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The Zuli River is in the northwest of the Loess Plateau. As an important center of production and domestic water source, variations in the water quality of this basin and their influencing factors are important considerations for improving the river water environment. In order to identify and predict changes in the water quality of the watershed, the following water quality indicators, namely, dissolved oxygen content (DO), five-day biological oxygen demand (BOD5), ammonia nitrogen concentration (NH3-N), the high-manganese salt index (CODMn), volatile phenol concentration (VP), total phosphorus (TP), fluoride concentration (F−), and nitrite nitrogen concentration (NO3-N), were studied together with their change trends, influencing factors, and main variation cycles in the basin from 2001 to 2021. The results were as follows: (1) All the water quality indicators except for DO and F- showed an increasing trend before 2011, and DO showed an extreme, significant downward trend. There was an increase in the content of pollutants in the water caused by chemical fertilizer and aquaculture, resulting in a decrease in the DO content. (2) There was an extreme, significant upward trend in DO after 2011, while a significant downward trend was observed in the other water quality indicators except for NO3-N. (3) According to the main variation cycle of the other water quality indicators, the DO will remain in its peak period, while the other water quality indicators except for NO3-N will remain in a trough period (which began in 2021). The increase in precipitation and runoff reduced the content of pollutants in the water. Therefore, the overall water quality of the Zuli River Basin gradually improved after 2011. This may be due to (1) increased precipitation and runoff, thereby diluting the concentration of pollutants in the river, or (2) a decreased concentration of pollutants entering the river with the decrease in soil erosion.

Aleutian Islands and Alaska Peninsula residents have selectively introduced land mammals to their primarily marine based economy over the past two centuries. This paper describes these many introductions, contexts, and the longer term roles of these cattle, sheep, reindeer, and other land mammals in discrete island settings and the regional food economy based upon interviews in ten communities and comprehensive household surveys in eight of these. Caribou are indigenous and traditionally hunted in other parts of the state but are legally “invasive” in island contexts now managed by the federal government. Access to land and natural resources by Alaska Natives and rural peoples is regulated by state and federal agencies, but Aleutian residents have shaped their environment and engineered food sources to support their communities. This paper demonstrates that hardline approaches to removing invasive land mammal species will have human consequences and an integrated management policy emphasizing food security and conservation that includes reducing the density of these introduced species is most appropriate.

To assess whether and how socioeconomic factors might be influencing global freshwater finfisheries, inland fishery data reported to the FAO between 1950 and 2015 were grouped by capture and culture, country human development index, plotted, and compared. We found that while capture inland finfishes have greatly increased on a global scale, this trend is being driven almost entirely by poorly developed (Tier-3) countries which also identify only 17% of their catch. In contrast, capture finfisheries have recently plateaued in moderately-developed (Tier-2) countries which are also identifying 16% of their catch but are dominated by a single country, China. In contrast, reported capture finfisheries are declining in well-developed (Tier-1) countries which identify nearly all (78%) of their fishes. Simultaneously, aquacultural activity has been increasing rapidly in both Tier-2 and Tier-3 countries, but only slowly in Tier-1 countries; remarkably, nearly all cultured species are being identified by all tier groups. These distinctly different trends suggest that socioeconomic factors influence how countries report and conduct capture finfisheries. Reported rapid increases in capture fisheries are worrisome in poorly developed countries because they cannot be explained and thus these fisheries cannot be managed meaningfully even though they depend on them for food. Our descriptive, proof-of-concept study suggests that socioeconomic factors should be considered in future, more sophisticated efforts to understand global freshwater fisheries which might include catch reconstruction.

This research focuses on the evolution of the largest iceberg A68 and analyzes the trajectory using Sentinel-1 SAR data. The monitoring began when A68 calved Larsen C Ice shelf on 12 July 2017, and ended on 1 February 2021. A total of 47 images were analyzed and studied to ascertain the changes in the area, trajectory and the factors that might have influenced said changes. The big size of the iceberg caught the scientific community’s attention when it started moving towards South Georgia Island, a habitat of penguins and seals. The pattern of decrease and increase in the iceberg’s size was analyzed and compared with the surrounding sea ice extent to account for longitudinal stretching and shrinkage. Iceberg’s trajectory was also studied to take into account the underlying seabed and ice rises, and their implication on A68’s maneuverability, giving rise to unique motions in the coastal regime. Two subsequent calving events in the iceberg were distinctly observed in March 2019 and April 2020. Since its inception up to December 2019, its drift was fairly gradual, with the pick up in pace observed upon its entry into open waters and departure from the peninsular region. The decrease in size was also fairly gradual with only two main calving events, as mentioned above. The cold water and sea ice surrounding the iceberg potentially helped maintain a steady state. Post its sojourn into the Southern Ocean, major calving began in December 2020 and continued through January 2021. This study explores the potential of SAR remote sensing in iceberg monitoring and tracking.

There is rich biodiversity and biomass in wetlands and these areas are important in ecosystems. Assessment of the environment of wetlands is critical in the management of pivotal ecosystems. The energy ecological footprint (EEF) is an improved form of the ecological footprint method based on the theory of energy value. EEF can be a useful tool for comparing and monitoring environmental impacts. EEF was used to investigate a national coastal wetland in Taiwan; i.e., Gaomei Wetlands. We created a wetland ecosystem evaluation model to quantify the EEF, ecological safety of the GaomeiWetlands, and energy ecological carrying capacity to assess the current environmental situation of the area between 2007 and 2013. The research results provide a reference for environmental policy execution, strategy, and planning and suggestions for sustainable development of the Gaomei Wetlands. Our study showed that the per capita ecological carrying capacity of the Gaomei Wetlands experienced fluctuations during the time of the study. However, the per capita EF had substantial growth. The per capita ecological carrying capacity of the Gaomei Wetlands was influenced by the EFs of the fossil energy land, meadows, and croplands.

The replacement of fish meal and fish oil by insect-based ingredients in the formulation of marine aquafeeds can be an important step towards sustainability. To pursue this goal, the modulation of the lipid profile of black soldier fly larvae (Hermetia illucens) has received great attention. While its nutritional profile can shift with diet, the ability to modulate its lipidome is yet to be understood. The present work provides an overview of the lipid modulation of H. illucens larvae through its diet, aiming to produce a more suitable ingredient for marine aquafeeds. Marine-based substrates significantly improve the lipid profile of H. illucens larvae, namely its omega-3 fatty acids profile. An improvement of approximately 40% can be achieved using fish discards. Substantial levels of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), two essential fatty acids for marine fish and shrimp species, were recorded in H. illucens larvae fed on fish discards and coffee silverskin with Schyzochytrium sp. Unfortunately, these improvements are still deeply connected to marine-based bioresources, some still being too costly for use at an industrial scale (e.g., microalgae). New approaches using solutions from the biotechnology toolbox will be decisive to make H. illucens larvae a feasible alternative ingredient for marine aquafeeds without having to rely on marine bioresources.

Small islands are vulnerable to the synergistic effects of climate change and anthropogenic disturbances due to the fact of their small area, geographical isolation, responsive ecologies, rapidly growing and developing populations and exposure to sea level and climate change. These changes exert pressures on ecosystem services, such as the provisioning of resources, and therefore threaten the sustainability of livelihoods. We reviewed key sustainability and livelihoods literature to bring together concepts of environmental livelihood resilience and stability across temporal and spatial scales and integrated them to produce a new conceptual framework for dynamic environmental livelihood sustainability (DESL). This framework aims to facilitate the incorporation of local community perspectives into water, energy and food nexus thinking about sustainable land use to support local livelihoods. Finally, we provide insights from this case study to evaluate the effectiveness of the DESL framework in addressing gaps in existing frameworks. We suggest this framing provides a mechanism for enhancing the agency of communities to produce more cohesive and inclusive land use management plans that can lead to enhanced environmental sustainability pathways.

Cultural ecosystem services (CESs) are direct influences on human well-being and sustainable development, and they have become increasingly important in the development and progress of society. This paper reviewed 1248 papers on CESs by using VOSviewer and CiteSpace software. On this basis, we also reviewed 179 selected empirical papers related to this field, with regards to geographical locations, study objects, evaluation methods, and categories. The results show that: (1) the number of publications related to cultural services has increased year by year, and Ecosystem Services, Ecological Indicators, and Sustainability are the top three journals with the greatest amount of research published; (2) ecosystem services, benefits, management, and social–ecological systems are perceptions closely related to CES research, which are also popular topics in the field; (3) the results of a keyword detection show that the cultural landscapes, patterns, mental health services, social value, and other keywords were popular keywords used from 2005 to 2021; (4) CESs have mainly attracted the attention of many developed countries, and the cultural services in cities, oceans, and coastal areas have become the focus for researchers; (5) the recreation and ecotourism, and aesthetic values are the common categories of the CES empirical studies, while the knowledge system and the cultural diversity are the two categories with the least amount of research; (6) the evaluation methods of CESs are mostly carried out using a traditional questionnaire and interview, but mapping and modeling methods have been widely used in recent years.