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This paper develops a strategy for the continuing and improved supply of woodfuels to urban and industrial consumers in Sub-Sahara Africa. It argues that continued use of these fuels is not only a necessity, but is also in the best economic interest of most of the countries in this region. It shows that intensified and more orderly utilization of woodfuels can help to enhance, rather than impinge upon environmental parameters. Some examples are provided that illustrate how such strategies can be put into practice.

AbstractChina is under pressure to improve its agricultural productivity to keep up with the demands of a growing population with increasingly resource‐intensive diets. This productivity improvement must occur against a backdrop of carbon intensity reduction targets, and a highly fragmented, nutrient‐inefficient farming system. Moreover, the Chinese government increasingly recognizes the need to rationalize the management of the 800 million tonnes of agricultural crop straw that China produces each year, up to 40% of which is burned in‐field as a waste. Biochar produced from these residues and applied to land could contribute to China's agricultural productivity, resource use efficiency and carbon reduction goals. However competing uses for China's straw residues are rapidly emerging, particularly from bioenergy generation. Therefore it is important to understand the relative economic viability and carbon abatement potential of directing agricultural residues to biochar rather than bioenergy. Using cost‐benefit analysis (CBA) and life‐cycle analysis (LCA), this paper therefore compares the economic viability and carbon abatement potential of biochar production via pyrolysis, with that of bioenergy production via briquetting and gasification. Straw reincorporation and in‐field straw burning are used as baseline scenarios. We find that briquetting straw for heat energy is the most cost‐effective carbon abatement technology, requiring a subsidy of $7 MgCO2e−1 abated. However China's current bioelectricity subsidy scheme makes gasification (NPV $12.6 million) more financially attractive for investors than both briquetting (NPV $7.34 million), and pyrolysis ($−1.84 million). The direct carbon abatement potential of pyrolysis (1.06 MgCO2e per odt straw) is also lower than that of briquetting (1.35 MgCO2e per odt straw) and gasification (1.16 MgCO2e per odt straw). However indirect carbon abatement processes arising from biochar application could significantly improve the carbon abatement potential of the pyrolysis scenario. Likewise, increasing the agronomic value of biochar is essential for the pyrolysis scenario to compete as an economically viable, cost‐effective mitigation technology.

Exploring the sensitivity of rural households’ livelihood strategies to livelihood capital is of great significance for improving rural households’ livelihood levels. This paper selects 23 livelihood capital measurement indicators and conducts an in-depth survey of rural households. In addition, the entropy method and a weighted comprehensive model are used to explore the basic characteristics of rural households’ livelihood capital in the upper reaches of the Min River, China, in 2017. Furthermore, econometric models are used to analyze the sensitivity of rural households’ livelihood strategies to livelihood capital. As indicated from the research, the livelihood capital levels of different types of rural households in the study area are not equivalent. The types of rural households with different livelihood strategies can be ordered in terms of quantity as follows: non-agricultural type > non-agricultural dominant type > agricultural dominant type > pure agricultural type. Livelihood strategies have different sensitivities to different livelihood capital measurement indicators. Among these indicators, cash income, the number of relatives and friends available for financial assistance, and the number of civil servants have positive effects on the livelihood strategy selection of non-agricultural dominant rural households and non-agricultural rural households. However, the average age of laborers, area of cultivated land and gardens, number of livestock and poultry, and present value of production tools have negative effects. These evaluation results can provide a scientific decision-making basis for the formulation of poverty alleviation policies by relevant government departments.

Promoting biodiesel industrialization is not only an important measure in addressing the energy crisis and global warming but is also a driver for industrial restructuring and rural development. To...

Abstract Sweet sorghum, a C4 plant, is known to be a unique, versatile, and potential energy crop that can be separated into starchy grains, soluble sugar juice, and lignocellulosic biomass. The fermentable sugars in the juice (53–85% sucrose, 9–33% glucose, and 6–21% fructose) can be directly fermented into ethanol. The grain is primarily starch (62–75%), which can be hydrolyzed and fermented into ethanol. The bagasse, a fibrous lignocellulosic material, can be used to produce cellulosic ethanol, heat and/or power co-generation. In this review, the potential of sweet sorghum for bioenergy production (of various forms) using recently developed cultivars with improved agronomic performance was discussed. In addition, sweet sorghum was compared with other starch, sugar, and lignocellulosic feedstocks. Studies have been conducted on alternative pathways to convert whole sweet sorghum stalks and bagasse into bioenergy. However, very little review of the techno-economic analysis of bioenergy production and co-products from sweet sorghum has been published. The aim of this research was to review the current knowledge of agronomic requirement for cultivating sweet sorghum, the productivity of recently developed cultivars for bioenergy production, and pathways of converting sweet sorghum crop into bioenergy as well as the techno-economic feasibility of using sweet sorghum for bioenergy.

Abstract A hydrocarbon miscible flood was initiated in the Wizard Lake D-3A pool in late 1969. The scheme involved placing a slug of LPG at the gas-oil interface, and displacing it vertically downward with dry gas while injecting water to stabilize the oil-water contact. Ultimate recovery is expected to be 323 million stock tank barrels, 84per cent of the original oil-in-place and 69 million stock tank barrels higher than under primary depletion. The Wizard Lake D-3A pool, located in central Alberta, is one of nine Devonian reef pools connected to the Cooking Lake aquifer. It is a dolomitized bioherm reef with a maximum original oil zone of 648 feet. The pool was considered an ideal candidate for a miscible displacement process because of its vertical relief, small areal extent and the absence of any barriers that would be detrimental to displacement of the slug. This paper reviews the implementation, monitoring techniques and performance of the miscible flood scheme. Introduction The Wizard Lake D-3A pool, located 55 kilometres (35 miles) southwest of Edmonton, as shown in Figure 1, was discovered in April 1951 with the drilling of Texaco Wizard Lake Crown 'B-I in 12-22-48-27-W4M. The pool, drilled on 4D-acre spacing, was fully delineated by the late nineteen fifties. The reservoir is a dolomitized bioherm reef of Devonian age which is part of a prolific chain of Leduc member reefs appropriately known as the Golden Trend. The productive horizon attained a maximum recorded height of 197.5 metres (648 feet) above the Cooking Lake aquifer in which reef growth was initiated. The Cooking Lake aquifer pinches out to the west, but is extensive in the other three directions. This aquifer is very active and is common to other oil and gas accumulations which give rise to interference between pools (Figures 2 and 3). The oil column covered an area of 1,507 hectares (3,725 acres) at the original oil-water contact of 1,230 metres subsea (4,034 feet subsea). Figure 4 presents a structure contour map of the top of the pool based on the gross reef section. The initial oil-in-place is estimated to be 61,200,000 m3 (385 MMSTB), with some 6.5 × 109 m3 (231 bcf) of solution gas dissolved in it. The primary recovery mechanism, identified as a combination of gas expansion, water drive and gravity segregation, was allowed to continue until 1969, when a slug-type hydrocarbon miscible scheme was initiated (Fig. 5). In 1965, a secondary gas cap began to form and by the end of 1969 there existed a 24-metre (78-foot) gas column containing approximately 152 × 106 m3 (5.4 Bcf). Also, by 1969 the oil-water contact had risen by 15 metres (50 feet); leaving an relatively small quantity of available core and thus a method had to be developed to Overcome this shortcoming and also handle the edge effect on porosity that is characteristic of reef pools(1).

Summary An aquifer-influence function (AIF) can be calculated from a gas reservoir's production and pressure histories. The AIF is unique for an aquifer and can be analyzed to determine aquifer size and other information. Two AIF type curves were developed for aquifers with partially sealing faults and then applied to 32 U.S. gulf coast gas reservoirs.

Facing the non-point source pollution caused by fertilizer loss, study on the agricultural factors that have an influence on fertilizer reduction could provide a basis for the implementation of policies on fertilizer reduction control. Based on the panel data during 2002-2016 with cumulative contribution model and Log-Mean Divisia Index (LMDI), this paper innovatively comes up with reduction driving functions (including agricultural scale, intensification, fertilizer utilization, and labor productivity), studies the cumulative contribution rate and driving factors of fertilizer reduction in county units of Zhejiang Province. Main conclusions are: (1) 37 of 63 county units (58.73%) showed decreased in fertilizer application; top five county units contributed 50+%; top county units that contribute to fertilizer reduction are in plain area in Northern Zhejiang, coastal area in Eastern and Southern Zhejiang, valley and basin area in Western and Southern Zhejiang where arable land is relatively even. (2) Fertilizer application intensity (fertilizer application per unit area of land cultivation) in Zhejiang Province increased by 18.67%, but there are only 15 county units where fertilizer application intensity is reduced. In general, fertilizer reduction in Zhejiang Province kept developing steadily. (3) Factors (fertilizer efficiency, intensification and agricultural scale) drive fertilizer reduction while labor productivity triggers the growth in application intensity. In Hangzhou, Ningbo and Shaoxing in Northern and Eastern Zhejiang, the above factors all have a prominent driving effect, but labor productivity also promotes fertilizer increment. In the end, this paper proposes policies on fertilizer reduction control in terms of efficiency, inputs and compensations.

AbstractIncreasing resource scarcity and what has been called “the end of cheap nature” are prompting policymakers and scholars to foster more circular economies to reduce waste and lengthen the lifespan of material goods. Our essay critically examines the political and economic relationships between urban and rural geographies in the context of secondhand economies. Practices of bartering, swapping, selling, and repairing used goods have long been important to rural people and places, but the increasing commodification of discards risks upending rural livelihoods and ways of being as goods move toward urban centers. We explore the relationship between rural and urban reuse economies and suggest how future scholars of rural North America might contribute to strengthening and supporting localized reuse practices.