a. soffianian

Zayandehroud is the water source for life in Central Iran, but it has become has turned into one of the most vulnerable ecosystem due to human disturbances. In this study, water quality and ecosystem health of Zayandehroud was evaluated in a segment of the river with permanent flow, from the Zayandehrud Regulating Dam to Pol-Kalleh. Water and benthic macroinvertebrate samples were collected from 11 stations during the summer of 2022. The Iranian Water Quality Index for Surface Water (IRWQISC), along with richness and diversity indices, as well as biological indices (BMWP and ASPT), were calculated. The findings revealed that the IRWQISC index categorizes water quality as moderate in most stations, with relatively good quality observed in only three stations. In contrast, the BMWP index denoted poor conditions, the ASPT index reflected severe to moderate pollution levels, and the Shannon diversity index also indicates severe to moderate pollution. The IRWQISC index was unable to accurately capture the effects of water flow interruption downstream of the Cham-Aseman diversion dam and its impact on the deterioration of water quality and overall river ecosystem health. However, the substantial decline in the richness index and biological indices at the Pol-Kalleh station highlights a significant ecological imbalance in the river ecosystem.

In this study, to evaluate the rain- fed land capability in the west of Gavkhooni basin and Plasjn sub- basin, a multi- criteria evaluation method was used. First, by reviewing the literature and expert knowledge, proper data were determined. Criteria and constraint were standardized by Fuzzy and Boolean methods repeatedly and the criteria weights were determined using the analytic hierarchy process. Calculated weights showed that soil and climate criteria with 0.27 and 0.26 had the highest weights among other criteria. Criteria and constraints were combined by considering criteria weights and using the weighted linear combination method; then the rain- fed land capability model was prepared. By re- classing the prepared model, the rain- fed land capability map was produced in 6 capability classes. The results showed that 178430 hectares of the study area was related to very high and high rain- fed capability classes. To determine the rain-fed agriculture sustainability, rain- fed agriculture locations were determined in each land rain- fed capability map. The results showed that 19686 hectares of rain- fed areas were located in high and very high capability and 5999 hectares were the in lower classes.

Landscape ecology as a modern interdisciplinary science offers new concepts, theories, and methods for land evaluation and management. A main part of landscape ecology is describing patterns in the landscape and interpreting the ecological effects of these patterns on flora, fauna, flow of energy and materials. Remote sensing and GIS techniques have a high ability for landscape researchers to specify maps and analyze landscape patterns. We can use the trends in indices to our management decisions. In this study, landscape patterns were quantified by the number and size of land cover patches, the degree of naturalness, and the diversity indices were calculated by GIS approaches and compared for 35 years, in order to reinforce the management efforts of Mouteh wildlife refuge in Iran. The results showed increasing destructions with regards to unplanned human activities, while some natural landscape improvements occurred in the core protected area.