Tree species that 'live slow, die older' enhance tropical peat swamp restoration : Evidence from a systematic review

Degraded tropical peatlands lack tree cover and are often subject to seasonal flooding and repeated burning. These harsh environments for tree seedlings to survive and grow are therefore challenging to revegetate. Knowledge on species performance from previous plantings represents an important evidence base to help guide future tropical peat swamp forest (TPSF) restoration efforts. We conducted a systematic review of the survival and growth of tree species planted in degraded peatlands across Southeast Asia to examine (1) species differences, (2) the impact of seedling and site treatments on survival and growth and (3) the potential use of plant functional traits to predict seedling survival and growth rates. Planted seedling monitoring data were compiled through a systematic review of journal articles, conference proceedings, reports, theses and unpublished datasets. In total, 94 study-sites were included, spanning three decades from 1988 to 2019, and including 141 indigenous peatland tree and palm species. Accounting for variable planting numbers and monitoring durations, we analysed three measures of survival and growth: (1) final survival weighted by the number of seedlings planted, (2) half-life, that is, duration until 50% mortality and (3) relative growth rates (RGR) corrected for initial planting height of seedlings. Average final survival was 62% and half-life was 33 months across all species, sites and treatments. Species differed significantly in survival and half-life. Seedling and site treatments had small effects with the strongest being higher survival of mycorrhizal fungi inoculated seedlings; lower survival, half-life and RGR when shading seedlings; and lower RGR and higher survival when fertilising seedlings. Leaf nutrient and wood density traits predicted TPSF species survival, but not half-life and RGR. RGR and half-life were negatively correlated, meaning that slower growing species survived for longer. Synthesis and applications. To advance tropical peat swamp reforestation requires expanding the number and replication of species planted and testing treatments by adopting control vs. treatment experimental designs. Species selection should involve slower growing species (e.g. Lophopetalum rigidum, Alstonia spatulata, Madhuca motleyana) that survive for longer and explore screening species based on functional traits associated with nutrient acquisition, flooding tolerance and recovery from fire.Peer reviewe

Tree species that 'live slow, die older' enhance tropical peat swamp restoration : Evidence from a systematic review

Degraded tropical peatlands lack tree cover and are often subject to seasonal flooding and repeated burning. These harsh environments for tree seedlings to survive and grow are therefore challenging to revegetate. Knowledge on species performance from previous plantings represents an important evidence base to help guide future tropical peat swamp forest (TPSF) restoration efforts. We conducted a systematic review of the survival and growth of tree species planted in degraded peatlands across Southeast Asia to examine (1) species differences, (2) the impact of seedling and site treatments on survival and growth and (3) the potential use of plant functional traits to predict seedling survival and growth rates. Planted seedling monitoring data were compiled through a systematic review of journal articles, conference proceedings, reports, theses and unpublished datasets. In total, 94 study-sites were included, spanning three decades from 1988 to 2019, and including 141 indigenous peatland tree and palm species. Accounting for variable planting numbers and monitoring durations, we analysed three measures of survival and growth: (1) final survival weighted by the number of seedlings planted, (2) half-life, that is, duration until 50% mortality and (3) relative growth rates (RGR) corrected for initial planting height of seedlings. Average final survival was 62% and half-life was 33 months across all species, sites and treatments. Species differed significantly in survival and half-life. Seedling and site treatments had small effects with the strongest being higher survival of mycorrhizal fungi inoculated seedlings; lower survival, half-life and RGR when shading seedlings; and lower RGR and higher survival when fertilising seedlings. Leaf nutrient and wood density traits predicted TPSF species survival, but not half-life and RGR. RGR and half-life were negatively correlated, meaning that slower growing species survived for longer. Synthesis and applications. To advance tropical peat swamp reforestation requires expanding the number and replication of species planted and testing treatments by adopting control vs. treatment experimental designs. Species selection should involve slower growing species (e.g. Lophopetalum rigidum, Alstonia spatulata, Madhuca motleyana) that survive for longer and explore screening species based on functional traits associated with nutrient acquisition, flooding tolerance and recovery from fire.Peer reviewe

Helminth-Associated Systemic Immune Activation and HIV Co-receptor Expression: Response to Albendazole/Praziquantel Treatment

Background: It has been hypothesized that helminth infections increase HIV susceptibility by enhancing systemic immune activation and hence contribute to elevated HIV-1 transmission in sub-Saharan Africa. Objective: To study systemic immune activation and HIV-1 co-receptor expression in relation to different helminth infections and in response to helminth treatment. Methods: HIV-negative adults with (n = 189) or without (n = 57) different helminth infections, as diagnosed by Kato-Katz, were enrolled in Mbeya, Tanzania. Blinded to helminth infection status, T cell differentiation (CD45RO, CD27),activation (HLA-DR, CD38) and CCR5 expression was determined at baseline and 3 months after Albendazole/Praziquantel treatment. Plasma cytokine levels were compared using a cytometric bead array. Results: Trichuris and Ascaris infections were linked to increased frequencies of "activated'' CD4 and/or CD8 T cells (p< 0.05),whereas Hookworm infection was associated with a trend towards decreased HLA-DR+ CD8 T cell frequencies (p = 0.222). In Trichuris infected subjects, there was a linear correlation between HLA-DR+ CD4 T cell frequencies and the cytokines IL-1 beta and IL-10 (p<0.05). Helminth treatment with Albendazole and Praziquantel significantly decreased eosinophilia for S. mansoni and Hookworm infections (p<0.005) but not for Trichuris infection and only moderately modulated T cell activation. CCR5 surface density on memory CD4 T cells was increased by 1.2-fold during Trichuris infection (p-value: 0.053) and reduced after treatment (p = 0.003). Conclusions: Increased expression of T cell activation markers was associated with Trichuris and Ascaris infections with relatively little effect of helminth treatment

Pengaruh Kompetensi, Kompleksitas Tugas dan Skeptisme Profesional terhadap Kualitas Audit pada Kantor Badan Pengawasan Keuangan dan Pembangunan Provinsi Sumatera Utara

Audit quality is not easy to define because there are many factors that affect quality. This study aims to determine the effect of competence, task complexity, and Auditor Professional Skepticism, on Audit Quality. The data used in this study is primary data by distributing questionnaires to all auditors at the BPKP Representative Office in North Sumatra Province. The population in this study were all auditors at the BPKP Representative Office in North Sumatra Province. The collection of data and information needed in this study was carried out with field research. The data used are primary data collected directly from the research subjects with a questionnaire form. Testing the effect of independent variables on the dependent variable is done by using multiple regression models. The results of this study indicate that both partially and simultaneously, competence, task complexity, and Auditor Professional Skepticism, have an effect on Audit Quality in the BPKP Representative office in North Sumatra Provinc

Optimal measurement locations for parameter estimation of non linear distributed parameter systems

A sensor placement approach for the purpose of accurately estimating unknown parameters of a distributed parameter system is discussed. The idea is to convert the sensor location problem to a classical experimental design. The technique consists of analysing the extrema values of the sensitivity coefficients derived from the system and their corresponding spatial positions. This information is used to formulate an efficient computational optimum experiment design on discrete domains. The scheme studied is verified by a numerical example regarding the chemical reaction in a tubular reactor for two possible scenarios; stable and unstable operation conditions. The resulting approach is easy to implement and good estimates for the parameters of the system are obtained. This study shows that the measurement location plays an essential role in the parameter estimation procedure