Enhancing farming system water productivity through alternative land use and improved water management of rainfed agriculture in Vertisol areas

Waterlogged Vertisols are amongst the high potential soils where management interventions could result in positive impacts. This study utilized soil, climate and crop and livestock productivity data and models to demonstrate intensification strategies which increase crop–livestock system productivity and to understand the effects of alternative land use and water management options on water productivity in the Vertisols areas. The areas have been classified into three slope classes including areas where artificial drainage is not feasible, where Broad Bed and Furrows (BBF) can be used to drain the excess water and naturally drained areas, represented by areas with 0–2%, 2–5% and over 5% slope steepness, respectively. Early planting of wheat (Triticum spp) using BBF on drainable areas and rice (Oryza sativa) or grasspea (Lathyrus sativus) on the flat areas were compared with the traditional practices. Yield and biomass data were obtained from research stations in the area whilst the effective rainfall and crop water requirement were estimated using CROPWAT Model. The feed value of the native grass and crop straw was estimated based on previous works. With respect to effective rainfall, the water productivity increase due to BBF over the control ranged from 5 to 200%, with an average increase of 57%. Despite higher water consumption of the rice, feeding its residues to livestock enhanced the overall economic water productivity of the system over the natural grazing or grasspea cultivation. Consequently, use of BBF enables growing high value or food crops of choice that may be sensitive to waterlogging whilst tolerant crops can be grown on flat lands allowing utilization of the full growing period. Coupled with livestock integration into the system, the alternatives can enhance food production and resource use efficiency from these ‘marginal’ areas

Enhancing farming system water productivity through alternative land use and water management in vertisol areas of Ethiopian Blue Nile Basin (Abay)

Until recently, the Ethiopian government's investment did not systematically target high potential areas for agricultural intensification, limiting the potential productivity gains. Waterlogged vertisols, which cover about 2.7 million hectares in the Ethiopian part of the Blue Nile Basin, are among the high potential soils where management interventions could result in positive impacts. This study utilized soil, climate, crop and livestock productivity data and models to demonstrate intensification strategies which can increase crop-livestock system productivity. To understand the effects of alternative land use and water management interventions on water productivity, the areas have been classified into three drainage status depending on slope classes. Accordingly, non-drainable (0–2%), drainable (2–5%) and naturally drained (>5%) respectively, represented areas where artificial drainage is not feasible, where drainage using broad bed and furrows (BBF) is recommended, and areas where waterlogging is not a problem and no intervention is needed. Early planting of wheat (Triticum spp.) on BBF instead of the traditional late planting on flat beds in drainable areas and rice (Oryza sativa) cultivation instead of the traditional extensive grazing or growing grass-pea (Lathyrus sativus) on the flat areas provide viable alternative cropping options. Yield data of the crops and biomass of the native grass were obtained from research stations in the area while the effective rainfall and crop water requirement were estimated using CROPWAT Model. The value of the native grass and crop straw as livestock feed was estimated based on previous works. With respect to effective rainfall, the water productivity increase due to BBF over the control ranged from 5% to 200%, with an average increase of 57%. Despite higher water consumption of rice, feeding its residues to livestock enhanced the overall economic water productivity of the system as compared to the natural grazing or grass-pea cultivation. This can be accounted for by higher rice biomass productivity and the greater demand for its grain. The study demonstrated that draining the excess water when the slope allows, growing suitable high value crops on non-drainable areas, and integration of livestock into improved land and water management enhance overall agricultural system water productivity

W(h)ither the academy? An exploration of the role of university social work in shaping the future of social work in Europe

A controversial proposal to pilot the training of child protection social workers through an intensive work-based route in England is being supported and funded by the UK Government. Frontline, the brainchild of a former teacher, locates social work training within local authorities (‘the agency’) rather than university social work departments (‘the academy’) and has stimulated debate amongst social work academics about their role in shaping the direction of the profession. As a contribution to this debate, this paper explores the duality of social work education, which derives its knowledge from both the academic social sciences and the experience of practice within social work agencies. While social work education has traditionally been delivered by the academy, this paper also explores whether the delivery of training in the allied professions of probation and nursing by ‘the agency’ is equally effective. Finally, this paper explores the Helsinki model which achieves a synergy of ‘academy’ and ‘agency’. It suggests that there are alternative models of social work education, practice and research which avoid dichotomies between the ‘academy’ and the ‘agency’ and enable the profession to be shaped by both social work academics and practitioners

Spitting Performance Parameters and Their Biomechanical Implications in the Spitting Spider, Scytodes thoracica

Spitting spiders Scytodes spp. subdue prey by entangling them at a distance with a mixture of silk, glue, and venom. Using high-speed videography and differential interference contrast microscopy, the performance parameters involved in spit ejection by Scytodes thoracica (Araneae, Scytodidae) were measured. These will ultimately need to be explained in biomechanical and fluid dynamic terms. It was found that the ejection of “spit” from the opening of the venom duct (near the proximal end of the fang) was orderly. It resulted in a pattern that scanned along a lateral-medial axis (due to fang oscillations) while traversing from ventral to dorsal (due to cheliceral elevation). Each lateral-to-medial sweep of a fang produced silk-borne beads of glue that were not present during each subsequent medial-to-lateral sweep. The ejection of “spit” was very rapid. A full scan (5–57 fang cycles, one upsweep of a chelicera) typically occupied less than 30 ms and involved fang oscillations at 278–1781 Hz. Ejection velocities were measured as high as 28.8 m/s. The “spit” was contractile. During the 0.2 s following ejection, silk shortened by 40–60% and the product of a full scan by both of the chelicerae could exert an aggregate contractile force of 0.1 – 0.3 mN. Based on these parameters, hypotheses are described concerning the biomechanical and fluid dynamic processes that could enable this kind of material ejection

Rapid Land Cover Map Updates Using Change Detection and Robust Random Forest ClassifiersRapid Land Cover Map Updates Using Change Detection and Robust Random Forest Classifiers

The paper evaluated the Landsat Automated Land Cover Update Mapping (LALCUM) system designed to rapidly update a land cover map to a desired nominal year using a pre-existing reference land cover map. The system uses the Iteratively Reweighted Multivariate Alteration Detection (IRMAD) to identify areas of change and no change. The system then automatically generates large amounts of training samples (n \u3e 1 million) in the no-change areas as input to an optimized Random Forest classifier. Experiments were conducted in the KwaZulu-Natal Province of South Africa using a reference land cover map from 2008, a change mask between 2008 and 2011 and Landsat ETM+ data for 2011. The entire system took 9.5 h to process. We expected that the use of the change mask would improve classification accuracy by reducing the number of mislabeled training data caused by land cover change between 2008 and 2011. However, this was not the case due to exceptional robustness of Random Forest classifier to mislabeled training samples. The system achieved an overall accuracy of 65%–67% using 22 detailed classes and 72%–74% using 12 aggregated national classes. “Water”, “Plantations”, “Plantations—clearfelled”, “Orchards—trees”, “Sugarcane”, “Built-up/dense settlement”, “Cultivation—Irrigated” and “Forest (indigenous)” had user’s accuracies above 70%. Other detailed classes (e.g., “Low density settlements”, “Mines and Quarries”, and “Cultivation, subsistence, drylands”) which are required for operational, provincial-scale land use planning and are usually mapped using manual image interpretation, could not be mapped using Landsat spectral data alone. However, the system was able to map the 12 national classes, at a sufficiently high level of accuracy for national scale land cover monitoring. This update approach and the highly automated, scalable LALCUM system can improve the efficiency and update rate of regional land cover mapping

Origin and function of stomata in the moss Physcomitrella patens.

Stomata are microscopic valves on plant surfaces that originated over 400 million years (Myr) ago and facilitated the greening of Earth's continents by permitting efficient shoot-atmosphere gas exchange and plant hydration(1). However, the core genetic machinery regulating stomatal development in non-vascular land plants is poorly understood(2-4) and their function has remained a matter of debate for a century(5). Here, we show that genes encoding the two basic helix-loop-helix proteins PpSMF1 (SPEECH, MUTE and FAMA-like) and PpSCREAM1 (SCRM1) in the moss Physcomitrella patens are orthologous to transcriptional regulators of stomatal development in the flowering plant Arabidopsis thaliana and essential for stomata formation in moss. Targeted P. patens knockout mutants lacking either PpSMF1 or PpSCRM1 develop gametophytes indistinguishable from wild-type plants but mutant sporophytes lack stomata. Protein-protein interaction assays reveal heterodimerization between PpSMF1 and PpSCRM1, which, together with moss-angiosperm gene complementations(6), suggests deep functional conservation of the heterodimeric SMF1 and SCRM1 unit is required to activate transcription for moss stomatal development, as in A. thaliana(7). Moreover, stomata-less sporophytes of ΔPpSMF1 and ΔPpSCRM1 mutants exhibited delayed dehiscence, implying stomata might have promoted dehiscence in the first complex land-plant sporophytes

Chewing Through the Miocene: An Examination of the Feeding Musculature in the Ground Sloth Hapalops from South America (Mammalia: Pilosa)

Hapalops, a smaller-sized and early sloth of the Megatheroidea, appeared in the middle Miocene Santa Cruz formation of Argentina. This genus is part of the group from which later, larger megatheroids arose, i.e., Nothrotheriops and Megatherium. Many cranial characters support this idea; however Hapalops is not merely a smaller antecedent of the later forms. Specifically, Hapalops retains short anterior caniniform teeth, and a temporomandibular joint elevated above the cheek tooth row; a combination distinct among sloths. An elevated temporomandibular joint occurs in Bradypus, a tree sloth with anterior chisel-shaped teeth instead of caniniforms, and the tree sloth Choloepus, which is aligned with the megalonychids, has anterior caniniforms. Hapalops has an elongated zygomatic ascending process that is reminiscent of that in Bradypus; however, the Bradypus skull is extremely foreshortened while that of Hapalops is elongated, as in nothrotheres, but not deepened as in megatheres. Previous work identified many sloth cranial character complexes, and functional limitations on skull feature combinations. The unique Hapalops character patterns indicate a selective feeder with a mediolaterally oriented grinding stroke during mastication

Constructing a climate change logic: An institutional perspective on the "tragedy of the commons"

Despite increasing interest in transnational fields, transnational commons have received little attention. In contrast to economic models of commons, which argue that commons occur naturally and are prone to collective inaction and tragedy, we introduce a social constructionist account of commons. Specifically, we show that actor-level frame changes can eventually lead to the emergence of an overarching, hybrid "commons logic" at the field level. These frame shifts enable actors with different logics to reach a working consensus and avoid "tragedies of the commons." Using a longitudinal analysis of key actors' logics and frames, we tracked the evolution of the global climate change field over 40 years. We bracketed time periods demarcated by key field-configuring events, documented the different frame shifts in each time period, and identified five mechanisms (collective theorizing, issue linkage, active learning, legitimacy seeking, and catalytic amplification) that underpin how and why actors changed their frames at various points in time-enabling them to move toward greater consensus around a transnational commons logic. In conclusion, the emergence of a commons logic in a transnational field is a nonlinear process and involves satisfying three conditions: (1) key actors view their fates as being interconnected with respect to a problem issue, (2) these actors perceive their own behavior as contributing to the problem, and (3) they take collective action to address the problem. Our findings provide insights for multinational companies, nation-states, nongovernmental organizations, and other stakeholders in both conventional and unconventional commons