The impact of five environmental factors on species distribution and weed community structure in the coastal farmland and adjacent territories in the northwest delta region, Egypt

Abstract

The importance of the soil type and its properties cannot be denied as one of the major environmental factors affecting the weed community structure in an area, but what is the effect of the other environmental factors as the prevailing climate, crop type, urbanization and crop sustainability? What is the order of importance for their impact? The present study aims to measure these concepts. A sample area (3500 km 2 ) was selected in the Northwest Delta, Egypt. 473 species recorded and four VSG or vegetative sociation groups (weed communities) identified using Agglomerative Hierarchical Clustering (AHC). The diversity of the 4 VSG was calculated. PCA used to get a view for the influence of these five variables (environmental factors) on species distribution and variability of weed community structure, summarize the relationships among variables and investigate the proximity among samples and how they relate to variables. The measurement of the degree of seasonal bias of species added more clarification for the impact of crop type. ANOVA followed by Tukey's test showed the significance of 9 soil variables and determined which of the pairs were statistically significant. The results of the study revealed that the prevailing climate was the most impacting factor on species distribution and weed community structure followed by urbanization, crop type, soil type and crop sustainability, respectively.

Cereal weeds variation in middle Egypt: Role of crop family in weed composition

“…The Dendrograms obtained the Ward classification of weed composition showed that differences in weed species compositions were mainly affected by seasonal priority. The current results confirmed previous studies, which concluded that the crop season is the most significant factor in the floristic composition of Egyptian weed species ( El-Hadidi and Kosinová, 1971 , Mahgoub, 2019b ), and in central Europe ( Lososová, et al, 2004 ).…”

Participatory assessment of lentil (Lens culinaris Medik.) production practices in marginal dry lands of Wag-lasta, Ethiopia

“…where S 2 is sample variance, Σ is sum, x i is the term in data set (indicative scores of sampling sites), x is sample mean, and n is sample size (Alaa and Mahgoub, 2019). The results of ANOVA (R 2 , F, P) and the sample variance (S 2 ) have been taken to express for the impact of the agronomic records and their order of importance, on the different treatments of the trial area.…”

Comparative view for the impact of five eco factors on species distribution and weed community structure in Isthmus of Suez and adjoining farmland east Nile delta, Egypt

“…The study of the extent of variability and order of importance for the impact of environmental factors on species distribution and weed community structure from one region to the other is an interesting research subject. In a previous research on coastal farmland and adjacent territories in Northwest Delta region, the author determined the extent of variability and order of importance for the impact of five environmental factors on species distribution and weed community structure (Mahgoub, 2019). It was concluded that the heavy rainy winters caused a remarkable increase of the total species richness γ-diversity, Whittaker.…”

“…But you cannot point to one single eco factor responsible for biodiversity of communities or diversity of weed communities or vegetative sociation groups (VSG) or even for a community. You can say, however, that weed communities or vegetative sociation groups (VSG) are determined by the combined effects of several eco factors and it could be expected that an ecological factor may be the dominant in determining the vegetation structure in a certain region and co-factor in another one depending on the available natural resources (Mahgoub, 2019). The structure of weed communities is affected by many factors as farm management practices (Derksen et al., 1994; Andersson and Milberg, 1998; Thomas and Frick, 1993), crop type (Andersson and Milberg, 1998; Andreasen and Skovgaard, 2009), seasonality (El-Demerdash et al., 1997; Mahgoub, 2017) and soil characteristics (Fried et al., 2008; Pinke et al., 2010).…”