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Poverty eradication, environmental conservation, and the United Nations Sustainable Development Goals cannot be achieved without the input and participation of disadvantaged communities in developing mitigation strategies. Over the last few decades, the markets for natural resources as niche products have grown exponentially. Morocco's production and international sales of argan oil are set to exceed current figures within the decade. We interviewed presidents of cooperatives in several villages in the Souss Massa region of Morocco to assess the current status of the argan oil trade, in particular women's roles in production, their economic status, and whether they have access to benefit sharing (ABS). Our results reveal that control over the argan oil trade has shifted into intermediaries that supply larger corporations, and that the survival of cooperatives and women's access to vital income are increasingly threatened. We argue thatthe implementation of ABS is essential to preserve women's access to income and their traditional knowledge associated with oil extraction processes and to ensure the conservation of argan ecosystems as prescribed by the Nagoya Protocol. [ABSTRACT FROM AUTHOR]

Poverty as an object of study in India continues to be the domain of economists, statisticians and demographers. The National Sample Survey Organisation (NSS) serves as the main instrument of data collection to measure poverty relative to economic indicators. In this paper we draw on strengths-based research undertaken in an Indian village to foreground alternative ways of conceptualising and practising data collection when measuring poverty. Explored through an analytics of biopolitics, asset-mapping exercises with young people and women revealed new subjectivities that emerged via illustrative meaning-making and dialogue. This approach to poverty measurement facilitated methods and produced outcomes that were less calculated and predefined than the NSS, and encouraged participation, even questioning of the status quo, in the 'doing' of the methodology itself. A strengths orientation to poverty opens up radical possibilities, particularly in India where the state-sanctioned self--governing body, the Gram Sabhas, has a mandate to provide for the most marginalised groups. And while this governing body is not free from power imbalances, the potential it offers, when combined with strengths-based approaches (SBA) that value people for the expertise they already have, demands renewed attention in practitioner and policy debates in the country. [ABSTRACT FROM AUTHOR]

Roots are the interface between the plant and the soil and play a central role in multiple ecosystem processes. With intensification of agricultural practices, rhizosphere processes are being disrupted and are causing degradation of the physical, chemical and biotic properties of soil. However, cover crops, a group of plants that provide ecosystem services, can be utilised during fallow periods or used as an intercrop to restore soil health. The effectiveness of ecosystem services provided by cover crops varies widely as very little breeding has occurred in these species. Improvement of ecosystem service performance is rarely considered as a breeding trait due to the complexities and challenges of belowground evaluation. Advancements in root phenotyping and genetic tools are critical in accelerating ecosystem service improvement in cover crops. In this study, we provide an overview of the range of belowground ecosystem services provided by cover crop roots: (1) soil structural remediation, (2) capture of soil resources and (3) maintenance of the rhizosphere and building of organic matter content. Based on the ecosystem services described, we outline current and promising phenotyping technologies and breeding strategies in cover crops that can enhance agricultural sustainability through improvement of root traits. Summary: Ecosystem service performance is rarely considered as a breeding trait due to the complexities and challenges of belowground evaluation. Advancements in phenotyping technologies and breeding strategies in cover crops are critical to agricultural sustainability through improvement of root traits. [ABSTRACT FROM AUTHOR]

Highlights • Ecological intensification management (EI) was compared with average farmer practice (FP). • We evaluated resource productivity and its components at the crop sequence level. • Water and radiation productivities were higher in EI than in FP. • Resource use efficiencies increased more than resource capture in EI as compared with FP. • The EI management reduced partial factor productivity of applied N but improved the partial N balance. Abstract The challenge to increase agricultural production with a minimum environmental impact requires to reach the maximum efficiency in the capture and use of resources such as photosynthetically active radiation (PAR), water, and nitrogen (N). Such requisites are encompassed in the ecological intensification (EI) concept. The aims of this work were to evaluate at a crop sequence level: i) crops yields, ii) water and radiation productivity and its components, i.e. resource capture and resource use efficiency, and iii) partial factor productivity of applied N (PFPN), partial nutrient balance for N (PNB), N uptake and N utilization efficiency of a two-year, three-crop sequence (wheat [ Triticum aestivum L.]/soybean [ Glycine max (L.) Merr.] double crop – maize [ Zea mays L.]) carried-out under EI principles in comparison with the same crop sequence under current farmer practices (FP) in two contrasting locations of the Argentinean Pampas, i.e. Paraná (-31°50′; -60°31′) at the northern Pampas and Balcarce (-37°45′, -58°18′) at the southern Pampas. Experiments were carried-out during four consecutive years, covering two complete cycles of the crop sequence. For the accumulated grain production of the crop sequence, EI management outyielded FP from 13 to 42%, depending on environmental conditions. Maize yield accounted for most of the variation (41–64%) of the accumulated grain yield of crop sequence, whether in EI as in FP. Average grain yield differences between EI and FP treatments were 274 g m−2 for maize, 69 g m−2 for wheat and -2 g m−2 for soybean. Water and radiation productivities of the sequence were higher in EI than in FP (26% for water and 17% for radiation; P < 0.0001), mainly because of increases in resource use efficiencies. EI reduced partial factor productivity of applied N, but improved partial nutrient balance for N as compared with FP. These reductions in partial factor productivity of applied N were less than proportional than the increases in N rate. Moreover, in spite of the higher N rate in EI respect to FP, N utilization efficiency (N ut E), i.e. grain per unit N uptake, was higher across all situations in EI. Our results showed that the challenge to obtain high grain yields by increasing N rate in a medium-input system could be achieved even with an increase in N ut E. Grain yields improvements, and increases in radiation and water productivity were reached by applying a set of agronomic practices that included improved genetics, crop and fertilizer N management englobed under EI concept. [ABSTRACT FROM AUTHOR]

In this article, I analyze the role of professionals (as part of the middle classes) and their communities in fostering reforms within the fields of higher education and social protection, and working towards, and supporting, the development of civil society. The analysis is based on the series of studies that explored lawmaking and policy-making processes in the fields of law, employment, social protection, rural development, tax policies and civil society development. The analysis of the work of professional communities, and the course of changes in these fields, indicates that policy networks had a major impact on the public policymaking process. These networks bring together typical representatives of the middle class: professionals, government officials, professional associations, representatives of modern non-governmental organizations, etc. The interests, upon which these networks were based, can be classified into three groups: (1) control of conditions of reproduction of the profession, (2) control of public resources in a given system (which includes, but is not limited to, control of the funding channels) and (3) control of conditions of reproduction of a given system. All these interests have a clear redistributive character, are -in general - focused on the control of public resources and have created an alliance between the middle classes and the elite. Middle classes have participated in the process of making laws and public policies in a way that has deepened the political inequalities, and to phenomena which, by analogy with the process of state capture by the elite, can be recognized as the capture of resources by the middle classes. The analysis points to an important aspect of sluggish social reforms: the lack of enthusiasm among middle classes and professional elite in fostering deep social change which is due to their ideological and redistributive alliances and strategies of “resources capturing.”

Abstract: The differences in functional traits between invasive plant species (invaders hereafter) and natives are believed to be closely associated with whether the former are successful invasion. Meanwhile, variability in the type of heavy metal pollution can alter the growth and physiological performance of invaders. Thus, determination of the potential effects of different types of heavy metal pollution on functional traits of invaders is vital for illuminating the mechanisms supporting the success of invaders. This study aims to address the effects of the separated treatment of Cu, Cd, and the combined treatments of Cu and Cd on functional traits of invasive redroot pigweed (Amaranthus retroflexus L.; pigweed hereafter) and native red amaranth (A. tricolor L.; amaranth hereafter). Pigweed was significantly taller than amaranth under most treatments. The greater height of pigweed may award greater competitive ability for resource acquisition (particularly sunlight). Leaf shape index of pigweed was significantly larger than that of amaranth under all treatments. The larger leaf shape index of pigweed can enhance the efficiency of resource capture (especially sunlight capture) via adjustments to leaf shape and size. Hence, the higher height and leaf shape index of pigweed may facilitate its further invasion process. Heavy metal pollution (especially Cd) poses significant adverse effects on the growth and physiological performance of the two Amaranthus species. This may be because heavy metal pollution, especially Cd, can mediate toxicity on plant species. The combined treatments of Cu and Cd can confer an antagonistic effect on functional traits of the two Amaranthus species compared with the separated treatment of Cu or Cd. The main reason may be the fact that Cd and Cu influence each other’s uptake for plants.Graphical Abstract: [ABSTRACT FROM AUTHOR]

Plant-soil feedbacks (PSFs) describe the effect of a plant species on soil properties, which affect the performance of future generations. Here we test the hypothesis that drought alters PSFs by reducing plant-microbe associations and nutrient uptake. We chose two grassland forb species, previously shown to respond differently to soil conditioning and drought, to test our hypothesis. We conditioned unsterilised grassland soil with one generation of each species, and left a third soil unconditioned. We grew a second generation consisting of each combination of plant species, soil, and drought in a full factorial design, and measured soil microbial community and nutrient availability. Scabiosa columbaria displayed negative PSF (smaller plants) under non-droughted conditions, but neutral under drought, suggesting that drought disrupts plant-soil interactions and can advantage the plant. Photosynthetic efficiency of S. columbaria was reduced under drought, but recovered on rewetting regardless of soil conditioning, indicating that PSFs do not impede resilience of this species. Sanguisorba minor showed positive PSFs (larger plants), probably due to an increase in soil N in conspecific soil, but neutral PSF under drought. PSF neutralisation appeared to occur through drought-induced change in the soil microbial community for this species. When S. minor was planted in conspecific soil, photosynthetic efficiency declined to almost zero, with no recovery following rewetting. We attributed this to increased demand for water through higher demand for nutrients with positive PSF. Here we show that drought neutralises PSFs of two grassland forbs, which could have implications for plant communities under climate change. [ABSTRACT FROM AUTHOR]

Mixed-species growth models are needed as a synthesis of ecological knowledge and for guiding forest management. Individual-tree models have been commonly used, but the difficulties of reliably scaling from the individual to the stand level are often underestimated. Emergent properties and statistical issues limit their effectiveness. A more holistic modelling of aggregates at the whole stand level is a potentially attractive alternative. This work explores methodology for developing biologically consistent dynamic mixture models where the state is described by aggregate stand-level variables for species or age/size cohorts. The methods are demonstrated and tested with a two-cohort model for spruce–aspen mixtures named SAM. The models combine single-species submodels and submodels for resource partitioning among the cohorts. The partitioning allows for differences in competitive strength among species and size classes, and for complementarity effects. Height growth reduction in suppressed cohorts is also modelled. SAM fits well the available data, and exhibits behaviors consistent with current ecological knowledge. The general framework can be applied to any number of cohorts, and should be useful as a basis for modelling other mixed-species or uneven-aged stands. [ABSTRACT FROM AUTHOR]

Integrated crop-livestock systems (ICL) have played an important role in human civilisation and have dominated the broadacre agricultural production system in the wheat-sheep zone of Australia. Over the past couple of decades, an increase in grain prices and decline in wool prices have led to the expansion of cropping into the high rainfall zone (HRZ) in southern Australia. While there has been a great deal of research into integrated crop-livestock systems for the medium to low rainfall environments in the wheat-sheep zone, there is much less information and many challenges confronting farmers to effectively integrate crops into the grazing systems in the high rainfall zone due to climatic and environmental differences and the complexity of the systems in Australia. This paper reviews the benefits of integrated crop-livestock systems and the challenges in implementing and managing these systems based on current Australian and international knowledge. The concept, types and terminology of integrated crop-livestock systems are discussed to provide greater clarity. Plant species, particularly annual and perennial legumes, are reviewed to find species with potential for use in integrated crop-livestock systems. Major gaps and opportunities for further research and development are identified, and recommendations proposed for developing effective integrated crop-livestock systems for the HRZ. These include: 1) Targeted R&D on ICL systems in the HRZ of southern Australia assisted with information from and outside Australia; 2) Biophysical and bio-economic modelling using current knowledge from the HRZ and other environments to guide future research; 3) Studies on N fixation, transfer and losses to develop strategies to balance N cycling and reduce N losses; 4) Development of compatible species/cultivars for ICL systems in the HRZ; 5) Management of waterlogging through ICL in the HRZ; 6) Effective stubble management to minimise the negative impact on crops and pastures; 7) Integrated research on grain yield reduction in crop-pasture intercropping, a potentially major type of ICL systems in the HRZ; and 8) Effective control of weeds, pests and diseases in ICL systems for the HRZ. [ABSTRACT FROM AUTHOR]

To examine the difference in photosynthetic traits and resource capture and use efficiency between three exotic plants (Eupatorium adenophorum Spreng, Alternanthera philoxeroides L. and Bidens pilosa L.) and three native plants (Picris divaricata Vaniot., Setaria plicata( Lam.) T. Cooke and Verbena officinalis L.), three exotic plants significantly possessed higher apparent quantum yield as compared with the two natives (P<0.05), P. divaricata and S. plicata. The two exotics, E. adenophorum and A. philoxeroides, significantly showed lower dark respiration rate compared to the three natives (P<0.05). The higher light compensation point was recorded in the two natives, P.divaricata and S. plicata (P<0.05). The three exotics significantly displayed higher maximum photosynthetic rate than that of the three natives ( P<0.05). The two exotics, E. adenophorum and A. philoxeroides, significantly exhibited lower stomatal conductance as compared to the other plants. Higher instantaneous water use efficiency was observed in the two exotics (E. adenophorum and A. philoxeroides.) compared with the two natives (P. divaricata and S. plicata). In addition, three exotics significantly had higher light resource use efficiency than that of the three natives. These results suggested the competitive advantage of the exotics over the natives at least in part from the resource capture and use efficiency and the tolerance to resource stress. [ABSTRACT FROM AUTHOR]

Intercropping is a common practice in low productivity (low input–low output) small-scale farming systems. However, as the level of productivity increases due to technological improvements whether intercropping – compared to sole cropping – remains the most productive and resource efficient cropping system is not well understood. Here we hypothesize that inter-crops outperform sole crops at low levels of resource availability because of improved resource capture and resource use efficiency; and answered whether this advantage decreases with increasing levels of resource availability. The performance of three cropping systems i.e. maize intercropped with navy bean, sole maize and sole navy bean were evaluated at three levels of resource input i.e. a low water/nitrogen (low W/N), a medium water/nitrogen (medium W/N), and a high water/nitrogen (high W/N), in three independent experiments, conducted over two consecutive years. The performance of the cropping systems was evaluated in terms of land equivalent ratios (LER), total grain yield, protein and energy productions as well as resource (water, nitrogen, and solar radiation) capture and use efficiency. Our results indicate that maize productivity (grain yield, protein and energy productions) was not significantly affected by the intercrop at any level of resource availability. However, irrespective of the level of resource input, intercropping significantly reduced the productivity of navy bean. The advantage of the intercropping, in terms of LER, tended to decrease with increasing the level of water and nitrogen supply i.e. decreased from 28% to 6% for above ground biomass, from 40% to 7% for grain yield, from 41% to 0.3% for protein production and from 40% to 9.2% for energy production. Intercropping was therefore more efficient in terms of LER under low W/N than under high W/N conditions. The LER was directly related to improved capture of nitrogen and to higher water use efficiency. Here we conclude that in terms of LER, intercropping systems are more resource efficient and suitable for lower productivity environments. As more productive technologies are adopted by smallholder farmers, agricultural development projects and extension services need to consider under what conditions sole cropping become a more productive system. [ABSTRACT FROM AUTHOR]

Cochlear implants (CIs) are auditory prostheses which restore hearing via electrical stimulation of the auditory nerve. The successful adaptation of auditory cognition to the CI input depends to a substantial degree on individual factors. We pursued an electrophysiological approach toward an analysis of cortical responses that reflect perceptual processing stages and higher-level responses to CI input. Performance and event-related potentials on two cross-modal discrimination-following-distraction (DFD) tasks from CI users and normal-hearing (NH) individuals were compared. The visual-auditory distraction task combined visual distraction with following auditory discrimination performance. Here, we observed similar cortical responses to visual distractors (Novelty-N2) and slowed, less accurate auditory discrimination performance in CI users when compared to NH individuals. Conversely, the auditory-visual distraction task was used to combine auditory distraction with visual discrimination performance. In this task we found attenuated cortical responses to auditory distractors (Novelty-P3), slowed visual discrimination performance, and attenuated cortical P3-responses to visual targets in CI users compared to NH individuals. These results suggest that CI users process auditory distractors differently than NH individuals and that the presence of auditory CI input has an adverse effect on the processing of visual targets and the visual discrimination ability in implanted individuals. We propose that this attenuation of the visual modality occurs through the allocation of neural resources to the CI input. [ABSTRACT FROM AUTHOR]

Modern lettuce cultivars are bred for use under high levels of input of water and nutrients, and therefore less adapted to low-input or organic conditions in which nitrate availability varies over time and within the soil profile. To create robust cultivars it is necessary to assess which traits contribute to optimal resource capture and maximum resource use efficiency. We therefore revisited earlier published results on root growth, resource capture and resource use efficiency of lettuce exposed to localized drought and nitrate shortage in a pot experiment. Root growth in a soil profile with localized resource shortage depended on the resource that was in short supply. We conceptualized a model describing nitrogen uptake and use efficiency. We also investigated the genetic variation among 148 cultivars in resource capture over time and soil depth and in resource use efficiency in four (two locations × two planting dates) field experiments. Cultivars proved to be highly diverse in their ability to capture and use resources. This ability, however, was strongly affected by other sources of variance, stressing the need for an eco-physiological model capable of reducing the residual variance and improving the expression and evaluation of cultivar differences in relation to both resource capture and use efficiency in lettuce. We showed that genetic variation was best expressed under limiting conditions. To improve the conceptualized model further we identified issues requiring further analysis, e.g., the physiological reasons why certain cultivars are capable of quickly responding to changes in the environment to maintain optimal resource capture. [ABSTRACT FROM AUTHOR]

Background and aims: To improve vegetable crops adapted to low input and variable resource availability, better understanding is needed of root system functioning, including nitrogen and water capture. Methods: This study quantified shoot and root development and patterns of water and nitrate capture of two lettuce cultivars subjected to temporary drought at two development stages (Trial 1) or to continuous, localized drought and/or nitrate shortage (Trial 2). Results: In Trial 1, early drought slowed down shoot and root growth, whereas late drought enhanced root proliferation in the top 0.1 m. Nitrate capture during drought was sustained by increased nitrate inflow from deeper layers. Plants did not recover fully from drought after re-watering. In Trial 2, root proliferation was stimulated in the drier soil compartment partially compensating reduced water availability and nitrate mobility. Under nitrate shortage, root proliferation was enhanced in the compartment where nitrate was more abundant, irrespective of water availability. Conclusions: Changes observed in the root system are 'feed-forward' mechanisms to sustain resource capture in a limiting growing environment. The type of stress (drought or nitrate shortage) affects coping strategies; nitrate concentration in the soil solution, combined with the nutritional status of the plant will determine the stress response. [ABSTRACT FROM AUTHOR]

Summary: •Although dynamic, plant competition is usually estimated as biomass differences at a single, arbitrary time; resource capture is rarely measured. This restricted approach perpetuates uncertainty. To address this problem, we characterized the competitive dynamics of Dactylis glomerata and Plantago lanceolata as continuous trajectories of biomass production and nitrogen (N) capture.•Plants were grown together or in isolation. Biomass and N content were measured at 17 harvests up to 76 d after sowing. Data were fitted to logistic models to derive instantaneous growth and N capture rates.•Plantago lanceolata was initially more competitive in terms of cumulative growth and N capture, but D. glomerata was eventually superior. Neighbours reduced maximum biomass, but influenced both maximum N capture and its rate constant. Timings of maximal instantaneous growth and N capture rates were similar between species when they were isolated, but separated by 16 d when they were competing, corresponding to a temporal convergence in maximum growth and N capture rates in each species. Plants processed N and produced biomass differently when they competed.•Biomass and N capture trajectories demonstrated that competitive outcomes depend crucially on when and how 'competition' is measured. This potentially compromises the interpretation of conventional competition experiments. [ABSTRACT FROM AUTHOR]

Abstract: Crops respond to N deficiency through a reduction in resource capture and/or resource use efficiency. The objective of this paper is to examine whether differences in this response pattern are associated with either metabolic group (C3 vs. C4) or botanical classification (mono- vs. dicotyledons). Hereto, we analysed the effect of N deficiency on the relationships between N uptake, LAI, and biomass accumulation, for maize, sorghum, wheat, canola, tall fescue, and sunflower, grown in experiments in either France or Australia. Maize and tall fescue maintained LAI per unit biomass (measure of resource capture) at the expense of N uptake per unit LAI (measure of resource use efficiency). Wheat and canola had the opposite response, whereas sunflower and sorghum were intermediate. In general, C4 species reduced N uptake per unit LAI more than C3 species. Species differences in the effect of N deficiency on resource use efficiency were associated with differences in the SLN or in the N storage capacity of the stems. For wheat, canola, and tall fescue, SLN declined with increasing LAI under high N conditions, and the minimum crop SLN under N deficiency was only marginally lower than under high N conditions. For sorghum, sunflower, and maize, crop SLN under high N changed little with increasing LAI, but the minimum crop SLN under N deficiency was considerably lower than under high N. Sorghum and maize were the only species that substantially decreased stem N uptake per unit LAI under N deficiency. Overall, our data suggest that C3 species are better able to maintain resource use efficiency under N stress than C4 species, and a survey of literature suggests this may be because in C4 species, the critical SLN for radiation use efficiency is higher than the critical SLN for leaf expansion, whereas the opposite is the case for C3 species. We hypothesise that species differences in response to N deficiency could be associated with these differences in critical SLN, which in turn could be a consequence of the lower photosynthetic nitrogen use efficiency of C3 crops. [Copyright &y& Elsevier]

Abstract: We tested the hypotheses that invasive species had higher irradiance plasticity, capture ability and efficiency than noninvasive species using two invasive aliens –Ageratina adenophora and Chromolaena odorata, and one noninvasive alien –Gynura sp. The three aliens were grown at 4.5%, 12.5%, 36%, 50% and 100% irradiances for 64 days before harvesting. The plastic response of specific leaf area (SLA) contributed to improved light interception at low irradiance, carbon gain and water balance at high irradiance. It was a good predictor for intraspecific irradiance responses of leaf area ratio (LAR), leaf area:root mass ratio, maximum photosynthetic rate (P max) and net assimilation rate (NAR). Biomass allocation-related traits were species specific and their plasticity to irradiance was low. The high root mass fraction, leaf mass fraction and LAR distinguished the two invaders from Gynura. However, other resource capture-related traits, such as SLA, NAR and P max, were not always higher for the invaders than for Gynura. Furthermore, plasticity to irradiance was not different between the invasive and noninvasive aliens. With increasing irradiance, Gynura decreased biomass investment to roots and leaves but increased the investment to support structures adversely affecting both low and high irradiance acclimation. Ageratina might invade new habitat successfully through tolerating shading at low irradiance and outshading competitors by forming dense stands when irradiance is increased. The results suggested that both resource capture-related traits and irradiance acclimation conferred competitive advantage to the two invaders and some traits were common for invasive and noninvasive aliens but others were specific for invaders. [Copyright &y& Elsevier]

Root density distribution of plants is a major indicator of competition between plants and determines resource capture from the soil. This experiment was conducted in 2005 at Anyang, located in the Yellow River region, Henan Province, China. Three cotton ( Gossypium hirsutum L.) cultivars were chosen: hybrid Bt-cultivar CRI46, conventional Bt-cultivars CRI44 and CRI45. Six planting densities were designed, ranging from 1.5 to 12.0 plants/m2Root parameters such as surface area, diameter and length were analyzed by using the DT-SCAN image analysis method. The root length density (RLD), root average diameter and root area index (RAI), root surface area per unit land area, were studied. The results showed that RLD and RAI differed between genotypes; hybrid CRI46 had significantly higher ( P < 0.05) RLD and RAI values than conventional cultivars, especially under low planting densities, less than 3.0 plants/m2The root area index (RAI) of hybrid CRI46 was 61% higher than of CRI44 and CRI45 at the flowering stage. The RLD and RAI were also significantly different ( P= 0.000) between planting densities. The depth distribution of RAI showed that at increasing planting densities RAI was increasingly distributed in the soil layers below 50 cm. The RAI of hybrid CRI46 was for all planting densities, obviously higher than other cultivars during the flowering and boll stages. It was concluded that the hybrid had a strong advantage in root maintenance preventing premature senescence of roots. The root diameter of hybrid CRI46 had a genetically higher root diameter at planting densities lower than 6.0 plants/m2Good associations were found between yield and RAI in different stages. The optimum planting density ranged from 4.50 plants/m2 to 6.75 plants/m2 for conventional cultivars and around 4.0–5.0 plants/m2 for hybrids. (Managing editor: Ya-Qin Han) [ABSTRACT FROM AUTHOR]

Abstract: The functional structural tree growth model ALMIS uses the individual based modelling approach and is implemented in the object-oriented programming language SIMULA. All features (state variables) and functions (processes) are specified locally, on the level of the single plant organs. Increasing numbers of “copies” (objects) of these elementary units, Internodes, Leaves, Meristems, Roots, and Root tips, form the growing tree. Various procedures (e.g. Photosynthesis, Nutrient_uptake, Transport, Storage, Mobilisation, Respiration, Growth) are employed to describe carbon and nutrient uptake, and matter fluxes between the different plant organs. Combining plant physiology and architecture, ALMIS allows studying the effect of single ecophysiological and structural processes on whole tree growth and in the tree–environment system. Some of these effects, driven by microclimate, self-shading, variable nutrient availability, variable transport dynamics, and branching patterns are exemplified. From the interactions at the organ and sub-organ levels new features emerge at higher levels of plant organisation. These so-called emergent properties are, for example, lifetime spectrum of single organs, space filling (“architecture”) and self-thinning of the crown. The most prominent emergent properties are the different growth forms of trees resulting from simulations under various conditions. Their causal interrelations are discussed in detail. [Copyright &y& Elsevier]

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In the arid grazing lands of central Australia, a previous study found that the size and composition of seed banks were changed by heavy grazing. In this concurrent study we found that grazing decreased the number of ‘safe sites’ for seeds by reducing soil stability and damaging broad-scale resource traps. The loss of ‘safe sites’ was likely to have had a greater initial impact on seed bank size than the direct effect of grazing on seed-bearing plants. In this environment, changes to the soil preceded changes to the vegetation, so that soil-based rather than vegetation-based indicators may provide a better early warning of rangeland deterioration. [Copyright &y& Elsevier]

To investigate the cost of the dimorphic cyanogenic system in Trifolium repens L., genotypes of the cyanogenic (T) and acyanogenic (T) morphs were grown in mixtures over a range of ratios and in pure stands at two levels of total density (low in a first experiment, high in a second experiment). The principles of the competition analysis employed were those related to the inverse linear model response. The morphs were compared using two interaction indices, the substitution rate and the relative resource total (RRT). The relative fitness of the two morphs, i.e. biomass and number of flowers per plant, suggests that the T morph has a competitive advantage over the T morph. [ABSTRACT FROM AUTHOR]