Ecological Compensation to Address Environmental Externalities: Lessons from South American Case Studies

Large development projects commonly cause damage to ecosystems, even after measures have been taken to avoid and reduce impacts on site. Governments are increasingly seeking to offset losses through ecological compensation programs to maintain overall levels of biodiversity and ecosystem services. The key to successful programs are criteria that reduce uncertainty and transaction costs while enhancing ecological equivalency. In South America, the government of Brazil, and Colombia have implemented compensation programs, and Peru has recently published broad guidelines and is developing detailed rules. Brazil emphasizes regulatory simplicity, which mitigates cost uncertainty, over ecological equivalence. Colombia has sophisticated methods for establishing ecological equivalence, but has yet to develop institutions necessary to reduce transaction costs. These experiences suggest a trade-off between rules that rigorously compensate losses with ecologically equivalent areas, and simpler approaches that have low transaction costs but may fail to ensure specific biodiversity goals. The success of Peru’s system will depend on being practical enough to implement at scale and rigorous enough to deliver environmental benefits. We describe a series of mutually compatible recommendations to balance both needs. Ecological compensation is still a nascent effort in the neotropics and policy adjustments will be necessary as better information on success and failure becomes available.     

Rapid deforestation and fragmentation of Chilean Temperate Forests

The temperate forests of Chile are classified a biological “hotspot” as a result of their high species diversity and high endemism. However, they are being rapidly destroyed, with significant negative impacts on biodiversity. Three land-cover maps were derived from satellite imagery acquired over 25 years (1975, 1990 and 2000), and were used to assess the patterns of deforestation and forest fragmentation in the coastal range of south-central Chile. Between 1975 and 2000, there was a reduction in natural forest area of 67% in the study area, which is equivalent to an annual forest loss rate of 4.5% per year using a compound-interest-rate formula. Forest fragmentation was associated with a decrease in forest patch size, which was associated with a rapid increase in the density of small patches (<100 ha), and a decrease in area of interior forest and in connectivity among patches. Since the 1970s, native forest loss was largely caused by an expansion of commercial plantations, which was associated with substantial changes in the spatial configuration of the native forests. By 2000, most native forest fragments were surrounded by highly connected exotic-species plantations. The assessment of forest loss and fragmentation provides a basis for future research on the impacts of forest fragmentation on the different component of biodiversity. Conservation strategies and land use planning of the study area should consider the spatial configuration pattern of native forest fragments and how this pattern changes over time and space at landscape level.     

Evaluation of a blocking ELISA using a urease conjugate for the detection of antibodies to pseudorabies virus.

A blocking enzyme-linked immunosorbent assay (ELISA) using a urease conjugate (U-B-ELISA) was evaluated for screening sera for antibodies to pseudorabies virus under field conditions. A total of 764 serum samples were analyzed by U-B-ELISA. Of these, 264 were evaluated by both virus neutralization and U-B-ELISA, and the results were compared. U-B-ELISA showed 98.5% and 98.9% sensitivity and specificity, respectively. This test combines the sensitivity and specificity of the blocking ELISA format while allowing visual assessment of results.     

Spinal meningiomas in dogs: Description of 8 cases including a novel radiological and histopathological presentation

Clinical, imaging, and histological features of 8 canine spinal meningiomas, including a cervical cystic meningioma with imaging and intraoperative features of an arachnoid cyst, are described. All meningiomas were histologically classified and graded following the international World Health Organization human classification for tumors. Six meningiomas were located in the cervical spinal cord. Myelography showed intradural/ extramedullary lesions in 3/4 cases. Magnetic resonance imaging revealed hyperintense intradural/extramedullary masses on pre-contrast T1-weighted and T2-weighted images with homogeneous contrast enhancement in 7/8 cases. One dog had a cerebrospinal fluid-filled subarachnoid cavity dorsal to the cervical spinal cord. A spinal arachnoid cyst was diagnosed on imaging, but the histopathological study of the resected tissue revealed a grade I meningothelial cystic meningioma. There were no differences in outcome associated with tumor grade and surgical treatment (6/8). Cystic meningioma should be considered in the differential diagnosis of intraspinal cystic lesions, and biopsy is necessary for definitive diagnosis.     

Improving Yield and Quality of Processing Potato Crops Grown in the Argentinian Pampas: the Role of N,P and S and Their Impact on CO<Subscript>2</Subscript> Emissions

The area grown with processing potato crops in the Argentinian Pampas has been increasing steadily since 1995. The aim of this work was to assess the effects of N, P and S upon yield and tuber quality and their impact on CO₂ emissions assessed with the Cool Farm Tool-Potato. During the spring-summer growing seasons 2008/2009 and 2009/2010, ten fertilization experiments to individually assess N, P and S effects were carried out in the southeast region of the Argentinian Pampas. Nitrogen (four N rates), phosphorus (four P rates) and sulfur (three S rates) were applied at planting and tuber initiation; at combined rates of 0, 50, 100 and 150 kg N ha^?1, and at rates of 0, 25, 50 and 100 kg P ha^?1 and 0, 10 and 20 kg S ha^?1. N and P had a positive effect on total tuber yield, but tuber dry matter concentration (DMC) decreased at higher N rates. The fraction of marketable tubers suitable for processing into French fries increased with the addition of N, showed no variations with P fertilization, and decreased when S was applied. French fry colour, length/width (L:W) ratio and tuber defects were not affected by N, P and S fertilization. With regard to CO₂ emissions assessed with the Cool Farm Tool-Potato, results showed that the higher the N rates the higher the CO₂ emissions, but they decreased at higher yields. P and S rates did not have an impact on the CO₂ emissions, which also decreased at higher yields. Under the production system of the Pampas, N should be split between planting and tuber initiation, and intermediate P rates should be applied all at planting, in order to improve crop yield and quality and to reduce CO₂ emissions.     

Bioactive Compounds Extracted from Tomato Processing by-Products as a Source of Valuable Nutrients

Alongside paper, plastic, metal and glass, an important segment in the recycling area is represented by the wastes of different vegetal processing industries. These by-products gained interest lately, in the context of food waste prevention and growing population number. In the tomato processing industry approximately, 8.5 million tons of wastes are generated globally, each year. The present study highlights the valuable bioactive constituents as lycopene, beta-carotene, glutamic acid or aspartic acid from the by-products of tomato processing industries, which can be revalorized as incorporated nutrients in functional foods. Tomato consumption is directly associated with the prevention of different chronic diseases and carcinogenesis, however the carotenoids bioavailability is a key factor in this process. Further, fiber content together with protein content of tomato seeds and benefits of their consumption are emphasized. Value–added food products obtained by tomato peels or seeds addition are exemplified in this review (bakery, meat products, pasta and noodles, dairy and oil products as well as jams and functional ice cream), in order to embrace next prototypes that can transform vegetal by-products in functional nutrients.     

Responses of wheat to zinc sulfate fertilizer and plant growth‐promoting rhizobacteria under cadmium stress in soil

Cadmium (Cd) is a major pollutant in soils as a result of extensive use of fertilizers, mining and industrial discharges. Zinc (Zn) and certain bacterial species have been known to alleviate Cd toxicity in plants. In this study, the individual and combined effects of the application of Zn and Pseudomonas species with the aim of reducing Cd stress in wheat cultivars were investigated. Plants (durum wheat and bread wheat) were exposed to different concentrations of Cd and Zn, and either P. putida or P. fluorescens in a growth chamber. Concentrations of Zn, Cd, chlorophyll (Chl), carotenoid, hydrogen peroxide (H₂O₂), and malondialdehyde (MDA), as well as antioxidant enzyme activities were assayed. The addition of Zn in soils reduced the toxicity of Cd in durum wheat more than in bread wheat even though there was more uptake of Zn in bread wheat. Analysis of variance showed that by using Zn fertilizer and Pseudomonas species the amounts of peroxidase (POD), polyphenoloxidase (PPO), MDA, and H₂O₂ were reduced at three growth stages. Surprisingly, with increasing Zn concentration, Cd concentration in plant tissue was slightly increased, which suggests that adding Zn to soil could facilitate Cd desorption from soil particles. Application of Pseudomonas and Zn could be a promising solution to reduce detrimental effects of Cd, especially in durum wheat.     

Wood biochar produces different rates of root growth and transpiration in two maize hybrids (Zea mays L.) under drought stress

This study investigated the effects of wood-derived biochar (BC) applied at 1% to a C-poor silty-loam soil in the drought-tolerant (D24) and in the drought-sensitive (P1921) Pioneer Hi-Bred maize hybrids in pot and field trials (NE Italy). D24 had better growth than P1921 under rain-fed conditions without irrigation and soil amendment. The addition of biochar increased root growth in D24 (+38% root area) and decreases it in P1921 (?9%) at the silking stage, while the fraction of finer roots (<250 µm diam.) was reduced in D24 and increased in P1921. This led both hybrids to maintain the maximum transpiration at a lower fraction of transpirable soil water (from 82% to 45% in D24, and from 46% to 22% in P1921). There were no significant variations in plant nutrient contents, productivity and in the protein and starch contents of the grains, whereas the lipid content was reduced by biochar, particularly in P1921 (2.6% vs. 3% DW, ?13%).

We conclude that biochar can be profitably used to enhance drought tolerance in maize, possibly due to improvements in the physicochemical characteristics and the water content of treated soils, although maximum benefits are expected in drought-tolerant hybrids through increased root elongation and transpiration.