Challenges in developing and implementing a decision support systems (ETÇAP) in forest management planning: a case study in Honaz and Ibradı, Turkey

Decision support systems (DSSs) are indispensable tools in preparing a forest management plan for a better combination of multiple forest values. This study attempted to develop and explain a stand-based forest management DSS (Ecosystem-based multiple-use forest planning [ETÇAP]) comprising a traditional simulation, linear programming (LP), metaheuristics and geographic information system. The model consists of five submodels; traditional management approach to handle inventory data, an empirical growth and yield model, a simulation to conceptualize management actions, a LP technique to optimize resource allocation and a simulated annealing approach to directly create a spatially feasible harvest schedule. The ETÇAP model has been implemented in a comparative two case study areas; Denizli–Honaz and Akseki–Ibrad?. Both simulation and optimization models outperformed to the traditional management plan. The periodical change of growing stock, allowable cuts, carbon sequestration and water production are used as performance indicators. The results showed that more amount of wood could be harvested over time compared to traditional level of harvesting. It could be concluded that various management strategies allowed managers to stimulate more decision options for better outputs through intertemporal trade-offs of management interventions as the model provided tools to quantify forest dynamics over time and space. Challenges exist to establish the functional relationships between forest structure and values for better quantification and integration into the management plans.     

Pedotransfer functions to assess adsorbed phosphate using iron oxide content and magnetic susceptibility in an Oxisol

Adsorbed phosphate in soils can be chemically extracted; however, this process is both time‐consuming and not cost‐effective if large numbers of samples have to be analysed. Indirect assessment of adsorbed phosphate by pedotransfer functions (PTFs) can help optimize fertilizer strategies. This study aimed to evaluate the spatial variability of adsorbed phosphate (P_ads), iron oxides and magnetic susceptibility (MS) in oxisols and to calibrate PTFs to predict P_ads. A total of 308 soil samples were collected from Hapludox and Eutrudox soils formed from sandstone in Brazil. The contents of clay (196–607 g/kg), iron oxides (40–165 g/kg), MS (1.2–29 × 10^?6 m³/kg) and P_ads (327–842 mg/kg) were in the range of typical values for these highly weathered soils. This study showed that the attributes studied were spatially dependent. Geomorphic surfaces enabled understanding of spatial variability and helped to develop a more efficient sampling scheme to calibrate PTFs. Moreover, the adsorbed phosphate in these oxisols could be predicted by a PTF using iron oxides and MS as predictors. The MS attribute enabled the most accurate prediction (concordance coefficient = 0.95, root‐mean‐square error = 46 mg/kg and relative improvement in root‐mean‐square error = ?4.12) of spatial variability through PTF compared to other predictors.     

Food resources and cyprinid diet in permanent and temporary Mediterranean rivers with natural and regulated flow

This study addresses the differences in food availability, diet and feeding activity of the Iberian barbel, between permanent and temporary nonregulated rivers, and the effect of flow regulation on feeding parameters. A total of 267 adult barbels were seasonally collected in four nonregulated and regulated rivers from permanent and temporary basins, and their gut content was analysed. Locally available food sources were evaluated across sites and seasons. Barbels from the permanent nonregulated river exhibit a more variable and diversified diet in which invertebrates assumed a large importance, especially during high flows. Barbels from the temporary nonregulated river presented a more uniform diet composed of plant material and detritus, particularly in drought seasons. Flow regulation affected different flow components in both systems, but the effects on food resources and barbels' diet were similar, resulting in an intra‐annual stabilisation of resource availability and fish diet, with a higher consumption of plants and detritus. Changes in fish diet and feeding activity in both nonregulated and regulated rivers were strongly associated with the seasonal variability of streamflow components, particularly between low‐ and high‐flow periods, and with the reduction in flow variability in the case of dam regulation. Results from this study can be used to improve guidelines for flow requirement implementation.     

生物质液化油分级产物的分离和综合利用研究

以浓硫酸为催化剂,采用甲醇-甘油复合溶剂,在高温高压的条件下对竹屑、杨木、桉木和松木进行液化,并且对液化产物进行了中和、过滤和旋转蒸发等一系列分级处理,并对液化固体残渣和气体产物进行分析。主要研究了以竹屑为原料的液化油的分级产物的组成及成分,研究结果表明:竹屑经甲醇-甘油液化,产物经过分级处理得到的主要产物为杂多酚、多糖苷和乙酰丙酸甲酯。多糖苷相主要含有多糖苷和未反应的甘油及其甘油聚合物,其中多糖苷主要为六元环吡喃糖苷,约占41.81%,甘油及其聚合物占47.27%;杂多酚相主要含有乙酰丙酸酯、杂多酚和甘油等化合物,其中甘油及其聚合物占38.04%,杂多酚相物质为难溶于水的焦油相的相对分子质量大的物质,约占杂多酚相的38.41%,并且杂多酚相的相对分子质量主要集中在990左右。     

Comparative Characterization of Enzymatic Digestion from Fish and Soybean Meal from Simulated Digestive Process of Pacific Bluefin Tuna,Thunnus orientalis

The digestive process of the Pacific bluefin tuna (PBT), Thunnus orientalis, was simulated through two phases of in vitro digestion: acidic digestion with porcine pepsin, followed by alkaline digestion with pancreatic crude extract (PCE) obtained from the PBT to hydrolyze fish meal (FM) and soybean meal (SBM) as protein substrates. The crude protein from FM resulted in a lower degree of hydrolysis (73.3%) compared with SBM (79.2%). However, the resulting digested products showed that FM contained 35% more small peptides, with sizes <6.5 kDa than those from the starting material (>150 kDa). The SBM had an increase of only 1.3% in the similar peptide cut‐offs found after hydrolysis. These results suggested that FM appeared to be a better source of protein according to the amount of low‐molecular weight peptides. In addition, the proteolytic activity of PCE showed that 88.9% of its alkaline proteolytic activity corresponded to trypsin and 2.9% corresponded to chymotrypsin activity. The results shown here demonstrate that peptide sizes are important in identifying suitable protein sources for aquafeed production to reinforce the primary results obtained from the in vitro digestibility using the pH‐Stat system. These results also contribute to a better understanding of the digestibility process in aquatic organisms.     

Evaluation of the Effects of Different Stunning Methods on the Stress Responses and Meat Quality of the Amazon hybrid surubim,Pseudoplatystoma fasciatum female × Leiarius marmoratus male

Different stunning methods (carbon dioxide [CO₂] and hypothermia) used in industrial fish processing were compared with asphyxia in air, which is used in traditional fishing, to evaluate the effects of these methods on the stress responses and the meat quality of the Amazon hybrid surubim, Pseudoplatystoma fasciatum female × Leiarius marmoratus male. After the application, blood and behavioral indicators were evaluated. Following death by gill cutting, the fish were gutted, and analyses of muscle pH, rigor mortis, the exudation of the meat, and coloration were performed. Significantly higher levels of cortisol and glucose were exhibited by the fish subjected to asphyxia than by the fish stunned by either CO₂ or hypothermia. The fish subjected to asphyxia displayed decreasing muscle pH during the first 2 h after death and showed higher rates of rigor mortis after 3 h than the fish that were stunned by the other two methods. The asphyxia is a practice that exposes fish to suffering by causing an increase in stress responses, which affects meat quality. The immersion of fish in water and ice (hypothermia) for 5 min was more effective stunning method than the use of CO₂, resulting in higher loss of sensibility and greater welfare.     

Immune Responses to Vibrio anguillarum in Yellowtail Kingfish,Seriola lalandi,Fed Selenium Supplementation

Effects of dietary selenium (Se) on immune competence of yellowtail kingfish, Seriola lalandi, were investigated. The fish were fed one of the three experimental diets including a control diet without Se supplementation and two diets supplemented with Se from Se‐yeast (Selplex) at 2 and 4 mg/kg. After feeding for 6 wk, the fish were challenged by injecting Vibrio anguillarum and observed for 2 wk. Dietary Se had no effect on feed intake, feed conversion ratio, and survival over the course of 6‐wk feeding; however, it significantly increased weight gain and Se content in muscle. Following the bacterial infection, the immune‐stimulating effects of Se were observed in antibody, lysozyme, and bactericidal responses, and there was a corresponding increase in survival and hematocrit by Se. Under infectious condition, antioxidant capacity of fish as measured in terms of resistance of red blood cells to peroxidation and glutathione peroxidase activity also increased by supplementation of Se. Liver necrosis and kidney melano‐macrophages were only seen in surviving fish fed the control diet after the challenge. Furthermore, there was evidence of myopathy in fish fed the diet without Se supplementation. This study suggests that Se, supplemented at 2 or 4 mg/kg, can improve growth and health of yellowtail kingfish.     

Early resynchronization protocols for goats: Progestogens can be used prior to an early pregnancy diagnosis without affecting corpus luteum functionality

This study aimed to evaluate the exogenous progesterone (P4) effect on the luteal function from Day 16 to Day 21 of the oestrous cycle in inseminated goats with unknown pregnancy status. A total of 54 does passed through a short progestin-based synchronization protocol and, on Day 16 of the following oestrous cycle, 27 does received a new P4 device which was retained until Day 21. Blood samples were collected daily from all does during this period, as well as on Day 24. Pregnancy diagnoses were performed on Day 30. Serum P4 values from 26 animals (G_NPSP: Group of non-pregnant does with second sponge: n = 8; G_NPNSP: Group of non-pregnant does without second sponge: n = 6; G_PSP: Group of pregnant does with second sponge: n = 5; G_PNSP: Group of pregnant does without second sponge: n = 7) were determined by radioimmunoassay commercial kits. No P4 differences were found between groups (G_NPSP: 3.1 ± 2.8; 1.7 ± 1.8; 0.4 ± 1.0; and 0.0 ± 0.0 vs. G_NPNSP: 4.4 ± 1.8; 3.0 ± 2.2; 0.8 ± 0.8; and 0.0 ± 0.0 or G_PSP: 4.2 ± 1.0; 3.4 ± 0.6; 3.3 ± 1.6; 3.2 ± 0.9; 3.6 ± 1.2; 3.5 ± 1.3; 2.7 ± 1.3 vs. G_PNSP: 4.4 ± 1.6; 3.6 ± 1.5; 3.7 ± 1.5; 3.8 ± 1.4; 3.2 ± 1.2; 3.1 ± 1.2; 3.6 ± 1.1; D16, D17, D18, D19, D20, D21, D24, respectively) or for the interaction of group and time. In conclusion, a second progestogen device had no effect on luteolysis or early pregnancy in the following oestrous cycle.     

Unravelling the relationship between a seasonal environment and the dynamics of forage growth in grazed swards

It is well reported in the scientific literature that pastures can have similar net forage accumulation when managed with contrasting structures. However, we hypothesized that the dynamics of forage accumulation in grazed swards is linked to seasonal-environmental conditions. Marandu palisadegrass (Brachiaria brizantha [Hochst. ex A. Rich.] was used as the forage species model. The experimental treatments were four grazing heights (10, 20, 30 and 40 cm) allocated to experimental units according to a randomized complete block design with four replicates and evaluated throughout four contrasting environmental seasons (summer, autumn, winter–early spring and late spring). Under rainy and warm periods, greater net forage accumulation was observed in pastures maintained taller; on the contrary, during the mild and dry periods, net forage accumulation rate reduced as grazing height increased. Such patterns of responses were related to compensations between tiller population density and tissues flows during summer and late spring and the reduced capacity of taller canopies to compensate lower population with greater growth rates during autumn and winter–early spring. Grazed swards changed their patterns of forage growth as they transitioned from favourable to more abiotic stressful conditions, suggesting that seasonal adjustments in grazing intensities are necessary in order to maximize forage production.