The increasing global demand for food, coupled with the impacts of climate change and environmental degradation, has shifted attention towards blue food systems. While these systems offer a potential solution to food security challenges, their sustainability is threatened by various factors, including overfishing, habitat destruction, and climate change. Recognising these challenges, the Food and Agriculture Organisation of the United Nations (FAO, UN) advocates for ensuring the sustainable contribution of aquatic food systems to global food security and nutrition, aligning with the United Nation’s Sustainable Development Goals (UN-SDGs). It was hypothesised that adoption of UN-SDGs would increase the interest of researchers in sustainability of fisheries and aquaculture. Therefore, a bibliometric analysis of the relevant literature published between 2000 and 2023 was conducted to test this hypothesis. The analysis revealed a significant rise in publications addressing climate change and sustainability after the adoption of the UN-SDGs. The countries exhibiting high vulnerability to climate change contributed disproportionately fewer publications to the database. The United States emerged as the leading contributor in terms of publication volume, while Canada’s University of British Columbia was identified as the institution with the highest number of contributing authors. The findings underscore pronounced geographical disparities in research output, with a predominance of countries from the Global North. The underlying factors contributing to these disparities are discussed. Furthermore, the study discusses the policy implications of these findings and emphasises the imperative to prioritise equitable research initiatives. Such efforts are essential to effectively support the realisation of the SDGs within the domain of blue food systems and sustainability.

The objective of this study was to assess the impact of short-term fasting and subsequent re-feeding cycles on compensatory growth performance, blood glucose levels, and digestive enzyme activity in mono-sex juvenile Nile tilapia (Oreochromis niloticus) over a 60-day period. A total of 150 juvenile Nile tilapia (Avg. wt. 9.34 ± 0.97 g) were allocated into five treatment groups: a control group (continuously fed) and four fasting groups — T1 (1‑day fasting), T2 (3‑day fasting), T3 (5‑day fasting), and T4 (7‑day fasting). Re-feeding occurred for 7 days in each group immediately following the fasting period in a recurring cycle. The average weight gain, specific growth rate, and feed efficiency ratio significantly (p < 0.05) declined starting from the T3 group. Blood glucose levels during fasting significantly decreased starting from the T2 group, but after re-feeding, they returned to levels comparable to the control group. The liver glycogen levels significantly (p ≤ 0.05) decreased during fasting and completely recovered upon re-feeding, while muscle glycogen levels did not show any significant (p ≤ 0.05) changes throughout the experimental duration. The activities of the digestive enzymes amylase and lipase significantly (p ≤ 0.05) decreased during fasting starting from T1 and T2 groups, respectively, but after re-feeding, they returned to the levels seen in the control group. In contrast, the protease enzyme levels during the fasting period initially increased up to the T2 group and subsequently returned to control levels in the T4 group. The findings of this study indicate that only the groups that experienced very short fasting periods, specifically up to the T2 group, attained body weights like the control group upon re-feeding due to compensatory growth. Therefore, this study concluded that implementing up to 3 days of fasting followed by 7 days of re-feeding in multiple cycles can serve as a strategy for minimizing input costs in tilapia farming.

The global uptake of green infrastructure in urban settings holds considerable promise for fostering both social and ecological benefits. Recognising the imperative to ensure equitable distribution of these advantages, this paper draws on the rich traditions of justice considerations within urban studies to inform research on urban greening. Focusing on three key trends — reconceptualising the ​‘urban’ category, acknowledging the role of historical processes in shaping contemporary uneven and unjust geographies, and considering power dynamics in infrastructure development — we propose five tenets for advancing justice-focused urban greening research. These tenets encourage researchers to act as knowledge brokers, practice reflexivity, recognise the complex dimensions of justice which diversity of scale might reveal, embrace uncertainty, and cultivate a ​“modest imaginary” concerning infrastructure projects.

Authors: 

Derickson, K., Walker, R., Hamann, M., Anderson, Adegun, O.B., Castillo, A. C.,Guerry, A., Keeler, B., Llewellyn, Liz, Matheney, A., Mogosetsi-Gabriel, N., Mundoli, S., Gajjar, S.P., Sitas, N., & Xie, L.P.

Fifty years ago this week, Gaura Devi, an ordinary woman from a nondescript village in India, hugged a tree, using her body as a shield to stop the tree from being cut down. Little did she know that this simple act of defiance would be a seminal moment in the history of India and the world. Or that Reni village, where she lived, would come to be recognised as the fountainhead of the Chipko environmental movement. What the foot soldiers of Chipko wanted was an acknowledgement of their Indigenous rights to access forest resources that were crucial for their survival. What they got instead was a national law and a ministry populated by a new breed of power brokers — who, in the years to come, would decide at times that habitat preservation is possible only by keeping local communities out.

Urbanisation is one of the most transformative drivers of global environmental change today, with India representing one of the fastest urbanising countries. The researchers map the urban expansion of India’s ten largest cities from 2001 to 2016, through a regression tree classification of Landsat data in Google Earth Engine. Indian cities are growing through sprawl, and simultaneously densifying through in-filling. In Delhi, Mumbai and Pune, urban growth is multinucleated, aggregating to form a larger urban region. However, the dominant pattern in most cities is mono-nucleated growth via edge-expansion. The colonial signature is visible in many cities such as Bengaluru, where due to the British colonial practice of planting trees in the cantonment, the city interior has lower urban density at the core as compared to the periphery. Much of the urban growth between 2001 – 2016 is at the expense of agriculture and fallow areas. Across all cities, urban patches have expanded and coalesced into larger units. At the same time, there is an overall loss of surface water cover within cities. Urban growth has led to fragmentation of tree cover, agriculture/​fallow and water bodies. This paper demonstrates that India’s urbanisation is leading to severe impacts on water security (because of the loss of surface water), biodiversity (because of the fragmentation of tree cover and the conversion of agriculture and fallow lands to built-up urban cover), factors which if left unaddressed will severely impact the sustainability of Indian urbanisation.

The social – ecological systems (SES) framework (Ostrom 2009, Science. 325(5939):419 – 22) typologically decomposes SES characteristics into nested, tiered constituent variables. Yet, aligning the framework’s concepts of resource system (RS) and resource unit (RU) with realities of individual case studies poses challenges if the underlying SES is not a single RS, but a mid to large-scale nested RS (NRS). Using a diagnostic approach, we describe NRSs — and the activities and networks of adjacent action situations (NAAS) containing them. An NRS includes the larger RS and multiple interlinked semi-autonomous subsidiary RSs, each of which support simultaneous, differently managed appropriation of individual RUs. We further identify NAASs operating within NRSs in two diverse empirical cases — networks of lake systems in Bengaluru, India and German wheat breeding systems — representing a lever towards understanding transformation of SESs into sustainable futures. This paper contributes towards unpacking and diagnosing complexities within mid to large-scale RSs and their governance. It provides a generalizable, rigorous approach to SES case study analyses, thereby advancing methods for synthesis in sustainability science.

Cite this article: Unnikrishnan, H., Katharina Gerullis, M., Cox, M. et al. Unpacking dynamics of diverse nested resource systems through a diagnostic approach. Sustain Sci (2023). https://​doi​.org/​1​0​.​1​0​0​7​/​s​1​1​6​2​5-022 – 01268‑y