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Balancing economic, environmental and social objectives usually challenges policymakers, but it is feasible. Using a unique household survey dataset with 98 households in Ca Mau Province, Vietnam, we found that integrating mangroves with shrimp farming, in a mangrove-aquaculture system (MAS), can support multiple objectives. The MAS provides the highest average benefit-cost ratio (BCR), from 2.7 to 2.9, while the BCR of surveyed intensive shrimp farms ranged from 1.1 to 1.2, and that of the traditional extensive shrimp farming systems was from 1.7 to 1.8. MAS was also the least expensive in terms of investment and suitable for people with limited financial capacity. MAS can also produce other economic and environmental benefits, such as from carbon mitigation, with less overall risk than the other systems. Our survey data show that mangrove coverage may contribute to economic efficiency; and the optimal mangrove coverage from the perspective of individual farmers (30%) was lower than what is demonstrated by empirical data (60%). While our findings draw from survey data in a specific location, they highlight the benefits of MAS as a possible triple-win approach towards sustainable development and also emphasise the importance of complementary programs, such as awareness enhancement, communication, and training.

Cultivation of crops in salt-affected soils is a major challenge for growers. Despite the use of multiple amendments, salinity stresses adversely affect the crops to some extent. On the other hand, imbalance in the use of boron (B) as a nutrient also creates toxicity. Mismanagement of B fertilizer application decreases the growth and yield of crops. It is necessary to study in depth the adverse effects of salinity and B toxicity. This is why the current research work was conducted in a glass house at Murdoch University, Perth, Australia. The aim of study was to investigate the influence of salinity and B toxicity on carbohydrate partitioning, growth, and ionic composition of two Australian wheat varieties. There were four treatments, i.e., control, high B (15 kg ha−1), salinity (15 dS m−1), and B + salinity. The results showed that the salt-tolerant Halberd (HB) variety accumulated more Na+, B, and Cl− in their leaf sheath and kept the leaf blades free of these toxic ions as compared to the sensitive variety Westonia (WS). Water-soluble carbohydrate (WSC; i.e., glucose, sucrose, fructose, and fructans) concentration increased in response to individual as well as combined constrains of soil salinity and toxic B in the leaf blade of both tolerant and sensitive wheat varieties, but the increase was higher in the tolerant variety as compared to the sensitive one. The concentration of WSCs in leaf sheath of the salt-tolerant wheat variety was increased in response to stress conditions, but those remained low in salt-sensitive ones. Therefore, the salt-tolerant HB genotype was found to be a good source for future wheat breeding programs or to be grown by farmers in B toxic, saline, and B toxic–saline conditions.

Increased heat in urban environments, from the combined effects of climate change and land use/land cover change, is one of the most severe problems confronting cities and urban residents worldwide, and requires urgent resolution. While large urban green spaces such as parks and nature reserves are widely recognized for their benefits in mitigating urban heat islands (UHIs), the benefit of urban golf courses is less established. This is the first study to combine remote sensing of golf courses with Morphological Spatial Pattern Analysis (MSPA) of vegetation cover. Using ArborCamTM multispectral, high-resolution airborne imagery (0.3 × 0.3 m), this study develops an approach that assesses the role of golf courses in reducing urban land surface temperature (LST) relative to other urban land-uses in Perth, Australia, and identifies factors that influence cooling. The study revealed that urban golf courses had the second lowest LST (around 31 °C) after conservation land (30 °C), compared to industrial, residential, and main road land uses, which ranged from 35 to 37 °C. They thus have a strong capacity for summer urban heat mitigation. Within the golf courses, distance to water bodies and vegetation structure are important factors contributing to cooling effects. Green spaces comprising tall trees (>10 m) and large vegetation patches have strong effects in reducing LST. This suggests that increasing the proportion of large trees, and increasing vegetation connectivity within golf courses and with other local green spaces, can decrease urban LST, thus providing benefits for urban residents. Moreover, as golf courses are useful for biodiversity conservation, planning for new golf course development should embrace the retention of native vegetation and linkages to conservation corridors.

Episparis tortuosalis (Moore, The Lepidoptera of Ceylon, L. Reeve Company, London, 1867) (Lepidoptera: Erebidae: Pangraptini) is a significant pest defoliating Chukrasia tabularis plantations in Vietnam. Since 2013 the geographic range of the pest has increased from one to nine provinces. Field surveys in 9 provinces in 2021 showed that feeding by E. tortuosalis larvae resulted in the damage incidence ranging from 28.5 to 100% and the damage index from 0.82 to 3.66. This study illustrates the male and female morphology and genitalia of this pest from Vietnam. Further studies are recommended to help develop an integrated pest management plan for this pest.

Aims Organic carbon has been reported in deep regolithic profiles to depths of tens of metres, but the composition of the carbon compounds is unknown. Methods Residual carbon in the form of non-volatile low molecular weight compounds (LMWC) was characterised in three deep soil profiles to a depth of 19 m under farmland in south-western Australia following extraction with ethyl acetate and analysis by GC/MS. Pyrolysis and off-line thermochemolysis were used to characterise macromolecular organic carbon (MOC) to a depth of 29 m at a fourth site. Results Three compound classes occurred across the three different field locations: (1) terpenes, (2) fatty acids, amides and alcohols, and (3) plant steroids; indicating the influence of input of the past and present vegetation. Compounds related to fatty acids were the predominant residual carbon species in deep soils, and may be derived from plants and microorganisms. Biomarkers such as lignin, polysaccharides, proteins and terpenes at 0–0.1 m implied influences of vegetation, fire events and microorganisms. Pyrolysis found that polysaccharides were distributed mainly from 0 to 0.1 m, while aromatic compounds were consistently detected down to 29 m. Conclusions Carbon was stabilised in the form of aromatic compounds in deep soil, whereas other carbon sources such as cellulose, chitin, and N-containing compounds were confined to the surface soil. LMWC (Z)-docos-13-enamide and bis(6-methylheptyl) phthalate, were the main components throughout the soil profiles representing 53–81% of the LMWC, and were a greater proportion of the organic matter at depths of 18–19 m.

Invasive plant species (IPS) management in national parks is a complex problem often characterised by the involvement of various organisations with different responsibilities, legal mandates, and jurisdictions. These institutional arrangements shape the structure, function, and decision-making behaviours of organisations and influence management effectiveness. Drawing on institutional theory, this study analysed institutional arrangements and how these influenced IPS management in national parks of Vietnam. Data were collected between May and July 2017 using in-depth interviews with 39 key informants with responsibilities for IPS management at different institutional levels (national, provincial, local national parks). Results demonstrated that IPS management in Vietnam’s national parks was characterised by centralised management with overlaps and gaps in vertical institutional relationships that limited the effectiveness of horizontal relationships. These characteristics resulted in a lack of clear guiding regulations and limited resources that restricted decision making and hindered implementation at the local national park level. The study highlights the need for a common set of principles across agencies, governed by an overarching body to promote constructive relationships across the vertical and horizontal institutional dimensions of IPS management.

Zinc (Zn) biofortification can improve grain yield and nutritional quality in rice, but its effectiveness is subject to agronomic practices and other factors. In a previous study, the application of Zn to soil enhanced grain Zn in lowland rice in well-drained and waterlogged soil, whereas grain Zn in upland rice increased only in well-drained soil. This new study explores the hypothesis that the application of foliar Zn can enhance grain Zn in upland and lowland rice grown under waterlogged and well-drained conditions. Two rice varieties, CNT1 (wetland rice) and KH CMU (upland rice) were grown in containers in waterlogged or well-drained soil with three Zn treatments (no Zn, soil Zn and foliar Zn). For the soil Zn treatment, 50 kg ZnSO4 ha−1 was applied to the soil before transplanting. For the foliar treatment, 0.5% ZnSO4 (equivalent to 900 L ha−1) was applied at booting and repeated at flowering and milky growth stages. Grain yield in CNT1 was 15.9% higher in the waterlogged than in the well-drained plants, but the water regime had no effect on grain yield in KH CMU. Grain Zn concentration in CNT1 increased from 19.5% to 32.6% above the no Zn control when plants were applied with soil or foliar Zn. In KH CMU, there was an interaction between the water regime and Zn treatment. Application of foliar Zn increased grain Zn by 44.6% in well-drained and 14.7% in waterlogged soil. The results indicate strong interaction effects between variety, water regime and Zn fertilizer application on Zn biofortification in rice. Thus, the selection of rice varieties and growing conditions should be considered in order for producers to achieve desirable outcomes from high grain Zn concentrations.

Enhancing the nutrition of fruit trees and crops with chemical fertilizers is one of the most important tools to increase production and improve crop quality during the harvest stage. In East Azerbaijan, apples are grown on calcareous soils, and managing tree nutrition is a precursor to increasing fruit yield and post-harvest fruit quality. A factorial experiment was conducted in a completely randomized block design in a Red Delicious apple orchard to investigate whether the application of calcium nitrate (Ca(NO3)2) at 50, 100, and 150 g tree−1 and iron (Fe) chelate (6% Fe) at (10, 20, and 30 mL tree-1) to the soil are beneficial. The fertilizers were applied at three times during fruit development: stage of cell division in young fruit, stage of peak rate of cell expansion and starch accumulation, and stage of cell expansion and the beginning of starch decline. The addition of Ca(NO3)2 and Fe-chelate affected fruit yield and fruit traits in storage, including total carbohydrate, pH, phenol, ripening index (TSS/TA), TSS, TA, fruit firmness, and weight loss. Fertilizer application also altered the concentration of some mineral nutrients in leaves and fruits. There was an interaction between storage time × Ca× Fe on fruit firmness, total carbohydrate, TSS, pH, and TA fruit. Fertilization with Fe-chelate increased fruit Ca and leaf Fe. Overall, the combination of 50 g Ca(NO3)2 and 30 mL Fe-chelate is recommended for apple orchardists in this part of Iran.

Damage by the shoot-tip borer Hypsipyla robusta (Lepidoptera: Pyralidae) has limited the commercial cultivation of Chukrasia tabularis (Meliaceae) in many parts of the world. Recently, a number of C. tabularis families in Vietnam have shown field resistance to H. robusta. This study explores whether endophytic bacteria in C. tabularis can inhibit the development of H. robusta. Endophytic bacteria from resistant trees had strong repellent (73–97%) and antifeedant (74–84%) activity with H. robusta in laboratory trials. The most biologically active isolates were identified as Bacillus bombysepticus (4 isolates) and Bacillus velezensis (2 isolates) based on phylogenetic analysis of 16S rRNA, gyrB, pycA and rpoB. Fifteen days after releasing H. robusta larvae in a nursery trial, spray inoculation with bacterial solutions from resistant trees reduced shoot tip damage by over 60% compared with the control. Spray treatments with bacterial endophytes from susceptible trees were less effective. These findings have application to the future development of biological control of H. robusta, and the selection of resistant trees for breeding.

Fifteen fungal and three bacterial biological control agents (F-BCA and B-BCA, respectively) were isolated from the canola production areas of Western Australia to investigate their potential for controlling sclerotinia stem rot (SSR) caused by Sclerotinia sclerotiorum under in vitro and field conditions. The capacity of these isolates to inhibit mycelial growth and sclerotia formation by S. sclerotiorum was assessed in dual culture tests in Petri dishes. Using Sanger Sequencing of the ITS regions, the F-BCAs were identified as Trichoderma atroviride (four isolates), T. gamsii (three isolates), T. koningiopsis (two isolates), T. longibrachiatum (two isolates), T. paraviridescens (two isolates), T. pseudokoningii (one isolate) and T. viridescens (one isolate). Four of the seven Trichoderma species (T. koningiopsis, T. gamsii, T. atroviride and T. viridescens) are reported for the first time from Western Australia. 16S rRNA sequencing identified B-BCA1 and B-BCA2 as Serratia proteamaculans and B-BCA3 as Ochrobactrum anthropi. There were significant differences among F-BCAs (P≤0.001) in their effect on radial mycelial growth (40–60% inhibition) and sclerotia formation (65–100% inhibition). Two isolates of T. atroviride (F-BCA12 and F-BCA15) completely blocked sclerotial formation of the pathogen on Potato dextrose agar + 10 ppm/L Aureomycin (PDAA). Incubation of sclerotia in soil inoculated with F-BCA indicated that sclerotia were colonized by the conidia of each F-BCA, and all sclerotia in the presence of F-BCAs failed to germinate on PDAA. The B-BCAs reduced radial mycelial growth by 57–59% and formation of sclerotia by 89–95%. Selected isolates of F-BCAs (T. koningiopsis and T. atroviride) and B-BCAs (O. anthropi and S. proteamaculans) significantly reduced disease incidence of S. sclerotiorum under glasshouse and field conditions. Field efficacy of tested BCAs was similar or better than the commercial fungicide Prosaro®.

Aims This study identifies the contribution of leaf matter from individual plant species on water repellency with a focus on the composition of organic compounds and the role of heat in releasing these compounds to soil. Methods Leaf powder from four plant species (Banksia menziesii, Eucalyptus marginata, Allocasuarina fraseriana, Xanthorrhoea preissii) was mixed with acid-washed sand (AWS) under a range of temperatures and WR measured. Plant chemical composition was characterized by extraction of leaf powder and GC/MS analysis. Results Increasing concentrations of plant powder mixed with AWS increased WR for three species; whereas for X. preissii there was no WR at any concentration. Heating increased WR for all species over the range of 30 to 120 °C. B. menziesii had the greatest WR, which was associated with the largest diversity of fatty acids and n-alcohols and highest concentration of alkanes, whereas X. preissii with the smallest WR had only C16 alcohol and C16 fatty acids at relatively low concentration. Conclusions Physically mixing leaf powder with AWS allows the contribution of different plant species on WR to be directly examined. WR appears to be related to differences in the concentrations and diversity of n-alcohols, n-fatty acids, and high n-alkanes in the leaves. The observed temperature effects on WR provide insights into the kinetics of release and dispersal of organic compounds from interstitial material.