The study aimed to explore the yield traits and identify key factors for increased production in the cotton cultivar ‘Liaomian 21’. Based on the data of 2018 to 2021 regional tests, the high yield, stable yield and related agronomic characters of the variety were analyzed using principal component analysis and path analysis. The results showed that ‘Liaomian 21’ showed good high yield, stability and adaptability. Lint yield was significantly positively correlated with the number of bolls per plant, pre-frost flowering rate, single boll weight and lint percentage; 5 principal components were extracted from the principal component analysis, and their cumulative contribution rate was 87.94%; path analysis showed that the factors affected lint yield of ‘Liaomian 21’ were the number of bolls per plant (0.583), lint percentage (0.459), and single boll weight (0.369) in terms of contribution rate. Studies have shown that ‘Liaomian 21’ is a cotton variety with stable yield, strong adaptability and excellent quality. It has good salt resistance and is suitable for large-scale promotion and application in the Yellow River Basin, especially in saline-alkali land.

In order to investigate the response of yield and quality of spring maize to changes in moisture and heat, a sowing experiment was carried out in Xifeng, Gansu Province. The characteristics of growth, development, yield and quality of spring maize under different sowing dates were analyzed. The results showed that with the delay of sowing date, the length of development period of spring maize shortened, timely early sowing could make full use of climate resources to increase the process of material accumulation; leaf area index, dry matter accumulation and yield components changed greatly in different sowing dates, and were closely related to the matching degree of hydrothermal resources; the growth rate of dry matter weight had the characteristics of slow-fast-slow, the growth rate before seven-leaf stage was slow, accelerated from jointing to milk-ripening, and decreased after milk-ripening, there was a significant difference in dry matter quality between tasseling-milk ripe, milk ripe-mature; the effect of sowing date on essential amino acids, semi-essential amino acids, non-essential amino acids, protein, fat and crude fiber of spring maize was not obvious. The study found that meteorological factors have a direct impact on the quality of maize. According to the climate year type, the suitable sowing date of maize is selected, so that the grain filling period is under superior light and heat conditions, and the effects of frost and drought can be avoided. Maize can achieve high yield. The normal or more precipitation in March to early April in spring is suitable for early sowing, and the most suitable sowing period is April 20-25. The less precipitation in March to early April in spring is suitable for late sowing, and the most suitable sowing period is April 25-May 5. The study provides a reference for dryland maize in the northwest Loess Plateau to cope with climate change.

To solve the bottleneck problems of poor development and serious degradation of Hedysarum scoparium artificial shrubbery in the western Ordos region of Inner Mongolia, and to screen the optimal stubble height for promoting the growth of Hedysarum scoparium, the artificial shrubbery of Hedysarum scoparium in Etuoke Banner of western Ordos was taken as the research object. The 0 cm (H₁), 10 cm (H₂) and 20 cm (H₃) stubble treatments were carried out, and the non-stubble Hedysarum scoparium was used as the control (CK). The effects of different stubble treatments on the fine root chemical properties and soil nutrients of Hedysarum scoparium were analyzed. The results showed that: (1) the chemical traits of fine roots of Hedysarum scoparium showed that the 10 cm flat stubble treatment was superior to other flat stubble treatments, and the average values of fine root carbon content, fine root nitrogen content and fine root carbon-nitrogen ratio in the second year of flat stubble were 346.72, 4.91 and 70.57 g/kg, respectively. (2) Under different flat stubble treatments, the soil nutrients under Hedysarum scoparium forest were also different. The 10 cm flat stubble treatment was the best, and the soil organic matter, soil available nitrogen, soil available phosphorus and soil available potassium were 6.61, 6.11, 2.48 and 28.43g/kg, respectively. The soil nutrients gradually decreased with the increase of soil depth, and the 0-10 cm surface soil layer was the best. (3) The comprehensive analysis of membership function of each index in the second year of flat stubble showed that 10 cm flat stubble treatment was the best. The paper provided a theoretical basis and technical support for the scientific guidance of ecological protection and restoration actions in western Ordos and even similar desert environments.

Through the 2022 Hebei Province Farmland Quality Evaluation Project, data from farmland quality monitoring points in eight counties of the Ningjinbo-Daluze low plain area were summarized and analyzed to evaluate the quality of farmland and soil nutrient status in the region. Using the grid method to evenly arrange sample evaluation units, the five-point method was adopted to collect cultivated soil samples from the surface layer (0-20 cm), and laboratory tests were conducted according to the soil testing series standards. Referring to the National Farmland Quality Grade Evaluation Index System of the Ministry of Agriculture and Rural Affairs, the weight of the indicators was determined. For numerical indicators of organic matter, total nitrogen, available phosphorus, and available potassium, the membership degree was determined by establishing functional relationships. For other conceptual indicators, the Delphi method expert scoring was used to give the membership degree, and the cumulative method was used to calculate the comprehensive index of arable land quality to obtain the arable land quality grade. The results showed that the average quality grade of cultivated land in the area was 3.51, with the main cultivated land grades being third and fourth grade. The third grade cultivated land was the main body, with an area of 140191 hm², accounting for 49.44% of the total cultivated land area in the area. The overall level of nutrients in the cultivated land in this area was relatively high, all of which were above level three. Nutrients were evenly distributed within the region, and the maximum values of organic matter, total nitrogen, available phosphorus, and available potassium appeared around the ancient Daluze marsh land. By analyzing the factors affecting the quality evaluation of cultivated land, such as irrigation guarantee, the texture and configuration of the plow layer, and the reserve of organic matter content, measures and suggestions for maintaining the quality level of cultivated land in the region were proposed, providing reference for soil nutrient monitoring, improving cultivated land quality, protecting ecological balance, and maintaining sustainable agricultural development in other low plain areas in Hebei Province.

The data of farmland ecosystem in Wuwei City from 2010 to 2022 were collated and calculated, and the total amount of carbon source / sink and its influencing factors were analyzed, so as to provide a basis for promoting the low-carbon, high-yield and sustainable development of agriculture in Wuwei City. Firstly, the agricultural ecosystem carbon source/sink formula was used to calculate the total agricultural carbon emissions and carbon absorption. Secondly, the LMDI model was applied to decompose the driving factors of agricultural carbon sources/sinks in Wuwei City. The results showed that compared with 2010, total agricultural carbon emissions in Wuwei City decreased by 14.42% in 2022, showing a downward trend, and total carbon sequestration increased by 31.66%, showing an upward trend. The structure of various carbon sources was: fertilizer (33.25%) > agricultural film (29.88%) > tillage (22.78%) > irrigation (14.91%) > machinery (0.19%), fertilizer had the fastest rate of decline; the structure of various carbon sinks was: maize (52.67%) > wheat (19.37%) > vegetables (13.87%) > oilseeds (9.17%) > legumes (1.76%) > potatoes (1.64%) > melons (1.52%). From the perspective of influencing factors, economic factors played a promoting role in carbon emissions, while carbon sink coefficient, carbon sink structure, and carbon sink technology played a promoting role in carbon absorption. By calculating the total amount of carbon sources/sinks in Wuwei City from 2010 to 2022 and analyzing the influencing factors, it was shown that reasonable control of agricultural production inputs and optimization of industrial structure could effectively reduce agricultural carbon emissions.

The aims are to explore the main influencing factors of remote sensing ecological index (RSEI) in Maqu County and find out the relationship between different land use types and ecological quality changes, to provide basic data for ecological protection and sustainable development in the Yellow River Basin. Based on remote sensing data, this paper analyzed the change characteristics of vegetation coverage and RSEI in Maqu County from 2000 to 2021. The results showed that: (1) the land use in Maqu County was mainly grassland, and the change of land types was not large from 2000 to 2021. The ecological environment quality showed a significant decline trend in 2011 and 2017, and the environmental quality increased significantly in 2021. (2) The area of ecological degradation in Maqu County from 2000 to 2010 was 4484.72 km², and the area of ecological improvement from 2011 to 2021 was 8374.59 km², with an increase of nearly 70.05%, and the area of ecological quality improvement increased significantly. (3) From 2000 to 2021, the transfer of land use types in Maqu County was mainly between forest land and grassland. The ecological environment quality of Maqu County was closely related to vegetation cover, humidity and altitude had little influence on the ecological environment quality, but the influence of temperature had increased.

To clarify the impact of novel urea on yield and the efficiency of nitrogen fertilizer in summer maize, and to provide theoretical basis and technical support for its large-scale promotion and application, treatments were set as followed: no nitrogen fertilizer application (T₁), local farmers’ habitual fertilization (T₂, N 216 kg/hm²), conventional optimized fertilization (T₃, N 210 kg/hm²), controlled release urea and humic acid urea in a 1:1 ratio (T₄, N 210 kg/hm²), controlled release urea and humic acid urea in a 1:1 ratio with a 10% reduction of N for each (T₅, N 168 kg/hm²), controlled release urea (T₆, N 210 kg/hm²), and controlled release urea with a 20% reduction of nitrogen (T₇, N 168 kg/hm²). The effects of different fertilization treatments on yield, nitrogen absorption and utilization, and soil available nitrogen of summer maize were studied. The results showed that the yield of summer maize from T₃ to T₇ increased by 13.89% to 18.04% compared to T₁, with T₅ showing the largest increase. Compared with T₁ and T₂, T₃ to T₇ all increased the aboveground nitrogen accumulation and soil available nitrogen content during the mature stage of summer maize, and T₅ showed significant differences in aboveground nitrogen accumulation compared to T₁ and T₂ (P<0.05). In addition, the nitrogen fertilizer utilization rate of T₅ was as high as 60.22%, and the nitrogen fertilizer partial productivity was 74.56 kg/kg. In conclusion, optimizing nitrogen application can promote the increase of summer maize yield. Under the experimental conditions, the 1:1 combination of controlled release urea and humic acid urea with a 10% reduction of nitrogen for each can be promoted and applied in the high-yield area of summer maize in northern Henan Province.

To explain the effect of Zenia insignis litter on soil fertility and its mechanism, the relationship between soil fertility and physicochemical properties of different plant litter and soil were studied through the relative determination and correlation analysis. From August 2022 to September 2023, the main distribution points of Zenia insignis plantation were selected as the investigation and research plots in Yizhou District and surrounding counties and districts of Hechi City, Guangxi. The results showed that: (1) from the perspective of basic soil physical and chemical characteristics, the soil fertility of Pteroceltis tatarinowii and Zenia insignis plots was better than that of Cinnamomum burmanni. (2) From the perspective of decomposition rate of litter, the order of decomposition rate of different plant litter was Pteroceltis tatarinowii > Zenia insignis > Cinnamomum burmanni. (3) The organic matter content in litter had a significant positive correlation with the total phosphorus and available phosphorus content in soil, and a highly significant negative correlation with the C/P in soil. The total phosphorus content and C/P in litter were significantly positively correlated and negatively correlated with C/N in soil, respectively. There was a significant negative correlation between C/N in litter and C/P in soil. The N/P of litter was significantly positively correlated with the total nitrogen and alkaline nitrogen content in the soil, while the other measured indexes of litter were not significantly correlated with the physical and chemical indexes of soil. From this, it could be seen that the physical and chemical characteristics of litter had an important impact on soil fertility changes. Planting Zenia insignis could improve the fertility level of soil in karst areas to a certain extent through the litter. The research aims to provide theoretical support for vegetation restoration in karst areas and the protection of rare wild plants unique to China, as well as to prevent the deterioration of the ecological environment.

Heavy metal contamination of soil affects soil and crop quality and poses a threat to human health. Traditional phytoremediation techniques face challenges such as prolonged remediation cycles, poor adaptability, and the complexity of pollution, thus making it crucial to explore the mechanisms of removal, decomposition, and detoxification through enhanced phytoremediation technologies in heavy metal-contaminated soils. By collecting literature on intensive phytoremediation of heavy metal-contaminated soils, we concisely described techniques such as genetic engineering, the application of plant growth regulators, microbial synergistic remediation, and the addition of chelating agents, focusing on how these techniques enhance plant tolerance to heavy metal ions and affect their transport within the plant. This paper proposed that future agricultural production should focus more on understanding the molecular mechanisms and gene regulatory networks of plants, as well as the demand and uptake capacity of different plants for specific nutrients. Additionally, it suggested exploring more in situ bioresistance resources and combinatorial modes, enriching the symbiotic systems of bacteria and plants within contamination ranges, optimizing the dosage of chelating agents, and prioritizing biodegradable chelating agents or developing environmentally friendly substitutes. These efforts aimed to provide a theoretical and practical basis for utilizing enhanced phytoremediation technologies to address soil heavy metal contamination.

To explore the effect of nitrogen application on yield and thousand-grain weight of flax, and provide a reference for flax nitrogen application management, a meta-analysis was conducted using 116 pieces of data from 21 papers collected up to 2023. The data were grouped according to the test year, test location, soil type, soil organic matter content, soil alkali hydrolyzed N content, soil available P content, soil available K content and soil pH value. The comprehensive effect of nitrogen application on flax yield and thousand-grain weight was explored, with no nitrogen fertilizer application serving as the control group. The research results indicated that when the nitrogen application was between 120-150 kg/hm², the effect values on flax yield (22.14%) and thousand-grain weight (4.55%) were the highest; the effect value of nitrogen application on flax yield (20.44%) was the highest from 2010 to 2013; the effect values of nitrogen application on Gansu flax yield (23.17%) and thousand-grain weight (5.23%) were the highest; the effect values of nitrogen application on flax yield (23.30%) and thousand-grain weight (5.63%) were the highest in sandy loam soil. When soil alkali hydrolyzed N content was >50 mg/kg, soil organic matter content was <10 g/kg, soil available P content was >25 mg/kg, soil available K content was 100-200 mg/kg, and soil pH value was 8-8.5, the nitrogen application of flax had the highest yield-increasing effect, which were 19.42%, 20.22%, 21.38%, 20.10% and 20.22%, respectively. When soil alkali hydrolyzed N content was <50 mg/kg, soil organic matter content was <10 g/kg, soil available P content was 15-25 mg/kg, soil available K content was 100-200 mg/kg, and soil pH value was 8-8.5, the nitrogen application had the highest effect on improving the thousand-grain weight of flax, which was 5.77%, 6.33%, 7.60%, 5.31% and 4.73%, respectively. When the nitrogen application rate was between 120-150 kg/hm², the increases in flax yield and thousand-grain weight were the highest. The research results of this experiment could provide a reference for increasing yield and thousand-grain weight of flax under different production conditions in the future.

The paper aims to investigate the effects of bumblebee pollination on the quality and economic benefits of fresh tomatoes. This study took the fresh tomato variety ‘Jingcai 8’ as the research object. Through relevant investigations, data analysis, and economic benefit calculations, the effects of bumblebee pollination and hormone dipping on fresh tomatoes overwintering cultivated in greenhouse were studied. The research results showed that bee pollination increased the fruit setting rate, single fruit weight, and total yield of fresh tomatoes. The rate of malformed fruits decreased by 78.05%, the number of single fruits increased by 91.52%, the total sugar content increased by 17.44%, the soluble solids increased by 7.89%, the sugar acid ratio increased by 14.07%, tomato sales revenue increased by 8.06%, cost savings were 11550 yuan/hm², efficiency increased by 38910 yuan/hm², and total benefits increased by 12.49%. In addition to economic benefits, bee pollination reduced the use of hormones and pesticides, which had good ecological benefits. This study provides a reference for the promotion and application of bee pollination technology in the production of fresh tomatoes.

In this study, data on yield and quality of Zhaotong apples were obtained from China National Knowledge Internet (CNKI) full text database and Web of Science database (WOS), a linear model was established by fitting a regression model using least squares estimation in order to study the effects of climatic factors on yield and quality of Zhaotong apples. The coefficient of determination of annual rainfall was low for yield and soluble solids content, and was high for titratable acid and water contents. Mean annual temperature had lower coefficients of determination for single fruit weight, titratable acid content and fruit shape index, and had higher coefficients of determination for yield and soluble sugar content. In the Zhaotong apple growing area, the increase of annual rainfall and mean temperature decreased apple quality, while the increase of mean annual maximum temperature increased apple yield, and the increase of mean annual minimum temperature increased single fruit weight. Taking into account the current climatic factors and future trends, it is recommended to plant varieties tolerant to high temperatures and to irrigate 2-3 times from autumn to spring. In breeding and production management, it is recommended to focus on the selection of varieties with extended cold periods and late flowering and working out production programs.

In order to gain a deeper understanding of the research status and future directions in the field of leisure agriculture, this paper took the relevant literature published in the CSSCI journals and Peking University core journals collected by CNKI from 2012 to 2023 as the data sources, and used CiteSpace software to analyze the dynamic trends of collaborating authors, collaborating institutions, research trends, and publication volume in this field. The results indicate that the majority of authors have rich connections among themselves, but some teams still have limited network connections. The research institutions are still mainly universities, and their connections withindustries are not close enough. The research topics focus on "rural tourism", "models", "industrial upgrading", etc., mainly focusing on 12 themes including leisure agriculture strategies, rural tourism, influencing factors, development difficulties, industrial integration, low-carbon transformation, and key areas. The related research shows the development trend from macro to micro, and from single discipline extension to interdisciplinary intersection. Future research can delve deeper into the diversity of research teams, the expansion of research content, and the innovation of research contexts. The conclusions can provide theoretical basis and practical guidance for comprehensively promoting rural revitalization.