Peanut Rotation and Flooding Induce Rhizobacteriome Variation With Opposing Influences on the Growth and Medicinal Yield of Corydalis yanhusuo

Corydalis yanhusuo, a precious herb of the Papaveraceae family, is widely used in multiple traditional Chinese medicines for the treatment of many painful conditions, and its medicinal part is the dried tuber. Yet how to improve this plant’s medicinal yield as well as its economic efficiency remains a key problem in its cultivation. The planting of C. yanhusuo in rotation with peanut (Arachis hypogaea L.) aims to improve land utilization efficiency, but the total production of tubers is severely reduced relative to fields without rotation. However, an increased yield was observed in C. yanhusuo plants grown in previously flooded fields (HR field) compared to the ones grown in the fields that had been used to cultivate peanut (PL field) or in fields without rotation or flooding (N field). Based on these phenomena, in this study, we explored the potential factors responsible for the altered growth/yield of C. yanhusuo under different field conditions. Soil physicochemical properties and the diversity and community of rhizobacteriome of C. yanhusuo were both analyzed. By testing several soil physicochemical properties, we found that the cation exchange capacity (CEC), soil organic matter (SOM), total nitrogen (TN), and pH value differed significantly among these three types of fields. 16S rRNA amplicon sequencing revealed stark differences in the composition, diversity, and potential functions of the bacterial community in the rhizosphere of C. yanhusuo plants grown in field with the peanut rotation or flooding. Notably, the Acidobacteria were enriched in the HR field, while Actinobacteria were enriched in the PL field. More importantly, further analysis showed that changed soil physicochemical properties could be one reason for why the rhizospheric bacterial community has changed; hence, soil physicochemical properties might also be affecting plant performance indirectly by regulating the rhizospheric bacterial community. The RDA analysis distinguished CEC as the most important soil physicochemical property influencing the structure and composition of the C. yanhusuo rhizobacteriome. In summary, our results suggest peanut rotation- and flooding-induced soil physicochemical properties changes would further impact the rhizobacteriome of C. yanhusuo albeit differentially, culminating in opposite effects upon the plant growth and medicinal yield of C. yanhusuo.

Source Apportionment and Geographic Distribution of Heavy Metals and as in Soils and Vegetables Using Kriging Interpolation and Positive Matrix Factorization Analysis

Food security and cultivated land utilization can be seriously affected by heavy metal (HM) pollution of the soil. Therefore, identifying the pollution sources of farmland is the way to control soil pollution and enhance soil quality effectively. In this research, 95 surface soil samples, 34 vegetable samples, 27 irrigation water samples, and 20 fertilizer samples were collected from the Wuqing District of Tianjin City, China and was used to determine their HMs accumulation and potential ecological risks. Then, kriging interpolation and positive matrix factorization (PMF) were utilized to identify the sources of soil HMs. The results indicated that soil HMs in the study area were contaminated at a medium level, but that the pollution of Cd was more severe, and the Cd content in vegetables was slightly higher than the permissible threshold (0.02 mg·kg−1). Furthermore, a non-homogeneous distribution was observed, with higher concentrations of HM contaminants concentrated in the southwest of the study area, where many metal manufacturing industries are located. Our results suggest that the Cd originated from industrial activity; As and Pb from agricultural practices; Ni, Cu, Cr, and As mainly from natural sources; Zn and Cu from organic fertilizer; Pb and Cd mainly from traffic discharge; and Cr, Ni, and Pb from sewage irrigation. Obviously, the accumulation of soil HMs in the study area could be mainly attributed to industrial activities, implying the need for implementation of government strategies to reduce industrial point-source pollution.

Integrative Physiological, Transcriptional, and Metabolic Analyses Provide Insights Into Response Mechanisms of Prunus persica to Autotoxicity Stress

Autotoxicity is known as a critical factor in replanting problem that reduces land utilization and creates economic losses. Benzoic acid (BA) is identified as a major autotoxin in peach replant problem, and causes stunted seedling growth or even death. However, the physiological and molecular mechanisms of peach response to BA stress remain elusive. Here, we comprehensively studied the morphophysiological, transcriptional, and metabolic responses of peach plants to BA toxicity. Results showed that BA stress inhibited peach seedlings growth, decreased chlorophyll contents and fluorescence levels, as well as disturbed mineral metabolism. The contents of hydrogen peroxide, superoxide anion, and malondialdehyde, as well as the total antioxidant capacity, were significantly increased under BA stress. A total of 6,319 differentially expressed genes (DEGs) were identified after BA stress, of which the DEGs related to photosynthesis, redox, and ion metabolism were greatly changed; meanwhile, numerous stress-responsive genes (HSPs, GSTs, GR, and ABC transporters) and transcription factors (MYB, AP2/ERF, NAC, bHLH, and WRKY) were noticeably altered under BA stress. BA induced metabolic reprogramming, and 74 differentially accumulated metabolites, including amino acids and derivatives, fatty acids, organic acids, sugars, and sugar alcohols, were identified in BA-stressed roots. Furthermore, an integrated analysis of genes and metabolites indicated that most of the co-mapped KEGG pathways were enriched in amino acid and carbohydrate metabolism, which implied a disturbed carbon and nitrogen metabolism after BA stress. The findings would be insightful in elucidating the mechanisms of plant response to autotoxicity stress, and help guide crops in alleviating replant problem.

Analysis of Disaster Mitigation in Carita with Environmental Learning in Elementary School

This study analyzes the profile of Carita people in the efforts of tsunami disaster mitigation and the role of environmental learning in coping with the disaster, then analyzes the use of environmental learning. The method used is a mixed method of qualitative and quantitative methods. The quantitative method measures various community readiness levels in performing disaster mitigation, whereas the qualitative method is utilized to obtain various further information from the communities using interview technique. There were 88 randomly selected respondents participating in this research. The study results indicate a low land utilization density (below 33%). Indicators suggest a good category, namely: people evacuate when a disaster occurs (86%), rescue during a disaster (96.59%), and try to find new livelihoods (82.95%). In addition, public knowledge of disaster evacuation route is at a good level (87.50%) and there is an increase of 39.77% respondents with improved knowledge after the tsunami disaster occurred. Environmental learning, in this case, plays an important role to provide information to the public relating the efforts in disaster mitigation. The conclusion is that community’s disaster mitigation readiness still requires some improvement through various efforts, one of them is environmental learning with learning media in elementary school.

Assessment of Groundwater Vulnerability using COP Method to Support the Groundwater Protection in Karst Area

The karst landform holds considerable water resource potential and is known for its underground rivers. On the other hand, the high porosity carbonate rocks on this landform cause the decrease of the natural protection function against groundwater pollution. Hence, the analysis of groundwater vulnerability in the karst area is prominent before making the spatial planning regulation. This recent study aimed to analyze the groundwater vulnerability in the karst area located in a part of Umbulrejo Village, Yogyakarta, Indonesia, and proposed action in groundwater protection. The method used in this research was based on the COP method. The data acquisition was conducted by survey method both for primary and secondary data. The COP (Concentration of flow, overlaying layers, and precipitation) analysis was supported by ArcGis software. The analysis of groundwater vulnerability showed that there were two vulnerability classes, i.e., very high (48.6%) and high (51.4%). These results were influenced mainly by the close distance of the recharge area to swallow holes and the lithology type (karst), which contributed to a very high value in reducing protection against groundwater. A proposed action to support groundwater protection is regulating the land utilization in the area of the settlements.

Ionomic and Metabolomic Analyses Reveal Different Response Mechanisms to Saline–Alkali Stress Between Suaeda salsa Community and Puccinellia tenuiflora Community

Soil salinization imposes severe stress to plants, inhibits plant growth, and severely limits agricultural productivity and land utilization. The response of a single plant to saline-alkali stress has been well investigated. However, the plant community that usually works as a group to defend against saline–alkali stress was neglected. To determine the functions of plant community, in our current work, Suaeda salsa (S. salsa) community and Puccinellia tenuiflora (P. tenuiflora) community, two communities that are widely distributed in Hulun Buir Grassland in Northeastern China, were selected as research objects. Ionomic and metabolomic were applied to compare the differences between S. salsa community and P. tenuiflora community from the aspects of ion transport and phenolic compound accumulation, respectively. Ionomic studies demonstrated that many macroelements, including potassium (K) and calcium (Ca), were highly accumulated in S. salsa community whereas microelement manganese (Mn) was highly accumulated in P. tenuiflora community. In S. salsa community, transportation of K to aboveground parts of plants helps to maintain high K+ and low Na+ concentrations whereas the accumulation of Ca triggers the salt overly sensitive (SOS)-Na+ system to efflux Na+. In P. tenuiflora community, enrichment of Mn in roots elevates the level of Mn-superoxide dismutase (SOD) and increases the resistance to saline–alkali stress. Metabolomic studies revealed the high levels of C6C1-compounds and C6C3C6-compounds in S. salsa community and also the high levels of C6C3-compounds in P. tenuiflora community. C6C1-compounds function as signaling molecules to defend against stress and may stimulate the accumulation of C6C3C6-compounds. C6C3-compounds contribute to the elimination of free radicals and the maintenance of cell morphology. Collectively, our findings determine the abundance of phenolic compounds and various elements in S. salsa community and P. tenuiflora community in Hulun Buir Grassland and we explored different responses of S. salsa community and P. tenuiflora community to cope with saline–alkali stress. Understanding of plant response strategies from the perspective of community teamwork may provide a feasible and novel way to transform salinization land.

The Construction of Ecological Security Patterns in Coastal Areas Based on Landscape Ecological Risk Assessment—A Case Study of Jiaodong Peninsula, China

Increasing land utilization, population aggregation and strong land–sea interaction make coastal areas an ecologically fragile environment. The construction of an ecological security pattern is important for maintaining the function of the coastal ecosystem. This paper takes Jiaodong Peninsula in China, a hilly coastal area, as an example for evaluating landscape ecological risk within a comprehensive framework of “nature–neighborhood–landscape”, based on spatial principal component analysis, and it constructs the ecological security pattern based on the minimum cumulative resistance model (MCR). The results showed that the overall level of ecological risk in the study area was medium. The connectivity between the areas of low landscape ecological risk was relatively low, and the high risk areas were concentrated in the north of the Peninsula. A total of 11 key ecological corridors of three types (water, green space and road corridors) and 105 potential corridors were constructed. According to the ecological network pattern, landscape ecological optimization suggestions were proposed: key corridors in the north and south of Jiaodong Peninsula should be connected; urban development should consider current ecological sources and corridors to prevent landscape fragmentation; and the ecological roles of potential corridors should be strengthened. This paper can provide a theoretical and practical basis for ecological planning and urban master planning in coastal areas in the future.

Facilitating informed land-use decisions through the modelling of ecosystem service trade-offs

<p>Increasing global populations are placing increasing pressure on our natural systems, reducing their capacity to produce the ecosystem services that we rely upon for human wellbeing (World Bank, 2004). Clarifying the implications of land-use decisions across the range of ecosystem services is fundamental to understanding the trade-offs inherent in land-use options. LUCI (the Land Utilization and Capability Indicator) is an emergent Geographic Information Systems (GIS) based framework developed to enable the mapping of several ecosystem services in a spatially explicit manner. This process enables a clearer understanding of the inter-dependencies between ecosystems and potential implications and trade-offs of management interventions across a range of services. There is however, limited understanding of the impact, utility and credibility of such tools for land-use decision-makers, or of how they perceive the information conveyed. This Thesis considered the impact that presenting information on land-use trade-offs through LUCI had on land-owners at the farm scale. This research supports previous findings that information alone does not drive behaviour (or decision-making) (Kollmuss, 2002, Fisk, 2011; Kennedy, 2010; Mackenzie-Mohr, 2000; Stern, 2000). Similarly, perceived credibility was not the main driver of decision-making nor is it necessarily rationally based. However without it, voluntary adoption of a new technology or tool is unlikely. Therefore, in seeking to diffuse tools, such as LUCI within a community, process design should take into account the social structures and the characteristics of targeted individuals within that community. The influence of temporal and context specific factors on decision-making provides both barriers and opportunities for technology diffusion. The research findings propose that when integrating new tools and technologies within communities, consideration is given to using a suite of tools, mechanisms and theories in concert such as Community-Based Social Marketing (Mackenzie-Mohr, 2011) and Diffusion Theory (Rogers, 2003) to facilitate improved diffusion and uptake by communities.</p>

Facilitating informed land-use decisions through the modelling of ecosystem service trade-offs

<p>Increasing global populations are placing increasing pressure on our natural systems, reducing their capacity to produce the ecosystem services that we rely upon for human wellbeing (World Bank, 2004). Clarifying the implications of land-use decisions across the range of ecosystem services is fundamental to understanding the trade-offs inherent in land-use options. LUCI (the Land Utilization and Capability Indicator) is an emergent Geographic Information Systems (GIS) based framework developed to enable the mapping of several ecosystem services in a spatially explicit manner. This process enables a clearer understanding of the inter-dependencies between ecosystems and potential implications and trade-offs of management interventions across a range of services. There is however, limited understanding of the impact, utility and credibility of such tools for land-use decision-makers, or of how they perceive the information conveyed. This Thesis considered the impact that presenting information on land-use trade-offs through LUCI had on land-owners at the farm scale. This research supports previous findings that information alone does not drive behaviour (or decision-making) (Kollmuss, 2002, Fisk, 2011; Kennedy, 2010; Mackenzie-Mohr, 2000; Stern, 2000). Similarly, perceived credibility was not the main driver of decision-making nor is it necessarily rationally based. However without it, voluntary adoption of a new technology or tool is unlikely. Therefore, in seeking to diffuse tools, such as LUCI within a community, process design should take into account the social structures and the characteristics of targeted individuals within that community. The influence of temporal and context specific factors on decision-making provides both barriers and opportunities for technology diffusion. The research findings propose that when integrating new tools and technologies within communities, consideration is given to using a suite of tools, mechanisms and theories in concert such as Community-Based Social Marketing (Mackenzie-Mohr, 2011) and Diffusion Theory (Rogers, 2003) to facilitate improved diffusion and uptake by communities.</p>