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Öğe Effects of application date and rate of foliar-applied glyphosate on pine seedlings in Turkey(Northeast Forestry Univ, 2018) Çap, Mehmet Can; Eşen, DeryaGlyphosate is the herbicide most extensively used for site preparation and conifer release. It is a broad-spectrum herbicide and therefore crop safety is a critical issue. This study assessed the early effects of 14 different treatments, including no weed control, manual weed control, and 12 foliar-applied herbicide treatments at low, intermediate, high, and highest application rates and application timing on glyphosate phytotoxicity of containerized seedlings of Austrian pine (Pinus nigra J.F. Arnold.), Scots pine (P. sylvestris L.) and maritime pine (P. pinaster Aiton), conifer species widely used for afforestation and supplementary plantings in Turkish forestry. In general, Scots pine seedlings were tolerant to glyphosate compared to the other species. Glyphosate phytotoxicity varied significantly according to the time and rate of application. Seedlings were relatively tolerant to glyphosate in April whereas they were intolerant in May. The highest herbicide rate (1.2% v:v) was consistently phytotoxic to all species. Moreover, the effect of herbicide rate on seedling survival and growth varied significantly according to application date (i.e., application rate x date interaction). Seedlings appeared tolerant to glyphosate at low and intermediate rates (0.2, 0.4% v:v) between mid-spring and mid-summer, whereas they demonstrated significant sensitivity to the highest rate across all time periods. Glyphosate at the high rate (0.8% v:v) was particularly more phytotoxic when applied in May. Application of glyphosate at rates up to 0.8% could be recommended for weed control without significant pine damage in mid-spring when the needles presumably have a dense leaf epicuticular wax layer limiting herbicide penetration. Applications of 0.8 and 1.2% v:v are not recommended during May-June.Öğe Effects of different ecological and silvicultural factors on beetle catches in the Turkish fir (Abies bornmulleriana Mattf.) ecosystems(Springer Heidelberg, 2007) Yıldız, Oktay; Eşen, Derya; Akbulut, SüleymanTo study the bark beetle attacks on Turkish fir stands and to determine the principle site and stand factors influencing beetle attacks, trap log method was used in the Western Black Sea Region of Turkey. The study was carried out in ten different locations prior to flying time in February 2003. On each experimental plot, three healthy fir trees with 30-50 cm diameter and 200 m apart were cut down with a chainsaw. From each sampling tree, needles were sub-sampled for determination of specific leaf-area and macro-nutrient concentrations. In addition, on each experimental plot, crown closure, basal-area, and stand density were measured. To determine the bulk density and nutrient concentrations of the soil, samples were taken around trees on each plot. The relationship between measured stand variables, the number of beetle species and beetle populations were evaluated using correlation and stepwise multiple regression procedure. Eight different species belonging to four different families from Coleoptera were identified in examining the trap logs. Six of these eight species (Pissodes piceae Illig., Pissodes notatus Fabr., Cryphalus piceae Ratz., Pityophthorus pityographus Ratz., Xyloterus lineatus Oliv., Pityokteines curvidens Germ.) were identified as harmful beetles (HB). The other two (Thanasimus formicarius L. and Rhizophagus dispar Payk.) were identified as predator species. The analysis showed that the total number of HB increased as the site's slope and needle specific leaf area increased. However, as needle N concentrations increased, HB population decreased. Increased Ca concentration in fir needle reduced total insect attack.Öğe Effects of different Rhododendron control methods in eastern beech (Fagus orientalis Lipsky) ecosystems in the western Black Sea region of Turkey(2006) Yıldız, Oktay; Eşen, DeryaIntensive weed control and plot preparation practices have become a critical and integral part of productive beech forest management in Turkey's coastal Black Sea region (BSR). This study was conducted in an eastern beech forest of 100+ year old in the BSR to evaluate ecosystem effects of three different experimental Rhododendron ponticum understory control methods with a randomised block design, including manual grubbing, foliar and cut stump spraying with imazapyr (Arsenal) and foliar and cut stump spraying with triclopyr (Garlon). Untreated vegetation plots served as controls. Evaluation of these treatments included their effects on understory and forest floor biomass and nutrients (C, N, P, S, K, Ca and Mg) and effects on soils, including bulk density, pH, soil nutrients (C, N, P and S), exchangeable cations (K, Ca and Mg) and soil cation exchange capacity (CEC). Grubbing and imazapyr treatments had greatly reduced the amount of understory biomass 5 years after application (P = 0.002). Triclopyr treatment also had a major effect on understory vegetation control, but by 5 years later, about 10% of the rhododendron originally present on these plots had gradually re-sprouted and partially covered the plots. Five years after woody vegetation control treatments, at the 0- to 20-cm depth, treatments did not appear to affect soil bulk density, pH and CEC. For the upper 20-cm soil depth, the exchangeable soil K concentration at the 10- to 20-cm depth on triclopyr-treated plots was 33% higher than on grubbing plots, and it was twice that of imazapyr application plots. Imazapyr plots had almost 11 times more dead organic matter on the forest floor than there was on grubbing plots. Forest floor C concentrations on imazapyr plots were 26 and 14% greater than those on grubbing and triclopyr plots, respectively. Total ecosystem (forest floor + understory + soil exchangeable) Ca content was 50% higher on imazapyr plots than that on triclopyr plots, while the ecosystem K pool on imazapyr treatment plots was 27% lower than that on triclopyr plots. Herbicides can be used as an alternative for achieving some forest management objectives when other vegetation control methods are not feasible or economical. It is recommended that vegetation control not be used on steep slopes because of greater risk of soil erosion. There may be benefits in encouraging slash disposal by fire after imazapyr treatments, thus removing recalcitrant understory residues left on the forest floor and releasing the essential nutrients within them. © 2006 The Authors.Öğe Effects of different site preparation methods on soil carbon and nutrient removal from Eastern beech regeneration sites in Turkey's Black Sea region(Elsevier, 2010) Yıldız, Oktay; Eşen, Derya; Karaöz, Ömer M.; Sargıncı, Murat; Toprak, Bülent; Soysal, YusufIn terms of wood production, eastern beech (Fagus orientalis Lipsky) is one of the most important Turkish tree species. The main forestry operation in the Black Sea region (BSR) is the harvesting of natural beech stands. These stands are naturally regenerated. A dense rhododendron (Rhododendron spp.) understorey prevents eastern beech (F. orientalis Lipsky) seed-tree regeneration in the Turkish BSR. Our study objective was to investigate the forest ecosystem effects of different woody vegetation control methods on forest floor organic matter (OM), soil organic carbon (SOC), soil physical and chemical properties and nutrients on beech regeneration sites in this region. In 2006, rhododendrons were cleared from treatment plots using hand labour by grubbing (GR), prescribed fire (PE), or machine preparation (MP) with a rake-equipped bulldozer. Untreated plots served as controls. The woody vegetation understorey, forest floor OM and mineral soil (0-20 cm) were sampled, and their biomass, SOC and nutrient content were estimated for each treatment. While effective in preparing sites for beech regeneration, the MP treatment resulted in highly compacted soil (mean = 1.5 g cm(-3)) compared to the other treatments (1.1 g cm(-3)). It also showed the largest ecosystem losses of C (-45%), N (-30%), and P (-55%) from the forest floor and mineral soil (0-20 cm). Furthermore, the MP treatment induced large ecosystem losses of soil K (-72%) and Ca (-58%). Both the GR and PF treatments increased soil pH and cation exchange capacity (CEC) relative to the controls, while their ecosystem C (-25%) and N (-22%) losses were moderate. In conclusion, the MP site preparation method removes more OM and soil nutrients, resulting in a lower soil CEC capacity compared to the other rhododendron control practices, including prescribed fire. Using heavy machinery during site preparation compacts the soil, increasing soil density to a level that may restrict plant growth. In contrast, grubbing and prescribed fire increase the soil pH and plant nutrient availability without compacting the soil. Therefore, these two methods should be promoted as effective and sustainable rhododendron control techniques for long-term productivity of eastern beech forests. (C) Elsevier B.V. All rights reserved.Öğe Effects of forest fire on soil nutrients in Turkish pine (Pinus brutia, Ten) Ecosystems(Triveni Enterprises, 2010) Yıldız, Oktay; Eşen, Derya; Sargıncı, Murat; Toprak, BülentFire is a long-standing and poorly understood component of the Mediterranean forestlands in Turkey. Fire can alter plant composition, destroy biomass, alter soil physical and chemical properties and reduce soil nutrient pools. However, fire can also promote productivity of certain ecosystems by mineralizing soil nutrients and promoting fast growing nitrogen fixing plant species. Fire effects on soils and ecosystems in Turkey and Mediterranean regions are not well understood. This study, uses a retrospective space-for-time substitution to study soil macro-nutrient changes on sites which were burned at different times during the last 8 years. The study sites are in the Fethiye Forest Management Directorate in the western Mediterranean Sea region of Turkey Our samples show 40% less Soil C, and cation exchange capacity (CEC) at 0-20 cm soil depth two weeks after the fire, Soil C and CEC appear to recover to pre-fire level in one year Concentrations of Mg were significantly lower on new-bum sites, but returned to pre-fire levels in one year Total soil N concentrations one and two years after fire were 90% higher than other sites, and total P was 9 times higher on new-bum site than averages from other sites. Some implications of these results for forest managers are discussed.Öğe Effects of vegetation control on nutrient removal and Fagus orientalis, Lipsky regeneration in the western Black Sea Region of Turkey(2007) Yıldız, Oktay; Sargıncı, Murat; Eşen, Derya; Cromack, K.Dense Rhododendron ponticum (L.) understories of eastern beech (Fagus orientalis Lipsky) stands in the Black Sea Region (BSR) of Turkey create challenging forest vegetation management problems relative to beech regeneration. Rhododendron traditionally is controlled in Turkish forests with grubbing and bulldozing. The effects of these practices on nutrient removal and natural beech regeneration have not been quantitatively studied. Two woody vegetation control treatments (bulldozing and hand-grubbing) were installed during late summer, 2002 in three mature beech stands with dense rhododendron understories in the Düzce Forest Management Directorate, in the Turkish western BSR. Aboveground biomass of each vegetation component, total aboveground vegetation biomass, nutrient concentrations, organic matter (OM) removal, and total amount of OM nutrients were determined for each woody vegetation control treatment. Soil bulk density and nutrient content, and beech seedling biomass, nutrient content, and natural regeneration also were studied. One year after treatment, the machine site preparation by bulldozing (MSP) that removed understory vegetation and attached roots, reduced mean forest floor OM content by about 84%, when compared to hand-grubbing. Mean soil C, N, K and Mg concentrations on the bulldozed sites were 36, 27, 50 and 55% less, respectively, than those on the grubbed sites. Total C and Mg amounts at the 5-10 cm soil depth were 24 and 47% lower, respectively, for mechanical site preparation (MSP) sites, when compared to grubbed sites. Overall, soil bulk density did not differ significantly between the grubbing and MSP treatments. Frequent passes on designated transects on MSP sites resulted in a significant (P < 0.01) one-third increase in bulk density of the first 20 cm soil depth, when compared to grubbed sites. No natural beech regeneration occurred on untreated control sites. Mineral soil exposure on the MSP sites increased beech seedling germination substantially. One year after treatment, the mean number of naturally regenerated seedlings for MSP sites was 2.5 times greater than for grubbed sites. Woody control treatments had significant effects upon beech seedling chemistry, with N, P, K, Ca and Mg concentrations averaging 35, 47, 12, 33 and 25% lower, respectively, for MSP sites, when compared to grubbed sites. However, mean seedling biomass and nutrient content were significantly greater (P < 0.05) on MSP sites. Long-term effects from windrowing on MSP site residues, associated topsoil and nutrients need to be evaluated. © 2007 Elsevier B.V. All rights reserved.Öğe Five-year effects of cutting and herbicide treatments on control of Rhododendron flavum Don., and macronutrient pools in eastern beech (Fagus orientalis Lipsky) forests of Turkey(Springer, 2010) Yıldız, Oktay; Eşen, Derya; Zedaker, Shepard M.This experiment was carried out in a mature (> 100-year-old) eastern beech forest in the Eastern Black Sea Region (BSR) of Turkey. The effects of experimental practices to control the woody plant Rhododendron flavum Don., including grubbing, manual cutting, and foliar and cut-stump spraying with imazapyr and triclopyr, were assessed on understory and forest floor biomass and nutrients, as well as soil bulk density and nutrient content. The cut plots had 5, 15, and 38 times greater competing vegetation biomass than did the plots treated with triclopyr, grubbing, and imazapyr, respectively. Because of the increased biomass, the amount of understory N, P, Ca, K, S, and Mg content on the cut plots was also substantially higher when compared to the grubbed, imazapyr-treated, and triclopyr-treated plots. Triclopyr and imazapyr applications brought about two- and threefold greater dead organic matter on the forest floor than did cutting and grubbing, respectively. As a result, forest floor macronutrient contents on the imazapyr- and triclopyr-treated plots were significantly greater than on the cut plots. Five years after treatments, soil bulk density at the 10-20 cm depth on the imazapyr-sprayed plots was about 14% higher than that on other treatments. Herbicides, especially imazapyr and grubbing were effective in controlling rhododendron. Macronutrients stored in the rhododendron were released to the forest floor after vegetation was controlled with herbicides.Öğe Long-term site productivity effects of different Rhododendron control methods in eastern beech (Fagus orientalis Lipsky) ecosystems in the Western Black Sea region of Turkey(Wiley-Blackwell Publishing, Inc, 2009) Yıldız, Oktay; Eşen, Derya; Sargıncı, MuratThe study area is located in an eastern beech stand on a fertile and mesic upland site in the western Black Sea region of Turkey. During natural regeneration of the beech stand, rhododendron was differentially controlled. The experiment used a randomized block design with four replicates and two different site preparation practices. The manual treatment was hand grubbing. The whole plant was uprooted and left on the site. The mechanical treatment scarified the surface soil to 5-10 cm depth with a bulldozer equipped with a brush rake. After 17 years following site preparation, the number of trees on the grubbing site (GS) was 60% more than that of mechanical treatment sites (MTS). Total tree biomass per hectare was 39% greater on GS than that of MTS. Beech trees on the grubbing sites had 18, 115, 29, 17 and 78% more N, P, K, Ca and Mg than MTS, respectively. Forest floor N content on GS was 50% more than that of MTS. On the GS, Ca content also was three times more than that of MTS. At 0-20 cm depth, cation exchange capacity on GS was 48% higher than that of MTS. At the same depth, GS had 50, 100, 78, 23, 8, 10 and 49% more C, N, P, Ca, K, Mg and S concentrations than those of MTS, respectively. Removing of organic layer and upper soil with mechanical site preparation depletes ecosystem nutrient pools compared with manual grubbing. This difference is sustained in the long-term. Grubbing is both effective and by leaving organic layer on the sites, grubbing preserves the long-term productivity of the ecosystem.Öğe Seed screening of three pine species for glyphosate sensitivity for forest restoration(Taylor & Francis Ltd, 2018) Türedi, Mustafa; Eşen, Derya; Çetin, BilalAustrian black pine (Pinus nigra J.F. Arnold), Scots pine (Pinus sylvestris L.), and maritime pine (Pinus pinaster Aiton) are commonly used in restoration practices in the Mediterranean base including Turkey. Direct seeding can secure desired level of tree establishment and survival on degraded sites wherever, favorable safe sites are scattered throughout the landscape. Glyphosate is a commonly used herbicide for weed control in forest, nursery and restoration sites worldwide, due to its broad-spectrum efficacy and considerably less toxicity on the environment compared to other chemicals. The present study screened the glyphosate phytotoxicity of three dominant pine species in Turkey during a seed germination trial, after seeds had been presoaked in 15 different dose-glyphosate solutions varying between 0 and 5%, v:v. Glyphosate applications damaged seed germination speed more than cumulative germination rate. As a systemic herbicide, glyphosate appeared highly phytotoxic to Austrian black pine. Scots pine showed an intermediate glyphosate phytotoxicity. Maritime pine was the least sensitive species, tolerating glyphosate at1% doses. In conclusion, glyphosate may be used at low doses on restoration sites seeded with maritime pine while it is not recommended to be used on degraded sites seeded with Austrian black pine and Scots pine.Öğe Tuz Gölü-Konya Havzasında Bulunan Ağaçlandırma Sahalarında Ağaç Türlerinin Başarı Oranları ile Toprak Özelliklerinde Meydana Gelen Değişimin Belirlenmesi(2021) Toprak, Bülent; Yıldız, Fatih Oktay; Çetin, Bilal; Sargıncı, Murat; Eşen, DeryaÇalısmanın amacı; Iç Anadolu kurak sahalarında yapılan agaçlandırma çalısmalarının uzun vadede ekosistem restorasyonuna katkısını belirlemektir. Çalısma için Tuz Gölü-Konya havzasında bulunan farklı yaslardaki (karaçam (Pinus nigra), igde (Elaeagnus angustifolia), badem (Amygdalus communis), yalancı akasya (Robinia pseudoacacia), disbudak (Fraxinus angustifolia) ve mahlep (Prunus mahalep) agaçlandırma sahalarından örneklemeler yapılmıstır. Örnekleme alanlarında agaçların türü, yasama oranları, boy ve çap degerleri, son bes yıllık boy artımları kaydedilmistir. Ayrıca sahalarda önce ölü-örtü örneklemesi yapılmıs daha sonra sahayı temsil edecek toprak profilleri kazılmıs hem profilden hem de tüm örnekleme sahalarından belirli noktalarda ilk 30 cm derinlikten 2 set toprak örnekleri alınmıstır. Toprak örneklerinde hacim agırlıgı, tekstür, kireç içerigi, pH, tuzluluk, KDK, C ve N analizleri yapılmıstır. Veriler blok desenine göre analiz edilmistir. Toprak analizleri için agaçlandırma sahasının dısındaki kontrol degerleri co-variance olarak kullanılmıstır. Analiz sonuçlarına göre agaçlandırmanın ilk 8-10 yılında karaçam fidanlarının yaklasık 2/3 ?ü ölmüstür. Badem ve mahlep fidanlarında ise kayıp oranı yaklasık % 20?dir. Agaçlandırmanın 25-27. yılında ise badem 1/3?ünü, igde 2/3?ünü kaybetmis, diger türlerin ise baslangıçtaki bireylerinin yaklasık % 80?i kurumustur. Karaçam son 10 ile 25 yasa aralıgında yaklasık 11 kat boy artımı yaparak 6.5 metrenin üstünde boya ulasmıstır. Aynı dönemde akasyada boy artımı 2.8, bademde 2.6, disbudakta 2.5 kat olurken en az boy artısı 1.7 katla mahlepte görülmüstür. Tüm türlerin verileri topluca degerlendirildiginde agaçlandırmanın ilk 8-10 yılında açık alana göre sahadaki ölü-örtü miktarı 3 kat, 15-17. yılında 5 kat ve 25-27 yılında ise yaklasık 8 kat artmıstır. Her yas agalıgındaki tüm türlere ait veriler birlikte degerlendirildiginde agaçlandırmanın 15-17. yılından itibaren ilk 30 cm toprak derinligindeki N yogunlugunun açık alana göre yaklasık 1/3 oranında arttıgı görülmektedir. Ilk 30 cm deki pH degerinin ise 25-27 yılları arasında diger sahalara göre 0.15 birim azaldıgı görülmektedir. Veriler tüm sahalarda toprak verimliliginde restorasyonun basladıgı göstermektedir.
