IPB University

Luedtke J.A., Chanson J., Neam K., Hobin L., Maciel A.O., Catenazzi A., Borzée A., Hamidy A., Aowphol A., Jean A., Sosa-Bartuano Á., Fong G. A., de Silva A., Fouquet A., Angulo A., et. al.

AbstractSystematic assessments of species extinction risk at regular intervals are necessary for informing conservation action1,2. Ongoing developments in taxonomy, threatening processes and research further underscore the need for reassessment3,4. Here we report the findings of the second Global Amphibian Assessment, evaluating 8,011 species for the International Union for Conservation of Nature Red List of Threatened Species. We find that amphibians are the most threatened vertebrate class (40.7% of species are globally threatened). The updated Red List Index shows that the status of amphibians is deteriorating globally, particularly for salamanders and in the Neotropics. Disease and habitat loss drove 91% of status deteriorations between 1980 and 2004. Ongoing and projected climate change effects are now of increasing concern, driving 39% of status deteriorations since 2004, followed by habitat loss (37%). Although signs of species recoveries incentivize immediate conservation action, scaled-up investment is urgently needed to reverse the current trends.

Dicks L.V., Breeze T.D., Ngo H.T., Senapathi D., An J., Aizen M.A., Basu P., Buchori D., Galetto L., Garibaldi L.A., Gemmill-Herren B., Howlett B.G., Imperatriz-Fonseca V.L., Johnson S.D., Kovács-Hostyánszki A., et. al.

Pollinator decline has attracted global attention and substantial efforts are underway to respond through national pollinator strategies and action plans. These policy responses require clarity on what is driving pollinator decline and what risks it generates for society in different parts of the world. Using a formal expert elicitation process, we evaluated the relative regional and global importance of eight drivers of pollinator decline and ten consequent risks to human well-being. Our results indicate that global policy responses should focus on reducing pressure from changes in land cover and configuration, land management and pesticides, as these were considered very important drivers in most regions. We quantify how the importance of drivers and risks from pollinator decline, differ among regions. For example, losing access to managed pollinators was considered a serious risk only for people in North America, whereas yield instability in pollinator-dependent crops was classed as a serious or high risk in four regions but only a moderate risk in Europe and North America. Overall, perceived risks were substantially higher in the Global South. Despite extensive research on pollinator decline, our analysis reveals considerable scientific uncertainty about what this means for human society. The predominant threats to pollinators vary across locations, as do perceptions of the consequences of pollinator loss. Here, the authors use formal expert elicitation methods to identify how pollination conservation experts rank the various drivers of pollinator decline and the range of risks to humans if pollination activity is lost.

Meijaard E., Brooks T.M., Carlson K.M., Slade E.M., Garcia-Ulloa J., Gaveau D.L., Lee J.S., Santika T., Juffe-Bignoli D., Struebig M.J., Wich S.A., Ancrenaz M., Koh L.P., Zamira N., Abrams J.F., et. al.

Delivering the Sustainable Development Goals (SDGs) requires balancing demands on land between agriculture (SDG 2) and biodiversity (SDG 15). The production of vegetable oils and, in particular, palm oil, illustrates these competing demands and trade-offs. Palm oil accounts for ~40% of the current global annual demand for vegetable oil as food, animal feed and fuel (210 Mt), but planted oil palm covers less than 5–5.5% of the total global oil crop area (approximately 425 Mha) due to oil palm’s relatively high yields. Recent oil palm expansion in forested regions of Borneo, Sumatra and the Malay Peninsula, where >90% of global palm oil is produced, has led to substantial concern around oil palm’s role in deforestation. Oil palm expansion’s direct contribution to regional tropical deforestation varies widely, ranging from an estimated 3% in West Africa to 50% in Malaysian Borneo. Oil palm is also implicated in peatland draining and burning in Southeast Asia. Documented negative environmental impacts from such expansion include biodiversity declines, greenhouse gas emissions and air pollution. However, oil palm generally produces more oil per area than other oil crops, is often economically viable in sites unsuitable for most other crops and generates considerable wealth for at least some actors. Global demand for vegetable oils is projected to increase by 46% by 2050. Meeting this demand through additional expansion of oil palm versus other vegetable oil crops will lead to substantial differential effects on biodiversity, food security, climate change, land degradation and livelihoods. Our Review highlights that although substantial gaps remain in our understanding of the relationship between the environmental, socio-cultural and economic impacts of oil palm, and the scope, stringency and effectiveness of initiatives to address these, there has been little research into the impacts and trade-offs of other vegetable oil crops. Greater research attention needs to be given to investigating the impacts of palm oil production compared to alternatives for the trade-offs to be assessed at a global scale. A comprehensive overview of how oil palm expansion and production has impacted forests on an international scale.

Harvey J.A., Heinen R., Armbrecht I., Basset Y., Baxter-Gilbert J.H., Bezemer T.M., Böhm M., Bommarco R., Borges P.A., Cardoso P., Clausnitzer V., Cornelisse T., Crone E.E., Dicke M., Dijkstra K.B., et. al.

Kauffman J.B., Adame M.F., Arifanti V.B., Schile‐Beers L.M., Bernardino A.F., Bhomia R.K., Donato D.C., Feller I.C., Ferreira T.O., Jesus Garcia M.D., MacKenzie R.A., Megonigal J.P., Murdiyarso D., Simpson L., Hernández Trejo H.

Mangroves sequester large quantities of carbon (C) that become significant sources of greenhouse gases when disturbed through land-use change. Thus, they are of great value to incorporate into climate change adaptation and mitigation strategies. In response, a global network of mangrove plots was established to provide policy-relevant ecological data relating to interactions of mangrove C stocks with climatic, tidal, plant community, and geomorphic factors. Mangroves from 190 sites were sampled across five continents encompassing large biological, physical, and climatic gradients using consistent methodologies for the quantification of total ecosystem C stocks (TECS). Carbon stock data were collected along with vegetation, physical, and climatic data to explore potential predictive relationships. There was a 28-fold range in TECS (79-2,208 Mg C/ha) with a mean of 856 ± 32 Mg C/ha. Belowground C comprised an average 85% of the TECS. Mean soil depth was 216 cm, ranging from 22 to >300 cm, with 68 sites (35%) exceeding a depth of 300 cm. TECS were weakly correlated with metrics of forest structure, suggesting that aboveground forest structure alone cannot accurately predict TECS. Similarly, precipitation was not a strong predictor of TECS. Reasonable estimates of TECS were derived via multiple regression analysis using precipitation, soil depth, tree mass, and latitude (R2 = 0.54) as variables. Soil carbon to a 1 m depth averaged 44% of the TECS. Limiting analyses of soil C stocks to the top 1 m of soils result in large underestimates of TECS as well as in the greenhouse gas emissions that would arise from their conversion to other land uses. The current IPCC Tier 1 default TECS value for mangroves is 511 Mg C/ha, which is only 60% of our calculated global mean. This study improves current assessments of mangrove C stocks providing a foundation necessary for C valuation related to climate change mitigation. We estimate mangroves globally store about 11.7 Pg C: an aboveground carbon stock of 1.6 Pg C and a belowground carbon stock of 10.2 Pg C). The differences in the estimates of total ecosystem carbon stocks based on climate, salinity, forest structure, geomorphology, or geopolitical boundaries are not as much of an influence as the choice of soil depth included in the estimate. Choosing to limit soils to a 1 m depth resulted in estimates of 1 m depth resulted in global carbon stock estimates that exceeded 11.2 Pg C.

Qaim M., Sibhatu K.T., Siregar H., Grass I.

Rising global demand for vegetable oil during the last few decades has led to a drastic increase in the land area under oil palm. Especially in Southeast Asia, the oil palm boom has contributed to economic growth, but it has also spurred criticism about negative environmental and social effects. Here, we discuss palm oil production and consumption trends and review environmental, economic, and social consequences in different parts of the world. The oil palm expansion has contributed to tropical deforestation and associated losses in biodiversity and ecosystem functions. Simultaneously, it has increased incomes, generated employment, and reduced poverty among farm and nonfarm households. Around 50% of the worldwide oil palm land is managed by smallholders. Sustainability trade-offs between preserving global public environmental goods and private economic benefits need to be reduced. We discuss policy implications related to productivity growth, rainforest protection, mosaic landscapes, land property rights, sustainability certification, and smallholder inclusion, among others.

Sasmito S.D., Kuzyakov Y., Lubis A.A., Murdiyarso D., Hutley L.B., Bachri S., Friess D.A., Martius C., Borchard N.

Mangrove organic carbon is primarily stored in soils, which contain more than two-thirds of total mangrove ecosystem carbon stocks. Despite increasing recognition of the critical role of mangrove ecosystems for climate change mitigation, there is limited understanding of soil organic carbon sequestration mechanisms in undisturbed low-latitude mangroves, specifically on organic carbon burial rates and sources. This study assessed soil organic carbon burial rates, sources and stocks across an undisturbed coastal mudflat and mangrove hydrogeomorphological catena (fringe mangrove and interior mangrove) in Bintuni Bay, West Papua Province, Indonesia. 210Pb radionuclide sediment dating, and mixing model of natural stable isotope signatures (δ 13C and δ15N) and C/N ratio were used to estimate organic carbon burial rates and to quantify proportions of allochthonous (i.e., upland terrestrial forest) and autochthonous (i.e., on-site mangrove forest) organic carbon in the top 50 cm of the soil. Burial rates were in the range of 0.21–1.19 Mg C ha−1 yr−1. Compared to the fringe mangroves, organic carbon burial rates in interior mangroves were almost twice as high. Primary productivity of C3 upland forest vegetation and mangroves induced soil organic carbon burial in interior mangroves and this was consistent with the formation of the largest organic carbon stocks (179 ± 82 Mg C ha−1). By contrast, organic carbon stored in the fringe mangrove (68 ± 11 Mg C ha−1) and mudflat (62 ± 10 Mg C ha−1) soils mainly originated from upland forests (allochthonous origin). These findings clearly indicate that carbon sequestered and cycling in mangrove and terrestrial forest ecosystems are closely linked, and at least a part of carbon losses (e.g., erosion) from terrestrial forests is buried in mangrove ecosystems.

Purwiyanto A.I., Suteja Y., Trisno, Ningrum P.S., Putri W.A., Rozirwan, Agustriani F., Fauziyah, Cordova M.R., Koropitan A.F.

Microplastics are proven as heavy metals vector, but the adsorption mechanism still unclear. This study investigated the adsorption of Pb and Cu in microplastics in the Musi River and the environment effect. This study was conducted in 10 stations along the Musi River to the estuary. The polymers of microplastics were dominated by PP and followed by PE, PES, PVC, and nylon. The average concentration of Pb (0.0347 mg L-1 for water and 0.470 mg kg-1 for microplastics) was higher than Cu (0.0138 mg L-1 for water and 0.091 mg kg-1 for microplastics). The highest concentration of both metals in water and microplastics were found in the estuary. Environment parameters have different effects on the adsorption. The present study found that the adsorption processes were following the Freundlich model. The interaction metal-microplastic was physisorption. Pb and Cu will attach through weak bonds and easy to release into the aquatic ecosystem.

Grass I., Kubitza C., Krishna V.V., Corre M.D., Mußhoff O., Pütz P., Drescher J., Rembold K., Ariyanti E.S., Barnes A.D., Brinkmann N., Brose U., Brümmer B., Buchori D., Daniel R., et. al.

Land-use transitions can enhance the livelihoods of smallholder farmers but potential economic-ecological trade-offs remain poorly understood. Here, we present an interdisciplinary study of the environmental, social and economic consequences of land-use transitions in a tropical smallholder landscape on Sumatra, Indonesia. We find widespread biodiversity-profit trade-offs resulting from land-use transitions from forest and agroforestry systems to rubber and oil palm monocultures, for 26,894 aboveground and belowground species and whole-ecosystem multidiversity. Despite variation between ecosystem functions, profit gains come at the expense of ecosystem multifunctionality, indicating far-reaching ecosystem deterioration. We identify landscape compositions that can mitigate trade-offs under optimal land-use allocation but also show that intensive monocultures always lead to higher profits. These findings suggest that, to reduce losses in biodiversity and ecosystem functioning, changes in economic incentive structures through well-designed policies are urgently needed. Identifying economic and ecological trade-offs of land-use transitions is important to ensure sustainability. Here, Grass et al. find biodiversity-profit trade-offs in tropical land-use transitions in Sumatra, and show that targeted landscape planning is needed to increase land-use efficiency while ensuring socio-ecological sustainability.

Cordova M.R., Nurhati I.S., Riani E., Nurhasanah, Iswari M.Y.

Increased plastic uses during COVID-19 pandemic challenges efforts to reduce marine plastic debris. Despite recent observations of increased plastic-made personal protection equipment (PPE) waste in coastal areas, comparative data before and during the pandemic lacked. We present in situ monitoring data on riverine debris releases into Jakarta Bay, Indonesia, during COVID-19 pandemic relative to the 2016 baseline data. River debris at two river outlets - the Cilincing and Marunda Rivers, revealed a 5% increase in the abundance of debris and a 23-28% decrease in the weight of debris releases in March-April 2020 compared to March-April 2016, suggesting a compositional shift towards lighter debris. Plastics continued to dominate river debris at 46% (abundance) or 57% (weight). Unique to the pandemic, we observed an unprecedented presence of PPE (medical masks, gloves, hazard suits, face shields, raincoats) that accounted for 15-16% of the collected river debris of 780 ± 138 items (abundance) or 0.13 ± 0.02 tons (weight) daily. The observed increased plastic-made PPE in river outlets urges for improved medical waste management of domestic sources during the prolonged pandemic.