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Use of inorganic fertilizers in smallholder cropping systems in Africa is often becoming inefficient due to increasing unresponsiveness to fertilizer application. A study was conducted for 2 years (four seasons) to assess the effects of biochar made from Prosopis juliflora (Sw.) DC. biomass on nutrients, fauna abundance and subsequent influence on maize planted in a nitisol. There were 12 amendments comprising: (i) biochar applied alone at a rate of 5 and 10 Mg ha−1; (ii) three fertilizer types applied separately (di-ammonium phosphate (18:46:0), urea (46:0:0) and composite NPK (23:23:0)); (iii) six fertilizer + biochar blends of the three fertilizer types and two biochar rates (0.05 and 0.1 Mg ha−1); and (iv) a control with no inputs. Treatments were replicated four times in a randomized complete block design. The amendments were applied in the first two seasons, while the last two were used to assess residual effects. At the end of the first two seasons, total C and N were higher in soils where biochar or fertilizer + biochar was applied, with more than 15.0 g C and 1.9 g N kg−1, compared to 10.4 g C and 1.0 g N kg−1 in control plots. Available P and exchangeable K were over 200% and 100% higher in biochar or fertilizer + biochar amended than control soils, respectively. Application of biochar had no effects on macrofauna such as beetles, centipedes, millipedes, termites and ants, but attracted earthworms. Soil that received 10 Mg biochar ha−1 recorded twice the number of earthworms (207 individuals m−2) compared to soil with 5 Mg biochar ha−1 (105 individuals m−2) and control (97 individuals m−2). Soils which received biochar, with or without fertilizer, had higher taxonomic richness (7.0 species) compared to soils which received DAP (2.8) or NPK (3.8). Nematodes, particularly bacterivorous groups, decreased by more than eight times with biochar application. In the first and second seasons, 5.6 Mg maize grain yield ha−1 was obtained from plots amended with biochar (without fertilizer), which was about six times higher than that harvested from unfertilised control at 0.9 Mg ha−1. Yield differences in plots where fertilizer was applied with or without biochar were not significant. Yield in the third and fourth seasons declined to 3.2 and 1.5 Mg ha−1, irrespective of fertilizer type or biochar amounts.

In the 1980s, Danish coastal waters suffered from eutrophication and several nutrient management plans have been implemented during the years to improve ecological status. This study aims at giving a holistic ecosystem perspective on 25 years of mitigation measures. We report trends of nutrient inputs and the responses to these in various chemical and biological components. Nutrient inputs from land were reduced by ~50 % for nitrogen (N) and 56 % for phosphorus (P) since 1990. These reductions resulted in significant and parallel declines in nutrient concentrations, and initiated a shift in the dominance of primary producers towards reduced phytoplankton biomass (chlorophyll a concentration) and increased cover of macroalgae in deeper waters. In the last 5 years, eelgrass meadows have also expanded towards deeper waters, in response to improving water clarity. An expected improvement of bottom water oxygen conditions has not been observed, presumably because more frequent stratification and higher water temperatures have counteracted the expected positive effects of reduced nutrient inputs. The biomass of the benthic macrofauna decreased as expected, but it was composed of a drastic decline of filter feeders paralleled by a more moderate increase of deposit feeders. This shift was most likely induced by increasing stratification. The reduced benthic filtration along with the limited eelgrass cover probably kept relatively more particles in suspension, which can explain why improvements in the Secchi depths were modest. Overall, several ecosystem components demonstrated clear signs of improvement, suggesting that at least partial recovery is attainable. On this basis, we propose a conceptual scheme for recovery of shallow coastal ecosystems following marked reductions in nutrient inputs.

Al-Kandari, M., 2024. Intertidal macrofauna biodiversity of Kuwait: An update since 2017. In: Phillips, M.R.; Al-Naemi, S., and Duarte, C.M. (eds.), Coastlines under Global Change: Proceedings from the International Coastal Symposium (ICS) 2024 (Doha, Qatar). Journal of Coastal Research, Special Issue No. 113, pp. 906-914. Charlotte (North Carolina), ISSN 0749-0208. An intertidal biodiversity survey of the marine macrofauna of Kuwait was conducted at 42 transects, from Khor Al-Subiya in the north to the border with Saudi Arabia in the south, including sites in mainland areas and eight offshore islands. These transects were sampled qualitatively and quantitatively during the late autumn and winter between 2013 and 2016. Preliminary results of this Project in 2017 recorded more than 751 macrofaunal species identified at that time. Additional surveys were conducted at Umm Al-Namel, Auha and Miscan Islands from October 2018 to October 2019. Several newly identified species of 46 taxa were new to Kuwait, including four taxa new to the Arabian Gulf and 15 taxa new to Science in Mollusca, Polychaeta, Decapoda and Isopoda, increasing the intertidal macrofauna diversity in Kuwait and the Arabian Gulf. Here, we present an update on intertidal macrofauna biodiversity collected in Kuwait. Twenty-one papers on Kuwaiti intertidal macrofauna's taxonomy, biology and ecology have been published in international refereed journals. Most of their taxonomic status has been confirmed by molecular data. Identifying the collected intertidal macrofauna is ongoing. However, the data obtained have shown the extreme diversity of the Arabian Gulf intertidal macrofauna with many misidentified taxa and new taxa, most of which still need to be described.

Plants produce and release in the surrounding soil, the so-called rhizosphere, a vast variety of secondary metabolites. Among them, flavonoids are the most studied, mainly for their role in the establishment of rhizobium–legume symbiosis; on the other hand, some studies highlight that they are also important in the plant strategies to acquire nutrients from the soil, for example, by acting on its chemistry. The scope of this review is to give a quick overview on the types and amounts of plant-released flavonoids in order to focus on their effects on soil activities that in turn can influence nutrient availability and so plant mineral nutrition; emphasis is given to the different nutrient cycles, soil enzyme, and soil bacteria activities, and their influence on soil macrofauna and roots of other plants. Finally, the possible outcome of the climate change on these processes is discussed.

Bohai Bay, a semi-enclosed bay in northern China, is an important spawning and nursery ground for marine organisms but has experienced long-term anthropogenic pressures associated with land-based pollution, coastal engineering, and aquaculture activities. Assessing the ecological status of benthic habitats is therefore essential for evaluating the effectiveness of recent management and restoration measures. Based on summer surveys conducted from 2019 to 2023, benthic macrofauna and environmental data were used to evaluate benthic ecological quality in Bohai Bay using three commonly applied indices: the Shannon-Wiener index ( H’ ), AZTI’s Marine Biotic Index (AMBI), and multivariate AMBI (M-AMBI). The three indices showed generally consistent spatial patterns and interannual trends, although differences in sensitivity were observed. H’ and M-AMBI exhibited clearer spatial gradients and higher concordance with habitat conditions, whereas AMBI produced more clustered classifications. Overall, benthic ecological quality in Bohai Bay displayed a significant improving trend during the study period. The proportion of stations classified as slightly disturbed or undisturbed increased from 81% in 2019 to 96% in 2023, while stations in good or high ecological status increased from 56% to 76%. Spatial heterogeneity remained evident, with stations showing moderate disturbance or poor status mainly associated with localized human activities such as aquaculture, anchorage, and marine engineering. Correlation analysis and redundancy analysis further indicated that benthic communities were jointly influenced by water-column and sediment conditions. Active phosphate in the water column was closely associated with broader regional gradients, whereas sediment sulfide played a key role in shaping local benthic ecological quality and community composition. These results indicate that pollution reduction and coastal management efforts have contributed to measurable improvements in benthic ecological quality in Bohai Bay, while localized human pressures continue to influence benthic habitats, and this study provides a multi-index and multivariate framework for assessing benthic ecosystem responses to human activities that supports adaptive management of Bohai Bay and other semi-enclosed coastal systems.

This study aimed to better understand nitrogen (N), phosphorus (P), and potassium (K) cycling through litterfall in smallholder cocoa agroforestry systems and to assess if these nutrient flows can be measured using standard litterbags. Annual litter production, relative mass loss, and nutrient loss rates from cocoa leaf litter were evaluated in three farms in south-western Nigeria with and without macrofauna access. Litterfall was measured fortnightly close to the base of the cocoa tree and at the edge of the tree canopies from January 2020 to December 2021. Leaf litter decomposition rates were determined over 388 days in 2 mm mesh litterbags to exclude macrofauna and in frames open to the soil surface to allow macrofauna access. Concentrations of C, N, P, and K were measured in the remaining litter at 180, 244, 314, and 388 days after incubation. Annual estimates of litterfall (10.62 Mg DM ha −1 ) did not significantly differ between the traps close to and away from the cocoa tree trunk. Nutrient cycling from litter was estimated at approximately 101 kg N, 5 kg P, and 89 kg K ha −1  year −1 . Relative litter decomposition rates ( k ) significantly differed between frames and litterbags. Macrofauna access significantly reduced the C:N ratio in the remaining litter and increased N and P loss from the litter layer by 28 and 69%, respectively. In conclusion, nutrient flows through litterfall are considerable, and N and P transfer rates to soil are likely underestimated in litterbag experiments that exclude macrofauna.

The novel concept of the review is a focus on the organisms living in the sea ice and what mechanisms they have developed for their existence. The review describes the physical environment of the sea ice and the microorganisms living there as microalgae, bacteria, virus, fungi, meio- and macrofauna where they inhabit the brine channels and exposed to low temperatures as down to −25 °C and high salinities—up to 300. Nutrients, O2, CO2, pH, light, and UV are also identified as stressors regarding the metabolism of the microorganisms. It is argued that sea ice must be recognized as an extreme environment as based on records of very high or very low concentrations or intensities of the stressors that living organisms in the ice are exposed to and able to endure. Each taxonomic group of organisms in the sea ice are dealt with in detail in terms of the explicit stressors the group is exposed to, and specifically what known mechanisms that the organisms have amended to secure existence and life. These mechanisms are known for some group of organisms as autotrophs, bacteria, meio- and macrofauna but less so for virus and fungi. The review concludes that sea ice is an extreme environment where the stressors vary significantly in both space and time, both in consort and solitary, classifying organisms living there as polyextremophiles and extremophiles. The review relates further to extraterrestrial moons covered with sea ice and these habitats and points toward sea ice on Earth for prospective studies until further technological advances.

Coastal zones include a variety of habitats and numerous biodiversity components, which provide essential ecosystem functions and services. In the wake of the escalating climate and biodiversity crises, there is an urgency for increased understanding of how biodiversity affects ecosystem functioning. The strong seasonality in high-latitude ecosystems is adding complexity to these relationships. To examine this complexity, recurrent sampling of benthic macrofauna and solute fluxes was conducted in three shallow (< 4 m) coastal soft-sediment habitats (I sandy mud, II fine sand, and III medium sand) over a year (April 2015–April 2016) in SW Finland (N 59° 50.670′, E 23° 14.963′). In addition to temperature, key benthic fauna species ( Macoma balthica , Cerastoderma glaucum , Hediste diversicolor , and Marenzelleria spp.) accounted for variability in solute fluxes at every site (27–47% of the variability explained). At the most exposed site, with medium sand, the organic matter content also apparently affected solute fluxes. These results highlight that the strength of the benthic biodiversity-ecosystem functioning relationships depends on season, macrofauna species, and environmental context.

Deep-sea polymetallic nodule mining is in the exploration phase at present with some groups proposing a move towards extraction within years 1 . Management of this industry requires evidence of the long-term effects on deep-sea ecosystems 2 , but the ability of seafloor ecosystems to recover from impacts over decadal scales is poorly understood 3 . Here we show that, four decades after a test mining experiment that removed nodules, the biological impacts in many groups of organisms are persistent, although populations of several organisms, including sediment macrofauna, mobile deposit feeders and even large-sized sessile fauna, have begun to re-establish despite persistent physical changes at the seafloor. We also reveal that areas affected by plumes from this small-scale test have limited detectable residual sedimentation impacts with some biological assemblages similar in abundance compared to control areas after 44 years. Although some aspects of the modern collector design may cause reduced physical impact compared to this test mining experiment, our results show that mining impacts in the abyssal ocean will be persistent over at least decadal timeframes and communities will remain altered in directly disturbed areas, despite some recolonization. The long-term effects seen in our study provide critical data for effective management of mining activities, if they occur, including minimizing direct impacts and setting aside an effective network of protected areas 4 , 5 . Four decades after a test mining experiment that removed nodules, the biological impacts in many groups of organisms persist, although populations of several organisms have begun to re-establish despite persistent physical changes at the seafloor.

The conversion of natural vegetation to agricultural land uses in mountainous Andean landscapes threatens an array of key ecological processes and ecosystem services (ES). In protected areas and buffer regions that provide water to cities, it is critical to understand how interactions between plants and soil communities sustain a range of ecosystem functions associated with nutrient recycling, soil structure, and erosion control. We sought to examine how land use conversion within a mountainous tropical forest landscape influences the diversity of vegetation and soil macrofauna communities, soil physicochemical properties, and hydrological regulation services. Biodiversity and a suite of key soil‐based ES were compared in five major land uses of the Cali River watershed: (1) annual cropping systems, (2) coffee plantations, (3) pastures, (4) abandoned shrubland, and (5) secondary forests. The diversity of woody and herbaceous vegetation, as well as soil macrofauna, was assessed in each land use. Soil chemical fertility and aggregate morphology were assessed via laboratory analyses and visual separation of soil aggregates based on their origin. Infiltration, runoff, and sediment production were measured using a portable rainfall simulator. We found a decrease in the diversity of woody vegetation across land uses to be associated with lower diversity of soil macrofauna. At the same time, agricultural management, annual crops in particular, supports the largest earthworm populations, likely due to increased organic inputs and low impact tillage, which appears not to diminish soil fertility and water infiltration. In contrast, the low soil fertility in pastures was associated with the lowest values of soil C, poor aggregation, and high bulk density and likely reflects overgrazing, with negative implications for water infiltration and erosion. Associations between the different sets of variables, evaluated with co‐inertia analysis, highlight the hierarchical relevance of plant cover and woody diversity on ES. The biological complexity associated with intact forest cover appears to generate “bundles” of co‐occurring ES, with this land use demonstrating the highest infiltration, and low runoff and sediment losses. Our findings demonstrate that forests and tree‐based agricultural systems may better contribute to the provision of multiple ES, including biodiversity conservation and hydrologic regulation.