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The expansion of irrigated agriculture has increased global crop production but resulted in widespread stress to freshwater resources. Ensuring that increases in irrigated production only occur in places where water is relatively abundant is a key objective of sustainable agriculture, and knowledge of how irrigated land has evolved is important for measuring progress towards water sustainability. Yet a spatially detailed understanding of the evolution of global area equipped for irrigation (AEI) is missing. Here we utilize the latest sub-national irrigation statistics (covering 17298 administrative units) from various official sources to develop a gridded (5 arc-min resolution) global product of AEI for the years 2000, 2005, 2010, and 2015. We find that AEI increased by 11% from 2000 (297 Mha) to 2015 (330 Mha) with locations of both substantial expansion (e.g., northwest India, northeast China) and decline (e.g., Russia). Combining these outputs with information on green (i.e., rainfall) and blue (i.e., surface and ground) water stress, we also examine to what extent irrigation has expanded unsustainably (i.e., in places already experiencing water stress). We find that more than half (52%) of irrigation expansion has taken place in regions that were already water stressed, with India alone accounting for 36% of global unsustainable expansion. These findings provide new insights into the evolving patterns of global irrigation with important implications for global water sustainability and food security. Recommended citation: Mehta, P., Siebert, S., Kummu, M. et al. Half of twenty-first century global irrigation expansion has been in water-stressed regions. Nat Water (2024). https://doi.org/10.1038/s44221-024-00206-9 Open-access peer reviewed publication available at https://www.nature.com/articles/s44221-024-00206-9 Files G_AEI_*.ASC were produced using the GMIA dataset[https://data.apps.fao.org/catalog/iso/f79213a0-88fd-11da-a88f-000d939bc5d8]. Files MEIER_G_AEI_*.ASC were produced using Meier et al. (2018) dataset [https://doi.pangaea.de/10.1594/PANGAEA.884744].

The development of technologies for utilizing biomass has attracted attention because biomass can be produced sustainably worldwide. Biomass-derived 2-methyltetrahydrofuran (MTHF), which is a promising alternative to gasoline, has great market potential and a growing demand. However, in conventional biomass conversion processes, the minimum selling price (MSP) of biochemicals is not economically acceptable. Co-production of biochemicals can increase the economics of biomass utilization. Herein, we developed a process for coproducing MTHF and 1,4-pentanediol (1,4-PDO) from lignocellulosic biomass. After biomass fractionation, cellulose and hemicellulose were converted to levulinic acid (LA), and lignin was used for heat and electricity generation. LA was then converted to γ-valerolactone (GVL). As a platform material for co-production, GVL was converted into MTHF and 1,4-PDO in each subsystem. The split ratio of GVL was controlled to efficiently produce MTHF and 1,4-PDO according to market conditions. Additionally, we performed a techno-economic and life-cycle assessment (TEA and LCA, respectively) for the developed process. The MSP of MTHF was calculated based on the TEA results, and the environmental impacts were quantitatively calculated based on the LCA results. We performed heat integration using pinch analysis and then reduced the energy requirement of the proposed process. The key cost drivers and environmental factors of the proposed process were identified via sensitivity analyses. Consequently, during the processing of 2,000 ton/day of corn stover (raw material of lignocellulose), the MSP of MTHF was calculated as $2.64/GGE (gasoline equivalent), and representative environmental impacts such as climate change and fossil depletion were calculated as -0.296 kg CO2 eq and -0.056 kg oil eq, respectively. As a result, we can increase the economics of commercial production of MTHF and 1,4-PDO with environmental sustainability. The proposed process can serve as a potential solution to the growing demand for the need for more sustainable biomass utilization.

The productivity and demand of wax in the world market has been reviewed. The production and consumption of wax, candle and ranking of manufactures in the world market have also been discussed. The production capacity and importance of quantity of Chinese wax have also been a matter of evaluation. The complete development of wax products has resulted in good economic and social benefits around the world. European Chemical Bulletin, Vol 1, No 7 (2012): European Chemical Bulletin

Waste heat recovery is an important way to improve the energy utilization efficiency and protect the environment. Waste heat power generation is one of the ways. In this paper a new power generation device that different from the screw expanding power generation and Organic Rankine cycle power generation named Roots-steam generator is designed to use the low-pressure saturated steam that pressure below 1 MPa and temperature below 200°C. One 100 Kw (Kilowatt) Roots-steam generator was designed to do the related experiment and the results show that the Roots- steam generator can use the steam that pressure is less than 0.3 MPa, flow less than 0.15 t/h(tons per hour) to generate electricity.

This research analyzed the effects of forestland conversion from private to public ownership on greenhouse gas emissions by quantifying the relationship between forestland ownership conversion and deforestation, and then examining the effects of the change in deforestation on greenhouse gas emissions in South Korea. Ex ante simulations forecast greenhouse gas emissions resulting from deforestation rates under the current level of national forestland and three scenarios of increased percentages of national forestland. The findings suggest that increasing the percentage of national forestland would mitigate the increase in the deforestation rate, which in turn would moderate the increase in greenhouse gas emissions.

Suggested citation: Pörtner, H.O., Scholes, R.J., Agard, J., Archer, E., Arneth, A., Bai, X., Barnes, D., Burrows, M., Chan, L., Cheung, W.L., Diamond, S., Donatti, C., Duarte, C., Eisenhauer, N., Foden, W., Gasalla, M. A., Handa, C., Hickler, T., Hoegh-Guldberg, O., Ichii, K., Jacob, U., Insarov, G., Kiessling, W., Leadley, P., Leemans, R., Levin, L., Lim, M., Maharaj, S., Managi, S., Marquet, P. A., McElwee, P., Midgley, G., Oberdorff, T., Obura, D., Osman, E., Pandit, R., Pascual, U., Pires, A. P. F., Popp, A., Reyes-García, V., Sankaran, M., Settele, J., Shin, Y. J., Sintayehu, D. W., Smith, P., Steiner, N., Strassburg, B., Sukumar, R., Trisos, C., Val, A.L., Wu, J., Aldrian, E., Parmesan, C., Pichs-Madruga, R., Roberts, D.C., Rogers, A.D., Díaz, S., Fischer, M., Hashimoto, S., Lavorel, S., Wu, N., Ngo, H.T. 2021. IPBES-IPCC co-sponsored workshop report on biodiversity and climate change; IPBES and IPCC, DOI:10.5281/zenodo.4782538 This report presents the main conclusions of the first-ever IPCC-IPBES co-sponsored workshop which took place in December 2020. The workshop explored diverse facets of the interaction between climate and biodiversity, from current trends to the role and implementation of nature-based solutions and the sustainable development of human society. This report is underpinned by the Scientific Outcome, which includes seven sections, the complete references and the report glossary. You can find the Scientific Outcome here https://doi.org/10.5281/zenodo.4659158

The Amazon rainforest regulates the global temperature and is one of the most biodiverse places on Earth. Nonetheless, deforestation, land-use changes, monoculture, large distances from community to community, limited agriculture production and climate change effects present substantial obstacles for the region. In addition, many Amazonian indigenous communities suffer from energy poverty and lack regular access to electricity, proper wastewater treatment as well as adequate residue management. Sustainable energy solutions based on biowaste might help Amazonian communities manage both environmental and socioeconomic concerns. The goal of this research is to figure out if biowaste could be used by Amazonian communities as a source of renewable energy. Biowaste consists of organic materials that can produce biogas and biofuels, such as agricultural residues, animal waste, and food manure. Then, the environmental and social implications of biowaste-based renewable energy plants in the Amazon Region of Ecuador were assessed, which look to counteract the fossil fuel dependence. This type of study illustrates the potential for biowaste-based energy alternatives to provide rural communities with affordable energy while lowering greenhouse gas emissions and promoting sustainable land use. It was concluded that biowaste-based renewable energy alternatives have the potential to alleviate both the environmental and socioeconomic concerns facing Amazonian communities. Government policy, community technical training, and project monitoring for biochemical and thermal projects should all support it. By redefining biowaste-based renewable energy, it is possible to encourage sustainable development in the region while protecting the Amazon rainforest's vital ecosystem services.

Bioenergy is currently regarded as a renewable energy source with a high growth potential. Forest-based biodiesel, with the significant advantage of not competing with grain production on cultivated land, has been considered as a promising substitute for diesel fuel by many countries, including China. Consequently, extracting biodiesel from <em>Jatropha</em><em> curcas</em> has become a growing industry. However, many key issues related to the development of this industry are still not fully resolved and the prospects for this industry are complicated. The aim of this paper is to evaluate the net energy, CO₂ emission, and cost efficiency of <em>Jatropha</em> biodiesel as a substitute fuel in China to help resolve some of the key issues by studying data from this region of China that is well suited to growing <em>Jatropha</em>. Our results show that: (1) <em>Jatropha</em> biodiesel is preferable for global warming mitigation over diesel fuel in terms of the carbon sink during <em>Jatropha</em> tree growth. (2) The net energy yield of <em>Jatropha</em> biodiesel is much lower than that of fossil fuel, induced by the high energy consumption during <em>Jatropha</em> plantation establishment and the conversion from seed oil to diesel fuel step. Therefore, the energy efficiencies of the production of <em>Jatropha</em> and its conversion to biodiesel need to be improved. (3) Due to current low profit and high risk in the study area, farmers have little incentive to continue or increase <em>Jatropha</em> production. (4) It is necessary to provide more subsidies and preferential policies for <em>Jatropha</em> plantations if this industry is to grow. It is also necessary for local government to set realistic objectives and make rational plans to choose proper sites for <em>Jatropha</em> biodiesel development and the work reported here should assist that effort. Future research focused on breading high-yield varieties, development of efficient field management systems, and detailed studies lifecycle environmental impacts analysis is required to promote biologically and economically sustainable development of <em>Jatropha</em> biodiesel and to assist government agencies in setting realistic objectives and appropriate and advantageous policies for the regions and the country.