extraction) 4.7 to 4.9, were found after the addition of biochar but no significant effect on soil SIR was detected. Our results indicate that biochar has positive effects on apple rootstock nutrition and growth in a sand but not in a sandy loam soil.

Background Lower respiratory tract infections (LRTIs) are one of the most common infectious disease-related emergency department (ED) visits in the United States. The ID Society of America and the Agency for Healthcare Research and Quality support the use of procalcitonin (PCT) for antimicrobial stewardship (ASP) in LRTI. Though not widely available, awareness and access to PCT is rising. At our facility, PCT became available in February 2018. The aim of our study is to assess the impact of PCT at an urban community hospital and identify possible targets for ASP interventions. Methods Retrospective review of cases from February to August 2018. Cases from the ED were selected for review. Appropriateness of testing was assessed, defined as guideline-based use for cessation of antibiotics in uncomplicated LRTIs without critical illness or immunosuppression. Demographic variables and clinical characteristics, such as, diagnosis, antimicrobial use and PCT levels were obtained. Results PCT was ordered 268 times hospital-wide, of which 160 (60%) were in the ED. Ages ranged from 0–90, with an average of 47. Most cases were male (51%). Appropriate testing for LRTI occurred in 33 (29%) cases. Antimicrobials were used in 75% of cases with low (< 0.5) PCT levels (Figure 1). Length of stay (LOS) was higher in groups that received antimicrobials (Figure 2). Testing was not appropriate in 127 cases (71%), with upper respiratory (21%), soft-tissue (17%), genitourinary (15%) and abdominal (13%) infections as the most common reasons for testing. Other diagnosis included alcohol withdrawal, seizures and altered mental status. Cumulative cost of PCT testing was $24000, of which $19050 was not consistent with guidelines. Conclusion Clinicians routinely ordered PCT in the ED. Antimicrobials were used for LRTIs despite low PCT levels. This may have contributed to higher LOS and excess antimicrobial use. Unwarranted PCT testing had a cost of $19050. As PCT becomes widely available in hospitals across the United States, education and decision support by ASP to clinicians may be needed to enhance guideline-appropriate evidence-based use of PCT. Targeted ASP interventions in the ED may have cost savings by reducing excess testing, length of stay and improving antimicrobial use. Disclosures All authors: No reported disclosures.

Knowledge of the soil water characteristic (SWC) and saturated hydraulic conductivity (Ksat) are required for simulation of soil water movement in most Richards’ equation based soil-water models. This study compared van Genuchten (VG) parameter values and Ksat determined by desorption with two rapid approaches, evaporative flux from intact cores, and inverse solution of tension infiltration data. Estimated and measured Ksat varied up to four orders of magnitude depending on parameterisation approach and antecedent soil moisture content. The SWC differed markedly between the laboratory drying and in situ wetting approaches due to the effects of hysteresis, air entrapment, clay swelling and water repellence. The evaporative flux approach was subjected to errors associated with prior saturation of the soil core, lack of K(ψ) data near saturation, and extrapolation of values beyond the measurement range of the upper tensiometer. Inverse solution of cumulative infiltration data from tension infiltrometers was able to discern the effects of antecedent soil moisture on soil structure and water repellence, however the approach had difficulty in obtaining unique local minima when the residual soil water content (θr) was included in the objective function. Both the evaporative flux and inverse solution of tension infiltration data approaches were improved by independent determination of the θr. Researchers should be aware that initial moisture content and methodology may influence VG parameter values, and that laboratory analysis of intact cores may result in Ksat and VG values which do not represent the hydraulic behaviour of field soils.

Twenty-four sites in northern Tasmania on Ferrosols formed on Tertiary basalt were sampled in 1997, 2005, and 2010. The farming systems at the sites during this period were either (a) continuous pasture, (b) continuous cropping of vegetable, cereal, and other cash crops in rotation, or (c) a mix of pasture and cropping (intermittent cropping). Average organic carbon (OC) concentrations across all sites and both sample depths (0–150 mm and 150–300 mm) decreased from 4.0% in 1997 to 3.5% in 2005 and 3.3% in 2010 (P < 0.001). Average OC was greater at 0–150 mm (4.1%) than at 150–300 mm (3.1%) (P < 0.001). Average total soil nitrogen (N) in 2010 (0.42%) at 0–150 mm was not significantly different (P = 0.07) from the average in 1997 (0.38%). Soil pH in water (pHw) showed the opposite trend to OC, increasing with time from 6.0 in 1997 to 6.2 in 2010. This reflects the consistent use of calcite and dolomite in Tasmanian farming because the natural pHw of these soils is less than 5.5. Exchangeable calcium and mag...

Many Tasmanian deposits previously described as ‘periglacial’ have been described in more detail, re-interpreted and dated. We suggest that ‘periglacial’ has little meaning when applied locally and the term ‘relict cold-climate deposits’ is more appropriate. In this paper we examine the origin and age of relict cold-climate slope deposits, fan alluvium and aeolian sediments in Tasmania, and infer the conditions under which they accumulated. Fan alluvium dating from the penultimate Glacial (OIS 6) and capped by a prominent palaeosol deduced to date to the Last Interglacial (OIS 5e) is present at Woodstock, south of Hobart. Many fan deposits formed before 40 ka or in a period c. 30–23 ka; only a few deposits date to the Last Glacial Maximum in Tasmania, which is defined as spanning the period 23.5–17.5 ka. Slope deposits indicate widespread instability down to present-day sea level throughout the Last Glacial, probably as a result of freeze–thaw in a sparsely vegetated landscape. Layered fine gravel and coarse sand colluvial deposits resembling grezes litees, produced both by dry deposition and by the action of water, are locally common where jointed siltstone bedrock outcrops. These deposits occur from altitudes of 500 m to near sea level and also in caves and must have formed under sparse vegetation cover, probably by freeze–thaw in extremely dry conditions. They have been radiocarbon dated from 35 to 17.5 cal. ka. Relict dunes and sandsheets are widespread at the margin of the Bassian Plain that once provided a land bridge between Tasmania and the mainland. They are also found in western Tasmania and in areas of inland southern Tasmania that now support wet eucalypt forest and rainforest and receive mean annual rainfall > 1500 mm. In the south they have been dated > 87.5–19 ka and attest to a long period of semi-arid climate in an area extending well to the west and south of the present semiarid zone. We deduce that during most of the Last Glacial anticyclones dominated Tasmania's climate and rain-bearing depressions generally passed south of the land mass. However in the east prominent palaeosols in aeolian deposits, dated between 26.4 ka and 16 ka at different locations, and palaeosols with morphology indicating formation under humid conditions, indicate periods of wetter climate in eastern Tasmania during or close to the LGM, deduced to be the result of easterlies associated with near-coastal depressions in the western Tasman Sea. Such easterlies may also be responsible for short Last Glacial wet periods noted at mainland coastal sites. A plot of ages of all dated deposits reveals an increase of erosion and deposition between 35 and 20 ka, and greater prevalence of aeolian deposits in the 35–15 ka period than earlier in the Last Glacial. There are two possible explanations for this pattern: (1) that aeolian activity increased as the result of climatic effects (e.g. increased windiness); or (2) that shrubland biomass increased after the megafauna were hunted to extinction following human arrival c. 40 ka, causing increased fire frequency, and in the cold dry climate of the late Last Glacial such fires caused increased erosion and increased aeolian accumulation.

Numerous and diverse reports indicate the efficacy of shamanic plant adjuncts (e.g., iboga, ayahuasca, psilocybin) for the care and treatment of addiction, post-traumatic stress disorder, cancer, cluster headaches, and depression. This article reports on a first-person healing of lifelong asthma and atopic dermatitis in the shamanic context of the contemporary Peruvian Amazon and the sometimes digital ontology of online communities. The article suggests that emerging language, concepts, and data drawn from the sciences of plant signaling and behavior regarding “plant intelligence” provide a useful heuristic framework for comprehending and actualizing the healing potentials of visionary plant “entheogens” (Wasson 1971) as represented both through first-person experience and online reports. Together with the paradigms and practices of plant signaling, biosemiotics provides a robust and coherent map for contextualizing the often reported experience of plant communication with ayahuasca and other entheogenic plants. The archetype of the “plant teachers” (called Doctores in the upper Amazon) is explored as a means for organizing and interacting with this data within an epistemology of the “hallucination/perception continuum (Fischer 1975). “Ecodelic” is offered as a new linguistic interface alongside “entheogen” (Wasson 1971).

Antecedent soil moisture significantly influenced the hydraulic conductivity of the A1, A2e and B21 horizons in a series of strong texture-contrast soils. Tension infiltration at six supply potentials demonstrated that in the A1 horizon, hydraulic conductivity was significantly lower in the ‘wet’ treatment than in the ‘dry’ treatment. However in the A2e horizon, micropore and mesopore hydraulic conductivity was lower in the ‘dry’ treatment than the ‘wet’ treatment, which was attributed to the precipitation of soluble amorphous silica. In the B21 horizon, desiccation of vertic clays resulted in the formation of shrinkage cracks which significantly increased near-saturated hydraulic conductivity and prevented the development of subsurface lateral flow in the ‘dry’ treatment. In the ‘wet’ treatment, the difference between the hydraulic conductivity of the A1 and B21 horizons was reduced; however, lateral flow still occurred in the A1 horizon due to difficulty displacing existing soil water further down the soil profile. Results demonstrate the need to account for temporal variation in soil porosity and hydraulic conductivity in soilwater model conceptualisation and parameterisation.

Congressional earmark reform efforts began in 2006. This paper reviews the literature on earmarks and documents the rise and relative fall in earmark spending using four databases. It identifies and critiques earmark reforms, including congressional rules and initiatives taken by the appropriations committees and congressional party organizations. Rules and committee-initiated reforms were the most effective, producing significant improvements in transparency and expediting availability of information. The number of earmarks and their dollar value first dropped noticeably in 2007 after an earmark moratorium, then stabilized as reforms were implemented. It is premature to conclude that reforms will alter the policy content of earmarks or their distribution.

Summary The effect of soil moisture status on preferential flow in a texture-contrast soil was investigated by applying 25 mm Brilliant Blue dye tracer to soil profiles at high and low antecedent soil moisture. Differences in soil morphology and chemistry between soil profiles had little effect on the depth of dye infiltration and dye distribution down the profile. Antecedent soil moisture strongly influenced the type, depth and rate of dye tracer movement. In the wet treatment, the dye tracer infiltrated to depths between 0.24 and 0.40 m, at an average rate of 120 mm h −1 . Whilst in the dry treatment, the same volume of dye tracer infiltrated to between 0.85 and 1.19 m depth at an average rate of 1160 mm h −1 . In dry antecedent conditions, finger flow developed in the A1 horizon as a result of water repellency. In the wet treatment, the wetting front developed permutations but did not break into fingers. Despite similar particle size distributions, flow in the A2 e was slower than the A1 horizon, due to the absence of macropores. In the dry treatment, the dye tracer ponded on the upper surface of the B21 horizon, which then spilled down the sides of the large clay columns as rivulets, at rates of between 2000 and 3000 mm h −1 . The dye tracer accumulated at the base of the columns resulting in backfilling of the inter column shrinkage cracks, at an estimated rate of 750 mm h −1 . In the subsoil, water movement occurred via shrinkage cracks which resulted in flow by-passing 99% of the soil matrix in the B21 horizon and 94% of the soil matrix in the B22 horizon. Evidence of rapid and deep infiltration in ‘dry’ texture-contrast soils has implications for water and solute management. This knowledge could be used to: (i) improve irrigation and fertilizer efficiency (ii) explain variations in crop yield (iii) reduce salinity through improved leaching practices, (iv) reduce the risk of agrochemicals contaminating shallow groundwater.

Since 1986, presidents have been required to submit an annual National Security Strategy (NSS). Recent years have seen a proliferation of national strategies of other kinds, linked in part to the NSS. The National Security Council, led by the national security advisor and employing its committee system and the interagency process, develops the NSS. The integration of all the necessary elements within the NSS involves an opaque and irregular set of rolling negotiations among national security principals. The 2006 NSS is best viewed in comparison to the 2002 version, which was issued in the immediate aftermath of 9/11. It stipulates that the United States is at war with transnational terrorism fueled by a perversion of Islam and proposes stable democracy as the primary solution, supported by aggressive efforts to control the proliferation of weapons of mass destruction and the option of taking preemptive military action. Criteria for assessing national security strategies can be process oriented or results based.

Soil genesis has been examined using field description, particle-size distributions, chemical properties, mineralogy and elemental distributions of five soil profiles developed on dolerite on Mt. Nelson and Tolmans Hill near Hobart in Tasmania. The soils form a sequence ranging from a Black Vertosol (P8) to four texture contrast soils, namely, a Eutrophic Brown Chromosol (P5), two Mottled-Subnatric Grey Sodosols (MN8 and P4), and a Mottled-Mesonatric Grey Sodosol (P7). The soil stratigraphic and pedological relationships of these soils have been investigated to help understand their distribution and improve understanding of soil formation history. The knowledge of the soil stratigraphy and weathering features aided in the determination of the broader landscape history. The field observations show the local dolerite has been subjected to both deep weathering and severe erosional periods. Pockets of deeply weathered dolerite occur adjacent to thin A/C soils or hard outcropping rock. Deeper colluvial soil materials occur on lower slopes. The presence of protruding dolerite columns now buried by transported clayey slope-wash materials indicates partial landscape stripping followed by reburial. The presence of buried stone-lines separating the upper profile from the clayey subsoils supports the idea of a second major erosional–depositional cycle. A pronounced variation between the A and B horizons particle-size distribution, mineralogy and elemental distribution supports the conclusion that the modern soils are composed of several sedimentary layers which cap a variable thickness of in situ weathered dolerite (termed “mealy material”) above fresh dolerite. Bedrock jointing, veins and rock fabric extend upward from the bedrock into the mealy material, but are truncated abruptly at the contact with the clayey subsoil. Soil-forming processes have operated to modify soil colours and mottling, soil structure and cation chemistry. These findings have important implications for landscape history, slope processes and the improved understanding of the distribution of dolerite-derived soils in Tasmania.

What happened is this: Once upon a time there was a narrative of vitality. Ok, not a narrative, but an apprehension, a fear, a vision. It didn't have a beginning, middle, or end. It was. Its contours were no more determinable than those of consciousness. Indeed, our consciousness, as humans, was our sole alleged difference from it. From something called "life." We were more than life, but were also, tragically, confined to it. You know the story all too well. Some of its major authors were Cuvier, Lamarck, Darwin, Bichat. Even Shelley. Just because this sudden transformation happened on paper doesn't mean it was easy to endure. Enormous numbers of humans went on tran- quilizers just to deal with the effects. Others, elsewhere, knew nothing but rumors. Nonetheless, they became increasingly implicated in its effects, the effects of understanding and experiencing both "life" and "conscious- ness" as informatic events. Suddenly—and it is sudden, a real surprise— both our vitality and our thought were distributed, scattered across a network and nowhere in particular. Timothy Leary and Francis Crick were speaking the same language, the language of information where the organic and the machinic enfold each other helically and, sometimes, the capacity for rep- lication goes through the ceiling. This new language of information would

President Clinton's veto of the 1995 reconciliation bill, the largest and most ambitious such legislation ever passed by Congress, was the first time a reconciliation bill was ever rejected by a president. It was also the first reconciliation bill in two decades to include a tax reduction rather than a tax increase. The fate of this bill, and its scope and contents, suggest the need to assess the evolution of reconciliation within the congressional budget process. In the early 1980s, Congress altered budget reconciliation procedures, putting in place a powerful new capability for deficit reduction. Reconciliation became the primary means within the budget process of restraining entitlement spending and increasing taxes as part of congressional efforts to reduce the deficit. Gramm‐Rudman‐Hollings magnified certain problems Congress encountered in using reconciliation to control entitlements, producing increased pressure to cut discretionary spending. While the Budget Enforcement Act of 1990 included new authority to use reconciliation to restrain entitlements, congressional spending priorities combined with the Peace Dividend to maintain the relative sanctuary entitlement programs have enjoyed. The limits of reconciliation as a deficit reduction tool, both in terms of increasing revenues and curtailing entitlements, are detailed. The inherent procedural advantages accorded to entitlements are contrasted with the treatment of discretionary programs, explaining in part the widening gulf between these two categories of spending. Congress has attempted, without success, to find alternatives to reconciliation. The failure of the seven‐year, deficit‐eliminating reconciliation bill of 1995 may indicate that certain Limits on the use of reconciliation may have been reached.

John Gilmour. Reconcilable diferences? Congress, the Budget Process, and the Deficit. Allen Schick, The Capacity to Budget. Richard Fenno, The Emergence of a Senate Leader: Pete Domenici and the Reagan Budget. Dennis Ippolito, Uncertain Legacies: Federal Budget Policy from Roosevelt through Rragan. Stanly Collender, The Guide to the Federal Budget, Fiscal 1992.

The Budget Enforcement Act of 1990, included in the controversial and comprehensive budget legislation passed by Congress in October, makes a number of significant changes in federal budgeting. It shifts the focus of the budget process from deficit reduction to spending control, provides five-year spending totals and mini-sequesters for defense, international and domestic appropriations, and puts entitlements and revenue expenditures on a pay-as-you-go basis. The Gramm-Rudman-Hollings deficit targets have been raised substantially, Social Security surpluses taken out of the deficit calculation and allowance made for further adjustments for inflation, Operation Desert Shield, and other emergency spending, minimizing the prospect for general sequestration. OMB has been given important new estimating authority and the roles of the congressional committees involved in budgeting have been altered.

Acacia hybrid (A. mangiumA. auriculiformis) is the main species planted for short-rotation forestry in Vietnam. In this study, the effect of these plantations on some key properties of degraded gravelly soils in Central Vietnam was assessed. Soil samples were collected from second- or third-rotation plantations representative of five age classes (0.5-5 years old), and in adjacent abandoned lands as controls. Compared with abandoned land, stock of total soil carbon (C) was significantly higher at ages 0.5, 1.5, 2.5 and 5 years (18.4-19.5 v. 13.0Mgha -1 ), total nitrogen (N) at 0.5 and 1.5 years (1.5-1.7 v. 1.0Mgha -1 ), exchangeable calcium at 0.5, 1.5 and 2.5 years (215-294 v. 42Mgha -1 ), magnesium at 0.5, 1.5, 2.5 and 3.5 years (39-48 v. 19Mgha -1 ), and sodium at all ages (46-59 v.5Mgha -1 ). Electrical conductivity was significantly higher at all ages (58.5-69.4 v. 32.7 mScm -1 ). Differences in extractable phosphorus and exchangeable potassium were not significantly different between plantations and abandoned land. Bulk density was significantly lower in plantations than abandoned land at all ages (1.36-1.42 v. 1.55Mgha -1 ), pHCaCl2 at 0.5 and 5 years (3.78-3.84 v. 3.98), and pHH2O at 5 years (4.30 v. 4.52). Because the soils were gravelly, differences in concentration of total C and nutrients between abandoned land and plantations were not the same as those for stocks after correction for gravel content and bulk density. Within a rotation, most soil properties did not change significantly with plantation age, although they appeared to decrease during the first 3 years; total C then recovered to initial levels, but total N and exchangeable cations remained lower. Some soil properties were strongly related to gravel content and elevation, but not to growth rate. We conclude that consecutive plantings of short-rotation Acacia hybrid on degraded and abandoned land can lead to changes in some soil properties. Additional keywords: degraded land, gravelly soil, nitrogen fixation, nutrient stock, soil amelioration.

The effects of environmental parameters, land-use history, and management practices on soil organic carbon (SOC) concentrations, nitrogen, and bulk density were determined in agricultural soils of four soil types in Tasmania. The sites sampled were Dermosols, Vertosols, Ferrosols, and a group of texture-contrast soils (Chromosol and Sodosol) each with a 10-year management history ranging from permanent perennial pasture to continuous cropping. Rainfall, Soil Order, and land use were all strong explanatory variables for differences in SOC, soil carbon stock, total nitrogen, and bulk density. Cropping sites had 29–35% less SOC in surface soils (0–0.1 m) than pasture sites as well as greater bulk densities. Clay-rich soils contained the greatest carbon stocks to 0.3 m depth under pasture, with Ferrosols containing a mean of 158 Mg C ha–1, Vertosols 112 Mg C ha–1, and Dermosols 107 Mg C ha–1. Texture-contrast soils with sandier textured topsoils under pasture had a mean of 69 Mg C ha–1. The range of values in soil carbon stocks indicates considerable uncertainty in baseline values for use in soil carbon accounting. Farmers can influence SOC more by their choice of land use than their day-to-day soil management. Although the influence of management is not as great as other inherent site variables, farmers can still select practices for their ability to retain more SOC.