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Black-grass (Alopecurus myosuroides Huds.) is a common weed in Chinese wheat fields, and has become troublesome due to its evolution of herbicide resistance. One black-grass population (HN-14) collected from a wheat field where herbicides were applied was suspected to be resistant (R) to mesosulfuron-methyl. This study aims to establish a cross-resistance pattern and explore potential resistance mechanisms. The results of a whole-plant dose response assay showed that the resistant (R) population had a high of resistance to mesosulfuron-methyl (33-fold); meanwhile, no synergism of P450s activity inhibitor malathion was observed. The sequencing results revealed that ALS resistance mutation Trp-574-Leu occurred in R plants. The results of in vitro ALS enzyme activity assays also supported that the extractable ALS from R plants were 23.22-fold resistant to mesosulfuron-methyl. In the light of the "R" resistance rating system, HN-14 has evolved RRR and RR resistance to fenoxaprop-P-ethyl, clodinafop-propargyl, haloxyfop-methyl, and fluazifop-P-butyl and R? (resistance may be developing) to pinoxaden, however remains sensitive to imazethapyr, quizalofop-P-ethyl, tralkoxydim, and isoproturon. These results indicated that the mesosulfuron-methyl resistance in the black-grass population HN-14 was driven by a target-site mechanism rather than a nontarget (at least P450s-mediated) mechanism. [ABSTRACT FROM AUTHOR]

The impact of climate change on the crop water footprint (WF) is highly uncertain, hindering effective agricultural water use in response to climate change. This study proposes a factor sensitivity analysis method, which can screen out statistically significant climatic factors and interactions on crop WF under various uncertainties and determine water resource management measures to mitigate drought for different crops. A special case study was conducted in Heilongjiang Province, China. The results showed that (1) the annual change in crop WF showed a downward trend from 1988 to 2018. The crop WF was dominated by green water footprint (WF green), and the average occupancy rate of WF green in crops was 58.7%–74.1 %; the spatial distribution of WF has latitude zonality. (2) Drought has different effects on WF of different crops, and WF of soybean is susceptible to drought. Wind speed, sunshine hours, and humidity have a greater impact on crop WF in most growth stages. (3) The effect of climatic factors on crop WF varies in different months. The rice WF is mainly affected by the climate in May, and there is an interaction between May humidity and May rain. The WF of maize and soybeans are affected primarily by the climate in July, especially sunshine hours. The proposed approach attempts to analyze that crop WF is affected by not only an individual climatic factor but also their interactions. Crop water management practices should be adjusted based on the results to mitigate the adverse impact of climatic conditions on crop WF during different growing months. [ABSTRACT FROM AUTHOR]

• ESDA was applied to estimate the pattern of ecological security (ES) in PRD, China. • Hot and cold spots for the spatial distribution of ES were identified. • Optimal management was proposed from three categories for each municipality. • The main factors influencing ES distribution were explored using semivariance. The ecological security (ES) pattern in China is gaining considerable attention worldwide due to intensifying urban development and human activities that threaten ecosystem structures and ecological processes. The Pearl River Delta (PRD) has experienced intense economic development for nearly 40 years; however, the ES pattern in the PRD is poorly understood. In this paper, we used a multisource data approach to assess ES, performed downscaling to a 1 × 1 km2 grid size, and applied spatial statistics to analyze the ES pattern in the PRD. We found three natural "ecological buffers," namely, nature reserves and forest patches covering several municipalities in the delta, thus guaranteeing the socio-economic development of this highly urbanized area. The spatial autocorrelation results indicated that the ES pattern is significantly spatially correlative (p = 0.001), with a Moran's I of 0.7766. We identified several hot and cold spots for the ES spatial distribution that occupied 58.49% of the PRD's total area. Moreover, a semivariance analysis showed that structural factors are dominant in the ES spatial distribution. Based on the ES area proportions, the 9 municipalities of the PRD can be grouped into three categories: optimized development zones, comprehensive development zones, and ecological conservation development areas. Zhaoqing, Huizhou and Jiangmen are key areas for improving ES conservation in the PRD. In this study, we explore an ES assessment model coupled with a spatial heterogeneity analysis to provide insights into ecological conservation efforts in urban agglomerations. [ABSTRACT FROM AUTHOR]

Neotectonics and active tectonics are sub-disciplines of tectonics that study the process of recent tectonic deformation and tectonic geomorphic evolution on the Earth. The time scale of neotectonics research is closely related to the geodynamics of a specific region; it typically concerns geological processes at time scales from Ma to ka, and emphasizes on the relationship between the past and present tectonic deformation. On the other hand, research in active tectonics pays greater attention to geological–geomorphological processes since 100˜150ka, and focuses on present and future tectonic deformation. Research on neotectonics and active tectonics for seismic hazard assessment is a significant aspect of earthquake geology work. This, along with other related researches, is the primary basis of earthquake forecasting and prediction, urban and rural earthquake prevention, disaster mitigation, and project planning and design for effective circumvention and mitigation of geological hazards caused by active faults. Recent advances in these fields have indicated that the fast development and application of Quaternary chronology, open access space observation, and geographic information system (GIS), have substantially increased the level and precision of quantitative research on neotectonic evolution, tectonic morphology, fault activity and palaeo-seismology. This has led to the promotion and growth of digitalization and sharing of active fault data, and has also improved the reliability and accuracy of seismic hazard assessment. However, in countries and areas with high density of active faults and complex tectonic systems, such as China, research on neotectonics and active tectonics for seismic hazard assessment needs to be even further strengthened. There is a need for fast and effective regional surveying of active faults by the use of remote sensing and Digital Elevation Models (DEM) imaging, so as to study active structural systems. Therefore, to consolidate the geological foundation for prevention and mitigation of seismogeological disasters. Besides, the relationship between fault activity and risk should be distinguished, and attention should be paid to areas having strong-earthquake risk in stable continental regions and having low-slip-rate faults. [ABSTRACT FROM AUTHOR]

• The built-up land of the Pearl River Delta was increased by 174 % from 1985 to 2015. • Built-up land is the main threat to regional ecological security. • Combining habitat quality and landscape ecological risk to identify zonal of ecological security. • Early warning zones and suggestions for future urban growth were provided. The Pearl River Delta (PRD) has experienced rapid urbanization processes for nearly 40 years. Due to the high population densities and developed industries, the region will continue to expand. To explore the impact of future land-use change on land ecological security, a regional ecological security early warning (ESEW) was spatially constructed by overlaying the simulated future built-up land with the current ecological security partition zones. The results showed that (1) the habitat quality was severely degraded in Pearl River Delta and the spatial differentiation was obvious, showing low habitat quality in the middle and high quality in the east and west; (2) the landscape ecological risk showed an increasing trend and the area of higher risk increased from 0.8 % to 7.4 % of the total area of the Pearl River Delta from 1985 to 2015; (3) each ecological security partition zone changed in different directions, and zone V changed from a single core to a multicore; (4) in the scenario of coordinated development under a balanced environment and economy, an equilibrium of each early warning level of ecological security will be reached. These results provide a reference for land-use planning, urban master planning and management decisions. [ABSTRACT FROM AUTHOR]

There is a significant challenge in resource management: the perceived trade-off between economic growth and ecosystem conservation. In this study, we integrate a variety of quantitative research methods and models, such as the ecosystem service value (ESV), interval parameter planning (IPP), Dyna-CLUE, and Monte Carlo methods, in an attempt to balance the ESV and economic benefits. The highest system benefits can be obtained, and uncertainty in the ecosystem assessment is considered. Taking the Pearl River Delta as the study area, the results show that when the GDP growth rate is less than 6%, the ESV in 2025 will be higher than the ESV in 2017. An interval approach (upper and lower bounds) is used. For a scenario with a 5% GDP growth rate, the ESV is RMB¥ [1.85, 20.79] × 109, which is more than the ESV of the scenario with a 9% GDP growth rate. When the GDP growth rates are 5% and 9%, the proportions of forestland are [61.5%, 61.7%] and [58%, 58.2%], respectively. Furthermore, spatialization was performed using the Dyna-CLUE model. In 2025, the simulated area of farmland is larger in some small regions with 9% GDP growth rate than it is in regions with 5% GDP growth rate, thus achieving a balance between occupation and compensation of regional farmland. By comparing ecosystem planning under different GDP growth rates, an optimized land-use allocation method can help decision makers balance system benefits and ecological risks, which can provide multiple options and specific locations for decision. Image 1 • A model was built to balance ecosystem services (ES) and economic benefits. • An evaluation system was built to assess the ESV in the lower and upper bounds. • Spatial differences in both ESV and land-use efficiency are considered. • An interval parameter planning (IPP) method and Dyna-CLUE model are integrated. • Decision makers are supported to balance system benefits and ecological risks. [ABSTRACT FROM AUTHOR]

• The landscape pattern of the Pearl River Delta (PRD) is gradually fragmented. • Integrated SD-CA model was better modeled in the PRD. • The scenario of coordinated development for the PRD was recommend. • Urban management and planning optimization management measures was provided. Land-use and land-cover change (LUCC) is directly related to human activities. Simulating the process of LUCC and predicting the future changes are important. The system dynamics (SD) model, grey prediction (GM) model and Markov model were applied to the simulation. From 1985–2015, the cropland decreased by 20.83% in the Pearl River Delta (PRD), and construction land increased by 173.61%. The SD model obtained an optimal result. The simulation processes revealed that social and economic factors have a great impact on LUCC processes. The SD model is an optimal quantitative model when combined with the cellular automata (CA) model to simulate spatial dynamics of LUCC (kappa index = 0.94 in 2015). Three scenarios were used and related to rapid development, coordinated development, and conservation. A good development scenario with lower fragmentation and highest connectivity in a landscape in the PRD was achieved under the coordinated development scenario. The SD-CA model has advantages due to its inclusion of many social and policy factors. This study shows that the SD-CA model under the coordinated development scenario provides the best result for the PRD. [ABSTRACT FROM AUTHOR]

[Display omitted] • Soil silt/clay and nutrients increased with increasing distance from the shelterbelt. • Downslope deposition lead to an increase in plow pan thickness and a decrease in bulk density. • Erosion rate was primarily affected by shelterbelt distance, followed by elevation. • Sites closer to shelterbelt warrant particular attention due to coarse-texture materials. Soil erosion is the most severe form of land degradation globally. Farmland shelterbelts are important for reducing erosion, especially erosion caused by the co-occurrence of water and wind. However, few studies have focused on how the distance from the shelterbelt associated with farmland topography affects the redistribution of soil quality indicators. The aims of this study is to reveal the relative importance of these two factors to soil quality under typical wind and water erosion conditions concurrent with the Songnen Plain, China. Topsoils (0–10 cm) were sampled at seven distances from the shelterbelt with three replicates, where topography heterogeneity was also considered. We found that the silt/clay content and soil nutrients at sites farther from the shelterbelt were significantly greater than those at sites closer to the shelterbelt (P < 0.05). Similarly, deposition was dominant at sites farther from the shelterbelt and downslope positions, while erosion was dominant at sites closer to the shelterbelt and upslope positions. Moreover, we discovered that the relative influence of distance from the shelterbelt and farmland elevation varied with individual soil quality indicators. Soil nutrients increased through the deposition of more fine-textured soil (silt/clay) positions farther from the shelterbelt. The downslope region responds to soil deposition by enhancing the plough pan thickness and lowering the bulk density and pH. Overall, distance from the shelterbelt and farmland elevation had interactive effects on soil quality, and erosion was primarily affected by distance from the shelterbelt (63.4 %), followed by elevation (22.7 %). Furthermore, the sites closer to the shelterbelt (i.e., 20 to 420 m) warrant particular attention due to the deposition of coarse-texture materials here. This work is crucial for an improved understanding of the synergistic effects of long-term water and wind co-occurrence on soil quality evolution. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ecological sources were identified using morphological spatial pattern analysis. • Resistance surface was developed from ecosystem service value. • Ecological corridors were identified using minimum cumulative resistance model. • The ecological network was optimized by similarity search. Ecological infrastructure is a popular framework for conservation planning. In this paper, one of the most urbanized regions of China-Shenzhen was chosen as the study area. Ecological infrastructure with different configurations and functions were identified and combined to form the urban ecological network. The ecological sources were identified using morphological spatial pattern analysis (MSPA) and landscape connectivity analysis. The ecological resistance surface developed from ecosystem service value was modified basing on ecological sensitivity and landscape connectivity. The ecological network was constructed by minimum cumulative resistance (MCR) model and then optimized and accessed. The results show that: (1) the ecological network consists of 25 ecological sources distributed mainly in the southeast and west. Twenty-nine ecological corridors were extracted and 36 ecological nodes identified. (2) In the optimized ecological network, 10 new ecological sources were added, and 46 ecological corridors and 59 ecological nodes were identified. It would promote the connectivity of the ecological sources and the stability of ecological functioning process. (3) The ecological network took ecosystem service value and ecological sensitivity into consideration and lays emphasis on improving landscape connectivity, providing an approach to optimizing urban ecological network and contributing to urban planning. [ABSTRACT FROM AUTHOR]

The ecological security pattern (ESP) focuses on key ecological elements in ecosystems by identifying, combining, and evaluating these elements. This study attempts to identify the ESP of the Pearl River Delta (PRD) and provide suggestions for optimization. Ecosystem services were calculated and applied to construct the ecological resistance surface; morphological spatial pattern analysis (MSPA) and landscape connectivity analysis were used to identify ecological sources; and minimum cumulative resistance (MCR) model was applied to extract ecological corridors and ecological nodes. The results show that during 1995 to 2015, the main landscape transformation occurred between forest, cropland, and urban land, and the location of the transformation was mainly in the central part of the study area. Regarding the ESP, the average resistance value increased from 0.30 to 0.33; the area of ecological sources decreased by 5.12%; the ratio of total cumulative resistance to the length of the corridors increased by 14.82%; and the number of ecological nodes increased from 71 to 99. For the ESP optimization, based on the correction of the resistance surface, 1348 km blue corridors and 61 blue nodes were extracted. Based on hot spot analysis, nine stepping stones were identified. This optimization compensates for the lack of ecological elements in the center of the study area, enhances weaker corridors, and improves the connectivity of the ESP, thus making the ESP more stable and complete. The ESP constructed and optimized in this paper holds great significance and serves as a valuable reference for ecological protection and environmental management., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)