One of the fundamental questions in community ecology is whether communities are random or formed by deterministic mechanisms. Although many efforts have been made to verify non-randomness in community structure, litt...One of the fundamental questions in community ecology is whether communities are random or formed by deterministic mechanisms. Although many efforts have been made to verify non-randomness in community structure, little is known with regard to co-occurrence patterns in above-ground and below-ground communities. In this paper, we used a null model to test non-randomness in the structure of the above-ground and below-ground mite communities in farmland of the Sanjiang Plain, Northeast China. Then, we used four tests for non-randomness to recognize species pairs that would be demonstrated as significantly aggregated or segregated co-occurrences of the above-ground and below-ground mite communities. The pattern of the above-ground mite commu- nity was significantly non-random in October, suggesting species segregation and hence interspecific competition. Additionally, species co-occurrence patterns did not differ from randomness in the above-ground mite community in August or in below-ground mite com- munities in August and October. Only one significant species pair was detected in the above-ground mite community in August, while no significant species pairs were recognized in the above-ground mite community in October or in the below-ground mite communities in August and October. The results indicate that non-randomness and significant species pairs may not be the general rule in the above-ground and below-ground mite communities in farmland of the Sanjiang Plain at the fine scale.展开更多
A crucial impact of climate change is the disruption of the agricultural sector,posing a threat to food supply for the globally increasing population.In this context,prioritizing food security in each country becomes ...A crucial impact of climate change is the disruption of the agricultural sector,posing a threat to food supply for the globally increasing population.In this context,prioritizing food security in each country becomes an important concern.This study aimed to explore biomass and C-Stock content of Sago forests for handling climate change and resilience.The methodology used comprised various steps including determining the type and the hydraulic conductivity of the soil,assessing biomass and C-Stock by cutting Sago at various growth stages,weighing the wet and dry weight of each fraction,calculating the Top-Root Ratio,and determining the starch yield.The results showed that there were four types of soil namely Hydric,District,and Fluvic Gleisol,as well as Oxic Cambisole.C-Stock was 26.99 tonnes per hectare with a Top-Root Ratio of 636%,implying that above-ground biomass(AGB)was six times more than below-ground biomass(BGB)and the presence of mineral soil.Sago dry starch product ranged from 490.3–571.8 kg per tree and the potential relatively varied due to differences in the structure and composition of forests,as well as habitat and environment.Although logging remained persistent on a very small scale,early signs of disturbances were observed in hydrological conditions and fluctuations in water levels or puddles in the soil profile.This implied that conversion of Sago forests to other uses for the expansion of grain crops on a large scale,would lead to the area experiencing drought.展开更多
Land reclamation is a process of ecosystem reconstruction, for which it is very important to keep co-adaptation between plants and the below ground habitat. In order to keep the co-adaptation among plant species, thic...Land reclamation is a process of ecosystem reconstruction, for which it is very important to keep co-adaptation between plants and the below ground habitat. In order to keep the co-adaptation among plant species, thickness of covering soil and medium of covering soil to establish a self-regulating ecosystem, the thickness of covering soil of land reclamation for plants in different living forms by synusia structure of plant below-ground habitat and medium of covering soil by ecological factors of plant below-ground habitat were studied. Synusia structure of plant below-ground habitat was recognized through investigation on structure and root of plant community, and ecological factors were determined through soil profile investigation. The thickness and medium of covering soil of land reclamation for the tree, the shrub and the herb were proposed.展开更多
基金Under the auspices of National Natural Science Foundation of China(No.41101049,40601047,41371072,31101617,41171047)China Postdoctoral Science Foundation(No.2012M511361)+2 种基金Excellent Youth Scholars of Northeast Institute of Geography and Agroecology,Chinese Academy of Sciences(No.DLSYQ2012004)Fund for Distinguished Young Scholar of Harbin Normal University(No.KGB201204)Scientific Innovation Project for Doctoral Candidate of Harbin Normal University(No.HSDBSCX2012-07)
文摘One of the fundamental questions in community ecology is whether communities are random or formed by deterministic mechanisms. Although many efforts have been made to verify non-randomness in community structure, little is known with regard to co-occurrence patterns in above-ground and below-ground communities. In this paper, we used a null model to test non-randomness in the structure of the above-ground and below-ground mite communities in farmland of the Sanjiang Plain, Northeast China. Then, we used four tests for non-randomness to recognize species pairs that would be demonstrated as significantly aggregated or segregated co-occurrences of the above-ground and below-ground mite communities. The pattern of the above-ground mite commu- nity was significantly non-random in October, suggesting species segregation and hence interspecific competition. Additionally, species co-occurrence patterns did not differ from randomness in the above-ground mite community in August or in below-ground mite com- munities in August and October. Only one significant species pair was detected in the above-ground mite community in August, while no significant species pairs were recognized in the above-ground mite community in October or in the below-ground mite communities in August and October. The results indicate that non-randomness and significant species pairs may not be the general rule in the above-ground and below-ground mite communities in farmland of the Sanjiang Plain at the fine scale.
基金supported by the Dean of Agricultural Faculty,Pattimura University.
文摘A crucial impact of climate change is the disruption of the agricultural sector,posing a threat to food supply for the globally increasing population.In this context,prioritizing food security in each country becomes an important concern.This study aimed to explore biomass and C-Stock content of Sago forests for handling climate change and resilience.The methodology used comprised various steps including determining the type and the hydraulic conductivity of the soil,assessing biomass and C-Stock by cutting Sago at various growth stages,weighing the wet and dry weight of each fraction,calculating the Top-Root Ratio,and determining the starch yield.The results showed that there were four types of soil namely Hydric,District,and Fluvic Gleisol,as well as Oxic Cambisole.C-Stock was 26.99 tonnes per hectare with a Top-Root Ratio of 636%,implying that above-ground biomass(AGB)was six times more than below-ground biomass(BGB)and the presence of mineral soil.Sago dry starch product ranged from 490.3–571.8 kg per tree and the potential relatively varied due to differences in the structure and composition of forests,as well as habitat and environment.Although logging remained persistent on a very small scale,early signs of disturbances were observed in hydrological conditions and fluctuations in water levels or puddles in the soil profile.This implied that conversion of Sago forests to other uses for the expansion of grain crops on a large scale,would lead to the area experiencing drought.
文摘Land reclamation is a process of ecosystem reconstruction, for which it is very important to keep co-adaptation between plants and the below ground habitat. In order to keep the co-adaptation among plant species, thickness of covering soil and medium of covering soil to establish a self-regulating ecosystem, the thickness of covering soil of land reclamation for plants in different living forms by synusia structure of plant below-ground habitat and medium of covering soil by ecological factors of plant below-ground habitat were studied. Synusia structure of plant below-ground habitat was recognized through investigation on structure and root of plant community, and ecological factors were determined through soil profile investigation. The thickness and medium of covering soil of land reclamation for the tree, the shrub and the herb were proposed.
