Search Results (14)

To investigate the effects of planting density and chemical regulation measures, as well as their interactions, on the plant morphological characteristics, stem mechanical properties, leaf anatomical structure, dry matter accumulation and allocation, and yield and its components of grain maize in the Hexi Oasis irrigation area, a field experiment was conducted from 2024 to 2025. Planting density was set as the main factor, with five density levels: 82,500 plants·ha⁻¹ (M1), 97,500 plants·ha⁻¹ (M2), 112,500 plants·ha⁻¹ (M3), 127,500 plants·ha⁻¹ (M4) and 142,500 plants·ha⁻¹ (M5). Chemical regulation measures were set as the secondary factor, consisting of two treatments: spraying 30% aminoethyl hexanoate·ethephon at the 10-leaf stage (T1) and spraying an equal amount of water as the control (T2). The results revealed that, as planting density increases, the maize plant height, ear height and stem breakage rate rise continuously, whilst stem diameter, stem breaking resistance, rind puncture strength, leaf thickness and epidermal tissue thickness showed a downward trend. The leaf area index, ear length, kernel number per ear, kernel weight and yield all exhibited a trend of first increasing and then decreasing, reaching their peak at the M3 planting density. Compared with conventional planting patterns, spraying chemical regulators significantly reduced plant height by 10.66~13.99% and ear height by 16.12~19.57%, increased stem diameter by 2.12~13.79%, and enhanced stem breaking resistance by 7.71~23.11% and rind puncture strength by 5.17~12.65% at 30 days after silking. Additionally, it delayed leaf senescence, increased the leaf area index by 4.37~10.03% during the filling stage, and increased yield by 1.99~4.06%. The synergistic effect of moderately increasing planting density combined with chemical regulation can effectively coordinate the ‘population–individual’ contradiction in maize, reduce plant height and ear height and increase stem diameter and rind puncture strength, while maintaining a higher leaf area index after the silking stage and promoting dry matter translocation to grains, thereby achieving a synergy between lodging resistance and high yield. Among them, a planting density of 112,500 plants·ha⁻¹ combined with spraying chemical regulators yielded the highest maize yield and harvest index, reaching 20.28~20.48 t·ha⁻¹ and 0.52~0.53, respectively. Compared with other treatments, the increases ranged from 2.54~47.51% for yield and from 1.92~36.84% for the harvest index. Meanwhile, this treatment exhibited superior stem mechanical properties and a lower stem breakage rate. Taking into account factors such as lodging resistance, yield, dry matter accumulation and allocation, it has been determined that a planting density of 112,500 plants·ha⁻¹ combined with spraying 30% aminoethyl hexanoate·ethephon at the 10-leaf stage is an effective strategy for achieving both lodging resistance and high yield in grain maize in the Hexi Oasis irrigation area. Full article

Excessive nitrogen addition in farmland on the Loess Plateau reduces soil quality and endangers the atmospheric environment. We designed an experiment to investigate the effects of different nitrogen application rates on the soil physicochemical properties and microbial diversity of spring wheat fields on the Loess Plateau, aiming to identify the optimal nitrogen application rate and avoid the detrimental effects of excessive nitrogen addition. A field experiment was conducted from 2022 to 2023 with four nitrogen (N) application rates (0, 55, 110, and 220 kg·N·ha⁻¹·y⁻¹). This study aimed to assess the changes in soil properties, nutrient contents, enzyme activities, and bacterial community structure. The results showed that increasing N application generally enhanced soil bulk density, nitrate nitrogen (NO₃⁻-N), ammonium nitrogen (NH₄⁺-N), and microbial biomass nitrogen (MBN) (p < 0.05). In contrast, soil water content initially increased and then decreased. Soil organic carbon and total nitrogen rose markedly with higher N inputs, particularly in the 0–20 cm layer, whereas total phosphorus was less affected. Nitrogen addition stimulated soil enzyme activities (protease, urease, nitrate reductase, and nitrite reductase), though excessive input (220 kg·N·ha⁻¹·y⁻¹) produced inhibitory effects. Actinobacteria (relative abundance: 29–35%) and Proteobacteria (relative abundance: 14–22%) were the dominant phyla in all treatments. Alpha diversity peaked at low nitrogen input (55 kg·N·ha⁻¹·y⁻¹), while high N level reduced evenness and species richness (p < 0.05). Principle Coordinate Analysis (PCoA) revealed that both N application and soil depth shaped microbial community assembly, with deeper layers (20–40 cm) being more sensitive to N input. Correlation analysis indicated that soil moisture, bulk density, and C:N:P stoichiometry were key drivers of bacterial community variation. Overall, moderate nitrogen input (110 kg·N·ha⁻¹·y⁻¹) improved soil fertility and supported microbial functionality, whereas excessive application degraded soil structure and reduced biodiversity. These findings highlight the need for balanced N management strategies in rain-fed agriculture of the Loess Plateau to sustain both productivity and ecological stability. Full article

Conducting research on the evaluation of rural resilience and risk governance strategies in the middle reaches of the Heihe River can provide a scientific basis for the sustainable development of rural areas in the inland river basins of arid regions. Affected by water resource constraints, the expansion of artificial oases, and excessive exploitation of groundwater, the rural areas in the middle reaches of the Heihe River Basin, the second largest inland river in the arid region of northwest China, are confronted with prominent contradictions in the human-land relationship and urgently need to enhance their ability to cope with risks. Based on the remote sensing data of land use and major socio-economic data, this study draws on the theory of landscape ecology to construct a disturbance-resistance-adaptability evaluation system. Taking Ganzhou District, a typical irrigated agricultural area, as a case study, the study uses the entropy weight method, resilience change rate, and obstacle degree model to analyze the rural resilience level and its changing characteristics from 1990 to 2020, identifies the key obstacle factors affecting the development of rural resilience, and proposes risk governance strategies accordingly. Main conclusions: (1) The overall rural resilience index is relatively low, showing significant spatial disparities. Towns with well-developed multifunctional agriculture, nature reserves, and ecological-cultural control lines have higher resilience indices. (2) The change rate of the rural resilience index demonstrates phase heterogeneity, generally undergoing a “relative stability-increase-decrease” process, and forming a differentiation pattern of “decrease in the north and increase in the south”. (3) Internal risks to rural resilience development in the Ganzhou District mainly stem from low economic efficiency, fragile ecological environment, and unstable landscape patterns, among which efficiency-dominant and landscape-stability obstacle factors have a broader impact scope, while habitat resistance-type obstacle factors are mainly concentrated in the western part and suburban areas. Enhancing the benefits of water and soil resource utilization, strengthening habitat resistance, and stabilizing landscape patterns are key strategies for current-stage rural resilience governance in the middle reaches of the Heihe River. This study aims to optimize the human-land relationship in the rural areas of the middle reaches of the Heihe River. Full article

Plant species diversity and spatial distribution patterns are critical for understanding ecosystem dynamics in arid and fragile environments. This study investigates the diversity, spatial distribution, and interspecific associations of shrubs and herbaceous plants in the transition zone of the desert oasis located in the Hexi Corridor and southern edge of the Badanjilin Desert, China. Vegetation data were collected across sample plots spanning three counties in Zhangye City. Important values, diversity indices, and spatial distribution metrics were calculated to evaluate plant species dominance and community structure. Interspecific relationships were analyzed using variance ratio (VR), clumping indicators, and corrected χ² tests. The shrub community exhibited low species diversity (H′ = 1.754) and was dominated by Reaumuria songarica (Pall.) Maxim (IV = 111.175), reflecting its superior adaptability to arid conditions. In contrast, the herbaceous community displayed higher diversity (H′ = 2.498), with Aristida adscensionis L. (IV = 48.6174) as the dominant species. Both communities showed predominantly aggregative spatial distribution patterns, influenced by localized resource availability and adaptive strategies. Weak interspecific associations characterized the shrub community, with limited competition among dominant species, while the herbaceous community demonstrated significant negative correlations, indicating stronger resource competition. The study highlights the contrasting diversity and ecological roles of shrubs and herbaceous plants in arid ecosystems, shaped by resource limitations and environmental stressors. Effective conservation strategies are needed to protect dominant species and sustain ecosystem resilience in desert regions. Future research should focus on below-ground interactions and long-term monitoring to enhance understanding of species coexistence and community stability. Full article

Northeast China (NEC) is a major spring maize (Zea mays L.) growing belt, and the outputs substantially influence national grain production. However, the maize grain yield per unit area has little changes in recent years, partially due to the lack of elite germplasm resources and innovation. Therefore, this study aimed to determine the performance of diverse populations in NEC to propose appropriate strategies for the utilization of elite germplasm to broaden the genetic base of Chinese germplasm. Fifteen diverse maize populations from the International Maize and Wheat Improvement Center (CIMMYT) and the U.S. were crossed to two local tester lines, representing Chinese heterotic groups Reid and Lancaster, for evaluating the combining ability and heterosis in three locations (Gongzhuling, Jilin Province, and Harbin and Suihua, Heilongjiang Province) in NEC over two years. The U.S. (BS13(S)C7 and BS31) and Chinese (Ji Syn A) populations exhibited more favorable alleles for high yield potential in all locations tested. Furthermore, the PH6WC × BS31 and PH6WC × Ji Syn A crosses had higher grain yields, and an appropriate number of days to silking, ear height, and resistance to lodging at Gongzhuling and Harbin in NEC. The best strategies for utilizing these diverse germplasms may be to develop new inbred lines from the existing elite populations or improve the grain yield and resistance to lodging of the elite line PH4CV for broadening the genetic base of the Chinese group Lancaster in NEC. Full article

Water and nitrogen are the primary constraints on improving agricultural productivity. The aims of this study are to investigate the synergistic effects of water and nitrogen, optimize their combination schemes under mulched drip irrigation systems in the northwest region of China, and offer scientific insight into enhancing water and nitrogen use efficiency in potato cultivation. The traditional cultivar “Qing Shu 10” was chosen for the test material. A two-year field study on potato water–nitrogen interaction was conducted in the central Hexi Corridor, within Ganzhou District of Zhangye City, with three irrigation levels (W1 (336 mm), W2 (408 mm), and W3 (480 mm)) and three nitrogen application rates (N1 (44 kg ha⁻¹), N2 (192 kg ha⁻¹), and N3 (240 kg ha⁻¹)) using a fully randomized combination design, resulting in nine treatments. This study examined the varying responses in potato yield and water–nitrogen use efficiency to different water–nitrogen combinations in the Hexi Corridor region, developed a mathematical regression model to predict the economic benefit of potatoes based on water–nitrogen interactions, and refined the application strategy. The results indicated that both the volume of irrigation water and the rate of nitrogen application significantly influenced potato yield and water–nitrogen utilization efficiency. A distinct interactive effect was observed between irrigation volume and nitrogen application rate. The reduced irrigation volume restricted nitrogen uptake, with an average increase of 31.87% in nitrogen fertilizer partial productivity and 31.54% in potato yield when moving from W1 to W2 over two years and only a 6.02% and 5.48% increase from W2 to W3, respectively. Similarly, reduced nitrogen application rates also hindered water uptake by potatoes, with increases of 9.05% in water use efficiency, 12.14% in irrigation water use efficiency, 12.12% in yield from N1 to N2, and only 1.98% and 1.69% increases in irrigation water use efficiency and yield from N2 to N3, while water use efficiency decreased by 1.17%. The highest yield values over the two-year period were observed in the N2W3 treatment, with 43,493.54 and 43,082.19 kg ha⁻¹. The irrigation volume, nitrogen application rate, and potato economic benefit were well modeled by a quadratic regression, with an R² of 0.996 for both predicted and actual economic benefit over two years, indicating a trend of initial increase followed by a decrease as water and nitrogen levels increased. Through simulation optimization and a thorough analysis of multiple indicators, the N2W3 treatment yielded an economic benefit exceeding 25,391.13 CNY ha⁻¹ and demonstrated a high water–nitrogen utilization efficiency. This treatment not only enhances potato economic benefit but also minimizes agricultural resource inputs, establishing it as the optimal water and fertilizer management strategy for this study. Full article

The land surface albedo (LSA) represents the ability of the land surface to reflect solar radiation. It is one of the driving factors in the energy balance of land surface radiation and in land–air interactions. In this paper, we estimated the land surface albedo based on GF-1 WFV satellite data that have a high spatial and temporal resolution and cross-validated the albedo estimation results. The albedo estimations and validations were performed in the Ganzhou District, Zhangye City, China, and the Sindh Province, Pakistan. We used the direct estimation method which used a radiative transfer simulation to establish the relationship between the narrow band top of the atmosphere bidirectional reflectance and the land broadband albedo to estimate the albedo data. The results were validated with ground data, Landsat data, MODIS products, and GLASS products. The results show that the method can produce highly accurate albedo estimation results on different land cover types (RMSE: 0.026, R²: 0.835) and has a good consistency with the existing albedo products. This study makes a significant contribution to improving the utilization of GF data and contributes to the understanding of land–air interactions. Full article

Controlling environmental pollutant discharge and water resource demand is crucial for the sustainable development of agriculture and rural areas in arid oases. Taking Ganzhou, an arid oasis in Northwest China, as an example, we established an analysis framework for the relationship between the planting industry transformation and the resource and environmental pressures, from 2011 to 2020, through the methods of inventory, coefficient and quota accounting. The results showed that the planting scale of crops in oases has continuously expanded, with a structural dominance of corn seed production. Pollutant discharge showed a “Z”-type evolution trend, and the demand for water consumption continued to increase. The transformation of the planting industry and pollutant discharge showed coupled trade-offs and a synergetic alternating fluctuations coupling relationship, which was highly co-evolutionary with the demand for water resources. Crop planting exhibited four spatial patterns, namely the mixed planting area of grain and cash crops grown in mountain areas (GCPA), suburban scale vegetable planting (SVPA), planting of seed production corn (MSPA), and the compound planting area of grain crops, oil crops, vegetables, and other characteristic crops (CMPA). MSPA and SVPA had the highest total and average volume per unit area, respectively. The planting industry transformation and evolution of resource and environment pressures are closely related to changes in national strategies, regional agricultural policies, and environmental regulations. Therefore, studying their relationships provides a scientific basis for the formulation of suitable countermeasures, according to the development stage of a region. Full article

Improving production efficiency can help overcome the constraints of resource scarcity and fragile environments in oasis agriculture. However, there are few studies about the effect of farmers’ cognition of resources and the environment on their production efficiency. Taking farmers in the Ganzhou District of Zhangye—a typical representative of oasis agriculture in an inland river basin in Northwest China—this study empirically analyzed the effect of farmers’ cognition of resources and the environment on agricultural production efficiency. The average agricultural productivity of the surveyed farmers is 0.64, which is much lower than the average level in China. Farmers’ cognition of resources and the environment is related to green production willingness and behavior. Green production willingness, green production behavior between cognition of resources and the environment, and agricultural production efficiency play a chain mediating role, showing that farmers’ cognition of resources and the environment indirectly affects production efficiency. Green planting willingness is formed based on cognition of resources and the environment; when farmers translate willingness into behavior, it will further improve agricultural production efficiency. Recommendations are made based on the findings, such as strengthening the cognition of resources and the environment, mobilizing enthusiasm for green production, and promoting the practice of green planting. Full article

Land surface albedo (LSA) is an important parameter that affects surface–air interactions and controls the surface radiation energy budget. The spatial and temporal variation characteristics of LSA reflect land surface changes and further influence the local climate. Ganzhou District, which belongs to the middle of the Hexi Corridor, is a typical irrigated agricultural and desert area in Northwest China. The study of the interaction of LSA and the land surface is of great significance for understanding the land surface energy budget and for ground measurements. In this study, high spatial and temporal resolution GF-1 wide field view (WFV) data were used to explore the spatial and temporal variation characteristics of LSA in Ganzhou District. First, the surface albedo of Ganzhou District was estimated by the GF-1 WFV. Then, the estimated results were verified by the surface measured data, and the temporal and spatial variation characteristics of surface albedo from 2014 to 2018 were analyzed. The interaction between albedo and precipitation or temperature was analyzed based on precipitation and temperature data. The results show that the estimation of surface albedo based on GF-1 WFV data was of high accuracy, which can meet the accuracy requirements of spatial and temporal variation characteristic analysis of albedo. There are obvious geographic differences in the spatial distribution of surface albedo in Ganzhou, with the overall distribution characteristics being high in the north and low in the middle. The interannual variation in annual average surface albedo in Ganzhou shows a trend of slow fluctuations and gradual increases. The variation in annual albedo is characterized by “double peaks and a single valley”, with the peaks occurring from December to February at the end and beginning of the year, and the valley occurring from June to August. Surface albedo was negatively correlated with precipitation and temperature in most areas of Ganzhou. Full article

Paleoclimate research, which involves the study of climate and environmental changes in historical and geological periods, is typically conducted using high-resolution paleoclimatic proxies, such as tree rings, historical documentations, stalagmite, and ice core. Although each paleoclimate proxy has its own merits in paleoclimatic research, reconstructions based on a single proxy may suffer from shortcomings, including insufficient reliability and low coverage of the representative area. It may be possible to overcome these shortcomings by combining multi-paleoclimatic proxies to understand paleoclimatic changes. In this study, we attempt to combine tree-ring stable oxygen isotope ratio (δ¹⁸O), tree-ring width, and stalagmite thickness data as well as historical records to establish a 320-year (1675–1994) time series using principal component analysis in the water-scarce North China Plain (NCP). The results show that the first principal component (PC1) series is closely related to regional precipitation and the maximum temperature in summer. The spatial correlation pattern indicates that the PC1 series can represent the regional hydroclimate variation not only in the NCP but also in all of northern China. The significant (p < 0.001) correlations between the PC1 series and several East Asian summer monsoon (EASM) indices prove that the PC1 reflects the intensity of the EASM. The PC1 series is consistent with the interannual variations of two reconstructed solar activity correlation indexes (r = 0.48 and 0.46, n = 320, and p < 0.001). The results indicate that the hydroclimate variation in the NCP is affected by large-scale atmospheric circulations, such as EASM and solar activity, and shows the potential of combining multiple paleoclimate proxies for analyzing regional climate change. Full article

Although cambial reactivation is considered to be strongly dependent on temperature, the importance of water availability at the onset of xylogenesis in semi-arid regions still lacks sufficient evidences. In order to explore how environmental factors influence the initiation of cambial activity and wood formation, we monitored weekly cambial phenology in Qilian juniper (Juniperus przewalskii) from a semi-arid high-elevation region of northwestern China. We collected microcores from 12 trees at two elevations during the growing seasons in 2013 and 2014, testing the hypothesis that rainfall limits cambial reactivation in spring. Cambium was reactivated from late April to mid-May, and completed cell division from late July to early August, lasting 70–100 days. Both sites suffered from severe drought from January to April 2013, receiving < 1 mm of rain in April. In contrast, rainfall from January to April 2014 was 5–6 times higher than that in 2013. However, cambial reactivation in 2014 was delayed by 10 days. In spring, soil moisture gradually increased with warming temperatures, reaching 0.15 m³/m³ before the onset of xylogenesis, which may have ensured water availability for tree growth during the rainless period. We were unable to confirm the hypothesis that rainfall is a limiting factor of cambial reactivation. Our results highlight the importance of soil moisture in semi-arid regions, which better describe the environmental conditions that are favorable for cambial reactivation in water-limited ecosystems. Full article

Performance evaluation and influence factors analysis are vital to the sustainable water resources management (SWRM) in irrigation areas. Based on the objectives and the implementation framework of modern integrated water resources management (IWRM), this research systematically developed an index system of the performances and their influence factors ones of the SWRM in irrigation areas. Using the method of multivariate regression combined with correlation analysis, this study estimated quantitatively the effect of multiple factors on the water resources management performances of irrigation areas in the Ganzhou District of Zhangye, Gansu, China. The results are presented below. The overall performance is mainly affected by management enabling environment and management institution with the regression coefficients of 0.0117 and 0.0235, respectively. The performance of ecological sustainability is mainly influenced by local economic development level and enable environment with the regression coefficients of 0.08642 and −0.0118, respectively. The performance of water use equity is mainly influenced by information publicity, administrators’ education level and ordinary water users’ participation level with the correlation coefficients of 0.637, 0.553 and 0.433, respectively. The performance of water use economic efficiency is mainly influenced by the management institutions and instruments with the regression coefficients of −0.07844 and 0.01808, respectively. In order to improve the overall performance of SWRM in irrigation areas, it is necessary to strengthen the public participation, improve the manager’ ability and provide sufficient financial support on management organization. Full article

The Heihe River is the second largest river in arid areas of China, and the irrigation water of oasis agriculture in its middle reaches accounts for almost 80% of the water resources in the whole watershed. Corn is the most important crop in the middle reaches of the Heihe River, and its water consumption is about 50% of the total agriculture water consumption of the middle reaches. Therefore, in order to effectively use the water resources in the watershed, it is crucial to improve the efficiency of corn irrigation. In this paper, using the Ganzhou District in the middle reaches of the Heihe River as the study region, we carried out a field survey to obtain characteristics of seed and field corn. Based on our results, we conducted parameter calibration using the CROPWAT model and calculated the irrigation water requirements (IWR) of these two corn types. The irrigation water requirements of seed and field corn in the growing seasons were 470.1 and 488.5 mm, respectively. However, we observed big differences in the water consumption sequences of these two corn types. Prior to mid-July, evapotranspiration and IWR of seed corn were 14.3% and 20.1% higher, respectively, than those of field corn. In September, IWR of the two corn types started to decrease, with a value of 82.3 mm for seed corn, which was 32.1% lower than the IWR of field corn (108.7 mm) during the same period. However, there were no significant differences in the irrigation time and single irrigation amount for seed and field corn in the study area. Since corn is widely cultivated in the Zhangye Region, there is a considerable water-saving potential in agriculture if the irrigation water consumption can be adjusted according to the IWR of the two corn types. Full article