Environmental regulation, land use efficiency and industrial structure upgrading: Test analysis based on spatial durbin model and threshold effect

Environmental regulation promotes industrial structure change and regional economic transformation through land use adjustment, which gets a new way to explore the path of reforming traditional industrialization and urbanization. Based on the panel data of 128 prefecture-level cities in China 's Yangtze River Economic Belt from 2000 to 2020, this paper uses the spatial Dubin model to analyze the impact of environmental regulation and land use efficiency on the upgrading of industrial structure, and sets the panel threshold model to examine the impact of environmental regulation on the upgrading of industrial structure by affecting land use efficiency. The results show that formal environmental regulation has a significant positive spatial effect on the rationalization and upgrading of industrial structure, which are 0.1734 and 0.2854 respectively. Informal environmental regulation has a negative spillover effect on neighboring provinces but not significant. Heterogeneous environmental regulation has obvious "double threshold effect" on industrial upgrading by affecting land use efficiency. When the threshold of environmental regulation intensity is 0.0315-0.0886, environmental regulation still inhibits land use efficiency and industrial structure upgrading. When the threshold value is greater than 0.0886, environmental regulation has a positive impact on land use efficiency but not significant. With the intensity of environmental regulation from weak to strong, it will produce a double threshold effect of "strong inhibition-weak inhibition-interaction promotion" on the upgrading of manufacturing structure through the adjustment of land use efficiency.

Rethinking industrial land-use in American rust cities towards sustainability based on a block-level model

Urban land is a fundamental but scarce resource that carries intensive human socio-economic activities. The demographic decline and housing vacancy issues that emerged with de-industrialization have raised concerns regarding the sustainable utilization of urban land resources, particularly in the American Rust Belt region. In this context, a comprehensive analysis of industrial land use can offer valuable insights to support the sustainable planning of shrinking cities. However, existing urban land research exhibits insufficient resolution at the sectoral scale and impedes the evaluation of industrial land use efficiency within the urban context. To address this gap, we established an integrated land use estimation framework for economic sectors based on multi-source data, which enables the assessment of land use efficiency at a finer sectoral scale. The method was then applied to the city of Detroit, Cleveland, and Pittsburgh. The results demonstrate that the current industrial land mix in the three cities is dominated by service-providing industries, but the land usage by goods-producing sectors in these cities presents a relatively high level of efficiency. The Moran's I value indicates a clustered tendency for the main economic sectors. The land use area results reveal that Other Services occupies the most land area in Detroit (2.29 million m2) and Cleveland (2.04 million m2). While in Pittsburgh, Professional Scientific and Technical Services (1.44 million m2) is the largest. In terms of the economic output, Management of Companies and Enterprises is the most efficient sector in Detroit (20.28 thousand $/m2) and Cleveland (29.43 thousand $/m2), while Pittsburgh's Public Administration (11.73 thousand $/m2) is the most efficient. As many other cities in the world are about to enter the era of de-industrialization or low growth, the outcomes can also serve as a reference to guide their sustainable revitalization in line with the SDGs.

Reveal the inequality hidden in industry land use by integrating domestic trade and the industry efficiency

Although industrial land accounts for a low percentage of the land surface, it can significantly affect the development of the economy and the environment. Unbalanced development makes industry efficiency differ vastly across China. Industry products embodied in domestic trade link the indirect use of industry inputs and outputs. Regional inequality needs to be more scientifically checked by comprehensively considering both trade and the efficiency, which may be determined by diverse indices. Accordingly, this study examined industrial land use among provinces and the efficiency, identified the embodied land, developed approaches to ascertain how industrial land use would change without domestic trade, and revealed the inequalities in industrial land by considering the trade. Results found that provinces along China's coastline usually have a highly industrialised area, and the developed regions usually have high efficiency. Guangdong, Henan, Jiangsu, Shanghai, Shandong, Liaoning, Anhui, Hebei, and Heilongjiang have high values in both industrial land serving external provinces and the reverse use in external provinces. Through domestic trade, China saved a total of 462 km2 of land to be converted into industrial land, which is mainly due to developed regions providing industrial land use to undeveloped regions with low efficiency. The inequality analysis shows that most provinces were in a moderate state. Heilongjiang, Gansu, and Guangxi have obvious disadvantages. Some suggestions have been made for harmonious industry development and enhanced efficiency, such as the implementation of efficiency and price-based land use policies, industry and energy structure optimisation, technological improvement, and appropriate compensation.

A non-traditional Agrophotovoltaic installation and its impact on cereal crops: A case of the BRRI-33 rice variety in Bangladesh

Traditional Agrophotovoltaic (APV) installation (i.e., basic row layout with minimum or no usage of the space underneath the solar PV panels) is responsible for a vast amount of agricultural land waste as no regular crops are grown under the shade of APV. Bangladesh is no exception to this trend. A primary in-person survey of about 50 solar irrigation pumps (SIPs), i.e., APVs, in Bangladesh, shows that on average, 13.77 decimal or 7,200 sq.ft. of land is used for each APV system installation. If 10,000 SIPs are installed by 2027 in Bangladesh, as targeted by the government through Infrastructure Development Company Limited (IDCOL) by employing the same procedure, the land wastage would be 1,652 acres. Notably, this is a critical issue for a country like Bangladesh with a scarcity of agricultural lands. According to World Bank data, agricultural land in Bangladesh was about 80% in 1989 and reduced to 76% in 2020 due to population growth and urbanization. Therefore, to reduce agricultural land waste a non-traditional APV installation procedure, along with its shading impact on the BRRI-33 rice variety (a major crop in Bangladesh), has been investigated in this study. The results show that discontinuous sunlight has an insignificant impact on BRRI-33 rice production, and APV might be installed in the cultivating area for irrigation purposes. This non-traditional APV installation has a statistically insignificant impact on rice yield. For instance, the 100 grains' yield variation was between 1.45 and 4.82%, which is insignificant. Additionally, the APV shade does not negatively impact soil p^H level, and shadow helps keep the soil temperature low and ensures less irrigation. Hence, the proposed non-traditional APV installation could achieve sustainable agriculture and energy development through efficient land use at least in the case of the BRRI-33 rice variety.

Do farmers use waterlogged wastelands efficiently? An economic study on water chestnut farming in Bangladesh

Waterlogging due to rain-fed floods is considered a natural calamity worldwide that causes lands in the north region of Bangladesh to remain underwater and uncultivable for most crops during the rainy season. This unused wasteland has immense potential for additional earnings for the marginal farmer by converting it to cultivable land through proper utilization by cultivating water chestnuts. Increasing the productivity and efficiency of water chestnut farming in these wastelands would facilitate higher food production for the growing populations. Therefore, this study estimates the farmers' profitability of water chestnut production along with technical efficiency (TE) and land use efficiency (LUE). Primary data from 150 farmers of Natore, Naogaon, and Jamalpur districts were used and stochastic frontier analysis was employed. Results reveal that no farmers had any training in water chestnut farming. Human labor and land use costs incur more than 80% of the total cost and laborers shortage was found due to skin problems working in the water. However, water chestnut farming was profitable in all districts and the average benefit-cost ratio was 1.37. TE results indicate that there was an opportunity to increase the water chestnut production by 20.2% using the same amount of inputs. LUE by the water chestnut farmers was found to be very low; hence, they were using their land inefficiently and this inefficiency was positively affected by farm size and number of family members and negatively affected by age, year of schooling, and income. The study suggests research focusing on improved management of water chestnut without affecting laborers and training to facilitate higher productivity and LUE.

Exploring the impact of urban form on urban land use efficiency under low-carbon emission constraints: A case study in China's Yellow River Basin

In the Urban Anthropocene, how to meet the demands of growing urban populations on limited urban land is a key global challenge. Unreasonable urban planning and land use has brought about undesirable consequences including huge carbon emissions. However, research on the spatial impact of urban form on urban land use efficiency (ULUE) under low-carbon emission constraints is limited. This study analyzes 91 cities located in China's Yellow River Basin (YRB). First, we define a new comprehensive indicator system to measure ULUE under low-carbon constraints using the SBM-UN model. We then select nine landscape indicators to quantify the sprawl, complexity, and aggregation of urban form. Finally, we use Spatial Durbin Model to reveal the relationship between urban form and ULUE. We find that carbon emissions in the YRB increased steadily during the study period. The average value of ULUE increased from 0.469 in 1994 to 0.772 in 2018. Efficiency improved most in the provinces of Shaanxi, Henan, Ningxia, and Shandong, with growth rates of 234.15%, 102.40%, 93.09%, and 66.24%, respectively. Positive global Moran's I indices suggest that the spatial distribution of ULUE is positively correlated at basin level. Moreover, urban form metrics in the YRB demonstrated significant regional differences from 1994 to 2018. The regression results showed irregular urban form can negatively impact ULUE while compact and aggregated urban forms can improve ULUE under low carbon constrains. In addition, there are both positive and negative correlations between urban sprawl and ULUE in different regions. Today's choices on urban form can restrict the development pattern of cities and lock in pathways of carbon emissions in the future. Based on the findings in this study, the government should pursue optimal city sizes, avoid scattered patterns and aim for compact urban form.

Changes in agricultural land requirements for food provision in China 2003-2011: A comparison between urban and rural residents

Rapid income growth and urbanization have led to significant changes in food consumption patterns in China. The impact of dietary changes is likely to increase agricultural land demand for food provision. This study investigates the changes in three types of agricultural land requirements for urban and rural residents in China using embodied land use intensities. Our results indicate that total per capita cultivated land requirement of rural residents decreased by 24.3%, from 1984 to 1501 m² during the study period, while total per capita cultivated land requirement for urban residents decreased by 25.1%, from 2736 to 2049 m². Total per capita pasture land requirement of rural residents increased by 13.6%, from 543 to 617 m², while total per capita pasture land requirement of urban residents decreased by 31.4%, from 2991 to 2053 m². Total per capita forest land requirement of rural residents increased by 31.0%, from 45 to 59 m², while total per capita forest land requirement of urban residents decreased by 8.4%, from 164 to 150 m². Our study provides clear implications about the linkages between dietary change and agricultural land demand. Our results imply that without sufficient improvement in production efficiency, pressures posed by dietary change on land resources related to the provision of food will remain high in the future.

A new framework of land use efficiency for the coordination among food, economy and ecology in regional development

Great challenges regarding land use conflicts in rapid urbanization call for deeper research on land use efficiency (LUE) from the perspective of sustainable land use for the coordination among food security, economic development, and ecological protection. This study firstly develops a new framework of LUE based upon the expectations in land use and the coordination among three sub-categories in food production, economic development, and ecological protection, then, uses the coupling coordination degree model to quantify the spatial differentiation characteristics and coupling coordination relationships among three sub-categories, and finally uses the multivariable linear regression and geographical detectors to analyze the impact factors of sub-category efficiency. The framework is applied to Jiangsu Province in eastern China by using ten indicators (i.e., cultivated land quality, grain output, multiple cropping index, average GDP per km², population density, proportion of industry and service industry, vegetation cover index, water conservation index, soil retention index, and carbon sequestration index) in terms of food production, economy, and ecology analysis at the county level. Compared with expectations, the LUE of Jiangsu in food production, economic development, and ecological protection is 54.15%, 85.56%, and 54.95%, respectively, indicating that Jiangsu has great potential for sustainable land use. The coupling coordination degree in land use generally synchronizes with the coupling degree, accounting for 65.34% of the province's area, of which 75.00% are in lower-coupling & lower-coordination, medium-coupling & medium-coordination. Among all the factors, proportion of industry and service industry, population density, multiple cropping index, average GDP per km², and water conservation index have the most important roles in the coordinated development of land use sub-systems. Therefore, we suggest land use/urban management need to implement more integrated planning and differentiated strategies to stimulate land use potential and maintain efficient and sustainable land use.

Techno-economic assessment of coconut biodiesel as a potential alternative fuel for compression ignition engines

Over the past years, there were dramatic improvements in identifying and assessing various feedstocks for the production of biodiesel fuels. To promote a particular feedstock as a renewable source of energy, it is important to analyze their energy, economic, and engine performance characteristics. The current work attempts to evaluate the net energy and economic indices for both fossil diesel and coconut-blended diesel (B20) considering the diesel consumption by the Indian railways. Further, we present the experimental results of a multi-cylinder diesel engine operated with neat coconut biodiesel (B100) and fossil diesel at various load and speed conditions. The engine experiments reveal that the coconut biodiesel exhibits leaner combustion and shorter ignition delay than fossil diesel. Lower amount of carbon monoxide, hydrocarbon, and smoke emission is observed in the case of coconut biodiesel, with higher levels of nitric oxide (14%) and fuel consumption than diesel. The coefficient of variation in indicated mean effective pressure is within the range of better driveability zone for both the fuels at all test conditions. Overall the engine performance, emission and combustion results with neat coconut biodiesel are favorable with a penalty in NO emission at high load conditions. The techno-economical study highlights higher production cost per liter of B20 than the cost of fossil diesel. However, the net energy ratio (NER) for B20 is 1.021, favoring higher output than diesel and thus lowers the dependency on crude oil.

Vertical farming increases lettuce yield per unit area compared to conventional horizontal hydroponics

Vertical farming systems (VFS) have been proposed as an engineering solution to increase productivity per unit area of cultivated land by extending crop production into the vertical dimension. To test whether this approach presents a viable alternative to horizontal crop production systems, a VFS (where plants were grown in upright cylindrical columns) was compared against a conventional horizontal hydroponic system (HHS) using lettuce (Lactuca sativa L. cv. "Little Gem") as a model crop. Both systems had similar root zone volume and planting density. Half-strength Hoagland's solution was applied to plants grown in perlite in an indoor controlled environment room, with metal halide lamps providing artificial lighting. Light distribution (photosynthetic photon flux density, PPFD) and yield (shoot fresh weight) within each system were assessed. Although PPFD and shoot fresh weight decreased significantly in the VFS from top to base, the VFS produced more crop per unit of growing floor area when compared with the HHS. Our results clearly demonstrate that VFS presents an attractive alternative to horizontal hydroponic growth systems and suggest that further increases in yield could be achieved by incorporating artificial lighting in the VFS.