The Xujiaweizi fault depression is located in the northern part of the Songliao Basin, China. The Yingcheng Formation of the Xujiaweizi fault depression is a fractured tight volcanic reservoir. Many primary pores exist in the tight volcanic reservoirs of the Yingcheng Formation, but their connectivity is very poor. The degree of development of tectonic fractures determines the reservoir quality and the probability of hydrocarbon accumulation. To elucidate the fracture characteristics and their effects on hydrocarbon migration and accumulation, we analyze the fracture genetic types, characteristics, and controlling factors using data from cores, image logs, and thin sections. Then, we evaluate the matching relationship between tectonic fractures and hydrocarbon migration and accumulation by combining the evolution of the source rocks, analysis of the gas-source fault activity period and evolution of the cap rock sealing ability. We find two types of fractures developed in tight volcanic rocks: primary fractures and secondary fractures. Primary fractures mainly include cooling contraction fractures and cryptoexplosive fractures. Secondary fractures could be further divided into tectonic fractures, dissolution fractures, and weathering fractures. Among them, tectonic fractures are dominant. The distribution of tectonic fractures is controlled by lithology, lithofacies, faults, rock anisotropy, and an unconformity. Tectonic fractures are mainly formed in three phases. The time when the second phase of tectonic fractures formed (the Late Quantou-Qingshankou period) coincided with the peak hydrocarbon generation of the source rocks of the Shahezi Formation. Also at that time, the gas-source faults were active and the cap rock had a good top-seal capacity. Thus, the Late Quantou-Qingshankou period was the main period of natural gas accumulation.
The urban water environment is seriously affected by human activities. Rivers in highly industrialized areas, which often carry various types of industrial pollutants, such as metals and nutrients, are especially affected. In this study, the water quality of the Pi River, an industrial base that flows through Chengdu, a large city in Southwest China, was tested for one year. Heavy metal concentrations in the water, sediment, and macrobenthic and algal communities in the river were examined. The water pollution index (WPI) and trophic level index (TLI) were employed to measure the water pollution degree and eutrophication status, respectively. The Shannon—Wiener index (H’) and Margalef’s index (dM) were determined to represent the diversity and richness of macroinvertebrates. The principal component analysis (PCA) was employed to define the main heavy metal influencing factors in the Pi River. Our study showed that the eutrophication status increased with spatial change, and the eutrophication status was the most serious in the downstream reach, which was moderately eutrophic. The water body of the Pi River was seriously polluted by heavy metals, and the content of chromium (Cr) in the sediment and cadmium (Cd) in the water/sediment was far beyond the prescribed limit. In addition, we found that Cd had a serious impact on both the benthic and algal communities, and the benthic community structure was completely changed, destroying the original aquatic environment. We explored the mechanisms of the influence of Cd on aquatic fauna, and this information is of great significance for the future conservation of industrial urban rivers. In this study, the spatial–temporal variations in water quality and aquatic communities revealed the pollution status of a river flowing through industrial areas, which provided a basis for future river conservation and restoration.
Forest therapy is a fast-growing treatment approach, as it has the potential to alleviate stressful life events and to improve psychological well-being and physical health. Bamboo forests are widespread in southwestern China. Nevertheless, a knowledge gap on the specific health benefits of bamboo forest (BF) therapy still exists. To explore the psycho-physiologic responses of participants to the effects of BF therapy, 60 male adults aged between 19 and 24, with similar healthy conditions, were selected to participate in this study. A one-group pretest–posttest design was used for the BF sites and the city site (CS) to compare the difference in the psycho-physiologic responses of participants before and after the test. Participants at the BF sites participated in a three-day bamboo forest therapy session, and those at the CS participated in a three-day urban program. Blood pressure, heart rate, and peripheral oxygen saturation were measured as the physical signs, and the profile of mood state (POMS) questionnaire was completed by the participants for the psychological evaluation. Blood was sampled, and natural killer (NK) activity, the number of NK cells, and the levels of corticosterone, granulysin, perforin, and granzyme A/B in peripheral blood lymphocytes (PBLs) were measured. All the measurements mentioned above were performed at 08:00 on the first and fourth days within the test. Results indicated that the three-day BF therapy was capable of enhancing positive mood states and also reducing negative mood states in the male participants. The blood pressure and heart rates of the male participants decreased, while the peripheral oxygen saturation increased after the three-day BF therapy session. Furthermore, BF therapy significantly increased NK activity and the number of NK cells and perforin-, granulysin-, and granzyme A/B-expressing cells and significantly decreased the corticosterone level in PBLs in the male participants. The three-day BF therapy session improved the psychological and physiological well-being and enhanced the immune functions of the male college students.
Studies have indicated that natural environments have the potential to improve the relationship between a stressful life and psychological well-being and physical health. Forest therapy has recently received widespread attention as a novel solution for stress recovery and health promotion. Bamboo is an important forest type in many countries, especially in East and Southeast Asia and in African countries. Bamboo is widespread throughout southwestern China. Empirical field research on the physiological effects of bamboo forest therapy is currently lacking. To explore the benefits of bamboo forest therapy on the physiological responses of university students, 120 university volunteers between the ages of 19 and 24 participated in this study (60 males and 60 females) and were randomly divided into four groups of equal size (15 males and 15 females in each). Four sites were selected for the experiment, including two natural bamboo forests (YA and YB), a bamboo forest park (DJY), and an urban environment (CS). During the testing period, all participants were asked to view the landscape for 15 min in the morning and then walk in the testing area for 15 min in the afternoon. Blood pressure (BP), heart rate (HR), and peripheral oxygen saturation (SpO2) were measured as the physiological indexes, and the semantic differential method (SDM) questionnaire was completed for the environmental satisfaction evaluation. The SDM for the subjective environmental evaluation differed significantly among the university students; they obtained a better environmental experience, in terms of sensory perception, atmosphere, climate, place, and space, in the bamboo forest sites. The three-day bamboo forest therapy session improved the physiological well-being of university students. First, the blood pressure and heart rate of the university students decreased, and the SpO2 increased, after the three-day viewing and walking activities of the three-day bamboo forest therapy session. The viewing activities had a more pronounced effect on decreased heart rate in university students. Additionally, three-day bamboo forest therapy had a positive impact on decreased systolic blood pressure and heart rate in the university students, and it was significantly decreased in females, while peripheral oxygen saturation (SpO2) remained relatively low. Finally, compared with the urban site (CS), the bamboo forest sites effectively improved the university students’ physiological state of health, decreased their physical pressure, and stabilized their physiological indicators. These findings provide scientific evidence that a three-day bamboo forest therapy session can increase positive physiological responses. The potential for a longer-term effect on human physiological health requires further investigation.
The ecological environments of urban rivers are greatly affected by human activities, leading to serious water quality deterioration. We thus investigated urban aquatic environment and water pollution factors by collecting water samples over one year upstream, midstream and downstream of the Funan River in Chengdu, Sichuan, China. Measured water quality indicators included total N/P ratio, ammonia N, chemical oxygen demand, chlorophyll a, biochemical oxygen demand, transparency, turbidity, dissolved oxygen, conductivity, and pH, as well as the heavy metal concentrations and algal communities in the river sediments. Additionally, a water pollution index (WPI) and trophic level index (TLI) were calculated and a principal component analysis (PCA) was performed. The WPI analysis indicated serious pollution in this river during the sampling year. Moreover, moderate eutrophication with high pollution was found in summer (TLI = 64.7), while mild eutrophication occurred in the other seasons. The number of Cyanobacteria species sharply increased from 6 to 23 in summer, indicating a high risk of blooms. Furthermore, the PCA also revealed that two metals, chromium and cadmium, affected the water quality, which may be because of the interaction of nutrients and metals due to the land use types, industrial activities and hydrodynamic conditions. In general, we have systematically discussed the influences of various factors on the water environment and the mechanisms of their interactions in urbanized rivers, which is very important for the protection and restoration of river ecology as China and the world become more urbanized.
Phytoremediation is an effective way to remediate metal-contaminated soils. During phytoremediation, plants immobilize heavy metals through the roots to reduce the mobility, toxicity and dispersal of the metals, and the changes in the activity of the roots are often accompanied by changes in the rhizosphere ecosystems, in which rhizobacteria are essential components and interact with roots to maintain the stability of the rhizosphere ecosystem and improve soil health. In this study, the phytoremediation potential of Sasa argenteostriata (Regel) E.G. Camu and the response of rhizobacteria were revealed with different levels of lead-zinc tailing contamination (Pb, Zn, and Cd concentrations of 1197.53, 3243.40, and 185.44 mg/kg for M1 and 2301.71, 6087.95, and 364.00 mg/kg for M2, respectively). The BCF of Sasa argenteostriata increased with increasing soil pollution, and the BCFPb, BCFZn, and BCFCd were 0.19, 0.27, and 0.08, respectively, under the M2 treatment; in contrast, the TF decreased with increasing soil pollution, and the TFPb, TFZn, and TFCd were 0.39, 0.85, and 0.07, respectively, under the M1 treatment. The mobility of Pb in the rhizosphere was higher than that of Zn and Cd, and the percentage of residual (Res) Zn and Cd in the rhizosphere increased, while the acid-soluble (Aci) Pb was significantly higher, leading to obvious uptake of Pb by the roots. Correlation analysis showed that Sasa argenteostriata affected the rhizobacterial community by changing the rhizosphere soil pH, the contents of organic matter and NRFM, and bacteria such as Proteobacteria and MND1, which are highly resistant to heavy metals (HMs), became the dominant species in the community. Further PICRUSt2 analysis showed that reducing metal transport across the membranes and increasing the efficiency of cellular reproduction were the main metabolic mechanisms of bacterial tolerance to HMs. Overall, the roots of Sasa argenteostriata were able to immobilize more heavy metals in PbZn tailing-contaminated soil, reducing the toxicity of HMs in the soil, and then influencing the rhizobacteria to change the community structure and metabolism mechanism to adapt to the HM-contaminated environment, and the soil fertility was increased, which together promoted the health and stability of the soil. This study is the first to illustrate the phytoremediation potential and response of the rhizobacterial community of Sasa argenteostriata under multimetal contamination of PbZn tailings. The results of the study provide some guidance for the practice of lead-zinc tailing-phytoremediation and soil health.
Forests are large-scale green space resources that may exert a positive impact on human physiology and psychology. Forests can be divided into mixed forest and pure forest, according to the number of dominant tree species. Pure forest offers specific advantages for the study of spatial structure and scale. In this study, a type of pure forest (i.e., bamboo forest) was adopted as a research object to investigate differences in the physiological and psychological responses of psychologically pressured college students to different types of forest space. We recruited 60 participants and randomly assigned them to three experimental groups: forest interior space (FIS), forest external space (FES) and forest path space (FPS). All participants were asked to perform the same pre-test task but different post-test tasks. The pre-test involved performing a pressure-inducing task, whereas the post-test involved viewing photographs of each space type. The same indicators were measured in both the pre- and post-test, including a β/α index from each lobe, positive emotion, negative emotion and total mood disturbance (TMD) values, according to the profile of mood states (POMS), in addition to spatial scale preferences obtained through a questionnaire and interviews. We analysed brain waves and mood indicators through analysis of covariance (ANCOVA), whereby the FES group exhibited the best physiological and psychological relaxation effect. The FPS group displayed a medium effect, and the FIS group exhibited the worst effect. Analysis of variance (ANOVA) was used to analyse the spatial scale scores. The FPS and FES types achieved a higher spatial scale preference scores than the FIS type. Based on a comparison of the psychophysiological results with the spatial scale preference results, spatial structure and scale are considered to be important intrinsic factors that influence the health effects of pure forest. The results can provide guidance for forest-related human health activities and their management.