Multi-elemental consumer-driven nutrient cycling when predators feed on different prey

Predators play a fundamental role in cycling nutrients through ecosystems, by altering the amount and compositions of waste products and uneaten prey parts available to decomposers. Different prey can vary in their elemental content and the deposition of elements in predator waste can vary depending on which elements are preferentially retained versus eliminated as waste products. We tested how feeding on different prey (caterpillars, cockroaches, crickets, and flies) affected the concentrations of 23 elements in excreta deposited by wolf spider across 2 seasons (spring versus fall). Spider excreta had lower concentrations of carbon and higher concentrations of many other elements (Al, B, Ba, K, Li, P, S, Si, and Sr) compared to prey remains and whole prey carcasses. In addition, elemental concentrations in unconsumed whole prey carcasses and prey remains varied between prey species, while spider excreta had the lowest variation among prey species. Finally, the concentrations of elements deposited differed between seasons, with wolf spiders excreting greater concentrations of Fe, Mg, Mn, Mo, S, and V in the fall. However, in the spring, spiders excreted higher concentrations of Al, B, Ba, Ca, Cd, Cu, K, P, Na, Si, Sr, and Zn. These results highlight that prey identity and environmental variation can determine the role that predators play in regulating the cycling of many elements. A better understanding of these convoluted nutritional interactions is critical to disentangle specific consumer-driven effects on ecosystem function.

A holistic framework integrating plant-microbe-mineral regulation of soil bioavailable nitrogen

Soil organic nitrogen (N) is a critical resource for plants and microbes, but the processes that govern its cycle are not well-described. To promote a holistic understanding of soil N dynamics, we need an integrated model that links soil organic matter (SOM) cycling to bioavailable N in both unmanaged and managed landscapes, including agroecosystems. We present a framework that unifies recent conceptual advances in our understanding of three critical steps in bioavailable N cycling: organic N (ON) depolymerization and solubilization; bioavailable N sorption and desorption on mineral surfaces; and microbial ON turnover including assimilation, mineralization, and the recycling of microbial products. Consideration of the balance between these processes provides insight into the sources, sinks, and flux rates of bioavailable N. By accounting for interactions among the biological, physical, and chemical controls over ON and its availability to plants and microbes, our conceptual model unifies complex mechanisms of ON transformation in a concrete conceptual framework that is amenable to experimental testing and translates into ideas for new management practices. This framework will allow researchers and practitioners to use common measurements of particulate organic matter (POM) and mineral-associated organic matter (MAOM) to design strategic organic N-cycle interventions that optimize ecosystem productivity and minimize environmental N loss.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s10533-021-00793-9.

From pools to flow: The PROMISE framework for new insights on soil carbon cycling in a changing world

Soils represent the largest terrestrial reservoir of organic carbon, and the balance between soil organic carbon (SOC) formation and loss will drive powerful carbon-climate feedbacks over the coming century. To date, efforts to predict SOC dynamics have rested on pool-based models, which assume classes of SOC with internally homogenous physicochemical properties. However, emerging evidence suggests that soil carbon turnover is not dominantly controlled by the chemistry of carbon inputs, but rather by restrictions on microbial access to organic matter in the spatially heterogeneous soil environment. The dynamic processes that control the physicochemical protection of carbon translate poorly to pool-based SOC models; as a result, we are challenged to mechanistically predict how environmental change will impact movement of carbon between soils and the atmosphere. Here, we propose a novel conceptual framework to explore controls on belowground carbon cycling: Probabilistic Representation of Organic Matter Interactions within the Soil Environment (PROMISE). In contrast to traditional model frameworks, PROMISE does not attempt to define carbon pools united by common thermodynamic or functional attributes. Rather, the PROMISE concept considers how SOC cycling rates are governed by the stochastic processes that influence the proximity between microbial decomposers and organic matter, with emphasis on their physical location in the soil matrix. We illustrate the applications of this framework with a new biogeochemical simulation model that traces the fate of individual carbon atoms as they interact with their environment, undergoing biochemical transformations and moving through the soil pore space. We also discuss how the PROMISE framework reshapes dialogue around issues related to SOC management in a changing world. We intend the PROMISE framework to spur the development of new hypotheses, analytical tools, and model structures across disciplines that will illuminate mechanistic controls on the flow of carbon between plant, soil, and atmospheric pools.

Soil Functional Zone Management: A Vehicle for Enhancing Production and Soil Ecosystem Services in Row-Crop Agroecosystems

There is increasing global demand for food, bioenergy feedstocks and a wide variety of bio-based products. In response, agriculture has advanced production, but is increasingly depleting soil regulating and supporting ecosystem services. New production systems have emerged, such as no-tillage, that can enhance soil services but may limit yields. Moving forward, agricultural systems must reduce trade-offs between production and soil services. Soil functional zone management (SFZM) is a novel strategy for developing sustainable production systems that attempts to integrate the benefits of conventional, intensive agriculture, and no-tillage. SFZM creates distinct functional zones within crop row and inter-row spaces. By incorporating decimeter-scale spatial and temporal heterogeneity, SFZM attempts to foster greater soil biodiversity and integrate complementary soil processes at the sub-field level. Such integration maximizes soil services by creating zones of 'active turnover', optimized for crop growth and yield (provisioning services); and adjacent zones of 'soil building', that promote soil structure development, carbon storage, and moisture regulation (regulating and supporting services). These zones allow SFZM to secure existing agricultural productivity while avoiding or minimizing trade-offs with soil ecosystem services. Moreover, the specific properties of SFZM may enable sustainable increases in provisioning services via temporal intensification (expanding the portion of the year during which harvestable crops are grown). We present a conceptual model of 'virtuous cycles', illustrating how increases in crop yields within SFZM systems could create self-reinforcing feedback processes with desirable effects, including mitigation of trade-offs between yield maximization and soil ecosystem services. Through the creation of functionally distinct but interacting zones, SFZM may provide a vehicle for optimizing the delivery of multiple goods and services in agricultural systems, allowing sustainable temporal intensification while protecting and enhancing soil functioning.

[Ectopic ureter in infancy and childhood]

Two infants, 7 children and 1 young woman have been surgically treated for ureteral ectopy in the Departments of Paediatrics and of Urology of the Medical University of Pécs over the last 15 years (1974-1989). The girl/boy ratio was 8/2. In girls, who were otherwise toilet-trained with a normal voiding pattern, constant wetting and urinary infection were the leading clinical findings. The site of ureteral drainage was the vestibule in 4 patients, the urethra in 3, the vagina in 1, the prostatic utricle in 1, and it could not be determined in 1 girl. Diagnosis was based on intravenous urography, voiding cystourethrography, ultrasonography, isotope scan, endoscopy and filling up of the bladder with a methylene blue solution. The diagnosis was more obscure when the ectopic ureter drained a poorly functioning kidney. Considering that in ectopy with duplicated system the upper pole renal segment is almost always destroyed, upper pole nephrectomy and proximal ureterectomy are advocated. In 1 neonate with esophageal atresia and tracheo-esophageal fistula ultrasonography detected the ureteral malformation. In 1 girl bilateral single ureteral ectopy was found.

[Management of drug-induced priapism]

The authors demonstrate the management of erectile impotence by using Papaverin or the combination of Papaverin-Regitin and its overdosing. The overdosing should be put in mind when using these drugs. The authors also demonstrate three types of priapisms. In according to the management of 72 cases priapism, the authors are advising the irrigation of the corpus cavernosum with Dopamin after punction.

Induced priapism and its management

The authors present the seamy side of the beneficial practice to handle erectile impotence with papaverine or with the papaverine-Regitin combination. Attention is called to danger. The various forms of priapism are defined. In connection with 72 cases of priapism the attained results and the way to stop the priapic condition are described.

Current diagnostic and therapeutic methods in the treatment of vesical tumours

Reviewing the contemporary therapy of vesical tumour, the authors point to the basic principles that govern the daily practice, the precise application of which may go a long way to improving the results. Not ignorable is the experience that one part of these tumours defies discovery by multifocal and cystoscopic examination. The fundamental tenet of tumour surgery to remove the tumour by incision into sound tissue, must be respected. A brief review is given of the main lines that promise headway in dealing with the disease.

Cutaneous ureterostomy with an introverted pediculate skin flap

Cutaneous ureterostomy with application of an introverted skin flap was performed in 9 cases over a 2-year period. The method has been developed by the authors in view of the prevalence of strictures involving the terminal ureter and the stoma after unintubated cutaneous ureterostomy in case of a normal ureteral lumen. Ureteral drainage had to be resorted to in 2 cases (necrosis of the flap in one, and allergic skin reaction in the other). The intervention was carried out with success not only when the ureteral lumen was normal, but also when it was wide, short, or relatively short.

Trigonal ureterocutaneostomy

Ureterocutaneostomy by the utilization of a trigonal section (ureteral orifice) was performed in three cases, one ureter being used in two cases, and both ureters--transuretero-ureterocutaneostomy--in the third. The surgical method is described and the results are reported in detail.

Techniques for surgical repair of vesicovaginal fistulae

The surgical therapy of vesicovaginal fistulae is discussed on the basis of a surgical material of 15 patients treated over a period of 5 years. The combined, transvesical-vaginal approach was used in 5, the transvesical approach in 3, and the vaginal approach in 3 cases. Ureterosigmoidostomy was performed in 1 case. Spontaneous healing of the fistula ensued in 3 cases. The types of surgery employed are commented upon.