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Gluconacetobacter diazotrophicus is a nitrogen fixing bacterium able to colonise a wide range of host plants and is marketed as a biofertiliser due to its ability to promote plant growth. This study aims to investigate how biological nitrogen fixation (BNF) competency affects the growth promotion of inoculated tomato plants and to describe the colonisation mechanism of this bacterium in dicot systems. A nitrogen fixation impaired mutant (Gd nifD-) was produced by disrupting the nifD gene, which encodes the nitrogenase Mo-Fe subunit, in order to assess its plant growth promotion (PGP) capability in comparison to G. diazotrophicus wild type strain (Gd WT). Furthermore, tagged strains were employed to monitor the colonisation process through qPCR analyses and fluorescence microscopy. Following a preliminary glass house trial, Gd WT or Gd nifD- were applied to hydroponically grown tomato plants under nitrogen-replete and nitrogen-limiting conditions. Bacteria reisolation data and plant growth parameters including height, fresh weight, and chlorophyll content were assessed 15 days post inoculation (dpi). Gd WT significantly enhanced plant height, fresh weight, and chlorophyll content in both nitrogen conditions, while Gd nifD- showed a reduced PGP effect, particularly in terms of chlorophyll content. Both strains colonised plants at similar levels, suggesting that the growth advantages were linked to BNF capacity rather than colonisation differences. These findings indicate that a functional nifD gene is a fundamental requirement for optimal plant growth promotion by G. diazotrophicus. [ABSTRACT FROM AUTHOR]

This document is an editorial from the International Journal of Environmental Studies titled "Editorial: Monograph: Rebuilding, Infrastructure & Cultural Heritage of Ukraine." It discusses the devastating impact of the war between Ukraine and Russia on the country's population, culture, infrastructure, and environment. The editorial highlights the destruction of cultural heritage, the loss of lives of Ukrainian writers and cultural leaders, and the need for psychological support to prevent the transmission of trauma to future generations. It also explores the challenges of rebuilding Ukraine's cities, the potential for renewable energy sources, the environmental consequences of the war, and the importance of regenerative agriculture in combating global heating and preserving the water cycle. The document emphasizes the urgent need for international support and investment in Ukraine's recovery efforts. The given text discusses various environmental issues in Ukraine, particularly those related to war and conflict. It highlights the impact of war on nitrogen and sulfur deposition in the Dniester catchment, as well as the destruction of the Kakhovka dam and its effects on water resources. The text also addresses the loss of fisheries and the decrease in soil fertility due to human activities. Additionally, it explores the potential solutions for these issues, such as conservation agriculture and the use of sewage sludge for crop growth. The text concludes by emphasizing the need to address the environmental consequences of war and protect Ukraine's flora and fauna. [Extracted from the article]

Greenhouse gases do not generate heat. Bare ground is the furnace: vegetation and the water cycle provide the air-conditioning. Heat is emitted as infrared radiation; greenhouse gases in the atmosphere absorb some of this outgoing radiation which then heats the atmosphere or is reabsorbed by the land and, mainly, the oceans. So, control of greenhouse gas emissions is necessary and urgent – but it will not be enough to arrest global heating and does nothing for the water cycle. Clearance of natural landscapes for agriculture has driven global heating and disrupted the water cycle. Regenerative agriculture combats these hazards by avoiding bare soil, not ploughing, adopting a diverse crop rotation including perennial grasses and legumes, and creating windbreaks and wetlands. Speedier uptake of these society-saving practices requires a new social contract. The war in Ukraine provides an opportunity as well as urgent need. [ABSTRACT FROM AUTHOR]

Truog, who had more interest in soil chemistry, summed up his survey experience as: 'For the most part, we got along with such commonly understood descriptive words as dark or light, tight or open, top-soil or subsoil, level or hilly, and sand, silt and clay. Kellogg had little time to get used to his new position: Marbut died in Harbin in August 1935 and Kellogg, only 32 years old, was appointed to succeed him. References 1 Marbut, C.F., 1924, Soils: Their Genesis and Classification (Madison WI: Soil Science Society of America, 1951). [Extracted from the article]

The reductionist approach to intensification of agriculture has created unanticipated economic, ecological and social consequences. Across the steppes, elimination of perennial legumes from the crop rotation and even elimination of crop rotation, large areas under black fallow, and the demise of crop and animal husbandry are draining soil fertility – and in many places loss of the soil itself. Data from long-term field experiments demonstrate the importance of perennial legumes in crop rotation for nitrogen- and water-use efficiency, accumulation of soil organic matter in deeper soil layers, and resilience in the face of drought.

Taking conservation to scale in complex systems: edited by Nick Salafasky and Richard Margoluis, Washington DC: Island Press, 2021, 328pp., $US29 (paperback) ISBN 978-1-64283-135-1 Messrs Salafasky and Margoluis distil what is challenging into what is comprehensible; explaining fundamental concepts of effective programme design, coordination, funding and stakeholder engagement that apply to large-scale conservation programmes. Integrating monitoring and analysis with implementation is a tenet of good management but the sole point in collecting and analysing data is to use the information to adapt and improve the programme. [Extracted from the article]

Why we have a moral responsibility to slow climate change right now: Henry Shue, Princeton and Oxford, Princeton University Press, 2022, 208 pp., £22.00/$27.95, ISBN 978069226248 (hbk), ISBN 978069226255 (e-book) Simply for power generation, renewables are now cheaper than fossil fuels and, yet, all the renewable energy is simply adding to that generated from fossil fuels: not substituting for it. The fossil-fuel energy regime and the measures necessary to make the transition into an alternative energy regime impact billions of people who have chosen neither the regime nor the transition, linking them across space to those who control the regime and the fate of the transition. [Extracted from the article]

Our purpose is a preliminary assessment of the effects of war in Ukraine on its soils. Realistic diagnosis demands details at the scale at which war operates. Lacking a soil map at this scale, and a new survey being out of the question, we modelled a predictive soil map of the whole country at scale 1:10,000. This enables accurate assessment of the areas of damage and the ecosystem services foregone. Mimicking personalised medicine and the precision-agriculture principle, farm by soil type, we can now set about healing by soil type – drawing on the particular resilience of particular soils and make allowance for their weaknesses too. For instance, chernozem have extraordinary resilience and self-healing capacity; a calcareous clay can fix radionuclides but peat soils have no such capacity. [ABSTRACT FROM AUTHOR]

Resource extraction defines our times: global exploitation of natural resources is doubling every decade to meet the needs and wants of a human population that has, itself, doubled since 1970. Expressions of violence and resistance: edited by Judith Shapiro and John-Andrew McNeish, Abingdon and New York, Earthscan:Routledge, 2021, xiv +255 pp., £34.99 (pbk), ISBN 978-0-367-65052-0 A new wave of the environmental justice movement - ExtrACTIVISM - focuses on resisting the extraction of resources on particular lands and on empowering local communities to win greater control over their fate. [Extracted from the article]

If 1000 years were required to melt the ice cap, the sea level would rise about 4 feet every ten years ... 100 times the present rate of sea level rise'. The report of his scientific advisory committee published in the same year suggested that one result could be'the melting of the Antarctic ice cap which would raise sea level by 400 feet. I An Andean glacier is melting: See you in court i is an account of a Peruvian farmer suing a German power utility for contributing to melting an Andean glacier that might bury his home with a cataclysmic mudflow, as happened earlier, in 1941. [Extracted from the article]

Food security and virtual water considerations continue to play out in the new geopolitics of food: after the global financial-food crisis of 2007/08, imports suddenly seemed tenuous and globalization created asymmetric trade interdependence that can be weaponized. The second part of this two-part special issue spans two decades of unprecedented change in society and the global economy that the water sector and water science have accommodated through the greatly increased role of the private sector and the evolution of the concept, practice and politics of the water-energy-food nexus. Tony Allan's final years of service focused on the issue of "under-priced food for under-paid people" embracing water accounting and governance in the food system; all unfinished business. [Extracted from the article]

Tony Allan graduated with a first in geography from Durham University in 1958, into a world very different from today. Finally, Mark Zeitoun leads a cohort of Tony Allan's former colleagues considering 'Power plus: Tony Allan's contributions to understanding transboundary water arrangements'. The 1990s: the political economy of water and virtual water Munther Haddadin's "Recollections of a peacemaker" record that Tony Allan became involved in the Middle East Peace Process in 1991 and the concept of virtual water, itself, has been a peacemaker. Tony Allan was always concerned whether any government of Libya would grasp the nature of the political economy of water security and invest accordingly. [Extracted from the article]

Soil is the biggest brake on global heating. It holds more carbon than the atmosphere and all standing vegetation together but farmers have been burning off soil organic matter for 12000 years: they are responsible for one-third of greenhouse gas emissions. The best thing they could do for the planet is to put it back again, and the best place to start is the best soil in the world – the Black Earth of the steppes, prairies and pampas. Half of its organic matter has been pumped into the air and 35 years of satellite measurements reveal a significant loss of primary productivity across the steppes. Conservation Agriculture can haul back the carbon deficit, increase yields and save 60–70% on fuel, fertiliser and labour; the green biomass can support livestock and/or generate biogas. Ukraine and Moldova were set to adopt this system and phase out their coal-fired power stations when the Russian army invaded Ukraine. The best soil in the world is now being put to other uses; we face a global food crisis; and the world's decision makers have yet another excuse to defer serious efforts to mitigate climate change. [ABSTRACT FROM AUTHOR]

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Rule 1: Be wary of rules It may be surprising that this is the first rule of a 10 simple rules article, but it is important to acknowledge that in something as important as career progression and research culture, there are no hard and fast rules. We can refocus this definition on the individual and define career entrepreneurship as the process of developing a career that results in increased value for the individual. As early career researchers our access to resources is limited, although perhaps paradoxically, a demonstration of how we have won personal research funding or managed research is often a requirement for career progression. [Extracted from the article]

Finding abundance, they slaughtered bison by the millions to exterminate the Plains Indians; they ploughed the sod and created the Dust Bowl; they found unlimited groundwater and pumped it dry; and they will leave a poisoned land. Lucas Bessire doesn't force any conclusions on us, but we might argue that, having arrived at some kind of explanation, we need to re-evaluate our cherished beliefs about the land, our neighbours and our governments. Aid, industrial farming and environmental collapse eroded the people too, and the discovery in the 1940s of the Ogalla aquifer tied Dust Bowl attitudes to groundwater depletion. [Extracted from the article]

When the MDBA called a public consultation in October 2010, the opposition was ready and waiting: the proceedings were vicious; copies of the Guide were burned on a bonfire; and the aggression, backed up by the National Party, eviscerated the MDBA. By devious means, this was achieved and the Water Act came into force along with a centrally appointed Murray-Darling Basin Authority (MDBA) to implement it. The Commonwealth Government and MDBA refused to participate; instead, they sued the Commissioner. [Extracted from the article]

To qualify for payments from the public purse, farmers will not only have to produce food but, also, demonstrate good stewardship by delivering public goods: arresting soil erosion, abating floods, recharging groundwater, mitigating global heating, etc. Moreover, discerning consumers seek guarantees of sustainable food production that are not provided by prices and labelling. The proposed Standard for Soil Health meets a felt need by comparing the condition of the soil with its potential capacity to grow crops and maintain environmental services. The criteria are ground cover, biological status represented by soil organic matter and physical status represented by bulk density – yardsticks that also reveal trends so credit may be given for improvement as well as inherent soil quality. [ABSTRACT FROM AUTHOR]

This article argues that the economic sanctions against Cuba do not serve US interests and thus should be discontinued. Both Presidents Eisenhower and Kennedy viewed Castro as a significant communist threat to the US. They imposed strict economic sanctions against his regime, hoping that Cuba's ties with the USSR would weaken and that the Castro regime would eventually collapse under economic strain. To the vexation of US officials, the opposite occurred as Cuba was pushed directly into the USSR's political and economic orbit, as the Soviets came to Cuba's aid to soften the impact of the sanctions. Moreover, the economic sanctions strengthened the resolve of the Cuban people to stand up to America, their imperialist aggressor. While attempts were made in the mid 1970's to lift the embargo, US officials felt that doing so would be too apparent of a mea culpa and thus would harm the US's image as an avid champion of democracy and capitalism. Although lifting the embargo would symbolize the end of US hegemony in the Western hemisphere, America has much to gain from doing so. [ABSTRACT FROM AUTHOR]

Land degradation is a global issue on par with climate change and loss of biodiversity, but its extent and severity are only roughly known and there is little detail on the immediate processes – let alone the drivers. Earth-observation methods enable monitoring of land degradation in a consistent, physical way and on a global scale by making use of vegetation productivity and/or loss as proxies. Most recent studies indicate a general greening trend, but improved data sets and analysis also show a combination of greening and browning trends. Statistically based linear trends average out these effects. Improved understanding may be expected from data-driven and process-modelling approaches: new models, model integration, enhanced statistical analysis and modern sensor imagery at medium spatial resolution should substantially improve the assessment of global land degradation. [ABSTRACT FROM AUTHOR]

Land degradation is a global development and environment issue that afflicts China more than most countries in terms of the extent, economic impact, and number of people affected. Up-to-date, quantitative information is needed to support policy and action for food and water security, economic development, and environmental integrity. Data for a defined, recent period enable us to distinguish the legacy of historical land degradation from what is happening now. We define land degradation as long-term decline in ecosystem function and productivity and measure it by remote sensing of the normalized difference vegetation index (NDVI), the greenness index. NDVI may be translated to net primary productivity (NPP). Deviation from the norm serves as a proxy assessment of land degradation and improvement--if other factors that may be responsible are taken into account. These other factors include climate, which may be assessed by rain- use efficiency and energy-use efficiency. Analysis of the 23-year Global Inventory Modeling and Mapping Studies (GIMMS) NDVI data reveals that, in China over the period 1981-2003, NPP increased overall, but areas of declining climate-adjusted NPP comprise 23% of the country, mainly in south China. About 35% of China's population (457 million out of 1 317 million) depend on the degrading land. Degrading areas suffered a loss of NPP of 12 kgC ha-1 y-1 , amounting to almost 60 million tC not fixed from the atmosphere; loss of soil organic carbon from these areas is likely to be orders of magnitude greater. There is no correlation between land degradation and dry lands; it is more of an issue in cropland and forest: 21% of degrading land is cropland and 40% is forest, 24% of the arable and 44% of the forest, respectively. There is no simple statistical relationship between land degradation and rural population density or poverty. Most identified land degradation is in the south and east, driven by unprecedented land-use change. [ABSTRACT FROM AUTHOR]

Recent studies have suggested that progestogen-only contraceptives and combined estrogen/progestogen oral contraceptives (COCs) may increase the risk of breast cancer among women less than 35 years of age or among recent users, The authors conducted a case-control study, in which cases of breast cancer (n = 419) and controls (n = 1,625) hospitalized for conditions unrelated to contraceptive use were interviewed from 1994 to 1997 in hospitals in greater Cape Town, South Africa. The women were aged 20–54 years, resided in a defined area around Cape Town, and were Black or of mixed racial descent. The relative risk for exposure to injectable progestogen contraceptives (IPCs), mostly depot medroxyprogesterone acetate, was 0.9 (95% confidence interval (CI) 0.7, 1.2). There were no consistent associations within categories of age or recency or duration of use. For exposure to COCs, the overall relative risk was 1.2 (95% CI 1.0, 1.5). Among women below age 35 years, the relative risk was 1.7 (95% CI 1.0, 3.0), and it was unrelated to the duration or recency of use. The findings suggest that IPCs do not increase the risk of breast cancer, and that COCs may increase the risk among women below age 35 years, although bias cannot be excluded. Am J Epidemiol 2000;151:396–403. [ABSTRACT FROM PUBLISHER]

Menetrier’s disease is a rare condition characterized by marked proliferation of gastric mucosa with variable mucus secretion and achlorhydria. Although crude mucus secretion and gastric aspirates have been evaluated in this disease for output of dry matter, hexosamine, fucose, protein content, and transforming growth factor α activity, we report for the first time the isolation, purification, and gel electrophoresis of mucin from crude mucus scrapings. The fragmentation pattern of mucin in Menetrier’s disease demonstrated less large polymeric mucin than the control. There was also a band of ∼55–65 kd Mr on polyacrylamide gel electrophoresis similar to that found in gastric carcinoma or peptic ulcer, but absent in the control specimens. [Copyright &y& Elsevier]

Background/Aims: Gastric cancer, a fatal malignancy, is prevalent in the Western Cape region of South Africa. The aim of this study was a biochemical characterisation of gastric mucins in this disease, compared with gastric ulceration and controls from transplant donors. Methods: Mucins were extracted in a denaturing medium (to prevent endogenous proteolysis) and purified by caesium chloride density gradient ultracentrifugation. Analysis of mucin was by gel filtration, SDS-PAGE and Western blotting methods. Results: All samples of mucin when analysed by gel filtration were found to contain polymeric glycoprotein together with varying amounts of lower-molecular-weight glycoprotein. SDS-PAGE and Western blot analysis showed that diseased stomachs had glycopeptides of a wider range in size and antigenicity with a greater number of smaller fragments immunoreactive to monoclonal antibodies 2–12M1 and 9–13M1. We identified by SDS-PAGE a glycoprotein which co-fractionates in a caesium chloride density gradient with mucins isolated from gastrectomy specimens resected for carcinoma and peptic ulceration and which was absent from mucins of the transplant donor control group. This neuraminidase-sensitive glycoprotein resisted dissociation from mucin during purification in a 3.5 M CsCl density gradient but was partially separable by Sepharose 2B gel chromatography and heat treatment (100°C, 2.0 min) in SDS. Chemical analysis of the glycoprotein by HPLC favours it being an N-linked glycoprotein. Its non-ideal electrophoretic properties make its exact size estimation difficult and we ascribe to it a broad size range of M[sub r] ∼55–65 kD. Conclusion: We conclude that mucins from diseased stomachs were more degraded than those from donors and that the diseased mucosa reproducibly secretes a M[sub r] ∼55–65 kD glycoprotein, the role of which needs to be established. [ABSTRACT FROM AUTHOR]