Effects of Contour Furrow on Ecological Indices of Range Health Using Landscape Function Analysis (Case study: Ghick Sheikha Rangeland, Jiroft, Iran)

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1 International Journal of Scientific Research in Environmental Sciences, 2(12), pp , 2014 Available online at ISSN: ; 2014; Author(s) retain the copyright of this article Full Length Research Paper Effects of Contour Furrow on Ecological Indices of Range Health Using Landscape Function Analysis (Case study: Ghick Sheikha Rangeland, Jiroft, Iran) Mahdieh Ebrahimi 1 *, Mohadese Arab 2 1 Assistant Professor, Department of Range and Watershed Management, University of Zabol, Iran 2 M.Sc of Range management, Department of Range and Watershed Management, Faculty of Water and Soil, University of Zabol, Iran *Corresponding Author, maebrahimi2007@uoz.ac.ir Received 16 October 2014; Accepted 27 November 2014 Abstract. Restoration practices have important impact on soil surface and functional characteristic of rangelands. So, for the sustainable utilization of the rangelands, these changes should be recognized and managed. The present study was conducted to recognize the effects of contour furrow on ecological indices of rangeland health in Ghick Sheikha contour furrow (Jiroft) using landscape function analysis. A free contour furrow (as control) was also selected to compare the effects of contour furrow on soil factors and vegetation cover. In this method, 11 soil parameters were assessed to recognize three functional properties, including stability, infiltration and nutrient cycling (using analysis of landscape function software) and, paired t-test was used to compare the performance indicators in the control and contour furrow. However the number of patches was more in the control treatment, the results showed that in the contour furrow area, the length of ecological components (patches) was more than in the control treatment. Three health indicators in the contour furrow were more than in the control treatment and there was a significant difference between two areas (p 0.05). In addition, regression model analyses between two areas suggested that the parameters of litter movement, soil surface resistance to erosion, soil surface roughness, and erosion in contour furrow and soil surface roughness, litter cover and soil surface resistance to erosion in the control area had respectively the biggest share among the rangeland health indicators. Generally, the present study suggested effectiveness of contour furrow compared to the control. Keywords: Contour furrow, ecological indices, landscape function analysis, rangeland health 1. INTRODUCTION In Iran, rangelands are of the highest extent regarding the other natural ecosystems (Mogaddam, 2006) and most of the rangelands have encountered the changes in vegetation trend and conditions as well as soil erosion resulting in the reduction of plant and livestock production due to incorrect management and exploitation (Azarnivand and Zare Chahoki., 2012). Rangelands having native vegetation and natural potential are managed as a natural ecosystem. Considering ecology, the recognition of fundamental ecologic concepts and the evaluation of ecosystem play significant roles in recognizing the ecosystems' structure and function. Changing the ecologic concepts and assumptions is more likely to alter the range evaluation (Abedi and Arzani, 2004). The Dynamic ecosystem is changed because of environmental disturbances so that the sustainable exploitation will be possible when these changes are identified. Some changes are regarded as ecosystems' 449 natural ones; however, if these changes go over the habitat's protective threshold, they are to destroy the rangeland (Sabeti, 1975). Range management is based on the ecologic principles and management evaluations of rangelands are mainly based on structural ones which are conducted quantitatively concerning production, canopy cover p, plant density and composition while not paying attention to health evaluation models which apply modern methods (Ahmadi et al., 2009). Every range ecosystem is consisted of various ecologic patches with different functions and functional and structural properties of fertile parts which can be used to interpret the management roles in the rangelands are to be altered due to corrective actions (Heshmati et al., 2010). In order to investigate the effects of corrective actions on rangeland restoration, their functions should be assessed and ecologic processes have to be considered for the recognition of functions. Studies have shown that the determination of primary

2 Ebrahimi and Arab Effects of Contour Furrow on Ecological Indices of Range Health Using Landscape Function Analysis (Case study: Ghick Sheikha Rangeland, Jiroft, Iran) ecologic processes is difficult and costly due to the complexity of processes and internal relations. Therefore, three properties of ecologic processes including range soil stability, nutrient cycle and hydrological range conditions are of significant importance to evaluate the range management and planning. In this respect, landscape function analysis is presented (Tongway and Hindley, 2004) in order to assess the effects of corrective and management actions on rangelands based on functional and structural properties using eleven soil surface indices and three functional features involving stability (soil ability to resist against the erosive elements and its reversibility after the occurrence of disturbances), permeability (water retention rate in soil for plants) and nutrient cycle ( reversibility rate of organic matters into soil). Evaluating the habitats' potentials using soil surface properties, it has been reported that these indices can be regarded as suitable elements for determining the habitat potentials and plant composition (Rezaei and Arzani, 2007). Also, for evaluating the soil surface properties to specify the range conditions, the efficiency of landscape function analysis was studied and compared to six-factors and four-factors methods and it has been found that landscape function analysis is of more accuracy and efficiency (Ghelichnia et al., 2008). Evaluating the effects of corrective actions on the rangelands of Amari Sarchah in Birjand (Iran) using landscape function analysis, it was reported that the corrective actions including disclosure and construction of a crescent pond led to the improvement of functional properties (Yari et al., 2012). This paper aims to evaluate the effects of contour furrow on three functional properties such as stability, permeability and nutrient cycle in Gick Sheikha rangelands in Anbarabad region, Jiroft city, Iran using landscape function analysis method; in other words, Has contour furrow improved the mentioned functional indices in the studied rangeland? 2. MATERIALS AND METHODS 2.1. The study area The rangeland under examination with the area of 3047 ha is located in 60 km of Jiroft city, Kerman province, Iran, between northern latitude and 58 3 eastern longitude (Fig. 1). The average height of the area is 900 meter of sea surface level with an annual average precipitation of mm, and maximum and minimum average temperature of and 15 C respectively Methodology A field operation was done during the flowering stage of dominant plant species. After conducting primary investigations, sampling was performed along linear transects by a randomized systematic method according to previous range plans and field visits. Thus, three 100 m transects were established by the intervals of 100 m. In each transect, patches having the existing vegetation were selected and afterwards, 5 replicates of patches and inter patches with bare soil were randomly chosen. Then, the length and width of ecologic patch and the length of inter patches in transects have been recorded. In order to compare the impacts of contour furrow on soil and vegetation factors by the means of landscape functional analysis, a control treatment (without contour furrow operation) has been considered along the desired region. In each region, soil surface indices were investigated in order to study the soil stability, permeability and nutrient cycle. These indices include soil conservation, litter cover, cryptogam cover, crust crunching, erosion type and intensity, sedimentations, soil surface nature, surface resist to disturb, vegetation indices of perennial species, soil surface roughness, soil texture, permeability and nutrient cycle. Then, they were calculated by the sum of indices' scores. Statistical data analysis was performed using Excel software of landscape function analysis. Contour furrow and control treatment were compared by T-test. In addition, multiple linear regression has been applied using SPPSS.18 in order to specify the best indices which affect the range health. 3. RESULTS 3.1. Ecologic patches characteristics in contour furrow and control treatments Quantitative characteristics and ecologic indices of contour furrow and control treatments indicate that in the studied region, the mean length of ecologic patches is 0.93 m whereas it is given as 0.52 m for the control treatment. Number of patches was 22 and 6 for the control and contour furrow treatments, respectively. Patch area index (mean area divided by total number of patches) has been computed as 0.05 and for contour furrow and control treatments, respectively. Specificity index demonstrating the landscape potential and capability was given as 1 for both treatments (Table 1). 450

3 International Journal of Scientific Research in Environmental Sciences, 2(12), pp , 2014 Fig. 1: The Study Area 3.2. Comparison of functional indices in ecologic patch of contour furrow and control treatments In furrow contour treatment (Table 2), patches functional indices were of higher values with respect to the number and area of patches in the ecosystem as compared to the control treatment; patches stability values were and 32.05%, nutrient cycle percent was and and permeability percent was estimated and for contour furrow and control treatments, respectively. Therefore, studying the indices in contour furrow treatment showed that three indices of stability, permeability and nutrient cycle are higher than those for control treatment on the basis of number of area of patches. Results of t test indicate that there is a significant difference between the functional indices of two regions (p<0.05) so that three desired indices in furrow contour treatment are more than control one. In general, results of two desired regions show that range health indices in furrow contour treatment are averagely higher than control one. Table 1: Characteristics of ecologic patches in contour furrow area and control treatment *Values within a column followed by different letters indicate significant differences. Mean values are reported with SE (Standard Error) 3.3. Most important effective range health indices in contour furrow and control treatments Considering table 3, there is a positive relationship between erosion intensity and surface resistance concerning the corrective actions of furrow contour treatment and stability index with regard to regression model; stability percent is added by 1.2 due to low and moderate erosion intensities when ecologic index of erosion intensity is increased by 1. Enhancing the surface resistance, soil stability percent is increased by Permeability index which is regarded as one of functional properties is in relation to litter cover and soil surface resistance against erosion. Other ecologic indices such as basal area, soil surface roughness, surface resist to humidity and soil texture were removed from the regression model. Nutrient cycle index involves basal area, litter cover, soil surface roughness and cryptogams cover. Based on the existing regression model, two elements of litter cover and soil surface roughness affected this index and was directly related to nutrient cycle. As

4 Ebrahimi and Arab Effects of Contour Furrow on Ecological Indices of Range Health Using Landscape Function Analysis (Case study: Ghick Sheikha Rangeland, Jiroft, Iran) litter cover and soil surface roughness increase by 1, nutrient cycle percent is increased by 5.96 and 1.66, respectively. Based on table 3, corrective actions of contour furrow and control treatments and regression models of three desired indices, among 11 studied indices, stability has a relationship with litter cover and soil surface resistance in such a manner that it is directly related to litter cover. As litter cover increases by 1, stability percent is increased by Soil surface resistance has a negative relationship with stability. As soil surface resistance increases by 1, stability is decreased by 1.80%. Considering permeability index and six factors including basal area, litter cover, surface roughness, stability test against humidity, soil texture and soil surface resistance against erosion, only two factors of litter cover and soil surface resistance affected this index while having a positive direct relationship. As litter cover increases by 1, permeability is increased by 1.80%. As soil surface resistance percent against erosion increases by 1, permeability is increased by 2.35%. Considering nutrient cycle index and four factors of basal area, litter cover, cryptogams and soil surface roughness, only two factors of litter cover and soil surface roughness were examined and basal area and cryptogams cover with negative relationships were ignored. As litter cover increases by 1, permeability percent is decreased by As soil surface roughness increases by 1, permeability percent is decreased by Table 2: Means of the LFA indices in patches in contour furrow area and control treatment Table 3: Most important effective range health indices in contour furrow area and control treatments *S= Stability, E= Erosion, Sr= Surface Resist to disturb, I= Infiltration, N= Nutrient cycling status, Lc=Litter cover; Ss= Soil Surface Roughness 3.4. Correlation coefficients among functional indices Based on table 4, stability index has negative correlations with litter cover, erosion, sedimentation and cryptogams while it is positively correlated with crust crunching and surface resistance. Maximum correlation coefficient of this index was given as 99% for sedimentation and crust crunching. Permeability has positive correlations with cryptogams cover, litter decomposition and surface resistance while it is of a negative correlation with surface roughness. Maximum correlation of permeability was calculated as 99% with cryptogams cover. Similar results have been achieved for nutrient cycle in such a manner that this index has positive correlations with basal area, litter decomposition and surface roughness. Maximum 452

5 International Journal of Scientific Research in Environmental Sciences, 2(12), pp , 2014 correlation coefficient as 94% was given for litter decomposition. Based on table 4, stability index is of positive correlations with litter cover, erosion and sedimentation while having a negative correlation with surface resistance. Maximum correlation coefficient of this index was obtained as 99% for surface resistance. Permeability index is correlated with cryptogams cover, surface roughness and surface resistance with maximum correlation coefficient as 97%. Minimum correlation coefficient was given for soil texture. Maximum correlation coefficient was calculated as 82% for litter decomposition. Table 4: Correlation coefficients among three function indices and effective factors in contour furrow area and control treatment 4. DISCUSSION Destructive range elements are the excessive presence of livestock and over grazing so that management measures lead to the changes in soil surface properties and range functional features. In the studied regions, contour furrow treatment along with the grazing management resulted in the changes of soil surface properties and range functional features in such a manner that these indices were reduced in control treatment as compared to contour furrow treatment having the grazing management. Rangelands involve a variety of natural resources extensively. As a result, it is necessary to evaluate rangelands in order to achieve the sustainable and long-term exploitations and make decisions on the range changes. Range function studies make the judgments possible on the impacts of corrective and management actions on primary ecosystem processes such as water cycle, energy movement and materials' cycle using several simple indices (Toranjzar et al., 2009). Investigating the effects of grazing on range health, it has been observed that in the regions with less grazing, soil properties are of better mean values while in the regions with inappropriate management, over grazing and range plowing, range conditions are not healthy (Tongway and Hindley, 2004). Results show that range management affects the ecologic range properties directly which are dependent on vegetation and soil characteristics and alters the ecological indices of Gick Sheikha rangeland. Contour furrow landscape along with the grazing management is of higher average than the control treatment regarding the studied indices showing that corrective actions led to the relative improvement of rangeland. However, control treatment which was not managed correctly has lower averages as compared to furrow contour treatment 453

6 Ebrahimi and Arab Effects of Contour Furrow on Ecological Indices of Range Health Using Landscape Function Analysis (Case study: Ghick Sheikha Rangeland, Jiroft, Iran) with corrective actions; namely, contour furrow one is of better health. In fact, plant species affect the range conditions through creating suitable environmental conditions and contour furrow treatment has the highest functional properties and appropriate range health concerning stability, permeability and nutrient cycle due to the existence of more ecologic patches as compared to control treatment. In contour furrow landscape, patches have the highest stability percent because of extensive canopy cover. As a result of soil compaction because of trampling and the decreases of roughness and vegetation, permeability is more likely to be reduced. On the other hand, the removal of cryptogams cover and reduction of vegetation and litter decrease the nutrient cycle value. Also, the increase of soil roughness, permeability is highly to be increased (Bridge et al., 1983). Eroded matter percent and various forms of erosion in contour furrow treatment are significantly less than control treatment indicating better conditions of stability, permeability and nutrient cycle. Studying the effects of different corrective actions on soil surface indices, it has been reported that eroded matter percent is increased by the intensification of grazing so that soil roughness is reduced by the increase in grazing; consequently, vegetation and litter cover are decreased (Arzani et al., 2007; Ghoddousi et al., 2006). In contour furrow treatment, such parameters as litter cover, soil surface resistance against erosion and erosion intensity have the highest shares in the regression model and litter cover is of direct relationships with nutrient cycle and permeability. Surface roughness and nutrient cycle are directly related because the decrease of roughness leads to low reservation of nutrients at the soil surface. In contour furrow region, since the region has soil surface roughness, nutrient cycle is enhanced due to the effects of litter decomposition (Heshmati et al., 2008). Roughness at the soil surface decelerates the intensity of outputs and accelerates the permeability while creating a safe environment for the aggregation of seeds and litter (Heshmati et al., 2008). It can enhance the vegetation in contour furrow region as compared to the control one. On the other hand, soil surface properties affect the range features directly so that such factors as plant species, vegetative form and vegetation are influenced. Plants including small bushes, grasses and trees create an environment with microclimate which is more moderate than the external environment in summer and winter and plays crucial roles in stabilizing soil and avoiding the erosion (Sabeti, 1975). In control region, surface roughness, litter cover and soil surface resistance to disturb have the highest 454 shares in the regression model. Soil surface resistance against erosion is negative which decreases the stability value. Given soil surface resistance that is put in the class of relatively hard, this region's stability is decreased by 1.8%. Permeability is influenced by two factors of litter and soil surface resistance while having direct positive relationships due to soil texture since soil texture of his region is not hard so that it has high permeability. 5. CONCLUSION Generally, landscape function analysis is introduced as a suitable and simple method which assesses the impacts of management measures on the basis of functional and structural characteristics. In this paper, the effects of contour furrow operation were compared with control one; however, to investigate the partial impacts of one management activity or a grazing program, a monitoring plan can be designed in order to study the qualitative and quantitative variations of species functions and interpret the destruction trend and range correction by the help of these species and patches. ACKNOWLEDGEMENTS Authors express their thanks to department of range and watershed management, University of Zabol for providing necessary facilities to undertake this study. REFERENCES Abedi M, Arzani H (2004). Determination rangeland health attribute by ecological indicators, a new viewpoint in Range Assessment. Iranian Journal of Range and Forest, 56: Ahmadi Z, Heshmati Gh A, Abedi M (2009). 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7 International Journal of Scientific Research in Environmental Sciences, 2(12), pp , 2014 Briske DD, Fuhlendruf SD, Smeins EF (2003). Vegetation dynamics on rangelands: a critique of the current paradigms. Journal of Appl. Ecology, 40: Ghelichnia H, Heshmati GA, Chaichi MR (2008). The compare of assessment rangeland condition with soil properties method and 4 factors method in shrublands of Golestan National Park. Iranian Journal of Watershed Management Research (Pajouhesh & Sazandegi), 78: Ghoddousi J, Tavakoli M, Khalkhali SA, Soltani MJ (2006). Assessing effect of rangeland exclusion on control and reduction of soil erosion rate and sediment yield. Iranian Journal of Watershed Management Research (Pajouhesh & Sazandegi), 73: Heshmati GA, Naseri K, Ghanbarian G (2008). Landscape function analysis: procedures for monitoring and assessing landscape, Mshhad Jahad Daneshgahi press, Mshhad, Iran. Heshmati GA, Azimi MS, Ashouri P (2010). Assessment of Structural Characteristics of Fertilized Patch in Rangeland Ecosystems (Case Study: Ghareh Ghir and Maraveh Tapeh Rangelands of Golestan Province). Iranian Journal of Range and Watershed Management, 63(3): Mogaddam MR (2006). Range and Rangemanagement. 3rd edition, University of Tehran press, Tehran, Iran. Noy-Meir I (1973). Desert ecosystems: environment and producers. Annu. Rev. Ecol. Evol. Syst., 4: Rezaei SA, Arzani H (2007). The use of soil surface attributes in rangelands capability assessment. Iranian Journal of Range and Desert Reseach, 14 (2): Sabeti HA (1975). Relation between plant and environment (synecology). Dehkhoda press, Tehran, Iran. SRM Task Group (Society for Range Management Task Groups on Unity in Concept and Terminology Committee, Society for Range Management) (1995). New concepts for assessment of rangeland condition. Journal of range manage., 48: Tongway DJ, Hindley NL (2004). Landscape Function Analysis: a system for monitoring rangeland function. Afr J Range Forage Sci., 21: Toranjzar H, Abedi M, Ahmadi A, Ahmadi Z (2009). Assessment of rangeland condition (health) in Meyghan desert of Arak. Journal of Rangeland., 3(2): Yari R, Tavili A, Zare S (2012). Investigation on soil surface indicators and rangeland functional attributes by Landscape Function Analysis (LFA) (Case study: Sarchah Amari Birjand). Iranian Journal of Range and Desert Reseach, 18 (4):

8 Ebrahimi and Arab Effects of Contour Furrow on Ecological Indices of Range Health Using Landscape Function Analysis (Case study: Ghick Sheikha Rangeland, Jiroft, Iran) Dr. Mahdieh Ebrahimi, is an assistant professor in Department of Range and Watershed management, University of Zabol, Iran. She obtained M.Sc. and Ph. D degrees in Range management from University of Tehran, Iran in 2006 and 2011 respectively. She has published books, national and international research papers. Her field of interest includes Range management and phytoremediation. Mohadese Arab obtained a Bachelor of Science Degree in Range and watershed management in 2010 and Master of Science Degree in Range management in 2012 from University of Zabol, Iran. She works with University of Bahonar, Kerman, Iran as a Research Officer at the Department of Natural Resources. Her current research is focuses on range and watershed management. To date, she has published several scientific articles related to reclamation of rangelands. 456