Adaptability of chickpea in northern high latitude areas—Maturity responses

Global climate warming may allow ‘warm-season’ chickpea (Cicer arietinum L.) to be better adapted to the cool, high latitude areas of the world. Chickpea has a strong indeterminacy and continued growth of vegetative tissues during the later part of the reproduction period often delays maturity in high latitude areas. This study was conducted to determine the adaptability of chickpea and evaluate the relative importance of changing environments and optimizing crop management options in affecting crop maturity. Four cultivars were grown on barley and wheat stubble, and on summerfallow using rates of 0, 28, 64, 84, and 112 kg N ha^?1 of fertilizer with and without Rhizobium inoculant at six environments in Saskatchewan, Canada, during 2004–2006. Maturity of chickpea ranged from 91 d in 2006 to 136 d in 2004. About 90% of the variation in maturity was due to environments, with the remaining variation related to cultivars, seedbed conditions, and soil fertility. The cultivars ‘Amit’ and ‘CDC-Anna’ matured 2–7 d earlier than ‘CDC-Frontier’ and ‘CDC-Xena’ averaged across diverse environments. Under cool and wet environments, chickpea grown on cereal stubble matured 7–15 d earlier than those grown on summerfallow; chickpea grown at moderate rates of N fertilizer (28–84 kg ha^?1) without Rhizobium inoculant matured 15 d earlier than the crop receiving no-N fertilizer with or without inoculation. Under dry and hot environments, only marginal differences in maturity were observed among applied treatments. Our results indicate that chickpea maturity can be advanced as many as 15 days which can help minimize the risk of crop failure due to immaturity; this is achievable through the adoption of early-maturing cultivars, use of moderate rates of N fertilizer, and selection of cereal stubble as preferential seedbed. With current genotypes of chickpea, there is still considerably high risk of adapting this ‘warm-season’ crop in northern high latitude areas because of large environmental variability, but this risk might be reduced with continued global warming.     

Citrus flavanones: what is their role in cardiovascular protection?

Flavanones, including hesperidin and naringin, are polyphenolic compounds highly and almost exclusively present in citrus. Epidemiological studies reported an inverse relationship between their intake and the risk of cardiovascular diseases. Clinical and experimental data further showed their antihypertensive, lipid-lowering, insulin-sensitizing, antioxidative, and anti-inflammatory properties, which could explain their antiatherogenic action in animal models. Although flavanones may be promising compounds that are particularly active in cardiovascular disease prevention, clinical data are still scarce and most in vitro data have been obtained under nonphysiologically relevant conditions. Moreover, the mechanisms responsible for flavanone action are not fully elucidated. Therefore, further research is needed to better evaluate and understand the protective effects of flavanones in cardiovascular diseases.     

Did land protection in Silicon Valley reduce the housing stock?

One widely asserted proposition is that land protection in a metropolitan region can contribute to a scarcity of housing by reducing the total housing stock. However, much land protection occurs on land that is less suitable for development, as slopes are too sleep or because the site is too wet. An alternate hypothesis is that development in lands with these characteristics would likely occur at a lower density, and contribute little to housing stock. This study examines these two competing hypotheses for the southern portion of the San Francisco Bay Area, known as the Silicon Valley. We mapped conservation and urban development in the study area from World War II to the present. We created a counterfactual map, using a regression-based model to examine a “what if” proposition - what would the density of development have been in currently preserved lands if they had been developed like other topographically-similar unprotected sites on the landscape? In our study area, there are currently 790 000 housing units. If conserved lands, which total 47 000 ha, were developed there would likely only be an additional 51 000 housing units. Most conserved land is either too wet to be developed or is of steep enough slope that housing density would likely be low. Our results suggest that land protection had a relatively minor role in limiting the total housing stock of the region.     

Protected areas in climate space: What will the future bring?

Protected areas for conservation are intended to contain the environmental conditions that enable species and ecosystems to persist. The locations of such areas are fixed, but the environment within them may change, especially with climate change. To illustrate how multiple climate factors may change in relation to protection status, we used Principal Components Analysis to construct a climate space for California based on eight climate variables assessed at an 800-m resolution. We used projections of future climate derived from a downscaled regional climate model in conjunction with the IPCC SRES A2 scenario to assess how the climate space might shift under future conditions and to identify the combinations of conditions that may no longer occur in the state (disappearing climates) or that will be new to the state (novel climates). Disappearing climates, which were generally toward cooler and/or wetter extremes of the climate space, represented only 0.5% of California’s land area but occurred disproportionately more often in conservation areas that were fully protected. Novel climates (5.8% of California) also occurred disproportionately in fully protected areas; in most cases these climates were characterized by hotter and drier combinations with more seasonal precipitation. The disproportionate occurrence of both novel and disappearing future climates in currently protected areas may create challenges to conservation of the status quo, but such areas may also be “hotspots of opportunity” for responding to the extremes of climate change.     

Environmental degradation in karst areas of Cambodia: A legacy of war?

Karst areas in Kampot Province, southwest Cambodia, have suffered relatively recent soil erosion and partial infilling of caves by the eroded sediment. This soil loss is most pronounced in localities that have been a focus of human activity, such as along pedestrian and vehicular access routes and in areas subject to vegetation clearing and agricultural activity, but it also occurs more widely across the hillslopes. In comparable karst environments elsewhere in Cambodia and neighbouring countries erosion is similarly evident in areas that have been subject to intensive human use, but in contrast to Kampot it is absent from the broader landscape. The soil degradation in the Kampot karst seems to require disturbance of the natural vegetation cover which stabilizes the soil cover in the other karsts, probably during the latter half of the 20th century. No major changes in deliberate land‐use at the study sites that might have triggered this erosion have been identified. However, this part of Cambodia was subject to heavy aerial bombardment between 1965 and 1973, and the karst hills and their caves were a particular focus of military activity. This bombing in turn facilitated ascent of the genocidal Khmer Rouge regime which drove virtually the entire population into a subsistence rural existence, and then further armed conflict prior to that regime's overthrow, both of which are likely to have generated additional environmental damage. Copyright © 2010 John Wiley & Sons, Ltd.     

Will climate change reduce the efficacy of protected areas for amphibian conservation in Italy?

Amphibians are an important and imperiled component of biodiversity. In this study we analyze the efficacy of Italian reserve network for protecting multiple amphibian species in a climate change scenario, considering both nationally designated areas and Natura 2000 sites. Our approach is based on ensemble niche modeling estimate of potential range shift under two carbon emission scenarios (A1FI and B1) and two dispersal assumptions. The predicted distributions were used to perform gap and irreplaceability analyses. Our findings show that the current Italian reserve network incompletely represents current amphibian diversity and its geographic pattern. The combination of the nationally designated protected areas and the Natura 2000 sites improves current representation of amphibians, but conservation targets based on geographic range extent are achieved for only 40% of species. Under the future scenarios, Natura 2000 sites become a crucial component of the protected areas system. Nonetheless, we predict that climate change decreases for many species the amount of suitable range falling into reserves, regardless of our assumptions about dispersal. We identify some currently unprotected areas that have high irreplaceability scores for species conservation and that maintain their importance under all the future scenarios we considered. We recommend designation of new reserves in these areas to help guarantee long-term amphibian conservation.     

Critical phosphorus concentrations for subterranean clover in the high rainfall areas of South‐Western Australia

Abstract

The relationship between yield and phosphorus (P) concentration of dried subterranean clover (Trifolium subterraneum) herbage has been measured in many long‐term field experiments in the greater than 800 mm annual average rainfall areas of south‐western Australia. In the experiments, seven levels of different P fertilizers (single superphosphate, rock phosphates, partially acidulated rock phosphates) were applied to the surface, either annually, or once only to new plots in different years. Yields and P concentration in dried herbage were measured whenever possible in each growing season (April to November near the south coast, May to October near the west coast) for several successive years. Critical P, the P concentration in dried herbage related to 90% of the maximum yield, was calculated. At each harvest, critical P was similar for different fertilizers. However, critical P was different when measured for samples collected at about the same time in different years at the same site or different sites, and it consistently decreased with increasing maturity of clover. Mean critical P (%) with standard errors and the number of observations in parenthesis were: April, 0.63 (0.01, 2); May, 0.56 (0.01, 2); June, 0.49 (0.04, 25); July, 0.44 (0.06, 37); August, 0.34 (0.05, 71); September, 0.32 (0.06, 91); October, 0.25 (0.04, 157); and November, 0.19 (0.01, 5), for a total of 390 observations.     

Geochemical transformation of soil cover in copper–molybdenum mining areas (Erdenet,Mongolia)

Purpose

The aim of the present study is to evaluate geochemical transformation of soil cover in the territory of Erdenet (Mongolia) and to assess the environmental risk associated with soil cover contamination. The objectives of the present study included: (1) the determination of heavy metals (HMs) and metalloids contents in surface horizons of background and urban soils and the assessment of geochemical transformation of the city’s soil cover; (2) the identification of elements’ associations and patterns of their spatial distribution in the soil cover of the city; (3) the assessment of environmental hazard, related to contamination of soils with complexes of HMs and metalloids.

Materials and methods

Soil–geochemical survey was conducted by the authors in the summer periods of 2010 and 2011. In total, 225 samples, including 32 backgrounds, were collected. Bulk contents of HMs and metalloids in soil samples were analyzed by mass-spectral method with inductively coupled plasma at All-Russian Research Institute of Mineral Raw Materials (Moscow) using Elan-6100 and Optima-4300 devices (Perkin Elmer, USA).

Results and discussion

Mo, Cu, and Se appeared to be the priority pollutants nearly in all land-use zones. The maximum accumulation of Mo, Cu, Se, As, Sb, and W is restricted to the industrial area where total pollution index of soils (Zc) equals 74.8. Three technogenic associations of elements, derived mainly from petrochemical features of Erdenet ore field and characterized by similar spatial distribution within the city, are identified. Environmental assessment of surface soil horizon geochemistry in Erdenet showed that 1/5 of its area has dangerous and extremely dangerous levels of soil pollution.

Conclusions

Experience of the environmental–geochemical assessment of soil cover in the impact zone of mining enterprises could be useful for other fields of the non-ferrous metals with high lithological–geochemical heterogeneity of the territory. It suggests the need of accounting for the geological diversity and specific features of metallogeny of an area. Geochemical indices local enrichment factor/local depletion factor should be calculated against the individual background values for each soil-forming rock. Such approach allows more accurate assessment of the degree of technogenic geochemical transformation of soils and the environmental hazard of pollution.

     

Do metal contamination and plant species affect microbial abundance and bacterial diversity in the rhizosphere of metallophytes growing in mining areas in a semiarid climate?

Journal of Soils and Sediments - Mining areas are low-quality habitats for macro- and microorganisms’ development, mainly due to the degradation of the soil quality by metal pollution. The...     

Bushmeat trade in the Cross–Sanaga rivers region: Evidence for the importance of protected areas

Exploitation of wildlife for meat in the tropics (‘bushmeat’) is a critical threat for biodiversity, particularly in Africa. Here, we investigate the importance of protected areas (National Parks and other forest parks) as sources for the trade by exploring patterns in pricing and condition of bushmeat carcasses. We surveyed carcass prices in a large sample of trading points (87 markets surveyed, over a 35,000 km² area) in Cameroon and Nigeria in the Cross–Sanaga region of West Africa. We assessed evidence for national parks as the source of animals traded as bushmeat. The study area included rural and urban centers (Calabar, Nigeria, and Douala, Cameroon) close to important protected areas: the Cross River National Park in Nigeria, and Korup National Park in Cameroon. Both parks host very high species diversity, including a range of endemics. Prices increased with distance from national park boundaries, particularly in Cameroon, where parks may be less depleted than in Nigeria. There was evidence that trading points closer to parks were more likely to function as wholesalers, with meat moving onto further trading points, rather than being sold to the end consumer. Carcasses were more often smoked (a treatment aimed at preservation) if they were not sold to their final consumers; smoking was also commoner at larger trading points. Prices were higher close to the road network, where opportunities for further trade were more available. We consider how wildlife harvests in and around protected areas may be managed to minimize depletion of animal populations, and if protected areas may, on the principle of marine no-take zones, be sustainable sources for regulated harvests.     

Functional properties of soils formed from biochemical ripening of dredged sediments—subsidence mitigation in delta areas

Journal of Soils and Sediments - In delta areas, dense networks of canals have been developed through time and have to be periodically dredged. Lowering the groundwater level in delta areas deepens...     

The composition of humus in permafrost-affected soils of the Bol’shezemel’skaya and Kolyma tundra areas

Tundra soils (except for the soils of barren circles) in the moderately and extremely continental tundra areas are characterized by the pronounced surface accumulation of humic substances. The humate-fulvate nature of humus is typical of the upper horizons of surface eluvial-gley soils, gley soils, and raw-humus mountainous brown soils; the C ha/C fa ratio in them varies from 0.5 to 0.91. The fulvate-humate nature of humus (C ha/C fa = 1.27–1.50) is typical of cryozems and sandy podburs. The first and the third fractions of humic substances (hs 1 and hs 3) predominate in the composition of humus. The coefficients of correlation (R) between the major parameters of soil humus and the physicochemical characteristics of tundra soils have been calculated. These coefficients between the contents of C org, C ha, C fa, C ha1, and C ha3 and the total acidity are equal to 0.73, 0.76, 0.72, 0.85, and 0.67, respectively; for the exchangeable Mg²⁺, their values are equal to 0.66, 0.88, 0.85, 0.74, and 0.90, respectively; and for the exchangeable Ca²⁺, 0.55, 0.47, 0.39, 0.41, and 0.61, respectively (p < 0.05). The composition of exchangeable cations and the total acidity specify the conditions of fractionation of humic substances in the studied soils. The differentiation of the qualitative composition of humus in the profiles of tundra soils is well pronounced and is mainly controlled by the distribution of clay and fine silt particles.     

Roads as sources of heavy metals in urban areas. The Covões catchment experiment,Coimbra, Portugal

Purpose

This work studies the implications of different traffic patterns for heavy metal and solid pollution generation processes following rainfall events with contrasting antecedent meteorological conditions, at a periurban catchment. The aim is to provide information on the pollution processes and their potential environmental impacts for urban areas.

Materials and methods

Seven campaigns were performed covering winter, spring, and summer conditions, for rainfall events with different antecedent conditions. Four types of roads were monitored: low traffic, average traffic, heavy traffic with demanding driving situations (break and turning), and heavy traffic with high vehicle speed (motorway profile). Samples were taken at the beginning, middle and end of the events to measure within event variation in concentration. Analytical standard procedures were used to quantify pH, conductivity, turbidity, total solids, volatile solids, suspended solids, volatile suspended solids and heavy metals (Cd, Cu, Pb and Zn) in the total and dissolved forms (as to infer the particulate fraction), namely copper, zinc, cadmium and lead.

Results and discussion

The collected data show a direct relation among the number of vehicles and/or the driving manoeuvres performed by them and the amount of solids and heavy metals present in the wash out overland flow collected. An important fraction of the heavy metals is washed off in the particulate form, which represents an increased problem since the road overland flow is directed to green/brown areas and for the local aquatic ecosystems. Maximum copper values recorded exceed 0.6 mh L^?1, zinc exceeds 5 mg L^?1, lead 0.1 mg L^?1 and cadmium 0.01 mg L^?1. Values are higher after long dry spells and reduce concentration throughout the rainfall events.

Conclusions

An important part of the heavy metals (with relevance for zinc and lead) are washed off in the particulate form, pollutants are typically related to the amount of traffic, and especially to the existence of driving manoeuvres. The summer events show the highest values, due to the accumulation of pollutants during the long dry spells.

     

Gradients of abundance and biomass across reserve boundaries in six Mediterranean marine protected areas: Evidence of fish spillover?

Marine protected areas (MPAs) are considered as an effective tool in marine coastal management, and considered able to enhance local fisheries through adult fish spillover. Indirect evidence of fish spillover could be obtained by horizontal gradients in fish abundance. To address this question, the existence of gradients of fish abundance and biomass across marine reserve boundaries was assessed in six Mediterranean MPAs using underwater visual censuses performed at various distances from the core of the MPA, in integral reserve (IR), to buffer zone (BZ) and fished areas. A reserve effect was evidenced with higher values of fish species richness (×1.1), abundance (×1.3), and biomass (×4.7) recorded inside MPAs compared to adjacent fished areas. Linear correlations revealed significant negative gradients in mean fish biomass in all the reserves studied after the effect of habitat had been removed, whereas negative gradients in abundance were less conspicuous. Generalized additive models suggested two main patterns of biomass gradients, with a sharp decrease at the IR-BZ boundary or at the BZ-fished area boundary. It was estimated that fish spillover beneficial to local fisheries occurred mostly at a small spatial scale (100s of metres). The existence of regular patterns of negative fish biomass gradients from within MPAs to fished areas was consistent with the hypothesis of adult fish biomass spillover processes from marine reserves and could be considered as a general pattern in this Mediterranean region.     

Do we protect biological originality in protected areas? A new index and an application to the Bonifacio Strait Natural Reserve

Changes in biodiversity may disrupt the ecological functions performed by species assemblages. Hence, we urgently need to examine the implications of biodiversity loss not only in terms of species conservation but also in terms of sustainability of ecosystem services. The ability of protected areas to maintain local species richness has been clearly demonstrated. However, preserving goods and services provided by ecosystems requires not only the conservation of species richness but also the conservation of the most ‘original’ species, i.e. the ones with the highest average rarity of their attributes which are likely to perform some unique functions in ecosystems. We proposed a new conservation of biological originality (CBO) index as well as associated randomization tests to quantify the ability of protected areas to maintain viable populations for the most original species. As an application, we used long-term fisheries data collected in the Bonifacio Strait Natural Reserve (BSNR) to determine the species which benefited from the protection reinforcement in 1999. We also estimated a set of 14 ecomorphological functional traits on the 37 fish species caught in the BSNR and we obtained a functional originality value for each species. As a result, we found that functional originality was significantly protected in the fish assemblage of the BSNR: species with the most original functional trait combinations became more abundant after 1999. Our finding suggests that protecting most original species is an insurance against functional diversity erosion in the BSNR. More generally, our new index can be used to test whether protected areas may protect preferentially the most original species and whether restorative management promotes the reestablishment of the most original species with particular habitat requirements.     

Variability of in-channel sediment storage in a river draining highly erodible areas (the Isábena,Ebro Basin)

Purpose

In-channel sediment storage is a fundamental component of a river basin’s sediment budget. Sediment remains stored until a competent flow re-suspends and transfers it downstream. The objectives of this paper are: (1) to quantify in-channel sediment storage and its spatial and temporal dynamics in the River Isábena, a mesoscale mountainous catchment draining highly erodible areas (badlands) in the south central Pyrenees (Ebro basin) and (2) to analyse changes in storage in the mainstem channel in relation to sediment yield from the main tributaries.

Materials and methods

In-channel sediment storage was measured seasonally (from winter 2011 to winter 2012) at 14 mainstem cross-sections using a re-suspension cylinder. A minimum of three locations were sampled at each section, and two levels of agitation were applied. Samples allowed determination of the amount of sediment accumulated per unit surface area at a given point in the river; estimates of the total storage in the bed of the mainstem Isábena were derived from these data. In addition, main five tributaries were monitored for discharge and suspended sediment transport.

Results and discussion

Results show an annual sedimentary cycle, with the sediment being produced in badlands during winter, transferred to the main channel during spring, stored in the river during summer and, finally, exported out of the basin by the autumn floods. Marked spatial variability was observed; sections located immediately downstream from the main tributaries (i.e. mainly Villacarli) generally held larger amounts of sediment in the bed. Runoff and sediment inputs from the tributaries were the most important factors determining sediment storage and its spatial and temporal dynamics. The overall sediment yield of the Isábena was much higher than the in-channel sediment storage, despite the large amounts stored in the channel.

Conclusions

This finding corroborates a previous published hypothesis that fine sediment in the drainage network has a mean residence time of the order of 1 year and that the basin’s delivery ratio exceeds 90 %; both of these characteristics can be related to the high connectivity between production areas (badlands) and the river network, and to the role of baseflows allowing continuous export of sediment from the catchment.     

Inversion of soil properties in rare earth mining areas (southern Jiangxi,China) based on visible–near-infrared spectroscopy

Journal of Soils and Sediments - Traditional measurement for soil properties is time-consuming and costly, while visible–near-infrared spectroscopy enables the rapid prediction of soil...