A Comparative Analysis of Yield Gaps and Water Productivity on Smallholder Farms in Ethiopia, South Africa and Tunisia

Agriculture in developing countries will have to transform and increase production by an estimated 70% in order to meet demands by 2050. Although well-managed commercial farms offer little manoeuvring space for increasing agricultural water productivity, smallholder farms usually operate at low input costs and therefore provide ample opportunities to reduce the potential yield gap through agricultural intensification. The aim of this paper is to analyse and compare yields and water productivities obtained in field and modelling experiments in Ethiopia (maize, garlic, onion), South Africa (tomato) and Tunisia (tomato, potato, wheat). Innovative agricultural practices were introduced on smallholder farms: irrigation scheduling and NPS Zn fertilization in Ethiopia; high-yielding cultivar, drip irrigation, mulching and organic amendments in South Africa; and crop water modelling in Tunisia. In general, crop yields increased up to eight times with innovative practices compared to current conventional farming practices. Crop water productivities were fairly stable within the same experiments, but increased with innovations, indicating that intensive farming can be more environmentally sustainable than conventional farming. Intensive farming systems in a resource-rich environment (high radiation levels, relatively fertile, deep and well-drained soils), combined with technology transfer and capacity building could be seen as viable strategies to secure food for smallholders and communities in African rural areas, as well as to improve water utilization in water-scarce catchments

China’s Rosewood Boom: A Cultural Fix to Capital Overaccumulation

Rosewood has become the world’s most trafficked group of endangered species, with global seizure values surpassing that of ivory, rhino horn, and big cats combined. This is almost entirely attributable to growth in demand from China over the past two decades. Since 2000, classical rosewood furniture that dates back to the Ming Dynasty has been revived as a hot cultural commodity. This article explores China’s recent rosewood renaissance, which has brought annual market sales up to nearly $26 billion. In contrast to accounts that attribute Chinese demand for endangered species to the conspicuous consumption of a rising elite, I focus on the speculative aspect of the demand. I argue that China’s rosewood boom is largely the result of speculative investment that functions as a “cultural fix” to the country’s growing problem of capital overaccumulation. As with Harvey’s spatial fix, a cultural fix pioneers new productive outlets for the accumulation of surplus value. Unlike Harvey’s spatial fix, however, a cultural fix seeks these new productive outlets in cultural realms—specifically, through the mutual convertibility of cultural and economic capital, as defined by Bourdieu. Given the oversaturation of more conventional investment avenues, Chinese investors have increasingly turned to rosewood and other culturally important endangered resources, such as ivory, rhino horn, and tiger parts, as a new outlet for the accumulation of surplus value. More than conspicuous consumption, China’s rosewood boom is the result of rampant financial speculation resulting from a cultural fix. Key Words: China, cultural capital, endangered species, overaccumulation, spatial fix.</p

Effectiveness of Panama as an intercontinental land bridge for large mammals

Habitat fragmentation is a primary driver of wildlife loss, and establishment of biological corridors is a common strategy to mitigate this problem. A flagship example is the Mesoamerican Biological Corridor (MBC), which aims to connect protected forest areas between Mexico and Panama to allow dispersal and gene flow of forest organisms. Because forests across Central America have continued to degrade, the functioning of the MBC has been questioned, but reliable estimates of species occurrence were unavailable. Large mammals are suitable indicators of forest functioning, so we assessed their conservation status across the Isthmus of Panama, the narrowest section of the MBC. We used large-scale camera-trap surveys and hierarchical multispecies occupancy models in a Bayesian framework to estimate the occupancy of 9 medium to large mammals and developed an occupancy-weighted connectivity metric to evaluate species-specific functional connectivity. White-lipped peccary (Tayassu pecari), jaguar (Panthera onca), giant anteater (Myrmecophaga tridactyla), white-tailed deer (Odocoileus virginianus), and tapir (Tapirus bairdii) had low expected occupancy along the MBC in Panama. Puma (Puma concolor), red brocket deer (Mazama temama), ocelot (Leopardus pardalis), and collared peccary (Pecari tajacu), which are more adaptable, had higher occupancy, even in areas with low forest cover near infrastructure. However, the majority of species were subject to ≥1 gap that was larger than their known dispersal distances, suggesting poor connectivity along the MBC in Panama. Based on our results, forests in Darien, Donoso–Santa Fe, and La Amistad International Park are critical for survival of large terrestrial mammals in Panama and 2 areas need restoration.</p

Temperature effects on egg and larval development rate in European smelt, Osmerus eperlanus, experiments and a 50 year hindcast

This study investigates the effect of water temperature on the development rate of eggs and larvae, the duration of the endogenous feeding period and its consequences for recruitment of smelt (Osmerus eperlanus) in Dutch lakes IJsselmeer and Markermeer. This study measured temperature-dependent egg and larval development rates as well as mortality rates from fertilization till the moment of absorption of the yolk-sac and from yolk-sac depletion onwards in temperature-controlled indoor experiments. Using multinomial modelling the authors found significant differences in development time of egg development stages under different temperature regimes. Based on historic water temperatures, the model predicted that the larval endogenous feeding period has advanced at a rate of about 2.9 days per decade in a more than 50 year period since 1961, yet there was no change in the duration of the endogenous feeding period. As zooplankton is more responsive to daylight than water temperature cues, a mismatch between the peak of the onset of exogenousfeeding of smelt and the peak of zooplankton blooms could lead to high mortality and therefore low recruitment of smelt. Such a mismatch might contribute to a decline in the smelt population in Lake IJsselmeer and Lake Markermeer. <br/

Genotypic and phenotypic differences in fresh weight partitioning of cut rose stems : implications for water loss

In vase life studies, cut flower fresh weight is often recorded, but mass distribution is not. Here, we addressed the variation in mass distribution among the different cut flower organs, and assessed its role in water relations. In the first part of the study, excised leaves, flower, and stem were exposed to desiccation. Water loss (per fresh mass) of both flower and stem was low, relatively constant over time and comparable between the three studied cultivars. Instead, water loss (per fresh mass) of leaves was initially much higher, and decreased upon desiccation due to stomatal closure. Leaves had the greatest contribution to cut flower water loss, while this contribution was different among the tested cultivars. Similar findings were obtained following evaluation of the contribution of leaves, stem, and flower to cut flower transpirational water loss under conditions where water supply was not limiting. A strong correlation between the leaf weight loss in the desiccation experiment and the length of vase life was found. Low evaporative demand during vase life evaluation increased vase life, and alleviated vase life differences between cultivars. Instead, high evaporative demand during evaluation shortened vase life, and increased the noted differences in vase life between cultivars. In the second part of the study, fresh weight partitioning was assessed within and among cut rose cultivars. Among eight cultivars, same weight flowering stems may have over 11% difference in leaf weight. In conclusion, cultivar differences in transpirational water loss between cut flowers of the same weight may be attributed to variations in both stomatal characteristics and mass partitioning to the leaves.</p

Conservation basic income : A non-market mechanism to support convivial conservation

This article advances a proposal for conservation basic income (CBI) as a novel strategy for funding biodiversity conservation that moves beyond widely promoted market-based instruments (MBIs). This CBI proposal responds to two important empirical developments. The first concerns growing discussions around cash transfer programs (CTPs) and universal basic income (UBI). These are increasingly implemented or piloted yet do not usually take into account environmental issues including biodiversity conservation. The second relates to MBIs like payments for ecosystem services (PES) and REDD+ (reduced emissions through avoided deforestation and forest degradation). In practice, these programs have not only commonly failed to halt biodiversity loss and alleviate poverty but have also largely abandoned their market-based origins, leading to calls for moving beyond market-based conservation entirely. We conclude that the time is right to integrate and transcend these existing mechanisms to develop conservation basic income as part of a broader paradigm shift towards convivial conservation that foregrounds concerns for social justice and equity.</p

An adverse outcome pathway-based approach to assess steatotic mixture effects of hepatotoxic pesticides in vitro

Exposure to complex chemical mixtures requires a tiered strategy for efficient mixture risk assessment. As a part of the EuroMix project we developed an adverse outcome pathway (AOP)-based assay toolbox to investigate the combined effects of the liver steatosis-inducing compounds imazalil, thiacloprid, and clothianidin in human HepaRG hepatocarcinoma cells. Compound-specific relative potency factors were determined using a benchmark dose approach. Equipotent mixtures were tested for nuclear receptor activation, gene and protein expression, and triglyceride accumulation, according to the molecular initiating events and key events proposed in the steatosis AOP. All three compounds affected the activity of nuclear receptors, but not key genes/proteins as proposed. Triglyceride accumulation was observed with three different methods. Mixture effects were in agreement with the assumption of dose additivity for all the combinations and endpoints tested. Compound-specific RPFs remained similar over the different endpoints studied downstream the AOP. Therefore, it might be possible to reduce testing to a smaller battery of key tests. The results demonstrate the suitability of our in vitro assay toolbox, integrated within an AOP framework and combined with the RPF approach, for the analysis of steatotic effects of chemical mixtures. However, mRNA results suggest that the steatosis AOP still needs improvement.</p

Impacts of agricultural industrial agglomeration on China's agricultural energy efficiency : A spatial econometrics analysis

The rapid development of traditional agriculture in China was achieved at the expense of high energy consumption and investments. However, the global green development trend made it necessary for the country to transform its agricultural energy utilization. Energy efficiency changes are affected by many factors, particularly industrial agglomeration. In recent years, the Chinese government has introduced a series of policies, including setting major producing regions for grains and advantageous regions for characteristic agricultural product. These have caused significant changes to the spatial layout of the agriculture industry. However, there is still a lack of research on the impact of these changes on agricultural energy efficiency (AEE). In this study, panel data of 30 Chinese provinces from 2000 to 2016 were entered into stochastic frontier models to measure the country's AEE at the provincial level. A series of spatial econometric models were also used to analyze the impact of agricultural industrial agglomeration on China's AEE. The results indicated that the country's AEE exhibited obvious spatial gradients and correlations. After controlling the impacts of spatial correlation and other factors in the models, agricultural industrial agglomeration was found to have an overall positive impact on China's AEE. In the future, policies should be formulated to increase AEE by establishing agricultural functional areas, strengthening the innovation and sharing of green development technologies at the farm level, and promoting the optimization of energy structures in agricultural and rural areas.</p

Predation risk shapes the degree of placentation in natural populations of live-bearing fish

The placenta is a complex life-history trait that is ubiquitous across the tree of life. Theory proposes that the placenta evolves in response to high performance-demanding conditions by shifting maternal investment from pre- to post-fertilisation, thereby reducing a female’s reproductive burden during pregnancy. We test this hypothesis by studying populations of the fish species Poeciliopsis retropinna in Costa Rica. We found substantial variation in the degree of placentation among natural populations associated with predation risk: females from high predation populations had significantly higher degrees of placentation compared to low predation females, while number, size and quality of offspring at birth remained unaffected. Moreover, a higher degree of placentation correlated with a lower reproductive burden and hence likely an improved swimming performance during pregnancy. Our study advances an adaptive explanation for why the placenta evolves by arguing that an increased degree of placentation offers a selective advantage in high predation environments.</p

A systems approach to understand microplastic occurrence and variability in Dutch riverine surface waters

Assessment methods on data quality and environmental variability are lacking for microplastics (MP). Here we assess occurrence and variability of MP number concentrations in two Dutch rivers. Strict QA/QC procedures were applied to identify MP using Fourier-transform infrared (FTIR) microscopy followed by state of the art automated image analysis. For a series of randomly selected, yet ever smaller subareas of filters, we assessed how accurately MP numbers and polymer types are represented during partial filter analysis. Levels of uncertainty were acceptable when analysing 50% of a filter during chemical mapping, and when identifying at least a subset of 50 individual particles with attenuated total reflection (ATR)-FTIR. Applying these guidelines, MP number concentrations between 67 and 11532 MP m−3 were detected in Dutch riverine surface waters. Spatial differences caused MP number concentrations to vary by two orders of magnitude. Temporal differences were lower and induced a maximum variation of one order of magnitude. In total, 26 polymer types were identified, the most common were polyethylene (23%), polypropylene (19.7%) and ethylene propylene diene monomer rubber (18.3%). The highest diversity of polymer types was found for small MPs, whereas MP larger than 1 mm was scarce and almost exclusively made of polyethylene or polypropylene. Virtually all sampling locations revealed MP number concentrations that are considerably below known effect thresholds for anticipated adverse ecological effects