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Forest Law Enforcement, Governance, and Trade agreements between the EU and countries that grow tropical timber aim to complement, alter, or generate new regulatory mechanisms that ensure the legality of timber products. These regulatory changes affect pre-existing policies and practices within timber production networks. The Indonesian-EU Voluntary Partnership Agreement was signed in 2013, and legality verification is scheduled to become mandatory for all smallholders by the end of 2017. Using grower surveys conducted in the Jepara regency of Central Java (n = 204), we generate information on who Jepara smallholders are, what timber species they are growing, and how programs that provide free and discounted seedlings contribute to STP. We use these data to understand how STP operates and how Sistem Verifikasi Legalitas Kayu (SVLK), the Indonesian method for timber legality verification, will affect STP networks and producers. We find that resource provision and oversight of source documentation increase formalization within STP. Our discussion details four policy-relevant insights for promoting STP amid continued formalization. 相似文献
995.
James Sedalia Peters David T. Damery Richard W. Wilkie 《Journal of Sustainable Forestry》2017,36(1):76-89
The article presents a material-geographic study of contemporary log home manufacturing in the Eastern Woodlands of North America. The study investigated relationships between log conversion (i.e., processing) methods and regional location. Manufacturers were grouped by their conversion methods, using hierarchical cluster analysis; and analyzed for spatial correlation, using standard deviational ellipses (SDEs). Tree species utilization, log treatment, horizontal surface type, and corner notch type were found to be spatially differentiating. These attributes were tested for their ability to predict manufacturers’ culture region using multinomial logistic regression (MLR) models. Tree species utilization was an independent variable in all of the predictive models, suggesting a correspondence between building culture and ecological regions. This is consistent with earlier research. The findings suggest that location drives tree species utilization and, thereby, building methods. Like the eco-region itself, log conversion methods vary on a north-south gradient. It is argued that construction knowledge is geo-contextual and that the replacement of scientific wood extraction with ecosystem management as the central paradigm in forestry calls for geo-contextual approaches to sustainability in the construction industry. 相似文献
996.
Ali Saber Soroosh Mortazavian David E. James Hasti Hasheminejad 《Water, air, and soil pollution》2017,228(8):312
The photo-Fenton oxidation treatment combined with a coagulation/flocculation process was investigated for removal of chemical oxygen demand (COD) from a refractory petroleum refinery wastewater. Scrap iron shavings were used as the catalyst source. A response surface methodology (RSM) with a cubic IV optimal design was employed for optimizing the treatment process. Kinetic studies showed that the proposed process could be described by a two-stage, second-order reaction model. Experiments showed that precipitation of iron ions can be utilized as a post-oxidation coagulation stage to improve the overall treatment efficiency. More than 96.9% of the COD removal was achieved under optimal conditions, with a post-oxidation coagulation stage accounting for about 30% of the removal, thus confirming the collaborative role of oxidation and coagulation in the overall treatment. A low-velocity gradient of 8.0 s?1 for a short mixing time of 10 min resulted in optimum post-oxidation coagulation. Comparison of photo-Fenton oxidation to a standard Fenton reaction in the same wastewater showed more rapid COD removal for photo-Fenton, with an initial second-order rate constant of 4.0 × 10?4 L mg?1 min?1 compared to the Fenton reaction’s overall second-order rate constant of 7.0 × 10?5 L mg?1 min?1. 相似文献
997.
Xavier Harmon Christopher N. Boyer C. Owen Gwathmey James A. Larson Roland K. Roberts 《Journal of plant nutrition》2017,40(11):1547-1556
Recent research has shown that stochastic yield response functions fit data better than deterministic yield response functions; however, little research exists comparing profit-maximizing fertilizer rates for upland cotton (Gossypium hirsutum L.) using stochastic and deterministic yield response functions. The objective of this research was to determine the most appropriate yield response functional form from which to determine the profit-maximizing potassium (K) rate for cotton in Tennessee. Data were used from a nine-year K fertilizer experiment in Jackson, Tennessee. Quadratic, quadratic-plus-plateau, linear response plateau, and linear response stochastic plateau response functions were estimated to determine the yield response function that best fit the data. The linear response stochastic plateau function was the most suitable yield response function for the data. The profit-maximizing K rate ranged from 65.2 to 74.3 kg K ha?1. Misspecification of the yield response function recommended over-application of K fertilizer and decreased the producer's short-term profits. 相似文献
998.
Eugene Mazimpaka Francis Mbuza Tukei Michael Eugene N. Gatari E. M. Bukenya Okwee-Acai James 《Tropical animal health and production》2017,49(8):1645-1656
A study was conducted to characterize the cattle production systems in Nyagatare District, Eastern Province of Rwanda using pre-tested questionnaires, interviews with key informants as well as focus group discussions in a period of 2 months. The respondents were selected by multi-stage sampling at sector and cell levels. Based on the procedure of Krejcie and Morgan (Educational and Psychological Measurement 30:607–610, 1970) to determine the overall sample size, the result indicated that the majority (98.3%) of farms were privately owned by large families of five to seven members, and most farmers (53.9%) had only primary education. Most respondents (52.6%) were in the age bracket of 41–50 years and were mainly (48.3%) located within 3 km from trading centers. The farm size averaged 6.5 ± 0.8 ha and most farms (64.7%) were fenced except in Rukomo Sector (50%) where zero grazing prevailed. Natural pastures (savanna grass land) were the main feed resource; tethering (9%) and communal grazing had diminished. Napier grass was the main planted forage (93.2%), followed by Chloris guyana (3.1%) and Brachiara (1.2%). Leguminous forages were rarely (2.5%) reported. Vita-mineral and salt block supplements, hay, and crop residues were the predominant supplementary feed stuffs used except in Karangazi and Rwemiyaga Sectors where only vita-mineral block predominated. However, maize and rice brans were reported to be the main feed stuffs used in supplementary feeding of lactating cows. Most farmers (89.7%) reported shortage of water as most of the farmers trekked their cattle to the nearest valley dams (59.2%), rivers (21.1%), and a few 6% had water on farms. Indigenous cattle were predominant (67.03%) followed by cross-breeds (28.37%) and exotics (4.6%) while all farmers kept small ruminants. Natural breeding predominated (74.9%) and most farms (60.6%) had animal houses most of which were temporary (52.8%). The reported mean age at first calving (AFC) was highest (40.2 ± .33) for Ankole and the lowest (29.1 ± .50) months for exotic cattle. Calving interval was shorter in local breeds than 65.7 ± 3.0 in exotic. The mean dairy milk yield was lowest for Ankole cattle 2.4 ± .08 as compared to the exotics (10.42 ± .36) and their crosses (7.2 ± .34). The main challenges were diseases, shortage of water, feeds, and inadequate extension services. Same observation was reported by Okello (African Journal of Range and Forage Science 22(3), 2005) in Uganda. 相似文献
999.
James J. Stapleton Charles G. Summers Jeffrey P. Mitchell Timothy S. Prather 《Phytoparasitica》2010,38(1):61-69
Experiments were conducted in laboratory bioreactors and in field plots to test effects of certain cultivated members of the
grass family (Poaceae = Gramineae), including wheat (Triticum aestivum cv. Yolo), barley (Hordeum vulgare cv. UC337), oats (Avena sativa cv. Montezuma), triticale (X Triticosecale), and a sorghum-sudangrass hybrid (Sorghum bicolor x S. sudanense = “sudex”, cv. Green Grazer V) for soil disinfestation potential. Soilborne pest organisms tested for effects on survival
and activity included the phytopathogens Sclerotium rolfsii, Pythium ultimum and Meloidogyne incognita, and a variety of weed taxa. Following soil amendment, bioreactors were incubated for 7 days at ambient (23°C) or elevated,
but sublethal (38°C day/27°C night), soil heating regimens. Addition of each of the poaceous amendments to soil at 23°C resulted
in inconsistently reduced tomato root galling (49–97%) by M. incognita, or reduced recovery of S. rolfsii and P. ultimum (0–100%) fungi in soil, after 7 days’ incubation (P ≤ 0.05). When the organisms were exposed to the poaceous soil amendments at the 38o/27o temperature regimen, nematode galling and recovery of active fungi were consistently and significantly reduced by 98–100%.
These results demonstrated feasibility of soil disinfestation (“biofumigation”) by activity of poaceous amendments, further
aided by combining plant residues with soil heating (e.g. solarization). Results from three field experiments with sudex cover
crops, conducted throughout the growing season, demonstrated biocidal activity on a range of weedy plants, including Amaranthus retroflexus, Calandrinia ciliata, Cerastium arvense, Digitaria sanguinalis, Echinochloa crus-galli and Poa annua. Both shoots and roots of sudex provided allelopathic weed biomass reductions of 35–100%, and for at least 106 days after
shredding. Deleterious activity of shredded residues incorporated in soil was less persistent. These properties in poaceous
crops can be useful for soil disinfestation; however, harmful phytotoxicity to subsequent crops may also result. In order
to take full advantage of these low-input measures for controlling soilborne diseases and pests, further understanding of
their properties must be gained, and user guidelines developed. 相似文献
1000.
Ntsikane Maine James Lowenberg-DeBoer Wilhelem Thomas Nell Zerihun Gudeta Alemu 《Precision Agriculture》2010,11(5):448-463
The response of maize (Zea mays) to banded variable-rate nitrogen (N) application over a period of 3 years (2002/3–2004/5) is analyzed. The experimental
design alternated variable-rate (VR) and single-rate (SR) applications of N. The yield monitor data were spatially autocorrelated
and therefore were analyzed with spatial regression methods. The baseline spatial regression model defined in this study showed
that the VR treatment, treatment by year and treatment by management zone were statistically significant. Sensitivity tests
were applied; the first showed that VR treatment had a yield advantage when soil depth was greater than the field average
of 174 cm. The second test showed that the VR N rates applied were close to those that would maximize profit. Partial budgeting
indicates that benefits from VR vary from year to year, but in this test VR was slightly more profitable than uniform rate
application. Economic sensitivity testing indicates that farm size and the price of maize are the key factors in the profitability
of VR N. 相似文献